Regional metabolic changes in the hippocampus and posterior cingulate area detected with 3-Tesla magnetic resonance spectroscopy in patients with mild cognitive impairment and Alzheimer disease.

PubMed

Wang, Zhiqun; Zhao, Cheng; Yu, Lei; Zhou, Weidong; Li, Kuncheng

2009-04-01

Magnetic resonance spectroscopy (MRS) plays an important role in early diagnosis of Alzheimer disease (AD). There are many reports on MRS studies among individuals with AD and mild cognitive impairment (MCI). However, very few studies have compared spectroscopic data of different limbic regions among AD and MCI subjects. To compare metabolite changes of different regions in the brain of AD and MCI patients by using 3.0 T short-echo-time MRS. Metabolite ratios in the hippocampus and posterior cingulate area were compared in a group of patients with AD (n=16), MCI (n=16), and normal subjects as a control group (n=16). Clinical neuropsychological tests were measured in all subjects. In the hippocampus, there were significant differences in N-acetylaspartate (NAA)/creatine (Cr), myo-inositol (mI)/Cr, and mI/NAA ratios among the three groups. However, there were no significant differences in choline (Cho)/Cr ratio among the three groups. In the posterior cingulate area, there were no significant differences in the NAA/Cr, Cho/Cr, and mI/Cr ratios among the three groups. However, there were significant differences in mI/NAA ratio between patients with AD and the control group, and between the AD and MCI groups. In addition, there was significant correlation between mI/NAA ratio and Mini Mental Status Exam (MMSE) score in subjects with AD and MCI. The study reveals that the elevation of mI/NAA ratio in the hippocampus is more significant than that in the posterior cingulate area, which corresponds to the pathologic procession of AD. The ratios of mI/NAA in the hippocampus and in the posterior cingulate area together provide valuable discrimination among the three groups (AD, MCI, and controls). There is a significant correlation between mI/NAA ratio and cognitive decline.

The behaviour of fatigue-induced microdamage in compact bone samples from control and ovariectomised sheep.

PubMed

Kennedy, Oran D; Brennan, Orlaith; Mauer, Peter; O'Brien, Fergal J; Rackard, Susan M; Taylor, David; Lee, T Clive

2008-01-01

This study investigates the effect of microdamage on bone quality in osteoporosis using an ovariectomised (OVX) sheep model of osteoporosis. Thirty-four sheep were divided into an OVX group (n=16) and a control group (n=18). Fluorochromes were administered intravenously at 3 monthly intervals after surgery to label bone turnover. After sacrifice, beams were removed from the metatarsal and tested in three-point bending. Following failure, microcracks were identified and quantified in terms of region, location and interaction with osteons. Number of cycles to failure (Nf) was lower in the OVX group relative to controls by approximately 7%. Crack density (CrDn) was higher in the OVX group compared to controls. CrDn was 2.5 and 3.5 times greater in the compressive region compared to tensile in control and OVX bone respectively. Combined results from both groups showed that 91% of cracks remained in interstitial bone, approximately 8% of cracks penetrated unlabelled osteons and less than 1% penetrated into labelled osteons. All cases of labelled osteon penetration occurred in controls. Crack surface density (CrSDn), was 25% higher in the control group compared to OVX. It is known that crack behaviour on meeting microstructural features such as osteons will depend on crack length. We have shown that osteon age also affects crack propagation. Long cracks penetrated unlabelled osteons but not labelled ones. Some cracks in the control group did penetrate labelled osteons. This may be due the fact that control bone is more highly mineralized. CrSDn was increased by 25% in the control group compared to OVX. Further study of these fracture mechanisms will help determine the effect of microdamage on bone quality and how this contributes to bone fragility.

Low Diversity in the Mitogenome of Sperm Whales Revealed by Next-Generation Sequencing

PubMed Central

Alexander, Alana; Steel, Debbie; Slikas, Beth; Hoekzema, Kendra; Carraher, Colm; Parks, Matthew; Cronn, Richard; Baker, C. Scott

2013-01-01

Large population sizes and global distributions generally associate with high mitochondrial DNA control region (CR) diversity. The sperm whale (Physeter macrocephalus) is an exception, showing low CR diversity relative to other cetaceans; however, diversity levels throughout the remainder of the sperm whale mitogenome are unknown. We sequenced 20 mitogenomes from 17 sperm whales representative of worldwide diversity using Next Generation Sequencing (NGS) technologies (Illumina GAIIx, Roche 454 GS Junior). Resequencing of three individuals with both NGS platforms and partial Sanger sequencing showed low discrepancy rates (454-Illumina: 0.0071%; Sanger-Illumina: 0.0034%; and Sanger-454: 0.0023%) confirming suitability of both NGS platforms for investigating low mitogenomic diversity. Using the 17 sperm whale mitogenomes in a phylogenetic reconstruction with 41 other species, including 11 new dolphin mitogenomes, we tested two hypotheses for the low CR diversity. First, the hypothesis that CR-specific constraints have reduced diversity solely in the CR was rejected as diversity was low throughout the mitogenome, not just in the CR (overall diversity π = 0.096%; protein-coding 3rd codon = 0.22%; CR = 0.35%), and CR phylogenetic signal was congruent with protein-coding regions. Second, the hypothesis that slow substitution rates reduced diversity throughout the sperm whale mitogenome was rejected as sperm whales had significantly higher rates of CR evolution and no evidence of slow coding region evolution relative to other cetaceans. The estimated time to most recent common ancestor for sperm whale mitogenomes was 72,800 to 137,400 years ago (95% highest probability density interval), consistent with previous hypotheses of a bottleneck or selective sweep as likely causes of low mitogenome diversity. PMID:23254394

Low diversity in the mitogenome of sperm whales revealed by next-generation sequencing.

PubMed

Alexander, Alana; Steel, Debbie; Slikas, Beth; Hoekzema, Kendra; Carraher, Colm; Parks, Matthew; Cronn, Richard; Baker, C Scott

2013-01-01

Large population sizes and global distributions generally associate with high mitochondrial DNA control region (CR) diversity. The sperm whale (Physeter macrocephalus) is an exception, showing low CR diversity relative to other cetaceans; however, diversity levels throughout the remainder of the sperm whale mitogenome are unknown. We sequenced 20 mitogenomes from 17 sperm whales representative of worldwide diversity using Next Generation Sequencing (NGS) technologies (Illumina GAIIx, Roche 454 GS Junior). Resequencing of three individuals with both NGS platforms and partial Sanger sequencing showed low discrepancy rates (454-Illumina: 0.0071%; Sanger-Illumina: 0.0034%; and Sanger-454: 0.0023%) confirming suitability of both NGS platforms for investigating low mitogenomic diversity. Using the 17 sperm whale mitogenomes in a phylogenetic reconstruction with 41 other species, including 11 new dolphin mitogenomes, we tested two hypotheses for the low CR diversity. First, the hypothesis that CR-specific constraints have reduced diversity solely in the CR was rejected as diversity was low throughout the mitogenome, not just in the CR (overall diversity π = 0.096%; protein-coding 3rd codon = 0.22%; CR = 0.35%), and CR phylogenetic signal was congruent with protein-coding regions. Second, the hypothesis that slow substitution rates reduced diversity throughout the sperm whale mitogenome was rejected as sperm whales had significantly higher rates of CR evolution and no evidence of slow coding region evolution relative to other cetaceans. The estimated time to most recent common ancestor for sperm whale mitogenomes was 72,800 to 137,400 years ago (95% highest probability density interval), consistent with previous hypotheses of a bottleneck or selective sweep as likely causes of low mitogenome diversity.

Quantifying subtle but persistent peri-spine inflammation in vivo to submicron cobalt-chromium alloy particles.

PubMed

Hallab, Nadim James; Chan, Frank W; Harper, Megan L

2012-12-01

We evaluated the consequences of cobalt-chromium alloy (CoCr) wear debris challenge in the peri-spine region to determine the inflammation and toxicity associated with submicron particulates of CoCr-alloy and nickel on the peri-spine. The lumbar epidural spaces of (n = 50) New Zealand white rabbits were challenged with: 2.5 mg CoCr, 5.0 mg CoCr, 10.0 mg CoCr, a positive control (20.0 mg of nickel) and a negative control (ISOVUE-M-300). The CoCr-alloy and Ni particles had a mean diameter of 0.2 and 0.6 μm, respectively. Five rabbits per dose group were studied at 12 and 24 weeks. Local and distant tissues were analyzed histologically and quantitatively analyzed immunohistochemically (TNF-α and IL-6). Histologically, wear particles were observed in all animals. There was no evidence of toxicity or local irritation noted during macroscopic observations in any CoCr-dosed animals. However, Ni-treated control animals experienced bilateral hind leg paralysis and were euthanized at Day 2. Histopathology of the Ni particle-treated group revealed severe neuropathy. Quantitative immunohistochemistry demonstrated a CoCr-alloy dose-dependent increase in cytokines (IL-6, TNF-α, p < 0.05) at 12 and 24 weeks. Subtle peri-spine inflammation associated with CoCr-alloy implant particles was dose dependent and persistent. Neuropathy can be induced by highly reactive Ni particles. This suggests peri-spine challenge with CoCr-alloy implant debris (e.g., TDA) is consistent with past reports using titanium alloy particles, i.e., mild persistent inflammation.

Activity of the external urethral sphincter evoked by genital stimulation in male rats.

PubMed

Juárez, Raúl; Zempoalteca, René; Pacheco, Pablo; Lucio, Rosa Angélica; Medel, Alfonso; Cruz, Yolanda

2016-11-01

To determine whether the external urethral sphincter (EUS) fasciculi of male rats respond to the mechanical stimulation of genital structures and to characterize the pattern of the electromyographic (EMG) activity of the three regions of the EUS: the cranial (CrEUS), the medial (MeEUS) and the caudal (CaEUS). Electromyographic signals were recorded from the CrEUS, MeEUS and CaEUS regions of the male rat's EUS, before, during and after the mechanical stimulation of the urogenital structures. The CrEUS, MeEUS and CaEUS regions responded when brushing and squeezing the foreskin and glans as well as to penile and prostatic urethral distension. The CaEUS EMG amplitude (P < 0.01) and frequency (P < 0.05) were lower in comparison to the CrEUS and MeEUS responses to the mechanical stimulation. In addition, the CaEUS was characterized by a short or no afterdischarge. In contrast, the CrEUS and MeEUS responded by presenting a long discharge after the penile or prostatic urethral distension. The activity of the EUS is modulated by both, cutaneous and visceral genitourinary stimuli, with motor units being activated by mechanoreceptors located in the foreskin, glans, bladder, and urethra. The CrEUS, MeEUS and CaEUS have differential EMG patterns, indicating that the EUS consists of three anatomically and functionally different regions. Precise coordination in the muscular activity of these regions may be crucial for the control of male expulsive urethral functions, i.e., during voiding and ejaculation. Neurourol. Urodynam. 35:914-919, 2016. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

Cerebral diffusion tensor imaging and in vivo proton magnetic resonance spectroscopy in patients with fulminant hepatic failure.

PubMed

Saksena, Sona; Rai, Vijan; Saraswat, Vivek Anand; Rathore, Ramkishore Singh; Purwar, Ankur; Kumar, Manoj; Thomas, M Albert; Gupta, Rakesh Kumar

2008-07-01

Cerebral edema is a major complication in patients with fulminant hepatic failure (FHF). The aim of this study was to evaluate the metabolite alterations and cerebral edema in patients with FHF using in vivo proton magnetic resonance spectroscopy (MRS) and diffusion tensor imaging, and to look for its reversibility in survivors. Ten FHF patients along with 10 controls were studied. Five of the 10 patients who recovered had a repeat imaging after three weeks. N-acetylaspartate, choline (Cho), glutamine (Gln), glutamine/glutamate (Glx), and myoinositol ratios were calculated with respect to creatine (Cr). Mean diffusivity (MD) and fractional anisotropy (FA) were calculated in different brain regions. Patients exhibited significantly increased Gln/Cr and Glx/Cr, and reduced Cho/Cr ratios, compared to controls. In the follow-up study, all metabolite ratios were normalized except Glx/Cr. Significantly decreased Cho/Cr were observed in deceased patients compared to controls. In patients, significantly decreased MD and FA values were observed in most topographical locations of the brain compared to controls. MD and FA values showed insignificant increase in the follow-up study compared to their first study. We conclude that the Cho/Cr ratio appears to be an in vivo marker of prognosis in FHF. Decreased MD values suggest predominant cytotoxic edema may be present. Persistence of imaging and MRS abnormalities at three weeks' clinical recovery suggests that metabolic recovery may take longer than clinical recovery in FHF patients.

Calorie restriction attenuates astrogliosis but not amyloid plaque load in aged rhesus macaques: a preliminary quantitative imaging study

PubMed Central

Sridharan, Aadhavi; Pehar, Mariana; Salamat, M Shahriar; Pugh, Thomas D; Bendlin, Barbara B; Willette, Auriel A; Anderson, Rozalyn M; Kemnitz, Joseph W; Colman, Ricki J; Weindruch, Richard H; Puglielli, Luigi; Johnson, Sterling C

2013-01-01

While moderate calorie restriction (CR) in the absence of malnutrition has been consistently shown to have a systemic, beneficial effect against aging in several animals models, its effect on the brain microstructure in a non-human primate model remains to be studied using post-mortem histopathologic techniques. In the present study, we investigated differences in expression levels of glial fibrillary acid protein (GFAP) and β-amyloid plaque load in the hippocampus and the adjacent cortical areas of 7 Control (ad libitum)-fed and 6 CR male rhesus macaques using immunostaining methods. CR monkeys expressed significantly lower levels (∼30% on average) of GFAP than Controls in the CA region of the hippocampus and entorhinal cortex, suggesting a protective effect of CR in limiting astrogliosis. These results recapitulate the neuroprotective effects of CR seen in shorter-lived animal models. There was a significant positive association between age and average amyloid plaque pathology in these animals, but there was no significant difference in amyloid plaque distribution between the two groups. Two of the seven Control animals (28.6%) and one of the six CR animal (16.7%) did not express any amyloid plaques, five of seven Controls (71.4%) and four of six CR animals (66.7%) expressed minimal to moderate amyloid pathology, and one of six CR animals (16.7%) expressed severe amyloid pathology. That CR affects levels of GFAP expression but not amyloid plaque load provides some insight into the means by which CR is beneficial at the microstructural level, potentially by offsetting the increased load of oxidatively damaged proteins, in this non-human primate model of aging. The present study is a preliminary post-mortem histological analysis of the effects of CR on brain health, and further studies using molecular and biochemical techniques are warranted to elucidate underlying mechanisms. PMID:23473840

Pedophilic sex offenders are characterised by reduced GABA concentration in dorsal anterior cingulate cortex.

PubMed

Ristow, Inka; Li, Meng; Colic, Lejla; Marr, Vanessa; Födisch, Carina; von Düring, Felicia; Schiltz, Kolja; Drumkova, Krasimira; Witzel, Joachim; Walter, Henrik; Beier, Klaus; Kruger, Tillmann H C; Ponseti, Jorge; Schiffer, Boris; Walter, Martin

2018-01-01

A pedophilic disorder is characterised by abnormal sexual urges towards prepubescent children. Child abusive behavior is frequently a result of lack of behavioral inhibition and current treatment options entail, next to suppressing unchangeable sexual orientation, measures to increase cognitive and attentional control. We tested, if in brain regions subserving attentional control of behavior and perception of salient stimuli, such inhibition deficit can be observed also on the level of inhibitory neurotransmitters. We measured GABA concentration in the dorsal anterior cingulate cortex (dACC) and in a control region, the pregenual anterior cingulate cortex (pgACC) in pedophilic sex offenders ( N  = 13) and matched controls ( N  = 13) using a 7 Tesla STEAM magnetic resonance spectroscopy (MRS). In dACC but not in the control region pedophilic sex offenders showed reduced GABA/Cr concentrations compared to healthy controls. The reduction was robust after controlling for potential influence of age and gray matter proportion within the MRS voxel ( p  < 0.04). Importantly, reduced GABA/Cr in patients was correlated with lower self-control measured with the Barratt Impulsiveness Scale (p = 0.028, r = -0.689). In a region related to cognitive control and salience mapping, pedophilic sex offenders showed reduction of the inhibitory neurotransmitter GABA which may be seen as a neuronal correlate of inhibition and behavioral control.

Modulation of Defects in Semiconductors by Facile and Controllable Reduction: The Case of p-type CuCrO2 Nanoparticles.

PubMed

Jiang, Tengfei; Li, Xueyan; Bujoli-Doeuff, Martine; Gautron, Eric; Cario, Laurent; Jobic, Stéphane; Gautier, Romain

2016-08-01

Optical and electrical characteristics of solid materials are well-known to be intimately related to the presence of intrinsic or extrinsic defects. Hence, the control of defects in semiconductors is of great importance to achieve specific properties, for example, transparency and conductivity. Herein, a facile and controllable reduction method for modulating the defects is proposed and used for the case of p-type delafossite CuCrO2 nanoparticles. The optical absorption in the infrared region of the CuCrO2 material can then be fine-tuned via the continuous reduction of nonstoichiometric Cu(II), naturally stabilized in small amounts. This reduction modifies the concentration of positive charge carriers in the material, and thus the conductive and reflective properties, as well as the flat band potential. Indeed, this controllable reduction methodology provides a novel strategy to modulate the (opto-) electronic characteristics of semiconductors.

A comprehensive analysis of three Asiatic black bear mitochondrial genomes (subspecies ussuricus, formosanus and mupinensis), with emphasis on the complete mtDNA sequence of Ursus thibetanus ussuricus (Ursidae).

PubMed

Hwang, Dae-Sik; Ki, Jang-Seu; Jeong, Dong-Hyuk; Kim, Bo-Hyun; Lee, Bae-Keun; Han, Sang-Hoon; Lee, Jae-Seong

2008-08-01

In the present paper, we describe the mitochondrial genome sequence of the Asiatic black bear (Ursus thibetanus ussuricus) with particular emphasis on the control region (CR), and compared with mitochondrial genomes on molecular relationships among the bears. The mitochondrial genome sequence of U. thibetanus ussuricus was 16,700 bp in size with mostly conserved structures (e.g. 13 protein-coding, two rRNA genes, 22 tRNA genes). The CR consisted of several typical conserved domains such as F, E, D, and C boxes, and a conserved sequence block. Nucleotide sequences and the repeated motifs in the CR were different among the bear species, and their copy numbers were also variable according to populations, even within F1 generations of U. thibetanus ussuricus. Comparative analyses showed that the CR D1 region was highly informative for the discrimination of the bear family. These findings suggest that nucleotide sequences of both repeated motifs and CR D1 in the bear family are good markers for species discriminations.

Altered chemical metabolites in the amygdala-hippocampus region contribute to autistic symptoms of autism spectrum disorders.

PubMed

Endo, Taro; Shioiri, Toshiki; Kitamura, Hideaki; Kimura, Teruo; Endo, Sumio; Masuzawa, Naio; Someya, Toshiyuki

2007-11-01

Although several previous studies have been conducted, the neural basis of autism spectrum disorder (ASD) is poorly understood. The objective of the present study was to determine whether individuals with ASD have altered brain chemical metabolites and whether such alterations are related to their autistic symptoms. N-acetylaspartate (NAA)/creatine (Cr) and choline/Cr ratios in the right medial temporal lobe (MTL), medial prefrontal cortex, and cerebellar vermis were measured in 38 individuals with ASD (mean age = 12.9 years), including 12 with autism, 15 with Asperger's Disorder, and 11 with pervasive developmental disorder not otherwise specified (PDD-NOS), and 16 matched healthy control subjects (mean age = 11.5 years) with proton magnetic resonance spectroscopy. Autistic symptoms were assessed by the Childhood Autistic Rating Scale-Tokyo Version. There was a significant group difference for NAA/Cr ratio in the right MTL between the autism, Asperger's Disorder, PDD-NOS, and control groups (p < .001), and the autism group had a significantly lower NAA/Cr ratio compared with the PDD-NOS (p < .001) and control (p < .001) groups. In the ASD group, there was a significant negative correlation between NAA/Cr ratio in the right MTL and their Childhood Autistic Rating Scale-Tokyo Version total scores (r = -.44, p = .01) and subscales of emotional response (r = -.38, p = .02) and listening response (r = -.54, p = .001). The results of the present study suggest that subjects with ASD have abnormalities of neural integrity in the amygdala-hippocampus region that are related to their severity and social impairments.

Main Effects of Diagnoses, Brain Regions, and their Interaction Effects for Cerebral Metabolites in Bipolar and Unipolar Depressive Disorders

NASA Astrophysics Data System (ADS)

Tan, Hai-Zhu; Li, Hui; Liu, Chen-Feng; Guan, Ji-Tian; Guo, Xiao-Bo; Wen, Can-Hong; Ou, Shao-Min; Zhang, Yin-Nan; Zhang, Jie; Xu, Chong-Tao; Shen, Zhi-Wei; Wu, Ren-Hua; Wang, Xue-Qin

2016-11-01

Previous studies suggested patients with bipolar depressive disorder (BDd) or unipolar depressive disorder (UDd) have cerebral metabolites abnormalities. These abnormalities may stem from multiple sub-regions of gray matter in brain regions. Thirteen BDd patients, 20 UDd patients and 20 healthy controls (HC) were enrolled to investigate these abnormalities. Absolute concentrations of 5 cerebral metabolites (glutamate-glutamine (Glx), N-acetylaspartate (NAA), choline (Cho), myo-inositol (mI), creatine (Cr), parietal cortex (PC)) were measured from 4 subregions (the medial frontal cortex (mPFC), anterior cingulate cortex (ACC), posterior cingulate cortex (PCC), and parietal cortex (PC)) of gray matter. Main and interaction effects of cerebral metabolites across subregions of gray matter were evaluated. For example, the Glx was significantly higher in BDd compared with UDd, and so on. As the interaction analyses showed, some interaction effects existed. The concentrations of BDds’ Glx, Cho, Cr in the ACC and HCs’ mI and Cr in the PC were higher than that of other interaction effects. In addition, the concentrations of BDds’ Glx and Cr in the PC and HCs’ mI in the ACC were statistically significant lower than that of other interaction effects. These findings point to region-related abnormalities of cerebral metabolites across subjects with BDd and UDd.

Main Effects of Diagnoses, Brain Regions, and their Interaction Effects for Cerebral Metabolites in Bipolar and Unipolar Depressive Disorders.

PubMed

Tan, Hai-Zhu; Li, Hui; Liu, Chen-Feng; Guan, Ji-Tian; Guo, Xiao-Bo; Wen, Can-Hong; Ou, Shao-Min; Zhang, Yin-Nan; Zhang, Jie; Xu, Chong-Tao; Shen, Zhi-Wei; Wu, Ren-Hua; Wang, Xue-Qin

2016-11-21

Previous studies suggested patients with bipolar depressive disorder (BDd) or unipolar depressive disorder (UDd) have cerebral metabolites abnormalities. These abnormalities may stem from multiple sub-regions of gray matter in brain regions. Thirteen BDd patients, 20 UDd patients and 20 healthy controls (HC) were enrolled to investigate these abnormalities. Absolute concentrations of 5 cerebral metabolites (glutamate-glutamine (Glx), N-acetylaspartate (NAA), choline (Cho), myo-inositol (mI), creatine (Cr), parietal cortex (PC)) were measured from 4 subregions (the medial frontal cortex (mPFC), anterior cingulate cortex (ACC), posterior cingulate cortex (PCC), and parietal cortex (PC)) of gray matter. Main and interaction effects of cerebral metabolites across subregions of gray matter were evaluated. For example, the Glx was significantly higher in BDd compared with UDd, and so on. As the interaction analyses showed, some interaction effects existed. The concentrations of BDds' Glx, Cho, Cr in the ACC and HCs' mI and Cr in the PC were higher than that of other interaction effects. In addition, the concentrations of BDds' Glx and Cr in the PC and HCs' mI in the ACC were statistically significant lower than that of other interaction effects. These findings point to region-related abnormalities of cerebral metabolites across subjects with BDd and UDd.

The degree of peri-implant osteolysis induced by PEEK, CoCrMo, and HXLPE wear particles: a study based on a porous Ti6Al4V implant in a rabbit model.

PubMed

Du, Zhe; Zhu, Zhonglin; Wang, You

2018-01-31

Polyether-ether-ketone (PEEK), cobalt-chromium-molybdenum (CoCrMo), and highly cross-linked polyethylene (HXLPE) are biomaterials used in orthopedic implants; their wear particles are considered to induce peri-implant osteolysis. We examined whether different particle types induce the same degree of peri-implant osteolysis. Forty female rabbits were randomly divided into four groups-the control group (n = 10), which received implantation operation and sham operation at 1 month postoperation; three experimental groups (n = 10 in each group), which received implantation operation along with administration of 0.1 mL of particle suspension (approximately 1.0 × 10 8 PEEK, CoCrMo, or HXLPE wear particles) into the knee joint at 1 month postoperation. All rabbits were sacrificed at 2 months postoperation. The synovium was removed and histologically assessed. The distal femurs with the implants were analyzed via micro-computed tomography (CT) and hard tissue biopsy. The average size of almost 90% of the particles was < 5 μm, indicating no significant difference in the three particle types. IL-1β, IL-8, TNFα, RANKL, and MCP-1 expression in PEEK and CoCrMo groups was high, while that in the HXLPE group was low. The bone density (BD) and bone volume/total volume (BV/TV) of the porous structures (part of the implants in all groups) in experimental groups did not decrease markedly (p > 0.05), while BD in the peripheral regions in experimental groups decreased markedly compared to control groups (p < 0.05). BV/TV in the peripheral regions was significantly decreased in PEEK and CoCrMo groups when compared to control group (p < 0.05), while no significant difference was noted between HXLPE and control groups (p > 0.05). The changes in BV observed in the hard tissue sections were consistent with those noted in the micro-CT findings. PEEK, CoCrMo, and HXLPE wear particles (approximately having the same size and doses) induce peri-implant osteolysis to a different degree: HXLPE particles induce peri-implant osteolysis to a mild degree, while PEEK and CoCrMo particles caused significant peri-implant osteolysis. In case of a porous implant, osteolysis occurred primarily in the peripheral region, rather than in the porous structures. Our findings would be helpful for implant designers to choose friction pairs in orthopedic components.

Neurobiology of the dorsolateral prefrontal cortex in GAD: Aberrant neurometabolic correlation to hippocampus and relationship to anxiety sensitivity and IQ.

PubMed

Coplan, Jeremy D; Webler, Ryan; Gopinath, Srinath; Abdallah, Chadi G; Mathew, Sanjay J

2018-03-15

The neurometabolism underlying the cognitive and affective symptoms associated with generalized anxiety disorder (GAD) remain poorly understood. After we have linked worry to intelligence in patients with GAD, we hypothesized that aberrant neurometabolic correlations between hippocampus and neocortical regions may underlie a shared substrate in GAD patients for both anxiety sensitivity and intelligence. GAD patients (n = 16; F = 11) and healthy volunteers (n = 16; F = 10) were assessed using 1 H-MRSI. Co-axial planes I [hippocampus (HIPP)] and co-axial plane III [dorsolateral prefrontal cortex (DLPFC), central gyrus (CG)] were examined. Using general linear models, we examined resting metabolite concentrations using HIPP as a hub to CG and DLPFC. Neocortical ROIs were related to Anxiety Sensitivity Index (ASI) and Full Scale IQ (FSIQ) in GAD patients versus controls. Right hippocampal Cho/Cr directly predicted left DLPFC Cho/Cr in GAD (r = 0.75), an effect distinguishable (p = 0.0004) from controls. Left HIPP Cho/Cr positively predicted left CG Cho/Cr in GAD, an effect distinguishable from controls. In patients, both left and right DLPFC Cho/Cr positively predicted ASI but only left DLPFC Cho/Cr inversely predicted IQ. By contrast, IQ in controls correlated directly with left CG Cho/Cr. Small sample size precluded us from investigating how gender and FSIQ subscales related to neurochemical correlations in the ROIs examined. Aberrant resting state neurochemical correlation between left DLPFC and right HIPP may contribute to GAD symptomatology. Unlike controls, in GAD, IQ and worry may share a common yet inverse neurometabolic substrate in left DLPFC. Copyright © 2017. Published by Elsevier B.V.

Effect of bimodal harmonic structure design on the deformation behaviour and mechanical properties of Co-Cr-Mo alloy.

PubMed

Vajpai, Sanjay Kumar; Sawangrat, Choncharoen; Yamaguchi, Osamu; Ciuca, Octav Paul; Ameyama, Kei

2016-01-01

In the present work, Co-Cr-Mo alloy compacts with a unique bimodal microstructural design, harmonic structure design, were successfully prepared via a powder metallurgy route consisting of controlled mechanical milling of pre-alloyed powders followed by spark plasma sintering. The harmonic structured Co-Cr-Mo alloy with bimodal grain size distribution exhibited relatively higher strength together with higher ductility as compared to the coarse-grained specimens. The harmonic Co-Cr-Mo alloy exhibited a very complex deformation behavior wherein it was found that the higher strength and the high retained ductility are derived from fine-grained shell and coarse-grained core regions, respectively. Finally, it was observed that the peculiar spatial/topological arrangement of stronger fine-grained and ductile coarse-grained regions in the harmonic structure promotes uniformity of strain distribution, leading to improved mechanical properties by suppressing the localized plastic deformation during straining. Copyright © 2015 Elsevier B.V. All rights reserved.

Assessment of the mutagenic potential of Cr(VI) in the oral mucosa of Big Blue® transgenic F344 rats.

PubMed

Thompson, Chad M; Young, Robert R; Suh, Mina; Dinesdurage, Harshini R; Elbekai, Reem H; Harris, Mark A; Rohr, Annette C; Proctor, Deborah M

2015-08-01

Exposure to high concentrations of hexavalent chromium [Cr(VI)] in drinking water was associated with an increased incidence of oral tumors in F344 rats in a 2-year cancer bioassay conducted by the National Toxicology Program. These tumors primarily occurred at 180 ppm Cr(VI) and appeared to originate from the gingival mucosa surrounding the upper molar teeth. To investigate whether these tumors could have resulted from a mutagenic mode of action (MOA), a transgenic mutation assay based on OECD Test Guideline 488 was conducted in Big Blue(®) TgF344 rats. The mutagenic oral carcinogen 4-nitroquinoline-1-oxide (4-NQO) served as a positive control. Mutant frequency was measured in the inner gingiva with adjacent palate, and outer gingiva with adjacent buccal tissue. Exposure to 10 ppm 4-NQO in drinking water for 28 days increased mutant frequency in the cII transgene significantly, from 39.1 ± 7.5 × 10(-6) to 688 ± 250 × 10(-6) in the gingival/buccal region, and from 49.8 ± 17.8 × 10(-6) to 1818 ± 362 × 10(-6) in the gingival/palate region. Exposure to 180 ppm Cr(VI) in drinking water for 28 days did not significantly increase the mutant frequency in the gingival/buccal (44.4 ± 25.4 × 10(-6)) or the gingival/palate (57.8 ± 9.1 × 10(-6)) regions relative to controls. These data indicate that high (∼180,000 times expected human exposure), tumorigenic concentrations of Cr(VI) did not significantly increase mutations in the gingival epithelium, and suggest that Cr(VI) does not act by a mutagenic MOA in the rat oral cavity. © 2015 Wiley Periodicals, Inc.

Two-dimensional pentagonal CrX (X = S, Se or Te) monolayers: antiferromagnetic semiconductors for spintronics and photocatalysts.

PubMed

Chen, Wenzhou; Kawazoe, Yoshiyuki; Shi, Xingqiang; Pan, Hui

2018-06-25

Two dimensional (2D) materials with hexagonal building blocks have received tremendous interest in recent years and show promise as nanoscale devices for versatile applications. Herein, we propose a new family of 2D pentagonal CrX (X = S, Se or Te) monolayers (penta-CrX) for applications in electronics, spintronics and photocatalysis. We find that the 2D penta-CrX monolayers are thermally, structurally and mechanically stable. The penta-CrX monolayers are antiferromagnetic and semiconducting. We show that the magnetism is attributed to the super-exchange induced by the ionic interactions between the Cr and X atoms and can be enhanced upon applying tension. We further show that the penta-CrS and penta-CrSe monolayers show good redox potentials versus a normal hydrogen electrode, and their band gaps are comparable to the energy of a photon in the visible light region, indicating their capability of maximal utilization of solar energy for water splitting. With intrinsic semiconducting and controllable magnetic properties, the proposed penta-CrX monolayers may hold promise as flexible spintronics and photocatalysts.

Microcosm investigation on phytoremediation of Cr using Azolla pinnata.

PubMed

Rai, Prabhat Kumar

2010-01-01

The extent of Chromium (Cr) pollution in Singrauli industrial region, India was assessed and phytoremediation capacity of a small water fern, Azolla pinnata R.BR (Azollaceae) was observed to purify waters polluted by Cr under microcosm condition. Azolla pinnata endemic to India is a potential hyper-accumulator of heavy metals. During 13 days of the experiment the fern was grown in the aqueous medium containing Cr3+ and CrO4(2-) ions, each in a concentration 0.5, 1.0, and 3.0 mg L(-1). The presence of these ions caused a + 3.1 to -37.5% inhibition of Azolla pinnata growth in comparison to the control. After 13 days of the experiment, metal contents in the solution was decreased up to 70% (CrO4(2-) 3.0 mg L(-1) treatment) to 88% (CrO4(2-) 0.5 mg L(-1) treatment). In the Azolla pinnata tissues, the concentration of couple of the ionic forms of Cr under investigation ranged from 415 to 1095 mg kg(-1) dry mass (dm); the highest level being found for Cr (III) containing solution.

Proton Chemical Shift Imaging of the Brain in Pediatric and Adult Developmental Stuttering.

PubMed

O'Neill, Joseph; Dong, Zhengchao; Bansal, Ravi; Ivanov, Iliyan; Hao, Xuejun; Desai, Jay; Pozzi, Elena; Peterson, Bradley S

2017-01-01

Developmental stuttering is a neuropsychiatric condition of incompletely understood brain origin. Our recent functional magnetic resonance imaging study indicates a possible partial basis of stuttering in circuits enacting self-regulation of motor activity, attention, and emotion. To further characterize the neurophysiology of stuttering through in vivo assay of neurometabolites in suspect brain regions. Proton chemical shift imaging of the brain was performed in a case-control study of children and adults with and without stuttering. Recruitment, assessment, and magnetic resonance imaging were performed in an academic research setting. Ratios of N-acetyl-aspartate plus N-acetyl-aspartyl-glutamate (NAA) to creatine (Cr) and choline compounds (Cho) to Cr in widespread cerebral cortical, white matter, and subcortical regions were analyzed using region of interest and data-driven voxel-based approaches. Forty-seven children and adolescents aged 5 to 17 years (22 with stuttering and 25 without) and 47 adults aged 21 to 51 years (20 with stuttering and 27 without) were recruited between June 2008 and March 2013. The mean (SD) ages of those in the stuttering and control groups were 12.2 (4.2) years and 13.4 (3.2) years, respectively, for the pediatric cohort and 31.4 (7.5) years and 30.5 (9.9) years, respectively, for the adult cohort. Region of interest-based findings included lower group mean NAA:Cr ratio in stuttering than nonstuttering participants in the right inferior frontal cortex (-7.3%; P = .02), inferior frontal white matter (-11.4%; P < .001), and caudate (-10.6%; P = .04), while the Cho:Cr ratio was higher in the bilateral superior temporal cortex (left: +10.0%; P = .03 and right: +10.8%; P = .01), superior temporal white matter (left: +14.6%; P = .003 and right: +9.5%; P = .02), and thalamus (left: +11.6%; P = .002 and right: +11.1%; P = .001). False discovery rate-corrected voxel-based findings were highly consistent with region of interest findings. Additional voxel-based findings in the stuttering sample included higher NAA:Cr and Cho:Cr ratios (regression coefficient, 197.4-275; P < .001) in the posterior cingulate, lateral parietal, hippocampal, and parahippocampal cortices and amygdala, as well as lower NAA:Cr and Cho:Cr ratios (regression coefficient, 119.8-275; P < .001) in the superior frontal and frontal polar cortices. Affected regions comprised nodes of the Bohland speech-production (motor activity regulation), default-mode (attention regulation), and emotional-memory (emotion regulation) networks. Regional correlations were also observed between local metabolites and stuttering severity (r = 0.40-0.52; P = .001-.02). This spectroscopy study of stuttering demonstrates brainwide neurometabolite alterations, including several regions implicated by other neuroimaging modalities. Prior ascription of a role in stuttering to inferior frontal and superior temporal gyri, caudate, and other structures is affirmed. Consistent with prior functional magnetic resonance imaging findings, these results further intimate neurometabolic aberrations in stuttering in brain circuits subserving self-regulation of speech production, attention, and emotion.

Proton Magnetic Resonance Spectroscopy Study on the Metabolism Changes of Cerebellum in Patients with Post-Stroke Depression.

PubMed

Zhang, Lei; Sui, Ru-Bo

2017-01-01

To study the metabolic changes of cerebellum by proton magnetic resonance Spectroscopy (1H-MRS) and discuss the relationships between the cerebellar changes and depression severity in patients with post-stroke depression. Data of demographic characteristics, individual history and life style of all subjects were collected. 40 patients with stroke and 20 controls were enrolled. All groups received T1WI, T2WI, DWI and 1H-MRS examination. The cerebral infarction volume and the distribution and severity of leukoaraiosis were evaluated. The ratios of NAA/Cr, Cho/Cr and Cho/NAA in the cerebellum were calculated. There were no statistical significant difference in the NAA/Cr, Cho/Cr and Cho/NAA ratios in bilateral cerebellum between CONT group and NORM group. The Cho/Cr and Cho/NAA ratios in the cerebellum contralateral to the stroke region were higher in PSD group than those in NORM and CONT groups, and the Cho/Cr and Cho/NAA ratios in the cerebellum ipsilateral to the stroke region were similar with those in NORM and CONT groups. However, there were no statistical significant difference in the NAA/Cr ratios in bilateral cerebellum among three groups. The result shows preliminarily that the cerebellum involves in the development of post-stroke depression. © 2017 The Author(s). Published by S. Karger AG, Basel.

Rice Cellulose SynthaseA8 Plant-Conserved Region Is a Coiled-Coil at the Catalytic Core Entrance1[OPEN

PubMed Central

Rushton, Phillip S.; Olek, Anna T.; Makowski, Lee; Badger, John

2017-01-01

The crystallographic structure of a rice (Oryza sativa) cellulose synthase, OsCesA8, plant-conserved region (P-CR), one of two unique domains in the catalytic domain of plant CesAs, was solved to 2.4 Å resolution. Two antiparallel α-helices form a coiled-coil domain linked by a large extended connector loop containing a conserved trio of aromatic residues. The P-CR structure was fit into a molecular envelope for the P-CR domain derived from small-angle X-ray scattering data. The P-CR structure and molecular envelope, combined with a homology-based chain trace of the CesA8 catalytic core, were modeled into a previously determined CesA8 small-angle X-ray scattering molecular envelope to produce a detailed topological model of the CesA8 catalytic domain. The predicted position for the P-CR domain from the molecular docking models places the P-CR connector loop into a hydrophobic pocket of the catalytic core, with the coiled-coil aligned near the entrance of the substrate UDP-glucose into the active site. In this configuration, the P-CR coiled-coil alone is unlikely to regulate substrate access to the active site, but it could interact with other domains of CesA, accessory proteins, or other CesA catalytic domains to control substrate delivery. PMID:27879387

Insular cortex metabolite changes in obstructive sleep apnea.

PubMed

Yadav, Santosh K; Kumar, Rajesh; Macey, Paul M; Woo, Mary A; Yan-Go, Frisca L; Harper, Ronald M

2014-05-01

Adults with obstructive sleep apnea (OSA) show significant autonomic and neuropsychologic deficits, which may derive from damage to insular regions that serve those functions. The aim was to assess glial and neuronal status from anterior insular metabolites in OSA versus controls, using proton magnetic resonance spectroscopy (PMRS), and thus to provide insights for neuroprotection against tissue changes, and to reduce injury consequences. Cross-sectional study. University-based medical center. Thirty-six patients with OSA, 53 controls. None. We performed PMRS in bilateral anterior insulae using a 3.0-Tesla magnetic resonance imaging scanner, calculated N-acetylaspartate/creatine (NAA/Cr), choline/creatine (Cho/Cr), myo-inositol/creatine (MI/Cr), and MI/NAA metabolite ratios, and examined daytime sleepiness (Epworth Sleepiness Scale, ESS), sleep quality (Pittsburgh Sleep Quality Index, PSQI), and neuropsychologic status (Beck Depression Inventory II [BDI-II] and Beck Anxiety Inventory [BAI]). Body mass index, BAI, BDI-II, PSQI, and ESS significantly differed between groups. NAA/ Cr ratios were significantly reduced bilaterally, and left-sided MI/Cr and MI/NAA ratios were increased in OSA over controls. Significant positive correlations emerged between left insular MI/Cr ratios and apnea-hypopnea index values, right insular Cho/Cr ratios and BDI-II and BAI scores, and negative correlations appeared between left insular NAA/Cr ratios and PSQI scores and between right-side MI/Cr ratios and baseline and nadir change in O2 saturation. Adults with obstructive sleep apnea showed bilaterally reduced N-acetylaspartate and left-side increased myo-inositol anterior insular metabolites, indicating neuronal damage and increased glial activation, respectively, which may contribute to abnormal autonomic and neuropsychologic functions in the condition. The activated glial status likely indicates increased inflammatory action that may induce more neuronal injury, and suggests separate approaches for glial and neuronal protection.

Prognostic Value of p16 Status on the Development of a Complete Response in Involved Oropharynx Cancer Neck Nodes After Cisplatin-Based Chemoradiation: A Secondary Analysis of NRG Oncology RTOG 0129

DOE Office of Scientific and Technical Information (OSTI.GOV)

Galloway, Thomas J., E-mail: thomas.galloway@fccc.edu; Zhang, Qiang; Nguyen-Tan, Phuc Felix

Purpose: To determine the relationship between p16 status and the regional response of patients with node-positive oropharynx cancer treated on NRG Oncology RTOG 0129. Methods and Materials: Patients with N1-N3 oropharynx cancer and known p16 status who underwent treatment on RTOG 0129 were analyzed. Pathologic complete response (pCR) rates in patients treated with a postchemoradiation neck dissection (with p16-positive or p16-negative cancer) were compared by Fisher exact test. Patients managed expectantly were compared with those treated with a neck dissection. Results: Ninety-nine (34%) of 292 patients with node-positive oropharynx cancer and known p16 status underwent a posttreatment neck dissection (p16-positive:more » n=69; p16-negative: n=30). The remaining 193 patients with malignant lymphadenopathy at diagnosis were observed. Neck dissection was performed a median of 70 (range, 17-169) days after completion of chemoradiation. Neither the pretreatment nodal stage (P=.71) nor the postradiation, pre-neck dissection clinical/radiographic neck assessment (P=.42) differed by p16 status. A pCR was more common among p16-positive patients (78%) than p16-negative patients (53%, P=.02) and was associated with a reduced incidence of local–regional failure (hazard ratio 0.33, P=.003). On multivariate analysis of local–regional failure, a test for interaction between pCR and p16 status was not significant (P=.37). One-hundred ninety-three (66%) of 292 of initially node-positive patients were managed without a posttreatment neck dissection. Development of a clinical (cCR) was not significantly influenced by p16-status (P=.42). Observed patients with a clinical nodal CR had disease control outcomes similar to those in patients with a pCR neck dissection. Conclusions: Patients with p16-positive tumors had significantly higher pCR and locoregional control rates than those with p16-negative tumors.« less

Prognostic Value of p16 Status on the Development of a Complete Response in Involved Oropharynx Cancer Neck Nodes After Cisplatin-Based Chemoradiation: A Secondary Analysis of NRG Oncology RTOG 0129.

PubMed

Galloway, Thomas J; Zhang, Qiang Ed; Nguyen-Tan, Phuc Felix; Rosenthal, David I; Soulieres, Denis; Fortin, André; Silverman, Craig L; Daly, Megan E; Ridge, John A; Hammond, J Alexander; Le, Quynh-Thu

2016-10-01

To determine the relationship between p16 status and the regional response of patients with node-positive oropharynx cancer treated on NRG Oncology RTOG 0129. Patients with N1-N3 oropharynx cancer and known p16 status who underwent treatment on RTOG 0129 were analyzed. Pathologic complete response (pCR) rates in patients treated with a postchemoradiation neck dissection (with p16-positive or p16-negative cancer) were compared by Fisher exact test. Patients managed expectantly were compared with those treated with a neck dissection. Ninety-nine (34%) of 292 patients with node-positive oropharynx cancer and known p16 status underwent a posttreatment neck dissection (p16-positive: n=69; p16-negative: n=30). The remaining 193 patients with malignant lymphadenopathy at diagnosis were observed. Neck dissection was performed a median of 70 (range, 17-169) days after completion of chemoradiation. Neither the pretreatment nodal stage (P=.71) nor the postradiation, pre-neck dissection clinical/radiographic neck assessment (P=.42) differed by p16 status. A pCR was more common among p16-positive patients (78%) than p16-negative patients (53%, P=.02) and was associated with a reduced incidence of local-regional failure (hazard ratio 0.33, P=.003). On multivariate analysis of local-regional failure, a test for interaction between pCR and p16 status was not significant (P=.37). One-hundred ninety-three (66%) of 292 of initially node-positive patients were managed without a posttreatment neck dissection. Development of a clinical (cCR) was not significantly influenced by p16-status (P=.42). Observed patients with a clinical nodal CR had disease control outcomes similar to those in patients with a pCR neck dissection. Patients with p16-positive tumors had significantly higher pCR and locoregional control rates than those with p16-negative tumors. Copyright © 2016 Elsevier Inc. All rights reserved.

[Application of local Moran's I and GIS to identify hotspots of Ni, Cr of vegetable soils in high-incidence area of liver cancer from the Pearl River Delta, South China].

PubMed

Li, Yong; Zhou, Yong-Zhang; Zhang, Cheng-Bo; Dou, Lei; Du, Hai-Yan; Lin, Xiao-Ming; Fan, Rui; Du, Min; He, Xiang

2010-06-01

The index of local Moran's I is a useful tool for identifying hotspots of soil Ni and Cr, and for classifying them into spatial clusters and spatial outliers. To identify hotspots of vegetable soils Ni and Cr in high-incidence area of liver cancer, Shunde area of Foshan City, Pearl River Delta Economic Zone, 208 topsoil samples were collected from vegetable fields to measure the contents of nickel (Ni) and chromium (Cr). The results showed that the mean concentrations of two heavy metals Ni, Cr were 33.21 mg/kg, 80.84 mg/kg, respectively, Which were 130%, 60% higher than their soil background values of Guangdong Province, respectively. Generally, Ni is partly accumulated in soil but the accumulation of Cr is not obvious at all. The local Moran's I of Ni and Cr was calculated using 3 000, 6 000, 9 000 m as distance bands, respectively. The hotspots of Ni and Cr elements in soils were identified by local Moran's I which computed based on 6 000 m; "individual hotspots" are in the north which were affected by anthropogenic factors; "regional hotspots" are in the south which were controlled by parent materials. Moreover, the distributions of "regional hotspots" of Ni, Cr are the same as that of the highest mortality rate of liver cancer, this consistence could come up with a research direction that could reveal environmental etiologic factors of liver cancer.

Comparative Mitogenomic Analyses of Praying Mantises (Dictyoptera, Mantodea): Origin and Evolution of Unusual Intergenic Gaps

PubMed Central

Zhang, Hong-Li; Ye, Fei

2017-01-01

Praying mantises are a diverse group of predatory insects. Although some Mantodea mitogenomes have been reported, a comprehensive comparative and evolutionary genomic study is lacking for this group. In the present study, four new mitogenomes were sequenced, annotated, and compared to the previously published mitogenomes of other Mantodea species. Most Mantodea mitogenomes share a typical set of mitochondrial genes and a putative control region (CR). Additionally, and most intriguingly, another large non-coding region (LNC) was detected between trnM and ND2 in all six Paramantini mitogenomes examined. The main section in this common region of Paramantini may have initially originated from the corresponding control region for each species, whereas sequence differences between the LNCs and CRs and phylogenetic analyses indicate that LNC and CR are largely independently evolving. Namely, the LNC (the duplicated CR) may have subsequently degenerated during evolution. Furthermore, evidence suggests that special intergenic gaps have been introduced in some species through gene rearrangement and duplication. These gaps are actually the original abutting sequences of migrated or duplicated genes. Some gaps (G5 and G6) are homologous to the 5' and 3' surrounding regions of the duplicated gene in the original gene order, and another specific gap (G7) has tandem repeats. We analysed the phylogenetic relationships of fifteen Mantodea species using 37 concatenated mitochondrial genes and detected several synapomorphies unique to species in some clades. PMID:28367101

Non-Chromate/No-VOC Coating System for DoD Applications

DTIC Science & Technology

2009-03-31

chromium species, at which point the corrosion protection capabilities suffer. Cr6+ is used everywhere that self - healing corrosion protection is...surface region in which the Cr6+ remains, forming a self - healing chemistry that re-protects if scratched. Thin (Class 3) chromate conversion layers are...olation polymer control color, thickness, and the self - healing property of the film [7]. TCP does not contain any free trivalent chromium and is free of

Complete mitochondrial genome of Platevindex sp. (Gastropoda: Pulmonata: Systellommatophora: Onchidiidae).

PubMed

Liu, Chen; Shen, He Ding; Zhou, Na

2016-01-01

The complete mitochondrial genome sequence of Platevindex sp. is firstly described in the article. The mitogenome (13,908 bp) contains 22 tRNA genes, 2 ribosomal RNA genes and 13 protein-coding genes, and 1 putative control region (CR). CR is not well characterized due to lack of discrete conserved sequence blocks. This characteristic is similar with CRs of other invertebrate mitochondrial genomes. The characteristic is the typical bivalvia mitochondrial gene composition.

Role of diffusion tensor imaging or magnetic resonance spectroscopy in the diagnosis and disability assessment of amyotrophic lateral sclerosis.

PubMed

Liu, Chanchan; Jiang, Rifeng; Yi, Xiyan; Zhu, Wenzhen; Bu, Bitao

2015-01-15

To compare the results of magnetic resonance spectroscopy (MRS) and diffusion tensor imaging (DTI) in amyotrophic lateral sclerosis (ALS) patients. Nineteen ALS patients and thirteen age-matched healthy controls underwent MRS and DTI between October 2013 and July 2014. Fractional anisotropy (FA), apparent diffusion coefficient (ADC), N-acetylaspartate (NAA), choline (Cho), and creatine (Cr) were collected as the quantitative results of the imaging study. The ALS functional rating scale-revised (ALSFRS-R) and disease progression rate were evaluated to assess patients' disability. The imaging study results were compared between ALS patients and healthy controls. The relationship between disability assessment and imaging study results was analyzed. NAA/Cr in the motor cortex and FA in the corticospinal tract (CST) of both sides were significantly lower in patients than controls. There was no significant difference between the two groups in Cho/Cr, tract length, tract volume, ADC or NAA. No relationship was found between ALSFRS-R and FA (r=0.243, p=0.316) in the right CST; NAA (r=0.095, p=0.699) or NAA/Cr (r=0.172, p=0.481) in the left motor cortex; or NAA (r=0.320, p=0.182) or NAA/Cr (r=0.193, p=0.492) in the right motor cortex. There was no relationship between the disease progression rate and FA, NAA, or NAA/Cr on either side. NAA/Cr and FA can help diagnose ALS. Regional brain NAA/Cr and FA values could not assess the ALSFRS-R or disease progression rate. Copyright © 2014 Elsevier B.V. All rights reserved.

Magnetic Resonance T2-Relaxometry and 2D L-Correlated Spectroscopy in Patients with Minimal Hepatic Encephalopathy

PubMed Central

Singhal, Aparna; Nagarajan, Rajakumar; Kumar, Rajesh; Huda, Amir; Gupta, Rakesh K.; Thomas, M. Albert

2010-01-01

Purpose To evaluate T2-relaxation changes in patients with minimal hepatic encephalopathy (MHE) using T2-relaxometry and to correlate T2 values with brain metabolites evaluated using two-dimensional (2D) magnetic resonance spectroscopy (MRS). Materials and Methods Eight MHE patients and 13 healthy subjects were evaluated using T2-relaxometry, and 8 patients and 9 healthy subjects underwent 2D MRS in right frontal and left occipital regions. Whole brain T2-relaxation maps were compared between MHE and control subjects using analysis-of-covariance, with age and gender included as covariates. T2 values derived from the right frontal and left occipital lobes were correlated with the metabolite ratios. Results Multiple brain regions including anterior and mid cingulate cortices, right anterior and left posterior insular cortices, right prefrontal, medial frontal, and right superior temporal cortices showed significantly increased T2 values in MHE patients compared to control subjects. MRS showed significantly increased ratios of glutamine/glutamate (Glx) and decreased ratios of myo-inositol, taurine, choline, and myo-inositol/choline (mICh) with respect to creatine (Cr_d) in patients compared to controls. Frontal Glx/Cr_d showed significantly positive correlation with T2 values. Conclusion MHE patients showed significantly increased T2 values in multiple brain regions reflecting increased free water content and T2 values in frontal lobe correlated with the increased Glx/Cr_d ratio. PMID:19856435

Effect of Annealing Process on the Properties of Ni(55%)Cr(40%)Si(5%) Thin-Film Resistors

PubMed Central

Cheng, Huan-Yi; Chen, Ying-Chung; Li, Pei-Jou; Yang, Cheng-Fu; Huang, Hong-Hsin

2015-01-01

Resistors in integrated circuits (ICs) are implemented using diffused methods fabricated in the base and emitter regions of bipolar transistor or in source/drain regions of CMOS. Deposition of thin films on the wafer surface is another choice to fabricate the thin-film resistors in ICs’ applications. In this study, Ni(55%)Cr(40%)Si(5%) (abbreviated as NiCrSi) in wt % was used as the target and the sputtering method was used to deposit the thin-film resistors on Al2O3 substrates. NiCrSi thin-film resistors with different thicknesses of 30.8 nm~334.7 nm were obtained by controlling deposition time. After deposition, the thin-film resistors were annealed at 400 °C under different durations in N2 atmosphere using the rapid thermal annealing (RTA) process. The sheet resistance of NiCrSi thin-film resistors was measured using the four-point-probe method from 25 °C to 125 °C, then the temperature coefficient of resistance could be obtained. We aim to show that resistivity of NiCrSi thin-film resistors decreased with increasing deposition time (thickness) and the annealing process had apparent effect on the sheet resistance and temperature coefficient of resistance. We also aim to show that the annealed NiCrSi thin-film resistors had a low temperature coefficient of resistance (TCR) between 0 ppm/°C and +50 ppm/°C. PMID:28793598

Effect of Annealing Process on the Properties of Ni(55%)Cr(40%)Si(5%) Thin-Film Resistors.

PubMed

Cheng, Huan-Yi; Chen, Ying-Chung; Li, Pei-Jou; Yang, Cheng-Fu; Huang, Hong-Hsin

2015-10-02

Resistors in integrated circuits (ICs) are implemented using diffused methods fabricated in the base and emitter regions of bipolar transistor or in source/drain regions of CMOS. Deposition of thin films on the wafer surface is another choice to fabricate the thin-film resistors in ICs' applications. In this study, Ni(55%)Cr(40%)Si(5%) (abbreviated as NiCrSi) in wt % was used as the target and the sputtering method was used to deposit the thin-film resistors on Al2O3 substrates. NiCrSi thin-film resistors with different thicknesses of 30.8 nm~334.7 nm were obtained by controlling deposition time. After deposition, the thin-film resistors were annealed at 400 °C under different durations in N₂ atmosphere using the rapid thermal annealing (RTA) process. The sheet resistance of NiCrSi thin-film resistors was measured using the four-point-probe method from 25 °C to 125 °C, then the temperature coefficient of resistance could be obtained. We aim to show that resistivity of NiCrSi thin-film resistors decreased with increasing deposition time (thickness) and the annealing process had apparent effect on the sheet resistance and temperature coefficient of resistance. We also aim to show that the annealed NiCrSi thin-film resistors had a low temperature coefficient of resistance (TCR) between 0 ppm/°C and +50 ppm/°C.

Complement receptor 1 variants confer protection from severe malaria in Odisha, India.

PubMed

Panda, Aditya K; Panda, Madhumita; Tripathy, Rina; Pattanaik, Sarit S; Ravindran, Balachandran; Das, Bidyut K

2012-01-01

In Plasmodium falciparum infection, complement receptor-1 (CR1) on erythrocyte's surface and ABO blood group play important roles in formation of rosettes which are presumed to be contributory in the pathogenesis of severe malaria. Although several studies have attempted to determine the association of CR1 polymorphisms with severe malaria, observations remain inconsistent. Therefore, a case control study and meta-analysis was performed to address this issue. Common CR1 polymorphisms (intron 27 and exon 22) and blood group were typed in 353 cases of severe malaria (SM) [97 cerebral malaria (CM), 129 multi-organ dysfunction (MOD), 127 non-cerebral severe malaria (NCSM)], 141 un-complicated malaria and 100 healthy controls from an endemic region of Odisha, India. Relevant publications for meta-analysis were searched from the database. The homozygous polymorphisms of CR1 intron 27 and exon 22 (TT and GG) and alleles (T and G) that are associated with low expression of CR1 on red blood cells, conferred significant protection against CM, MOD and malaria deaths. Combined analysis showed significant association of blood group B/intron 27-AA/exon 22-AA with susceptibility to SM (CM and MOD). Meta-analysis revealed that the CR1 exon 22 low expression polymorphism is significantly associated with protection against severe malaria. The results of the present study demonstrate that common CR1 variants significantly protect against severe malaria in an endemic area.

Recombination and evolution of duplicate control regions in the mitochondrial genome of the Asian big-headed turtle, Platysternon megacephalum.

PubMed

Zheng, Chenfei; Nie, Liuwang; Wang, Jue; Zhou, Huaxing; Hou, Huazhen; Wang, Hao; Liu, Juanjuan

2013-01-01

Complete mitochondrial (mt) genome sequences with duplicate control regions (CRs) have been detected in various animal species. In Testudines, duplicate mtCRs have been reported in the mtDNA of the Asian big-headed turtle, Platysternon megacephalum, which has three living subspecies. However, the evolutionary pattern of these CRs remains unclear. In this study, we report the completed sequences of duplicate CRs from 20 individuals belonging to three subspecies of this turtle and discuss the micro-evolutionary analysis of the evolution of duplicate CRs. Genetic distances calculated with MEGA 4.1 using the complete duplicate CR sequences revealed that within turtle subspecies, genetic distances between orthologous copies from different individuals were 0.63% for CR1 and 1.2% for CR2app:addword:respectively, and the average distance between paralogous copies of CR1 and CR2 was 4.8%. Phylogenetic relationships were reconstructed from the CR sequences, excluding the variable number of tandem repeats (VNTRs) at the 3' end using three methods: neighbor-joining, maximum likelihood algorithm, and Bayesian inference. These data show that any two CRs within individuals were more genetically distant from orthologous genes in different individuals within the same subspecies. This suggests independent evolution of the two mtCRs within each P. megacephalum subspecies. Reconstruction of separate phylogenetic trees using different CR components (TAS, CD, CSB, and VNTRs) suggested the role of recombination in the evolution of duplicate CRs. Consequently, recombination events were detected using RDP software with break points at ≈290 bp and ≈1,080 bp. Based on these results, we hypothesize that duplicate CRs in P. megacephalum originated from heterological ancestral recombination of mtDNA. Subsequent recombination could have resulted in homogenization during independent evolutionary events, thus maintaining the functions of duplicate CRs in the mtDNA of P. megacephalum.

Recombination and Evolution of Duplicate Control Regions in the Mitochondrial Genome of the Asian Big-Headed Turtle, Platysternon megacephalum

PubMed Central

Zheng, Chenfei; Nie, Liuwang; Wang, Jue; Zhou, Huaxing; Hou, Huazhen; Wang, Hao; Liu, Juanjuan

2013-01-01

Complete mitochondrial (mt) genome sequences with duplicate control regions (CRs) have been detected in various animal species. In Testudines, duplicate mtCRs have been reported in the mtDNA of the Asian big-headed turtle, Platysternon megacephalum, which has three living subspecies. However, the evolutionary pattern of these CRs remains unclear. In this study, we report the completed sequences of duplicate CRs from 20 individuals belonging to three subspecies of this turtle and discuss the micro-evolutionary analysis of the evolution of duplicate CRs. Genetic distances calculated with MEGA 4.1 using the complete duplicate CR sequences revealed that within turtle subspecies, genetic distances between orthologous copies from different individuals were 0.63% for CR1 and 1.2% for CR2app:addword:respectively, and the average distance between paralogous copies of CR1 and CR2 was 4.8%. Phylogenetic relationships were reconstructed from the CR sequences, excluding the variable number of tandem repeats (VNTRs) at the 3′ end using three methods: neighbor-joining, maximum likelihood algorithm, and Bayesian inference. These data show that any two CRs within individuals were more genetically distant from orthologous genes in different individuals within the same subspecies. This suggests independent evolution of the two mtCRs within each P. megacephalum subspecies. Reconstruction of separate phylogenetic trees using different CR components (TAS, CD, CSB, and VNTRs) suggested the role of recombination in the evolution of duplicate CRs. Consequently, recombination events were detected using RDP software with break points at ≈290 bp and ≈1,080 bp. Based on these results, we hypothesize that duplicate CRs in P. megacephalum originated from heterological ancestral recombination of mtDNA. Subsequent recombination could have resulted in homogenization during independent evolutionary events, thus maintaining the functions of duplicate CRs in the mtDNA of P. megacephalum. PMID:24367563

High Incidence of Malaria Along the Sino-Burmese Border Is Associated With Polymorphisms of CR1, IL-1A, IL-4R, IL-4, NOS, and TNF, But Not With G6PD Deficiency.

PubMed

Ren, Na; Kuang, Ying-Min; Tang, Qiong-Lin; Cheng, Long; Zhang, Chun-Hua; Yang, Zao-Qing; He, Yong-Shu; Zhu, Yue-Chun

2015-10-01

Malaria is highly endemic in Yunnan Province, China, with the incidence of malaria being highest along the Sino-Burmese border. The aim of our study was to determine whether genetic polymorphisms are associated with the prevalence of malaria among Chinese residents of the Sino-Burmese border region. Fourteen otherwise healthy people with glucose-6-phosphate dehydrogenase (G6PD) deficiency, 50 malaria patients, and 67 healthy control subjects were included in our cross-sectional study. We analyzed the frequency of the G3093T and T520C single-nucleotide polymorphisms (SNPs) of CR1. Logistic regression was used to calculate the prevalence odds ratio (POR) and 95% confidence interval (CI) of malaria for the T520C SNP of CR1 and SNPs of G6PD, IL-4, IL-4R, IL-1A, NOS, CD40LG, TNF, and LUC7L. The frequency of the 3093T/3093T genotype of CR1 in the malaria group (0.16) was significantly higher than that in the control group (0.045, P < 0.05), and significantly lower than that in the G6PD deficiency group (0.43, P < 0.01). The frequency of the 520T/520T genotype of CR1 was significantly higher in the malaria patients (0.78) than that in the control group (0.67, P < 0.05) and G6PD-deficiency group (0.36, P < 0.05). The T allele of the T520C variant of CR1 was significantly associated with the prevalence of malaria (POR: 1.460; 95% CI: 0.703-3.034). Polymorphisms of G6PD did not significantly influence the prevalence malaria (P > 0.05). A GTGTGTC haplotype consisting of IL-1A (rs17561), IL-4 (rs2243250), TNF (rs1800750), IL-4R (rs1805015), NOS (rs8078340), CD40LG (rs1126535), and LUC7L (rs1211375) was significantly associated with the prevalence of malaria (POR: 1.822, 95% CI: 0.998-3.324). The 3093G/3093G and 520T/520T genotypes are the predominant genetic variants of CR1 among Chinese residents near the Sino-Burmese border, and the T allele of T520C is associated with the prevalence of malaria in this region. Although G6PD deficiency does not protect against malaria, it may diminish the association between malaria and the CR1 polymorphisms in this population. The GTGTGTC haplotype is also associated with the prevalence of malaria in this region.

A plan for study of hexavalent chromium, CR(VI) in groundwater near a mapped plume, Hinkley, California, 2016

USGS Publications Warehouse

Izbicki, John A.; Groover, Krishangi D.

2016-01-22

The Pacific Gas and Electric Company (PG&E) Hinkley compressor station, in the Mojave Desert 80 miles northeast of Los Angeles, is used to compress natural gas as it is transported through a pipeline from Texas to California. Between 1952 and 1964, cooling water used at the compressor station was treated with a compound containing chromium to prevent corrosion. After cooling, the wastewater was discharged to unlined ponds, resulting in contamination of soil and groundwater in the underlying alluvial aquifer (Lahontan Regional Water Quality Control Board, 2013). Since 1964, cooling-water management practices have been used that do not contribute chromium to groundwater.In 2007, a PG&E study of the natural background concentrations of hexavalent chromium, Cr(VI), in groundwater estimated average concentrations in the Hinkley area to be 1.2 micrograms per liter (μg/L), with a 95-percent upper-confidence limit of 3.1 μg/L (CH2M-Hill, 2007). The 3.1 μg/L upper-confidence limit was adopted by the Lahontan Regional Water Quality Control Board (RWQCB) as the maximum background concentration used to map the plume extent. In response to criticism of the study’s methodology, and an increase in the mapped extent of the plume between 2008 and 2011, the Lahontan RWQCB (Lahontan Regional Water Quality Control Board, 2012) agreed that the 2007 PG&E background-concentration study be updated.The purpose of the updated background study is to evaluate the presence of natural and man-made Cr(VI) near Hinkley, Calif. The study also is to estimate natural background Cr(VI) concentrations in the aquifer upgradient and downgradient from the mapped Cr(VI) contamination plume, as well as in the plume and near its margins. The study was developed by the U.S. Geological Survey (USGS) in collaboration with a technical working group (TWG) composed of community members, the Independent Review Panel (IRP) Manager (Project Navigator, Ltd.), the Lahontan RWQCB, PG&E, and consultants for PG&E.&E.

A regional-scale study of chromium and nickel in soils of northern California, USA

USGS Publications Warehouse

Morrison, J.M.; Goldhaber, M.B.; Lee, L.; Holloway, J.M.; Wanty, R.B.; Wolf, R.E.; Ranville, J.F.

2009-01-01

A soil geochemical survey was conducted in a 27,000-km2 study area of northern California that includes the Sierra Nevada Mountains, the Sacramento Valley, and the northern Coast Range. The results show that soil geochemistry in the Sacramento Valley is controlled primarily by the transport and weathering of parent material from the Coast Range to the west and the Sierra Nevada to the east. Chemically and mineralogically distinctive ultramafic (UM) rocks (e.g. serpentinite) outcrop extensively in the Coast Range and Sierra Nevada. These rocks and the soils derived from them have elevated concentrations of Cr and Ni. Surface soil samples derived from UM rocks of the Sierra Nevada and Coast Range contain 1700-10,000 mg/kg Cr and 1300-3900 mg/kg Ni. Valley soils west of the Sacramento River contain 80-1420 mg/kg Cr and 65-224 mg/kg Ni, reflecting significant contributions from UM sources in the Coast Range. Valley soils on the east side contain 30-370 mg/kg Cr and 16-110 mg/kg Ni. Lower Cr and Ni concentrations on the east side of the valley are the result of greater dilution by granitic sources of the Sierra Nevada. Chromium occurs naturally in the Cr(III) and Cr(VI) oxidation states. Trivalent Cr is a non-toxic micronutrient, but Cr(VI) is a highly soluble toxin and carcinogen. X-ray diffraction and scanning electron microscopy of soils with an UM parent show Cr primarily occurs within chromite and other mixed-composition spinels (Al, Mg, Fe, Cr). Chromite contains Cr(III) and is highly refractory with respect to weathering. Comparison of a 4-acid digestion (HNO3, HCl, HF, HClO4), which only partially dissolves chromite, and total digestion by lithium metaborate (LiBO3) fusion, indicates a lower proportion of chromite-bound Cr in valley soils relative to UM source soils. Groundwater on the west side of the Sacramento Valley has particularly high concentrations of dissolved Cr ranging up to 50 ??g L-1 and averaging 16.4 ??g L-1. This suggests redistribution of Cr during weathering and oxidation of Cr(III)-bearing minerals. It is concluded that regional-scale transport and weathering of ultramafic-derived constituents have resulted in enrichment of Cr and Ni in the Sacramento Valley and a partial change in the residence of Cr.

Microstructure of Vacuum-Brazed Joints of Super-Ni/NiCr Laminated Composite Using Nickel-Based Amorphous Filler Metal

NASA Astrophysics Data System (ADS)

Ma, Qunshuang; Li, Yajiang; Wu, Na; Wang, Juan

2013-06-01

Vacuum brazing of super-Ni/NiCr laminated composite and Cr18-Ni8 stainless steel was carried out using Ni-Cr-Si-B amorphous filler metal at 1060, 1080, and 1100 °C, respectively. Microstructure and phase constitution were investigated by means of optical and scanning electron microscopy, energy-dispersive spectroscopy, x-ray diffraction, and micro-hardness tester. When brazed at 1060-1080 °C, the brazed region can be divided into two distinct zones: isothermally solidified zone (ISZ) consisting of γ-Ni solid solution and athermally solidified zone (ASZ) consisting of Cr-rich borides. Micro-hardness of the Cr-rich borides formed in the ASZ was as high as 809 HV50 g. ASZ decreased with increase of the brazing temperature. Isothermal solidification occurred sufficiently at 1100 °C and an excellent joint composed of γ-Ni solid solution formed. The segregation of boron from ISZ to residual liquid phase is the reason of Cr-rich borides formed in ASZ. The formation of secondary precipitates in diffusion-affected zone is mainly controlled by diffusion of B.

[How does the Regional Psychiatry Budget (RPB) work in an area with initially low capacity of psychiatric hospital beds?].

PubMed

König, Hans-Helmut; Heider, Dirk; Rechlin, Thomas; Hoffmann, Peter; Birker, Thomas; Heinrich, Sven; Brettschneider, Christian; Hierholzer, Cornelia; Riedel-Heller, Steffi G; Roick, Christiane

2013-11-01

To analyze the impact of a capitated multi-sector-financing model for psychiatric care (RPB) in the model region Rendsburg-Eckernförde on costs and effectiveness of care. In a prospective controlled cohort study 244 patients with a diagnosis according to ICD-10: F10, F2 or F3 were interviewed in the model region (MR) and compared to 244 patients from a control region (CR) financed according to the fee-for-service principle. At baseline, 1.5 years and 3.5 years follow-up patients were interviewed using measures of psychopathology (CGI-S, HONOS, SCL-90 R/GSI, PANSS, BRMAS/BRMES), functioning (GAF, SOFAS), quality of life (EQ-5 D) and service use/costs (CSSRI). Subjective symptom severity (GSI) and functioning (GAF) developed more favourably in the MR than in the CR, the HONOS score developed slightly worse in the MR. The latter effect occurred mainly in ICD-10: F10 patients, while patients with F2/3 rather did benefit under RPB conditions. The development of total costs of care was not different between MR and CR. The potential to reduce costs of in-patient care was low due to the initially low capacity of inpatient beds. The RPB did not reduce the total costs of mental health care, but certain diagnosis groups may benefit from improved trans-sectoral treatment flexibility. © Georg Thieme Verlag KG Stuttgart · New York.

Distinct effects of Cr bulk doping and surface deposition on the chemical environment and electronic structure of the topological insulator Bi2Se3

NASA Astrophysics Data System (ADS)

Yilmaz, Turgut; Hines, William; Sun, Fu-Chang; Pletikosić, Ivo; Budnick, Joseph; Valla, Tonica; Sinkovic, Boris

2017-06-01

In this report, it is shown that Cr doped into the bulk and Cr deposited on the surface of Bi2Se3 films produced by molecular beam epitaxy (MBE) have strikingly different effects on both the electronic structure and chemical environment. Angle resolved photoemission spectroscopy (ARPES) shows that Cr doped into the bulk opens a surface state energy gap which can be seen at room temperature; much higher than the measured ferromagnetic transition temperature of ≈10 K. On the other hand, similar ARPES measurements show that the surface states remain gapless down to 15 K for films with Cr surface deposition. In addition, core-level photoemission spectroscopy of the Bi 5d, Se 3d, and Cr 3p core levels show distinct differences in the chemical environment for the two methods of Cr introduction. Surface deposition of Cr results in the formation of shoulders on the lower binding energy side for the Bi 5d peaks and two distinct Cr 3p peaks indicative of two Cr sites. These striking differences suggests an interesting possibility that better control of doping at only near surface region may offer a path to quantum anomalous Hall states at higher temperatures than reported in the literature.

Insular Cortex Metabolite Changes in Obstructive Sleep Apnea

PubMed Central

Yadav, Santosh K.; Kumar, Rajesh; Macey, Paul M.; Woo, Mary A.; Yan-Go, Frisca L.; Harper, Ronald M.

2014-01-01

Study Objective: Adults with obstructive sleep apnea (OSA) show significant autonomic and neuropsychologic deficits, which may derive from damage to insular regions that serve those functions. The aim was to assess glial and neuronal status from anterior insular metabolites in OSA versus controls, using proton magnetic resonance spectroscopy (PMRS), and thus to provide insights for neuroprotection against tissue changes, and to reduce injury consequences. Design: Cross-sectional study. Setting: University-based medical center. Participants: Thirty-six patients with OSA, 53 controls. Interventions: None. Measurements and Results: We performed PMRS in bilateral anterior insulae using a 3.0-Tesla magnetic resonance imaging scanner, calculated N-acetylaspartate/creatine (NAA/Cr), choline/creatine (Cho/Cr), myo-inositol/creatine (MI/Cr), and MI/NAA metabolite ratios, and examined daytime sleepiness (Epworth Sleepiness Scale, ESS), sleep quality (Pittsburgh Sleep Quality Index, PSQI), and neuropsychologic status (Beck Depression Inventory II [BDI-II] and Beck Anxiety Inventory [BAI]). Body mass index, BAI, BDI-II, PSQI, and ESS significantly differed between groups. NAA/ Cr ratios were significantly reduced bilaterally, and left-sided MI/Cr and MI/NAA ratios were increased in OSA over controls. Significant positive correlations emerged between left insular MI/Cr ratios and apnea-hypopnea index values, right insular Cho/Cr ratios and BDI-II and BAI scores, and negative correlations appeared between left insular NAA/Cr ratios and PSQI scores and between right-side MI/Cr ratios and baseline and nadir change in O2 saturation. Conclusions: Adults with obstructive sleep apnea showed bilaterally reduced N-acetylaspartate and left-side increased myo-inositol anterior insular metabolites, indicating neuronal damage and increased glial activation, respectively, which may contribute to abnormal autonomic and neuropsychologic functions in the condition. The activated glial status likely indicates increased inflammatory action that may induce more neuronal injury, and suggests separate approaches for glial and neuronal protection. Citation: Yadav SK, Kumar R, Macey PM, Woo MA, Yan-Go FL, Harper RM. Insular cortex metabolite changes in obstructive sleep apnea. SLEEP 2014;37(5):951-958. PMID:24790274

Effect of occupational manganese exposure on the central nervous system of welders: 1H magnetic resonance spectroscopy and MRI findings.

PubMed

Kim, Eun A; Cheong, Hae-Kwan; Choi, Dae Seob; Sakong, Joon; Ryoo, Jae Wook; Park, Injeong; Kang, Dong Mug

2007-03-01

This study investigated the relationship between long-term occupational manganese (Mn) exposure on the regional Mn concentration in the brain, neuronal loss, and neurobehavioral effects on welders. 1H MRS of the basal ganglia (BG) was performed on 20 male welders and 10 age- and gender-matched, non-office, control workers in a shipyard to assess the metabolic change, and the N-acetylaspartate (NAA)/creatine (Cr), choline (Cho)/Cr and NAA/Cho ratios, by the level of Mn exposure. We also assessed the signal intensity of T1-weighted image of magnetic resonance imaging (MRI) on globus pallidus (GP) compared to that of the frontal white matter (pallidal index, PI). The welders had significantly higher signal intensity than the controls. PI showed a significant dose-response relationship with cumulative exposure index (CEI) (r=0.54, p=0.002). CEI and PI showed different relationships with NAA/Cr according to smoking status, and the correlation was evident only in non-smokers (r=-0.73 and -0.57, respectively). There were no significant differences between the welders and the controls in NAA/Cr, Cho/Cr, and NAA/Cho ratios obtained from BG. CEI was positively correlated with simple reaction time. PI was positively correlated with mean sway (MSWAY), sway area (SWAYA), and sway intensity (SWAYI), and negatively correlated with maximum frequency (MAXF). After categorizing the subjects into two groups according to NAA/Cr ratio level, the low NAA/Cr ratio group showed significantly lower score on digit span backward and significantly higher score on MSWAY, SWAYA and SWAYI in regression analysis than the high NAA/Cr ratio group. We speculated that the NAA/Cr ratio of MRS in BG seems to reflect the cumulative effect of Mn exposure on the human brain. Due to uneven distribution of smoking among the welders and the controls, in addition to the small number of subjects in our study, our findings are needed further studies with a larger number of subjects.

Magnetic resonance spectroscopy findings in photosensitive idiopathic generalized epilepsy.

PubMed

Aydin-Ozemir, Zeynep; Terzibasioglu, Ege; Altindag, Ebru; Sencer, Serra; Baykan, Betul

2010-01-01

Studies investigating the pathophysiology of epileptic photosensitivity indicate variable involvement of particular brain regions. Our aim was to identify metabolic differences between photosensitive idiopathic generalized epilepsy (IGE) patients and nonphotosensitive IGE patients and normal healthy subjects by using Magnetic Resonance Spectroscopy (MRS). Fourteen patients diagnosed with photosensitive IGE were investigated. The control groups consisted of 14 age- and sex-matched healthy volunteers and 14 IGE patients without photosensitivity. MRS measurements of N-acetylaspartate (NAA), choline-containing compounds (Cho), creatine (Cr) were performed in the frontal and occipital cortex and the thalamus bilaterally using a stimulated echo acquisition mode (STEAM) technique with a voxel size of 20 x 20 x 20 mm. The values of the patients with IGE were compared with those of the normal controls and within subgroups according to the clinical variables by appropriate statistical tests. Photosensitive IGE patients showed significantly decreased concentrations of NAA in the right frontal lobe and left thalamus, decreased NAA/Cr ratio in left thalamus and significantly increased concentrations of Cho/Cr ratio in the right frontal lobe and NAA/Cr in the left occipital lobe when compared to normal controls. Furthermore, left occipital NAA concentration increased and left thalamus NAA/Cr ratios were decreased from the IGE patients without photosensitivity but without reaching statistical significance. Our results support previous MR studies suggesting an asymmetrical neuronal dysfunction in favor of the dominant occipital cortex and thalamus in photosensitive IGE patients.

Health consumption in Sami speaking municipalities and a control group with regard to medical imaging.

PubMed

Størmer, Jan; Norum, Jan; Olsen, Lena Ringstad; Eldevik, Petter; Broderstad, Ann Ragnhild

2012-03-23

The Northern Norway Regional Health Authority trust aims to offer a high quality specialist health care to all inhabitants. The objective of this study was to document the consumption of medical imaging [conventional radiography (CR), computerised tomography (CT), magnetic resonance (MR), ultrasound (US)]. The eight municipalities in northern Norway included in the administration area of the Sami language law (Sami group - 132,490 persons/year in the period 2003-2009, mean/year 19,363 inhabitants) were matched with a control group of 11 municipalities (non-Sami group - 135,539 persons/year, mean/year 18,927 inhabitants). Population data was accessed from Statistics Norway. Data on imaging exams were derived from a regional database including production data from all public and private institutions within the region. All four main modality groups (CR, CT, MR, US) were analysed. Variations for imaging frequency on each modality were compared between the Sami and non-Sami municipalities. A total of 278,832 exams were performed during study period. The age adjusted exam rate (all modalities) was significantly higher (p < 0.001) in non-Sami (females and males) group. There was no difference with regard to conventional radiography (CR) (p = 0.855). Whereas MR (p < 0.001) imaging was more common in the Sami group, CT (p < 0.001) and US (p = 0.003) exams were more frequently used in the control group. People living in Sami speaking communities experienced significantly less CT and US exams, but had more MR exams than the control group. A relatively high physical activity, obesity and a lower risk of cancer may be explanations.

Health consumption in Sami speaking municipalities and a control group with regard to medical imaging.

PubMed

Størmer, Jan; Norum, Jan; Olsen, LenaRingstad; Eldevik, Petter; Ragnhild Broderstad, Ann

2012-01-01

The Northern Norway Regional Health Authority trust aims to offer a high quality specialist health care to all inhabitants. The objective of this study was to document the consumption of medical imaging [conventional radiography (CR), computerised tomography (CT), magnetic resonance (MR), ultrasound (US)]. The eight municipalities in northern Norway included in the administration area of the Sami language law (Sami group - 132,490 persons/year in the period 2003-2009, mean/year 19,363 inhabitants) were matched with a control group of 11 municipalities (non-Sami group - 135,539 persons/year, mean/year 18,927 inhabitants). Population data was accessed from Statistics Norway. Data on imaging exams were derived from a regional database including production data from all public and private institutions within the region. All four main modality groups (CR, CT, MR, US) were analysed. Variations for imaging frequency on each modality were compared between the Sami and non-Sami municipalities. A total of 278,832 exams were performed during study period. The age adjusted exam rate (all modalities) was significantly higher (p < 0.001) in non-Sami (females and males) group. There was no difference with regard to conventional radiography (CR) (p = 0.855). Whereas MR (p < 0.001) imaging was more common in the Sami group, CT (p < 0.001) and US (p = 0.003) exams were more frequently used in the control group. People living in Sami speaking communities experienced significantly less CT and US exams, but had more MR exams than the control group. A relatively high physical activity, obesity and a lower risk of cancer may be explanations.

Health consumption in Sami speaking municipalities and a control group with regard to medical imaging

PubMed Central

Størmer, Jan; Norum, Jan; Olsen, Lena Ringstad; Eldevik, Petter; Broderstad, Ann Ragnhild

2012-01-01

Objectives The Northern Norway Regional Health Authority trust aims to offer a high quality specialist health care to all inhabitants. The objective of this study was to document the consumption of medical imaging [conventional radiography (CR), computerised tomography (CT), magnetic resonance (MR), ultrasound (US)]. Methods The eight municipalities in northern Norway included in the administration area of the Sami language law (Sami group – 132,490 persons/year in the period 2003–2009, mean/year 19,363 inhabitants) were matched with a control group of 11 municipalities (non-Sami group – 135,539 persons/year, mean/year 18,927 inhabitants). Population data was accessed from Statistics Norway. Data on imaging exams were derived from a regional database including production data from all public and private institutions within the region. All four main modality groups (CR, CT, MR, US) were analysed. Variations for imaging frequency on each modality were compared between the Sami and non-Sami municipalities. Results A total of 278,832 exams were performed during study period. The age adjusted exam rate (all modalities) was significantly higher (p <0.001) in non-Sami (females and males) group. There was no difference with regard to conventional radiography (CR) (p=0.855). Whereas MR (p<0.001) imaging was more common in the Sami group, CT (p<0.001) and US (p=0.003) exams were more frequently used in the control group. Conclusion People living in Sami speaking communities experienced significantly less CT and US exams, but had more MR exams than the control group. A relatively high physical activity, obesity and a lower risk of cancer may be explanations. PMID:22456037

Evidence for Metabolic Hypothalamo-Amygdala Dysfunction in Narcolepsy

PubMed Central

Poryazova, Rositsa; Schnepf, Betina; Werth, Esther; Khatami, Ramin; Dydak, Ulrike; Meier, Dieter; Boesiger, Peter; Bassetti, Claudio L.

2009-01-01

Study Objectives: Proton resonance spectroscopy (1H-MRS) allows noninvasive chemical tissue analysis in the living brain. As neuronal loss and gliosis have been described in narcolepsy, metabolites of primary interest are N-acetylaspartate (NAA), a marker of neuronal integrity and myo-Inositol (mI), a glial marker and second messenger involved in the regulation of intracellular calcium. One 1H-MRS study in narcolepsy found no metabolic changes in the pontomedullary junction. Another study showed a reduction in NAA/creatine-phosphocreatine (Cr) in the hypothalamus of narcolepsy patients with cataplexy. We aimed to test for metabolic changes in specific brain areas, “regions of interest,” thought to be involved in emotional processing, sleep regulation and pathophysiology of narcolepsy: hypothalamus, pontomesencephalic junction and both amygdalae. Design: We performed 1H-MRS using a 3T Philips Achieva whole body MR scanner. Single-voxel proton MR spectra were acquired and quantified with LCModel to determine metabolite concentration ratios. Setting: The participants in the study were recruited at the outpatient clinic for sleep medicine, Department of Neurology and magnetic resonance spectroscopy was performed at the MRI facility, University Hospital Zurich. Participants: 1H-MRS was performed in fourteen narcolepsy patients with cataplexy, CSF hypocretin deficiency (10/10) and HLA-DQB1*0602 positivity (14/14) and 14 age, gender and body mass index matched controls. Patients were treatment naïve or off therapy for at least 14 days before scanning. Measurements and Results: No differences were observed in the regions of interest for (total NAA)/Cr ratios. Myo-Inositol (mI)/Cr was significantly lower in the right amygdala of the patients, compared to controls (P < 0.042). Significant negative correlations only in the patients group were found between (total NAA)/Cr in hypothalamus and mI/Cr in the right amygdala (r = −0.89, P < 0.001), between mI/Cr in hypothalamus and (total NAA)/Cr in the right amygdala (r = −63, P < 0.05) and between mI/Cr in the left amygdala and total NAA)/Cr in the pontomesencephalic junction (r = −0.69, P < 0.05). Conclusion: Our findings suggest amygdala involvement and possible hypothalamo-amygdala dysfunction in narcolepsy. Citation: Poryazova R; Werth E; Khatami R; Dydak U; Meier D; Boesiger P; Bassetti CL. Evidence for metabolic hypothalamo-amygdala dysfunction in narcolepsy. SLEEP 2009;32(5):607-613. PMID:19480227

Critical Behavior and Macroscopic Phase Diagram of the Monoaxial Chiral Helimagnet Cr 1/3NbS 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Clements, Eleanor M.; Das, Raja; Li, Ling

2017-07-26

Cr 1/3NbS 2 is a unique example of a hexagonal chiral helimagnet with high crystalline anisotropy, and has generated growing interest for a possible magnetic field control of the incommensurate spin spiral. Here, we construct a comprehensive phase diagram based on detailed magnetization measurements of a high quality single crystal of Cr 1/3NbS 2 over three magnetic field regions. An analysis of the critical properties in the forced ferromagnetic region yields 3D Heisenberg exponents β = 0.3460 ± 0.040, γ = 1.344 ± 0.002, and T C = 130.78 K ± 0.044, which are consistent with the localized nature themore » of Cr 3+ moments and suggest short-range ferromagnetic interactions. We exploit the temperature and magnetic field dependence of magnetic entropy change (ΔS M) to accurately map the nonlinear crossover to the chiral soliton lattice regime from the chiral helimagnetic phase. Our observations in the low field region are consistent with the existence of chiral ordering in a temperature range above the Curie temperature, T C < T < T*, where a first-order transition has been previously predicted. An analysis of the universal behavior of ΔS M(T,H) experimentally demonstrates for the first time the first-order nature of the onset of chiral ordering.« less

Distinct effects of Cr bulk doping and surface deposition on the chemical environment and electronic structure of the topological insulator Bi 2 Se 3

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yilmaz, Turgut; Hines, William; Sun, Fu-Chang

In this report, it is shown that Cr doped into the bulk and Cr deposited on the surface of Bi2Se3 films produced by molecular beam epitaxy (MBE) have strikingly different effects on both the electronic structure and chemical environment. Angle resolved photoemission spectroscopy (ARPES) shows that Cr doped into the bulk opens a surface state energy gap which can be seen at room temperature; much higher than the measured ferromagnetic transition temperature of ≈ 10 K. On the other hand, similar ARPES measurements show that the surface states remain gapless down to 15 K for films with Cr surface deposition.more » In addition, core-level photoemission spectroscopy of the Bi 5d, Se 3d, and Cr 3p core levels show distinct differences in the chemical environment for the two methods of Cr introduction. Surface deposition of Cr results in the formation of shoulders on the lower binding energy side for the Bi 5d peaks and two distinct Cr 3p peaks indicative of two Cr sites. These striking differences suggests an interesting possibility that better control of doping at only near surface region may offer a path to quantum anomalous Hall states at higher temperatures than reported in the literature.« less

Distinct effects of Cr bulk doping and surface deposition on the chemical environment and electronic structure of the topological insulator Bi 2 Se 3

DOE PAGES

Yilmaz, Turgut; Hines, William; Sun, Fu-Chang; ...

2017-02-21

In this report, it is shown that Cr doped into the bulk and Cr deposited on the surface of Bi2Se3 films produced by molecular beam epitaxy (MBE) have strikingly different effects on both the electronic structure and chemical environment. Angle resolved photoemission spectroscopy (ARPES) shows that Cr doped into the bulk opens a surface state energy gap which can be seen at room temperature; much higher than the measured ferromagnetic transition temperature of ≈ 10 K. On the other hand, similar ARPES measurements show that the surface states remain gapless down to 15 K for films with Cr surface deposition.more » In addition, core-level photoemission spectroscopy of the Bi 5d, Se 3d, and Cr 3p core levels show distinct differences in the chemical environment for the two methods of Cr introduction. Surface deposition of Cr results in the formation of shoulders on the lower binding energy side for the Bi 5d peaks and two distinct Cr 3p peaks indicative of two Cr sites. These striking differences suggests an interesting possibility that better control of doping at only near surface region may offer a path to quantum anomalous Hall states at higher temperatures than reported in the literature.« less

Concentration distribution and assessment of several heavy metals in sediments of west-four Pearl River Estuary

NASA Astrophysics Data System (ADS)

Wang, Shanshan; Cao, Zhimin; Lan, Dongzhao; Zheng, Zhichang; Li, Guihai

2008-09-01

Grain size parameters, trace metals (Co, Cu, Ni, Pb, Cr, Zn, Ba, Zr and Sr) and total organic matter (TOM) of 38 surficial sediments and a sediment core of west-four Pearl River Estuary region were analyzed. The spacial distribution and the transportation procession of the chemical element in surficial sediments were studied mainly. Multivariate statistics are used to analyses the interrelationship of metal elements, TOM and the grain size parameters. The results demonstrated that terrigenous sediment taken by the rivers are main sources of the trace metal elements and TOM, and the lithology of parent material is a dominating factor controlling the trace metal composition in the surficial sediment. In addition, the hydrodynamic condition and landform are the dominating factors controlling the large-scale distribution, while the anthropogenic input in the coastal area alters the regional distribution of heavy metal elements Co, Cu, Ni, Pb, Cr and Zn. The enrichment factor (EF) analysis was used for the differentiation of the metal source between anthropogenic and naturally occurring, and for the assessment of the anthropogenic influence, the deeper layer content of heavy metals were calculated as the background values and Zr was chosen as the reference element for Co, Cu, Ni, Pb, Cr and Zn. The result indicate prevalent enrichment of Co, Cu, Ni, Pb and Cr, and the contamination of Pb is most obvious, further more, the peculiar high EF value sites of Zn and Pb probably suggest point source input.

Diffusional creep and creep degradation in the dispersion-strengthened alloy TD-NiCr

NASA Technical Reports Server (NTRS)

Whittenberger, J. D.

1972-01-01

Dispersoid-free regions were observed in TD-NiCr (Ni-20Cr-2ThO2) after slow strain rate testing in air from 1145 to 1590 K. Formation of the dispersoid-free regions appears to be the result of diffusional creep. The net effect of this creep is the degradation of TD-NiCr to a duplex microstructure. Degradation is further enhanced by the formation of voids and integranular oxidation in the thoria-free regions. These regions apparently provided sites for void formation and oxide growth since the strength and oxidation resistance of Ni-20Cr is much less than Ni-20Cr-2ThO2. This localized oxidation does not appear to reduce the static load bearing capacity of TD-NiCr since long stress rupture lives were observed even with heavily oxidized microstructures. But this oxidation does significantly reduce the ductility and impact resistance of the material. Dispersoid-free bands and voids were also observed for two other dispersion strengthened alloys, TD-NiCrAl and IN-853. Thus, it appears that diffusional creep is charactertistic of dispersion-strengthened alloys and can play a major role in the creep degradation of these materials.

Corrosion-induced microstructural developments in 316 stainless steel during exposure to molten Li2BeF4(FLiBe) salt

NASA Astrophysics Data System (ADS)

Zheng, Guiqiu; He, Lingfeng; Carpenter, David; Sridharan, Kumar

2016-12-01

The microstructural developments in the near-surface regions of AISI 316 stainless steel during exposure to molten Li2BeF4 (FLiBe) salt have been investigated with the goal of using this material for the construction of the fluoride salt-cooled high-temperature reactor (FHR), a leading nuclear reactor concept for the next generation nuclear plants (NGNP). Tests were conducted in molten FLiBe salt (melting point: 459 °C) at 700 °C in graphite crucibles and 316 stainless steel crucibles for exposure duration of up to 3000 h. Corrosion-induced microstructural changes in the near-surface regions of the samples were characterized using scanning electron microscopy (SEM) in conjunction with energy dispersive x-ray spectroscopy (EDS) and electron backscatter diffraction (EBSD), and scanning transmission electron microscopy (STEM) with EDS capabilities. Intergranular corrosion attack in the near-surface regions was observed with associated Cr depletion along the grain boundaries. High-angle grain boundaries (15-180°) were particularly prone to intergranular attack and Cr depletion. The depth of attack extended to the depths of 22 μm after 3000-h exposure for the samples tested in graphite crucible, while similar exposure in 316 stainless steel crucible led to the attack depths of only about 11 μm. Testing in graphite crucibles led to the formation of nanometer-scale Mo2C, Cr7C3 and Al4C3 particle phases in the near-surface regions of the material. The copious depletion of Cr in the near-surface regions induced a γ-martensite to α-ferrite phase (FeNix) transformation. Based on the microstructural analysis, a thermal diffusion controlled corrosion model was developed and experimentally validated for predicting long-term corrosion attack depth.

ELEVATED GAMMA-AMINOBUTYRIC ACID LEVELS IN CHRONIC SCHIZOPHRENIA

PubMed Central

Öngür, Dost; Prescot, Andrew P.; McCarthy, Julie; Cohen, Bruce M.; Renshaw, Perry F.

2010-01-01

Background Despite widely-replicated abnormalities of gamma-aminobutyric acid (GABA) neurons in schizophrenia postmortem, few studies have measured tissue GABA levels in vivo. We used proton magnetic resonance spectroscopy to measure tissue GABA levels in participants with schizophrenia and healthy controls in the anterior cingulate cortex (ACC) and parieto-occipital cortex (POC). Methods 21 schizophrenia participants effectively treated on a stable medication regimen (mean age 39.0, 14 male) and 19 healthy controls (mean age 36.3, 12 male) underwent a proton magnetic resonance spectroscopy scan using GABA-selective editing at 4 Tesla after providing informed consent. Data were collected from two 16.7cc voxels and analyzed using LCModel. Results We found elevations in GABA/Cr in the schizophrenia group compared with controls (F(1,65)=4.149, p=0.046) in both brain areas (15.5% elevation in ACC, 11.9% in POC). We also found a positive correlation between GABA/Cr and Glu/Cr which was not accounted for by %GM or brain region. Conclusions We found elevated GABA/Cr in participants with chronically treated schizophrenia. Postmortem studies report evidence for dysfunctional GABAergic neurotransmission in schizophrenia. Elevated GABA levels, whether primary to illness or compensatory to another process, may be associated with dysfunctional GABAergic neurotransmission in chronic schizophrenia. PMID:20598290

Bacterial Cr(VI) reduction concurrently improves sunflower (Helianthus Annuus L.) growth.

PubMed

Faisal, Muhammad; Hasnain, Shahida

2005-07-01

Four Cr(VI)-reducing bacterial strains (Ochrobactrum intermedium, CrT-2, CrT-3 and CrT-4) previously isolated from chromium-contaminated sites were inoculated on to seeds of sunflower (Helianthus annuus var SF-187), which were germinated and grown along with non-inoculated controls with chromate salts (300 microg CrCl3 or K2CrO4 ml(-1)). Severe reduction (20%) in seed germination was observed in Cr(VI) stress. Plant height decreased (36%) with Cr(VI) when compared with chromium-free control, while O. intermedium inoculation resulted a 20% increment in this parameter as compared to non-inoculated chromium-free control. CrT-3 inoculation resulted a 69% increment in auxin content as compared to non-inoculated control. O. intermedium caused 30% decrease in chromium uptake in sunflower plant roots under Cr(VI) stress as compared to chromium-free control plants.

Availability and characteristics of cardiac rehabilitation programs in one Brazilian state: a cross-sectional study.

PubMed

Sérvio, Thaianne Cavalcante; Ghisi, Gabriela Lima de Melo; Silva, Lilian Pinto da; Silva, Luciana Duarte Novais; Lima, Marcia Maria Oliveira; Pereira, Danielle Aparecida Gomes; Grace, Sherry L; Britto, Raquel Rodrigues

2018-03-22

Cardiac rehabilitation (CR) is a recommended model of care for cardiovascular diseases; however, is not widely available and is underutilized, especially in low- and middle-income countries. To identify the CR programs available in one Brazilian state (Minas Gerais; MG) and describe their characteristics by funding type. In this multi-center descriptive study, CR programs were identified in four MG regions and 41 CR coordinators were sent a survey to report the characteristics of their programs, including CR components described in guidelines and barriers to patients' participation. Descriptive and comparative analysis between public and private programs were carried out. Forty-one CR programs were identified, only 21.9% public. Nineteen completed the survey. The majority of CR programs offered initial assessment and physical training. Components of comprehensive CR programs that were rarely offered included treatment of tobacco dependence, psychological support and lipid control. Physical therapists were present in all CR programs. The six-minute walk test was used in most programs to assess functional capacity. Programs were located intra-hospital only in public hospitals. Phase 2 (initial outpatient) and phase 4 (maintenance) were offered significantly more in private programs when compared to public ones. The main barrier for CR participation was the lack of referral. The availability of CR programs in MG state is low, especially public programs. Most programs do not offer all core components of CR. Copyright © 2018 Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia. Publicado por Elsevier Editora Ltda. All rights reserved.

Prefrontal N-acetylaspartate is strongly associated with memory performance in (abstinent) ecstasy users: preliminary report.

PubMed

Reneman, L; Majoie, C B; Schmand, B; van den Brink, W; den Heeten, G J

2001-10-01

3,4-methylenedioxymethamphetamine (MDMA or "Ecstasy") is known to damage brain serotonin neurons in animals and possibly humans. Because serotonergic damage may adversely affect memory, we compared verbal memory function between MDMA users and MDMA-naïve control subjects and evaluated the relationship between verbal memory function and neuronal dysfunction in the MDMA users. An auditory verbal memory task (Rey Auditory Verbal Learning Test) was used to study eight abstinent MDMA users and seven control subjects. In addition 1H-MRS was used in different brain regions of all MDMA users to measure N-acetylaspartate/creatine (NAA/Cr) ratios, a marker for neuronal viability. The MDMA users recalled significantly fewer words than control subjects on delayed (p =.03) but not immediate recall (p =.08). In MDMA users, delayed memory function was strongly associated with NAA/Cr only in the prefrontal cortex (R(2) =.76, p =.01). Greater decrements in memory function predicted lower NAA/Cr levels-and by inference greater neuronal dysfunction-in the prefrontal cortex of MDMA users.

Detection of human immunodeficiency virus induced inflammation and oxidative stress in lenticular nuclei with magnetic resonance spectroscopy despite antiretroviral therapy.

PubMed

Roc, Anne C; Ances, Beau M; Chawla, Sanjeev; Korczykowski, Marc; Wolf, Ronald L; Kolson, Dennis L; Detre, John A; Poptani, Harish

2007-09-01

Single-voxel magnetic resonance spectroscopy measurements of N-acetyl aspartate, choline, and creatine (Cr) are affected in patients with human immunodeficiency virus (HIV) and neurocognitive impairment. However, these metabolic markers are often normalized in affected central nervous system regions, such as the lenticular nuclei, after initiation of highly active antiretroviral therapy (HAART). To examine whether lactate (Lac), a marker of inflammation and anaerobic glycolysis, and lipid, an indicator of cell membrane turnover resulting from oxidative stress, could serve as surrogate biomarkers within the lenticular nuclei of HIV-positive patients with different degrees of neurocognitive impairment. Three-tesla 2-dimensional-chemical shift imaging magnetic resonance spectroscopy at echo times of 30 milliseconds and 135 milliseconds was performed in voxels overlapping the lenticular nuclei of seronegative controls and a spectrum of HIV-positive patients (neurocognitively normal, mildly impaired, or moderately to severely impaired). University of Pennsylvania, Philadelphia. Ten seronegative controls and 45 HIV-positive patients with different degrees of neurocognitive impairment (15 neurocognitively normal patients, 12 mildly impaired patients, and 18 moderately to severely impaired patients). In vivo 2-dimensional-chemical shift imaging magnetic resonance spectroscopy analysis of N-acetyl aspartate:Cr, choline:Cr, Lac:Cr, and (lipid + Lac):Cr ratios among the various groups. In addition, the effect of the degree of HAART central nervous system penetration (high vs low) on these ratios was studied. No significant lenticular nuclei atrophy was detected with volumes similar across all of the groups. Both N-acetyl aspartate:Cr and choline:Cr ratios were similar across all of the groups at either echo time. In contrast, the Lac:Cr ratio was significantly greater in HIV-positive patients with moderate to severe impairment compared with seronegative controls. The (lipid + Lac):Cr ratio was significantly elevated within each HIV-positive subgroup compared with seronegative controls. Within HIV-positive patients receiving HAART, the degree of central nervous system penetration (high vs low) did not affect metabolic ratios. As seen with 2-dimensional-chemical shift imaging magnetic resonance spectroscopy, HIV induces inflammation and oxidative stress in HIV-positive patients despite HAART. Lipid and Lac are more sensitive inflammatory biomarkers that may be used to differentiate HIV-positive subgroups. However, no significant difference in efficacy, as measured by metabolic ratios, exists for high- vs low-central nervous system-penetrating HAART.

Postictal in situ MRS brain lactate in the rat kindling model.

PubMed

Maton, B M; Najm, I M; Wang, Y; Lüders, H O; Ng, T C

1999-12-10

To determine the temporal and spatial extent of the lactate (Lact) changes as correlated with seizure characteristics and EEG changes in the rat kindling model. Prior studies using MRS have detected cerebral Lact postictally in animal models of seizures and in patients with intractable focal epilepsy. We performed MRS in sham control rats (n = 4) and in rats stimulated in the right hippocampus at two different stages of the kindling and at three time points after the seizures: <2 hours (n = 8 and 5, stage 0 and stage 5), 2 to 3 hours (n = 5 and 6), and >3 hours (n = 4 and 2). Lact/creatine (Cr) and N-acetylaspartate (NAA)/Cr ratios were measured in six contiguous voxels (three left, three right) covering the hippocampi, anterior and posterior regions, and compared with EEG and ictal behavior. Lact/Cr ratios were measured at a very low level in the sham control rats and in the >3-hour group. In the <2-hour group, Lact/Cr increase was higher in stage-5 rats as compared with stage-0 rats (p = 0.001, unpaired t-test) and sham control rats when all the voxels were considered. Lact/Cr ratios were higher in the stimulated area as compared with all other brain areas in stage-0 rats (p = 0.05, paired t-test) but not in the stage-5 rats. Similar results with more inter-animal variability were measured in the 2- to 3-hour group. NAA/Cr ratios increased significantly after stage-0 kindling in the stimulated hippocampus but not after stage-5 kindling. Postictal Lact increase as assayed by MRS correlates with EEG and behavioral seizures and suggests that it would be an additional noninvasive technique for seizure localization during the presurgical evaluation of patients with intractable focal epilepsy.

Reversing pathologically increased EEG power by acoustic coordinated reset neuromodulation

PubMed Central

Adamchic, Ilya; Toth, Timea; Hauptmann, Christian; Tass, Peter Alexander

2014-01-01

Acoustic Coordinated Reset (CR) neuromodulation is a patterned stimulation with tones adjusted to the patient's dominant tinnitus frequency, which aims at desynchronizing pathological neuronal synchronization. In a recent proof-of-concept study, CR therapy, delivered 4–6 h/day more than 12 weeks, induced a significant clinical improvement along with a significant long-lasting decrease of pathological oscillatory power in the low frequency as well as γ band and an increase of the α power in a network of tinnitus-related brain areas. As yet, it remains unclear whether CR shifts the brain activity toward physiological levels or whether it induces clinically beneficial, but nonetheless abnormal electroencephalographic (EEG) patterns, for example excessively decreased δ and/or γ. Here, we compared the patients' spontaneous EEG data at baseline as well as after 12 weeks of CR therapy with the spontaneous EEG of healthy controls by means of Brain Electrical Source Analysis source montage and standardized low-resolution brain electromagnetic tomography techniques. The relationship between changes in EEG power and clinical scores was investigated using a partial least squares approach. In this way, we show that acoustic CR neuromodulation leads to a normalization of the oscillatory power in the tinnitus-related network of brain areas, most prominently in temporal regions. A positive association was found between the changes in tinnitus severity and the normalization of δ and γ power in the temporal, parietal, and cingulate cortical regions. Our findings demonstrate a widespread CR-induced normalization of EEG power, significantly associated with a reduction of tinnitus severity. PMID:23907785

Expression of Cry1Ac toxin-binding region in Plutella xyllostella cadherin-like receptor and studying their interaction mode by molecular docking and site-directed mutagenesis.

PubMed

Hu, Xiaodan; Zhang, Xiao; Zhong, Jianfeng; Liu, Yuan; Zhang, Cunzheng; Xie, Yajing; Lin, Manman; Xu, Chongxin; Lu, Lina; Zhu, Qing; Liu, Xianjin

2018-05-01

Cadherin-like protein has been identified as the primary Bacillus thuringiensis (Bt) Cry toxin receptor in Lepidoptera pests and plays a key role in Cry toxin insecticidal. In this study, we successfully expressed the putative Cry1Ac toxin-binding region (CR7-CR11) of Plutella xylostella cadherin-like in Escherichia coli BL21 (DE3). The expressed CR7-CR11 fragment showed binding ability to Cry1Ac toxin under denaturing (Ligand blot) and non-denaturing (ELISA) conditions. The three-dimensional structure of CR7-CR11 was constructed by homology modeling. Molecular docking results of CR7-CR11 and Cry1Ac showed that domain II and domain III of Cry1Ac were taking part in binding to CR7-CR11, while CR7-CR8 was the region of CR7-CR11 in interacting with Cry1Ac. The interaction of toxin-receptor complex was found to arise from hydrogen bond and hydrophobic interaction. Through the computer-aided alanine mutation scanning, amino acid residues of Cry1Ac (Met341, Asn442 and Ser486) and CR7-CR11 (Asp32, Arg101 and Arg127) were predicted as the hot spot residues involved in the interaction of the toxin-receptor complex. At last, we verified the importance role of these key amino acid residues by binding assay. These results will lay a foundation for further elucidating the insecticidal mechanism of Cry toxin and enhancing Cry toxin insecticidal activity by molecular modification. Copyright © 2018 Elsevier B.V. All rights reserved.

Effect of laser absorption on picosecond laser ablation of Cr12MoV mold steel, 9Cr18 stainless steel and H13A cemented carbide

NASA Astrophysics Data System (ADS)

Wu, Baoye; Liu, Peng; Wang, Xizhao; Zhang, Fei; Deng, Leimin; Duan, Jun; Zeng, Xiaoyan

2018-05-01

Due to excellent properties, Cr12MoV mold steel, 9Cr18 stainless steel and H13A cemented carbide are widely used in industry. In this paper, the effect of absorption of laser light on ablation efficiency and roughness have been studied using a picosecond pulse Nd:YVO4 laser. The experimental results reveal that laser wavelength, original surface roughness and chemical composition play an important role in controlling ablation efficiency and roughness. Firstly, higher ablation efficiency with lower surface roughness is achieved on the ablation of 9Cr18 at 532, comparing with 1064 nm. Secondly, the ablation efficiency increases while the Ra of the ablated region decreases with the decrease of original surface roughness on ablation of Cr12MoV mold steel at 532 nm. Thirdly, the ablation efficiency of H13A cemented carbide is much higher than 9Cr18 stainless steel and Cr12MoV mold steel at 1064 nm. Scanning electron microscopy images reveals the formation of pores on the surface of 9Cr18 stainless steel and Cr12MoV mold steel at 532 nm while no pores are formed at 1064 nm. As to H13A cemented carbide, worm-like structure is formed at 1064 nm. The synergetic effects of the heat accumulation, plasma shielding and ablation threshold on laser ablation efficiency and machining quality were analyzed and discussed systematically in this paper.

Alzheimer disease alters the relationship of cardiorespiratory fitness with brain activity during the stroop task.

PubMed

Vidoni, Eric D; Gayed, Matthew R; Honea, Robyn A; Savage, Cary R; Hobbs, Derek; Burns, Jeffrey M

2013-07-01

Despite mounting evidence that physical activity has positive benefits for brain and cognitive health, there has been little characterization of the relationship between cardiorespiratory (CR) fitness and cognition-associated brain activity as measured by functional magnetic resonance imaging (fMRI). The lack of evidence is particularly glaring for diseases such as Alzheimer disease (AD) that degrade cognitive and functional performance. The aim of this study was to describe the relationship between regional brain activity during cognitive tasks and CR fitness level in people with and without AD. A case-control, single-observation study design was used. Thirty-four individuals (18 without dementia and 16 in the earliest stages of AD) completed maximal exercise testing and performed a Stroop task during fMRI. Cardiorespiratory fitness was inversely associated with anterior cingulate activity in the participants without dementia (r=-.48, P=.05) and unassociated with activation in those with AD (P>.7). Weak associations of CR fitness and middle frontal cortex were noted. The wide age range and the use of a single task in fMRI rather than multiple tasks challenging different cognitive capacities were limitations of the study. The results offer further support of the relationship between CR fitness and regional brain activity. However, this relationship may be attenuated by disease. Future work in this area may provide clinicians and researchers with interpretable and dependable regional fMRI biomarker signatures responsive to exercise intervention. It also may shed light on mechanisms by which exercise can support cognitive function.

Genetic diversity of the captive Asian tapir population in Thailand, based on mitochondrial control region sequence data and the comparison of its nucleotide structure with Brazilian tapir.

PubMed

Muangkram, Yuttamol; Amano, Akira; Wajjwalku, Worawidh; Pinyopummintr, Tanu; Thongtip, Nikorn; Kaolim, Nongnid; Sukmak, Manakorn; Kamolnorranath, Sumate; Siriaroonrat, Boripat; Tipkantha, Wanlaya; Maikaew, Umaporn; Thomas, Warisara; Polsrila, Kanda; Dongsaard, Kwanreaun; Sanannu, Saowaphang; Wattananorrasate, Anuwat

2017-07-01

The Asian tapir (Tapirus indicus) has been classified as Endangered on the IUCN Red List of Threatened Species (2008). Genetic diversity data provide important information for the management of captive breeding and conservation of this species. We analyzed mitochondrial control region (CR) sequences from 37 captive Asian tapirs in Thailand. Multiple alignments of the full-length CR sequences sized 1268 bp comprised three domains as described in other mammal species. Analysis of 16 parsimony-informative variable sites revealed 11 haplotypes. Furthermore, the phylogenetic analysis using median-joining network clearly showed three clades correlated with our earlier cytochrome b gene study in this endangered species. The repetitive motif is located between first and second conserved sequence blocks, similar to the Brazilian tapir. The highest polymorphic site was located in the extended termination associated sequences domain. The results could be applied for future genetic management based in captivity and wild that shows stable populations.

Phase Transformation and Aging Behavior of Al0.5CoCrFeNiSi0.2 High-Entropy Alloy

NASA Astrophysics Data System (ADS)

Zhang, C.; Wu, G. F.; Dai, P. Q.

2015-05-01

An Al0.5CoCrFeNiSi0.2 high-entropy alloy was prepared by vacuum arc melting. The alloy was aged from 700 to 1100 °C. The effects of aging on the phase transformation and mechanical performances were explored. The as-cast alloy showed a dendritic (DR) microstructure. The DR region was an Fe,Cr-rich FCC phase, while the interdendritic (ID) region was a spinodal structure composed of Fe,Cr-rich BCC (A2) and Ni,Al-rich BCC (B2) phases. At aging temperatures between 700 and 900 °C, the Fe,Cr-rich BCC (A2) phase in the ID region transformed into σ and Fe,Cr-rich FCC phases. Meanwhile, some Ni,Al-rich FCC phase particles precipitated from the DR region. During aging at 1100 °C, the DR microstructure disappeared, and a microstructure composed of Fe,Cr-rich FCC and Ni,Al-rich BCC (B2) phases both possessing a lamellar shape was developed. The alloy exhibited evident hardening and lower tensile strain when the aging temperature was lower than 1000 °C, which was mainly attributed to the generation of the σ phase in the ID region. However, a contrasting behavior was observed when the aging temperature was higher than 1000 °C, which was attributed to the redissolution of the σ phase and the microstructure coarsening.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rushton, Phillip S.; Olek, Anna T.; Makowski, Lee

The crystallographic structure of a rice (Oryza sativa) cellulose synthase, OsCesA8, plant-conserved region (P-CR), one of two unique domains in the catalytic domain of plant CesAs, was solved to 2.4 Å resolution. Two antiparallel α-helices form a coiled-coil domain linked by a large extended connector loop containing a conserved trio of aromatic residues. The P-CR structure was fit into a molecular envelope for the P-CR domain derived from small-angle X-ray scattering data. The P-CR structure and molecular envelope, combined with a homology-based chain trace of the CesA8 catalytic core, were modeled into a previously determined CesA8 small-angle X-ray scattering molecularmore » envelope to produce a detailed topological model of the CesA8 catalytic domain. The predicted position for the P-CR domain from the molecular docking models places the P-CR connector loop into a hydrophobic pocket of the catalytic core, with the coiled-coil aligned near the entrance of the substrate UDP-glucose into the active site. In this configuration, the P-CR coiled-coil alone is unlikely to regulate substrate access to the active site, but it could interact with other domains of CesA, accessory proteins, or other CesA catalytic domains to control substrate delivery.« less

Increased N-Acetylaspartate/creatine ratio in the medial prefrontal cortex among unmedicated obsessive-compulsive disorder patients.

PubMed

Fan, Qing; Tan, Ling; You, Chao; Wang, Jijun; Ross, Colin A; Wang, Xuemei; Zhang, Tianhong; Li, Jianqi; Chen, Kemin; Xiao, Zeping

2010-10-01

Changes in the fronto-striato-thalamo-cortical-circuit loop have been suggested in the pathogenesis of obsessive-compulsive disorder (OCD), and have been studied using (1)H magnetic resonance spectroscopy ((1)H MRS) with interesting findings. However, whether neural metabolites are abnormal in the medial prefrontal cortex in patients with OCD is unknown. The purpose of the present study was to investigate neural metabolites in this brain region in a sample of patients with OCD. Subjects were 21 unmedicated OCD patients, including 10 who were drug-naïve, and 19 healthy controls. Single-voxel (1)H MRS was used to study the medial prefrontal cortex for each subject. Levels of N-acetylaspartate (NAA), choline-containing compounds and myoinositol were measured in terms of their ratios with creatine (Cr). The NAA/Cr ratio was significantly higher among OCD patients than among healthy controls (F = 4.76, P = 0.037). However, it did not correlate with patients' symptoms or with their illness durations. The NAA/Cr ratio also did not differ between drug-naïve and previously medicated patients. No significant group differences were found between OCD patients and normal controls for the choline-containing compounds/Cr or myoinositol/Cr ratios. In addition, a significant correlation between the NAA/Cr ratio and trait anxiety scores on the State-Trait Anxiety Inventory was found among the controls (r = 0.639, P = 0.010). The N-Acetylaspartate level relative to creatine in the medial prefrontal cortex was increased among unmedicated OCD patients. This cannot be attributed to the effect of medications. The possible significance of this finding in the pathophysiology of OCD is discussed. © 2010 Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine. Psychiatry and Clinical Neurosciences © 2010 Japanese Society of Psychiatry and Neurology.

The distribution and dynamics of chromium and nickel in cultivated and uncultivated semi-arid soils from Nigeria.

PubMed

Agbenin, John O

2002-12-02

Growing concern about heavy metal contamination of agricultural lands under long-term application of inorganic fertilizers and organic wastes makes periodic risk assessment of heavy metal accumulation in arable lands imperative. As a part of a much larger study to systematically document the status of heavy metals in savanna soils this study investigated the distribution and dynamics of Cr and Ni in a savanna soil after 50 years of continuous cultivation and application of inorganic fertilizers and organic manures. The cultivated fields were fertilized with inorganic fertilizers (NPK), farmyard manure (FYM), FYM+NPK for 50 years and a control plot under continuous cultivation for 50 years but did not receive either FYM or NPK. Two uncultivated or natural sites were sampled as reference conditions for assessing the dynamics of Cr and Ni induced by cultivation and management practices. The distribution of Cr and Ni in the soil profiles exhibited eluvial-illuvial patterns. Sand and clay fractions explained between 62 and 90% of the variance in Cr and Ni concentration and distribution in the soil profiles. Mean Cr concentrations ranged from 17 to 59 mg kg(-1), while Ni varied from <1 mg kg(-1) in the topsoil to 16 mg kg(-1) in the subsoil. Mass balance calculations showed a loss of 10% Cr and 17% Ni in the FYM field, and approximately 4% Cr and 11% Ni in the NPK field compared to the natural site after 50 years of cultivation. The control and FYM + NPK field had, however, a positive balance of Cr and Ni. In general, it was concluded that existing soil management practices in this region are unlikely to lead to Cr and Ni build-up probably because of low rates of application of inorganic fertilizers, farmyard manure and other organic wastes to the soils.

Identification of a transient Sox5 expressing progenitor population in the neonatal ventral forebrain by a novel cis-regulatory element

PubMed Central

Hao, Hailing; Li, Ying; Tzatzalos, Evangeline; Gilbert, Jordana; Zala, Dhara; Bhaumik, Mantu; Cai, Li

2014-01-01

Precise control of lineage-specific gene expression in the neural stem/progenitor cells is crucial for generation of the diversity of neuronal and glial cell types in the central nervous system (CNS). The mechanism underlying such gene regulation, however, is not fully elucidated. Here, we report that a 377 bp evolutionarily conserved DNA fragment (CR5), located approximately 32 kbp upstream of Olig2 transcription start site, acts as a cis-regulator for gene expression in the development of the neonatal forebrain. CR5 is active in a time-specific and brain region-restricted manner. CR5 activity is not detected in the embryonic stage, but it is exclusively in a subset of Sox5+ cells in the neonatal ventral forebrain. Furthermore, we show that Sox5 binding motif in CR5 is important for this cell-specific gene regulatory activity; mutation of Sox5 binding motif in CR5 alters reporter gene expression with different cellular composition. Together, our study provides new insights into the regulation of cell-specific gene expression during CNS development. PMID:24954155

Magnesium and 54Cr isotope compositions of carbonaceous chondrite chondrules – Insights into early disk processes

PubMed Central

Olsen, Mia B.; Wielandt, Daniel; Schiller, Martin; Van Kooten, Elishevah M.M.E.; Bizzarro, Martin

2016-01-01

We report on the petrology, magnesium isotopes and mass-independent 54Cr/52Cr compositions (μ54Cr) of 42 chondrules from CV (Vigarano and NWA 3118) and CR (NWA 6043, NWA 801 and LAP 02342) chondrites. All sampled chondrules are classified as type IA or type IAB, have low 27Al/24Mg ratios (0.04–0.27) and display little or no evidence for secondary alteration processes. The CV and CR chondrules show variable 25Mg/24Mg and 26Mg/24Mg values corresponding to a range of mass-dependent fractionation of ~500 ppm (parts per million) per atomic mass unit. This mass-dependent Mg isotope fractionation is interpreted as reflecting Mg isotope heterogeneity of the chondrule precursors and not the result of secondary alteration or volatility-controlled processes during chondrule formation. The CV and CR chondrule populations studied here are characterized by systematic deficits in the mass-independent component of 26Mg (μ26Mg*) relative to the solar value defined by CI chondrites, which we interpret as reflecting formation from precursor material with a reduced initial abundance of 26Al compared to the canonical 26Al/27Al of ~5 × 10−5. Model initial 26Al/27Al values of CV and CR chondrules vary from (1.5 ± 4.0) × 10−6 to (2.2 ± 0.4) × 10−5. The CV chondrules display significant μ54Cr variability, defining a range of compositions that is comparable to that observed for inner Solar System primitive and differentiated meteorites. In contrast, CR chondrites are characterized by a narrower range of μ54Cr values restricted to compositions typically observed for bulk carbonaceous chondrites. Collectively, these observations suggest that the CV chondrules formed from precursors that originated in various regions of the protoplanetary disk and were then transported to the accretion region of the CV parent asteroid whereas CR chondrule predominantly formed from precursor with carbonaceous chondrite-like μ54Cr signatures. The observed μ54Cr variability in chondrules from CV and CR chondrites suggest that the matrix and chondrules did not necessarily formed from the same reservoir. The coupled μ26Mg* and μ54Cr systematics of CR chondrules establishes that these objects formed from a thermally unprocessed and 26Al-poor source reservoir distinct from most inner Solar System asteroids and planetary bodies, possibly located beyond the orbits of the gas giants. In contrast, a large fraction of the CV chondrules plot on the inner Solar System correlation line, indicating that these objects predominantly formed from thermally-processed, 26Al-bearing precursor material akin to that of inner Solar System solids, asteroids and planets. PMID:27563152

Magnesium and 54Cr isotope compositions of carbonaceous chondrite chondrules - Insights into early disk processes

NASA Astrophysics Data System (ADS)

Olsen, Mia B.; Wielandt, Daniel; Schiller, Martin; Van Kooten, Elishevah M. M. E.; Bizzarro, Martin

2016-10-01

We report on the petrology, magnesium isotopes and mass-independent 54Cr/52Cr compositions (μ54Cr) of 42 chondrules from CV (Vigarano and NWA 3118) and CR (NWA 6043, NWA 801 and LAP 02342) chondrites. All sampled chondrules are classified as type IA or type IAB, have low 27Al/24Mg ratios (0.04-0.27) and display little or no evidence for secondary alteration processes. The CV and CR chondrules show variable 25Mg/24Mg and 26Mg/24Mg values corresponding to a range of mass-dependent fractionation of ∼500 ppm (parts per million) per atomic mass unit. This mass-dependent Mg isotope fractionation is interpreted as reflecting Mg isotope heterogeneity of the chondrule precursors and not the result of secondary alteration or volatility-controlled processes during chondrule formation. The CV and CR chondrule populations studied here are characterized by systematic deficits in the mass-independent component of 26Mg (μ26Mg∗) relative to the solar value defined by CI chondrites, which we interpret as reflecting formation from precursor material with a reduced initial abundance of 26Al compared to the canonical 26Al/27Al of ∼5 × 10-5. Model initial 26Al/27Al values of CV and CR chondrules vary from (1.5 ± 4.0) × 10-6 to (2.2 ± 0.4) × 10-5. The CV chondrules display significant μ54Cr variability, defining a range of compositions that is comparable to that observed for inner Solar System primitive and differentiated meteorites. In contrast, CR chondrites are characterized by a narrower range of μ54Cr values restricted to compositions typically observed for bulk carbonaceous chondrites. Collectively, these observations suggest that the CV chondrules formed from precursors that originated in various regions of the protoplanetary disk and were then transported to the accretion region of the CV parent asteroid whereas CR chondrule predominantly formed from precursor with carbonaceous chondrite-like μ54Cr signatures. The observed μ54Cr variability in chondrules from CV and CR chondrites suggest that the matrix and chondrules did not necessarily formed from the same reservoir. The coupled μ26Mg∗ and μ54Cr systematics of CR chondrules establishes that these objects formed from a thermally unprocessed and 26Al-poor source reservoir distinct from most inner Solar System asteroids and planetary bodies, possibly located beyond the orbits of the gas giants. In contrast, a large fraction of the CV chondrules plot on the inner Solar System correlation line, indicating that these objects predominantly formed from thermally-processed, 26Al-bearing precursor material akin to that of inner Solar System solids, asteroids and planets.

Synchrotron-based imaging of chromium and  γ-H2AX immunostaining in the duodenum following repeated exposure to Cr(VI) in drinking water

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thompson, Chad M.; Seiter, Jennifer; Chappell, Mark A.

Current drinking water standards for chromium are for the combined total of both hexavalent and trivalent chromium (Cr(VI) and Cr(III)). However, recent studies have shown that Cr(III) is not carcinogenic to rodents, whereas mice chronically exposed to high levels of Cr(VI) developed duodenal tumors. These findings may suggest the need for environmental standards specific for Cr(VI). Whether the intestinal tumors arose through a mutagenic or non-mutagenic mode of action (MOA) greatly impacts how drinking water standards for Cr(VI) are derived. Herein, X-ray fluorescence (spectro)microscopy (µ-XRF) was used to image the Cr content in the villus and crypt regions of duodenamore » from B6C3F1 mice exposed to 180 mg/l Cr(VI) in drinking water for 13 weeks. DNA damage was also assessed by γ-H2AX immunostaining. Exposure to Cr(VI) induced villus blunting and crypt hyperplasia in the duodenum—the latter evidenced by lengthening of the crypt compartment by ~2-fold with a concomitant 1.5-fold increase in the number of crypt enterocytes. γ-H2AX immunostaining was elevated in villi, but not in the crypt compartment. µ-XRF maps revealed mean Cr levels >30 times higher in duodenal villi than crypt regions; mean Cr levels in crypt regions were only slightly above background signal. Despite the presence of Cr and elevated γ-H2AX immunoreactivity in villi, no aberrant foci indicative of transformation were evident. Lastly, these findings do not support a MOA for intestinal carcinogenesis involving direct Cr-DNA interaction in intestinal stem cells, but rather support a non-mutagenic MOA involving chronic wounding of intestinal villi and crypt cell hyperplasia.« less

Synchrotron-Based Imaging of Chromium and γ-H2AX Immunostaining in the Duodenum Following Repeated Exposure to Cr(VI) in Drinking Water

PubMed Central

Thompson, Chad M.; Seiter, Jennifer; Chappell, Mark A.; Tappero, Ryan V.; Proctor, Deborah M.; Suh, Mina; Wolf, Jeffrey C.; Haws, Laurie C.; Vitale, Rock; Mittal, Liz; Kirman, Christopher R.; Hays, Sean M.; Harris, Mark A.

2015-01-01

Current drinking water standards for chromium are for the combined total of both hexavalent and trivalent chromium (Cr(VI) and Cr(III)). However, recent studies have shown that Cr(III) is not carcinogenic to rodents, whereas mice chronically exposed to high levels of Cr(VI) developed duodenal tumors. These findings may suggest the need for environmental standards specific for Cr(VI). Whether the intestinal tumors arose through a mutagenic or non-mutagenic mode of action (MOA) greatly impacts how drinking water standards for Cr(VI) are derived. Herein, X-ray fluorescence (spectro)microscopy (µ-XRF) was used to image the Cr content in the villus and crypt regions of duodena from B6C3F1 mice exposed to 180 mg/l Cr(VI) in drinking water for 13 weeks. DNA damage was also assessed by γ-H2AX immunostaining. Exposure to Cr(VI) induced villus blunting and crypt hyperplasia in the duodenum—the latter evidenced by lengthening of the crypt compartment by ∼2-fold with a concomitant 1.5-fold increase in the number of crypt enterocytes. γ-H2AX immunostaining was elevated in villi, but not in the crypt compartment. µ-XRF maps revealed mean Cr levels >30 times higher in duodenal villi than crypt regions; mean Cr levels in crypt regions were only slightly above background signal. Despite the presence of Cr and elevated γ-H2AX immunoreactivity in villi, no aberrant foci indicative of transformation were evident. These findings do not support a MOA for intestinal carcinogenesis involving direct Cr-DNA interaction in intestinal stem cells, but rather support a non-mutagenic MOA involving chronic wounding of intestinal villi and crypt cell hyperplasia. PMID:25352572

Synchrotron-based imaging of chromium and  γ-H2AX immunostaining in the duodenum following repeated exposure to Cr(VI) in drinking water

DOE PAGES

Thompson, Chad M.; Seiter, Jennifer; Chappell, Mark A.; ...

2014-10-28

Current drinking water standards for chromium are for the combined total of both hexavalent and trivalent chromium (Cr(VI) and Cr(III)). However, recent studies have shown that Cr(III) is not carcinogenic to rodents, whereas mice chronically exposed to high levels of Cr(VI) developed duodenal tumors. These findings may suggest the need for environmental standards specific for Cr(VI). Whether the intestinal tumors arose through a mutagenic or non-mutagenic mode of action (MOA) greatly impacts how drinking water standards for Cr(VI) are derived. Herein, X-ray fluorescence (spectro)microscopy (µ-XRF) was used to image the Cr content in the villus and crypt regions of duodenamore » from B6C3F1 mice exposed to 180 mg/l Cr(VI) in drinking water for 13 weeks. DNA damage was also assessed by γ-H2AX immunostaining. Exposure to Cr(VI) induced villus blunting and crypt hyperplasia in the duodenum—the latter evidenced by lengthening of the crypt compartment by ~2-fold with a concomitant 1.5-fold increase in the number of crypt enterocytes. γ-H2AX immunostaining was elevated in villi, but not in the crypt compartment. µ-XRF maps revealed mean Cr levels >30 times higher in duodenal villi than crypt regions; mean Cr levels in crypt regions were only slightly above background signal. Despite the presence of Cr and elevated γ-H2AX immunoreactivity in villi, no aberrant foci indicative of transformation were evident. Lastly, these findings do not support a MOA for intestinal carcinogenesis involving direct Cr-DNA interaction in intestinal stem cells, but rather support a non-mutagenic MOA involving chronic wounding of intestinal villi and crypt cell hyperplasia.« less

Body-composition changes in the Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy (CALERIE)-2 study: a 2-y randomized controlled trial of calorie restriction in nonobese humans.

PubMed

Das, Sai Krupa; Roberts, Susan B; Bhapkar, Manjushri V; Villareal, Dennis T; Fontana, Luigi; Martin, Corby K; Racette, Susan B; Fuss, Paul J; Kraus, William E; Wong, William W; Saltzman, Edward; Pieper, Carl F; Fielding, Roger A; Schwartz, Ann V; Ravussin, Eric; Redman, Leanne M

2017-04-01

Background: Calorie restriction (CR) retards aging and increases longevity in many animal models. However, it is unclear whether CR can be implemented in humans without adverse effects on body composition. Objective: We evaluated the effect of a 2-y CR regimen on body composition including the influence of sex and body mass index (BMI; in kg/m 2 ) among participants enrolled in CALERIE-2 (Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy), a multicenter, randomized controlled trial. Design: Participants were 218 nonobese (BMI: 21.9-28.0) adults aged 21-51 y who were randomly assigned to 25% CR (CR, n = 143) or ad libitum control (AL, n = 75) in a 2:1 ratio. Measures at baseline and 12 and 24 mo included body weight, waist circumference, fat mass (FM), fat-free mass (FFM), and appendicular mass by dual-energy X-ray absorptiometry; activity-related energy expenditure (AREE) by doubly labeled water; and dietary protein intake by self-report. Values are expressed as means ± SDs. Results: The CR group achieved 11.9% ± 0.7% CR over 2-y and had significant decreases in weight (-7.6 ± 0.3 compared with 0.4 ± 0.5 kg), waist circumference (-6.2 ± 0.4 compared with 0.9 ± 0.5 cm), FM (-5.4 ± 0.3 compared with 0.5 ± 0.4 kg), and FFM (-2.0 ± 0.2 compared with -0.0 ± 0.2 kg) at 24 mo relative to the AL group (all between-group P < 0.001). Moreover, FFM as a percentage of body weight at 24 mo was higher, and percentage of FM was lower in the CR group than in the AL. AREE, but not protein intake, predicted preservation of FFM during CR ( P < 0.01). Men in the CR group lost significantly more trunk fat ( P = 0.03) and FFM expressed as a percentage of weight loss ( P < 0.001) than women in the CR group. Conclusions: Two years of CR had broadly favorable effects on both whole-body and regional adiposity that could facilitate health span in humans. The decrements in FFM were commensurate with the reduced body mass; although men in the CR group lost more FFM than the women did, the percentage of FFM in the men in the CR group was higher than at baseline. CALERIE was registered at clinicaltrials.gov as NCT00427193. © 2017 American Society for Nutrition.

Body-composition changes in the Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy (CALERIE)-2 study: a 2-y randomized controlled trial of calorie restriction in nonobese humans123

PubMed Central

Roberts, Susan B

2017-01-01

Background: Calorie restriction (CR) retards aging and increases longevity in many animal models. However, it is unclear whether CR can be implemented in humans without adverse effects on body composition. Objective: We evaluated the effect of a 2-y CR regimen on body composition including the influence of sex and body mass index (BMI; in kg/m2) among participants enrolled in CALERIE-2 (Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy), a multicenter, randomized controlled trial. Design: Participants were 218 nonobese (BMI: 21.9–28.0) adults aged 21–51 y who were randomly assigned to 25% CR (CR, n = 143) or ad libitum control (AL, n = 75) in a 2:1 ratio. Measures at baseline and 12 and 24 mo included body weight, waist circumference, fat mass (FM), fat-free mass (FFM), and appendicular mass by dual-energy X-ray absorptiometry; activity-related energy expenditure (AREE) by doubly labeled water; and dietary protein intake by self-report. Values are expressed as means ± SDs. Results: The CR group achieved 11.9% ± 0.7% CR over 2-y and had significant decreases in weight (−7.6 ± 0.3 compared with 0.4 ± 0.5 kg), waist circumference (−6.2 ± 0.4 compared with 0.9 ± 0.5 cm), FM (−5.4 ± 0.3 compared with 0.5 ± 0.4 kg), and FFM (−2.0 ± 0.2 compared with −0.0 ± 0.2 kg) at 24 mo relative to the AL group (all between-group P < 0.001). Moreover, FFM as a percentage of body weight at 24 mo was higher, and percentage of FM was lower in the CR group than in the AL. AREE, but not protein intake, predicted preservation of FFM during CR (P < 0.01). Men in the CR group lost significantly more trunk fat (P = 0.03) and FFM expressed as a percentage of weight loss (P < 0.001) than women in the CR group. Conclusions: Two years of CR had broadly favorable effects on both whole-body and regional adiposity that could facilitate health span in humans. The decrements in FFM were commensurate with the reduced body mass; although men in the CR group lost more FFM than the women did, the percentage of FFM in the men in the CR group was higher than at baseline. CALERIE was registered at clinicaltrials.gov as NCT00427193. PMID:28228420

Assessing the pollution risk of soil Chromium based on loading capacity of paddy soil at a regional scale

PubMed Central

Qu, Mingkai; Li, Weidong; Zhang, Chuanrong; Huang, Biao; Zhao, Yongcun

2015-01-01

The accumulation of a trace metal in rice grain is not only affected by the total concentration of the soil trace metal, but also by crop variety and related soil properties, such as soil pH, soil organic matter (SOM) and so on. However, these factors were seldom considered in previous studies on mapping the pollution risk of trace metals in paddy soil at a regional scale. In this study, the spatial nonstationary relationships between rice-Cr and a set of perceived soil properties (soil-Cr, soil pH and SOM) were explored using geographically weighted regression; and the relationships were then used for calculating the critical threshold (CT) of soil-Cr concentration that may ensure the concentration of rice-Cr being below the permissible limit. The concept of “loading capacity” (LC) for Cr in paddy soil was then defined as the difference between the CT and the real concentration of Cr in paddy soil, so as to map the pollution risk of soil-Cr to rice grain and assess the risk areas in Jiaxing city, China. Compared with the information of the concentration of the total soil-Cr, such results are more valuable for spatial decision making in reducing the accumulation of rice-Cr at a regional scale. PMID:26675587

Assessing the pollution risk of soil Chromium based on loading capacity of paddy soil at a regional scale.

PubMed

Qu, Mingkai; Li, Weidong; Zhang, Chuanrong; Huang, Biao; Zhao, Yongcun

2015-12-17

The accumulation of a trace metal in rice grain is not only affected by the total concentration of the soil trace metal, but also by crop variety and related soil properties, such as soil pH, soil organic matter (SOM) and so on. However, these factors were seldom considered in previous studies on mapping the pollution risk of trace metals in paddy soil at a regional scale. In this study, the spatial nonstationary relationships between rice-Cr and a set of perceived soil properties (soil-Cr, soil pH and SOM) were explored using geographically weighted regression; and the relationships were then used for calculating the critical threshold (CT) of soil-Cr concentration that may ensure the concentration of rice-Cr being below the permissible limit. The concept of "loading capacity" (LC) for Cr in paddy soil was then defined as the difference between the CT and the real concentration of Cr in paddy soil, so as to map the pollution risk of soil-Cr to rice grain and assess the risk areas in Jiaxing city, China. Compared with the information of the concentration of the total soil-Cr, such results are more valuable for spatial decision making in reducing the accumulation of rice-Cr at a regional scale.

Widespread extrahippocampal NAA/(Cr+Cho) abnormalities in TLE with and without mesial temporal sclerosis.

PubMed

Mueller, Susanne G; Ebel, Andreas; Barakos, Jerome; Scanlon, Cathy; Cheong, Ian; Finlay, Daniel; Garcia, Paul; Weiner, Michael W; Laxer, Kenneth D

2011-04-01

MR spectroscopy has demonstrated extrahippocampal NAA/(Cr+Cho) reductions in medial temporal lobe epilepsy with (TLE-MTS) and without (TLE-no) mesial temporal sclerosis. Because of the limited brain coverage of those previous studies, it was, however, not possible to assess differences in the distribution and extent of these abnormalities between TLE-MTS and TLE-no. This study used a 3D whole brain echoplanar spectroscopic imaging (EPSI) sequence to address the following questions: (1) Do TLE-MTS and TLE-no differ regarding severity and distribution of extrahippocampal NAA/(Cr+Cho) reductions? (2) Do extrahippocampal NAA/(Cr+Cho) reductions provide additional information for focus lateralization? Forty-three subjects (12 TLE-MTS, 13 TLE-no, 18 controls) were studied with 3D EPSI. Statistical parametric mapping (SPM2) was used to identify regions of significantly decreased NAA/(Cr+Cho) in TLE groups and in individual patients. TLE-MTS and TLE-no had widespread extrahippocampal NAA/(Cr+Cho) reductions. NAA/(Cr+Cho) reductions had a bilateral fronto-temporal distribution in TLE-MTS and a more diffuse, less well defined distribution in TLE-no. Extrahippocampal NAA/(Cr+Cho) decreases in the single subject analysis showed a large inter-individual variability and did not provide additional focus lateralizing information. Extrahippocampal NAA/(Cr+Cho) reductions in TLE-MTS and TLE-no are neither focal nor homogeneous. This reduces their value for focus lateralization and suggests a heterogeneous etiology of extrahippocampal spectroscopic metabolic abnormalities in TLE.

Microstructure and Mechanical Properties of Cr-SiC Particles-Reinforced Fe-Based Alloy Coating

NASA Astrophysics Data System (ADS)

Wang, Fu-cheng; Du, Xiao-dong; Zhan, Ma-ji; Lang, Jing-wei; Zhou, Dan; Liu, Guang-fu; Shen, Jian

2015-12-01

In this study, SiC particles were first coated with Cr to form a layer that can protect the SiC particles from dissolution in the molten pool. Then, the Cr-SiC powder was injected into the tail of molten pool during plasma-transferred arc welding process (PTAW), where the temperature was relatively low, to prepare Cr-SiC particles reinforced Fe-based alloy coating. The microstructure and phase composition of the powder and surface coatings were analyzed, and the element distribution and hardness at the interfacial region were also evaluated. The protective layer consists of Cr3Si, Cr7C3, and Cr23C6, which play an important role in the microstructure and mechanical properties. The protective layer is dissolved in the molten pool forming a flocculent region and a transition region between the SiC particles and the matrix. The tribological performance of the coating was also assessed using a ring-block sliding wear tester with GGr15 grinding ring under 490 and 980 N load. Cr-SiC particles-reinforced coating has a lower wear rate than the unreinforced coating.

Pilot Assessment of Brain Metabolism in Perinatally HIV-Infected Youths Using Accelerated 5D Echo Planar J-Resolved Spectroscopic Imaging.

PubMed

Iqbal, Zohaib; Wilson, Neil E; Keller, Margaret A; Michalik, David E; Church, Joseph A; Nielsen-Saines, Karin; Deville, Jaime; Souza, Raissa; Brecht, Mary-Lynn; Thomas, M Albert

2016-01-01

To measure cerebral metabolite levels in perinatally HIV-infected youths and healthy controls using the accelerated five dimensional (5D) echo planar J-resolved spectroscopic imaging (EP-JRESI) sequence, which is capable of obtaining two dimensional (2D) J-resolved spectra from three spatial dimensions (3D). After acquisition and reconstruction of the 5D EP-JRESI data, T1-weighted MRIs were used to classify brain regions of interest for HIV patients and healthy controls: right frontal white (FW), medial frontal gray (FG), right basal ganglia (BG), right occipital white (OW), and medial occipital gray (OG). From these locations, respective J-resolved and TE-averaged spectra were extracted and fit using two different quantitation methods. The J-resolved spectra were fit using prior knowledge fitting (ProFit) while the TE-averaged spectra were fit using the advanced method for accurate robust and efficient spectral fitting (AMARES). Quantitation of the 5D EP-JRESI data using the ProFit algorithm yielded significant metabolic differences in two spatial locations of the perinatally HIV-infected youths compared to controls: elevated NAA/(Cr+Ch) in the FW and elevated Asp/(Cr+Ch) in the BG. Using the TE-averaged data quantified by AMARES, an increase of Glu/(Cr+Ch) was shown in the FW region. A strong negative correlation (r < -0.6) was shown between tCh/(Cr+Ch) quantified using ProFit in the FW and CD4 counts. Also, strong positive correlations (r > 0.6) were shown between Asp/(Cr+Ch) and CD4 counts in the FG and BG. The complimentary results using ProFit fitting of J-resolved spectra and AMARES fitting of TE-averaged spectra, which are a subset of the 5D EP-JRESI acquisition, demonstrate an abnormal energy metabolism in the brains of perinatally HIV-infected youths. This may be a result of the HIV pathology and long-term combinational anti-retroviral therapy (cART). Further studies of larger perinatally HIV-infected cohorts are necessary to confirm these findings.

Farm-level risk factors for the occurrence, new infection or persistence of tuberculosis in cattle herds from South-Central Spain.

PubMed

Martínez-López, B; Barasona, J A; Gortázar, C; Rodríguez-Prieto, V; Sánchez-Vizcaíno, J M; Vicente, J

2014-10-01

Eradication of tuberculosis (TB) in cattle is a priority in the EU. However, and despite the resources invested, TB eradication is still a goal yet to be accomplished. As a consequence, the identification of risk factors contributing to TB transmission and persistence is key to a better understand and, ultimately, more cost-effectively control and eradicate this complex zoonotic disease worldwide. This study aimed to identify the factors contributing to the TB occurrence, new infection, and persistence in one of the most TB-prevalent regions in the South-Central part of Spain (SCS), Ciudad Real (CR), and for which high quality and detailed information on cattle and wild ungulate demographics, management, and sanitary status was available for up to 5 years (2007-2011). Multilevel logistic modeling was used for this purpose. Results of this study revealed that the risk for TB (occurrence, new infection, and/or persistence) in cattle herds from CR is related to TB-persistence on farm in previous years, extensive production systems (beef and bullfighting being more risky that dairy) and large farm in terms of cattle number. Also, the presence and proximity of fenced hunting estates (which are usually intensively managed) significantly contributed to the risk of TB occurrence and persistence in CR. This association suggests that wild ungulates may play a role as TB-reservoirs and transmit TB to cattle in the CR, a region where TB is endemic and is associated with extensive farming of beef cattle. To the best of author's knowledge this is the first study to (i) evaluate the wild ungulate-domestic interface at a farm level using detailed information over an extensive region and period of time (2007-2011) and (ii) to identify a direct association between TB in cattle and the proximity and management practices of wild ungulates. Methods and results presented here may support policies to better prevent and control TB in the SCS and in other regions/countries with similar epidemiological conditions. Copyright © 2013 Elsevier B.V. All rights reserved.

Temporal Nodal Regression and Regional Control After Primary Radiation Therapy for N2-N3 Head-and-Neck Cancer Stratified by HPV Status

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, Shao Hui; O'Sullivan, Brian; Xu, Wei

Purpose: To compare the temporal lymph node (LN) regression and regional control (RC) after primary chemoradiation therapy/radiation therapy in human papillomavirus-related [HPV(+)] versus human papillomavirus-unrelated [HPV(−)] head-and-neck cancer (HNC). Methods and Materials: All cases of N2-N3 HNC treated with radiation therapy/chemoradiation therapy between 2003 and 2009 were reviewed. Human papillomavirus status was ascertained by p16 staining on all available oropharyngeal cancers. Larynx/hypopharynx cancers were considered HPV(−). Initial radiologic complete nodal response (CR) (≤1.0 cm 8-12 weeks after treatment), ultimate LN resolution, and RC were compared between HPV(+) and HPV(−) HNC. Multivariate analysis identified outcome predictors. Results: A total of 257more » HPV(+) and 236 HPV(−) HNCs were identified. The initial LN size was larger (mean, 2.9 cm vs 2.5 cm; P<.01) with a higher proportion of cystic LNs (38% vs 6%, P<.01) in HPV(+) versus HPV(−) HNC. CR was achieved is 125 HPV(+) HNCs (49%) and 129 HPV(−) HNCs (55%) (P=.18). The mean post treatment largest LN was 36% of the original size in the HPV(+) group and 41% in the HPV(−) group (P<.01). The actuarial LN resolution was similar in the HPV(+) and HPV(−) groups at 12 weeks (42% and 43%, respectively), but it was higher in the HPV(+) group than in the HPV(−) group at 36 weeks (90% vs 77%, P<.01). The median follow-up period was 3.6 years. The 3-year RC rate was higher in the HPV(−) CR cases versus non-CR cases (92% vs 63%, P<.01) but was not different in the HPV(+) CR cases versus non-CR cases (98% vs 92%, P=.14). On multivariate analysis, HPV(+) status predicted ultimate LN resolution (odds ratio, 1.4 [95% confidence interval, 1.1-1.7]; P<.01) and RC (hazard ratio, 0.3 [95% confidence interval 0.2-0.6]; P<.01). Conclusions: HPV(+) LNs involute more quickly than HPV(−) LNs but undergo a more prolonged process to eventual CR beyond the time of initial assessment at 8 to 12 weeks after treatment. Post radiation neck dissection is advisable for all non-CR HPV(−)/non-CR N3 HPV(+) cases, but it may be avoided for selected non-CR N2 HPV(+) cases with a significant LN involution if they can undergo continued imaging surveillance. The role of positron emission tomography for response assessment should be investigated.« less

Size Distribution and Estimated Respiratory Deposition of Total Chromium, Hexavalent Chromium, Manganese, and Nickel in Gas Metal Arc Welding Fume Aerosols

PubMed Central

Cena, Lorenzo G.; Chisholm, William P.; Keane, Michael J.; Cumpston, Amy; Chen, Bean T.

2016-01-01

A laboratory study was conducted to determine the mass of total Cr, Cr(VI), Mn, and Ni in 15 size fractions for mild and stainless steel gas-metal arc welding (GMAW) fumes. Samples were collected using a nano multi orifice uniform deposition impactor (MOUDI) with polyvinyl chloride filters on each stage. The filters were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) and ion chromatography. Limits of detection (LODs) and quantitation (LOQs) were experimentally calculated and percent recoveries were measured from spiked metals in solution and dry, certified welding-fume reference material. The fraction of Cr(VI) in total Cr was estimated by calculating the ratio of Cr(VI) to total Cr mass for each particle size range. Expected, regional deposition of each metal was estimated according to respiratory-deposition models. The weight percent (standard deviation) of Mn in mild steel fumes was 9.2% (6.8%). For stainless steel fumes, the weight percentages were 8.4% (5.4%) for total Cr, 12.2% (6.5%) for Mn, 2.1% (1.5%) for Ni and 0.5% (0.4%) for Cr(VI). All metals presented a fraction between 0.04 and 0.6 μm. Total Cr and Ni presented an additional fraction <0.03 μm. On average 6% of the Cr was found in the Cr(VI) valence state. There was no statistical difference between the smallest and largest mean Cr(VI) to total Cr mass ratio (p-value D 0.19), hence our analysis does not show that particle size affects the contribution of Cr(VI) to total Cr. The predicted total respiratory deposition for the metal particles was ∼25%. The sites of principal deposition were the head airways (7–10%) and the alveolar region (11–14%). Estimated Cr(VI) deposition was highest in the alveolar region (14%). PMID:26848207

Size Distribution and Estimated Respiratory Deposition of Total Chromium, Hexavalent Chromium, Manganese, and Nickel in Gas Metal Arc Welding Fume Aerosols.

PubMed

Cena, Lorenzo G; Chisholm, William P; Keane, Michael J; Cumpston, Amy; Chen, Bean T

A laboratory study was conducted to determine the mass of total Cr, Cr(VI), Mn, and Ni in 15 size fractions for mild and stainless steel gas-metal arc welding (GMAW) fumes. Samples were collected using a nano multi orifice uniform deposition impactor (MOUDI) with polyvinyl chloride filters on each stage. The filters were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) and ion chromatography. Limits of detection (LODs) and quantitation (LOQs) were experimentally calculated and percent recoveries were measured from spiked metals in solution and dry, certified welding-fume reference material. The fraction of Cr(VI) in total Cr was estimated by calculating the ratio of Cr(VI) to total Cr mass for each particle size range. Expected, regional deposition of each metal was estimated according to respiratory-deposition models. The weight percent (standard deviation) of Mn in mild steel fumes was 9.2% (6.8%). For stainless steel fumes, the weight percentages were 8.4% (5.4%) for total Cr, 12.2% (6.5%) for Mn, 2.1% (1.5%) for Ni and 0.5% (0.4%) for Cr(VI). All metals presented a fraction between 0.04 and 0.6 μ m. Total Cr and Ni presented an additional fraction <0.03 μ m. On average 6% of the Cr was found in the Cr(VI) valence state. There was no statistical difference between the smallest and largest mean Cr(VI) to total Cr mass ratio ( p -value D 0.19), hence our analysis does not show that particle size affects the contribution of Cr(VI) to total Cr. The predicted total respiratory deposition for the metal particles was ∼25%. The sites of principal deposition were the head airways (7-10%) and the alveolar region (11-14%). Estimated Cr(VI) deposition was highest in the alveolar region (14%).

The effect of grain boundary chemistry on Intergranular stress corrosion cracking of Ni-Cr-Fe alloys in 50 Pct NaOH at 140 °C

NASA Astrophysics Data System (ADS)

Sung, J. K.; Koch, J.; Angeliu, T.; Was, G. S.

1992-10-01

The role of chromium, carbon, chromium carbides, and phosphorus on the intergranular stress corrosion cracking (IGSCC) resistance of Ni-Cr-Fe alloys in 50 pct NaOH at 140 °C is studied using controlled-purity alloys. The effect of carbon is studied using heats in which the carbon level is varied between 0.002 and 0.063 wt pct while the Cr level is fixed at 16.8 wt pct. The effect of Cr is studied using alloys with Cr concentrations between 5 and 30 wt pct. The effect of grain boundary Cr and C together is studied by heat-treating the nominal alloy composition of Ni-16Cr-9Fe-0.035C, and the effect of P is studied using a high-purity, P-doped alloy and a carbon-containing, P-doped alloy. Constant extension rate tensile (CERT) results show that the crack depth increases with decreasing alloy Cr content and increasing alloy C content. Crack- ing severity also correlates inversely with thermal treatment time at 700 °C, during which the grain boundary Cr content rises and the grain boundary C content falls. Phosphorus is found to have a slightly beneficial effect on IG cracking susceptibility. Potentiodynamic polarization and potentiostatic current decay experiments confirm that Cr depletion or grain boundary C enhances the dissolution at the grain boundary. Results support a film rupture-anodic dissolution model in which Cr depletion or grain boundary C (independently or additively) enhances dissolution of nickel from the grain boundary region and leads to increased IG cracking.

Alzheimer Disease Alters the Relationship of Cardiorespiratory Fitness With Brain Activity During the Stroop Task

PubMed Central

Gayed, Matthew R.; Honea, Robyn A.; Savage, Cary R.; Hobbs, Derek; Burns, Jeffrey M.

2013-01-01

Background Despite mounting evidence that physical activity has positive benefits for brain and cognitive health, there has been little characterization of the relationship between cardiorespiratory (CR) fitness and cognition-associated brain activity as measured by functional magnetic resonance imaging (fMRI). The lack of evidence is particularly glaring for diseases such as Alzheimer disease (AD) that degrade cognitive and functional performance. Objective The aim of this study was to describe the relationship between regional brain activity during cognitive tasks and CR fitness level in people with and without AD. Design A case-control, single-observation study design was used. Methods Thirty-four individuals (18 without dementia and 16 in the earliest stages of AD) completed maximal exercise testing and performed a Stroop task during fMRI. Results Cardiorespiratory fitness was inversely associated with anterior cingulate activity in the participants without dementia (r=−.48, P=.05) and unassociated with activation in those with AD (P>.7). Weak associations of CR fitness and middle frontal cortex were noted. Limitations The wide age range and the use of a single task in fMRI rather than multiple tasks challenging different cognitive capacities were limitations of the study. Conclusions The results offer further support of the relationship between CR fitness and regional brain activity. However, this relationship may be attenuated by disease. Future work in this area may provide clinicians and researchers with interpretable and dependable regional fMRI biomarker signatures responsive to exercise intervention. It also may shed light on mechanisms by which exercise can support cognitive function. PMID:23559521

Evaluation of the effects of food on levodropropizine controlled-release tablet and its pharmacokinetic profile in comparison to that of immediate-release tablet.

PubMed

Lee, Soyoung; Nam, Kyu-Yeol; Oh, Jaeseong; Lee, SeungHwan; Cho, Sang-Min; Choi, Youn-Woong; Cho, Joo-Youn; Lee, Beom-Jin; Hong, Jang Hee

2018-01-01

Levodropropizine is a non-opioid antitussive agent that inhibits cough reflex by reducing the release of sensory peptide in the peripheral region. To improve patients' compliance, a controlled-release (CR) tablet is under development. The aim of this study was to compare the pharmacokinetic (PK) profiles of the CR and immediate-release (IR) tablets of levodropropizine. In addition, the effect of food on the PK properties of levodropropizine CR tablet in healthy subjects was evaluated. A randomized, open-label, multiple-dose, three-treatment, three-period, six-sequence, crossover study was conducted on 47 healthy subjects. All subjects were randomly assigned to one of the six sequences, which involve combinations of the following three treatments: levodropropizine IR 60 mg three times in the fasted state (R), levodropropizine CR 90 mg two times in the fasted state (T), and levodropropizine CR 90 mg two times in the fed state (TF). Serial blood samples were collected up to 24 h after the first dose. Tolerability was assessed based on the vital signs, adverse events (AEs), and clinical laboratory tests. Levodropropizine CR showed lower maximum drug concentration ( C max ) and similar total exposure compared to levodropropizine IR. The geometric mean ratios (GMRs) (90% confidence intervals [CIs]) of T to R for the C max and area under the concentration-time curve from the 0 to 24 h time points (AUC 0-24h ) were 0.80 (0.75-0.85) and 0.89 (0.86-0.93), respectively. In the fed group, levodropropizine CR showed exposure similar to that in the fasted group. The GMRs (90% CIs) of TF to T for the C max and AUC 0-24h were 0.90 (0.85-0.97) and 1.10 (1.05-1.14), respectively. No serious AEs occurred with both levodropropizine CR and IR tablets. Total systemic exposure for levodropropizine was similar in subjects receiving the CR and IR formulations in terms of the AUC. Although food delayed the absorption of levodropropizine CR, systemic exposure was not affected.

A NUMERICAL SIMULATION OF COSMIC RAY MODULATION NEAR THE HELIOPAUSE. II. SOME PHYSICAL INSIGHTS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luo, Xi; Feng, Xueshang; Potgieter, Marius S.

Cosmic ray (CR) transport near the heliopause (HP) is studied using a hybrid transport model, with the parameters constrained by observations from the Voyager 1 spacecraft. We simulate the CR radial flux along different directions in the heliosphere. There is no well-defined thin layer between the solar wind region and the interstellar region along the tail and polar directions of the heliosphere. By analyzing the radial flux curve along the direction of Voyager 2 , together with its trajectory information, the crossing time of the HP by Voyager 2 is predicted to be in 2017.14. We simulate the CR radialmore » flux for different energy values along the direction of Voyager 1 . We find that there is only a modest modulation region of about 10 au wide beyond the HP, so that Voyager 1 observing the Local Interstellar Spectra is justified in numerical modeling. We analyze the heliospheric exit information of pseudo-particles in our stochastic numerical (time-backward) method, conjecturing that they represent the behavior of CR particles, and we find that pseudo-particles that have been traced from the nose region exit in the tail region. This implies that many CR particles diffuse directly from the heliospheric tail region to the nose region near the HP. In addition, when pseudo-particles were traced from the Local Interstellar Medium (LISM), it is found that their exit location (entrance for real particles) from the simulation domain is along the prescribed Interstellar Magnetic Field direction. This indicates that parallel diffusion dominates CR particle transport in the LISM.« less

High-temperature corrosion of UNS N10003 in molten Li 2BeF 4 (FLiBe) salt

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zheng, Guiqiu; Kelleher, Brian; He, Lingfeng

2015-07-30

Here, corrosion testing of Hastelloy N in molten fluoride salt was performed in purified molten 2 7LiF-BeF 2 (66-34mol%) (FLiBe) salt at 700°C for 1000 hours, in pure nickel and graphite capsules. In the nickel capsule tests, the near-surface region of the alloy exhibited an about 200 nm porous structure, an approximately 3.5 μm chromium depleted region, and MoSi 2 precipitates. In tests performed in graphite capsules, the alloy samples gained weight due to the formation of a variety of Cr 3C 2, Cr 7C 3, Mo 2C and Cr 23C 6, carbide phases on the surface and in themore » subsurface regions of the alloy. A Cr depleted region was observed in the near-surface region where Mo thermally diffused toward either surface or grain boundary, which induced approximately 1.4 μm Ni 3Fe alloy layer in this region. The carbide containing layer extended to about 7 μm underneath the Ni 3Fe layer. The presence of graphite dramatically changes the mechanisms of corrosion attack in Hastelloy N in molten FLiBe salt. Evaluated by in terms of the depth of attack, graphite clearly accelerates corrosion, but the results appear to indicate that the formation of Cr 23C 6 phase might stabilize the Cr and mitigate its dissolution in molten FLiBe salt.« less

An Open-Label Exploratory Study with Memantine: Correlation between Proton Magnetic Resonance Spectroscopy and Cognition in Patients with Mild to Moderate Alzheimer's Disease

PubMed Central

Gordon, Marc L.; Kingsley, Peter B.; Goldberg, Terry E.; Koppel, Jeremy; Christen, Erica; Keehlisen, Lynda; Kohn, Nina; Davies, Peter

2012-01-01

Aim To characterize progression of Alzheimer's disease (AD) using proton magnetic resonance spectroscopy (1H MRS). Methods Eleven subjects with mild to moderate AD underwent neurocognitive testing and single-voxel 1H MRS from the precuneus and posterior cingulate region at baseline, after 24 weeks of monotherapy with a cholinesterase inhibitor, and after another 24 weeks of combination therapy with open-label memantine and a cholinesterase inhibitor. Baseline metabolites [N-acetylaspartate (NAA), myo-inositol (mI), choline (Cho), and creatine (Cr)] and their ratios in AD subjects were compared with those of an age-matched control group of 28 cognitively normal subjects. Results AD subjects had significantly higher mI/Cr and lower NAA, NAA/Cr, NAA/Cho, and NAA/mI. Baseline Alzheimer's Disease Cooperative Study Activities of Daily Living (ADCS-ADL) scores significantly correlated with NAA/Cr, mI/Cr, and NAA/mI. There was an increase in mI and a decrease in NAA/mI, but no significant change in other metabolites or ratios, or neurocognitive measures, when memantine was added to a cholinesterase inhibitor. Conclusion Metabolite ratios significantly differed between AD and control subjects. Baseline metabolite ratios correlated with function (ADCS-ADL). There was an increase in mI and a decrease in NAA/mI, but no changes in other metabolites, ratios, or cognitive measures, when memantine was added to a cholinesterase inhibitor. PMID:22962555

Synchrotron-based imaging of chromium and γ-H2AX immunostaining in the duodenum following repeated exposure to Cr(VI) in drinking water.

PubMed

Thompson, Chad M; Seiter, Jennifer; Chappell, Mark A; Tappero, Ryan V; Proctor, Deborah M; Suh, Mina; Wolf, Jeffrey C; Haws, Laurie C; Vitale, Rock; Mittal, Liz; Kirman, Christopher R; Hays, Sean M; Harris, Mark A

2015-01-01

Current drinking water standards for chromium are for the combined total of both hexavalent and trivalent chromium (Cr(VI) and Cr(III)). However, recent studies have shown that Cr(III) is not carcinogenic to rodents, whereas mice chronically exposed to high levels of Cr(VI) developed duodenal tumors. These findings may suggest the need for environmental standards specific for Cr(VI). Whether the intestinal tumors arose through a mutagenic or non-mutagenic mode of action (MOA) greatly impacts how drinking water standards for Cr(VI) are derived. Herein, X-ray fluorescence (spectro)microscopy (µ-XRF) was used to image the Cr content in the villus and crypt regions of duodena from B6C3F1 mice exposed to 180 mg/l Cr(VI) in drinking water for 13 weeks. DNA damage was also assessed by γ-H2AX immunostaining. Exposure to Cr(VI) induced villus blunting and crypt hyperplasia in the duodenum--the latter evidenced by lengthening of the crypt compartment by ∼2-fold with a concomitant 1.5-fold increase in the number of crypt enterocytes. γ-H2AX immunostaining was elevated in villi, but not in the crypt compartment. µ-XRF maps revealed mean Cr levels >30 times higher in duodenal villi than crypt regions; mean Cr levels in crypt regions were only slightly above background signal. Despite the presence of Cr and elevated γ-H2AX immunoreactivity in villi, no aberrant foci indicative of transformation were evident. These findings do not support a MOA for intestinal carcinogenesis involving direct Cr-DNA interaction in intestinal stem cells, but rather support a non-mutagenic MOA involving chronic wounding of intestinal villi and crypt cell hyperplasia. © The Author 2014. Published by Oxford University Press on behalf of the Society of Toxicology.

Effects of strain and buffer layer on interfacial magnetization in Sr 2 CrReO 6 films determined by polarized neutron reflectometry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Yaohua; Lucy, J. M.; Glavic, A.

2014-09-01

We have determined the depth-resolved magnetization structures of a series of highly orderedSr2CrReO6 (SCRO) ferrimagnetic epitaxial films via combined studies of x-ray reflectometry, polarized neutron reflectometry and SQUID magnetometry. The SCRO films deposited directly on (LaAlO3)0:3(Sr2AlTaO6)0:7 or SrTiO3 substrates show reduced magnetization of similar width near the interfaces with the substrates, despite having different degrees of strain. When the SCRO film is deposited on a Sr2CrNbO6 (SCNO) double perovskite buffer layer, the width the interfacial region with reduced magnetization is reduced, agreeing with an improved Cr/Re ordering. However, the relative reduction of the magnetization averaged over the interfacial regions aremore » comparable among the three samples. Interestingly, we found that the magnetization suppression region is wider than the Cr/Re antisite disorder region at the interface between SCRO and SCNO.« less

Experience of diffusion tensor imaging and 1H spectroscopy for outcome prediction in severe traumatic brain injury: Preliminary results.

PubMed

Tollard, Eléonore; Galanaud, Damien; Perlbarg, Vincent; Sanchez-Pena, Paola; Le Fur, Yann; Abdennour, Lamine; Cozzone, Patrick; Lehericy, Stéphane; Chiras, Jacques; Puybasset, Louis

2009-04-01

The objective of the study is to test whether multimodal magnetic resonance imaging can provide a reliable outcome prediction of the clinical status, focusing on consciousness at 1 year after severe traumatic brain injury (TBI). Single center prospective cohort with consecutive inclusions. Critical Care Neurosurgical Unit of a university hospital. Forty-three TBI patients not responding to simple orders after sedation cessation and 15 healthy controls. A multimodal magnetic resonance imaging combining morphologic sequences, diffusion tensor imaging (DTI), and H proton magnetic resonance spectroscopy (MRS) was performed 24 +/- 11 days after severe TBI. The ability of DTI and MRS to predict 1-year outcome was assessed by linear discriminant analysis (LDA). Robustness of the classification was tested using a bootstrap procedure. Fractional anisotropy (FA) was computed as the mean of values at discrete brain sites in the infratentorial and supratentorial regions. The N-acetyl aspartate/creatine (NAA/Cr) ratio was measured in the thalamus, lenticular nucleus, insular cortex, occipital periventricular white matter, and pons. After 1 year, 19 (44%) patients had unfavorable outcomes (death, persistent vegetative state, or minimally conscious state) and 24 (56%) favorable outcomes (normal consciousness with or without functional impairments). Analysis of variance was performed to compare FA and NAA/Cr in the two outcome groups and controls. FA and MRS findings showed highly significant differences between the outcome groups, with significant variables by LDA being supratentorial FA, NAA/Cr (pons), NAA/Cr (thalamus), NAA/Cr (insula), and infratentorial FA. LDA of combined FA and MRS data clearly separated the unfavorable outcome, favorable outcome, and control groups, with no overlap. Unfavorable outcome was predicted with up to 86% sensitivity and 97% specificity; these values were better than those obtained with DTI or MRS alone. FA and NAA/Cr hold potential as quantitative outcome-prediction tools at the subacute phase of TBI.

Heavy metal pollution and health risk assessment in the Wei River in China.

PubMed

Yang, Xuefu; Duan, Jinming; Wang, Lei; Li, Wei; Guan, Jianling; Beecham, Simon; Mulcahy, Dennis

2015-03-01

From data collected monthly at 26 monitoring cross sections in the Wei River in the Shaanxi Region of China during the period 2008-2012, the temporal pollution characteristics of heavy metals (Hg, Cd, Cr(VI), Pb, and As) were analyzed based on a heavy metal pollution index (HPI). The monthly HPI values of the five heavy metals in the river fluctuated greatly in 2008 and then declined gradually with time. This general trend of reduction in HPI appears not to have a seasonal variation and most likely resulted from the continued improvement in heavy metal pollution control strategies implemented by local environmental agencies combined with a significant improvement in wastewater treatment capacities. Among the five heavy metals, Cd and Pb were below 0.1 and 3 μg L(-1), respectively, at all the sampling points in the studied areas in the year 2012. The detection rates of As, Hg, and Cr(VI) were in the order of Hg > Cr(VI) > As. Hg, Cr(VI), and As exceeded, in a month of the dry season in 2012, the standard limits for category III surface waters according to the China Environment Quality Standards for Surface Water (CEQSSW). Based on the assessment using the HPI method, the pollution status of these heavy metals in water of the Wei River in the Shaanxi Region was generally at an acceptable level, but exhibited distinctive characteristics between the main stream river and tributaries. Most of the tributaries were more seriously polluted than the main river. A health risk assessment was conducted based on the Human Health Risk Assessment (HHRA) method recommended by the United States Environmental Protection Agency (USEPA). Apart from As, the health risk for the five heavy metals in the region were at acceptable levels for drinking water sources (hazard quotient (HQ) < 1, carcinogenic risk (CR) ranged from 10(-4)-10(-6)) according to the Risk Assessment Guidance for Superfund (RAGS), USEPA. Arsenic was identified as the most important pollutant of concern among the five heavy metals; both its values of the HQ and CR indicated potentially adverse health risks for the local population.

Multiscale Characterization of Microstructure in Near-Surface Regions of a 16MnCr5 Gear Wheel After Cyclic Loading

NASA Astrophysics Data System (ADS)

Medghalchi, Setareh; Jamebozorgi, Vahid; Bala Krishnan, Arjun; Vincent, Smobin; Salomon, Steffen; Basir Parsa, Alireza; Pfetzing, Janine; Kostka, Aleksander; Li, Yujiao; Eggeler, Gunther; Li, Tong

2018-05-01

The dependence of the microstructure on the degree of deformation in near-surface regions of a 16MnCr5 gear wheel after 2.1 × 106 loading cycles has been investigated by x-ray diffraction analysis, transmission electron microscopy, and atom probe tomography. Retained austenite and large martensite plates, along with elongated lamella-like cementite, were present in a less deformed region. Comparatively, the heavily deformed region consisted of a nanocrystalline structure with carbon segregation up to 2 at.% at grain boundaries. Spheroid-shaped cementite, formed at the grain boundaries and triple junctions of the nanosized grains, was enriched with Cr and Mn but depleted with Si. Such partitioning of Cr, Mn, and Si was not observed in the elongated cementite formed in the less deformed zone. This implies that rolling contact loading induced severe plastic deformation as well as a pronounced annealing effect in the active contact region of the toothed gear during cyclic loading.

The complete mitochondrial genome sequence of the Tibetan red fox (Vulpes vulpes montana).

PubMed

Zhang, Jin; Zhang, Honghai; Zhao, Chao; Chen, Lei; Sha, Weilai; Liu, Guangshuai

2015-01-01

In this study, the complete mitochondrial genome of the Tibetan red fox (Vulpes Vulpes montana) was sequenced for the first time using blood samples obtained from a wild female red fox captured from Lhasa in Tibet, China. Qinghai--Tibet Plateau is the highest plateau in the world with an average elevation above 3500 m. Sequence analysis showed it contains 12S rRNA gene, 16S rRNA gene, 22 tRNA genes, 13 protein-coding genes and 1 control region (CR). The variable tandem repeats in CR is the main reason of the length variability of mitochondrial genome among canide animals.

Structural, electronic transport and optical properties of Cr doped PbS thin film by chemical bath deposition

NASA Astrophysics Data System (ADS)

Preetha, K. C.

2017-06-01

Incorporation of Chromium ions into Lead Sulphide thin films have been achieved by CBD technique. Effects of doping were investigated as a function of Pb/Cr ratio from o to 2 at %. X-ray diffraction patterns showed that films were polycrystalline in nature with increase in crystallite size up to an optimum doping concentration. Scanning electron microscopic study revealed excellent morphology with doping concentration. The low transmittance in the UV-VIS region offered the suitability of the samples as solar control coatings. The thin films were found to be P type and electrical conductivity enhanced on doping.

Effects of Supplemental Chromium Source and Concentration on Growth Performance, Carcass Traits, and Meat Quality of Broilers Under Heat Stress Conditions.

PubMed

Huang, Yanling; Yang, Jian; Xiao, Fang; Lloyd, Karen; Lin, Xi

2016-03-01

The objective of this study was to investigate the effects of dietary supplemental chromium (Cr) on growth performance, carcass traits, and meat quality of broilers reared under heat stress. A total of 252 1-d-old Cobb 500 commercial female broilers were randomly allotted by body weight (BW) to one of six replicate cages (six broilers per cage) for each of seven treatments in a completely randomized design involving a 2 × 3 factorial arrangement of treatments with three Cr sources (Cr propionate, CrPro; Cr picolinate, CrPic; Cr chloride, CrCl3) and two concentrations of added Cr (0.4, or 2.0 mg of Cr/kg) plus a Cr-unsupplemented control group. Feed and distilled-deionized water were available ad libitum for an experimental phase of 42 days. For induction of heat stress, the house temperature was set at 33 ± 2 °C from 15 to 42 days of age. Results showed that birds supplemented with Cr, regardless of Cr source, had increased ADG (P = 0.032) than controls. Birds fed 2.0 mg Cr/kg diet had greater ADG (P = 0.005) than birds fed 0.4 mg Cr/kg diet. Compared to controls, birds fed with Cr had greater dressing percentage (P = 0.021). Percentage of abdominal fat decreased (P = 0.013), whereas, breast intramuscular fat (IMF) remained unaffected (P = 0.147) in Cr supplemented vs control broilers. Broilers supplemented Cr had decreased b* values of meat color (P = 0.042) in breast muscle. B*values were also lesser (P = 0.049) in birds fed CrPro than birds supplemented with CrCl3 or CrPic. Regardless of Cr source, the percentage of cooking loss was decreased (P = 0.025) with Cr supplementation in breast muscle when compared to controls. Results from this study indicate that Cr supplementation, independent of its source, could promote growth and improve carcass traits and meat quality of broilers under heat stress conditions. Chromium propionate seems to have greater beneficial effects on meat color in comparison with CrPic and CrCl3.

Comparative Study of the Three-Dimensional Thermodynamical Structure of the Inner Corona of Solar Minimum Carrington Rotations 1915 and 2081

NASA Astrophysics Data System (ADS)

Lloveras, Diego G.; Vásquez, Alberto M.; Nuevo, Federico A.; Frazin, Richard A.

2017-10-01

Using differential emission measure tomography (DEMT) based on time series of EUV images, we carry out a quantitative comparative analysis of the three-dimensional (3D) structure of the electron density and temperature of the inner corona (r<1.25 R_{⊙}) between two specific rotations selected from the last two solar minima, namely Carrington Rotations (CR)1915 and CR-2081. The analysis places error bars on the results because of the systematic uncertainty of the sources. While the results for CR-2081 are characterized by a remarkable north-south symmetry, the southern hemisphere for CR-1915 exhibits higher densities and temperatures than the northern hemisphere. The core region of the streamer belt in both rotations is found to be populated by structures whose temperature decreases with height (called "down loops" in our previous articles). They are characterized by plasma β≳1, and may be the result of the efficient dissipation of Alfvén waves at low coronal heights. The comparative analysis reveals that the low latitudes of the equatorial streamer belt of CR-1915 exhibit higher densities than for CR-2081. This cannot be explained by the systematic uncertainties. In addition, the southern hemisphere of the streamer belt of CR-1915 is characterized by higher temperatures and density scale heights than for CR-2081. On the other hand, the coronal hole region of CR-1915 shows lower temperatures than for CR-2081. The reported differences are in the range ≈ 10 - 25%, depending on the specific physical quantity and region that is compared, as fully detailed in the analysis. For other regions and/or physical quantities, the uncertainties do not allow assessing the thermodynamical differences between the two rotations. Future investigation will involve a DEMT analysis of other Carrington rotations selected from both epochs, and also a comparison of their tomographic reconstructions with magnetohydrodynamical simulations of the inner corona.

Novel rabies virus-neutralizing epitope recognized by human monoclonal antibody: fine mapping and escape mutant analysis.

PubMed

Marissen, Wilfred E; Kramer, R Arjen; Rice, Amy; Weldon, William C; Niezgoda, Michael; Faber, Milosz; Slootstra, Jerry W; Meloen, Rob H; Clijsters-van der Horst, Marieke; Visser, Therese J; Jongeneelen, Mandy; Thijsse, Sandra; Throsby, Mark; de Kruif, John; Rupprecht, Charles E; Dietzschold, Bernhard; Goudsmit, Jaap; Bakker, Alexander B H

2005-04-01

Anti-rabies virus immunoglobulin combined with rabies vaccine protects humans from lethal rabies infections. For cost and safety reasons, replacement of the human or equine polyclonal immunoglobulin is advocated, and the use of rabies virus-specific monoclonal antibodies (MAbs) is recommended. We produced two previously described potent rabies virus-neutralizing human MAbs, CR57 and CRJB, in human PER.C6 cells. The two MAbs competed for binding to rabies virus glycoprotein. Using CR57 and a set of 15-mer overlapping peptides covering the glycoprotein ectodomain, a neutralization domain was identified between amino acids (aa) 218 and 240. The minimal binding region was identified as KLCGVL (aa 226 to 231), with key residues K-CGV- identified by alanine replacement scanning. The critical binding region of this novel nonconformational rabies virus epitope is highly conserved within rabies viruses of genotype 1. Subsequently, we generated six rabies virus variants escaping neutralization by CR57 and six variants escaping CRJB. The CR57 escape mutants were only partially covered by CRJB, and all CRJB-resistant variants completely escaped neutralization by CR57. Without exception, the CR57-resistant variants showed a mutation at key residues within the defined minimal binding region, while the CRJB escape viruses showed a single mutation distant from the CR57 epitope (N182D) combined with mutations in the CR57 epitope. The competition between CR57 and CRJB, the in vitro escape profile, and the apparent overlap between the recognized epitopes argues against including both CR57 and CRJB in a MAb cocktail aimed at replacing classical immunoglobulin preparations.

Selenium-methionine and chromium-methionine supplementation of sheep around parturition: impacts on dam and offspring performance.

PubMed

Mousaie, Amir; Valizadeh, Reza; Chamsaz, Mahmoud

2017-04-01

To examine the effects of maternal energy restriction along with selenium-methionine (Se-Met) and chromium-methionine (Cr-Met) supplementation on performance of pregnant sheep and their offspring, the following treatments were allotted randomly to 40 multiparous Baluchi ewes (53.9 ± 1.15 kg of body weight [BW]) from 5 weeks prior to 5 weeks after parturition: (1) Control diet (60% and 100% of NRC energy requirements in pre- and post-partum, respectively); (2) Control diet plus 5 mg Se-Met/kg dry matter (DM); (3) Control diet plus 3 mg Cr-Met/kg DM and (4) Control diet plus 5 mg Se-Met and 3 mg Cr-Met/kg DM (Se-Cr-Met) of concentrate diet. The results indicated that Cr-Met alone or in combination with Se-Met increased average DM intake of ewes. In addition, Group Cr-Met had higher average BW than the Control (p < 0.05). Se-Met and/or Cr-Met supplementation led to decreased average serum cholesterol of the ewes (p < 0.05). Groups Cr-Met and Se-Cr-Met displayed decreased average serum malondialdehyde compared to the Control (p < 0.05). At 24 h post-partum, Group Se-Cr-Met had a greater serum Se content than the Control (p = 0.006). Compared with the Control, the Se concentration in milk was significantly increased from 30 to 138 µg/l and 197 µg/l in Groups Se-Met and Se-Cr-Met, respectively (p < 0.01), which proved that Se-Met supplementation can increase the Se concentration of ewe milk. Furthermore, feeding Cr-Met may attenuate BW loss post-partum and Se-Met and/or Cr-Met supplements may ameliorate oxidative stress condition in ewes around parturition.

Chromium isotope variation along a contaminated groundwater plume: a coupled Cr(VI)- reduction, advective mixing perspective

NASA Astrophysics Data System (ADS)

Bullen, T.; Izbicki, J.

2007-12-01

Chromium (Cr) is a common contaminant in groundwater, used in electroplating, leather tanning, wood preservation, and as an anti-corrosion agent. Cr occurs in two oxidation states in groundwater: Cr(VI) is highly soluble and mobile, and is a carcinogen; Cr(III) is generally insoluble, immobile and less toxic than Cr(VI). Reduction of Cr(VI) to Cr(III) is thus a central issue in approaches to Cr(VI) contaminant remediation in aquifers. Aqueous Cr(VI) occurs mainly as the chromate (CrO22-) and bichromate (HCrO2-) oxyanions, while Cr(III) is mainly "hexaquo" Cr(H2O)63+. Cr has four naturally-occurring stable isotopes: 50Cr, 52Cr, 53Cr and 54Cr. When Cr(VI) is reduced to Cr(III), the strong Cr-O bond must be broken, resulting in isotopic selection. Ellis et al. (2002) demonstrated that for reduction of Cr(VI) on magnetite and in natural sediment slurries, the change of isotopic composition of the remnant Cr(VI) pool was described by a Rayleigh fractionation model having fractionation factor ɛCr(VI)-Cr(III) = 3.4‰. We attempted to use Cr isotopes as a monitor of Cr(VI) reduction at a field site in Hinkley, California (USA) where groundwater contaminated with Cr(VI) has been under assessment for remediation. Groundwater containing up to 5 ppm Cr(VI) has migrated down-gradient from the contamination source through the fluvial to alluvial sediments to form a well-defined plume. Uncontaminated groundwater in the aquifer immediately adjacent to the plume has naturally-occurring Cr(VI) of 4 ppb or less (CH2M-Hill). In early 2006, colleagues from CH2M-Hill collected 17 samples of groundwater from within and adjacent to the plume. On a plot of δ53Cr vs. log Cr(VI), the data array is strikingly linear and differs markedly from the trend predicted for reduction of Cr(VI) in the contaminated water. There appear to be two groups of data: four samples with δ53Cr >+2‰ and Cr(VI) <4 ppb, and 13 samples with δ53Cr <+2‰ and Cr(VI) >15 ppb. Simple mixing lines between the groundwater samples having <4 ppb Cr(VI), taken to be representative of regional groundwater, and the contaminated water do not pass through the remainder of the data, discounting a simple advective mixing scenario. We hypothesize a more likely scenario that involves both Cr(VI) reduction and advective mixing. As the plume initially expands downgradient, Cr(VI) in water at the leading edge encounters reductant in the aquifer resulting in limited Cr(VI) reduction. As a result of reduction, δ53Cr of Cr(VI) remaining in solution at the leading edge increases along the "reduction" trend from 0 to ~+2‰. Inevitable mixing of this water at the leading edge with regional groundwater results in a suitable mixing end-member to combine with Cr(VI) within the plume in order to explain the bulk of the remaining data. Neither Cr(VI) reduction nor advective mixing of plume and regional groundwaters can explain the data on their own, implying an interplay of at least these two processes during plume evolution. Ellis, A.S., Johnson, T.M. and Bullen, T.D. 2002, Science, 295, 2060-2062.

Cathodoluminescence microscopy and spectroscopy of forsterite from Kaba meteorite: An application to the study of hydrothermal alteration of parent body

NASA Astrophysics Data System (ADS)

Gucsik, Arnold; Endo, Taro; Nishido, Hirotsugu; Ninagawa, Kiyotaka; Kayama, Masahiro; Bérczi, Szaniszló; Nagy, Szabolcs; Ábrahám, Péter; Kimura, Yuki; Miura, Hitoshi; Gyollai, Ildikó; Simonia, Irakli; Rózsa, Péter; Posta, József; Apai, Dániel; Mihályi, Krisztián; Nagy, Mihály; Ott, Ulrich

2013-12-01

Highly forsteritic olivine (Fo: 99.2-99.7) in the Kaba meteorite emits bright cathodoluminescence (CL). CL spectra of red luminescent forsterite grains have two broad emission bands at approximately 630 nm (impurity center of divalent Mn ions) in the red region and above 700 nm (trivalent Cr ions) in the red-IR region. The cores of the grains show CL blue luminescence giving a characteristic broad band emission at 400 nm, also associated with minor red emissions related to Mn and Cr ions. CL color variation of Kaba forsterite is attributed to structural defects. Electron probe microanalyzer (EPMA) analysis shows concentrations of Ca, Al, and Ti in the center of the forsterite grain. The migration of diffusible ions of Mn, Cr, and Fe to the rim of the Kaba meteoritic forsterite was controlled by the hydrothermal alteration at relatively low temperature (estimated at about 250 °C), while Ca and Al ions might still lie in the core. A very unusual phase of FeO (wüstite) was also observed, which may be a terrestrial alteration product of FeNi-metal.

Systematics of melt stagnation in peridotites from the Godzilla Megamullion

NASA Astrophysics Data System (ADS)

Loocke, M.; Snow, J. E.; Ohara, Y.

2010-12-01

The Godzilla Megamullion (GM) Massif is the largest known example of an Oceanic Core Complex (OCC) or the exhumed footwall of a low angle-large offset oceanic detachment fault. It lies on the extinct Parece Vela Rift spreading center within the Parece Vela Back-arc Basin of the Philippine Sea. This has thus allowed for sampling of a young back-arc mantle section. Sampling of the massif has returned a dominantly ultramafic lithology, divided petrographically into depleted, fertile, and melt-percolated groups (1). Petrographic analysis of the extant peridotite thin section collection found that 44% of all GM peridotites (71 out of 161) exhibit evidence of plagioclase impregnation compared to the worldwide abyssal peridotite average of ~20% (2). The mullion is divided up into three regions, the proximal region ( closest to termination of spreading), the medial region, and the distal region (furthest from the termination of spreading)(3).Observations by region provide that 53% ( 62 out of 116 samples) in the proximal region (15 dredges), 12% ( 2 out of 17 samples) in the medial mullion (3 dredges), and 25% (7 out of 28) in the distal mullion (5 dredges) show of evidence of plagioclase impregnation (4). Major element analyses of spinels were completed using the Cameca SX-50 Electron Microprobe facility at the University of Houston. The Cr# [100 x Cr/(Cr + Al)] ranges from 10 to 65 with TiO2 concentrations ranging from less than 0.01 up to 1.6 wt%. When the Cr#s of the samples are plotted along the massif, a pattern of melt depletion exists that is consistent with the degree of plagioclase impregnation. In the distal region, Cr#s start at around an average of 35 and range up to 65 for melt percolated samples. In the medial region, a drop off in Cr# of about 1 Cr# per kilometer is observed with the trend bottoming out at around a Cr# of 10. In the proximal region, Cr#s closer to the medial region are observed as having more fertile values of around 20 but are found amongst melt-impregnated samples with values ranging up to 50. This range is seen as having increasing minimum and maximum values with distance away from the medial section until it reaches its peak at a base Cr# of 30 with a maximum of 65. From this trend, a general model for the secular evolution of the GM mantle section can be established (5). The ridge segment experienced normal mid-oceanic ridge growth with robust mantle melting during the time period represented by the distal region. At the boundary to the medial region, a steep drop-off in melt productivity was experienced, leading to minimal mantle melting during the time period represented by the medial region. Soon thereafter, melting began again, but was trapped in a thickened and cooling lithosphere, causing the melt to pool and react with its host peridotite. (1) Ohara, et al., (2003) G3. 4 (7), 8611, 10.1029/2002GC000469. (2) Dick (1989) Geol Soc. Lond. Spec. Pub. 42:71-105. (3) Ohara, et al., (2009), Eos Trans. AGU, 90(52), Fall Meet. Suppl. Abst.Num. T33D-06 (4) Loocke, et al., (2009), Eos Trans. AGU, 90(52), Fall Meet. Suppl. Abst.Num. T21A-1776 (5) Snow, et al., (2009), Eos Trans. AGU, 90(52), Fall Meet. Suppl. Abst.Num. T33D-07

Reproducibility and reliability of short-TE whole-brain MR spectroscopic imaging of human brain at 3T.

PubMed

Ding, Xiao-Qi; Maudsley, Andrew A; Sabati, Mohammad; Sheriff, Sulaiman; Dellani, Paulo R; Lanfermann, Heinrich

2015-03-01

A feasibility study of an echo-planar spectroscopic imaging (EPSI) using a short echo time (TE) that trades off sensitivity, compared with other short-TE methods, to achieve whole brain coverage using inversion recovery and spatial oversampling to control lipid bleeding. Twenty subjects were scanned to examine intersubject variance. One subject was scanned five times to examine intrasubject reproducibility. Data were analyzed to determine coefficients of variance (COV) and intraclass correlation coefficient (ICC) for N-acetylaspartate (NAA), total creatine (tCr), total choline (tCho), glutamine/glutamate (Glx), and myo-inositol (mI). Regional metabolite concentrations were derived by using multi-voxel analysis based on lobar-level anatomic regions. For whole-brain mean values, the intrasubject COVs were 14%, 15%, and 20% for NAA, tCr, and tCho, respectively, and 31% for Glx and mI. The intersubject COVs were up to 6% higher. For regional distributions, the intrasubject COVs were ≤ 5% for NAA, tCr, and tCho; ≤ 9% for Glx; and ≤15% for mI, with about 6% higher intersubject COVs. The ICCs of 5 metabolites were ≥ 0.7, indicating the reliability of the measurements. The present EPSI method enables estimation of the whole-brain metabolite distributions, including Glx and mI with small voxel size, and a reasonable scan time and reproducibility. © 2014 Wiley Periodicals, Inc.

Radiometric consistency assessment of hyperspectral infrared sounders

NASA Astrophysics Data System (ADS)

Wang, L.; Han, Y.; Jin, X.; Chen, Y.; Tremblay, D. A.

2015-07-01

The radiometric and spectral consistency among the Atmospheric Infrared Sounder (AIRS), the Infrared Atmospheric Sounding Interferometer (IASI), and the Cross-track Infrared Sounder (CrIS) is fundamental for the creation of long-term infrared (IR) hyperspectral radiance benchmark datasets for both inter-calibration and climate-related studies. In this study, the CrIS radiance measurements on Suomi National Polar-orbiting Partnership (SNPP) satellite are directly compared with IASI on MetOp-A and -B at the finest spectral scale and with AIRS on Aqua in 25 selected spectral regions through one year of simultaneous nadir overpass (SNO) observations to evaluate radiometric consistency of these four hyperspectral IR sounders. The spectra from different sounders are paired together through strict spatial and temporal collocation. The uniform scenes are selected by examining the collocated Visible Infrared Imaging Radiometer Suite (VIIRS) pixels. Their brightness temperature (BT) differences are then calculated by converting the spectra onto common spectral grids. The results indicate that CrIS agrees well with IASI on MetOp-A and IASI on MetOp-B at the longwave IR (LWIR) and middle-wave IR (MWIR) bands with 0.1-0.2 K differences. There are no apparent scene-dependent patterns for BT differences between CrIS and IASI for individual spectral channels. CrIS and AIRS are compared at the 25 spectral regions for both Polar and Tropical SNOs. The combined global SNO datasets indicate that, the CrIS-AIRS BT differences are less than or around 0.1 K among 21 of 25 comparison spectral regions and they range from 0.15 to 0.21 K in the remaining 4 spectral regions. CrIS-AIRS BT differences in some comparison spectral regions show weak scene-dependent features.

Radiometric consistency assessment of hyperspectral infrared sounders

NASA Astrophysics Data System (ADS)

Wang, L.; Han, Y.; Jin, X.; Chen, Y.; Tremblay, D. A.

2015-11-01

The radiometric and spectral consistency among the Atmospheric Infrared Sounder (AIRS), the Infrared Atmospheric Sounding Interferometer (IASI), and the Cross-track Infrared Sounder (CrIS) is fundamental for the creation of long-term infrared (IR) hyperspectral radiance benchmark data sets for both intercalibration and climate-related studies. In this study, the CrIS radiance measurements on Suomi National Polar-orbiting Partnership (SNPP) satellite are directly compared with IASI on MetOp-A and MetOp-B at the finest spectral scale and with AIRS on Aqua in 25 selected spectral regions through simultaneous nadir overpass (SNO) observations in 2013, to evaluate radiometric consistency of these four hyperspectral IR sounders. The spectra from different sounders are paired together through strict spatial and temporal collocation. The uniform scenes are selected by examining the collocated Visible Infrared Imaging Radiometer Suite (VIIRS) pixels. Their brightness temperature (BT) differences are then calculated by converting the spectra onto common spectral grids. The results indicate that CrIS agrees well with IASI on MetOp-A and IASI on MetOp-B at the long-wave IR (LWIR) and middle-wave IR (MWIR) bands with 0.1-0.2 K differences. There are no apparent scene-dependent patterns for BT differences between CrIS and IASI for individual spectral channels. CrIS and AIRS are compared at the 25 spectral regions for both polar and tropical SNOs. The combined global SNO data sets indicate that the CrIS-AIRS BT differences are less than or around 0.1 K among 21 of 25 spectral regions and they range from 0.15 to 0.21 K in the remaining four spectral regions. CrIS-AIRS BT differences in some comparison spectral regions show weak scene-dependent features.

Association of CLU and PICALM variants with Alzheimer's disease

PubMed Central

Kamboh, M.I.; Minster, R. L.; Demirci, F.Y.; Ganguli, M.; DeKosky, S.T.; Lopez, O.L.; Barmada, M.M.

2010-01-01

Two recent large genome-wide association studies have reported significant associations in the CLU (APOJ), CR1 and PICALM genes. In order to replicate these findings, we examined 7 single nucleotide polymorphisms (SNPs) most significantly implicated by these studies in a large case-control sample comprising of 2,707 individuals. Principle components analysis revealed no population substructure in our sample. While no association was observed with CR1 SNPs (P=0.30–0.457), a trend of association was seen with the PICALM (P=0.071–0.086) and CLU (P=0.148–0.258) SNPs. A meta-analysis of three studies revealed significant associations with all three genes. Our data from an independent and large case-control sample suggest that these gene regions should be followed up by comprehensive resequencing to find functional variants. PMID:20570404

Genetic analysis of Black Tiger shrimp (Penaeus monodon) across its natural distribution range reveals more recent colonization of Fiji and other South Pacific islands.

PubMed

Waqairatu, Salote S; Dierens, Leanne; Cowley, Jeff A; Dixon, Tom J; Johnson, Karyn N; Barnes, Andrew C; Li, Yutao

2012-08-01

The Black Tiger shrimp (Penaeus monodon) has a natural distribution range from East Africa to the South Pacific Islands. Although previous studies of Indo-Pacific P. monodon have found populations from the Indian Ocean and Australasia to differ genetically, their relatedness to South Pacific shrimp remains unknown. To address this, polymorphisms at eight shared microsatellite loci and haplotypes in a 418-bp mtDNA-CR (control region) sequence were examined across 682 P. monodon from locations spread widely across its natural range, including the South Pacific islands of Fiji, Palau, and Papua New Guinea (PNG). Observed microsatellite heterozygosities of 0.82-0.91, allele richness of 6.85-9.69, and significant mtDNA-CR haplotype variation indicated high levels of genetic diversity among the South Pacific shrimp. Analysis of microsatellite genotypes using a Bayesian STRUCTURE method segregated Indo-Pacific P. monodon into eight distinct clades, with Palau and PNG shrimp clustering among others from Southeast Asia and eastern Australia, respectively, and Fiji shrimp clustering as a distinct group. Phylogenetic analyses of mtDNA-CR haplotypes delineated shrimp into three groupings, with shrimp from Fiji again being distinct by sharing no haplotypes with other populations. Depending on regional location, the genetic structures and substructures identified from the genotyping and mtDNA-CR haplotype phylogeny could be explained by Metapopulation and/or Member-Vagrant type evolutionary processes. Neutrality tests of mutation-drift equilibrium and estimation of the time since population expansion supported a hypothesis that South Pacific P. monodon were colonized from Southeast Asia and eastern Australia during the Pleistocene period over 60,000 years ago when land bridges were more expansive and linked these regions more closely.

Genetic analysis of Black Tiger shrimp (Penaeus monodon) across its natural distribution range reveals more recent colonization of Fiji and other South Pacific islands

PubMed Central

Waqairatu, Salote S; Dierens, Leanne; Cowley, Jeff A; Dixon, Tom J; Johnson, Karyn N; Barnes, Andrew C; Li, Yutao

2012-01-01

The Black Tiger shrimp (Penaeus monodon) has a natural distribution range from East Africa to the South Pacific Islands. Although previous studies of Indo-Pacific P. monodon have found populations from the Indian Ocean and Australasia to differ genetically, their relatedness to South Pacific shrimp remains unknown. To address this, polymorphisms at eight shared microsatellite loci and haplotypes in a 418-bp mtDNA-CR (control region) sequence were examined across 682 P. monodon from locations spread widely across its natural range, including the South Pacific islands of Fiji, Palau, and Papua New Guinea (PNG). Observed microsatellite heterozygosities of 0.82–0.91, allele richness of 6.85–9.69, and significant mtDNA-CR haplotype variation indicated high levels of genetic diversity among the South Pacific shrimp. Analysis of microsatellite genotypes using a Bayesian STRUCTURE method segregated Indo-Pacific P. monodon into eight distinct clades, with Palau and PNG shrimp clustering among others from Southeast Asia and eastern Australia, respectively, and Fiji shrimp clustering as a distinct group. Phylogenetic analyses of mtDNA-CR haplotypes delineated shrimp into three groupings, with shrimp from Fiji again being distinct by sharing no haplotypes with other populations. Depending on regional location, the genetic structures and substructures identified from the genotyping and mtDNA-CR haplotype phylogeny could be explained by Metapopulation and/or Member–Vagrant type evolutionary processes. Neutrality tests of mutation-drift equilibrium and estimation of the time since population expansion supported a hypothesis that South Pacific P. monodon were colonized from Southeast Asia and eastern Australia during the Pleistocene period over 60,000 years ago when land bridges were more expansive and linked these regions more closely. PMID:22957205

Abnormal relationship between GABA, neurophysiology and impulsive behavior in neurofibromatosis type 1.

PubMed

Ribeiro, Maria J; Violante, Inês R; Bernardino, Inês; Edden, Richard A E; Castelo-Branco, Miguel

2015-03-01

Neurofibromatosis type 1 (NF1) is a neurodevelopmental disorder characterized by a broad spectrum of cognitive deficits. In particular, executive dysfunction is recognized as a core deficit of NF1, including impairments in executive attention and inhibitory control. Yet, the neural mechanisms behind these important deficits are still unknown. Here, we studied inhibitory control in a visual go/no-go task in children and adolescents with NF1 and age- and gender-matched controls (n = 16 per group). We applied a multimodal approach using high-density electroencephalography (EEG), to study the evoked brain responses, and magnetic resonance spectroscopy (MRS) to measure the levels of GABA and glutamate + glutamine in the medial frontal cortex, a brain region that plays a pivotal role in inhibitory control, and also in a control region, the occipital cortex. Finally, we run correlation analyses to identify the relationship between inhibitory control, levels of neurotransmitters, and EEG markers of neural function. Individuals with NF1 showed impaired impulse control and reduced EEG correlates of early visual processing (parieto-occipital P1) and inhibitory control (frontal P3). MRS data revealed a reduction in medial frontal GABA+/tCr (total Creatine) levels in the NF1 group, in parallel with the already reported reduced occipital GABA levels. In contrast, glutamate + glutamine/tCr levels were normal, suggesting the existence of abnormal inhibition/excitation balance in this disorder. Notably, medial frontal but not occipital GABA levels correlated with general intellectual abilities (IQ) in NF1, and inhibitory control in both groups. Surprisingly, the relationship between inhibitory control and medial frontal GABA was reversed in NF1: higher GABA was associated with a faster response style whereas in controls it was related to a cautious strategy. Abnormal GABAergic physiology appears, thus, as an important factor underlying impaired cognition in NF1, in a level and region dependent manner. Copyright © 2014 Elsevier Ltd. All rights reserved.

Negative spin Hall magnetoresistance in antiferromagnetic Cr2O3/Ta bilayer at low temperature region

NASA Astrophysics Data System (ADS)

Ji, Yang; Miao, J.; Zhu, Y. M.; Meng, K. K.; Xu, X. G.; Chen, J. K.; Wu, Y.; Jiang, Y.

2018-06-01

We demonstrate the negative spin Hall magnetoresistance (SMR) observed in antiferromagnetic Cr2O3/Ta bilayers at low temperature. The SMR signals are changed from the positive to negative magnitude when monotonously reducing the temperature from 300 K to 50 K. The positive and negative SMR signals are expected to be associated with the two different ways for injection of the spin current, into the boundary ferromagnetic region and the bulk antiferromagnetic region of α-Cr2O3 (0001), respectively. The slopes of the abnormal Hall curves exhibit the same sign with the SMR signal. From the SMR ratio under 3 T, the spin mixing conductance at the Cr2O3/Ta interface is estimated to be 1.12 × 1014 Ω-1.m-2, which is comparable to the one observed in the Y3Fe5O12(YIG)/Pt structure and our early results of the Cr2O3/W structure.

The ZONMET thermodynamic and kinetic model of metal condensation

NASA Astrophysics Data System (ADS)

Petaev, Michail I.; Wood, John A.; Meibom, Anders; Krot, Alexander N.; Keil, Klaus

2003-05-01

The ZONMET model of metal condensation is a FORTRAN computer code that calculates condensation with partial isolation-type equilibrium partitioning of the 19 most abundant elements among 203 gaseous and 488 condensed phases and growth in the nebula of a zoned metal grain by condensation from the nebular gas accompanied by diffusional redistribution of Ni, Co, and Cr. Of five input parameters of the ZONMET model (chemical composition of the system expressed as the dust/gas [ D/ G] ratio, nebular pressure [ Ptot], isolation degree [ξ], cooling rate ( CR), and seed size), only two—the D/ G ratio and the CR of the nebular source region of a zoned Fe,Ni grain—are important in determining the grain radius and Ni, Co, and Cr zoning profiles. We found no evidence for the supercooling during condensation of Fe,Ni metal that is predicted by the homogeneous nucleation theory. The model allows estimates to be made of physicochemical parameters in the CH chondrite nebular source regions. Modeling growth and simultaneous diffusional redistribution of Ni, Co, and Cr in the zoned metal grains of CH chondrites reveals that the condensation zoning profiles were substantially modified by diffusion while the grains were growing in the nebula. This means that previous estimates of the physicochemical conditions in the nebular source regions of CH and CB chondrites, based on measured zoning profiles of Ni, Co, Cr, and platinum group elements in Fe,Ni metal grains, need to be corrected. The two zoned metal grains in the PAT 91456 and NWA 470 CH chondrites studied so far require nebular source regions with different chemical compositions ( D/ G = 1 and D/ G = 4, respectively) and thermal histories characterized by variable cooling rates ( CR = 0.011 + 0.0022 × Δ T K/h and CR = 0.05 + 0.0035 × Δ T K/h, respectively). It appears that the metal grains of the CH chondrites were formed in multiple nebular source regions or in different events within the same source region as the CB chondrite metal grains were formed.

The Microstructural Evolution of Vacuum Brazed 1Cr18Ni9Ti Using Various Filler Metals

PubMed Central

Chen, Yunxia; Cui, Haichao; Lu, Binfeng; Lu, Fenggui

2017-01-01

The microstructures and weldability of a brazed joint of 1Cr18Ni9Ti austenitic stainless steel with BNi-2, BNi82CrSiBFe and BMn50NiCuCrCo filler metals in vacuum were investigated. It can be observed that an interdiffusion region existed between the filler metal and the base metal for the brazed joint of Ni-based filler metals. The width of the interdiffusion region was about 10 μm, and the microstructure of the brazed joint of BNi-2 filler metal was dense and free of obvious defects. In the case of the brazed joint of BMn50NiCuCrCo filler metal, there were pits, pores and crack defects in the brazing joint due to insufficient wettability of the filler metal. Crack defects can also be observed in the brazed joint of BNi82CrSiBFe filler metal. Compared with BMn50NiCuCrCo and BNi82CrSiBFe filler metals, BNi-2 filler metal is the best material for 1Cr18Ni9Ti austenitic stainless steel vacuum brazing because of its distinct weldability. PMID:28772745

Magnetic resonance spectroscopy in mild cognitive impairment: systematic review and meta-analysis.

PubMed

Tumati, Shankar; Martens, Sander; Aleman, André

2013-12-01

Research using proton magnetic resonance spectroscopy (MRS) can potentially elucidate metabolite changes representing early degeneration in Mild Cognitive Impairment (MCI), an early stage of dementia. We integrated the published literature using meta-analysis to identify patterns of metabolite changes in MCI. 29 MRS studies (with a total of 607 MCI patients and 862 healthy controls) were classified according to brain regions. Hedges' g was used as effect size in a random effects model. N-Acetyl Aspartate (NAA) measures were consistently reduced in posterior cingulate (PC), hippocampus, and the paratrigonal white matter (PWM). Creatine (Cr) concentration was reduced in the hippocampus and PWM. Choline (Cho) concentration was reduced in the hippocampus while Cho/Cr ratio was raised in the PC. Myo-inositol (mI) concentration was raised in the PC and mI/Cr ratio was raised in the hippocampus. NAA/mI ratio was reduced in the PC. NAA may be the most reliable marker of brain dysfunction in MCI though mI, Cho, and Cr may also contribute towards this. Copyright © 2013 Elsevier Ltd. All rights reserved.

Novel Rabies Virus-Neutralizing Epitope Recognized by Human Monoclonal Antibody: Fine Mapping and Escape Mutant Analysis†

PubMed Central

Marissen, Wilfred E.; Kramer, R. Arjen; Rice, Amy; Weldon, William C.; Niezgoda, Michael; Faber, Milosz; Slootstra, Jerry W.; Meloen, Rob H.; Clijsters-van der Horst, Marieke; Visser, Therese J.; Jongeneelen, Mandy; Thijsse, Sandra; Throsby, Mark; de Kruif, John; Rupprecht, Charles E.; Dietzschold, Bernhard; Goudsmit, Jaap; Bakker, Alexander B. H.

2005-01-01

Anti-rabies virus immunoglobulin combined with rabies vaccine protects humans from lethal rabies infections. For cost and safety reasons, replacement of the human or equine polyclonal immunoglobulin is advocated, and the use of rabies virus-specific monoclonal antibodies (MAbs) is recommended. We produced two previously described potent rabies virus-neutralizing human MAbs, CR57 and CRJB, in human PER.C6 cells. The two MAbs competed for binding to rabies virus glycoprotein. Using CR57 and a set of 15-mer overlapping peptides covering the glycoprotein ectodomain, a neutralization domain was identified between amino acids (aa) 218 and 240. The minimal binding region was identified as KLCGVL (aa 226 to 231), with key residues K-CGV- identified by alanine replacement scanning. The critical binding region of this novel nonconformational rabies virus epitope is highly conserved within rabies viruses of genotype 1. Subsequently, we generated six rabies virus variants escaping neutralization by CR57 and six variants escaping CRJB. The CR57 escape mutants were only partially covered by CRJB, and all CRJB-resistant variants completely escaped neutralization by CR57. Without exception, the CR57-resistant variants showed a mutation at key residues within the defined minimal binding region, while the CRJB escape viruses showed a single mutation distant from the CR57 epitope (N182D) combined with mutations in the CR57 epitope. The competition between CR57 and CRJB, the in vitro escape profile, and the apparent overlap between the recognized epitopes argues against including both CR57 and CRJB in a MAb cocktail aimed at replacing classical immunoglobulin preparations. PMID:15795253

Effects of Supplemental Chromium Source and Concentration on Growth, Carcass Characteristics, and Serum Lipid Parameters of Broilers Reared Under Normal Conditions.

PubMed

Zheng, Cancai; Huang, Yanling; Xiao, Fang; Lin, Xi; Lloyd, Karen

2016-02-01

An experiment was conducted to investigate the effects of dietary chromium (Cr) source and concentration on growth performance, carcass traits, and some serum lipid parameters of broilers under normal rearing conditions for 42 days. A total of 252 1-day-old Cobb 500 commercial female broilers were randomly allotted by body weight (BW) to one of six replicate cages (six broilers per cage) for each of seven treatments in a completely randomized design involved in a 2 × 3 factorial arrangement of treatments with three Cr sources (Cr propionate (CrPro), Cr picolinate (CrPic), Cr chloride (CrCl3)) and two concentrations of added Cr (0.4 and 2.0 mg of Cr/kg) plus a Cr-unsupplemented control diet. The results showed that dietary Cr supplementation tended to increase the breast muscle percentage compared with the Cr-unsupplemented control group (P = 0.0784), while Cr from CrPic tended to have higher breast muscle percentage compared with Cr from CrCl3 (P = 0.0881). Chromium from CrPic also tended to increase the breast intramuscular fat (IMF) compared with Cr from CrCl3 (P = 0.0648). In addition, supplementation of 0.4 mg/kg Cr tended to decrease low-density lipoprotein cholesterol (LDL-C) (P = 0.0614). Compared with the control group, broilers fed Cr-supplemented diets had higher triglyceride (TG) (P = 0.0129) regardless of Cr source and Cr concentration. Chromium from CrPro and CrPic had lower total cholesterol (TC) compared with Cr from CrCl3 (P = 0.0220). These results indicate that dietary supplementation of Cr has effects on carcass characteristics and serum lipid parameters of broilers under normal rearing conditions, while supplementation of organic Cr can improve carcass characteristics and reduce the cholesterol content in serum.

Evaluation of Renal Blood Flow and Oxygenation in CKD Using Magnetic Resonance Imaging.

PubMed

Khatir, Dinah S; Pedersen, Michael; Jespersen, Bente; Buus, Niels H

2015-09-01

Animal studies suggest that progression of chronic kidney disease (CKD) is related to renal hypoxia. With renal blood supply determining oxygen delivery and sodium absorption being the main contributor to oxygen consumption, we describe the relationship between renal oxygenation, renal artery blood flow, and sodium absorption in patients with CKD and healthy controls. Cross-sectional study. 62 stable patients with CKD stages 3 to 4 (mean age, 61±13 [SD] years) and 24 age- and sex-matched controls. CKD versus control status. Renal artery blood flow, tissue oxygenation (relative changes in deoxyhemoglobin concentration of the renal medulla [MR2*] and cortex [CR2*]), and sodium absorption. Renal artery blood flow was determined by phase-contrast magnetic resonance imaging (MRI); MR2* and CR2* were determined by blood oxygen level-dependent MRI. Ultrafiltered and reabsorbed sodium were determined from measured glomerular filtration rate (mGFR) and 24-hour urine collections. mGFR in patients was 37% that of controls (36±15 vs 97±23 mL/min/1.73 m(2); P < 0.001), and reabsorbed sodium was 37% that of controls (6.9 vs 19.1 mol/24 h; P < 0.001). Single-kidney patient renal artery blood flow was 72% that of controls (319 vs 443 mL/min; P < 0.001). Glomerular filtration fraction was 9% in patients and 18% in controls (P < 0.001). Patients and controls had similar CR2* (13.4 vs 13.3 s(-1)) and medullary MR2* (26.4 vs 26.5 s(-1)) values. Linear regression analysis demonstrated no associations between R2* and renal artery blood flow or sodium absorption. Increasing arterial blood oxygen tension by breathing 100% oxygen had very small effects on CR2*, but reduced MR2* in both groups. Only renal artery blood flow was determined and thus regional perfusion could not be related to CR2* or MR2*. In CKD, reductions of mGFR and reabsorbed sodium are more than double that of renal artery blood flow, whereas cortical and medullary oxygenation are within the range of healthy persons. Reduction in glomerular filtration fraction may prevent renal hypoxia in CKD. Copyright © 2015 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Distinct ontogenic and regional expressions of newly identified Cajal-Retzius cell-specific genes during neocorticogenesis.

PubMed

Yamazaki, Hiroshi; Sekiguchi, Mariko; Takamatsu, Masako; Tanabe, Yasuto; Nakanishi, Shigetada

2004-10-05

Cajal-Retzius (CR) cells are early-generated transient neurons and are important in the regulation of cortical neuronal migration and cortical laminar formation. Molecular entities characterizing the CR cell identity, however, remain largely elusive. We purified mouse cortical CR cells expressing GFP to homogeneity by fluorescence-activated cell sorting and examined a genome-wide expression profile of cortical CR cells at embryonic and postnatal periods. We identified 49 genes that exceeded hybridization signals by >10-fold in CR cells compared with non-CR cells at embryonic day 13.5, postnatal day 2, or both. Among these CR cell-specific genes, 25 genes, including the CR cell marker genes such as the reelin and calretinin genes, are selectively and highly expressed in both embryonic and postnatal CR cells. These genes, which encode generic properties of CR cell specificity, are eminently characterized as modulatory composites of voltage-dependent calcium channels and sets of functionally related cellular components involved in cell migration, adhesion, and neurite extension. Five genes are highly expressed in CR cells at the early embryonic period and are rapidly down-regulated thereafter. Furthermore, some of these genes have been shown to mark two distinctly different focal regions corresponding to the CR cell origins. At the late prenatal and postnatal periods, 19 genes are selectively up-regulated in CR cells. These genes include functional molecules implicated in synaptic transmission and modulation. CR cells thus strikingly change their cellular phenotypes during cortical development and play a pivotal role in both corticogenesis and cortical circuit maturation.

Effects of supplemental nanoparticle trivalent chromium on the nutrient utilization, growth performance and serum traits of broilers.

PubMed

Lin, Y C; Huang, J T; Li, M Z; Cheng, C Y; Lien, T F

2015-02-01

The aim of this study was to investigate the effect of dietary supplementation of nanoparticle trivalent chromium on nutrient utilization, growth performance and serum traits of broilers. This study included two trials. In trial 1, 32 three-week-old broilers were divided into four groups: the control, chromium chloride (CrCl3), chromium picolinate (CrPic) and nanoparticle chromium picolinate (NanoCrPic). Chromium was added at a 1200 μg/kg level to evaluate the nutrient and chromium utilization. In trial 2, 160 one-day-old broilers were randomly divided into four groups as in trial 1, with four replicates. The results of trial 1 indicated that the chromium utilization is as follows: NanoCrPic > CrPic > CrCl3 and control groups, with significant differences between groups (p < 0.05). Crude fat utilization in CrCl3 group was lower than in that the control group (p < 0.05). The results of trial 2 indicated that feed intake of 4-5 weeks showed better result in the CrCl3 group than that in the CrPic group (p < 0.05). The results of serum traits indicated that the LDL-cholesterol in the NanoCrPic groups was lower than that in the CrPic group (p < 0.05). The NanoCrpic and CrPic groups showed significantly increased serum chromium concentration when compared with the control and CrCl3 groups; the triglyceride level in the CrCl3 group was lower than that in the CrPic group (p < 0.05). This study concluded that compared with CrPic, NanoCrpic supplementation could increase chromium utilization and lower the serum LDL-cholesterol of broilers. Journal of Animal Physiology and Animal Nutrition © 2014 Blackwell Verlag GmbH.

Caloric restriction counteracts age-related changes in the activities of sorbitol metabolizing enzymes from mouse liver

PubMed Central

Hagopian, Kevork; Ramsey, Jon J.; Weindruch, Richard

2009-01-01

The influence of caloric restriction (CR) on hepatic sorbitol-metabolizing enzyme activities was investigated in young and old mice. Aldose reductase and sorbitol dehydrogenase activities were significantly lower in old CR mice than in old controls. Young CR mice showed decreased aldose reductase activity and a trend towards decreased sorbitol dehydrogenase when compared to controls. Metabolites of the pathway, namely sorbitol, glucose and fructose were decreased by CR in young and old mice. Pyruvate levels were decreased by CR in both young and old mice, while lactate decreased only in old CR. Malate levels increased in old CR but remained unchanged in young CR, when compared with controls. Accordingly, the lactae/pyruvate and malate/pyruvate ratios in young and old CR mice were increased, indicating increased NADH/NAD and NADPH/NADP redox couples, respectively. The results indicate that decreased glucose levels under CR conditions lead to decreased sorbitol pathway enzyme activities and metabolite levels, and could contribute to the beneficial effects of long-term CR through decreased sorbitol levels and NADPH sparing. PMID:18953666

Hair chromium as an index of chromium exposure of tannery workers.

PubMed Central

Randall, J A; Gibson, R S

1989-01-01

The use of hair chromium (Cr) concentrations as an index of Cr exposure of tannery workers was investigated. As has been shown earlier, Cr from Cr III compounds used in the leather tanning industry is absorbed because concentrations of Cr in serum and urine of tannery workers are significantly increased compared with corresponding concentrations for unexposed controls. Hair samples were collected from 71 male tannery workers from four southern Ontario tanneries and from 53 male controls not exposed to Cr in the workplace. Subjects were matched for age, race, and socioeconomic status. Hair samples were washed, ashed in a low temperature asher, and analysed by flameless atomic absorption. The median hair Cr concentrations for the tannery workers (551 ng/g) was significantly higher (p = 0.0001) than for the controls (123 ng/g). For the tannery workers, hair Cr concentrations were positively and significantly correlated with serum Cr (r = 0.52, p less than 0.01) and with the preshift and postshift urinary Cr/creatinine ratios (r = 0.43, p less than 0.01; r = 0.64, p less than 0.01, respectively). These data indicate that trivalent Cr absorbed from leather tanning compounds results in raised concentrations of Cr in hair and that hair Cr concentrations may be used as an index of industrial Cr exposure. PMID:2930727

Resting-state global functional connectivity as a biomarker of cognitive reserve in mild cognitive impairment.

PubMed

Franzmeier, N; Caballero, M Á Araque; Taylor, A N W; Simon-Vermot, L; Buerger, K; Ertl-Wagner, B; Mueller, C; Catak, C; Janowitz, D; Baykara, E; Gesierich, B; Duering, M; Ewers, M

2017-04-01

Cognitive reserve (CR) shows protective effects in Alzheimer's disease (AD) and reduces the risk of dementia. Despite the clinical significance of CR, a clinically useful diagnostic biomarker of brain changes underlying CR in AD is not available yet. Our aim was to develop a fully-automated approach applied to fMRI to produce a biomarker associated with CR in subjects at increased risk of AD. We computed resting-state global functional connectivity (GFC), i.e. the average connectivity strength, for each voxel within the cognitive control network, which may sustain CR due to its central role in higher cognitive function. In a training sample including 43 mild cognitive impairment (MCI) subjects and 24 healthy controls (HC), we found that MCI subjects with high CR (> median of years of education, CR+) showed increased frequency of high GFC values compared to MCI-CR- and HC. A summary index capturing such a surplus frequency of high GFC was computed (called GFC reserve (GFC-R) index). GFC-R discriminated MCI-CR+ vs. MCI-CR-, with the area under the ROC = 0.84. Cross-validation in an independently recruited test sample of 23 MCI subjects showed that higher levels of the GFC-R index predicted higher years of education and an alternative questionnaire-based proxy of CR, controlled for memory performance, gray matter of the cognitive control network, white matter hyperintensities, age, and gender. In conclusion, the GFC-R index that captures GFC changes within the cognitive control network provides a biomarker candidate of functional brain changes of CR in patients at increased risk of AD.

Chromium oxide as a metal diffusion barrier layer: An x-ray absorption fine structure spectroscopy study

NASA Astrophysics Data System (ADS)

Ahamad Mohiddon, Md.; Lakshun Naidu, K.; Ghanashyam Krishna, M.; Dalba, G.; Ahmed, S. I.; Rocca, F.

2014-01-01

The interaction at the interface between chromium and amorphous Silicon (a-Si) films in the presence of a sandwich layer of chromium oxide is investigated using X-ray absorption fine structure (XAFS) spectroscopy. The oxidized interface was created, in situ, prior to the deposition of a 400 nm tick a-Si layer over a 50 nm tick Cr layer. The entire stack of substrate/metallic Cr/Cr2O3/a-Si was then annealed at temperatures from 300 up to 700 °C. Analysis of the near edge and extended regions of each XAFS spectrum shows that only a small fraction of Cr is able to diffuse through the oxide layer up to 500 °C, while the remaining fraction is buried under the oxide layer in the form of metallic Cr. At higher temperatures, diffusion through the oxide layer is enhanced and the diffused metallic Cr reacts with a-Si to form CrSi2. At 700 °C, the film contains Cr2O3 and CrSi2 without evidence of unreacted metallic Cr. The activation energy and diffusion coefficient of Cr are quantitatively determined in the two temperature regions, one where the oxide acts as diffusion barrier and another where it is transparent to Cr diffusion. It is thus demonstrated that chromium oxide can be used as a diffusion barrier to prevent metal diffusion into a-Si.

Clinical studies on chromium picolinate supplementation in diabetes mellitus--a review.

PubMed

Broadhurst, C Leigh; Domenico, Philip

2006-12-01

Chromium (Cr) picolinate (CrPic) is a widely used nutritional supplement for optimal insulin function. A relationship among Cr status, diabetes, and associated pathologies has been established. Virtually all trials using CrPic supplementation for subjects with diabetes have demonstrated beneficial effects. Thirteen of 15 clinical studies (including 11 randomized, controlled studies) involving a total of 1,690 subjects (1,505 in CrPic group) reported significant improvement in at least one outcome of glycemic control. All 15 studies showed salutary effects in at least one parameter of diabetes management, including dyslipidemia. Positive outcomes from CrPic supplementation included reduced blood glucose, insulin, cholesterol, and triglyceride levels and reduced requirements for hypoglycemic medication. The greater bioavailability of CrPic compared with other forms of Cr (e.g., niacin-bound Cr or CrCl(3)) may explain its comparatively superior efficacy in glycemic and lipidemic control. The pooled data from studies using CrPic supplementation for type 2 diabetes mellitus subjects show substantial reductions in hyperglycemia and hyperinsulinemia, which equate to a reduced risk for disease complications. Collectively, the data support the safety and therapeutic value of CrPic for the management of cholesterolemia and hyperglycemia in subjects with diabetes.

Control of Surface Segregation in Bimetallic NiCr Nanoalloys Immersed in Ag Matrix

PubMed Central

Bohra, Murtaza; Singh, Vidyadhar; Grammatikopoulos, Panagiotis; Toulkeridou, Evropi; Diaz, Rosa E.; Bobo, Jean-François; Sowwan, Mukhles

2016-01-01

Cr-surface segregation is a main roadblock encumbering many magneto-biomedical applications of bimetallic M-Cr nanoalloys (where M = Fe, Co and Ni). To overcome this problem, we developed Ni95Cr5:Ag nanocomposite as a model system, consisting of non-interacting Ni95Cr5 nanoalloys (5 ± 1 nm) immersed in non-magnetic Ag matrix by controlled simultaneous co-sputtering of Ni95Cr5 and Ag. We employed Curie temperature (TC) as an indicator of phase purity check of these nanocomposites, which is estimated to be around the bulk Ni95Cr5 value of 320 K. This confirms prevention of Cr-segregation and also entails effective control of surface oxidation. Compared to Cr-segregated Ni95Cr5 nanoalloy films and nanoclusters, we did not observe any unwanted magnetic effects such as presence Cr-antiferromagnetic transition, large non-saturation, exchange bias behavior (if any) or uncompensated higher TC values. These nanocomposites films also lose their unique magnetic properties only at elevated temperatures beyond application requirements (≥800 K), either by showing Ni-type behavior or by a complete conversion into Ni/Cr-oxides in vacuum and air environment, respectively. PMID:26750659

Occupational exposure to Cr(VI): comparison between chromium levels in lymphocytes, erythrocytes, and urine.

PubMed

Lukanova, A; Toniolo, P; Zhitkovich, A; Nikolova, V; Panev, T; Popov, T; Taioli, E; Costa, M

1996-01-01

The relationships between chromium (Cr) levels in lymphocytes, erythrocytes, urine, and ambient air were compared among 14 chrome-platers from a metallurgic plant in Bulgaria and two groups of local controls, one from the same heavily polluted industrial town as the chrome-platers (n = 11) and one from a seaside resort town 100 km away (n = 6). Among the chrome-platers, the Cr concentration in peripheral lymphocytes was positively correlated with total Cr and Cr(VI) levels in ambient air and with Cr excretion in urine. As compared to the controls, the chrome-platers had mean Cr levels in lymphocytes twice as high, in erythrocytes ninefold higher, and in urine fourfold to eightfold higher. Although Cr levels in urine and lymphocytes were similar between the two control groups, levels in erythrocytes were 3 times higher among subjects from the industrial area than among those from the seaside town. The study suggests that lymphocyte Cr could be a good indicator of the Cr body burden caused by high exposures to Cr(VI), such as in electroplating operations. In these conditions, erythrocyte Cr may be less useful, possibly owing to increased toxicity due to the high affinity of erythrocytes for Cr. However, when exposure is lower, such as in most environmental situations, erythrocyte Cr should provide a better and more sensitive index than lymphocyte Cr. By contrast, urinary Cr, which provides information on total Cr exposure, including Cr(III) from dietary and environmental sources, does not seem to be of value for studying occupational exposure to Cr(VI).

Dorsolateral prefrontal cortex N-acetylaspartate/total creatine (NAA/tCr) loss in male recreational cannabis users.

PubMed

Hermann, Derik; Sartorius, Alexander; Welzel, Helga; Walter, Sigrid; Skopp, Gisela; Ende, Gabriele; Mann, Karl

2007-06-01

Cannabinoids present neurotoxic and neuroprotective properties in in vitro studies, inconsistent alterations in human neuroimaging studies, neuropsychological deficits, and an increased risk for psychotic episodes. Proton magnetic resonance spectroscopy ((1)H-MRS), neuropsychological testing, and hair analysis for cannabinoids was performed in 13 male nontreatment-seeking recreational cannabis users and 13 male control subjects. A significantly diminished N-acetylaspartate/total creatine (NAA/tCr) ratio in the dorsolateral prefrontal cortex (DLPFC) was observed in cannabis users (p = .0003). The NAA/tCr in the putamen/globus pallidum region correlated significantly with cannabidiol (R(2) = .66, p = .004). Results of the Wisconsin Card Sorting test, Trail making Test, and D2 test for attention were influenced by cannabinoids. Chronic recreational cannabis use is associated with an indication of diminished neuronal and axonal integrity in the DLPFC in this study. As chronic cannabis use is a risk factor for psychosis, these results are interesting because diminished NAA/tCr ratios in the DLPFC and neuropsychological deficits were also reported in schizophrenia. The strong positive correlation of NAA/tCr and cannabidiol in the putamen/globus pallidum is in line with neuroprotective properties of cannabidiol, which were also observed in in vitro model studies of Parkinson's disease.

Atmosphere

NASA Astrophysics Data System (ADS)

Ghosh, D.; Mitra, S. K.

2014-05-01

This paper investigates the high-temperature corrosion behavior of microstructurally different regions of the weldment of 9 Cr-1 Mo steel used in thermal power plant boiler in SO2 + O2 environment. The weldment is produced by tungsten inert gas welding method, and the different regions of the weldment (weld metal, heat-affected zone, and base metal) are exposed in SO2 + O2 (ratio 2:1) environment at 973 K for 120 h. The reaction kinetics and corrosion growth rate of different regions of weldment in isothermal condition are evaluated. The post corroded scales of the different specimens are studied in SEM, EDS, and XRD. The results indicate that the weld metal shows higher corrosion rate followed by HAZ and base metal. The higher rate of corrosion of weldmetal is mainly attributed to the least protective inner scale of Cr2O3 with minimum Cr Content. This is due to the formation of delta ferrite, which leads to the precipitation of the Cr-based secondary phases and depletes the free Cr from the matrix. The thermal cycles during welding at high temperature are favorable for the formation of delta ferrite. On the other hand, in absence of delta ferrite, the base metal and HAZ regions of the weldment show lower corrosion rate than weld metal. The difference in corrosion rate in the three regions of the weldment is supplemented by post-corroded scale characterizations.

Interstitial loop transformations in FeCr

DOE PAGES

Béland, Laurent Karim; Osetsky, Yuri N.; Stoller, Roger E.; ...

2015-03-27

Here, we improve the Self-Evolving Atomistic Kinetic Monte Carlo (SEAKMC) algorithm by integrating the Activation Relaxation Technique nouveau (ARTn), a powerful open-ended saddle-point search method, into the algorithm. We use it to investigate the reaction of 37-interstitial 1/2[1 1 1] and 1/2[View the MathML source] loops in FeCr at 10 at.% Cr. They transform into 1/2[1 1 1], 1/2[View the MathML source], [1 0 0] and [0 1 0] 74-interstitial clusters with an overall barrier of 0.85 eV. We find that Cr decoration locally inhibits the rotation of crowdions, which dictates the final loop orientation. Moreover, the final loop orientationmore » depends on the details of the Cr decoration. Generally, a region of a given orientation is favored if Cr near its interface with a region of another orientation is able to inhibit reorientation at this interface more than the Cr present at the other interfaces. Also, we find that substitutional Cr atoms can diffuse from energetically unfavorable to energetically favorable sites within the interlocked 37-interstitial loops conformation with barriers of less than 0.35 eV.« less

Capacity and equity in cardiac rehabilitation in the eastern region: good and bad news.

PubMed

Jennings, S; Carey, D

2004-01-01

To document current baseline eligibility for Phase 3 cardiac rehabilitation (CR) and the capacity to meet this need in hospitals in the Eastern Regional Health Authority. Information on the eligible population and the capacity for CR was collected in all nine hospitals retrospectively (February-March 2001). Forty-seven per cent of eligible patients were invited to participate with only two-thirds attending. Completion rates were very high (89%) in attenders. Age and health board area were significant independent predictors of being invited to CR. Gender was not independent of age. Fifty-three per cent of the need for this service was met by capacity in the region's nine hospitals in 2000 rising to 59% in 2002. Many eligible patients are not invited to CR. Lack of capacity is a problem. Among the invited, non-participation is a factor. Inequity in age and inter-hospital variation in invitation is noted.

75 FR 59687 - Proposed Information Collection; Comment Request; Alaska Region Bering Sea & Aleutian Islands...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-28

... among harvesters, processors, and coastal communities and monitors the ``economic stability for... Collection; Comment Request; Alaska Region Bering Sea & Aleutian Islands (BSAI) Crab Economic Data Reports... CR Program's mandatory economic data collection report (EDR) used to assess the efficacy of the CR...

Fast quantification of proton magnetic resonance spectroscopic imaging with artificial neural networks

NASA Astrophysics Data System (ADS)

Bhat, Himanshu; Sajja, Balasrinivasa Rao; Narayana, Ponnada A.

2006-11-01

Accurate quantification of the MRSI-observed regional distribution of metabolites involves relatively long processing times. This is particularly true in dealing with large amount of data that is typically acquired in multi-center clinical studies. To significantly shorten the processing time, an artificial neural network (ANN)-based approach was explored for quantifying the phase corrected (as opposed to magnitude) spectra. Specifically, in these studies radial basis function neural network (RBFNN) was used. This method was tested on simulated and normal human brain data acquired at 3T. The N-acetyl aspartate (NAA)/creatine (Cr), choline (Cho)/Cr, glutamate + glutamine (Glx)/Cr, and myo-inositol (mI)/Cr ratios in normal subjects were compared with the line fitting (LF) technique and jMRUI-AMARES analysis, and published values. The average NAA/Cr, Cho/Cr, Glx/Cr and mI/Cr ratios in normal controls were found to be 1.58 ± 0.13, 0.9 ± 0.08, 0.7 ± 0.17 and 0.42 ± 0.07, respectively. The corresponding ratios using the LF and jMRUI-AMARES methods were 1.6 ± 0.11, 0.95 ± 0.08, 0.78 ± 0.18, 0.49 ± 0.1 and 1.61 ± 0.15, 0.78 ± 0.07, 0.61 ± 0.18, 0.42 ± 0.13, respectively. These results agree with those published in literature. Bland-Altman analysis indicated an excellent agreement and minimal bias between the results obtained with RBFNN and other methods. The computational time for the current method was 15 s compared to approximately 10 min for the LF-based analysis.

Maturation of limbic regions in Asperger syndrome: a preliminary study using proton magnetic resonance spectroscopy and structural magnetic resonance imaging.

PubMed

O'Brien, Finian M; Page, Lisa; O'Gorman, Ruth L; Bolton, Patrick; Sharma, Ajay; Baird, Gillian; Daly, Eileen; Hallahan, Brian; Conroy, Ronán M; Foy, Catherine; Curran, Sarah; Robertson, Dene; Murphy, Kieran C; Murphy, Declan G M

2010-11-30

People with autistic spectrum disorders (ASD, including Asperger syndrome) may have developmental abnormalities in the amygdala-hippocampal complex (AHC). However, in vivo, age-related comparisons of both volume and neuronal integrity of the AHC have not yet been carried out in people with Asperger syndrome (AS) versus controls. We compared structure and metabolic activity of the right AHC of 22 individuals with AS and 22 healthy controls aged 10-50 years and examined the effects of age between groups. We used structural magnetic resonance imaging (sMRI) to measure the volume of the AHC, and magnetic resonance spectroscopy ((1)H-MRS) to measure concentrations of N-acetyl aspartate (NAA), creatine+phosphocreatine (Cr+PCr), myo-inositol (mI) and choline (Cho). The bulk volume of the amygdala and the hippocampus did not differ significantly between groups, but there was a significant difference in the effect of age on the hippocampus in controls. Compared with controls, young (but not older) people with AS had a significantly higher AHC concentration of NAA and a significantly higher NAA/Cr ratio. People with AS, but not controls, had a significant age-related reduction in NAA and the NAA/Cr ratio. Also, in people with AS, but not controls, there was a significant relationship between concentrations of choline and age so that choline concentrations reduced with age. We therefore suggest that people with AS have significant differences in neuronal and lipid membrane integrity and maturation of the AHC. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Chromium Supplementation Improves Glucose Tolerance in Diabetic Goto-Kakizaki Rats

PubMed Central

Abdourahman, Aicha; Edwards, John G.

2016-01-01

Summary Chromium supplementation (Cr) may be useful in the management of diabetes and appears to improve some aspects of glucose handling. However, several studies have used either high doses of Cr supplementation or have placed control animals on a Cr-deficient diet. We therefore wanted to test whether Cr dosages in the ranges that more closely approximate recommended levels of supplementation in humans are efficacious in glycemic control under normal dietary conditions. Euglycemic Wistar or diabetic Goto-Kakizaki (GK) rats (a model of nonobese NIDDM) were assigned to water (control) or chromium picolinate (Cr-P) supplementation (1 or 10 mg/kg/day) groups for up to 32 weeks. Glucose tolerance was tested following an overnight fast by injecting sterile glucose (1.0 g/kg, i.p.) and then measuring blood glucose at select times to determine the sensitivity to glucose by calculation of the area under the curve. Cr-P did not significantly alter the growth of the animals. In the euglycemic Wistar rats, Cr-P supplementation did not alter the response to a glucose tolerance test. In the GK rats, Cr-P supplementation significantly improved glucose tolerance at both levels of Cr-P supplementation (1 mg/kg/day: H20; 100 ± 11%; Cr-P 70 6 8%; 10 mg/kg/day: H20; 100 ± 10%; Cr-P 66 ± 9 %). Cr-P supplementation produced a small improvement in some indices of glycemic control. There were no differences observed for the two levels of Cr-P supplementation suggested that we did not identify a threshold for Cr-P effects, and future studies may use lower doses to find a threshold effect for improving glucose tolerance in diabetics. PMID:18629917

The human serotonin 5-HT{sub 2C} receptor: Complete cDNA, genomic structure, and alternatively spliced variant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xie, Enzhong; Zhu, Lingyu; Zhao, Lingyun

1996-08-01

The complete 4775-nt cDNA encoding the human serotonin 5-HT{sub 2C} receptor (5-HT{sub 2C}R), a G-protein-coupled receptor, has been isolated. It contains a 1377-nt coding region flanked by a 728-nt 5{prime}-untranslated region and a 2670-nt 3{prime}-untranslated region. By using the cloned 5-HT{sub 2C}R cDNA probe, the complete human gene for this receptor has been isolated and shown to contain six exons and five introns spanning at least 230 kb of DNA. The coding region of the human 5-HT{sub 2C}R gene is interrupted by three introns, and the positions of the intron/exon junctions are conserved between the human and the rodent genes.more » In addition, an alternatively spliced 5-HT{sub 2C}R RNA that contains a 95-nt deletion in the region coding for the second intracellular loop and the fourth transmembrane domain of the receptor has been identified. This deletion leads to a frameshift and premature termination so that the short isoform RNA encodes a putative protein of 248 amino acids. The ratio for the short isoform over the 5-HT{sub 2C}R RNA was found to be higher in choroid plexus tumor than in normal brain tissue, suggesting the possibility of differential regulation of the 5-HT{sub 2C}R gene in different neural tissues or during tumorigenesis. Transcription of the human 5-HT{sub 2C}R gene was found to be initiated at multiple sites. No classical TATA-box sequence was found at the appropriate location, and the 5{prime}-flanking sequence contains many potential transcription factor-binding sites. A 7.3-kb 5{prime}-flanking 5-HT{sub 2C}R DNA directed the efficient expression of a luciferase reported gene in SK-N-SH and IMR32 neuroblastoma cells, indicating that is contains a functional promoter. 69 refs., 8 figs., 1 tab.« less

Identifications of captive and wild tilapia species existing in Hawaii by mitochondrial DNA control region sequence.

PubMed

Wu, Liang; Yang, Jinzeng

2012-01-01

The tilapia family of the Cichlidae includes many fish species, which live in freshwater and saltwater environments. Several species, such as O. niloticus, O. aureus, and O. mossambicus, are excellent for aquaculture because these fish are easily reproduced and readily adapt to diverse environments. Historically, tilapia species, including O. mossambicus, S. melanotheron, and O. aureus, were introduced to Hawaii many decades ago, and the state of Hawaii uses the import permit policy to prevent O. niloticus from coming into the islands. However, hybrids produced from O. niloticus may already be present in the freshwater and marine environments of the islands. The purpose of this study was to identify tilapia species that exist in Hawaii using mitochondrial DNA analysis. In this study, we analyzed 382 samples collected from 13 farm (captive) and wild tilapia populations in Oahu and the Hawaii Islands. Comparison of intraspecies variation between the mitochondrial DNA control region (mtDNA CR) and cytochrome c oxidase I (COI) gene from five populations indicated that mtDNA CR had higher nucleotide diversity than COI. A phylogenetic tree of all sampled tilapia was generated using mtDNA CR sequences. The neighbor-joining tree analysis identified seven distinctive tilapia species: O. aureus, O. mossambicus, O. niloticus, S. melanotheron, O. urolepies, T. redalli, and a hybrid of O. massambicus and O. niloticus. Of all the populations examined, 10 populations consisting of O. aureus, O. mossambicus, O. urolepis, and O. niloticus from the farmed sites were relatively pure, whereas three wild populations showed some degree of introgression and hybridization. This DNA-based tilapia species identification is the first report that confirmed tilapia species identities in the wild and captive populations in Hawaii. The DNA sequence comparisons of mtDNA CR appear to be a valid method for tilapia species identification. The suspected tilapia hybrids that consist of O. niloticus are present in captive and wild populations in Hawaii.

Identifications of Captive and Wild Tilapia Species Existing in Hawaii by Mitochondrial DNA Control Region Sequence

PubMed Central

Wu, Liang; Yang, Jinzeng

2012-01-01

Background The tilapia family of the Cichlidae includes many fish species, which live in freshwater and saltwater environments. Several species, such as O. niloticus, O. aureus, and O. mossambicus, are excellent for aquaculture because these fish are easily reproduced and readily adapt to diverse environments. Historically, tilapia species, including O. mossambicus, S. melanotheron, and O. aureus, were introduced to Hawaii many decades ago, and the state of Hawaii uses the import permit policy to prevent O. niloticus from coming into the islands. However, hybrids produced from O. niloticus may already be present in the freshwater and marine environments of the islands. The purpose of this study was to identify tilapia species that exist in Hawaii using mitochondrial DNA analysis. Methodology/Principal Findings In this study, we analyzed 382 samples collected from 13 farm (captive) and wild tilapia populations in Oahu and the Hawaii Islands. Comparison of intraspecies variation between the mitochondrial DNA control region (mtDNA CR) and cytochrome c oxidase I (COI) gene from five populations indicated that mtDNA CR had higher nucleotide diversity than COI. A phylogenetic tree of all sampled tilapia was generated using mtDNA CR sequences. The neighbor-joining tree analysis identified seven distinctive tilapia species: O. aureus, O. mossambicus, O. niloticus, S. melanotheron, O. urolepies, T. redalli, and a hybrid of O. massambicus and O. niloticus. Of all the populations examined, 10 populations consisting of O. aureus, O. mossambicus, O. urolepis, and O. niloticus from the farmed sites were relatively pure, whereas three wild populations showed some degree of introgression and hybridization. Conclusions/Significance This DNA-based tilapia species identification is the first report that confirmed tilapia species identities in the wild and captive populations in Hawaii. The DNA sequence comparisons of mtDNA CR appear to be a valid method for tilapia species identification. The suspected tilapia hybrids that consist of O. niloticus are present in captive and wild populations in Hawaii. PMID:23251613

Review of Ice-Control Methods at Lock 8, Welland Canal, Port Colborne, Ontario

DTIC Science & Technology

2016-05-01

ER D C/ CR RE L SR -1 6- 1 Review of Ice-Control Methods at Lock 8, Welland Canal, Port Colborne, Ontario Co ld R eg io ns R es ea rc... Lock 8, Welland Canal, Port Colborne, Ontario Robert B. Haehnel U.S. Army Engineer Research and Development Center (ERDC) Cold Regions Research and...CRREL and the St. Lawrence Seaway Management Corporation C-15-CRL-15, “ Lock 8 Ice Management Study, Lake Erie Port Colborne, Ontario, Canada

Chromium(III) release from chromium-tanned leather elicits allergic contact dermatitis: a use test study.

PubMed

Hedberg, Yolanda S; Erfani, Behnaz; Matura, Mihály; Lidén, Carola

2018-05-01

Chromium (Cr) is a common skin sensitizer. The use of Cr(VI) in leather is restricted in the EU, but that of Cr(III) is not. To assess whether prolonged exposure to Cr-tanned leather with mainly Cr(III) release may elicit allergic contact dermatitis in Cr-allergic individuals. Ten Cr-allergic subjects and 22 controls were patch tested with serial dilutions of Cr(III) and Cr(VI), and with leather samples. They then conducted a use test with a Cr-tanned and a Cr-free leather bracelet over a period of 3 weeks, for 12 h per day. Cr deposited on the skin from the bracelets was measured in the controls, and the diphenylcarbazide test for Cr(VI) and extraction tests for Cr(III) and Cr(VI) were conducted for the different leathers. Four of 10 Cr-allergic subjects developed positive reactions to the Cr-tanned bracelet within 7-21 days, whereas only 1 of 10 had a positive patch test reaction to this leather. Cr released from the Cr-tanned leather was most probably entirely Cr(III), with a quantifiable amount being deposited on the skin. This study strongly suggests that prolonged and repeated exposure to Cr-tanned leather with mainly Cr(III) release is capable of eliciting allergic contact dermatitis in Cr-allergic individuals. © 2018 The Authors. Contact Dermatitis published by John Wiley & Sons Ltd.

GABA and Glutamate in Children with Primary Complex Motor Stereotypies: A 1H MRS Study at 7T

PubMed Central

Harris, A. D.; Singer, H. S.; Horska, A.; Kline, T.; Ryan, M.; Edden, R. A. E.; Mahone, E. Mark

2015-01-01

Background and Purpose Complex motor stereotypies (CMS) are rhythmic, repetitive, fixed, purposeful but purposeless movements that stop with distraction. They can occur in otherwise normal healthy children (primary stereotypies), as well in those with autism spectrum disorders (secondary stereotypies). The underlying neurobiological basis for these movements is unknown, but thought to involve cortical-striatal-thalamo-cortical pathways. In order to further clarify potential neurochemical alterations, GABA, glutamate (Glu), glutamine (Gln), N-acetyl aspartate (NAA) and choline (Cho) levels were measured in four frontostriatal regions, using 1H MRS at 7T. Materials and Methods A total of 18 children with primary CMS and 24 typically developing controls, ages 5-10 years completed MRS at 7T. Single voxel STEAM acquisitions from the anterior cingulate cortex (ACC), premotor cortex (PMC), dorsolateral prefrontal cortex (DLPFC) and striatum were obtained and metabolites were quantified with respect to creatine using LCModel. Results The 7T scan was well tolerated by all participants. Compared to controls, children with CMS had lower levels of GABA ACC (GABA/Cr, p=0.049; GABA/Glu: p=0.051) and striatum (GABA/Cr: p= 0.028; GABA/Glu: p=0.0037), but not the DLPFC or PMC. Glu, Gln, NAA, and Cho levels did not differ between groups in any of the aforementioned regions. Within the CMS group, reduced GABA/Cr in the ACC was significantly associated with greater severity of motor stereotypies (r=-0.59, p= 0.021). Conclusions These results suggest possible GABAergic dysfunction within corticostriatal pathways in children with primary CMS. PMID:26542237

Femtosecond Cr:LiSAF and Cr:LiCAF lasers pumped by tapered diode lasers.

PubMed

Demirbas, Umit; Schmalz, Michael; Sumpf, Bernd; Erbert, Götz; Petrich, Gale S; Kolodziejski, Leslie A; Fujimoto, James G; Kärtner, Franz X; Leitenstorfer, Alfred

2011-10-10

We report compact, low-cost and efficient Cr:Colquiriite lasers that are pumped by high brightness tapered laser diodes. The tapered laser diodes provided 1 to 1.2 W of output power around 675 nm, at an electrical-to-optical conversion efficiency of about 30%. Using a single tapered diode laser as the pump source, we have demonstrated output powers of 500 mW and 410 mW together with slope efficiencies of 47% and 41% from continuous wave (cw) Cr:LiSAF and Cr:LiCAF lasers, respectively. In cw mode-locked operation, sub-100-fs pulse trains with average power between 200 mW and 250 mW were obtained at repetition rates around 100 MHz. Upon pumping the Cr:Colquiriite lasers with two tapered laser diodes (one from each side of the crystal), we have observed scaling of cw powers to 850 mW in Cr:LiSAF and to 650 mW in Cr:LiCAF. From the double side pumped Cr:LiCAF laser, we have also obtained ~220 fs long pulses with 5.4 nJ of pulse energy at 77 MHz repetition rate. These are the highest energy levels reported from Cr:Colquiriite so far at these repetition rates. Our findings indicate that tapered diodes in the red spectral region are likely to become the standard pump source for Cr:Colquiriite lasers in the near future. Moreover, the simplified pumping scheme might facilitate efficient commercialization of Cr:Colquiriite systems, bearing the potential to significantly boost applications of cw and femtosecond lasers in this spectral region (750-1000 nm).

Mitochondrial Haplogroup T Is Associated with Obesity in Austrian Juveniles and Adults

PubMed Central

Ebner, Sabine; Mangge, Harald; Langhof, Helmut; Halle, Martin; Siegrist, Monika; Aigner, Elmar; Paulmichl, Katharina; Paulweber, Bernhard; Datz, Christian; Sperl, Wolfgang; Kofler, Barbara; Weghuber, Daniel

2015-01-01

Background Recent publications have reported contradictory data regarding mitochondrial DNA (mtDNA) variation and its association with body mass index. The aim of the present study was to compare the frequencies of mtDNA haplogroups as well as control region (CR) polymorphisms of obese juveniles (n = 248) and obese adults (n = 1003) versus normal weight controls (njuvenile = 266, nadults = 595) in a well-defined, ethnically homogenous, age-matched comparative cohort of Austrian Caucasians. Methodology and Principal Findings Using SNP analysis and DNA sequencing, we identified the nine major European mitochondrial haplogroups and CR polymorphisms. Of these, only the T haplogroup frequency was increased in the juvenile obese cohort versus the control subjects [11.7% in obese vs. 6.4% in controls], although statistical significance was lost after adjustment for sex and age. Similar data were observed in a local adult cohort, in which haplogroup T was found at a significantly higher frequency in the overweight and obese subjects than in the normal weight group [9.7% vs. 6.2%, p = 0.012, adjusted for sex and age]. When all obese subjects were considered together, the difference in the frequency of haplogroup T was even more clearly seen [10.1% vs. 6.3%, p = 0.002, OR (95% CI) 1.71 (1.2–2.4), adjusted for sex and age]. The frequencies of the T haplogroup-linked CR polymorphisms C16294T and the C16296T were found to be elevated in both the juvenile and the adult obese cohort compared to the controls. Nevertheless, no mtDNA haplogroup or CR polymorphism was robustly associated with any of several investigated metabolic and cardiovascular parameters (e.g., blood pressure, blood glucose concentration, triglycerides, cholesterol) in all obese subjects. Conclusions and Significance By investigation of this large ethnically and geographically homogenous cohort of Middle European Caucasians, only mtDNA haplogroup T was identified as an obesity risk factor. PMID:26322975

Calorie restriction and bone health in young, overweight individuals.

PubMed

Redman, Leanne M; Rood, Jennifer; Anton, Stephen D; Champagne, Catherine; Smith, Steven R; Ravussin, Eric

2008-09-22

Calorie restriction (CR) is promoted to increase longevity, yet this regimen could lead to bone loss and fracture and therefore affect quality of life. Forty-six individuals were randomized to 4 groups for 6 months: (1) healthy diet (control group); (2) 25% CR from baseline energy requirements (CR group); (3) 25% energy deficit by a combination of CR and increased aerobic exercise (CR + EX group); and (4) low-calorie diet (890 kcal/d; goal, 15% weight loss) followed by weight maintenance (LCD group). Bone mineral density (total body and hip by dual-energy x-ray absorptiometry) and serum bone markers (bone-specific alkaline phosphatase, osteocalcin, cross-linked C-telopeptide of type I collagen, and cross-linked N-telopeptide of type I collagen) were measured at baseline and after 6 months. Mean +/- SE body weight was reduced by -1.0% +/- 1.1% (control), -10.4% +/- 0.9% (CR), -10.0% +/- 0.8% (CR + EX), and -13.9% +/- 0.7% (LCD). Compared with the control group, none of the groups showed any change in bone mineral density for total body or hip. Bone resorption by serum cross-linked C-telopeptide of type I collagen was increased in all 3 intervention groups, with the largest change observed in the LCD group (CR, 23% +/- 10%; CR + EX, 22% +/- 9%; and LCD, 74% +/- 16% vs control, 4% +/- 10%). Serum levels of cross-linked N-telopeptide of type I collagen were also increased in the LCD group. With regard to bone formation, bone alkaline phosphatase levels were decreased in the CR group (-23% +/- 10%) but were unchanged in the CR + EX, LCD, and control groups. Moderate CR, with or without exercise, that preserves calcium intake for 6 months leads to large changes in body composition without significant bone loss in young adults. Longer studies with assessments of bone architecture are needed to confirm that CR nutrient-dense diets have no deleterious effect on bone health. clinicaltrials.gov Identifier: NCT00099151.

Hexavalent chromium induced stress and metabolic responses in hybrid willows.

PubMed

Yu, Xiao-Zhang; Gu, Ji-Dong; Huang, Shen-Zhuo

2007-04-01

Metabolic responses to hexavalent chromium (Cr(6+)) stress and the uptake and translocation of Cr(6+ )were investigated using pre-rooted hybrid willows (Salix matsudana Koidz x Salix alba L.) exposed to hydroponic solution spiked with K(2)CrO(4) at 24.0 +/- 1 degrees C for 192 h. Various physiological parameters of the plants were monitored to determine toxicity from Cr(6+ )exposure. At Cr(6+) treatments of 50% higher than that of the non-treated control plants. As Cr concentrations were increased further, a slight increase in the transpiration rate was also observed compared with the controls. Negligible difference in the chlorophyll contents in leaves between the treated and the non-treated control plants was measured, except for willows exposed to 1.05 mg Cr/l. The response of soluble proteins in leaves of willows to Cr treatments was remarkable. Cr-induced toxicity appeared in all treatments resulting in reduced activities of catalase (CAT) and peroxidase (POD) compared to the controls. Superoxide dismutases (SOD) activity in the leaf cells showed a positive increase after Cr exposure. Of all selected parameters, soluble proteins in leaves were the most sensitive to Cr(6+ )doses, showing a significant linear correlation negatively (R (2) = 0.931). Uptake of Cr(6+) by willows grown in flasks was found to increase linearly with the added Cr(6+ )(a zero order kinetics), as indicated by the high R (2) (0.9322). Recovery of Cr in different parts of plant materials varied significantly with roots being the dominant site of Cr accumulation. Although the translocation to shoots was detected, the amount of Cr translocated to shoots was considerably small. The capacity of willows to assimilate Cr(6+ )was also evaluated using detached leaves and roots in sealed glass vessels in vivo. Uptake of Cr by roots was mediated possibly through an active transport mechanism, whereas the cuticle of leaves was the major obstacle to uptake Cr from the hydroponic solution. In addition, both cysteine and ascorbic acid showed a remarkable potential to reduce Cr(6+) at a neutral pH. Results indicated that the added Cr did not cause deleterious effects on plant physiological functions over a 192-h period of exposure. Significant removal of Cr from the hydroponic solution was observed in the presence of hybrid willows. The data also suggest that phytoremediation of Cr(6+) is possible and ecologically safe due to the minor translocation of Cr to aerial tissues.

Changes in selected serum parameters of broiler chicken fed supplemental chromium.

PubMed

Króliczewska, B; Zawadzki, W; Dobrzanski, Z; Kaczmarek-Oliwa, A

2004-12-01

The present study was conducted to evaluate the effect of chromium (Cr) from Cr yeast on the growth performance and total cholesterol, high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol, triglycerides, glucose, total protein and Cr concentration in the serum of broiler chicken. The birds were fed a control diet or a control diet supplemented with Cr at a level of 300, 500 microg/kg Cr. The supplementation of 500 mug/kg Cr increased body weight, weight gain and feed efficiency (p < 0.05). In addition, supplementation with Cr decreased the serum total cholesterol, LDL cholesterol (p < 0.05), triglycerides (p < 0.05) and glucose (p < 0.05) concentrations whereas serum HDL cholesterol increased. Serum total protein and serum Cr concentration slightly but not significantly increased in both Cr groups. The study suggest that Cr supplementation particularly at 500 microg/kg Cr from Cr yeast can influence on carbohydrate and lipid metabolism of broiler chicken and can be used as additives in animal diet but it still needs more investigations.

Genetic divergence and fine scale population structure of the common bottlenose dolphin (Tursiops truncatus, Montagu) found in the Gulf of Guayaquil, Ecuador

PubMed Central

Bayas-Rea, Rosa de los Ángeles; Félix, Fernando

2018-01-01

The common bottlenose dolphin, Tursiops truncatus, is widely distributed along the western coast of South America. In Ecuador, a resident population of bottlenose dolphins inhabits the inner estuarine area of the Gulf of Guayaquil located in the southwestern part of the country and is under threat from different human activities in the area. Only one genetic study on South American common bottlenose dolphins has been carried out to date, and understanding genetic variation of wildlife populations, especially species that are identified as threatened, is crucial for defining conservation units and developing appropriate conservation strategies. In order to evaluate the evolutionary link of this population, we assessed the phylogenetic relationships, phylogeographic patterns, and population structure using mitochondrial DNA (mtDNA). The sampling comprised: (i) 31 skin samples collected from free-ranging dolphins at three locations in the Gulf of Guayaquil inner estuary, (ii) 38 samples from stranded dolphins available at the collection of the “Museo de Ballenas de Salinas,” (iii) 549 mtDNA control region (mtDNA CR) sequences from GenBank, and (iv) 66 concatenated sequences from 7-mtDNA regions (12S rRNA, 16S rRNA, NADH dehydrogenase subunit I–II, cytochrome oxidase I and II, cytochrome b, and CR) obtained from mitogenomes available in GenBank. Our analyses indicated population structure between both inner and outer estuary dolphin populations as well as with distinct populations of T. truncatus using mtDNA CR. Moreover, the inner estuary bottlenose dolphin (estuarine bottlenose dolphin) population exhibited lower levels of genetic diversity than the outer estuary dolphin population according to the mtDNA CR. Finally, the estuarine bottlenose dolphin population was genetically distinct from other T. truncatus populations based on mtDNA CR and 7-mtDNA regions. From these results, we suggest that the estuarine bottlenose dolphin population should be considered a distinct lineage. This dolphin population faces a variety of anthropogenic threats in this area; thus, we highlight its fragility and urge authorities to issue prompt management and conservation measures. PMID:29707430

Effects of irradiation combined with cis-diamminedichloroplatinum (CDDP) suppository in rabbit VX2 rectal tumors.

PubMed

Wakatsuki, Kazuo; Oda, Kenji; Koda, Keiji; Seike, Kazuhiro; Takiguchi, Nobuhiro; Saito, Norio; Miyazaki, Masaru

2005-03-01

To decrease local recurrence and increase disease free survival, various preoperative therapies for patients with advanced rectal cancer have been studied. Cis-diamminedichloroplatinum (II) (CDDP) has become one of the most widely used cancer chemotherapeutic drugs. It has also been found to have radiosensitizing properties. In this experimental study, the efficacy of chemoradiotherapy using a novel CDDP suppository, and one with mixed micelles, was examined in a rabbit VX2 rectal tumor model. Rabbits were divided into four groups: control group, irradiation (R) group, CDDP suppository plus irradiation (CR) group, and mixed micelles plus CDDP suppository plus irradiation (CMR) group. Tumor growth ratios were reduced significantly in the CR and CMR groups as compared with the ratio in the control group. Microscopically, response rates of main tumors were 0%, 33.3%, 70.0%, and 91. 7%, respectively. The number of metastatic lymph nodes in the CR and CMR groups decreased significantly compared to the control group and the R group. The microscopic response rates of metastatic lymph nodes were 0%, 11.1%, 40.0%, and 41.7%, respectively. Lung metastases were observed in three rabbits in the R group, and in one rabbit in the CMR group. Tissue platinum concentrations both in tumors and in regional lymph nodes increased significantly when mixed micelles were used. Chemoradiotherapy using the CDDP suppository and mixed micelles was effective for local control in the rabbit VX2 rectal tumor model.

Asparaginase treatment side-effects may be due to genes with homopolymeric Asn codons (Review-Hypothesis)

PubMed Central

BANERJI, JULIAN

2015-01-01

The present treatment of childhood T-cell leukemias involves the systemic administration of prokary-otic L-asparaginase (ASNase), which depletes plasma Asparagine (Asn) and inhibits protein synthesis. The mechanism of therapeutic action of ASNase is poorly understood, as are the etiologies of the side-effects incurred by treatment. Protein expression from genes bearing Asn homopolymeric coding regions (N-hCR) may be particularly susceptible to Asn level fluctuation. In mammals, N-hCR are rare, short and conserved. In humans, misfunctions of genes encoding N-hCR are associated with a cluster of disorders that mimic ASNase therapy side-effects which include impaired glycemic control, dislipidemia, pancreatitis, compromised vascular integrity, and neurological dysfunction. This paper proposes that dysregulation of Asn homeostasis, potentially even by ASNase produced by the microbiome, may contribute to several clinically important syndromes by altering expression of N-hCR bearing genes. By altering amino acid abundance and modulating ribosome translocation rates at codon repeats, the microbiomic environment may contribute to genome decoding and to shaping the proteome. We suggest that impaired translation at poly Asn codons elevates diabetes risk and severity. PMID:26178806

Asparaginase treatment side-effects may be due to genes with homopolymeric Asn codons (Review-Hypothesis).

PubMed

Banerji, Julian

2015-09-01

The present treatment of childhood T-cell leukemias involves the systemic administration of prokaryotic L-asparaginase (ASNase), which depletes plasma Asparagine (Asn) and inhibits protein synthesis. The mechanism of therapeutic action of ASNase is poorly understood, as are the etiologies of the side-effects incurred by treatment. Protein expression from genes bearing Asn homopolymeric coding regions (N-hCR) may be particularly susceptible to Asn level fluctuation. In mammals, N-hCR are rare, short and conserved. In humans, misfunctions of genes encoding N-hCR are associated with a cluster of disorders that mimic ASNase therapy side-effects which include impaired glycemic control, dislipidemia, pancreatitis, compromised vascular integrity, and neurological dysfunction. This paper proposes that dysregulation of Asn homeostasis, potentially even by ASNase produced by the microbiome, may contribute to several clinically important syndromes by altering expression of N-hCR bearing genes. By altering amino acid abundance and modulating ribosome translocation rates at codon repeats, the microbiomic environment may contribute to genome decoding and to shaping the proteome. We suggest that impaired translation at poly Asn codons elevates diabetes risk and severity.

Flow microcapillary plasma mass spectrometry-based investigation of new Al-Cr-Fe complex metallic alloy passivation.

PubMed

Ott, N; Beni, A; Ulrich, A; Ludwig, C; Schmutz, P

2014-03-01

Al-Cr-Fe complex metallic alloys are new intermetallic phases with low surface energy, low friction, and high corrosion resistance down to very low pH values (0-2). Flow microcapillary plasma mass spectrometry under potentiostatic control was used to characterize the dynamic aspect of passivation of an Al-Cr-Fe gamma phase in acidic electrolytes, allowing a better insight on the parameters inducing chemical stability at the oxyhydroxide-solution interface. In sulfuric acid pH 0, low element dissolution rates (in the µg cm(-2) range after 60 min) evidenced the passive state of the Al-Cr-Fe gamma phase with a preferential over-stoichiometric dissolution of Al and Fe cations. Longer air-aging was found to be beneficial for stabilizing the passive film. In chloride-containing electrolytes, ten times higher Al dissolution rates were detected at open-circuit potential (OCP), indicating that the spontaneously formed passive film becomes unstable. However, electrochemical polarization at low passive potentials induces electrical field generated oxide film modification, increasing chemical stability at the oxyhydroxide-solution interface. In the high potential passive region, localized attack is initiated with subsequent active metal dissolution. © 2013 Published by Elsevier B.V.

Effects of AEC chamber selection on patient dose and image quality.

PubMed

Hawking, Nancy; Elmore, Angie

2009-01-01

To determine whether manipulation of the standard automatic exposure control (AEC) chamber selections reduces the patient's entrance skin exposure (ESE) without compromising image quality. Data for density and radiation dose were gathered at 2 clinical locations by exposing abdomen and pelvis phantoms to radiation using 3 AEC chamber selection configurations. ESE (skin dose) was measured using a multipurpose dosimeter. The experiment included both film-screen and computed radiography (CR) systems. For both phantoms, using the 2 outside chambers resulted in the lowest dose on the film-screen and CR systems. In general, optical density (OD) and exposure indicator (EI) remained within acceptable ranges and image quality was maintained using this chamber configuration. Using only the center chamber resulted in the highest dose increases and lowest image quality for film-screen and CR systems. When performing anteroposterior (AP) abdomen and AP pelvis examinations, radiographers can reduce patients' ESE and maintain image quality by selecting the 2 outside AEC chambers. Further research on AEC chamber selection should be conducted for additional anatomical regions.

Does Functional Connectivity Provide a Marker for Cognitive Rehabilitation Effects in Alzheimer's Disease? An Interventional Study.

PubMed

Ochmann, Sina; Dyrba, Martin; Grothe, Michel J; Kasper, Elisabeth; Webel, Steffi; Hauenstein, Karlheinz; Teipel, Stefan J

2017-01-01

Cognitive rehabilitation (CR) is a cognitive intervention for patients with Alzheimer's disease (AD) that aims to maintain everyday competences. The analysis of functional connectivity (FC) in resting-state functional MRI has been used to investigate the effects of cognitive interventions. We evaluated the effect of CR on the default mode network FC in a group of patients with mild AD, compared to an active control group. We performed a three-month interventional study including 16 patients with a diagnosis of AD. The intervention group (IG) consisted of eight patients, performing twelve sessions of CR. The active control group (CG) performed a standardized cognitive training. We used a seed region placed in the posterior cingulate cortex (PCC) for FC analysis, comparing scans acquired before and after the intervention. Effects were thresholded at a significance of p < 0.001 (uncorrected) and a minimal cluster size of 50 voxels. The interaction of group by time showed a higher increase of PCC connectivity in IG compared to CG in the bilateral cerebellar cortex. CG revealed widespread, smaller clusters of higher FC increase compared with IG. Across all participants, an increase in quality of life was associated with connectivity increase over time in the bilateral precuneus. CR showed an effect on the FC of the DMN in the IG. These effects need further study in larger samples to confirm if FC analysis may suit as a surrogate marker for the effect of cognitive interventions in AD.

Cerebral oxygen saturation and peripheral perfusion in the extremely premature infant with intraventricular and/or pulmonary haemorrhage early in life.

PubMed

Beausoleil, Thierry P; Janaillac, Marie; Barrington, Keith J; Lapointe, Anie; Dehaes, Mathieu

2018-04-25

Extremely preterm infants are at higher risk of pulmonary (PH) and intraventricular (IVH) haemorrhage during the transitioning physiology due to immature cardiovascular system. Monitoring of haemodynamics can detect early abnormal circulation that may lead to these complications. We described time-frequency relationships between near infrared spectroscopy (NIRS) cerebral regional haemoglobin oxygen saturation (CrSO 2 ) and preductal peripheral perfusion index (PI), capillary oxygen saturation (SpO 2 ) and heart rate (HR) in extremely preterm infants in the first 72 h of life. Patients were sub-grouped in infants with PH and/or IVH (N H  = 8) and healthy controls (N C  = 11). Data were decomposed in wavelets allowing the analysis of localized variations of power. This approach allowed to quantify the percentage of time of significant cross-correlation, semblance, gain (transfer function) and coherence between signals. Ultra-low frequencies (<0.28 mHz) were analyzed as slow and prolonged periods of impaired circulation are considered more detrimental than transient fluctuations. Cross-correlation between CrSO 2 and oximetry (PI, SpO 2 and HR) as well as in-phase semblance and gain between CrSO 2 and HR were significantly lower while anti-phase semblance between CrSO 2 and HR was significantly higher in PH-IVH infants compared to controls. These differences may reflect haemodynamic instability associated with cerebrovascular autoregulation and hemorrhagic complications observed during the transitioning physiology.

Complete mitochondrial genome of the giant African snail, Achatina fulica (Mollusca: Achatinidae): a novel location of putative control regions (CR) in the mitogenome within Pulmonate species.

PubMed

He, Zhang-Ping; Dai, Xia-Bin; Zhang, Shuai; Zhi, Ting-Ting; Lun, Zhao-Rong; Wu, Zhong-Dao; Yang, Ting-Bao

2016-01-01

The whole sequence (15,057 bp) of the mitochondrial DNA (mtDNA) of the terrestrial snail Achatina fulica (order Stylommatophora) was determined. The mitogenome, as the typical metazoan mtDNA, contains 13 protein-coding genes (PCG), 2 ribosomal RNA genes (rRNA) and 22 transfer RNA genes (tRNA). The tRNA genes include two trnS without standard secondary structure. Interestingly, among the known mitogenomes of Pulmonata species, we firstly characterized an unassigned lengthy sequence (551 bp) between the cox1 and the trnV which may be the CR for the sake of its AT bases usage bias (65.70%) and potential hairpin structure.

Partial mitochondrial gene arrangements support a close relationship between Tardigrada and Arthropoda.

PubMed

Ryu, Shi Hyun; Lee, Ji Min; Jang, Kuem-Hee; Choi, Eun Hwa; Park, Shin Ju; Chang, Cheon Young; Kim, Won; Hwang, Ui Wook

2007-12-31

Regions (about 3.7-3.8 kb) of the mitochondrial genomes (rrnL-cox1) of two tardigrades, a heterotardigrade, Batillipes pennaki, and a eutardigrade, Pseudobiotus spinifer, were sequenced and characterized. The gene order in Batillipes was rrnL-V-rrnS-Q-I-M-nad2-W-C-Y-cox1, and in Pseudobiotus it was rrnL-V-rrnS-Q-M-nad2-W-C-Y-cox1. With the exception of the trnI gene, the two tardigrade regions have the same gene content and order. Their gene orders are strikingly similar to that of the chelicerate Limulus polyphemus (rrnL-V-rrnS-CR-I-Q-M-nad2-W-C-Y-cox1), which is considered to be ancestral for arthropods. Although the tardigrades do not have a distinct control region (CR) within this segment, the trnI gene in Pseudobiotus is located between rrnL-trnL1 and trnL2-nad1, and the trnI gene in Batillipes is located between trnQ and trnM. In addition, the 106-bp region between trnQ and trnM in Batillipes not only contains two plausible trnI genes with opposite orientations, but also exhibits some CR-like characteristics. The mitochondrial gene arrangements of 183 other protostomes were compared. 60 (52.2%) of the 115 arthropods examined have the M-nad2-W-C-Y-cox1 arrangement, and 88 (76.5%) the M-nad2-W arrangement, as found in the tardigrades. In contrast, no such arrangement was seen in the 70 non-arthropod protostomes studied. These are the first non-sequence molecular data that support the close relationship of tardigrades and arthropods.

Far-infrared observations of a star-forming region in the Corona Australis dark cloud

NASA Technical Reports Server (NTRS)

Cruz-Gonzalez, I.; Mcbreen, B.; Fazio, G. G.

1984-01-01

A high-resolution far-IR (40-250-micron) survey of a 0.9-sq-deg section of the core region of the Corona Australis dark cloud (containing very young stellar objects such as T Tauri stars, Herbig Ae and Be stars, Herbig-Haro objects, and compact H II regions) is presented. Two extended far-IR sources were found, one associated with the Herbig emission-line star R CrA and the other with the irregular emission-line variable star TY CrA. The two sources have substantially more far-IR radiation than could be expected from a blackbody extrapolation of their near-IR fluxes. The total luminosities of these sources are 145 and 58 solar luminosity, respectively, implying that the embedded objects are of intermediate or low mass. The infrared observations of the sources associated with R CrA and TY CrA are consistent with models of the evolution of protostellar envelopes of intermediate mass. However, the TY CrA source appears to have passed the evolutionary stage of expelling most of the hot dust near the central source, yielding an age of about 1 Myr.

Identification and characterization of novel associations in the CASP8/ALS2CR12 region on chromosome 2 with breast cancer risk

PubMed Central

Lin, Wei-Yu; Camp, Nicola J.; Ghoussaini, Maya; Beesley, Jonathan; Michailidou, Kyriaki; Hopper, John L.; Apicella, Carmel; Southey, Melissa C.; Stone, Jennifer; Schmidt, Marjanka K.; Broeks, Annegien; Van't Veer, Laura J.; Th Rutgers, Emiel J.; Muir, Kenneth; Lophatananon, Artitaya; Stewart-Brown, Sarah; Siriwanarangsan, Pornthep; Fasching, Peter A.; Haeberle, Lothar; Ekici, Arif B.; Beckmann, Matthias W.; Peto, Julian; Dos-Santos-Silva, Isabel; Fletcher, Olivia; Johnson, Nichola; Bolla, Manjeet K.; Wang, Qin; Dennis, Joe; Sawyer, Elinor J.; Cheng, Timothy; Tomlinson, Ian; Kerin, Michael J.; Miller, Nicola; Marmé, Frederik; Surowy, Harald M.; Burwinkel, Barbara; Guénel, Pascal; Truong, Thérèse; Menegaux, Florence; Mulot, Claire; Bojesen, Stig E.; Nordestgaard, Børge G.; Nielsen, Sune F.; Flyger, Henrik; Benitez, Javier; Zamora, M. Pilar; Arias Perez, Jose Ignacio; Menéndez, Primitiva; González-Neira, Anna; Pita, Guillermo; Alonso, M. Rosario; Álvarez, Nuria; Herrero, Daniel; Anton-Culver, Hoda; Brenner, Hermann; Dieffenbach, Aida Karina; Arndt, Volker; Stegmaier, Christa; Meindl, Alfons; Lichtner, Peter; Schmutzler, Rita K.; Müller-Myhsok, Bertram; Brauch, Hiltrud; Brüning, Thomas; Ko, Yon-Dschun; Tessier, Daniel C.; Vincent, Daniel; Bacot, Francois; Nevanlinna, Heli; Aittomäki, Kristiina; Blomqvist, Carl; Khan, Sofia; Matsuo, Keitaro; Ito, Hidemi; Iwata, Hiroji; Horio, Akiyo; Bogdanova, Natalia V.; Antonenkova, Natalia N.; Dörk, Thilo; Lindblom, Annika; Margolin, Sara; Mannermaa, Arto; Kataja, Vesa; Kosma, Veli-Matti; Hartikainen, Jaana M.; Wu, Anna H.; Tseng, Chiu-Chen; Van Den Berg, David; Stram, Daniel O.; Neven, Patrick; Wauters, Els; Wildiers, Hans; Lambrechts, Diether; Chang-Claude, Jenny; Rudolph, Anja; Seibold, Petra; Flesch-Janys, Dieter; Radice, Paolo; Peterlongo, Paolo; Manoukian, Siranoush; Bonanni, Bernardo; Couch, Fergus J.; Wang, Xianshu; Vachon, Celine; Purrington, Kristen; Giles, Graham G.; Milne, Roger L.; Mclean, Catriona; Haiman, Christopher A.; Henderson, Brian E.; Schumacher, Fredrick; Le Marchand, Loic; Simard, Jacques; Goldberg, Mark S.; Labrèche, France; Dumont, Martine; Teo, Soo Hwang; Yip, Cheng Har; Hassan, Norhashimah; Vithana, Eranga Nishanthie; Kristensen, Vessela; Zheng, Wei; Deming-Halverson, Sandra; Shrubsole, Martha J.; Long, Jirong; Winqvist, Robert; Pylkäs, Katri; Jukkola-Vuorinen, Arja; Kauppila, Saila; Andrulis, Irene L.; Knight, Julia A.; Glendon, Gord; Tchatchou, Sandrine; Devilee, Peter; Tollenaar, Robert A.E.M.; Seynaeve, Caroline; Van Asperen, Christi J.; García-Closas, Montserrat; Figueroa, Jonine; Lissowska, Jolanta; Brinton, Louise; Czene, Kamila; Darabi, Hatef; Eriksson, Mikael; Brand, Judith S.; Hooning, Maartje J.; Hollestelle, Antoinette; Van Den Ouweland, Ans M.W.; Jager, Agnes; Li, Jingmei; Liu, Jianjun; Humphreys, Keith; Shu, Xiao-Ou; Lu, Wei; Gao, Yu-Tang; Cai, Hui; Cross, Simon S.; Reed, Malcolm W. R.; Blot, William; Signorello, Lisa B.; Cai, Qiuyin; Pharoah, Paul D.P.; Perkins, Barbara; Shah, Mitul; Blows, Fiona M.; Kang, Daehee; Yoo, Keun-Young; Noh, Dong-Young; Hartman, Mikael; Miao, Hui; Chia, Kee Seng; Putti, Thomas Choudary; Hamann, Ute; Luccarini, Craig; Baynes, Caroline; Ahmed, Shahana; Maranian, Mel; Healey, Catherine S.; Jakubowska, Anna; Lubinski, Jan; Jaworska-Bieniek, Katarzyna; Durda, Katarzyna; Sangrajrang, Suleeporn; Gaborieau, Valerie; Brennan, Paul; Mckay, James; Slager, Susan; Toland, Amanda E.; Yannoukakos, Drakoulis; Shen, Chen-Yang; Hsiung, Chia-Ni; Wu, Pei-Ei; Ding, Shian-ling; Ashworth, Alan; Jones, Michael; Orr, Nick; Swerdlow, Anthony J; Tsimiklis, Helen; Makalic, Enes; Schmidt, Daniel F.; Bui, Quang M.; Chanock, Stephen J.; Hunter, David J.; Hein, Rebecca; Dahmen, Norbert; Beckmann, Lars; Aaltonen, Kirsimari; Muranen, Taru A.; Heikkinen, Tuomas; Irwanto, Astrid; Rahman, Nazneen; Turnbull, Clare A.; Waisfisz, Quinten; Meijers-Heijboer, Hanne E. J.; Adank, Muriel A.; Van Der Luijt, Rob B.; Hall, Per; Chenevix-Trench, Georgia; Dunning, Alison; Easton, Douglas F.; Cox, Angela

2015-01-01

Previous studies have suggested that polymorphisms in CASP8 on chromosome 2 are associated with breast cancer risk. To clarify the role of CASP8 in breast cancer susceptibility, we carried out dense genotyping of this region in the Breast Cancer Association Consortium (BCAC). Single-nucleotide polymorphisms (SNPs) spanning a 1 Mb region around CASP8 were genotyped in 46 450 breast cancer cases and 42 600 controls of European origin from 41 studies participating in the BCAC as part of a custom genotyping array experiment (iCOGS). Missing genotypes and SNPs were imputed and, after quality exclusions, 501 typed and 1232 imputed SNPs were included in logistic regression models adjusting for study and ancestry principal components. The SNPs retained in the final model were investigated further in data from nine genome-wide association studies (GWAS) comprising in total 10 052 case and 12 575 control subjects. The most significant association signal observed in European subjects was for the imputed intronic SNP rs1830298 in ALS2CR12 (telomeric to CASP8), with per allele odds ratio and 95% confidence interval [OR (95% confidence interval, CI)] for the minor allele of 1.05 (1.03–1.07), P = 1 × 10−5. Three additional independent signals from intronic SNPs were identified, in CASP8 (rs36043647), ALS2CR11 (rs59278883) and CFLAR (rs7558475). The association with rs1830298 was replicated in the imputed results from the combined GWAS (P = 3 × 10−6), yielding a combined OR (95% CI) of 1.06 (1.04–1.08), P = 1 × 10−9. Analyses of gene expression associations in peripheral blood and normal breast tissue indicate that CASP8 might be the target gene, suggesting a mechanism involving apoptosis. PMID:25168388

Identification and characterization of novel associations in the CASP8/ALS2CR12 region on chromosome 2 with breast cancer risk.

PubMed

Lin, Wei-Yu; Camp, Nicola J; Ghoussaini, Maya; Beesley, Jonathan; Michailidou, Kyriaki; Hopper, John L; Apicella, Carmel; Southey, Melissa C; Stone, Jennifer; Schmidt, Marjanka K; Broeks, Annegien; Van't Veer, Laura J; Th Rutgers, Emiel J; Muir, Kenneth; Lophatananon, Artitaya; Stewart-Brown, Sarah; Siriwanarangsan, Pornthep; Fasching, Peter A; Haeberle, Lothar; Ekici, Arif B; Beckmann, Matthias W; Peto, Julian; Dos-Santos-Silva, Isabel; Fletcher, Olivia; Johnson, Nichola; Bolla, Manjeet K; Wang, Qin; Dennis, Joe; Sawyer, Elinor J; Cheng, Timothy; Tomlinson, Ian; Kerin, Michael J; Miller, Nicola; Marmé, Frederik; Surowy, Harald M; Burwinkel, Barbara; Guénel, Pascal; Truong, Thérèse; Menegaux, Florence; Mulot, Claire; Bojesen, Stig E; Nordestgaard, Børge G; Nielsen, Sune F; Flyger, Henrik; Benitez, Javier; Zamora, M Pilar; Arias Perez, Jose Ignacio; Menéndez, Primitiva; González-Neira, Anna; Pita, Guillermo; Alonso, M Rosario; Alvarez, Nuria; Herrero, Daniel; Anton-Culver, Hoda; Brenner, Hermann; Dieffenbach, Aida Karina; Arndt, Volker; Stegmaier, Christa; Meindl, Alfons; Lichtner, Peter; Schmutzler, Rita K; Müller-Myhsok, Bertram; Brauch, Hiltrud; Brüning, Thomas; Ko, Yon-Dschun; Tessier, Daniel C; Vincent, Daniel; Bacot, Francois; Nevanlinna, Heli; Aittomäki, Kristiina; Blomqvist, Carl; Khan, Sofia; Matsuo, Keitaro; Ito, Hidemi; Iwata, Hiroji; Horio, Akiyo; Bogdanova, Natalia V; Antonenkova, Natalia N; Dörk, Thilo; Lindblom, Annika; Margolin, Sara; Mannermaa, Arto; Kataja, Vesa; Kosma, Veli-Matti; Hartikainen, Jaana M; Wu, Anna H; Tseng, Chiu-Chen; Van Den Berg, David; Stram, Daniel O; Neven, Patrick; Wauters, Els; Wildiers, Hans; Lambrechts, Diether; Chang-Claude, Jenny; Rudolph, Anja; Seibold, Petra; Flesch-Janys, Dieter; Radice, Paolo; Peterlongo, Paolo; Manoukian, Siranoush; Bonanni, Bernardo; Couch, Fergus J; Wang, Xianshu; Vachon, Celine; Purrington, Kristen; Giles, Graham G; Milne, Roger L; Mclean, Catriona; Haiman, Christopher A; Henderson, Brian E; Schumacher, Fredrick; Le Marchand, Loic; Simard, Jacques; Goldberg, Mark S; Labrèche, France; Dumont, Martine; Teo, Soo Hwang; Yip, Cheng Har; Hassan, Norhashimah; Vithana, Eranga Nishanthie; Kristensen, Vessela; Zheng, Wei; Deming-Halverson, Sandra; Shrubsole, Martha J; Long, Jirong; Winqvist, Robert; Pylkäs, Katri; Jukkola-Vuorinen, Arja; Kauppila, Saila; Andrulis, Irene L; Knight, Julia A; Glendon, Gord; Tchatchou, Sandrine; Devilee, Peter; Tollenaar, Robert A E M; Seynaeve, Caroline; Van Asperen, Christi J; García-Closas, Montserrat; Figueroa, Jonine; Lissowska, Jolanta; Brinton, Louise; Czene, Kamila; Darabi, Hatef; Eriksson, Mikael; Brand, Judith S; Hooning, Maartje J; Hollestelle, Antoinette; Van Den Ouweland, Ans M W; Jager, Agnes; Li, Jingmei; Liu, Jianjun; Humphreys, Keith; Shu, Xiao-Ou; Lu, Wei; Gao, Yu-Tang; Cai, Hui; Cross, Simon S; Reed, Malcolm W R; Blot, William; Signorello, Lisa B; Cai, Qiuyin; Pharoah, Paul D P; Perkins, Barbara; Shah, Mitul; Blows, Fiona M; Kang, Daehee; Yoo, Keun-Young; Noh, Dong-Young; Hartman, Mikael; Miao, Hui; Chia, Kee Seng; Putti, Thomas Choudary; Hamann, Ute; Luccarini, Craig; Baynes, Caroline; Ahmed, Shahana; Maranian, Mel; Healey, Catherine S; Jakubowska, Anna; Lubinski, Jan; Jaworska-Bieniek, Katarzyna; Durda, Katarzyna; Sangrajrang, Suleeporn; Gaborieau, Valerie; Brennan, Paul; Mckay, James; Slager, Susan; Toland, Amanda E; Yannoukakos, Drakoulis; Shen, Chen-Yang; Hsiung, Chia-Ni; Wu, Pei-Ei; Ding, Shian-Ling; Ashworth, Alan; Jones, Michael; Orr, Nick; Swerdlow, Anthony J; Tsimiklis, Helen; Makalic, Enes; Schmidt, Daniel F; Bui, Quang M; Chanock, Stephen J; Hunter, David J; Hein, Rebecca; Dahmen, Norbert; Beckmann, Lars; Aaltonen, Kirsimari; Muranen, Taru A; Heikkinen, Tuomas; Irwanto, Astrid; Rahman, Nazneen; Turnbull, Clare A; Waisfisz, Quinten; Meijers-Heijboer, Hanne E J; Adank, Muriel A; Van Der Luijt, Rob B; Hall, Per; Chenevix-Trench, Georgia; Dunning, Alison; Easton, Douglas F; Cox, Angela

2015-01-01

Previous studies have suggested that polymorphisms in CASP8 on chromosome 2 are associated with breast cancer risk. To clarify the role of CASP8 in breast cancer susceptibility, we carried out dense genotyping of this region in the Breast Cancer Association Consortium (BCAC). Single-nucleotide polymorphisms (SNPs) spanning a 1 Mb region around CASP8 were genotyped in 46 450 breast cancer cases and 42 600 controls of European origin from 41 studies participating in the BCAC as part of a custom genotyping array experiment (iCOGS). Missing genotypes and SNPs were imputed and, after quality exclusions, 501 typed and 1232 imputed SNPs were included in logistic regression models adjusting for study and ancestry principal components. The SNPs retained in the final model were investigated further in data from nine genome-wide association studies (GWAS) comprising in total 10 052 case and 12 575 control subjects. The most significant association signal observed in European subjects was for the imputed intronic SNP rs1830298 in ALS2CR12 (telomeric to CASP8), with per allele odds ratio and 95% confidence interval [OR (95% confidence interval, CI)] for the minor allele of 1.05 (1.03-1.07), P = 1 × 10(-5). Three additional independent signals from intronic SNPs were identified, in CASP8 (rs36043647), ALS2CR11 (rs59278883) and CFLAR (rs7558475). The association with rs1830298 was replicated in the imputed results from the combined GWAS (P = 3 × 10(-6)), yielding a combined OR (95% CI) of 1.06 (1.04-1.08), P = 1 × 10(-9). Analyses of gene expression associations in peripheral blood and normal breast tissue indicate that CASP8 might be the target gene, suggesting a mechanism involving apoptosis. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Neoadjuvant oral vs. infusional chemoradiotherapy on locally advanced rectal cancer: Prognostic factors.

PubMed

Conde, Sofia; Borrego, Margarida; Teixeira, Tânia; Teixeira, Rubina; Sá, Anabela; Soares, Paula

2012-01-01

To evaluate the prognostic factors and impact on survival of neoadjuvant oral and infusional chemoradiotherapy in patients with locally advanced rectal cancer. There is still no definitive consensus about the prognostic factors and the impact of neoadjuvant chemoradiotherapy on survival. Some studies have pointed to an improvement in overall survival (OS) and progression-free survival (PFS) in patients with tumor downstaging (TD) and nodal downstaging (ND). A set of 159 patients with LARC were treated preoperatively. Group A - 112 patients underwent concomitant oral chemoradiotherapy: capecitabine or UFT + folinic acid. Group B - 47 patients submitted to concomitant chemoradiation with 5-FU in continuous infusion. 63.6% of patients were submitted to adjuvant chemotherapy. pathologic complete response (pCR) - 18.7%; TD - 55.1%; ND - 76%; loco-regional response - 74.8%. Group B: pCR - 11.4%; TD - 50%; ND - 55.8%; LRR - 54.5%. The loco-regional control was 95.6%. There was no difference in survival between both groups. Those with loco-regional response had better PFS. Tumor and nodal downstaging, loco-regional response and a normal CEA level turned out to be important prognostic factors in locally advanced rectal cancer. Nodal downstaging and loco-regional response were higher in Group A. Those with tumor downstaging and loco-regional response from Group A had better OS. Adjuvant chemotherapy had no impact on survival except in those patients with loco-regional response who achieved a higher PFS.

Efficacy of dietary chromium (III) supplementation on tissue chromium deposition in finishing pigs.

PubMed

Wang, Min-Qi; Li, Hui; He, Yu-Dan; Wang, Chao; Tao, Wen-Jing; Du, Yong-Jie

2012-09-01

The study was conducted to evaluate the efficacy of different forms of trivalent chromium (Cr) supplementation on tissue chromium deposition in finishing pigs. A total of 96 pigs with an initial average body mass 65.57±1.05 kg were blocked by body mass and randomly assigned to four treatments with three replicates. Pigs were offered one of four diets including a control diet or the control diet supplemented with 200 μg/kg chromium from either chromium chloride (CrCl(3)), chromium picolinate (CrPic) or chromium nanocomposite (CrNano) for 40 days. During the trial, all pigs were given free access to feed and water. After feeding trial, eight pigs from each treatment were slaughtered for samples collection. The results showed that supplemental CrNano increased Cr content in blood, longissimus muscle, heart, liver, kidney, jejunum, and ileum (P<0.05). Supplemental Cr from three sources increased Cr excretion from all feces (P<0.05). Urinary Cr excretion was increased by CrNano or CrPic supplementation significantly. These results suggested that chromium nanocomposite exhibited more effective on tissue Cr deposition in pigs, which indicated higher absorption compared with CrCl(3) and CrPic.

Oxidation products of INCONEL alloys 600 and 690 in pressurized water reactor environments and their role in intergranular stress corrosion cracking

NASA Astrophysics Data System (ADS)

Ferguson, J. B.; Lopez, Hugo F.

2006-08-01

In this work, thermodynamic arguments for the stability of Ni and Cr compounds developed under pressurized water reactor environments ( P_{H_2 O} and P_{H_2 } ) were experimentally tested. A mechanism is proposed to explain crack initiation and propagation alloy 600 along the grain boundaries, where Cr2O3 has formed from the leaching of Cr from the matrix, leaving behind a porous Ni-rich region. The mechanism is based on the thermodynamic potential for the transformation of a protective NiO surface layer into an amorphous nonprotective Ni(OH)2 gel. This gel would also form along the grain boundaries and when hydrogenated steam reaches the porous Ni-rich regions. Crack initiation is then favored by tensile stressing of the grain boundary regions, which can easily rupture the gelatinous film. The leaching of matrix Cr to form nonprotective CrOOH gel at the crack tip followed by the exposure of fresh porous Ni to the environment could explain crack propagation in INCONEL alloy 600. The proposed crack initiation mechanism is not expected to occur in alloy 690 where a protective Cr2O3 film covers the entire metal surface. However, crack propagation along the grain boundaries in alloy 600 and precracked alloy 690 is expected to be active as hydroxide-forming reactions weaken the boundaries.

Biomarkers of oxidative stress in electroplating workers exposed to hexavalent chromium.

PubMed

Pan, Chih-Hong; Jeng, Hueiwang Anna; Lai, Ching-Huang

2018-01-01

This study evaluates levels of biomarkers of oxidative DNA damage and lipid peroxidation in 105 male workers at 16 electroplating companies who had been exposed to hexavalent chromium (Cr(VI)). The study participants were 230 non-smoking male workers, comprising 105 electroplating workers who had been exposed to chromium and 125 control subjects who performed office tasks. Personal air samples, spot urine samples, hair samples, fingernail samples and questionnaires were used to quantify exposure to Cr(VI), oxidative DNA damage, lipid peroxidation, and environmental pollutants. Both the geometric mean personal concentrations of Cr(VI) of the Cr-exposed workers and the total Cr concentrations in the air to which they were exposed significantly exceeded those for the control subjects. The geometric mean concentrations of Cr in urine, hair and fingernails, and the urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG), and malondialdehyde (MDA) levels in the Cr(VI) exposed workers exceeded those in the control subjects. Daily cumulative Cr(VI) exposure and urinary Cr were significantly correlated with urinary 8-OHdG levels following adjustments for covariates. A ten-fold increase in urinary Cr level was associated with a 1.73-fold increase in urinary 8-OHdG level. Daily cumulative Cr(VI) exposure and urinary Cr level were significantly correlated with urinary MDA level following adjustments for covariates. A ten-fold increase in urinary Cr was associated with a 1.45-fold increase in urinary MDA. Exposure to Cr(VI) increased oxidative DNA injury and the oxidative deterioration of lipids in electroplating workers.

The controlled release of bioactive compounds from lignin and lignin-based biopolymer matrices.

PubMed

Chowdhury, Mohammad A

2014-04-01

This article presents the perspectives on the lignin-based controlled release (CR) of bioactive materials which are based on the researches that took place over the last three decades. It encompasses three broad spectra of observations: CR formulations with mixed-matrix of lignin; CR formulations with modified lignin; and the lignin-based CR formulation modelling. The article covers a range of bioactive materials aimed for agricultural utilisations viz. herbicides, pesticides, insecticides and fertilisers for their controlled release studies, which were formulated either with lignin or lignin-based biopolymers. The inherent complexities, structural heterogeneities, and the presence of myriad range of functionalities in the lignin structure make it difficult to understand and explaining the underlying CR behaviour and process. In conjunction to this issue, the fundamental aspects of the synthetic and biocompatible polymer-based drug controlled release process are presented, and correlated with the lignin-based CR research. The articulation of this correlation and the overview presented in this article may be complemented of the future lignin-based CR research gaining better insights, reflections, and understanding. A recommended approach on the lignin depolymerisation is suggested to fragmenting the lignin, which may be tailored further using the re-polymerisation or other synthetic approaches. Thus it may allow more control with flexibilities and improved properties of the modified lignin materials, and help achieve the desired CR outcomes. Copyright © 2014 Elsevier B.V. All rights reserved.

Regional intra-arterial vs. systemic chemotherapy for advanced pancreatic cancer: a systematic review and meta-analysis of randomized controlled trials.

PubMed

Liu, Fenghua; Tang, Yong; Sun, Junwei; Yuan, Zhanna; Li, Shasha; Sheng, Jun; Ren, He; Hao, Jihui

2012-01-01

To investigate the efficacy and safety of regional intra-arterial chemotherapy (RIAC) versus systemic chemotherapy for stage III/IV pancreatic cancer. Randomized controlled trials of patients with advanced pancreatic cancer treated by regional intra-arterial or systemic chemotherapy were identified using PubMed, ISI, EMBASE, Cochrane Library, Google, Chinese Scientific Journals Database (VIP), and China National Knowledge Infrastructure (CNKI) electronic databases, for all publications dated between 1960 and December 31, 2010. Data was independently extracted by two reviewers. Odds ratios and relative risks were pooled using either fixed- or random-effects models, depending on I(2) statistic and Q test assessments of heterogeneity. Statistical analysis was performed using RevMan 5.0. Six randomized controlled trials comprised of 298 patients met the standards for inclusion in the meta-analysis, among 492 articles that were identified. Eight patients achieved complete remission (CR) with regional intra-arterial chemotherapy (RIAC), whereas no patients achieved CR with systemic chemotherapy. Compared with systemic chemotherapy, patients receiving RIAC had superior partial remissions (RR = 1.99, 95% CI: 1.50, 2.65; 58.06% with RIAC and 29.37% with systemic treatment), clinical benefits (RR = 2.34, 95% CI: 1.84, 2.97; 78.06% with RAIC and 29.37% with systemic treatment), total complication rates (RR = 0.72, 95% CI: 0.60, 0.87; 49.03% with RIAC and 71.33% with systemic treatment), and hematological side effects (RR = 0.76, 95% CI: 0.63, 0.91; 60.87% with RIAC and 85.71% with systemic treatment). The median survival time with RIAC (5-21 months) was longer than for systemic chemotherapy (2.7-14 months). Similarly, one year survival rates with RIAC (28.6%-41.2%) were higher than with systemic chemotherapy (0%-12.9%.). Regional intra-arterial chemotherapy is more effective and has fewer complications than systemic chemotherapy for treating advanced pancreatic cancer.

Hyper-connectivity of the Thalamus in during Early Stages following Mild Traumatic Brain Injury

PubMed Central

Sours, Chandler; George, Elijah O.; Zhuo, Jiachen; Roys, Steven; Gullapalli, Rao P.

2015-01-01

The thalamo-cortical resting state functional connectivity of 7 sub-thalamic regions were examined in a prospectively recruited population of 77 acute mild TBI (mTBI) patients within the first 10 days (mean 6±3 days) of injury and 35 neurologically intact control subjects using the Oxford thalamic connectivity atlas. Neuropsychological assessments were conducted using the Automated Neuropsychological Assessment Metrics (ANAM). A subset of participants received a magentic resonance spectroscopy (MRS) exam to determine metabolite concentrations in the thalamus and posterior cingulate cortex. Results show that patients performed worse than the control group on various subtests of ANAM and the weighted throughput score, suggesting reduced cognitive performance at this early stage of injury. Both voxel and region of interest based analysis of the resting state fMRI data demonstrated that acute mTBI patients have increased functional connectivity between the various sub-thalamic regions and cortical regions associated with sensory processing and the default mode network (DMN). In addition, a significant reduction in NAA/Cr was observed in the thalamus in the mTBI patients. Furthermore, an increase in Cho/Cr ratio specific to mTBI patients with self-reported sensory symptoms was observed compared to those without self-reported sensory symptoms. These results provide novel insights into the neural mechanisms of the brain state related to internal rumination and arousal, which have implications for new interventions for mTBI patients with persistent symptoms. Furthermore, an understanding of heightened sensitivity to sensory related inputs during early stages of injury may facilitate enhanced prediction of safe return to work. PMID:26153468

Do Cartilage Repair Procedures Prevent Degenerative Meniscus Changes? Longitudinal T1ρ and Morphological Evaluation at 3.0T

PubMed Central

Jungmann, Pia M.; Li, Xiaojuan; Nardo, Lorenzo; Subburaj, Karupppasamy; Lin, Wilson; Ma, C. Benjamin; Majumdar, Sharmila; Link, Thomas M.

2014-01-01

Background Cartilage repair (CR) procedures are widely accepted for treatment of isolated cartilage defects at the knee joint. However, it is not well known whether these procedures prevent degenerative joint disease. Hypothesis/Purpose CR procedures prevent accelerated qualitative and quantitative progression of meniscus degeneration in individuals with focal cartilage defects. Study Design Cohort Study; Level of evidence 2b Methods A total of 94 subjects were studied. CR procedures were performed on 34 patients (n=16 osteochondral transplantation, n=18 microfracture); 34 controls were matched. An additional 13 patients received CR and anterior cruciate ligament (ACL) reconstruction (CR&ACL) and 13 patients received only ACL reconstruction. 3.0T MRI with T1ρ mapping and sagittal fat-saturated intermediate-weighted fast spin echo (FSE) sequences was performed to analyze menisci quantitatively and qualitatively (Whole-Organ Magnetic Resonance Imaging Score, WORMS). CR and CR&ACL patients were examined 4 months (n=34; n=13), 1 (n=21; n=8) and 2 (n=9; n=5) years post CR. Control subjects were scanned at baseline and after 1 and 2 years, ACL patients after 1 and 2 years. Results At baseline, global meniscus T1ρ values were higher in individuals with CR (14.2±0.6ms; P=0.004) and in individuals with CR&ACL (17.1±0.9ms; P<0.001) when compared to controls (12.8±0.6ms). After two years, there was a statistical difference between T1ρ at the overlying meniscus above cartilage defects (16.4±1.0ms) and T1ρ of the subgroup of control knees without cartilage defects (12.1±0.8ms; P<0.001) and a statistical trend to the CR group (13.3±1.0 ms; P=0.088). At baseline, 35% of subjects with CR showed morphological meniscus tears at the overlying meniscus; 10% of CR subjects showed an increase of WORMS meniscus score within the first year, none progressed in the second year. Control subjects with (without) cartilage defects showed meniscus tears in 30% (5%) at baseline; 38% (19%) increased within the first, and 15% (10%) within the second year. Conclusions This study identified more severe meniscus degeneration after CR surgery compared to controls. However, progression of T1ρ values was not observed from 1 to 2 years after surgery. These results suggest, that CR may prevent degenerative meniscus changes. PMID:23104606

Electron energy loss spectroscopy analysis of lithium deintercalated Li5/3-xTi7/3CrO7

NASA Astrophysics Data System (ADS)

Díaz-Carrasco, P.; Moreau, P.; Guyomard, D.; Kuhn, A.; García-Alvarado, F.

2006-05-01

Electron energy loss spectroscopy has been used to investigate the average oxidation state of Cr in both electrochemically and chemically delithiathed Li5/3-xTi7/3CrO7. The O K edge, Ti L2,3 and Cr L2,3 edge were monitored. Upon removal of Li ions, the oxygen K edge shows a continuous change while the Cr L edges remain almost unchanged. The Cr 2p multiplet was compared with reference samples (Cr2O3, CrO2 and K2Cr2O7) in order to assess on the sensitivity of the Cr L-edge to the oxidation state of chromium ion. The similarity between the Cr L spectra of Cr2O3 and CrO2 makes the valence analysis difficult in Li5/3-xTi7/3CrO7 but the presence of CrVI is excluded in oxidized samples. However, evolution of the low energy loss spectra observed in the 10 15 eV region confirms the modification of the electronic structure and partial oxidation of CrIII to CrIV.

Distribution and transport of sediment-bound metal contaminants in the rio grande de tarcoles, costa rica (Central America)

USGS Publications Warehouse

Fuller, C.C.; Davis, J.A.; Cain, D.J.; Lamothe, P.J.; Fries Fernandez, T.L.G.; Vargas, J.A.; Murillo, M.M.

1990-01-01

A reconnaissance survey of the extent of metal contamination in the Rio Grande de Tarcoles river system of Costa Rica indicated high levels of chromium (Cr) in the fine-grain bed sediments (83 times Cr background or 3000->5000 ??g/g). In the main channel of the river downstream of the San Jose urban area, Cr contamination in sediments was 4-6 times background and remained relatively constant over 50 km to the mouth of the river. Sediment from a mangrove swamp at the river mouth had Cr levels 2-3 times above background. Similar patterns of dilution were observed for lead (Pb) and zinc (Zn) sediment contamination, although the contamination levels were lower. The high affinity of Cr towards particulate phases, probably as Cr(III), allows the use of Cr contamination levels for delineating regions of deposition of fine-grained sediments and dilution of particle associated contaminants during transport and deposition.A reconnaissance survey of the extent of metal contamination in the Rio Grande de Tarcoles river system of Costa Rica indicated high levels of chromium (Cr) in the fine-grain bed sediments (83 times Cr background or 3000->5000 ??g/g). In the main channel of the river downstream of the San Jose urban area, Cr contamination in sediments was 4-6 times background and remained relatively constant over 50 km to the mouth of the river. Sediments from a mangrove swamp at the river mouth had Cr levels 2-3 times above background. Similar patterns of dilution were observed for lead (Pb) and zinc (Zn) sediment contamination, although the contamination levels were lower. The high affinity of Cr towards particulate phases, probably as Cr(III), allows the use of Cr contamination levels for delineating regions of deposition of fine-grained sediments and dilution of particle associated contaminants during transport and deposition.

Increase of olfactory threshold in plating factory workers exposed to chromium in Korea.

PubMed

Kitamura, Fumihiko; Yokoyama, Kazuhito; Araki, Shunichi; Nishikitani, Mariko; Choi, Jae-Wook; Yum, Youg-Tae; Park, Hee-Chan; Park, Sang-Hwoi; Sato, Hajime

2003-07-01

To disclose the effects of chromium (Cr) on olfactory function, olfactory threshold tests were conducted on 27 male plating workers (Cr workers) with signs and symptoms of olfactory irritation but without nasal septum perforation or ulcer and on 34 male control subjects in Korean plating factories. The Cr workers had been exposed to Cr fume for 0.9 to 18.2 (mean 7.9) years; their blood Cr concentrations (0.16-3.69, mean 1.29 microg/dl) were significantly higher than those of the 34 control subjects (0.04-1.95, mean 0.55 microg/dl). Scores on recognition thresholds among the Cr workers were significantly higher than those of the control subjects (p < 0.05) and related positively and significantly to the exposure periods of the 27 Cr workers (p < 0.05). Olfactory thresholds were not significantly different between the Cr workers with and without nasal signs or symptoms, except that the scores on the recognition threshold were significantly higher in those experiencing difficulty with smell (p < 0.05). It is suggested that olfactory threshold is affected by Cr without development of nasal septum perforation or ulceration.

Implementing Cognitive Remediation Programs in France: The "Secret Sauce".

PubMed

Amado, Isabelle; Sederer, Lloyd I

2016-07-01

Cognitive remediation (CR) is a psychosocial therapy that seeks to restore patients' cognitive abilities by providing strategies to improve functioning in cognitive domains and helping them transfer acquired capabilities to everyday life. Since 2008, CR programs have been introduced in several regional health ministry areas in France. This column describes that implementation initiative, which includes creation of a network of the most active CR programs to conduct multicenter trials; establishment of a university degree in CR, awarded after completion of a one-year clinical training program; and implementation activities of regional health agencies. The authors describe three core elements of a "secret sauce"-a common language, timing, and leadership-that has helped ensure the success of the implementation efforts and that may be useful in other countries.

Supplementation with chromium picolinate recovers renal Cr concentration and improves carbohydrate metabolism and renal function in type 2 diabetic mice.

PubMed

Mita, Yukiko; Ishihara, Kengo; Fukuchi, Yoshiko; Fukuya, Yoko; Yasumoto, Kyoden

2005-01-01

To study the preventive effect of supplemented chromium picolinate (CrPic) on the development of diabetic nephropathy in mice, we analyzed the effects of CrPic supplementation on renal function and concentrations of serum glucose and tissue chromium (Cr). In experiment 1, male KK-Ay obese diabetic mice were fed either a control diet (control) or a diet supplemented with 2 mg/kg diet (Cr2) or 10 mg/kg diet (Cr10) of Cr for 12 wk. Cr10 significantly ameliorated hyperglycemia after a glucose load, creatinine clearance rates, and urinary microalbumin levels (p<0.05). In experiment 2, the Cr10 diet was fed to male KK-Ay obese diabetic mice and C57BL nondiabetic mice for 4 wk. The CrPic diet reduced urinary albumin excretion in the diabetic mice (p<0.05). Inductively coupled plasma-mass spectrometry analysis revealed that the renal Cr content and the recovery of renal Cr concentration after Cr supplementation were significantly lower in the diabetic mice than in the nondiabetic mice (p<0.01). These observations suggest that Cr supplementation of type 2 diabetic mice reduces the symptoms of hyperglycemia and improves the renal function by recovering renal Cr concentration.

Mindfulness and reduced cognitive reactivity to sad mood: evidence from a correlational study and a non-randomized waiting list controlled study.

PubMed

Raes, Filip; Dewulf, David; Van Heeringen, Cees; Williams, J Mark G

2009-07-01

Cognitive Reactivity (CR) refers to the degree to which a mild dysphoric state reactivates negative thinking patterns, and it has been found to play a key causal role in depressive relapse. Although Mindfulness-Based Cognitive Therapy (MBCT) directly aims to address this mechanism of CR, the relationship between mindfulness and CR has not been tested to date. Using a cross-sectional design (Study 1; n = 164) and a non-randomized waiting list controlled design (Study 2; MBCT [n = 18] vs. waiting list [n = 21]), the authors examined the relationship between naturally occurring levels of mindfulness (Study 1) and MBCT (Study 2) on the one hand, and CR on the other hand. In line with predictions, it was found that (a) trait mindfulness is significantly negatively correlated with CR, even when controlled for current depressive symptoms and prior history of depression (Study 1), and that (b) MBCT, compared to a matched control group, significantly reduces CR, and that this effect of MBCT on reduction of CR is mediated by a positive change in mindfulness skills (Study 2). Results provide first evidence for the claim that mindfulness practices in MBCT are designed to address the process of CR.

Speech effort measurement and stuttering: investigating the chorus reading effect.

PubMed

Ingham, Roger J; Warner, Allison; Byrd, Anne; Cotton, John

2006-06-01

The purpose of this study was to investigate chorus reading's (CR's) effect on speech effort during oral reading by adult stuttering speakers and control participants. The effect of a speech effort measurement highlighting strategy was also investigated. Twelve persistent stuttering (PS) adults and 12 normally fluent control participants completed 1-min base rate readings (BR-nonchorus) and CRs within a BR/CR/BR/CR/BR experimental design. Participants self-rated speech effort using a 9-point scale after each reading trial. Stuttering frequency, speech rate, and speech naturalness measures were also obtained. Instructions highlighting speech effort ratings during BR and CR phases were introduced after the first CR. CR improved speech effort ratings for the PS group, but the control group showed a reverse trend. Both groups' effort ratings were not significantly different during CR phases but were significantly poorer than the control group's effort ratings during BR phases. The highlighting strategy did not significantly change effort ratings. The findings show that CR will produce not only stutter-free and natural sounding speech but also reliable reductions in speech effort. However, these reductions do not reach effort levels equivalent to those achieved by normally fluent speakers, thereby conditioning its use as a gold standard of achievable normal fluency by PS speakers.

Distribution and contamination status of chromium in surface sediments of northern Kaohsiung Harbor, Taiwan.

PubMed

Dong, Cheng-Di; Chen, Chiu-Wen; Chen, Chih-Feng

2013-07-01

The distribution, enrichment, accumulation, and potential ecological risk of chromium (Cr) in the surface sediments of northern Kaohsiung Harbor, Taiwan, China were investigated. Sediment samples from ten locations located between the river mouths and harbor entrance of northern Kaohsiung Harbor were collected quarterly in 2011 and characterized for Cr, aluminum, water content, organic matter, total nitrogen, total phosphorous, total grease, and grain size. Results showed that the Cr concentrations varied from 27.0 to 361.9 mg/kg with an average of (113.5 +/- 87.0) mg/kg. High Cr concentration was observed near the Jen-Gen River mouth. The mean Cr concentration was high at 255.5 mg/kg, which was at least 2 to 7 times than that of other sites. This might imply significant Cr contribution from upstream receiving tanneries wastewater into the Jen-Gen River. The spatial distribution of Cr reveals relatively high in the river mouth region, especially in Jen-Gen River, and gradually diminishes toward the harbor entrance region. This indicates that the major sources of Cr pollution from upstream industrial and municipal wastewaters discharged along the river bank; and Cr may drift with sea current and be dispersed into open sea. Moreover, Cr concentrations correlated closely to the physical-chemical properties of the sediments, which suggested the influence of industrial and municipal wastewaters discharged from the neighboring industrial parks and river basins. Results from the enrichment factor and geo-accumulation index analyses imply that the Jen-Gen River sediments can be characterized as moderate enrichment and none to medium accumulation of Cr, respectively. However, results of potential ecological risk index indicate that the sediment has low ecological potential risk. The results can provide valuable information to developing future strategies for the management of river mouth and harbor.

Characterizing cosmic-ray propagation in massive star-forming regions: The case of 30 Doradus and the large Magellanic cloud

DOE PAGES

Murphy, E. J.; Porter, T. A.; Moskalenko, I. V.; ...

2012-04-24

We investigate the propagation characteristics of cosmic-ray (CR) electrons and nuclei in the 30 Doradus (30 Dor) star-forming region in the Large Magellanic Cloud (LMC) using infrared, radio, and γ-ray data and a phenomenological model based on the radio-far-infrared correlation within galaxies. By employing a correlation analysis, we derive an average propagation length of ~100-140 pc for ~3 GeV CR electrons resident in 30 Dor from consideration of the radio and infrared data. Assuming that the observed γ-ray emission toward 30 Dor is associated with the star-forming region, and applying the same methodology to the infrared and γ-ray data, wemore » estimate a ~20 GeV propagation length of 200-320 pc for the CR nuclei. This is approximately twice as large as for ~3 GeV CR electrons, corresponding to a spatial diffusion coefficient that is ~4 times higher, scaling as (R/GV) δ with δ ≈ 0.7-0.8 depending on the smearing kernel used in the correlation analysis. This value is in agreement with the results found by extending the correlation analysis to include ~70 GeV CR nuclei traced by the 3-10 GeV γ-ray data (δ ≈ 0.66 ± 0.23). Using the mean age of the stellar populations in 30 Dor and the results from our correlation analysis, we estimate a diffusion coefficient D R ≈ (0.9-1.0) × 10 27(R/GV) 0.7 cm 2 s –1. We also compare the values of the CR electron propagation length and surface brightness for 30 Dor and the LMC as a whole with those of entire disk galaxies. We find that the trend of decreasing average CR propagation distance with increasing disk-averaged star formation activity holds for the LMC, and extends down to single star-forming regions, at least for the case of 30 Dor.« less

Modelling in vivo creatine/phosphocreatine in vitro reveals divergent adaptations in human muscle mitochondrial respiratory control by ADP after acute and chronic exercise.

PubMed

Ydfors, Mia; Hughes, Meghan C; Laham, Robert; Schlattner, Uwe; Norrbom, Jessica; Perry, Christopher G R

2016-06-01

Mitochondrial respiratory sensitivity to ADP is thought to influence muscle fitness and is partly regulated by cytosolic-mitochondrial diffusion of ADP or phosphate shuttling via creatine/phosphocreatine (Cr/PCr) through mitochondrial creatine kinase (mtCK). Previous measurements of respiration in vitro with Cr (saturate mtCK) or without (ADP/ATP diffusion) show mixed responses of ADP sensitivity following acute exercise vs. less sensitivity after chronic exercise. In human muscle, modelling in vivo 'exercising' [Cr:PCr] during in vitro assessments revealed novel responses to exercise that differ from detections with or without Cr (±Cr). Acute exercise increased ADP sensitivity when measured without Cr but had no effect ±Cr or with +Cr:PCr, whereas chronic exercise increased sensitivity ±Cr but lowered sensitivity with +Cr:PCr despite increased markers of mitochondrial oxidative capacity. Controlling in vivo conditions during in vitro respiratory assessments reveals responses to exercise that differ from typical ±Cr comparisons and challenges our understanding of how exercise improves metabolic control in human muscle. Mitochondrial respiratory control by ADP (Kmapp ) is viewed as a critical regulator of muscle energy homeostasis. However, acute exercise increases, decreases or has no effect on Kmapp in human muscle, whereas chronic exercise surprisingly decreases sensitivity despite greater mitochondrial content. We hypothesized that modelling in vivo mitochondrial creatine kinase (mtCK)-dependent phosphate-shuttling conditions in vitro would reveal increased sensitivity (lower Kmapp ) after acute and chronic exercise. The Kmapp was determined in vitro with 20 mm Cr (+Cr), 0 mm Cr (-Cr) or 'in vivo exercising' 20 mm Cr/2.4 mm PCr (Cr:PCr) on vastus lateralis biopsies sampled from 11 men before, immediately after and 3 h after exercise on the first, fifth and ninth sessions over 3 weeks. Dynamic responses to acute exercise occurred throughout training, whereby the first session did not change Kmapp with in vivo Cr:PCr despite increases in -Cr. The fifth session decreased sensitivity with Cr:PCr or +Cr despite no change in -Cr. Chronic exercise increased sensitivity ±Cr in association with increased electron transport chain content (+33-62% complexes I-V), supporting classic proposals that link increased sensitivity to oxidative capacity. However, in vivo Cr:PCr reveals a perplexing decreased sensitivity, contrasting the increases seen ±Cr. Functional responses occurred without changes in fibre type or proteins regulating mitochondrial-cytosolic energy exchange (mtCK, VDAC and ANT). Despite the dynamic responses seen with ±Cr, modelling in vivo phosphate-shuttling conditions in vitro reveals that ADP sensitivity is unchanged after high-intensity exercise and is decreased after training. These findings challenge our understanding of how exercise regulates skeletal muscle energy homeostasis. © 2015 The Authors. The Journal of Physiology © 2015 The Physiological Society.

An assessment of the impact of ATMS and CrIS data assimilation on precipitation prediction over the Tibetan Plateau

NASA Astrophysics Data System (ADS)

Xue, Tong; Xu, Jianjun; Guan, Zhaoyong; Chen, Han-Ching; Chiu, Long S.; Shao, Min

2017-07-01

Using the National Oceanic and Atmospheric Administration's Gridpoint Statistical Interpolation data assimilation system and the National Center for Atmospheric Research's Advanced Research Weather Research and Forecasting (WRF-ARW) regional model, the impact of assimilating Advanced Technology Microwave Sounder (ATMS) and Cross-track Infrared Sounder (CrIS) satellite data on precipitation prediction over the Tibetan Plateau in July 2015 was evaluated. Four experiments were designed: a control experiment and three data assimilation experiments with different data sets injected: conventional data only, a combination of conventional and ATMS satellite data, and a combination of conventional and CrIS satellite data. The results showed that the monthly mean of precipitation is shifted northward in the simulations and showed an orographic bias described as an overestimation upwind of the mountains and an underestimation in the south of the rain belt. The rain shadow mainly influenced prediction of the quantity of precipitation, although the main rainfall pattern was well simulated. For the first 24 h and last 24 h of accumulated daily precipitation, the model generally overestimated the amount of precipitation, but it was underestimated in the heavy-rainfall periods of 3-5, 13-16, and 22-25 July. The observed water vapor conveyance from the southeastern Tibetan Plateau was larger than in the model simulations, which induced inaccuracies in the forecast of heavy rain on 3-5 July. The data assimilation experiments, particularly the ATMS assimilation, were closer to the observations for the heavy-rainfall process than the control. Overall, based on the experiments in July 2015, the satellite data assimilation improved to some extent the prediction of the precipitation pattern over the Tibetan Plateau, although the simulation of the rain belt without data assimilation shows the regional shifting.

Moderate caloric restriction in lactating rats programs their offspring for a better response to HF diet feeding in a sex-dependent manner.

PubMed

Palou, Mariona; Torrens, Juana María; Priego, Teresa; Sánchez, Juana; Palou, Andreu; Picó, Catalina

2011-06-01

We aimed to assess the lasting effects of moderate caloric restriction in lactating rats on the expression of key genes involved in energy balance of their adult offspring (CR) and their adaptations under high-fat (HF) diet. Dams were fed with either ad libitum normal-fat (NF) diet or a 30% caloric restricted diet throughout lactation. After weaning, the offspring were fed with NF diet until the age of 15 weeks and then with an NF or a HF diet until the age of 28 weeks, when they were sacrificed. Body weight and food intake were followed. Blood parameters and the expression of selected genes in hypothalamus and white adipose tissue (WAT) were analysed. CR ate fewer calories and showed lower body weight gain under HF diet than their controls. CR males were also resistant to the increase of insulin and leptin occurring in their controls under HF diet, and HF diet exposed CR females showed lower circulating fasting triglyceride levels than controls. In the hypothalamus, CR males had higher ObRb mRNA levels than controls, and CR females displayed greater InsR mRNA levels than controls and decreased neuropeptide Y mRNA levels when exposed to HF diet. CR males maintained WAT capacity of fat uptake and storage and of fatty-acid oxidation under HF diet, whereas these capacities were impaired in controls; female CR showed higher WAT ObRb mRNA levels than controls. These results suggest that 30% caloric restriction in lactating dams ameliorates diet-induced obesity in their offspring by enhancing their sensitivity to insulin and leptin signaling, but in a gender-dependent manner. Copyright © 2011 Elsevier Inc. All rights reserved.

Effects of chromium and chromium + vitamin C combination on metabolic, oxidative, and fear responses of broilers transported under summer conditions

NASA Astrophysics Data System (ADS)

Perai, A. H.; Kermanshahi, H.; Moghaddam, H. Nassiri; Zarban, A.

2015-04-01

A total of 240 female broilers (42 days old) were randomly assigned to four groups with six replicates and fed either a basal diet (two control groups) or a basal diet supplemented with either 1,200 μg Cr+3 from chromium (Cr) methionine/kg (Cr group) or 1,200 μg Cr+3 from Cr methionine plus 800 mg vitamin C (Vit C)/kg of diet (Cr + Vit C group). After 7 days on the dietary treatment, all groups except one of the controls were transported for 3 h under the summer conditions. Performance parameters were not influenced by dietary treatments. The plasma concentrations of insulin, triiodothyronine, triglyceride, and the ratio of triiodothyronine/thyroxin were decreased and the ratio of glucose/insulin was increased due to transport process. Road transportation also increased the plasma concentrations of protein, cholesterol, aspartate aminotransferase, and creatine kinase and decreased the concentration of low-density lipoprotein cholesterol in the Cr + Vit C group. The pretransport concentrations of insulin and triiodothyronine were highest in the Cr + Vit C group. The concentration of phosphorous was lower in the Cr group than that in the other groups after transport. No significant effects of dietary treatments were observed on the other biochemical parameters. Transport increased malondialdehyde concentration in the control group and did not change plasma total antioxidant capacity and erythrocyte glutathione peroxidase activity. Either in combination or alone, Cr increased plasma total antioxidant capacity (before transport P ≤ 0.05, after transport P = 0.07) but did not affect the concentration of malondialdehyde and activity of glutathione peroxidase. The duration of tonic immobility (TI) was similar between nontransported control chicks and transported chicks without any supplements. Pretreatment with Cr + Vit C significantly reduced the duration of TI.

Serial 1H-MRS in GM2 gangliosidoses.

PubMed

Assadi, Mitra; Baseman, Susan; Janson, Christopher; Wang, Dah-Jyuu; Bilaniuk, Larissa; Leone, Paola

2008-03-01

GM2 gangliosidoses are a group of neuronal storage disorders caused by deficiency in the lysosomal enzyme hexosaminidase A. Clinically, the disease is marked by a relentless encephalopathy. Proton magnetic resonance spectroscopy (1H-MRS) provides in-vivo measurement of various brain metabolites including N-acetyl aspartate+N-acetyl aspartate glutamate (NAA), myo-inositol (mI), choline (Cho) and creatine (Cr). The NAA represents neuronal integrity while elevation in the mI reflects abnormal inflammation and gliosis in the brain tissue. An elevation in the Cho levels suggest cell membrane breakdown and demyelination. We report the clinical and laboratory data in two patients with GM2 gangliosidoses. Serial 1H-MRS evaluations were performed to drive metabolite ratios of NAA/Cr, mI/Cr and Cho/Cr. We acquired the data from four regions of interest (ROI) according to a standard protocol. The results documented a progressive elevation in mI/Cr in all four ROI in patient one and only one ROI (occipital gray matter) in patient 2. We also documented a decline in the NAA/Cr ratios in both cases in most ROI. These results were compared to six age-matched controls and confirmed statistically significant elevation in the mI in our cases. In conclusion, 1H-MRS alterations were suggestive of neuronal loss and inflammation in these patients. 1H-MRS may be a valuable tool in monitoring the disease progress and response to therapy in GM2 gangliosidoses. Elevation in the mI may prove to be more sensitive than the other metabolite alterations.

Genetic variation and evolutionary demography of Fenneropenaeus chinensis populations, as revealed by the analysis of mitochondrial control region sequences

PubMed Central

2010-01-01

Genetic variation and evolutionary demography of the shrimp Fenneropenaeus chinensis were investigated using sequence data of the complete mitochondrial control region (CR). Fragments of 993 bp of the CR were sequenced for 93 individuals from five localities over most of the species' range in the Yellow Sea and the Bohai Sea. There were 84 variable sites defining 68 haplotypes. Haplotype diversity levels were very high (0.95 ± 0.03-0.99 ± 0.02) in F. chinensis populations, whereas those of nucleotide diversity were moderate to low (0.66 ± 0.36%-0.84 ± 0.46%). Analysis of molecular variance and conventional population statistics (FST ) revealed no significant genetic structure throughout the range of F. chinensis. Mismatch distribution, estimates of population parameters and neutrality tests revealed that the significant fluctuations and shallow coalescence of mtDNA genealogies observed were coincident with estimated demographic parameters and neutrality tests, in implying important past-population size fluctuations or range expansion. Isolation with Migration (IM) coalescence results suggest that F. chinensis, distributed along the coasts of northern China and the Korean Peninsula (about 1000 km apart), diverged recently, the estimated time-split being 12,800 (7,400-18,600) years ago. PMID:21637498

Proton magnetic resonance spectroscopy in ecstasy (MDMA) users.

PubMed

Daumann, Jörg; Fischermann, Thomas; Pilatus, Ulrich; Thron, Armin; Moeller-Hartmann, Walter; Gouzoulis-Mayfrank, Euphrosyne

2004-05-20

The popular recreational drug 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) has well-recognized neurotoxic effects upon central serotonergic systems in animal studies. In humans, the use of MDMA has been linked to cognitive problems, particularly to deficits in long-term memory and learning. Recent studies with proton magnetic resonance spectroscopy (1H MRS) have reported relatively low levels of the neuronal marker N-acetylaspartate (NAA) in MDMA users, however, these results have been ambiguous. Moreover, the only available 1H MRS study of the hippocampus reported normal findings in a small sample of five MDMA users. In the present study, we compared 13 polyvalent ecstasy users with 13 matched controls. We found no differences between the NAA/creatine/phosphocreatine (Cr) ratios of users and controls in neocortical regions, and only a tendency towards lower NAA/Cr ratios in the left hippocampus of MDMA users. Thus, compared with cognitive deficits, 1H MRS appears to be a less sensitive marker of potential neurotoxic damage in ecstasy users. Copyright 2004 Elsevier Ireland Ltd.

Measurement of urinary 11-dehydro-thromboxane B2 excretion in dogs with gastric dilatation-volvulus.

PubMed

Baltzer, Wendy I; McMichael, Maureen A; Ruaux, Craig G; Noaker, Laura; Steiner, Jörg M; Williams, David A

2006-01-01

To measure 11-dehydro-thromboxane B2 (11-dTXB2) in urine of healthy control dogs, dogs undergoing ovariohysterectomy, and dogs with gastric dilatation-volvulus (GDV) and assess the relationship between urinary 11-dTXB2 concentrations in dogs with GDV and postoperative outcomes. Urine samples from 15 nonsurgical control dogs, 12 surgical control dogs, and 32 dogs with GVD. Urine samples were obtained from healthy pet dogs (ie, nonsurgical control dogs), dogs undergoing ovariohysterectomy at anesthetic induction and 1 hour following surgery (ie, surgical control dogs), and dogs with GDV at hospital admission and 1 hour following surgical derotation of the stomach (ie, GDV dogs). Urinary 11-dTXB2 concentrations were determined with an ELISA and normalized to urinary creatinine (Cr) concentrations by calculation of the 11-dTXB2 -to-Cr ratio. Differences in median 11-dTXB2 -to-Cr ratios among dogs and before and after surgery were analyzed. Urinary 11-dTXB2-to-Cr ratios did not differ between nonsurgical control dogs and surgical control dogs before or after surgery. Urinary 11-dTXB2-to-Cr ratios were significantly higher in GDV dogs at the time of hospital admission and 1 hour after surgery, compared with those of nonsurgical control dogs. Postoperative urine samples from GDV dogs had significantly higher 11-dTXB2-to-Cr ratios than postoperative urine samples from surgical control dogs. Median urinary 11-dTXB2-to-Cr ratios increased significantly in GDV dogs that developed postoperative complications. Urinary 11-dTXB2 concentration is increased in GDV dogs at the time of hospital admission and after surgical derotation of the stomach, compared with that of healthy dogs. An increased urinary 11-dTXB2-to-Cr ratio following surgery is associated with an increased incidence of postoperative complications in dogs with GDV.

Metabolic networks in epilepsy by MR spectroscopic imaging.

PubMed

Pan, J W; Spencer, D D; Kuzniecky, R; Duckrow, R B; Hetherington, H; Spencer, S S

2012-12-01

The concept of an epileptic network has long been suggested from both animal and human studies of epilepsy. Based on the common observation that the MR spectroscopic imaging measure of NAA/Cr is sensitive to neuronal function and injury, we use this parameter to assess for the presence of a metabolic network in mesial temporal lobe epilepsy (MTLE) patients. A multivariate factor analysis is performed with controls and MTLE patients, using NAA/Cr measures from 12 loci: the bilateral hippocampi, thalami, basal ganglia, and insula. The factor analysis determines which and to what extent these loci are metabolically covarying. We extract two independent factors that explain the data's variability in control and MTLE patients. In controls, these factors characterize a 'thalamic' and 'dominant subcortical' function. The MTLE patients also exhibit a 'thalamic' factor, in addition to a second factor involving the ipsilateral insula and bilateral basal ganglia. These data suggest that MTLE patients demonstrate a metabolic network that involves the thalami, also seen in controls. The MTLE patients also display a second set of metabolically covarying regions that may be a manifestation of the epileptic network that characterizes limbic seizure propagation. © 2012 John Wiley & Sons A/S.

Proton MRS may predict AED response in patients with TLE.

PubMed

Campos, Bruno A G; Yasuda, Clarissa L; Castellano, Gabriela; Bilevicius, Elizabeth; Li, Li M; Cendes, Fernando

2010-05-01

To compare relative N-acetylaspartate (NAA) measurements in temporal lobe epilepsy (TLE) patients with good response to the first trial of antiepileptic drugs (AEDs) (an important prognostic factor) to TLE patients who failed the first AED monotherapy and required further AED trials with monotherapy or polytherapy. We studied 25 consecutive TLE patients who responded to first AED (responders) and 21 who did not (failure-group), as well as 27 controls. Patients were seen regularly in our Epilepsy Service and underwent electroencephalography (EEG) investigation, high-resolution magnetic resonance imaging (MRI), and single-voxel proton MR spectroscopy. Voxels were tailored to the medial temporal region on each side and involved the anterior hippocampus. Analysis of variance (ANOVA) demonstrated significant variation of NAA/creatine (NAA/Cr) values in both hippocampi, ipsilateral and contralateral to the EEG focus (p < 0.001 and p = 0.021) across the groups. Pairwise post hoc comparisons showed reduced NAA/Cr in both hippocampi of failure-group compared to controls (p < 0.001) and compared to responders (p < 0.05), but not between the controls and responders. Individual analyses showed NAA/Cr ratios lower than 2 SDs (standard deviations) below the mean of controls in 9 of 21 patients (42.8%) in the failure-group (6 with unilateral and 3 with bilateral reduction) but in none of the responders. These results indicate that patients with TLE who respond well to the first AED have significantly less evidence of neuronal and axonal damage/dysfunction compared to those who are refractory to the first AED trial.

Fasting urinary calcium-to-creatinine and oxalate-to-creatinine ratios in dogs with calcium oxalate urolithiasis and breed-matched controls.

PubMed

Furrow, E; Patterson, E E; Armstrong, P J; Osborne, C A; Lulich, J P

2015-01-01

Hypercalciuria and hyperoxaluria are risk factors for calcium oxalate (CaOx) urolithiasis, but breed-specific reports of urinary metabolites and their relationship with stone status are lacking. To compare urinary metabolites (calcium and oxalate) and blood ionized calcium (iCa) concentrations between CaOx stone formers and breed-matched stone-free controls for the Miniature Schnauzer, Bichon Frise, and Shih Tzu breeds. Forty-seven Miniature Schnauzers (23 cases and 24 controls), 27 Bichons Frise (14 cases and 13 controls), and 15 Shih Tzus (7 cases and 8 controls). Prospective study. Fasting spot urinary calcium-to-creatinine and oxalate-to-creatinine ratios (UCa/Cr and UOx/Cr, respectively) and blood iCa concentrations were measured and compared between cases and controls within and across breeds. Regression models were used to test the effect of patient and environmental factors on these variables. UCa/Cr was higher in cases than controls for each of the 3 breeds. In addition to stone status, being on a therapeutic food designed to prevent CaOx stone recurrence was associated with higher UCa/Cr. UOx/Cr did not differ between cases and controls for any of the breeds. Blood iCa was higher in cases than controls in the Miniature Schnauzer and Bichon Frise breeds and had a moderate correlation with UCa/Cr. Hypercalciuria is associated with CaOx stone status in the Miniature Schnauzer, Bichon Frise, and Shih Tzu breeds. UOx/Cr did not correlate with stone status in these 3 breeds. These findings may influence breed-specific stone prevention recommendations. Copyright © 2015 by the American College of Veterinary Internal Medicine.

Electric field control of ferromagnetism at room temperature in GaCrN (p-i-n) device structures

NASA Astrophysics Data System (ADS)

El-Masry, N. A.; Zavada, J. M.; Reynolds, J. G.; Reynolds, C. L.; Liu, Z.; Bedair, S. M.

2017-08-01

We have demonstrated a room temperature dilute magnetic semiconductor based on GaCrN epitaxial layers grown by metalorganic chemical vapor deposition. Saturation magnetization Ms increased when the GaCrN film is incorporated into a (p-GaN/i-GaCrN/n-GaN) device structure, due to the proximity of mediated holes present in the p-GaN layer. Zero field cooling and field cooling were measured to ascertain the absence of superparamagnetic behavior in the films. A (p-GaN/i-GaCrN/n-GaN) device structure with room temperature ferromagnetic (FM) properties that can be controlled by an external applied voltage has been fabricated. In this work, we show that the applied voltage controls the ferromagnetic properties, by biasing the (p-i-n) structure. With forward bias, ferromagnetism in the GaCrN layer was increased nearly 4 fold of the original value. Such an enhancement is due to carrier injection of holes into the Cr deep level present in the i-GaCrN layer. A "memory effect" for the FM behavior of the (p-i-n) GaCrN device structure persisted for 42 h after the voltage bias was turned off. These measurements also support that the observed ferromagnetism in the GaCrN film is not due to superparamagnetic clusters but instead is a hole-mediated phenomenon.

Paleomagnetic results from IODP Expedition 344 Site U1381 and implications for the initial subduction of the Cocos Ridge

NASA Astrophysics Data System (ADS)

Li, Yong-Xiang; Zhao, Xixi; Jovane, Luigi; Petronotis, Katerina; Gong, Zheng; Xie, Siyi

2016-04-01

Understanding the processes that govern the strength, nature, and distribution of slip along subduction zones is a fundamental and societally relevant goal of modern earth science. The Costa Rica Seismogenesis Project (CRISP) is specially designed to understand the processes that control nucleation and seismic rupture of large earthquakes at erosional subduction zones. Drilling directly on the Cocos Ridge (CR) during International Ocean Drilling Program (IODP) Expedition 344 discovered a sedimentary hiatus in Site U1381 cores. In this study, we conducted a magnetostratigraphic and rock magnetic study on the Cenozoic sedimentary sequences of site U1381. Anisotropy of magnetic susceptibility data from sediments above and below the hiatus show oblate fabrcis, but the Kmin axes of the AMS data from sediments below the hiatus are more dispersed than those from sediments above the hiatus, implying that formation of hiatus may have affected AMS. Paleomagnetic results of the U1381 core, together with available Ar-Ar dates of ash layers from sediments below the hiatus, allow us to establish a geomagnetic polarity timescale that brackets the hiatus between ca. 9.61 and 1.52 Ma. Analyses of sedimentary records from ODP/IODP cores in the vicinity reveal that the hiatus appears to be regional, spanning the northeastern end of the CR. Also, the hiatus appears to occur only at certain locations. Its regional occurrence at unique locations implies a link to the initial shallow subduction of the Cocos Ridge. The hiatus was probably produced by either bottom current erosion or the CR buckling upon its initial collision with the Middle American trench (MAT). Thus, the initial subduction of the CR must have taken place on or before 1.52 Ma.

Frontal Metabolite Concentration Deficits in Opiate Dependence Relate to Substance Use, Cognition, and Self-Regulation

PubMed Central

Murray, Donna E; Durazzo, Timothy C; Schmidt, Thomas P; Abé, Christoph; Guydish, Joseph; Meyerhoff, Dieter J

2016-01-01

Objective Proton magnetic resonance spectroscopy (1H MRS) in opiate dependence showed abnormalities in neuronal viability and glutamate concentration in the anterior cingulate cortex (ACC). Metabolite levels in dorsolateral prefrontal cortex (DLPFC) or orbitofrontal cortex (OFC) and their neuropsychological correlates have not been investigated in opiate dependence. Methods Single-volume proton MRS at 4 Tesla and neuropsychological testing were conducted in 21 opiate-dependent individuals (OD) on buprenorphine maintenance therapy. Results were compared to 28 controls (CON) and 35 alcohol-dependent individuals (ALC), commonly investigated treatment-seekers providing context for OD evaluation. Metabolite concentrations were measured from ACC, DLPFC, OFC and parieto-occipital cortical (POC) regions. Results Compared to CON, OD had lower concentrations of N-acetylaspartate (NAA), glutamate (Glu), creatine +phosphocreatine (Cr) and myo-Inositol (mI) in the DLPFC and lower NAA, Cr, and mI in the ACC. OD, ALC, and CON were equivalent on metabolite levels in the POC and γ-aminobutyric acid (GABA) concentration did not differ between groups in any region. In OD, prefrontal metabolite deficits in ACC Glu as well as DLPFC NAA and choline containing metabolites (Cho) correlated with poorer working memory, executive and visuospatial functioning; metabolite deficits in DLPFC Glu and ACC GABA and Cr correlated with substance use measures. In the OFC of OD, Glu and choline-containing metabolites were elevated and lower Cr concentration related to higher nonplanning impulsivity. Compared to 3 week abstinent ALC, OD had significant DLPFC metabolite deficits. Conclusion The anterior frontal metabolite profile of OD differed significantly from that of CON and ALC. The frontal lobe metabolite abnormalities in OD and their neuropsychological correlates may play a role in treatment outcome and could be explored as specific targets for improved OD treatment. PMID:27695638

Complete mitochondrial genome of Skylark, Alauda arvensis (Aves: Passeriformes): the first representative of the family Alaudidae with two extensive heteroplasmic control regions.

PubMed

Qian, Chaoju; Wang, Yuanxiu; Guo, Zhichun; Yang, Jianke; Kan, Xianzhao

2013-06-01

The circular mitochondrial genome of Alauda arvensis is 17,018 bp in length, containing 13 protein-coding genes (PCGs), 2 ribosomal RNA genes, 22 transfer RNA (tRNA) genes, and 2 extensive heteroplasmic control regions. All of the genes encoded on the H-strand, with the exceptions of one PCG (nad6) and eight tRNA genes (tRNA(Gln), tRNA(Ala), tRNA(Asn), tRNA(Cys), tRNA(Tyr), tRNA(Ser(UCN)), tRNA(Pro), and tRNA(Glu)), as found in other birds' mitochondrial genomes. All of these PCGs are initiated with ATG, while stopped by six types of stop codons. All tRNA genes have the potential to fold into typical clover-leaf structure. Two extensive heteroplasmic control regions were found, and more interestingly, a minisatellite of 37 nucleotides (5'-TCAATCCCATTGATTTCATTATATTAGTATAAAGAAA-3') with 6 tandem repeats was detected at the end of CR2.

Ultralow contact resistance at an epitaxial metal/oxide heterojunction through interstitial site doping.

PubMed

Chambers, Scott A; Gu, Meng; Sushko, Peter V; Yang, Hao; Wang, Chongmin; Browning, Nigel D

2013-08-07

Heteroepitaxial growth of Cr metal on Nb-doped SrTiO₃(001) is accompanied by Cr diffusion to interstitial sites within the first few atomic planes, an anchoring of the Cr film to the substrate, charge transfer from Cr to Ti, and metallization of the near-surface region, as depicted in the figure. The contact resistance of the resulting interface is exceedingly low. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The simultaneous detection of trivalent & hexavalent chromium in exhaled breath condensate: A feasibility study comparing workers and controls.

PubMed

Leese, Elizabeth; Morton, Jackie; Gardiner, Philip H E; Carolan, Vikki A

2017-04-01

The analytical method outlined in this feasibility study has been used to show that trivalent chromium (Cr(III)) and hexavalent chromium (Cr(VI)) can be detected and measured in exhaled breath condensate (EBC) samples. EBC samples and urine samples were collected from a cohort of 58 workers occupationally exposed to hexavalent chromium compounds and 22 unexposed volunteers (control group). Levels of Cr(III) and Cr(VI) were determined in EBC samples and total chromium levels were determined in urine samples. Pre and post working week samples for both EBC and urine were collected in tandem. Total chromium in urine samples was analysed by inductively coupled plasma mass spectrometry (ICP-MS). Analysis of Cr(III) and Cr(VI) in EBC samples used a hyphenated micro liquid chromatography (μLC) system coupled to an ICP-MS. Separation was achieved using an anion exchange micro-sized column. The results showed that the occupationally exposed workers had significantly higher levels of Cr(III) and Cr(VI) in their EBC samples than the control group, as well as higher levels of total chromium in their urine samples. However, for the exposed workers no significant difference was found between pre and post working week EBC samples for either Cr(III) or Cr(VI). This study has established that Cr(III) and Cr(VI) can simultaneously be detected and measured in 'real' EBC samples and will help in understanding inhalation exposure. Crown Copyright © 2016. Published by Elsevier GmbH. All rights reserved.

The effect of epileptic seizures on proton MRS visible neurochemical concentrations.

PubMed

Simister, Robert J; McLean, Mary A; Salmenpera, Tuuli M; Barker, Gareth J; Duncan, John S

2008-09-01

To investigate post-ictal changes in cerebral metabolites. We performed a longitudinal quantitative proton magnetic resonance spectroscopy (MRS) study in 10 patients with epilepsy and 10 control subjects. The patients were studied on two occasions: immediately following a seizure, and on a second occasion at least 7h after the most recent seizure. Each study measured N-acetyl aspartate plus N-acetyl aspartyl glutamate (NAAt), Creatine plus phosphocreatine (Cr), Choline containing compounds (Cho) and glutamate plus glutamine (GLX) concentrations using a short-echo time sequence (TE=30ms), and NAAt, Cr and lactate using a second sequence with longer echo time (TE=144ms). The control group was studied on two occasions using the same sequences. No inter-scan differences were observed for the control group. NAAt and NAAt/Cr levels were lower in the patient group at both measured TEs but did not change significantly between studies. The ratio of Cr at TE 144ms to TE 30ms (Cr(144)/Cr(30)) and GLX/Cr were higher and Cho lower in the post-ictal scan compared to the inter-ictal study. Change in Cr(144)/Cr(30) and NAAt(144)/Cr(144) correlated with the post-ictal interval. Lactate measurement at longer TE was not informative. Proton MRS is sensitive to metabolite changes following epileptic seizures within the immediate post-ictal period. The ratio Cr(144)/Cr(30) is the most sensitive measure of metabolic disturbance and is highest in the post-ictal period but appears to normalise within 2h of the most recent seizure.

Modeling actual evapotranspiration with routine meteorological variables in the data-scarce region of the Tibetan Plateau: Comparisons and implications

NASA Astrophysics Data System (ADS)

Ma, Ning; Zhang, Yinsheng; Xu, Chong-Yu; Szilagyi, Jozsef

2015-08-01

Quantitative estimation of actual evapotranspiration (ETa) by in situ measurements and mathematical modeling is a fundamental task for physical understanding of ETa as well as the feedback mechanisms between land and the ambient atmosphere. However, the ETa information in the Tibetan Plateau (TP) has been greatly impeded by the extremely sparse ground observation network in the region. Approaches for estimating ETa solely from routine meteorological variables are therefore important for investigating spatiotemporal variations of ETa in the data-scarce region of the TP. Motivated by this need, the complementary relationship (CR) and Penman-Monteith approaches were evaluated against in situ measurements of ETa on a daily basis in an alpine steppe region of the TP. The former includes the Nonlinear Complementary Relationship (Nonlinear-CR) as well as the Complementary Relationship Areal Evapotranspiration (CRAE) models, while the latter involves the Katerji-Perrier and the Todorovic models. Results indicate that the Nonlinear-CR, CRAE, and Katerji-Perrier models are all capable of efficiently simulating daily ETa, provided their parameter values were appropriately calibrated. The Katerji-Perrier model performed best since its site-specific parameters take the soil water status into account. The Nonlinear-CR model also performed well with the advantage of not requiring the user to choose between a symmetric and asymmetric CR. The CRAE model, even with a relatively low Nash-Sutcliffe efficiency (NSE) value, is also an acceptable approach in this data-scarce region as it does not need information of wind speed and ground surface conditions. In contrast, application of the Todorovic model was found to be inappropriate in the dry regions of the TP due to its significant overestimation of ETa as it neglects the effect of water stress on the bulk surface resistance. Sensitivity analysis of the parameter values demonstrated the relative importance of each parameter in the corresponding model. Overall, the Nonlinear-CR model is recommended in the absence of measured ETa for local calibration of the model parameter values.

Single-Session Transcranial Direct Current Stimulation Temporarily Improves Symptoms, Mood, and Self-Regulatory Control in Bulimia Nervosa: A Randomised Controlled Trial.

PubMed

Kekic, Maria; McClelland, Jessica; Bartholdy, Savani; Boysen, Elena; Musiat, Peter; Dalton, Bethan; Tiza, Meyzi; David, Anthony S; Campbell, Iain C; Schmidt, Ulrike

2017-01-01

Evidence suggests that pathological eating behaviours in bulimia nervosa (BN) are underpinned by alterations in reward processing and self-regulatory control, and by functional changes in neurocircuitry encompassing the dorsolateral prefrontal cortex (DLPFC). Manipulation of this region with transcranial direct current stimulation (tDCS) may therefore alleviate symptoms of the disorder. This double-blind sham-controlled proof-of-principle trial investigated the effects of bilateral tDCS over the DLPFC in adults with BN. Thirty-nine participants (two males) received three sessions of tDCS in a randomised and counterbalanced order: anode right/cathode left (AR/CL), anode left/cathode right (AL/CR), and sham. A battery of psychological/neurocognitive measures was completed before and after each session and the frequency of bulimic behaviours during the following 24-hours was recorded. AR/CL tDCS reduced eating disorder cognitions (indexed by the Mizes Eating Disorder Cognitions Questionnaire-Revised) when compared to AL/CR and sham tDCS. Both active conditions suppressed the self-reported urge to binge-eat and increased self-regulatory control during a temporal discounting task. Compared to sham stimulation, mood (assessed with the Profile of Mood States) improved after AR/CL but not AL/CR tDCS. Lastly, the three tDCS sessions had comparable effects on the wanting/liking of food and on bulimic behaviours during the 24 hours post-stimulation. These data suggest that single-session tDCS transiently improves symptoms of BN. They also help to elucidate possible mechanisms of action and highlight the importance of selecting the optimal electrode montage. Multi-session trials are needed to determine whether tDCS has potential for development as a treatment for adult BN.

Single-Session Transcranial Direct Current Stimulation Temporarily Improves Symptoms, Mood, and Self-Regulatory Control in Bulimia Nervosa: A Randomised Controlled Trial

PubMed Central

Kekic, Maria; McClelland, Jessica; Bartholdy, Savani; Boysen, Elena; Musiat, Peter; Dalton, Bethan; Tiza, Meyzi; David, Anthony S.; Campbell, Iain C.; Schmidt, Ulrike

2017-01-01

Background Evidence suggests that pathological eating behaviours in bulimia nervosa (BN) are underpinned by alterations in reward processing and self-regulatory control, and by functional changes in neurocircuitry encompassing the dorsolateral prefrontal cortex (DLPFC). Manipulation of this region with transcranial direct current stimulation (tDCS) may therefore alleviate symptoms of the disorder. Objective This double-blind sham-controlled proof-of-principle trial investigated the effects of bilateral tDCS over the DLPFC in adults with BN. Methods Thirty-nine participants (two males) received three sessions of tDCS in a randomised and counterbalanced order: anode right/cathode left (AR/CL), anode left/cathode right (AL/CR), and sham. A battery of psychological/neurocognitive measures was completed before and after each session and the frequency of bulimic behaviours during the following 24-hours was recorded. Results AR/CL tDCS reduced eating disorder cognitions (indexed by the Mizes Eating Disorder Cognitions Questionnaire-Revised) when compared to AL/CR and sham tDCS. Both active conditions suppressed the self-reported urge to binge-eat and increased self-regulatory control during a temporal discounting task. Compared to sham stimulation, mood (assessed with the Profile of Mood States) improved after AR/CL but not AL/CR tDCS. Lastly, the three tDCS sessions had comparable effects on the wanting/liking of food and on bulimic behaviours during the 24 hours post-stimulation. Conclusions These data suggest that single-session tDCS transiently improves symptoms of BN. They also help to elucidate possible mechanisms of action and highlight the importance of selecting the optimal electrode montage. Multi-session trials are needed to determine whether tDCS has potential for development as a treatment for adult BN. PMID:28121991

Laboratory investigations of the effects of nitrification-induced acidification on Cr cycling in vadose zone material partially derived from ultramafic rocks

USGS Publications Warehouse

Mills, Christopher T.; Goldhaber, Martin B.

2012-01-01

Sacramento Valley (California, USA) soils and sediments have high concentrations of Cr(III) because they are partially derived from ultramafic material. Some Cr(III) is oxidized to more toxic and mobile Cr(VI) by soil Mn oxides. Valley soils typically have neutral to alkaline pH at which Cr(III) is highly immobile. Much of the valley is under cultivation and is both fertilized and irrigated. A series of laboratory incubation experiments were conducted to assess how cultivation might impact Cr cycling in shallow vadose zone material from the valley. The first experiments employed low (7.1 mmol N per kg soil) and high (35 mmol N kg− 1) concentrations of applied (NH4)2SO4. Initially, Cr(VI) concentrations were up to 45 and 60% greater than controls in low and high incubations, respectively. After microbially-mediated oxidation of all NH4+, Cr(VI) concentrations dropped below control values. Increased nitrifying bacterial populations (estimated by measurement of phospholipid fatty acids) may have increased the Cr(VI) reduction capacity of the vadose zone material resulting in the observed decreases in Cr(VI). Another series of incubations employed vadose zone material from a different location to which low (45 meq kg− 1) and high (128 meq kg− 1) amounts of NH4Cl, KCl, and CaCl2 were applied. All treatments, except high concentration KCl, resulted in mean soil Cr(VI) concentrations that were greater than the control. High concentrations of water-leachable Ba2 + (mean 38 μmol kg− 1) in this treatment may have limited Cr(VI) solubility. A final set of incubations were amended with low (7.1 mmol N kg− 1) and high (35 mmol N kg− 1) concentrations of commercial liquid ammonium polyphosphate (APP) fertilizer which contained high concentrations of Cr(III). Soil Cr(VI) in the low APP incubations increased to a concentration of 1.8 μmol kg− 1 (5 × control) over 109 days suggesting that Cr(III) added with the APP fertilizer was more reactive than naturally-occurring soil Cr(III).

Hexavalent chromium exposure and control in welding tasks.

PubMed

Meeker, John D; Susi, Pam; Flynn, Michael R

2010-11-01

Studies of exposure to the lung carcinogen hexavalent chromium (CrVI) from welding tasks are limited, especially within the construction industry where overexposure may be common. In addition, despite the OSHA requirement that the use of engineering controls such as local exhaust ventilation (LEV) first be considered before relying on other strategies to reduce worker exposure to CrVI, data on the effectiveness of LEV to reduce CrVI exposures from welding are lacking. The goal of the present study was to characterize breathing zone air concentrations of CrVI during welding tasks and primary contributing factors in four datasets: (1) OSHA compliance data; (2) a publicly available database from The Welding Institute (TWI); (3) field survey data of construction welders collected by the Center for Construction Research and Training (CPWR); and (4) controlled welding trials conducted by CPWR to assess the effectiveness of a portable LEV unit to reduce CrVI exposure. In the OSHA (n = 181) and TWI (n = 124) datasets, which included very few samples from the construction industry, the OSHA permissible exposure level (PEL) for CrVI (5 μg/m(3)) was exceeded in 9% and 13% of samples, respectively. CrVI concentrations measured in the CPWR field surveys (n = 43) were considerably higher, and 25% of samples exceeded the PEL. In the TWI and CPWR datasets, base metal, welding process, and LEV use were important predictors of CrVI concentrations. Only weak-to-moderate correlations were found between total particulate matter and CrVI, suggesting that total particulate matter concentrations are not a good surrogate for CrVI exposure in retrospective studies. Finally, in the controlled welding trials, LEV reduced median CrVI concentrations by 68% (p = 0.02). In conclusion, overexposure to CrVI in stainless steel welding is likely widespread, especially in certain operations such as shielded metal arc welding, which is commonly used in construction. However, exposure could be substantially reduced with proper use of LEV.

Bond Strength of Gold Alloys Laser Welded to Cobalt-Chromium Alloy

PubMed Central

Watanabe, Ikuya; Wallace, Cameron

2008-01-01

The objective of this study was to investigate the joint properties between cast gold alloys and Co-Cr alloy laser-welded by Nd:YAG laser. Cast plates were fabricated from three types of gold alloys (Type IV, Type II and low-gold) and a Co-Cr alloy. Each gold alloy was laser-welded to Co-Cr using a dental laser-welding machine. Homogeneously-welded and non-welded control specimens were also prepared. Tensile testing was conducted and data were statistically analyzed using ANOVA. The homogeneously-welded groups showed inferior fracture load compared to corresponding control groups, except for Co-Cr. In the specimens welded heterogeneously to Co-Cr, Type IV was the greatest, followed by low-gold and Type II. There was no statistical difference (P<0.05) in fracture load between Type II control and that welded to Co-Cr. Higher elongations were obtained for Type II in all conditions, whereas the lowest elongation occurred for low-gold welded to Co-Cr. This study indicated that, of the three gold alloys tested, the Type IV gold alloy was the most suitable alloy for laser-welding to Co-Cr. PMID:19088892

Hippocampal metabolic dysfunction in juvenile myoclonic epilepsy: 3D multivoxel spectroscopy study.

PubMed

Ristić, Aleksandar J; Ostojić, Jelena; Kozić, Duško; Vojvodić, Nikola M; Popović, Ljubica M; Janković, Slavko; Baščarević, Vladimir; Sokić, Dragoslav V

2011-06-15

To investigate the metabolic differences in hippocampi of patients with juvenile myoclonic epilepsy (JME) and healthy controls using magnetic resonance spectroscopy (MRS). A 3D multivoxel SE 135 MRS study on 1.5 T scanner of both hippocampi was performed in 17 patients with JME and normal brain MRI and in 19 age and sex matched controls. Three dominant signals were measured: Choline (Cho), Creatine (tCr) and N-Acetylaspartate (NAA) and expressed as ratios of Cho:tCr, NAA:tCr, NAA:Cho and NAA:(Cho+tCr). Metabolite ratios in head, body and tail of each hippocampus in the JME group of patients were compared with ratios from corresponding structures in the control group. We found a significant difference in metabolite ratios of both hippocampi between the JME and the control groups. We detected significant differences of Cho:tCr in the head, NAA:tCr in the head, body and tail, NAA:Cho and NAA:(Cho+tCr) in the body and tail of the left hippocampus, and NAA:Cho and NAA:(Cho+tCr) in the body and tail of the right hippocampus. Although not previously recognized as a part of the epileptogenic network, our results suggest that the hippocampus, well recognized as a key player in focal epilepsies, may have a certain role in the pathogenesis of JME. Copyright © 2010. Published by Elsevier B.V.

Regional Variations in Composition of Cr-spinel Xenocrysts From Kimberlite

NASA Astrophysics Data System (ADS)

Schulze, D. J.

2001-05-01

Important information on the composition of the upper mantle can be obtained by studying mantle xenocrysts in kimberlite, especially in situations in which intact mantle xenoliths are rare to absent. Spinel-group minerals are especially useful as they can coexist with garnet or represent regions of the mantle shallower than garnet-facies rocks, and chromites can exist in rocks too Al-depleted to form garnet. Xenolith studies have shown that along most typical cratonic geothermal gradients, the maximum Cr/(Cr+Al) (cr#) of spinel coexisting with garnet is 0.88. Cr-spinels with cr# > 0.88 are from Al-depleted rocks or from assemblages in which Al is partitioned into another phase (e.g., metasomatic phlogopite). Approximately 2500 Cr-spinel xenocrysts from 36 kimberlites in southern Africa and North America have been analysed (and some published data used) and evaluated, primarily in terms of cr# and Fe2/(Fe2+Mg) (fe#). Differences from pipe to pipe within and between cratons reflect variations in geologic history and fertility/depletion, only some of which can be related to mantle age. Within southern Africa, pipe average values of spinel xenocryst cr# are highest on the Kaapvaal Craton (0.80-0.89) where fe# varies from 0.36 to 0.47. Suites from the craton margin (e.g., in Lesotho) indicate a less depleted mantle (cr# = 0.75-0.80), similar to those from the Zimbabwe Craton (Orapa and Letlhakane, cr# = 0.80-0.81). Jwaneng (Kaapvaal Craton) is similar to the Zimbabwe Craton pipes (cr# = 0.83). Off-craton South African suites (Kalkput and Rietfontein) have lower cr# (0.72-0.75). Most southern African suites contain a significant population of Cr-spinel with cr# > 0.88 (including off-craton Rietfontein) except Liqhobong on the craton margin in Lesotho. Cr-spinel suites from North American kimberlites are quite different, with most suites being significantly more aluminous than African populations. Most Kirkland Lake kimberlites on the Superior Craton have a very restricted fe# (0.41-0.43) at cr# values below those from Kaapvaal and Zimbabwe Cratons (0.67-0.78). Wyoming Craton kimberlites (Sloan and Kelsey Lake) also have aluminous spinel populations (cr# = 0.70-0.76). High-Cr spinel xenocrysts (cr# > 0.88) are common in Superior Craton populations but less abundant on the Wyoming Craton. Off-craton kimberlites (on Grenville basement) in Kentucky and Pennsylvania are much more aluminous (cr# = 0.62) and have almost no xenocrysts with cr# > 0.88. The general increase in fertility (lower cr# in spinel) from craton centre to margin to off-craton is confirmed, but Cr-spinel populations from all tectonic settings in North American kimberlites appear to be less depleted on average than their equivalents in southern Africa.

Effect of the patient education - Learning and Coping strategies - in cardiac rehabilitation on return to work at one year: a randomised controlled trial show (LC-REHAB).

PubMed

Bitsch, Birgitte Laier; Nielsen, Claus Vinther; Stapelfeldt, Christina Malmose; Lynggaard, Vibeke

2018-05-21

Personal resources are identified as important for the ability to return to work (RTW) for patients with ischaemic heart disease (IHD) or heart failure (HF) undergoing cardiac rehabilitation (CR). The patient education 'Learning and Coping' (LC) addresses personal resources through a pedagogical approach. This trial aimed to assess effect of adding LC strategies in CR compared to standard CR measured on RTW status at one-year follow-up after CR. In an open parallel randomised controlled trial, patients with IHD or HF were block-randomised in a 1:1 ratio to the LC arm (LC plus CR) or the control arm (CR alone) across three Danish hospital units. Eligible patients were aged 18 to ≤60 and had not left the labour market. The intervention was developed from an inductive pedagogical approach consisting of individual interviews and group based teaching by health professionals with experienced patients as co-educators. The control arm consisted of deductive teaching (standard CR). RTW status was derived from the Danish Register for Evaluation of Marginalisation (DREAM). Blinding was not possible. The effect was evaluated by logistic regression analysis and reported as crude and adjusted odds ratios (OR) with 95% confidence interval (CI). The population for the present analysis was N = 244 (LC arm: n = 119 versus control arm: n = 125). No difference in RTW status was found at one year across arms (LC arm: 64.7% versus control arm: 68.8%, adjusted odds ratio OR: 0.76, 95% CI: 0.43-1.31). Addition of LC strategies in CR showed no improvement in RTW at one year follow-up. www.clinicaltrials.gov identifier NCT01668394. First Posted: August 20, 2012.

The Oncoprotein Tax Binds the SRC-1-Interacting Domain of CBP/p300 To Mediate Transcriptional Activation

PubMed Central

Scoggin, Kirsten E. S.; Ulloa, Aida; Nyborg, Jennifer K.

2001-01-01

Oncogenesis associated with human T-cell leukemia virus (HTLV) infection is directly linked to the virally encoded transcription factor Tax. To activate HTLV-1 transcription Tax interacts with the cellular protein CREB and the pleiotropic coactivators CBP and p300. While extensively studied, the molecular mechanisms of Tax transcription function and coactivator utilization are not fully understood. Previous studies have focused on Tax binding to the KIX domain of CBP, as this was believed to be the key step in recruiting the coactivator to the HTLV-1 promoter. In this study, we identify a carboxy-terminal region of CBP (and p300) that strongly interacts with Tax and mediates Tax transcription function. Through deletion mutagenesis, we identify amino acids 2003 to 2212 of CBP, which we call carboxy-terminal region 2 (CR2), as the minimal region for Tax interaction. Interestingly, this domain corresponds to the steroid receptor coactivator 1 (SRC-1)-interacting domain of CBP. We show that a double point mutant targeted to one of the putative α-helical motifs in this domain significantly compromises the interaction with Tax. We also characterize the region of Tax responsible for interaction with CR2 and show that the previously identified transactivation domain of Tax (amino acids 312 to 319) participates in CR2 binding. This region of Tax corresponds to a consensus amphipathic helix, and single point mutations targeted to amino acids on the face of this helix abolish interaction with CR2 and dramatically reduce Tax transcription function. Finally, we demonstrate that Tax and SRC-1 bind to CR2 in a mutually exclusive fashion. Together, these studies identify a novel Tax-interacting site on CBP/p300 and extend our understanding of the molecular mechanism of Tax transactivation. PMID:11463834

Oxidation of Cr(III)-Fe(III) Mixed-phase Hydroxides by Chlorine: Implications on the Control of Hexavalent Chromium in Drinking Water.

PubMed

Chebeir, Michelle; Liu, Haizhou

2018-05-17

The occurrence of chromium (Cr) as an inorganic contaminant in drinking water is widely reported. One source of Cr is its accumulation in iron-containing corrosion scales of drinking water distribution systems as Cr(III)-Fe(III) hydroxide, i.e., FexCr(1-x)(OH)3(s), where x represents the Fe(III) molar content and typically varies between 0.25 and 0.75. This study investigated the kinetics of inadvertent hexavalent chromium Cr(VI) formation via the oxidation of FexCr(1-x)(OH)3(s) by chlorine as a residual disinfectant in drinking water, and examined the impacts of Fe(III) content and drinking water chemical parameters including pH, bromide and bicarbonate on the rate of Cr(VI) formation. Data showed that an increase in Fe(III) molar content resulted in a significant decrease in the stoichiometric Cr(VI) yield and the rate of Cr(VI) formation, mainly due to chlorine decay induced by Fe(III) surface sites. An increase in bicarbonate enhanced the rate of Cr(VI) formation, likely due to the formation of Fe(III)-carbonato surface complexes that slowed down the scavenging reaction with chlorine. The presence of bromide significantly accelerated the oxidation of FexCr(1-x)(OH)3(s) by chlorine, resulting from the catalytic effect of bromide acting as an electron shuttle. A higher solution pH between 6 and 8.5 slowed down the oxidation of Cr(III) by chlorine. These findings suggested that the oxidative conversion of chromium-containing iron corrosion products in drinking water distribution systems can lead to the occurrence of Cr(VI) at the tap, and the abundance of iron, and a careful control of pH, bicarbonate and bromide levels can assist the control of Cr(VI) formation.

(51Cr)EDTA intestinal permeability in children with cow's milk intolerance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schrander, J.J.; Unsalan-Hooyen, R.W.; Forget, P.P.

1990-02-01

Making use of ({sup 51}Cr)EDTA as a permeability marker, we measured intestinal permeability in a group of 20 children with proven cow's milk intolerance (CMI), a group of 17 children with similar complaints where CMI was excluded (sick controls), and a group of 12 control children. ({sup 51}Cr)EDTA test results (mean +/- SD) were 6.85 +/- 3.64%, 3.42 +/- 0.94%, and 2.61 +/- 0.67% in the group with CMI, the sick control, and the control group, respectively. When compared to both control groups, patients with cow's milk intolerance (CMI) showed a significantly increased small bowel permeability. We conclude that themore » ({sup 51}Cr)EDTA test can be helpful for the diagnosis of cow's milk intolerance.« less

Effects of in ovo feeding of creatine pyruvate on the hatchability, growth performance and energy status in embryos and broiler chickens.

PubMed

Zhao, M M; Gao, T; Zhang, L; Li, J L; Lv, P A; Yu, L L; Gao, F; Zhou, G H

2017-10-01

The effects of in ovo feeding (IOF) of creatine pyruvate (CrPyr) on the hatchability, growth performance and energy status of embryos and broilers (Arbor Acres) were investigated. Five treatments were arranged as non-injected treatment (Control), 0.6 ml physiological saline (0.75%) injected treatment (Saline), and IOF treatments injected with 0.6 ml physiological saline (0.75%) containing 3, 6 or 12 mg CrPyr (CrPyr3, CrPyr6 or CrPyr12) into the amnion per fertile egg on day 17.5 of incubation. After hatching, 80 male chicks from each treatment with similar weight close to the average BW of their pooled group were selected and randomly assigned into eight replicates of 10 chicks each. The results showed that the hatchability was not affected among groups, whereas the hatching weight of broilers in CrPyr12 was significantly higher than the control and saline groups (P0.05). Irrespective of dosage, the concentrations of creatine and phosphocreatine, and activities of creatine kinase in embryos were enhanced in CrPyr treatments at 19 E when compared with the control and saline groups (P<0.05). The activities of glucose-6-phosphatase in liver in CrPyr6 and CrPyr12 treatments were higher than the control and saline groups at 19 E (P<0.05). In conclusion, these results indicated that IOF of CrPyr, especially at the level of 12 mg/egg, could improve energy status of embryos and hatchlings, which was useful for enhancing hatching weight, BW and pectoral muscle weight until the end of the experiments at 21 days post-hatch in broilers.

Cognitive remediation for individuals with psychosis in a supported education setting: a randomized controlled trial.

PubMed

Kidd, Sean A; Kaur, Jaswant; Virdee, Gursharan; George, Tony P; McKenzie, Kwame; Herman, Yarissa

2014-08-01

Cognitive remediation (CR) has demonstrated good outcomes when paired with supported employment, however little is known about its effectiveness when integrated into a supported education program. This randomized controlled trial examined the effectiveness of integrating CR within a supported education program compared with supported education without CR. Thirty-seven students with psychosis were recruited into the study in the 2012 academic year. Academic functioning, cognition, self-esteem, and symptomatology were assessed at baseline, at 4months following the first academic term in which CR was provided, and at 8months assessing maintenance of gains. The treatment group demonstrated better retention in the academic program and a trend of improvement across a range of academic functional domains. While both treatment and control groups showed improvement in cognitive measures, the outcomes were not augmented by CR training. CR was also associated with significant and sustained improvements in self esteem. Further research, investigating specific intervention components is required to clarify the mixed findings regarding the effectiveness of CR in an education setting. Copyright © 2014 Elsevier B.V. All rights reserved.

Mineralogical determination and geo-chemical modeling of chromium release from AOD slag: Distribution and leachability aspects.

PubMed

Li, Junguo; Liu, Bao; Zeng, Yanan; Wang, Ziming

2017-01-01

AOD (argon oxygen decarburization) slag, which is the by-product of the stainless steel refining process, is a recyclable slag because of its high content of calcium and silicon. The leaching toxicity cannot be ignored in the recycling process because the slag contains a certain amount of Cr. In this study, the mineral analysis, batch leaching tests and thermodynamic and kinetic modeling by PHREEQC combined with FactSage software were performed to explore the influence of the dissolution of primary minerals and the precipitation of secondary minerals on the elution of Cr from AOD slag. The results indicated that the main minerals in the original AOD slag are larnite, merwinite, pyroxene and periclase. Cr was dispersed in the mineral phases mentioned above. The simulation of Cr leaching controlled by Cr(III)-hydroxide corresponded better to the batch leaching tests, while the Cr leaching controlled by chromite or double control was underestimated. Increasing the L/S ratio enhances the pH of the leachate and restrains the elution of Cr from the AOD slag. Copyright © 2016 Elsevier Ltd. All rights reserved.

A single-blind cross over study investigating the efficacy of standard and controlled release levodopa in combination with entacapone in the treatment of end-of-dose effect in people with Parkinson's disease.

PubMed

Iansek, R; Danoudis, M

2011-08-01

To determine the efficacy of standard levodopa combined with controlled release levodopa and entacapone in controlling end-of-dose symptoms in Parkinson's disease. A single-blind cross over design was used to compare the duration of action for three pharmacological combinations: standard levodopa (L/DDC); standard levodopa combined with entacapone (L/DDC/E); and standard levodopa combined with controlled release levodopa (CR) and entacapone (L/DDC/CR/E). Thirty two participants with wearing-off symptoms and inadequate symptom control with L/DDC/E had their optimum dose of L/DDC determined at base line. Entacapone was added to the optimal L/DDC dose and duration of action determined. Levodopa CR dosage was adjusted to match the optimal L/DDC dose for each participant. All participants were then trialed on L/DDC/CR/E and duration of response calculated. Timed Up and Go (TUG) times and magnitude of extra movements were recorded hourly throughout the day over several days to determine the optimum interval between doses for each combination. The UPDRS (Sections 2 and 3), PDQ39 and fatigue scale, the PDF-16, were recorded at base line and when dosage intervals had stabilized on L/DDC/CR/E. Duration of response was greatest with L/DDC/CR/E compared to L/DDC/E (p < 0.001) and number of daily doses were less on L/DDC/CR/E compared to L/DDC/E (p < 0.001). UPDRS, PDQ39 and fatigue scores also improved on L/DDC/CR/E compared to L/DDC (p < 0.001). Dyskinesia increased on L/DDC/CR/E (p = 0.001) however magnitude was mild. Combining standard levodopa and levodopa CR preparations with entacapone is an additional treatment strategy to manage motor fluctuations in advanced PD. Copyright © 2011 Elsevier Ltd. All rights reserved.

Chronic intermittent but not constant hypoxia decreases NAA/Cr ratios in neonatal mouse hippocampus and thalamus.

PubMed

Douglas, Robert M; Miyasaka, Naoyuki; Takahashi, Kan; Latuszek-Barrantes, Adrianna; Haddad, Gabriel G; Hetherington, Hoby P

2007-03-01

Chronic constant hypoxia (CCH) and chronic intermittent hypoxia (CIH) are known to have deleterious effects on the central nervous system. Because of the difference in the pattern of hypoxic exposure, it is possible that the pathological outcome would vary. The N-acetyl aspartate/creatine (NAA/Cr) ratio is a reliable marker of neuronal integrity, and this can be noninvasively measured by proton nuclear magnetic resonance spectroscopy. P2 CD1 mouse pups with their dams were exposed to either CCH, where the Fi(O(2)) was maintained at 11% continuously or to CIH, where the Fi(O(2)) was varied between 21 and 11% every 4 min. P30 mice exposed to intermittent hypoxia for 4 wk demonstrated a significant decrease in the NAA/Cr ratio in the hippocampus and thalamus, which was reversed by a subsequent exposure to 4 wk of normoxia. Meanwhile, mice exposed to 4 wk of constant hypoxia did not demonstrate any differences in their NAA/Cr ratios from controls in these brain regions. These results indicate that an intermittent pattern of hypoxic exposure may have a more adverse effect on neuronal function and integrity than a continuous one. The reversal of NAA/Cr levels to baseline during the return to normoxia indicates that therapeutic strategies targeted at alleviating the intermittent hypoxic stress in diseases, such as obstructive sleep apnea, have the potential for inducing significant neurocognitive recovery in these patients.

MR Spectroscopy to Distinguish between Supratentorial Intraventricular Subependymoma and Central Neurocytoma.

PubMed

Ueda, Fumiaki; Aburano, Hiroyuki; Ryu, Yasuji; Yoshie, Yuichi; Nakada, Mitsutoshi; Hayashi, Yutaka; Matsui, Osamu; Gabata, Toshifumi

2017-07-10

The purpose of this study was to discriminate supratentorial intraventricular subependymoma (SIS) from central neurocytoma (CNC) using magnetic resonance spectroscopy (MRS). Single-voxel proton MRS using a 1.5T or 3T MR scanner from five SISs, five CNCs, and normal controls were evaluated. They were examined using a point-resolved spectroscopy. Automatically calculated ratios comparing choline (Cho), N-acetylaspartate (NAA), myoinositol (MI), and/or glycine (Gly) to creatine (Cr) were determined. Evaluation of Cr to unsuppressed water (USW) was also performed. Mann-Whitney U test was carried out to test the significance of differences in the metabolite ratios. Detectability of lactate (Lac) and alanine (Ala) was evaluated. Although a statistically significant difference (P < 0.0001) was observed in Cho/Cr among SIS, control spectra, and CNC, no statistical difference was noted between SIS and control spectra (P = 0.11). Statistically significant differences were observed in NAA/Cr between SIS and CNC (P = 0.04) or control spectra (P < 0.0001). A statistically significant difference was observed in MI and/or Gly to Cr between SIS and control spectra (P = 0.03), and CNC and control spectra (P < 0.0006). There were no statistical differences between SIS and CNC for MI and/or Gly to Cr (P = 0.32). Significant statistical differences were found between SIS and control spectra (P < 0.0053), control spectra and CNC (P < 0.0016), and SIS and CNC (P < 0.0083) for Cr to USW. Lac inverted doublets were confirmed in two SISs. Triplets of Lac and Ala were detected in four spectra of CNC. The present study showed that MRS can be useful in discriminating SIS from CNC.

Annual changes and seasonal variations of Cr in Jiaozhou Bay

NASA Astrophysics Data System (ADS)

Yang, Dongfang; Haixia, Li; Zhang, Longlei; Li, Jiangmin; Nan, Nan

2017-04-01

Many bays have been polluted by Cr due to the rapid increasing of industry, hence understanding the temporal change trends and seasonal patterns is essential to pollution control and environmental remediation. Jiaozhou Bay is a semi-closed bay located in Shandong Province, China. This paper analyzed the annual changes and seasonal variations of Cr in Jiaozhou Bay in 1979-1983. Results showed that for annual changes, Cr contents were showing decreasing trend. For seasonal variations, Cr contents were in order of spring > summer > autumn. In generally, the pollution level of Cr contents in the early stage of China’s Reform and Opening-up was still low. These results were meaningful as basic information for pollution control and environmental remediation in this Bay.

Spectra of Cosmic Ray Electrons and Diffuse Gamma Rays with the Constraints of AMS-02 and HESS Data

NASA Astrophysics Data System (ADS)

Chen, Ding; Huang, Jing; Jin, Hong-Bo

2015-10-01

Recently, AMS-02 reported their results of cosmic ray (CR) observations. In addition to the AMS-02 data, we add HESS data to estimate the spectra of CR electrons and the diffuse gamma rays above TeV. In the conventional diffusion model, a global analysis is performed on the spectral features of CR electrons and the diffuse gamma rays by the GALRPOP package. The results show that the spectrum structure of the primary component of CR electrons cannot be fully reproduced by a simple power law and that the relevant break is around 100 GeV. At the 99% confidence level (C.L.) the injection indices above the break decrease from 2.54 to 2.35, but the ones below the break are only in the range of 2.746-2.751. The spectrum of CR electrons does not need to add TeV cutoff to also match the features of the HESS data. Based on the difference between the fluxes of CR electrons and their primary components, the predicted excess of CR positrons is consistent with the interpretation that these positrons originate from a pulsar or dark matter. In the analysis of the Galactic diffuse gamma rays with the indirect constraint of AMS-02 and HESS data, it is found that the fluxes of Galactic diffuse gamma rays are consistent with the GeV data of the Fermi-Large Area Telescope (LAT) in the high-latitude regions. The results indicate that inverse Compton scattering is the dominant component in the range of hundreds of GeV to tens of TeV, respectively from the high-latitude regions to the low ones, and in all of the regions of the Galaxy the flux of diffuse gamma rays is less than that of CR electrons at the energy scale of 20 TeV.

SPECTRA OF COSMIC RAY ELECTRONS AND DIFFUSE GAMMA RAYS WITH THE CONSTRAINTS OF AMS-02 AND HESS DATA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Ding; Jin, Hong-Bo; Huang, Jing, E-mail: hbjin@bao.ac.cn

2015-10-01

Recently, AMS-02 reported their results of cosmic ray (CR) observations. In addition to the AMS-02 data, we add HESS data to estimate the spectra of CR electrons and the diffuse gamma rays above TeV. In the conventional diffusion model, a global analysis is performed on the spectral features of CR electrons and the diffuse gamma rays by the GALRPOP package. The results show that the spectrum structure of the primary component of CR electrons cannot be fully reproduced by a simple power law and that the relevant break is around 100 GeV. At the 99% confidence level (C.L.) the injectionmore » indices above the break decrease from 2.54 to 2.35, but the ones below the break are only in the range of 2.746–2.751. The spectrum of CR electrons does not need to add TeV cutoff to also match the features of the HESS data. Based on the difference between the fluxes of CR electrons and their primary components, the predicted excess of CR positrons is consistent with the interpretation that these positrons originate from a pulsar or dark matter. In the analysis of the Galactic diffuse gamma rays with the indirect constraint of AMS-02 and HESS data, it is found that the fluxes of Galactic diffuse gamma rays are consistent with the GeV data of the Fermi-Large Area Telescope (LAT) in the high-latitude regions. The results indicate that inverse Compton scattering is the dominant component in the range of hundreds of GeV to tens of TeV, respectively from the high-latitude regions to the low ones, and in all of the regions of the Galaxy the flux of diffuse gamma rays is less than that of CR electrons at the energy scale of 20 TeV.« less

Nanometre-scale 3D defects in Cr2AlC thin films.

PubMed

Chen, Y T; Music, D; Shang, L; Mayer, J; Schneider, J M

2017-04-20

MAX-phase Cr 2 AlC containing thin films were synthesized by magnetron sputtering in an industrial system. Nanometre-scale 3D defects are observed near the boundary between regions of Cr 2 AlC and of the disordered solid solution (CrAl) x C y . Shrinkage of the Cr-Cr interplanar distance and elongation of the Cr-Al distance in the vicinity of the defects are detected using transmission electron microscopy. The here observed deformation surrounding the defects was described using density functional theory by comparing the DOS of bulk Cr 2 AlC with the DOS of a strained and unstrained Cr 2 AlC(0001) surface. From the partial density of states analysis, it can be learned that Cr-C bonds are stronger than Cr-Al bonds in bulk Cr 2 AlC. Upon Cr 2 AlC(0001) surface formation, both bonds are weakened. While the Cr-C bonds recover their bulk strength as Cr 2 AlC(0001) is strained, the Cr-Al bonds experience only a partial recovery, still being weaker than their bulk counterparts. Hence, the strain induced bond strengthening in Cr 2 AlC(0001) is larger for Cr d - C p bonds than for Cr d - Al p bonds. The here observed changes in bonding due to the formation of a strained surface are consistent with the experimentally observed elongation of the Cr-Al distance in the vicinity of nm-scale 3D defects in Cr 2 AlC thin films.

Microstructural and Electrochemical Evaluation of Fusion Welded Low-Nickel and 304 SS at Different Heat Input

NASA Astrophysics Data System (ADS)

Bansod, Ankur V.; Patil, Awanikumar P.; Moon, Abhijeet P.; Shukla, Sourabh

2017-12-01

The present research study investigates the effect of heat input using E 308 electrode (controlled by welding current, i.e., 70, 85 and 100 A) on microstructure, mechanical properties and corrosion behavior of low-nickel and 304 stainless steel (SS) weldments produced by shielded metal arc welding technique. SEM investigation shows that with the higher heat input, δ-ferrite content was reduced. Dendrite and inter-dendritic length is also reduced by lowering the heat input. For all the heat inputs, it is observed that δ-ferrite content was higher in 304 stainless steel (SS) as compared to that of low-nickel austenitic stainless steel (Cr-Mn SS). Considering the heat input for Cr-Mn SS, coarse grains were observed in the heat-affected zone region. For low heat input (LHI), tensile fracture surface has exhibited river-like pattern with dimple appearance. Corrosion studies show better pitting resistance for low heat input (LHI) samples due to higher δ-ferrite present in the weld region. Similarly, higher interphase corrosion resistance is observed in both the SS grades causing more dissolution in the LHI samples.

Caloric restriction impedes age-related decline of mitochondrial function and neuronal activity

PubMed Central

Lin, Ai-Ling; Coman, Daniel; Jiang, Lihong; Rothman, Douglas L; Hyder, Fahmeed

2014-01-01

Caloric restriction (CR) prolongs lifespan and retards many detrimental effects of aging, but its effect on brain mitochondrial function and neuronal activity—especially in healthy aging—remains unexplored. Here we measured rates of neuronal glucose oxidation and glutamate–glutamine neurotransmitter cycling in young control, old control (i.e., healthy aging), and old CR rats using in vivo nuclear magnetic resonance spectroscopy. We found that, compared with the young control, neuronal energy production and neurotransmission rates were significantly reduced in healthy aging, but were preserved in old CR rats. The results suggest that CR mitigated the age-related deceleration of brain physiology. PMID:24984898

Early initiation of post-sternotomy cardiac rehabilitation exercise training (SCAR): study protocol for a randomised controlled trial and economic evaluation

PubMed Central

Lobley, Grace; Worrall, Sandra; Powell, Richard; Kimani, Peter K; Banerjee, Prithwish; Barker, Thomas

2018-01-01

Introduction Current guidelines recommend abstinence from supervised cardiac rehabilitation (CR) exercise training for 6 weeks post-sternotomy. This practice is not based on empirical evidence, thus imposing potentially unnecessary activity restrictions. Delayed participation in CR exercise training promotes muscle atrophy, reduces cardiovascular fitness and prolongs recovery. Limited data suggest no detrimental effect of beginning CR exercise training as early as 2 weeks post-surgery, but randomised controlled trials are yet to confirm this. The purpose of this trial is to compare CR exercise training commenced early (2 weeks post-surgery) with current usual care (6 weeks post-surgery) with a view to informing future CR guidelines for patients recovering from sternotomy. Methods and analysis In this assessor-blind randomised controlled trial, 140 cardiac surgery patients, recovering from sternotomy, will be assigned to 8 weeks of twice-weekly supervised CR exercise training commencing at either 2 weeks (early CR) or 6 weeks (usual care CR) post-surgery. Usual care exercise training will adhere to current UK recommendations. Participants in the early CR group will undertake a highly individualised 2–3 week programme of functional mobility, strength and cardiovascular exercise before progressing to a usual care CR programme. Outcomes will be assessed at baseline (inpatient), pre-CR (2 or 6 weeks post-surgery), post-CR (10 or 14 weeks post-surgery) and 12 months. The primary outcome will be change in 6 min walk distance. Secondary outcomes will include measures of functional fitness, quality of life and cost-effectiveness. Ethics and dissemination Recruitment commenced on July 2017 and will complete by December 2019. Results will be disseminated via national governing bodies, scientific meetings and peer-reviewed journals. Trial registration number NCT03223558; Pre-results. PMID:29574443

Establishment of a reference value for chromium in the blood for biological monitoring among occupational chromium workers.

PubMed

Li, Ping; Li, Yang; Zhang, Ji; Yu, Shan-Fa; Wang, Zhi-Liang; Jia, Guang

2016-10-01

The concentration of chromium in the blood (CrB) has been confirmed as a biomarker for occupational chromium exposure, but its biological exposure indices (BEIs) are still unclear, so we collected data from the years 2006 and 2008 (Shandong Province, China) to analyze the relationship between the concentration of chromium in the air (CrA) of the workplaces and CrB to establish a reference value of CrB for biological monitoring of occupational workers. The levels of the indicators for nasal injury, kidney (β2 microglobulin (β2-MG)), and genetic damages (8-hydroxy-deoxyguanosine (8-OHdG) and micronucleus (MN)) were measured in all subjects of the year 2011 (Henan Province, China) to verify the protective effect in this reference value of CrB. Compared with the control groups, the concentrations of CrA and CrB in chromium exposed groups were significantly higher (P < 0.05). Positive correlations were found between CrA and CrB in chromium exposed groups (r 2006 = 0.60, r 2008 = 0.35) in the years 2006 and 2008. According to the occupational exposure limitation of CrA (50 μg/m(3), China), the reference value of CrB was recommended to 20 μg/L. The levels of nasal injury, β2-MG, 8-OhdG, and MN were not significantly different between the low chromium exposed group (CrB ≤ 20 μg/L) and the control group, while the levels of β2-MG, 8-OHdG, and MN were statistically different in the high chromium exposed group than that in the control group. This research proved that only in occupational workers, CrB could be used as a biomarker to show chromium exposure in the environment. The recommended reference value of CrB was 20 μg/L. © The Author(s) 2015.

Urinary Uric Acid/Creatinine Ratio - A Marker For Perinatal Asphyxia.

PubMed

Patel, Kinjal Prahaladbhai; Makadia, Mayur Goradhanbhai; Patel, Vishwal Indravardan; Nilayangode, Haridas Neelakandan; Nimbalkar, Somashekhar Marutirao

2017-01-01

Perinatal hypoxia is one of the leading causes of perinatal mortality in developing countries. Both apgar score and arterial blood pH predict the neonatal mortality in asphyxia. Apgar score alone does not predict neurologic outcome and as it is influenced by various factors. This study was conducted to evaluate the utility and sensitivity of urinary uric acid to creatinine ratio (UA/Cr ratio) in asphyxia diagnosis, compared to invasive Arterial Blood Gas (ABG) analysis. To assess the urinary uric acid/creatinine ratio as an additional marker for perinatal asphyxia compared with ABG analysis in apgar score monitoring. The present case control study was conducted at a teaching hospital in Central Gujarat. Data of 40 healthy newborns and 40 asphyxiated newborns were collected. In absence of regional estimates, a sample of size 39 was required to attain a power of 80% at 5% alpha (type I error) considering a moderate effect size of 0.65. (UA/Cr) ratio was measured from the spot urine sample collected during 24-72 hours of birth. Statistical analysis was performed by Independent t-test, Pearson's correlation coefficient (r) and Receiver Operating Characteristic (ROC) plots. The mean (UA/Cr ratio) (2.75±0.18 vs 1.78±0.23) is significantly higher in asphyxiated group than in the control group (p<0.0001). Urinary UA/Cr ratio had negative correlation with blood pH (r= -0.27, p=0.18), which was not significant (p>0.05). Urinary UA/Cr ratio with criterion of >2.3 had 100% sensitivity, 100% specificity with AUC of 1 (p<0.0001) had a better predictive value. Apgar score is usually reduced in neonates with congenital anomalies and premature neonates. Hence, it is preferable that the clinical diagnosis of asphyxia by apgar scores be supported by other investigations so that early decision can be taken about the level of care the baby needs. pH, lactates and base deficits change with establishment of respiration following resuscitation. However, pH, lactate, base deficit estimations are invasive and need rapid estimations. Non-invasive urinary UA/Cr ratio may be an answer to these issues as it easy, economical and equally efficient.

Chromium(III) release from chromium‐tanned leather elicits allergic contact dermatitis: a use test study

PubMed Central

Erfani, Behnaz; Matura, Mihály; Lidén, Carola

2018-01-01

Summary Background Chromium (Cr) is a common skin sensitizer. The use of Cr(VI) in leather is restricted in the EU, but that of Cr(III) is not. Objectives To assess whether prolonged exposure to Cr‐tanned leather with mainly Cr(III) release may elicit allergic contact dermatitis in Cr‐allergic individuals. Method Ten Cr‐allergic subjects and 22 controls were patch tested with serial dilutions of Cr(III) and Cr(VI), and with leather samples. They then conducted a use test with a Cr‐tanned and a Cr‐free leather bracelet over a period of 3 weeks, for 12 h per day. Cr deposited on the skin from the bracelets was measured in the controls, and the diphenylcarbazide test for Cr(VI) and extraction tests for Cr(III) and Cr(VI) were conducted for the different leathers. Results Four of 10 Cr‐allergic subjects developed positive reactions to the Cr‐tanned bracelet within 7–21 days, whereas only 1 of 10 had a positive patch test reaction to this leather. Cr released from the Cr‐tanned leather was most probably entirely Cr(III), with a quantifiable amount being deposited on the skin. Conclusions This study strongly suggests that prolonged and repeated exposure to Cr‐tanned leather with mainly Cr(III) release is capable of eliciting allergic contact dermatitis in Cr‐allergic individuals. PMID:29322530

Tobacco control and the reduction in smoking-related premature deaths in the United States, 1964-2012.

PubMed

Holford, Theodore R; Meza, Rafael; Warner, Kenneth E; Meernik, Clare; Jeon, Jihyoun; Moolgavkar, Suresh H; Levy, David T

2014-01-08

January 2014 marks the 50th anniversary of the first surgeon general's report on smoking and health. This seminal document inspired efforts by governments, nongovernmental organizations, and the private sector to reduce the toll of cigarette smoking through reduced initiation and increased cessation. To model reductions in smoking-related mortality associated with implementation of tobacco control since 1964. Smoking histories for individual birth cohorts that actually occurred and under likely scenarios had tobacco control never emerged were estimated. National mortality rates and mortality rate ratio estimates from analytical studies of the effect of smoking on mortality yielded death rates by smoking status. Actual smoking-related mortality from 1964 through 2012 was compared with estimated mortality under no tobacco control that included a likely scenario (primary counterfactual) and upper and lower bounds that would capture plausible alternatives. National Health Interview Surveys yielded cigarette smoking histories for the US adult population in 1964-2012. Number of premature deaths avoided and years of life saved were primary outcomes. Change in life expectancy at age 40 years associated with change in cigarette smoking exposure constituted another measure of overall health outcomes. In 1964-2012, an estimated 17.7 million deaths were related to smoking, an estimated 8.0 million (credible range [CR], 7.4-8.3 million, for the lower and upper tobacco control counterfactuals, respectively) fewer premature smoking-related deaths than what would have occurred under the alternatives and thus associated with tobacco control (5.3 million [CR, 4.8-5.5 million] men and 2.7 million [CR, 2.5-2.7 million] women). This resulted in an estimated 157 million years (CR, 139-165 million) of life saved, a mean of 19.6 years for each beneficiary (111 million [CR, 97-117 million] for men, 46 million [CR, 42-48 million] for women). During this time, estimated life expectancy at age 40 years increased 7.8 years for men and 5.4 years for women, of which tobacco control is associated with 2.3 years (CR, 1.8-2.5) (30% [CR, 23%-32%]) of the increase for men and 1.6 years (CR, 1.4-1.7) (29% [CR, 25%-32%]) for women. Tobacco control was estimated to be associated with avoidance of 8 million premature deaths and an estimated extended mean life span of 19 to 20 years. Although tobacco control represents an important public health achievement, efforts must continue to reduce the effect of smoking on the nation's death toll.

The effects of combined versus selective adrenergic blockade on left ventricular and systemic hemodynamics, myocardial substrate preference, and regional perfusion in conscious dogs with dilated cardiomyopathy.

PubMed

Nikolaidis, Lazaros A; Poornima, Indu; Parikh, Pratik; Magovern, Megan; Shen, You-Tang; Shannon, Richard P

2006-05-02

Given that adverse effects of chronic sympathetic activation are mediated by all three adrenergic receptor subtypes (beta1, beta2, alpha1), we examined the effects of standard doses of carvedilol and metoprolol succinate (metoprolol controlled release/extended release [CR/XL]) on hemodynamics, myocardial metabolism, and regional organ perfusion. Both beta1 selective and combined adrenergic blockade reduce morbidity and mortality in heart failure. Whether there are advantages of one class over the other remains controversial, even in the wake of the Carvedilol Or Metoprolol European Trial (COMET). Similarly, the mechanistic basis for the relative differences is incompletely understood. Thirty-three conscious, chronically instrumented dogs with pacing-induced (240 min(-1) for 4 weeks) dilated cardiomyopathy (DCM) were randomized to carvedilol (25 mg twice daily, Coreg, Glaxo Smith Kline, Research Triangle, North Carolina) or metoprolol succinate (100 mg qd, Toprol XL, Astra Zeneca, Wilmington, Delaware). Left ventricular and systemic hemodynamics, myocardial substrate uptake, and norepinephrine spillover were measured before and after three days of treatment. Regional (renal, hepatic, skeletal muscle) blood flows were measured using neutron-activated microspheres. Both agents had comparable heart rate effects. However, carvedilol-treated dogs showed significantly greater increases in stroke volume and cardiac output and decreases in left ventricular end-diastolic pressure and systemic vascular resistance. Carvedilol increased renal, hepatic, and skeletal muscle blood flow. Carvedilol increased myocardial glucose uptake and suppressed norepinephrine and glucagon. Carvedilol antagonized the response to exogenous norepinephrine to a greater extent than metoprolol CR/XL. At doses inducing comparable heart rate reductions, short-term treatment with carvedilol had superior hemodynamic and metabolic effects compared with metoprolol CR/XL. These data suggest important advantages of blocking all three adrenergic receptor subtypes in DCM.

Cerebral Oxygen Saturation to Guide Oxygen Delivery in Preterm Neonates for the Immediate Transition after Birth: A 2-Center Randomized Controlled Pilot Feasibility Trial.

PubMed

Pichler, Gerhard; Urlesberger, Berndt; Baik, Nariae; Schwaberger, Bernhard; Binder-Heschl, Corinna; Avian, Alexander; Pansy, Jasmin; Cheung, Po-Yin; Schmölzer, Georg Marcus

2016-03-01

To assess if monitoring of cerebral regional tissue oxygen saturation (crSO2) using near-infrared spectroscopy (NIRS) to guide respiratory and supplemental oxygen support reduces burden of cerebral hypoxia and hyperoxia in preterm neonates during resuscitation after birth. Preterm neonates <34(+0) weeks of gestation were included in a prospective randomized controlled pilot feasibility study at 2 tertiary level neonatal intensive care units. In a NIRS-visible group, crSO2 monitoring in addition to pulse oximetry was used to guide respiratory and supplemental oxygen support during the first 15 minutes after birth. In a NIRS-not-visible group, only pulse oximetry was used. The primary outcomes were burden of cerebral hypoxia (<10th percentile) or hyperoxia (>90th percentile) measured in %minutes crSO2 during the first 15 minutes after birth. Secondary outcomes were all cause of mortality and/or cerebral injury and neurologic outcome at term age. Allocation sequence was 1:1 with block-randomization of 30 preterm neonates at each site. In the NIRS-visible group burden of cerebral hypoxia in %minutes, crSO2 was halved, and the relative reduction was 55.4% (95% CI 37.6-73.2%; P = .028). Cerebral hyperoxia was observed in NIRS-visible group in 3 neonates with supplemental oxygen and in NIRS-not-visible group in 2. Cerebral injury rate and neurologic outcome at term age was similar in both groups. Two neonates died in the NIRS-not-visible group and none in the NIRS-visible group. No severe adverse reactions were observed. Reduction of burden of cerebral hypoxia during immediate transition and resuscitation after birth is feasible by crSO2 monitoring to guide respiratory and supplemental oxygen support. ClinicalTrials.gov: NCT02017691. Copyright © 2016 Elsevier Inc. All rights reserved.

Enhanced performance of hexavalent chromium reducing cathodes in the presence of Shewanella oneidensis MR-1 and lactate.

PubMed

Xafenias, Nikolaos; Zhang, Yue; Banks, Charles J

2013-05-07

Biocathodes for the reduction of the highly toxic hexavalent chromium (Cr(VI)) were investigated using Shewanella oneidensis MR-1 (MR-1) as a biocatalyst and performance was assessed in terms of current production and Cr(VI) reduction. Potentiostatically controlled experiments (-500 mV vs Ag/AgCl) showed that a mediatorless MR-1 biocathode started up under aerated conditions in the presence of lactate, received 5.5 and 1.7 times more electrons for Cr(VI) reduction over a 4 h operating period than controls without lactate and with lactate but without MR-1, respectively. Cr(VI) reduction was also enhanced, with a decrease in concentration over the 4 h operating period of 9 mg/L Cr(VI), compared to only 1 and 3 mg/L, respectively, in the controls. Riboflavin, an electron shuttle mediator naturally produced by MR-1, was also found to have a positive impact in potentiostatically controlled cathodes. Additionally, a microbial fuel cell (MFC) with MR-1 and lactate present in both anode and cathode produced a maximum current density of 32.5 mA/m(2) (1000 Ω external load) after receiving a 10 mg/L Cr(VI) addition in the cathode, and cathodic efficiency increased steadily over an 8 day operation period with successive Cr(VI) additions. In conclusion, effective and continuous Cr(VI) reduction with associated current production were achieved when MR-1 and lactate were both present in the biocathodes.

Sequential Leaching of Chromium Contaminated Sediments - A Study Characterizing Natural Attenuation

NASA Astrophysics Data System (ADS)

Musa, D.; Ding, M.; Beroff, S.; Rearick, M.; Perkins, G.; WoldeGabriel, G. W.; Ware, D.; Harris, R.; Kluk, E.; Katzman, D.; Reimus, P. W.; Heikoop, J. M.

2015-12-01

Natural attenuation is an important process in slowing down the transport of hexavalent chromium, Cr(VI), an anthropogenic environmental contaminant, either by adsorption of Cr(VI) to sediments, or by reduction to nontoxic trivalent chromium, Cr(III). The capacity and mechanism of attenuation is explored in this sequential leaching study of different particle size fractions of chromium contaminated sediments and similar uncontaminated sediments from the regional aquifer near Los Alamos, New Mexico. Using this leaching protocol each sediment sample is split in two: one half is leached three times using a 0.1 M sodium bicarbonate/carbonate solution, while the second half is leached three times using a 0.01 M nitric acid, followed by two consecutively increasing magnitudes of nitric acid concentrations. Based on the amphoteric nature of chromium, alkaline leaching is used to establish the amount of Cr(VI) sorbed on the sediment, whereas acid leaching is used to establish the amount of Cr(III). The weak acid is predicted to release the attenuated anthropogenic Cr(III), without affecting Cr-bearing minerals. The sequential, stronger, acid is anticipated to leach Cr(III)-incorporated in the minerals. The efficiency and validation of the sequential leaching method is assessed by comparing the leaching behavior of bentonite and biotite samples, with and without loaded Cr(VI). A 97% chromium mass balance of leached Cr(VI)-loaded bentonite and biotite proves the viability of this method for further use on leaching contaminated sediments. By comparing contaminated and uncontaminated sediment leachate results, of chromium and other major and trace elements, the signature of anthropogenic chromium is determined. Further mineralogical characterization of the sediments provides a quantitative measure of the natural attenuation capacity for chromium. Understanding these results is pertinent in delineating the optimal procedure for the remediation of Cr(VI) in the regional aquifer near Los Alamos.

Mass spectrometry analysis of etch products from CR-39 plastic irradiated by heavy ions

NASA Astrophysics Data System (ADS)

Kodaira, S.; Nanjo, D.; Kawashima, H.; Yasuda, N.; Konishi, T.; Kurano, M.; Kitamura, H.; Uchihori, Y.; Naka, S.; Ota, S.; Ideguchi, Y.; Hasebe, N.; Mori, Y.; Yamauchi, T.

2012-09-01

As a feasibility study, gas chromatography-mass spectrometry (GC-MS) and matrix-assisted laser desorption ionization-mass spectrometry (MALDI-MS) have been applied to analyze etch products of CR-39 plastic (one of the most frequently used solid states nuclear track detector) for the understanding of track formation and etching mechanisms by heavy ion irradiation. The etch products of irradiated CR-39 dissolved in sodium hydroxide solution (NaOH) contain radiation-induced fragments. For the GC-MS analysis, we found peaks of diethylene glycol (DEG) and a small but a definitive peak of ethylene glycol (EG) in the etch products from CR-39 irradiated by 60 MeV N ion beams. The etch products of unirradiated CR-39 showed a clear peak of DEG, but no other significant peaks were found. DEG is known to be released from the CR-39 molecule as a fragment by alkaline hydrolysis reaction of the polymer. We postulate that EG was formed as a result of the breaking of the ether bond (C-O-C) of the DEG part of the CR-39 polymer by the irradiation. The mass distribution of polyallylalcohol was obtained from the etch products from irradiated and unirradiated CR-39 samples by MALDI-MS analysis. Polyallylalcohol, with the repeating mass interval of m/z = 58 Da (dalton) between m/z = 800 and 3500, was expected to be produced from CR-39 by alkaline hydrolysis. We used IAA as a matrix to assist the ionization of organic analyte in MALDI-MS analysis and found that peaks from IAA covered mass spectrum in the lower m/z region making difficult to identify CR-39 fragment peaks which were also be seen in the same region. The mass spectrometry analysis using GC-MS and MALDI-MS will be powerful tools to investigate the radiation-induced polymeric fragments and helping to understand the track formation mechanism in CR-39 by heavy ions.

Deposition of chromium in aquatic ecosystem from effluents of handloom textile industries in Ranaghat-Fulia region of West Bengal, India.

PubMed

Sanyal, Tanmay; Kaviraj, Anilava; Saha, Subrata

2015-11-01

Accumulation of chromium (Cr) was determined in water, sediment, aquatic plants, invertebrates and fish in aquatic ecosystems receiving effluents from handloom textile industries in Ranaghat-Fulia region of West Bengal in India. Cr was determined in the samples by atomic absorption spectrophotometer and data were analyzed functionally by Genetic Algorithm to determine trend of depositions of Cr in the sediment and water. Area plot curve was used to represent accumulation of Cr in biota. The results indicate that the aquatic ecosystems receiving the effluents from handloom textile factories are heavily contaminated by Cr. The contamination is hardly reflected in the concentration of Cr in water, but sediment exhibits seasonal fluctuation in deposition of Cr, concentration reaching to as high as 451.0 μg g(-1) during the peak production period. There is a clear trend of gradual increase in the deposition of Cr in the sediment. Aquatic weed, insect and mollusk specimens collected from both closed water bodies (S1 & S2) and riverine resources (S3 & S4) showed high rate of accumulation of Cr. Maximum concentration of Cr was detected in roots of aquatic weeds (877.5 μg g(-1)). Fish specimens collected from the polluted sites (S3 & S4) of river Churni showed moderate to high concentration of Cr in different tissues. Maximum concentration was detected in the liver of Glossogobius giuris (679.7 μg g(-1)) during monsoon followed by gill of Mystus bleekeri (190.0 μg g(-1)) and gut of G. giuris (123.7 μg g(-1)) during summer. Eutropiichthys vacha showed moderately high concentration of Cr in different tissues (65-99 μg g(-1)) while Puntius sarana showed relatively low concentration of Cr (below detection limit to 18.0 μg g(-1)) in different tissues except in gill (64.4 μg g(-1)).

Deposition of chromium in aquatic ecosystem from effluents of handloom textile industries in Ranaghat–Fulia region of West Bengal, India

PubMed Central

Sanyal, Tanmay; Kaviraj, Anilava; Saha, Subrata

2014-01-01

Accumulation of chromium (Cr) was determined in water, sediment, aquatic plants, invertebrates and fish in aquatic ecosystems receiving effluents from handloom textile industries in Ranaghat–Fulia region of West Bengal in India. Cr was determined in the samples by atomic absorption spectrophotometer and data were analyzed functionally by Genetic Algorithm to determine trend of depositions of Cr in the sediment and water. Area plot curve was used to represent accumulation of Cr in biota. The results indicate that the aquatic ecosystems receiving the effluents from handloom textile factories are heavily contaminated by Cr. The contamination is hardly reflected in the concentration of Cr in water, but sediment exhibits seasonal fluctuation in deposition of Cr, concentration reaching to as high as 451.0 μg g−1 during the peak production period. There is a clear trend of gradual increase in the deposition of Cr in the sediment. Aquatic weed, insect and mollusk specimens collected from both closed water bodies (S1 & S2) and riverine resources (S3 & S4) showed high rate of accumulation of Cr. Maximum concentration of Cr was detected in roots of aquatic weeds (877.5 μg g−1). Fish specimens collected from the polluted sites (S3 & S4) of river Churni showed moderate to high concentration of Cr in different tissues. Maximum concentration was detected in the liver of Glossogobius giuris (679.7 μg g−1) during monsoon followed by gill of Mystus bleekeri (190.0 μg g−1) and gut of G. giuris (123.7 μg g−1) during summer. Eutropiichthys vacha showed moderately high concentration of Cr in different tissues (65–99 μg g−1) while Puntius sarana showed relatively low concentration of Cr (below detection limit to 18.0 μg g−1) in different tissues except in gill (64.4 μg g−1). PMID:26644938

The complete mitochondrial genome of the Japanese ornamental koi carp (Cyprinus carpio) and its implication for the history of koi.

PubMed

Mabuchi, Kohji; Song, Hayeun

2014-02-01

Complete mitochondrial genome (mitogenome) sequences were determined for two individuals of Japanese ornamental koi carp. Interestingly, the obtained mitogenomes (16,581 bp) were both completely identical to the recently reported mitogenome of Oujiang color carp from China. Control region (CR) sequences in DNA database demonstrated that more than half (65%) of the koi carp individuals so far reported had partial or complete CR sequences identical to those from Oujiang color carp. These results might suggest that the Japanese koi carp has been originated from Chinese Oujiang color carp, contrary to the belief in Japan that the koi carps have been developed directly from carp stocks in Japan. In any case, the present results emphasize the importance of analyzing Oujiang color carp when studying the origin of koi carp.

Metabolic and Behavioral Compensations in Response to Caloric Restriction: Implications for the Maintenance of Weight Loss

PubMed Central

Redman, Leanne M.; Heilbronn, Leonie K.; Martin, Corby K.; de Jonge, Lilian; Williamson, Donald A.; Delany, James P.; Ravussin, Eric

2009-01-01

Background Metabolic and behavioral adaptations to caloric restriction (CR) in free-living conditions have not yet been objectively measured. Methodology and Principal Findings Forty-eight (36.8±1.0 y), overweight (BMI 27.8±0.7 kg/m2) participants were randomized to four groups for 6-months; Control: energy intake at 100% of energy requirements; CR: 25% calorie restriction; CR+EX: 12.5% CR plus 12.5% increase in energy expenditure by structured exercise; LCD: low calorie diet (890 kcal/d) until 15% weight reduction followed by weight maintenance. Body composition (DXA) and total daily energy expenditure (TDEE) over 14-days by doubly labeled water (DLW) and activity related energy activity (AREE) were measured after 3 (M3) and 6 (M6) months of intervention. Weight changes at M6 were −1.0±1.1% (Control), −10.4±0.9% (CR), −10.0±0.8% (CR+EX) and −13.9±0.8% (LCD). At M3, absolute TDEE was significantly reduced in CR (−454±76 kcal/d) and LCD (−633±66 kcal/d) but not in CR+EX or controls. At M6 the reduction in TDEE remained lower than baseline in CR (−316±118 kcal/d) and LCD (−389±124 kcal/d) but reached significance only when CR and LCD were combined (−351±83 kcal/d). In response to caloric restriction (CR/LCD combined), TDEE adjusted for body composition, was significantly lower by −431±51 and −240±83 kcal/d at M3 and M6, respectively, indicating a metabolic adaptation. Likewise, physical activity (TDEE adjusted for sleeping metabolic rate) was significantly reduced from baseline at both time points. For control and CR+EX, adjusted TDEE (body composition or sleeping metabolic rate) was not changed at either M3 or M6. Conclusions For the first time we show that in free-living conditions, CR results in a metabolic adaptation and a behavioral adaptation with decreased physical activity levels. These data also suggest potential mechanisms by which CR causes large inter-individual variability in the rates of weight loss and how exercise may influence weight loss and weight loss maintenance. Trial Registration ClinicalTrials.gov NCT00099151 PMID:19198647

Worldwide Emerging Environmental Issues Affecting the U.S. Military

DTIC Science & Technology

2010-08-01

Brazil protecting non-Amazonian tropical forests . A summary of the consultations across the region are presented in the UNDP LAC Regional...North-American Environmental Integration……..13 6.6 World’s Humid Tropical Forests to Suffer Considerable Biodiversity Change by 2100….…13 6.7 Latin...35456&Cr=sanitation&Cr1 Item 2. Food Security Concerns Increase Around the World The Food Security Risk Index 2010 reveals that the countries most

H2S adsorption on chromium, chromia, and gold/chromia surfaces: Photoemission studies

NASA Astrophysics Data System (ADS)

Rodriguez, J. A.; Chaturvedi, S.; Kuhn, M.; van Ek, J.; Diebold, U.; Robbert, P. S.; Geisler, H.; Ventrice, C. A., Jr.

1997-12-01

The reaction of H2S with chromium, chromia, and Au/chromia films grown on a Pt(111) crystal has been investigated using synchrotron-based high-resolution photoemission spectroscopy. At 300 K, H2S completely decomposes on polycrystalline chromium producing a chemisorbed layer of S that attenuates the Cr 3d valence features. No evidence was found for the formation of CrSx species. The dissociation of H2S on Cr3O4 and Cr2O3 films at room temperature produces a decrease of 0.3-0.8 eV in the work function of the surface and significant binding-energy shifts (0.2-0.6 eV) in the Cr 3p core levels and Cr 3d features in the valence region. The rate of dissociation of H2S increases following the sequence: Cr2O3

Control of relative carrier-envelope phase slip in femtosecond Ti:sapphire and Cr:forsterite lasers.

PubMed

Kobayashi, Yohei; Torizuka, Kenji; Wei, Zhiyi

2003-05-01

We were able to control relative carrier-envelope phase slip among mode-locked Ti:sapphire and Cr:forsterite lasers by employing electronic feedback. The pulse timings of these lasers were passively synchronized with our crossing-beam technique. Since the optical-frequency ratio of Ti:sapphire and Cr:forsterite is approximately 3:2, we can observe the phase relation by superimposing the third harmonic of Cr:forsterite and the second harmonic of Ti:sapphire lasers in time and in space. The spectrum width of the locked beat note was less than 3 kHz, which corresponds to the controlled fluctuation of a cavity-length difference of less than 10 pm.

Calorie restriction inhibits relapse behaviour and preference for alcohol within a two-bottle free choice paradigm in the alcohol preferring (iP) rat.

PubMed

Guccione, Lisa; Djouma, Elvan; Penman, Jim; Paolini, Antonio G

2013-02-17

Among its many beneficial effects, calorie restriction (CR) has also been found to reduce anxiety related behavior in the rodent. With heightened levels of stress and anxiety implicated as a key precipitating factor of relapse and alcohol addiction, it was found that a 25% CR in addition to inducing anxiolytic effects also had the capacity to reduce intake of alcohol and inhibit relapse within a model of operant self-administration. The aim of this study was to investigate if a 25% CR would also display similar effects in a two-bottle free choice paradigm, whereby 24 h ad libitum access to both 10% ethanol and water is provided. All animals were initially tested on the elevated plus maze (EPM) and open field test prior to commencing the two-bottle free choice paradigm. Differences between control and CR25% animals demonstrated the anxiolytic effects of CR, with the CR25% group displaying greater percentage of open arm/total arm duration and open arm/total arm entries in the EPM. During the acquisition phase of the two-bottle free choice paradigm, CR25% animals showed a reduced intake of 10% ethanol in ml/kg, in comparison to the control group. Whilst control animals displayed a strong preference for 10% ethanol, the CR25% group consumed both 10% ethanol and water equally with no differences found in total fluid intake between groups. Similarly this was also the case following forced deprivation. In addition to reduced intake and lack of preference for 10% ethanol, CR 25% animals unlike controls failed to display a typical alcohol deprivation effect following abstinence. Taken collectively the results of this study suggest that CR may act as a protective factor against addiction and relapse in the alcohol preferring (iP) rat. In addition, given CR25% animals did not display a preference for 10% ethanol, results also suggest that CR may be altering the hedonic impact of ethanol within this group. Copyright © 2012 Elsevier Inc. All rights reserved.

Once daily controlled-release pregabalin in the treatment of patients with fibromyalgia: a phase III, double-blind, randomized withdrawal, placebo-controlled study.

PubMed

Arnold, Lesley M; Arsenault, Pierre; Huffman, Cynthia; Patrick, Jeffrey L; Messig, Michael; Chew, Marci L; Sanin, Luis; Scavone, Joseph M; Pauer, Lynne; Clair, Andrew G

2014-10-01

Safety and efficacy of a once daily controlled-released (CR) formulation of pregabalin was evaluated in patients with fibromyalgia using a placebo-controlled, randomized withdrawal design. This multicenter study included 6 week single-blind pregabalin CR treatment followed by 13 week double-blind treatment with placebo or pregabalin CR. The starting dose of 165 mg/day was escalated during the first 3 weeks, up to 495 mg/day based on efficacy and tolerability. Patients with ≥50% reduction in average daily pain score at the end of the single-blind phase were randomized to continue pregabalin CR at the optimized dose (330-495 mg/day) or to placebo. The primary endpoint was time to loss of therapeutic response (LTR), defined as <30% pain reduction relative to single-blind baseline or discontinuation owing to lack of efficacy or adverse event (AE). Secondary endpoints included measures of pain severity, global assessment, functional status, tiredness/fatigue, and sleep. ClinicalTrials.gov NCT01271933. A total of 441 patients entered the single-blind phase, and 63 were randomized to pregabalin CR and 58 to placebo. The median time to LTR (Kaplan-Meier analysis) was significantly longer in the pregabalin CR group than placebo (58 vs. 22 days, p = 0.02). By trial end, 34/63 (54.0%) pregabalin CR and 41/58 (70.7%) placebo patients experienced LTR. Significantly more patients reported 'benefit from treatment' (Benefit, Satisfaction, and Willingness to Continue Scale) in the pregabalin CR group; no other secondary endpoints were statistically significant. Most AEs were mild to moderate in severity (most frequent: dizziness, somnolence). The percentage of pregabalin CR patients discontinuing because of AEs was 12.2% and 4.8% in the single-blind and double-blind phases, respectively (placebo, 0%). Time to LTR was significantly longer with pregabalin CR versus placebo in fibromyalgia patients who initially showed improvement with pregabalin CR, indicating maintenance of response. Pregabalin CR was well tolerated in most patients. Generalizability may be limited by study duration and selective population.

Color record in self-monitoring of blood glucose improves glycemic control by better self-management.

PubMed

Nishimura, Akiko; Harashima, Shin-ichi; Honda, Ikumi; Shimizu, Yoshiyuki; Harada, Norio; Nagashima, Kazuaki; Hamasaki, Akihiro; Hosoda, Kiminori; Inagaki, Nobuya

2014-07-01

Color affects emotions, feelings, and behaviors. We hypothesized that color used in self-monitoring of blood glucose (SMBG) is helpful for patients to recognize and act on their glucose levels to improve glycemic control. Here, two color-indication methods, color record (CR) and color display (CD), were independently compared for their effects on glycemic control in less frequently insulin-treated type 2 diabetes. One hundred twenty outpatients were randomly allocated to four groups with 2×2 factorial design: CR or non-CR and CD or non-CD. Blood glucose levels were recorded in red or blue pencil in the CR arm, and a red or blue indicator light on the SMBG meter was lit in the CD arm, under hyperglycemia or hypoglycemia, respectively. The primary end point was difference in glycated hemoglobin (HbA1c) reduction in 24 weeks. Secondary end points were self-management performance change and psychological state change. HbA1c levels at 24 weeks were significantly decreased in the CR arm by -0.28% but were increased by 0.03% in the non-CR arm (P=0.044). In addition, diet and exercise scores were significantly improved in the CR arm compared with the non-CR arm. The exercise score showed significant improvement in the CD arm compared with the non-CD arm but without a significant difference in HbA1c reduction. Changes in psychological states were not altered between the arms. CR has a favorable effect on self-management performance without any influence on psychological stress, resulting in improved glycemic control in type 2 diabetes patients using less frequent insulin injection. Thus, active but not passive usage of color-indication methods by patients is important in successful SMBG.

Source apportionment of airborne particulates through receptor modeling: Indian scenario

NASA Astrophysics Data System (ADS)

Banerjee, Tirthankar; Murari, Vishnu; Kumar, Manish; Raju, M. P.

2015-10-01

Airborne particulate chemistry mostly governed by associated sources and apportionment of specific sources is extremely essential to delineate explicit control strategies. The present submission initially deals with the publications (1980s-2010s) of Indian origin which report regional heterogeneities of particulate concentrations with reference to associated species. Such meta-analyses clearly indicate the presence of reservoir of both primary and secondary aerosols in different geographical regions. Further, identification of specific signatory molecules for individual source category was also evaluated in terms of their scientific merit and repeatability. Source signatures mostly resemble international profile while, in selected cases lack appropriateness. In India, source apportionment (SA) of airborne particulates was initiated way back in 1985 through factor analysis, however, principal component analysis (PCA) shares a major proportion of applications (34%) followed by enrichment factor (EF, 27%), chemical mass balance (CMB, 15%) and positive matrix factorization (PMF, 9%). Mainstream SA analyses identify earth crust and road dust resuspensions (traced by Al, Ca, Fe, Na and Mg) as a principal source (6-73%) followed by vehicular emissions (traced by Fe, Cu, Pb, Cr, Ni, Mn, Ba and Zn; 5-65%), industrial emissions (traced by Co, Cr, Zn, V, Ni, Mn, Cd; 0-60%), fuel combustion (traced by K, NH4+, SO4-, As, Te, S, Mn; 4-42%), marine aerosols (traced by Na, Mg, K; 0-15%) and biomass/refuse burning (traced by Cd, V, K, Cr, As, TC, Na, K, NH4+, NO3-, OC; 1-42%). In most of the cases, temporal variations of individual source contribution for a specific geographic region exhibit radical heterogeneity possibly due to unscientific orientation of individual tracers for specific source and well exaggerated by methodological weakness, inappropriate sample size, implications of secondary aerosols and inadequate emission inventories. Conclusively, a number of challenging issues and specific recommendations have been included which need to be considered for a scientific apportionment of particulate sources in different geographical regions of India.

Surface morphological, electrical and transport properties of rapidly annealed double layers Ru/Cr Schottky structure on n-type InP

NASA Astrophysics Data System (ADS)

Shanthi Latha, K.; Rajagopal Reddy, V.

2017-07-01

The electrical and transport properties of a fabricated bilayer Ru/Cr/ n-InP Schottky diode (SD) have been investigated at different annealing temperatures. Atomic force microscopy results have showed that the overall surface morphology of the Ru/Cr/ n-InP SD is fairly smooth at elevated temperatures. High barrier height is achieved for the diode annealed at 300 °C compared to the as-deposited, annealed at 200 and 400 °C diodes. The series resistance and shunt resistance of the Ru/Cr/ n-InP SD are estimated by current-voltage method at different annealing temperatures. The barrier heights and series resistance are also determined by Cheung's and modified Norde functions. The interface state density of the Ru/Cr/ n-InP SD is found to be decreased after annealing at 300 °C and then slightly increased upon annealing at 400 °C. The difference between barrier heights obtained from current-voltage and capacitance-voltage is also discussed. Experimental results have showed that the Poole-Frenkel emission is found to be dominant in the lower bias region whereas Schottky emission is dominant in the higher bias region for the Ru/Cr/ n-InP SDs irrespective of annealing temperatures.

Chromium picolinate modulates serotonergic properties and carbohydrate metabolism in a rat model of diabetes.

PubMed

Komorowski, James R; Tuzcu, Mehmet; Sahin, Nurhan; Juturu, Vijaya; Orhan, Cemal; Ulas, Mustafa; Sahin, Kazim

2012-10-01

Chromium picolinate (CrPic) has shown both antidepressant and antidiabetic properties. In this study, the effects of CrPic on serotonergic properties and carbohydrate metabolism in diabetic rats were evaluated. Sixty male Sprague-Dawley rats were divided into four groups. (1) The control group received only standard diet (8 % fat). (2) The CrPic group was fed standard diet and CrPic (80 μg CrPic per kilogram body mass (b.m.)/day), for 10 weeks (microgram/kilogram b.m./day). (3) The HFD/STZ group fed a high-fat diet (HFD, 40 % fat) for 2 weeks and then received streptozotocin (STZ, 40 mg/kg, i.p.) (i.v.) HFD-STZ-CrPic group treated as the previous group and then were administered CrPic. CrPic administration to HFD/STZ-treated rats increased brain chromium levels and improved all measurements of carbohydrate metabolism and serotonergic properties (P<0.001). CrPic also significantly increased levels of insulin, tryptophan, and serotonin (P<0.001) in the serum and brain, and decreased cortisol levels in the serum (P<0.01). Except chromium levels, no significant effect of CrPic supplementation was detected on the overall measured parameters in the control group. CrPic administration was well tolerated without any adverse events. The results support the use of CrPic supplementation which improves serotonergic properties of brain in diabetes.

Acute effects and after-effects of acoustic coordinated reset neuromodulation in patients with chronic subjective tinnitus.

PubMed

Adamchic, Ilya; Toth, Timea; Hauptmann, Christian; Walger, Martin; Langguth, Berthold; Klingmann, Ingrid; Tass, Peter Alexander

2017-01-01

Chronic subjective tinnitus is an auditory phantom phenomenon characterized by abnormal neuronal synchrony in the central auditory system. As shown computationally, acoustic coordinated reset (CR) neuromodulation causes a long-lasting desynchronization of pathological synchrony by downregulating abnormal synaptic connectivity. In a previous proof of concept study acoustic CR neuromodulation, employing stimulation tone patterns tailored to the dominant tinnitus frequency, was compared to noisy CR-like stimulation, a CR version significantly detuned by sparing the tinnitus-related pitch range and including substantial random variability of the tone spacing on the frequency axis. Both stimulation protocols caused an acute relief as measured with visual analogue scale scores for tinnitus loudness (VAS-L) and annoyance (VAS-A) in the stimulation-ON condition (i.e. 15 min after stimulation onset), but only acoustic CR neuromodulation had sustained long-lasting therapeutic effects after 12 weeks of treatment as assessed with VAS-L, VAS-A scores and a tinnitus questionnaire (TQ) in the stimulation-OFF condition (i.e. with patients being off stimulation for at least 2.5 h). To understand the source of the long-lasting therapeutic effects, we here study whether acoustic CR neuromodulation has different electrophysiological effects on oscillatory brain activity as compared to noisy CR-like stimulation under stimulation-ON conditions and immediately after cessation of stimulation. To this end, we used a single-blind, single application, cross over design in 18 patients with chronic tonal subjective tinnitus and administered three different 16-minute stimulation protocols: acoustic CR neuromodulation, noisy CR-like stimulation and low frequency range (LFR) stimulation, a CR type stimulation with deliberately detuned pitch and repetition rate of stimulation tones, as control stimulation. We measured VAS-L and VAS-A scores together with spontaneous EEG activity pre-, during- and post-stimulation. Under stimulation-ON conditions acoustic CR neuromodulation and noisy CR-like stimulation had similar effects: a reduction of VAS-L and VAS-A scores together with a decrease of auditory delta power and an increase of auditory alpha and gamma power, without significant differences. In contrast, LFR stimulation had significantly weaker EEG effects and no significant clinical effects under stimulation-ON conditions. The distinguishing feature between acoustic CR neuromodulation and noisy CR-like stimulation were the electrophysiological after-effects. Acoustic CR neuromodulation caused the longest significant reduction of delta and gamma and increase of alpha power in the auditory cortex region. Noisy CR-like stimulation had weaker and LFR stimulation hardly any electrophysiological after-effects. This qualitative difference further supports the assertion that long-term effects of acoustic CR neuromodulation on tinnitus are mediated by a specific disruption of synchronous neural activity. Furthermore, our results indicate that acute electrophysiological after-effects might serve as a marker to further improve desynchronizing sound stimulation.

Heavy metal contamination status and source apportionment in sediments of Songhua River Harbin region, Northeast China.

PubMed

Li, Ning; Tian, Yu; Zhang, Jun; Zuo, Wei; Zhan, Wei; Zhang, Jian

2017-02-01

The Songhua River represents one of the seven major river systems in China. It flows through Harbin city with 66 km long, locating in the northern China with a longer winter time. This paper aimed to study concentration distributions, stability, risk assessment, and source apportionment of heavy metals including chromium (Cr), cadmium (Cd), lead (Pb), mercury (Hg), arsenic (As), copper (Cu), zinc (Zn), and nickel (Ni) in 11 selected sections of the Songhua River Harbin region. Results showed that Cr, Cd, Pb, Hg, and As exceeded their respective geochemical background values in sediments of most monitoring sections. Compared with other important rivers and lakes in China, Cr, Hg, Cd, and As pollutions in surface sediments were above medium level. Further analysis of chemical speciation indicated that Cr and As in surface sediments were relatively stable while Pb and Cd were easily bioavailable. Correlation analysis revealed sources of these metals except As might be identical. Pollution levels and ecological risks of heavy metals in surface sediments presented higher in the mainstream region (45° 47.0' N ~ 45° 53.3' N, 126° 37.0' E ~ 126° 42.1' E). Source apportionment found Hejiagou and Ashi River were the main contributors to metal pollution of this region. Thus, anthropogenic activities along the Hejiagou and Ashi River should be restricted in order to protect the Songhua River Harbin region from metal contamination.

The CrIIL reduction of [2Fe-2S] ferredoxins and site of attachment of CrIII using 1H NMR and site-directed mutagenesis.

PubMed

Im, S C; Worrall, J A; Liu, G; Aliverti, A; Zanetti, G; Luchinat, C; Bertini, I; Sykes, A G

2000-04-17

The recently reported NMR solution structure of FeIIIFeIII parsley FdI has made possible 2D NOESY NMR studies to determine the point of attachment of CrIIIL in FeIIIFeIII...CrIIIL. The latter Cr-modified product was obtained by reduction of FeIIIFeIII parsley and spinach FdI forms with [Cr(15-aneN4) (H2O)2]2+ (15-aneN4 = 1,4,8,12-tetraazacyclopentadecane), referred to here as CrIIL, followed by air oxidation and chromatographic purification. From a comparison of NMR cross-peak intensities of native and Cr-modified proteins, two surface sites designated A and B, giving large paramagnetic CrIIIL broadening of a number of amino acid peaks, have been identified. The effects at site A (residues 19-22, 27, and 30) are greater than those at site B (residues 92-94 and 96), which is on the opposite side of the protein. From metal (ICP-AES) and electrospray ionization mass spectrometry (EIMS) analyses on the Cr-modified protein, attachment of a single CrIIIL only is confirmed for both parsley and spinach FdI and FdII proteins. Electrostatic interaction of the 3+ CrIIIL center covalently attached to one protein molecule (charge approximately -18) with a second (like) molecule provides an explanation for the involvement of two regions. Thus for 3-4 mM FeIIIFeIII...CrIIIL solutions used in NMR studies (CrIIIL attached at A), broadening effects due to electrostatic interactions at B on a second molecule are observed. Experiments with the Cys18Ala spinach FdI variant have confirmed that the previously suggested Cys-18 at site A is not the site of CrIIIL attachment. Line broadening at Val-22 of A gives the largest effect, and CrIIIL attachment at one or more adjacent (conserved) acidic residues in this region is indicated. The ability of CrIIL to bind in some (parsley and spinach) but not all cases (Anabaena variabilis) suggests that intramolecular H-bonding of acidic residues at A is relevant. The parsley and spinach FeIIFeIII...CrIIIL products undergo a second stage of reduction with the formation of FeIIFeII...CrIIIL. However, the spinach Glu92Ala (site B) variant undergoes only the first stage of reduction, and it appears that Glu-92 is required for the second stage of reduction to occur. A sample of CrIIIL-modified parsley FeIIIFeIII Fd is fully active as an electron carrier in the NADPH-cytochrome c reductase reaction catalyzed by ferredoxin-NADP+ reductase.

Controlled exercise effects on chromium excretion of trained and untrained runners consuming a constant diet

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, R.A.; Bryden, N.A.; Polansky, M.M.

1986-03-05

To determine if degree of training effects urinary Cr losses, Cr excretion of 8 adult trained and 5 untrained runners was determined on rest days and following exercise at 90% of maximal oxygen uptake on a treadmill to exhaustion with 30 second exercise and 30 second rest periods. Subjects were fed a constant daily diet containing 9 ..mu..g of Cr per 1000 calories to minimize changes due to diet. Maximal oxygen consumption of the trained runners was in the good or above range based upon their age and that of the untrained runners was average or below. While consuming themore » control diet, basal urinary Cr excretion of subjects who exercise regularly was significantly lower than that of the sedentary control subjects, 0.09 +/- 0.01 and 0.21 +/- 0.03 ..mu..g/day (mean +/- SEM), respectively. Daily urinary Cr excretion of trained subjects was significantly higher on the day of a single exercise bout at 90% of maximal oxygen consumption compared to nonexercise days, 0.12 +/- 0.02 and 0.09 +/- 0.01 ..mu..g/day, respectively. Urinary Cr excretion of 5 untrained subjects was not altered following controlled exercise. These data demonstrate that basal urinary Cr excretion and excretion in response to exercise are related to maximal oxygen consumption and therefore degree of fitness.« less

Assessment of phase constitution on the Al-rich region of rapidly solidified Al-Co-Fe-Cr alloys

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wolf, W., E-mail: witorw@gmail.com

The formation of quasicrystalline approximants in rapidly solidified Al-Co-Fe-Cr alloys was investigated. Alloys of atomic composition Al{sub 71}Co{sub 13}Fe{sub 8}Cr{sub 8}, Al{sub 77}Co{sub 11}Fe{sub 6}Cr{sub 6} and Al{sub 76}Co{sub 19}Fe{sub 4}Cr{sub 1} were produced using melt spinning and arc melting methods and their microstructural characterization was carried out by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. Up to the present there is no consensus in the literature regarding the formation of quasicrystalline phase or quasicrystalline approximants in the Al{sub 71}Co{sub 13}Fe{sub 8}Cr{sub 8} alloy. This work presents, for the first time, a detailed structural characterization of selected alloysmore » in the Al-Co-Fe-Cr system close to the atomic composition Al{sub 71}Co{sub 13}Fe{sub 8}Cr{sub 8}. The results indicated the samples to be composed, mostly, by two intermetallic phases, which are quaternary extensions of Al{sub 5}Co{sub 2} and Al{sub 13}Co{sub 4} and are quasicrystalline approximants. Although the Al{sub 5}Co{sub 2} phase has already been reported in the Al{sub 71}Co{sub 13}Fe{sub 8}Cr{sub 8} alloy, the presence of the monoclinic Al{sub 13}Co{sub 4} is now identified for the first time in the as cast state. In the binary Al-Co system a quasicrystalline phase is known to form in a rapidly solidified alloy with composition close to the monoclinic and orthorhombic Al{sub 13}Co{sub 4} phases. This binary quasicrystalline phase presents an average valence electron per atom (e/a) between 1.7 and 1.9; thus, in addition to the Al{sub 71}Co{sub 13}Fe{sub 8}Cr{sub 8} alloy, the compositions Al{sub 77}Co{sub 11}Fe{sub 6}Cr{sub 6} and Al{sub 76}Co{sub 19}Fe{sub 4}Cr{sub 1} were chosen to be within the region of formation of the quaternary extension of the Al{sub 13}Co{sub 4} phase and also within the (e/a) of 1.7 to 1.9. However, no quasicrystalline phase is present in any of the studied alloys. The Al-Co-Fe-Cr system, around the compositions studied, is composed of quaternary extensions of Al-Co intermetallic phases, which present solubility of Fe and Cr at Co atomic sites. - Highlights: •The Al rich region of the AlCoFeCr system is studied concerning phase formation on rapidly solidified alloys. •The alloys were composed mostly by quaternary extensions of Al-Co intermetallic phases. •Al{sub 5}Co{sub 2} and Al{sub 13}Co{sub 4} were the major phases observed in the alloys and are approximants of a quasicrystalline phase. •No quasicrystalline phase was observed in the Al{sub 71}Co{sub 13}Fe{sub 8}Cr{sub 8} composition.« less

Vegetative and Atmospheric Controls on the Bouchet-Morton Complementary Relationship Hypothesis

NASA Astrophysics Data System (ADS)

Pettijohn, J. C.; Salvucci, G. D.; Phillips, N. G.; Daley, M. J.

2006-12-01

The Bouchet-Morton Complementary Relationship (CR) hypothesis is a potentially-powerful analytic tool to help understand the feedback between evapotranspiring land surfaces and the atmospheric boundary layer (ABL), and how potential evaporation reflects this coupling on multiple time and length scales. In spite of advances in our ability to measure and model these processes, the heuristic CR hypothesis remains an unsolved, first-order problem. The leading theoretical models, i.e., Morton, Granger, and Szilagyi, of the coupled land surface atmosphere mechanisms responsible for CR focus primarily on vertical humidity (vapor pressure) profiles while assuming that vegetative and/or atmospheric diffusivities play an insignificant role in regulating CR. Further, whereas Granger and Szilagyi assume almost opposite vertical temperature profile boundary conditions, both derivations appear to validate CR. Contrary to these multiple working hypotheses' assumptions, our recent CR evaluation of 147 days (1987-1989) at the FIFE temperate grassland discovered that canopy conductance was an essential forcing variable in complementarity, and thus improved CR in application when included in the definition of potential evaporation. To isolate the exact forcing mechanisms of canopy and ABL conductances to complementarity, we evaluated CR in a mixed-deciduous forest at Harvard Forest (summers 2005-2006) by comparing daily averaged water-stressed (non-irrigated, regionally stressed soil moisture) and water-unstressed (irrigated, `potential') transpiration. Root-zone soil moisture of a red maple (Acer rubrum L.) sample set was elevated using a pulse-irrigation system. Whole-tree transpiration of the `potential` (water-unstressed) and a reference (water-stressed) set of maples was monitored at high frequency using heat-dissipation Granier-type sap flux sensors. To isolate physiological and/or atmospheric forcing of CR, we estimated isothermal Penman-Monteith transpiration models of both irrigated and non-irrigated time series using a Jarvis type multiplicative stress model of scaled canopy conductance to water vapor transport. Poorly-constrained model parameters (e.g., environmental stress boundary conditions) were estimated using a grid search routine; further, parameter confidence limits were inferred using bootstrap replacement sampling. Preliminary results suggest the following: (1) the absence of an unstressed canopy conductance in the Penman equation results in violation of fundamental CR assumptions (similar to FIFE); and (2) unlimited root-zone water availability does not reduce the leaf-level stomatal resistance enough to yield complementarity, i.e., the typical CR potential signal is also a function of other environmental stresses, e.g., vapor pressure deficit. In summary, our results yield valuable insight into the role of vertical atmospheric and vegetative conductances in CR.

Pollution in the urban soils of Lianyungang, China, evaluated using a pollution index, mobility of heavy metals, and enzymatic activities.

PubMed

Li, Yu; Li, Hong-Guan; Liu, Fu-Cheng

2017-01-01

Soil samples from 16 urban sites in Lianyungang, China were collected and analyzed. A pollution index was used to assess the potential ecological risk of heavy metals and a sequential extraction procedure was used to evaluate the relative distribution of Cu, Zn, Pb, Cd, Cr, and As in exchangeable, carbonate, Fe/Mn oxide, organic/sulfide, and residual fractions. The mobility of heavy metals and urease (URE) activity, alkaline phosphatase (ALP) activity, and invertase (INV) activity of soils was determined. The results showed that the average concentrations of Cu, Zn, Pb, Cd, Cr, and As in Lianyungang soils were much higher than those in the coastal city soil background values of Jiangsu and China. Among the five studied regions (utilities, commercial, industrial, tourism, and roadside), the industrial region had the highest metal concentrations demonstrating that land use had a significant impact on the accumulation of heavy metals in Lianyungang soils. Compared to the other metals, Cd showed the highest ecological risk. According to chemical partitioning, Cu was associated with the organic/sulfides and Pb and Zn were mainly in the carbonate and the Fe/Mn oxide phase. The greatest amounts of Cd were found in exchangeable and carbonate fractions, while Cr and As were mainly in the residual fraction. Cd had the highest mobility of all metals, and the order of mobility (highest to lowest) of heavy metals in Lianyungang soils was Cd > Zn > Pb > Cu > As > Cr. Soil urease activity, alkaline phosphatase activity, and invertase activity varied considerably in different pollution degree sites. Soil enzyme activities had the lowest levels in roadside and industrial regions. Across all the soil data in the five regions, the total Cu, Zn, Pb, Cd, Cr, and As level was negatively correlated with urease activity, alkaline phosphatase activity, and invertase activity, but the relationship was not significant. In the industrial region, alkaline phosphatase activity had significant negative correlations with total Cu, Pb, Cr, Zn, Cd, and heavy metal fractions. This showed that alkaline phosphatase activity was sensitive to heavy metals in heavily contaminated regions, whereas urease and invertase were less affected. The combination of the various methods may offer a powerful analytical technique in the study of heavy metal pollution in street soil.

[Study on corrosion resistance of three non-noble porcelain alloys].

PubMed

Wu, Zhikai; Xu, Sheng; Li, Wei; Teng, Jin; Li, Ning

2011-10-01

To study the electrochemical corrosion behavior of Co-Cr, Ni-Cr and Ni-Cr-Be based porcelain alloys in NaCl solution. Five samples of each alloy were made respectively, electric polarization curve of each alloy was obtained using potentiodynamic polarization technique. Self-corrosion potential (E(corr)), self-corrosion current density (I(corr), passive region and transpassivation potential were tested. Microstructure and constituent was examined using scanning electron microscopy and energy dispersive spectroscopy. Co-Cr alloy possessed the most desirable corrosion resistance because of its integrated, homogeneous and compact passive film. The poor compactness of Ni-Cr alloy's passive film decreased its corrosion resistance. Ni-Cr-Be alloy exhibited the worst corrosion resistance due to the Cr and Mo depleted Ni-Be eutectic phases in the alloy. Taking biological security into consideration, it is necessary to avoid the application of porcelain alloys with Be element. Co-Cr alloy with better biocompatibility possesses much broader prospect in the field of dental restoration.

Magnetic interaction reversal in watermelon nanostructured Cr-doped Fe nanoclusters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kaur, Maninder; Qiang, You, E-mail: youqiang@uidaho.edu; Dai, Qilin

2013-11-11

Cr-doped core-shell Fe/Fe-oxide nanoclusters (NCs) were synthesized at varied atomic percentages of Cr from 0 at. % to 8 at. %. The low concentrations of Cr (<10 at. %) were selected in order to inhibit the complete conversion of the Fe-oxide shell to Cr{sub 2}O{sub 3} and the Fe core to FeCr alloy. The magnetic interaction in Fe/Fe-oxide NCs (∼25 nm) can be controlled by antiferromagnetic Cr-dopant. We report the origin of σ-FeCr phase at very low Cr concentration (2 at. %) unlike in previous studies, and the interaction reversal from dipolar to exchange interaction in watermelon-like Cr-doped core-shell NCs.

Persistence of weight loss and acquired behaviors 2 y after stopping a 2-y calorie restriction intervention.

PubMed

Marlatt, Kara L; Redman, Leanne M; Burton, Jeff H; Martin, Corby K; Ravussin, Eric

2017-04-01

Background: Calorie restriction (CR) influences aging processes and extends average and maximal life spans. The CALERIE 2 (Comprehensive Assessment of Long-Term Effects of Reducing Intake of Energy Phase 2) study was the first randomized clinical trial to examine the metabolic and psychological effects of CR in nonobese humans. Objective: We conducted a 2-y follow-up study of adults who underwent 2 y of CR or ad libitum (control) consumption and determined whether weight loss and acquired behaviors persisted after the study ended when participants determined their own lifestyle behaviors. Design: In this prospective, longitudinal study, we assessed differences in weight, body composition, psychological function, and energy expenditure in 39 nonobese [body mass index (in kg/m 2 ): 22-28] men and women (25% CR: n = 24; control: n = 15) 12 and 24 mo after they completed the CALERIE 2 study at Pennington Biomedical. Results: Of 39 participants who were in the follow-up study, 29 subjects (CR: n = 18; control: n = 11) completed all visits at follow-up months 12 and 24. After the CR intervention, a mean ± SEM weight loss of 9.0 ± 0.6 kg was observed in the CR group, in which only 54% of the weight was regained 2 y later. Despite such a regain, weight, the percentage of body fat, and fat mass remained significantly reduced from baseline throughout follow-up and remained significantly less than in the control group ( P < 0.05). At follow-up, the CR group retained higher degrees of dietary restraint and avoidance of certain foods. Conclusion: After a 2-y intensive CR intervention, ∼50% of CR-induced weight loss was maintained 2 y later, which was probably the result of lasting effects on acquired behaviors and dietary restraint. This trial was registered at clinicaltrials.gov as NCT00943215. © 2017 American Society for Nutrition.

Virtual Reality for Upper Limb Rehabilitation in Subacute and Chronic Stroke: A Randomized Controlled Trial.

PubMed

Kiper, Pawel; Szczudlik, Andrzej; Agostini, Michela; Opara, Jozef; Nowobilski, Roman; Ventura, Laura; Tonin, Paolo; Turolla, Andrea

2018-05-01

To evaluate the effectiveness of reinforced feedback in virtual environment (RFVE) treatment combined with conventional rehabilitation (CR) in comparison with CR alone, and to study whether changes are related to stroke etiology (ie, ischemic, hemorrhagic). Randomized controlled trial. Hospital facility for intensive rehabilitation. Patients (N=136) within 1 year from onset of a single stroke (ischemic: n=78, hemorrhagic: n=58). The experimental treatment was based on the combination of RFVE with CR, whereas control treatment was based on the same amount of CR. Both treatments lasted 2 hours daily, 5d/wk, for 4 weeks. Fugl-Meyer upper extremity scale (F-M UE) (primary outcome), FIM, National Institutes of Health Stroke Scale (NIHSS), and Edmonton Symptom Assessment Scale (ESAS) (secondary outcomes). Kinematic parameters of requested movements included duration (time), mean linear velocity (speed), and number of submovements (peak) (secondary outcomes). Patients were randomized in 2 groups (RFVE with CR: n=68, CR: n=68) and stratified by stroke etiology (ischemic or hemorrhagic). Both groups improved after treatment, but the experimental group had better results than the control group (Mann-Whitney U test) for F-M UE (P<.001), FIM (P<.001), NIHSS (P≤.014), ESAS (P≤.022), time (P<.001), speed (P<.001), and peak (P<.001). Stroke etiology did not have significant effects on patient outcomes. The RFVE therapy combined with CR treatment promotes better outcomes for upper limb than the same amount of CR, regardless of stroke etiology. Copyright © 2018 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Proton magnetic resonance spectroscopic creatine correlates with creatine transporter protein density in rat brain.

PubMed

Sartorius, Alexander; Lugenbiel, Patrick; Mahlstedt, Magdalena M; Ende, Gabriele; Schloss, Patrick; Vollmayr, Barbara

2008-07-30

Creatine (Cr) is an amino acid, which upon phosphorylation is utilized as an energy reservoir in cells with high-energy demand. The ongoing catabolism of creatine to creatinine requires a permanent creatine replenishment into the cells. Because neurons themselves cannot synthesize creatine, they have to take it up via the creatine transporter (CrT). Thus, the concentration of intracellular Cr available for the Cr/PCr shuttle system depends on the expression level of CrT protein. The proton magnetic resonance spectroscopy (MRS) creatine peak (total creatine=tCr) constitutes of two metabolites, namely Cr and phosphocreatine (PCr). We have quantified the level of CrT protein expression with western blotting and compared it to tCr content as estimated by in vitro MRS in Sprague-Dawley rats. Under the assumption of hemispheric symmetry, we took identical samples from left and right hemisphere, which were used for in vitro MRS (tCr) and for western blotting (CrT), respectively. Altogether, it was possible to take 90 corresponding brain samples from 31 animals. A Pearson linear regression analysis for CrT and tCr revealed p<0.0001, explaining 14% of the variance. Since MR-detectable alterations of tCr in the human brain are widespread (e.g. in most major psychiatric disorders proton MRS detectable tCr alterations have been described as regionally and usually state dependent) it is stringent to elucidate their meaning. An influence of tCr on the brain's energy regulating system seems plausible.

Pattern of calbindin-D28k and calretinin immunoreactivity in the brain of Xenopus laevis during embryonic and larval development.

PubMed

Morona, Ruth; González, Agustín

2013-01-01

The present study represents a detailed spatiotemporal analysis of the localization of calbindin-D28k (CB) and calretinin (CR) immunoreactive structures in the brain of Xenopus laevis throughout development, conducted with the aim to correlate the onset of the immunoreactivity with the development of compartmentalization of distinct subdivisions recently identified in the brain of adult amphibians and primarily highlighted when analyzed within a segmental paradigm. CR and CB are expressed early in the brain and showed a progressively increasing expression throughout development, although transient expression in some neuronal subpopulations was also noted. Common and distinct characteristics in Xenopus, as compared with reported features during development in the brain of mammals, were observed. The development of specific regions in the forebrain such as the olfactory bulbs, the components of the basal ganglia and the amygdaloid complex, the alar and basal hypothalamic regions, and the distinct diencephalic neuromeres could be analyzed on the basis of the distinct expression of CB and CR in subregions. Similarly, the compartments of the mesencephalon and the main rhombencephalic regions, including the cerebellum, were differently highlighted by their specific content in CB and CR throughout development. Our results show the usefulness of the analysis of the distribution of these proteins as a tool in neuroanatomy to interpret developmental aspects of many brain regions. Copyright © 2012 Wiley Periodicals, Inc.

A comprehensive analysis of heavy metals in urban road dust of Xi'an, China: Contamination, source apportionment and spatial distribution.

PubMed

Pan, Huiyun; Lu, Xinwei; Lei, Kai

2017-12-31

A detailed investigation was conducted to study heavy metal contamination in road dust from four regions of Xi'an, Northwest China. The concentrations of eight heavy metals Co, Cr, Cu, Mn, Ni, Pb, Zn and V were determined by X-Ray Fluorescence. The mean concentrations of these elements were: 30.9mgkg -1 Co, 145.0mgkg -1 Cr, 54.7mgkg -1 Cu, 510.5mgkg -1 Mn, 30.8mgkg -1 Ni, 124.5mgkg -1 Pb, 69.6mgkg -1 V and 268.6mgkg -1 Zn. There was significant enrichment of Pb, Zn, Co, Cu and Cr based on geo-accumulation index value. Multivariate statistical analysis showed that levels of Cu, Pb, Zn, Co and Cr were controlled by anthropogenic activities, while levels of Mn, Ni and V were associated with natural sources. Principle component analysis and multiple linear regression were applied to determine the source apportionment. The results showed that traffic was the main source with a percent contribution of 53.4%. Natural sources contributed 26.5%, and other anthropogenic pollution sources contributed 20.1%. Clear heavy metal pollution hotspots were identified by GIS mapping. The location of point pollution sources and prevailing wind direction were found to be important factors in the spatial distribution of heavy metals. Copyright © 2017 Elsevier B.V. All rights reserved.

Cellular and molecular identity of tumor-associated macrophages in glioblastoma

PubMed Central

Chen, Zhihong; Feng, Xi; Herting, Cameron J.; Garcia, Virginia Alvarez; Nie, Kai; Pong, Winnie W.; Rasmussen, Rikke; Dwivedi, Bhakti; Seby, Sandra; Wolf, Susanne A.; Gutmann, David H.; Hambardzumyan, Dolores

2017-01-01

In glioblastoma (GBM), tumor-associated macrophages (TAM) represent up to one half of the cells of the tumor mass, including both infiltrating macrophages and resident brain microglia. In an effort to delineate the temporal and spatial dynamics of TAM composition during gliomagenesis, we employed two genetically engineered mouse models where oncogenic drivers and fluorescent reporters were expressed coordinately under the control of the monocyte/microglia-selective Cx3cr1 or Ccr2 promoters, respectively. Using this approach, we demonstrated that CX3CR1LoCCR2Hi monocytes were recruited to the glioblastoma, where they transitioned to CX3CR1HiCCR2Lo macrophages and CX3CR1HiCCR2− microglia-like cells. Infiltrating macrophages/monocytes constituted ~85% of the total TAM population, with resident microglia accounting for the ~15% remaining. Bone marrow-derived infiltrating macrophages/monocytes were recruited to the tumor early during GBM initiation, where they localized preferentially to perivascular areas. In contrast, resident microglia were localized mainly to peritumoral regions. RNA-sequencing analyses revealed differential gene expression patterns unique to infiltrating and resident cells, suggesting unique functions for each TAM population. Notably, limiting monocyte infiltration via Ccl2 genetic ablation prolonged the survival of tumor-bearing mice. Our findings illuminate the unique composition and functions of infiltrating and resident myeloid cells in GBM, establishing a rationale to target infiltrating cells in this neoplasm. PMID:28235764

Characterization of Somatic Mutations in Air Pollution-Related Lung Cancer.

PubMed

Yu, Xian-Jun; Yang, Min-Jun; Zhou, Bo; Wang, Gui-Zhen; Huang, Yun-Chao; Wu, Li-Chuan; Cheng, Xin; Wen, Zhe-Sheng; Huang, Jin-Yan; Zhang, Yun-Dong; Gao, Xiao-Hong; Li, Gao-Feng; He, Shui-Wang; Gu, Zhao-Hui; Ma, Liang; Pan, Chun-Ming; Wang, Ping; Chen, Hao-Bin; Hong, Zhi-Peng; Wang, Xiao-Lu; Mao, Wen-Jing; Jin, Xiao-Long; Kang, Hui; Chen, Shu-Ting; Zhu, Yong-Qiang; Gu, Wen-Yi; Liu, Zi; Dong, Hui; Tian, Lin-Wei; Chen, Sai-Juan; Cao, Yi; Wang, Sheng-Yue; Zhou, Guang-Biao

2015-06-01

Air pollution has been classified as Group 1 carcinogenic to humans, but the underlying tumorigenesis remains unclear. In Xuanwei City of Yunnan Province, the lung cancer incidence is among the highest in China attributed to severe air pollution generated by combustion of smoky coal, providing a unique opportunity to dissect lung carcinogenesis of air pollution. Here we analyzed the somatic mutations of 164 non-small cell lung cancers (NSCLCs) from Xuanwei and control regions (CR) where smoky coal was not used. Whole genome sequencing revealed a mean of 289 somatic exonic mutations per tumor and the frequent C:G → A:T nucleotide substitutions in Xuanwei NSCLCs. Exome sequencing of 2010 genes showed that Xuanwei and CR NSCLCs had a mean of 68 and 22 mutated genes per tumor, respectively (p < 0.0001). We found 167 genes (including TP53, RYR2, KRAS, CACNA1E) which had significantly higher mutation frequencies in Xuanwei than CR patients, and mutations in most genes in Xuanwei NSCLCs differed from those in CR cases. The mutation rates of 70 genes (e.g., RYR2, MYH3, GPR144, CACNA1E) were associated with patients' lifetime benzo(a)pyrene exposure. This study uncovers the mutation spectrum of air pollution-related lung cancers, and provides evidence for pollution exposure-genomic mutation relationship at a large scale.

Chromium Stable Isotope Fractionation - An Indicator of Hexavalent Chromium Reduction.

NASA Astrophysics Data System (ADS)

Ellis, A.; Johnson, T. M.; Bullen, T. D.

2001-12-01

Chromium is a common anthropogenic contaminant in surface water and ground water, and is also of interest in oceanography. It is redox-active; the two common valences in natural waters are Cr(VI), which is highly soluble and toxic, and Cr(III), which is relatively insoluble. Redox reactions thus control Cr mobility in aqueous solutions, and reduction of Cr(VI) to Cr(III) is the most important reaction controlling attenuation of Cr in groundwater. Our results show that Cr(VI) reduction favors the lighter isotopes and leads to enrichment of heavier isotopes in the remaining Cr(VI). Cr isotope measurements thus show great promise as indicators of Cr(VI) reduction. We report here the first measurements of the magnitude of Cr isotope fractionation during Cr(VI) reduction and variations in δ 53Cr values obtained from three contaminated sites. Experiments were conducted to measure Cr isotope fractionation during Cr(VI) reduction by suspensions of magnetite and unamended sediments from a local pond, Urbana, IL and San Francisco Estuary near Martinez, CA. Suspensions were incubated anaerobically with constant shaking, and complete Cr(VI) reduction occurred within a few days. Cr(VI) from intermediate time points in the experiments was purified via ion exchange and 53Cr/52Cr ratios were measured via TIMS with a double isotope spike. The instantaneous per mil fractionation, ɛ , was calculated assuming a Rayleigh fractionation model. The ɛ for Cr(VI) reduction on magnetite surfaces yielded a fractionation of -3.5 ‰ . The ɛ values for the pond and estuary sediments were -3.5 ‰ and -3.3 ‰ respectively. The size of this Cr isotope fractionation is encouraging, as current precision is 0.2 \\permil. δ 53Cr values in dissolved Cr(VI) from three contaminated sites range from 1.1 ‰ to 5.8 ‰ , suggesting that Cr(VI) reduction has occurred and has induced isotopic fractionation in these settings. δ 53Cr values measured from Cr(VI) in plating baths show little or no fractionation during plating operations during up to 5 years of use. These results demonstrate that Cr stable isotope analyses should be a highly practical indicator of the critical chromate reduction reaction, and an otherwise useful geologic and oceanographic tool.

The Distribution and Health Risk Assessment of Metals in Soils in the Vicinity of Industrial Sites in Dongguan, China

PubMed Central

Liu, Chao; Lu, Liwen; Huang, Ting; Huang, Yalin; Ding, Lei; Zhao, Weituo

2016-01-01

Exponential industrialization and rapid urbanization have resulted in contamination of soil by metals from anthropogenic sources in Dongguan, China. The aims of this research were to determine the concentration and distribution of various metals (arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), lead (Pb) and zinc (Zn)) in soils and identify their potential health risks for local residents. A total of 106 soil samples were collected from the vicinity of industrial sites in Dongguan. Two types of samples were collected from each site: topsoil (0–20 cm, TS) and shallow soil (20–50 cm, SS). Results showed that the soils were contaminated by metals and pollution was mainly focused on TS. The geoaccumulation index (Igeo) and pollution indexes (PI) implied that there was a slight increase in the concentrations of Cd, Cu, Hg, Ni, and Pb, but the metal pollution caused by industrial activities was less severe, and elements of As and Cr exhibited non-pollution level. The risk assessment results suggested that there was a potential health risk associated with As and Cr exposure for residents because the carcinogenic risks of As and Cr via corresponding exposure pathways exceeded the safety limit of 10−6 (the acceptable level of carcinogenic risk for humans). Furthermore, oral ingestion and inhalation of soil particles are the main exposure pathways for As and Cr to enter the human body. This study may provide basic information of metal pollution control and human health protection in the vicinity of industrial regions. PMID:27548198

Improved leukemia-free survival after postconsolidation immunotherapy with histamine dihydrochloride and interleukin-2 in acute myeloid leukemia: results of a randomized phase 3 trial.

PubMed

Brune, Mats; Castaigne, Sylvie; Catalano, John; Gehlsen, Kurt; Ho, Anthony D; Hofmann, Wolf-Karsten; Hogge, Donna E; Nilsson, Bo; Or, Reuven; Romero, Ana I; Rowe, Jacob M; Simonsson, Bengt; Spearing, Ruth; Stadtmauer, Edward A; Szer, Jeff; Wallhult, Elisabeth; Hellstrand, Kristoffer

2006-07-01

The primary objective of this phase 3 study was to determine whether postconsolidation immunotherapy with interleukin-2 (IL-2) and histamine dihydrochloride (HDC) improved the leukemia-free survival (LFS) of adult patients with acute myeloid leukemia (AML) in complete remission (CR). Three hundred twenty patients with AML (median age, 57 years; range, 18-84 years) were stratified by CR1 or subsequent CR (CR > 1) and randomly assigned to treatment with HDC/IL-2 or no treatment (control). Treatment comprised 10 21-day cycles with IL-2 (16 400 U/kg) plus HDC (0.5 mg); both compounds were administered by subcutaneous injection twice daily. Study arms were balanced for age, sex, previous treatment, leukemic karyotypes, time from CR to inclusion, and frequency of secondary leukemia. Three years after enrollment of the last patient, treatment with HDC/IL-2 was found to improve LFS over control in the study population (CR1 + CR > 1, n = 320; P < .01, log-rank test). For patients in CR1 (n = 261), treatment significantly improved LFS (P = .01) with 3-year LFS estimates of 40% (HDC/IL-2) compared with 26% (control). Side effects were typically mild to moderate. These results indicate that HDC/IL-2 treatment offers an efficacious and tolerable treatment for patients with AML in remission.

Galactic CR in the Heliosphere according to NM data, 3. Results for even solar cycles 20 and 22.

NASA Astrophysics Data System (ADS)

Dorman, L.; Dorman, I.; Iucci, N.; Parisi, M.; Villoresi, G.; Zukerman, I.

We found that the maximum of correlation coefficient between cosmic ray (CR) intensity and solar activity (SA) variations is occurred for even cycles 20 and 22 for about two-three times in the shorter time than for odd cycles 19 and 21. We came to conclusion that this difference is caused by CR drift effects: during even cycle drifts produced the small increasing of CR global modulation (additional to the caused by convection-diffusion mechanism) in the period from minimum to maximum of SA, and after the maximum of SA up to the minimum- about the same decreasing of CR modulation. This gives sufficient decreasing of observed time lag between CR and- SA in even solar cycles. We analyzed monthly and 11 months smoothed data of (CR) intensity observed by neutron monitors with different cut-off rigidities for even solar cycles 20 and 22. We use a special model described the connection between solar activity (characterized by monthly sunspot numbers) and CR convection- diff usion global modulation with taking into account time-lag of processes in the Heliosphere relative to the active processes on the Sun. For taking into account drifts we use models described in literature. In the first we correct observed long-term CR modulation on drifts with different amplitudes from 0 (no drifts), then 0.15%, 0.25%,... up to 4%. For each expected amplitude of drifts we determine the correlation coefficient between expected CR variations and observed by neutron monitors with different cut - off rigidities for different times of solar wind transportation from the Sun to the boundary of the modulation region from 1 to 60 average months (it corresponds approximately to dimension of modulation region from about 6 to 360 AU). We compare observed res ults for even solar cycles 20 and 22.

Investigation of the nanostructure and wear properties of physical vapor deposited CrCuN nanocomposite coatings

NASA Astrophysics Data System (ADS)

Baker, M. A.; Kench, P. J.; Tsotsos, C.; Gibson, P. N.; Leyland, A.; Matthews, A.

2005-05-01

This article presents results on CrCuN nanocomposite coatings grown by physical vapor deposition. The immiscibility of Cr (containing a supersaturation of nitrogen) and Cu offers the potential of depositing a predominantly metallic (and therefore tough) nanocomposite, composed of small Cr(N) metallic and/or β-Cr2N ceramic grains interdispersed in a (minority) Cu matrix. A range of CrCuN compositions have been deposited using a hot-filament enhanced unbalanced magnetron sputtering system. The stoichiometry and nanostructure have been studied by x-ray photoelectron spectroscopy, transmission electron microscopy, scanning electron microscopy, and x-ray diffraction. Hardness, wear resistance, and impact resistance have been determined by nanoindentation, reciprocating-sliding, and ball-on-plate high-cycle impact. Evolution of the nanostructure as a function of composition and correlations of the nanostructure and mechanical properties of the CrCuN coatings are discussed. A nanostructure comprised of 1-3 nm α-Cr(N) and β-Cr2N grains separated by intergranular regions of Cu gives rise to a coating with significantly enhanced resistance to impact wear.

Brain metabolic correlates of decision making in amnestic mild cognitive impairment.

PubMed

Griffith, H Randall; Okonkwo, Ozioma C; den Hollander, Jan A; Belue, Katherine; Copeland, Jacqueline; Harrell, Lindy E; Brockington, John C; Clark, David G; Marson, Daniel C

2010-01-01

Persons with amnestic mild cognitive impairment (MCI) have subtle impairments in medical decision-making capacity (MDC). We examined the relationship between proton magnetic resonance spectroscopy (MRS) and MDC in MCI. Twenty-nine MCI patients and 42 controls underwent MRS to obtain ratios of N-acetylaspartate (NAA)/Creatine (Cr), Choline (Cho)/Cr, and myo-Inositol (mI)/Cr of the posterior cingulate. They also completed the Capacity to Consent to Treatment Instrument (CCTI), a vignette-based instrument measuring decisional standards of expressing choice, appreciating consequences of choice, providing rational reasons for choice, and understanding treatment choices. Patients showed abnormal MRS ratios of mI/Cr and Cho/Cr compared to controls, and impairments on the CCTI understanding and reasoning Standards. Performance on the reasoning standard of the CCTI was correlated with NAA/Cr (r = .46, p < .05). The relationship of NAA/Cr with decision-making suggests a role for posterior cortical neuronal functioning in performance of complex IADLs in MCI.

Treatment of Alkaline Cr(VI)-Contaminated Leachate with an Alkaliphilic Metal-Reducing Bacterium.

PubMed

Watts, Mathew P; Khijniak, Tatiana V; Boothman, Christopher; Lloyd, Jonathan R

2015-08-15

Chromium in its toxic Cr(VI) valence state is a common contaminant particularly associated with alkaline environments. A well-publicized case of this occurred in Glasgow, United Kingdom, where poorly controlled disposal of a cementitious industrial by-product, chromite ore processing residue (COPR), has resulted in extensive contamination by Cr(VI)-contaminated alkaline leachates. In the search for viable bioremediation treatments for Cr(VI), a variety of bacteria that are capable of reduction of the toxic and highly soluble Cr(VI) to the relatively nontoxic and less mobile Cr(III) oxidation state, predominantly under circumneutral pH conditions, have been isolated. Recently, however, alkaliphilic bacteria that have the potential to reduce Cr(VI) under alkaline conditions have been identified. This study focuses on the application of a metal-reducing bacterium to the remediation of alkaline Cr(VI)-contaminated leachates from COPR. This bacterium, belonging to the Halomonas genus, was found to exhibit growth concomitant to Cr(VI) reduction under alkaline conditions (pH 10). Bacterial cells were able to rapidly remove high concentrations of aqueous Cr(VI) (2.5 mM) under anaerobic conditions, up to a starting pH of 11. Cr(VI) reduction rates were controlled by pH, with slower removal observed at pH 11, compared to pH 10, while no removal was observed at pH 12. The reduction of aqueous Cr(VI) resulted in the precipitation of Cr(III) biominerals, which were characterized using transmission electron microscopy and energy-dispersive X-ray analysis (TEM-EDX) and X-ray photoelectron spectroscopy (XPS). The effectiveness of this haloalkaliphilic bacterium for Cr(VI) reduction at high pH suggests potential for its use as an in situ treatment of COPR and other alkaline Cr(VI)-contaminated environments. Copyright © 2015, Watts et al.

A Meta-analytic Review of Non-specific Effects in Randomized Controlled Trials of Cognitive Remediation for Schizophrenia.

PubMed

Radhakrishnan, Rajiv; Kiluk, Brian D; Tsai, Jack

2016-03-01

Cognitive remediation (CR) has been found to improve cognitive performance among adults with schizophrenia in randomized controlled trials (RCTs). However, improvements in cognitive performance are often observed in the control groups of RCTs as well. There has been no comprehensive examination of change in control groups for CR, which may inform trial methodology and improve our understanding of measured outcomes for cognitive remediation. In this meta-analysis, we calculated pre-post change in cognitive test performance within control groups of RCTs in 32 CR trials (n = 794 participants) published between 1970 and 2011, and examined the association between pre-post change and sample size, duration of treatment, type of control group, and participants' age, intelligence, duration of illness, and psychiatric symptoms. Results showed that control groups in CR trials showed small effect size changes (Cohen's d = 0.12 ± 0.16) in cognitive test performance over the trial duration. Study characteristics associated with pre-post change included participant age and sample size. These findings suggest attention to change in control groups may help improve detection of cognitive remediation effects for schizophrenia.

Parkinson's disease: in vivo metabolic changes in the frontal and parietal cortices in 6-OHDA treated rats during different periods.

PubMed

Hou, Zhongyu; Zhang, Zhonghe; Meng, Haiwei; Lin, Xiangtao; Sun, Bo; Lei, Hao; Fang, Ke; Fang, Fang; Liu, Maili; Liu, Shuwei

2014-02-01

This study aims to investigate metabolic changes in frontal and parietal cortices in the 6-OHDA induced Parkinson's rats. Ratios of N-acetyl-aspartic acid/creatine (NAA/Cr), choline/creatine (Cho/Cr), and glumatic acid and glutamine glutaminic acid/creatine (Glx/Cr) of regions of interests (ROIs) in the frontal and parietal cortices, and the substantia nigra were analyzed. NAA/Cr, Cho/Cr and Glx/Cr in the frontal and parietal cortices in the lesion side did not show any significant differences two weeks after operation compared with the contralateral side (p > 0.05). NAA/Cr in the frontal cortex in the lesion side was significantly lower in the five weeks after operation; Cho/Cr remained normal; Glx/Cr increased (p < 0.05), and all ratios of parietal cortex were normal. In the eight weeks after operation, NAA/Cr in the frontal cortex in the lesion side was lower than that of the five weeks (p < 0.01), Cho/Cr still remained normal while Glx/Cr was higher than before (p < 0.01). Regarding the parietal cortex, NAA/Cr increased significantly, while Cho/Cr and Glx/Cr remained normal. In the 12 weeks after operation, NAA/Cr, Cho/Cr and Glx/Cr in frontal cortex were consistent with that of the eight weeks, while they remained at the normal level in parietal cortex. The NAA/Cr in the substantia nigra decreased and Cho/Cr increased significantly during 2-8 weeks, and remained at the same level during 8-12 weeks. There are metabolic disturbances in PD rats. The transient hyperfunction in the parietal cortex can be considered as a compensation for the dysfunction of the frontal cortex and substantia nigra.

Trace elements and radon in groundwater across the United States, 1992-2003

USGS Publications Warehouse

Ayotte, Joseph D.; Gronberg, Jo Ann M.; Apodaca, Lori E.

2011-01-01

Trace-element concentrations in groundwater were evaluated for samples collected between 1992 and 2003 from aquifers across the United States as part of the U.S. Geological Survey National Water-Quality Assessment Program. This study describes the first comprehensive analysis of those data by assessing occurrence (concentrations above analytical reporting levels) and by comparing concentrations to human-health benchmarks (HHBs). Data from 5,183 monitoring and drinking-water wells representing more than 40 principal and other aquifers in humid and dry regions and in various land-use settings were used in the analysis. Trace elements measured include aluminum (Al), antimony (Sb), arsenic (As), barium (Ba), beryllium (Be), boron (B), cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), iron (Fe), lead (Pb), lithium (Li), manganese (Mn), molybdenum (Mo), nickel (Ni), selenium (Se), silver (Ag), strontium (Sr), thallium (Tl), uranium (U), vanadium (V), and zinc (Zn). Radon (Rn) gas also was measured and is included in the data analysis. Climate influenced the occurrence and distribution of trace elements in groundwater whereby more trace elements occurred and were found at greater concentrations in wells in drier regions of the United States than in humid regions. In particular, the concentrations of As, Ba, B, Cr, Cu, Mo, Ni, Se, Sr, U, V, and Zn were greater in the drier regions, where processes such as chemical evolution, ion complexation, evaporative concentration, and redox (oxidation-reduction) controls act to varying degrees to mobilize these elements. Al, Co, Fe, Pb, and Mn concentrations in groundwater were greater in humid regions of the United States than in dry regions, partly in response to lower groundwater pH and (or) more frequent anoxic conditions. In groundwater from humid regions, concentrations of Cu, Pb, Rn, and Zn were significantly greater in drinking-water wells than in monitoring wells. Samples from drinking-water wells in dry regions had greater concentrations of As, Ba, Pb, Li, Sr, V, and Zn, than samples from monitoring wells. In humid regions, however, concentrations of most trace elements were greater in monitoring wells than in drinking-water wells; the exceptions were Cu, Pb, Zn, and Rn. Cu, Pb, and Zn are common trace elements in pumps and pipes used in the construction of drinking-water wells, and contamination from these sources may have contributed to their concentrations. Al, Sb, Ba, B, Cr, Co, Fe, Mn, Mo, Ni, Se, Sr, and U concentrations were all greater in monitoring wells than in drinking-water wells in humid regions. Groundwater from wells in agricultural settings had greater concentrations of As, Mo, and U than groundwater from wells in urban settings, possibly owing to greater pH in the agricultural wells. Significantly greater concentrations of B, Cr, Se, Ag, Sr, and V also were found in agricultural wells in dry regions. Groundwater from dry-region urban wells had greater concentrations of Co, Fe, Pb, Li, Mn, and specific conductance than groundwater from agricultural wells. The geologic composition of aquifers and aquifer geochemistry are among the major factors affecting trace-element occurrence. Trace-element concentrations in groundwater were characterized in aquifers from eight major groups based on geologic material, including (1) unconsolidated sand and gravel; (2) glacial unconsolidated sand and gravel; (3) semiconsolidated sand; (4) sandstone; (5) sandstone and carbonate rock; (6) carbonate rock; (7) basaltic and other volcanic rock; and (8) crystalline rock. The majority of groundwater samples and the largest percentages of exceedences of HHBs were in the glacial and nonglacial unconsolidated sand and gravel aquifers; in these aquifers, As, Mn, and U are the most common trace elements exceeding HHBs. Overall, 19 percent of wells (962 of 5,097) exceeded an HHB for at least one trace element. The trace elements with HHBs included in this summary were Sb, As, Ba, Be, B, Cd, Cr,

The effects of dietary supplementation with chromium picolinate throughout gestation on productive performance, Cr concentration, serum parameters, and colostrum composition in sows.

PubMed

Wang, Liansheng; Shi, Zhan; Jia, Zhiqiang; Su, Binchao; Shi, Baoming; Shan, Anshan

2013-07-01

The objective of this study was to determine the effects of supplemental chromium as chromium picolinate (CrPic) on productive performance, chromium (Cr) concentration, serum parameters, and colostrum composition in sows. Thirty Yorkshire sows were bred with semen from a pool of Landrace boars. The sows were equally grouped and treated with either a diet containing 0 (control) or 400 ppb dietary Cr supplementation throughout gestation. The sows received the same basal diet based on corn-DDGS meal. Supplemental CrPic increased (P < 0.05) the sow body mass gain from the insemination to the day 110 of gestation in sows. No differences (P > 0.50) were observed in the gestation interval, sow mass, and backfat at insemination, after farrowing, at weaning and lactation loss. The number of piglets born alive, piglets per litter at weaning, and litter weaned mass were increased (P < 0.05) for those supplemented with CrPic compared with the control. However, the total number of piglets born, total born litter mass, average piglet birth body mass, born alive litter mass, and average born alive piglet mass did not differ among the treatments (P > 0.05). The placental masses of sows were similar among treatments (P > 0.05). Dietary supplementation with CrPic throughout gestation in sows showed increased (P < 0.01) concentration of Cr in the colostrum or serum at days 70 and 110. Compared with the control group, dietary supplementation with CrPic throughout gestation in sows decreased (P < 0.05) the serum insulin concentration, the glucose or serum urea nitrogen concentration at days 70 and 110. However, no differences (P > 0.05) were observed in total protein concentration among treatments. No differences (P > 0.05) were observed in total solids, protein, fat or lactose among sows fed the diets supplemented with CrPic compared with the control. This exciting finding provides evidence for an increase in mass gain and live-born piglets in sows supplemented with CrPic throughout gestation.

Development of Process Analytical Technology (PAT) methods for controlled release pellet coating.

PubMed

Avalle, P; Pollitt, M J; Bradley, K; Cooper, B; Pearce, G; Djemai, A; Fitzpatrick, S

2014-07-01

This work focused on the control of the manufacturing process for a controlled release (CR) pellet product, within a Quality by Design (QbD) framework. The manufacturing process was Wurster coating: firstly layering active pharmaceutical ingredient (API) onto sugar pellet cores and secondly a controlled release (CR) coating. For each of these two steps, development of a Process Analytical Technology (PAT) method is discussed and also a novel application of automated microscopy as the reference method. Ultimately, PAT methods should link to product performance and the two key Critical Quality Attributes (CQAs) for this CR product are assay and release rate, linked to the API and CR coating steps respectively. In this work, the link between near infra-red (NIR) spectra and those attributes was explored by chemometrics over the course of the coating process in a pilot scale industrial environment. Correlations were built between the NIR spectra and coating weight (for API amount), CR coating thickness and dissolution performance. These correlations allow the coating process to be monitored at-line and so better control of the product performance in line with QbD requirements. Copyright © 2014 Elsevier B.V. All rights reserved.

Conformational Dissection of a Viral Intrinsically Disordered Domain Involved in Cellular Transformation

PubMed Central

Perrone, Sebastián; Salvay, Andres G.; Chemes, Lucía B.; de Prat-Gay, Gonzalo

2013-01-01

Intrinsic disorder is abundant in viral genomes and provides conformational plasticity to its protein products. In order to gain insight into its structure-function relationships, we carried out a comprehensive analysis of structural propensities within the intrinsically disordered N-terminal domain from the human papillomavirus type-16 E7 oncoprotein (E7N). Two E7N segments located within the conserved CR1 and CR2 regions present transient α-helix structure. The helix in the CR1 region spans residues L8 to L13 and overlaps with the E2F mimic linear motif. The second helix, located within the highly acidic CR2 region, presents a pH-dependent structural transition. At neutral pH the helix spans residues P17 to N29, which include the retinoblastoma tumor suppressor LxCxE binding motif (residues 21–29), while the acidic CKII-PEST region spanning residues E33 to I38 populates polyproline type II (PII) structure. At pH 5.0, the CR2 helix propagates up to residue I38 at the expense of loss of PII due to charge neutralization of acidic residues. Using truncated forms of HPV-16 E7, we confirmed that pH-induced changes in α-helix content are governed by the intrinsically disordered E7N domain. Interestingly, while at both pH the region encompassing the LxCxE motif adopts α-helical structure, the isolated 21–29 fragment including this stretch is unable to populate an α-helix even at high TFE concentrations. Thus, the E7N domain can populate dynamic but discrete structural ensembles by sampling α-helix-coil-PII-ß-sheet structures. This high plasticity may modulate the exposure of linear binding motifs responsible for its multi-target binding properties, leading to interference with key cell signaling pathways and eventually to cellular transformation by the virus. PMID:24086265

The Tropomyosin Binding Region of Cardiac Troponin T Modulates Crossbridge Recruitment Dynamics in Rat Cardiac Muscle Fibers

PubMed Central

Gollapudi, Sampath K.; Gallon, Clare E.; Chandra, Murali

2013-01-01

The cardiac muscle comprises dynamically interacting components that use allosteric/cooperative mechanisms to yield unique heart-specific properties. An essential protein in this allosteric/cooperative mechanism is cardiac muscle troponin T (cTnT), the central region (CR) and the T2 region of which differ significantly from those of fast skeletal muscle troponin T (fsTnT). To understand the biological significance of such sequence heterogeneity, we replaced the T1 or T2 domain of rat cTnT (RcT1 or RcT2) with its counterpart from rat fsTnT (RfsT1or RfsT2) to generate RfsT1-RcT2 and RcT1-RfsT2 recombinant proteins. In addition to contractile function measurements, dynamic features of RfsT1-RcT2 and RcT1-RfsT2 reconstituted rat cardiac muscle fibers were captured by fitting the recruitment-distortion model to force response of small amplitude (0.5%) muscle length changes. RfsT1-RcT2 fibers showed a ~40% decrease in tension and ~44% decrease in ATPase activity, but RcT1-RfsT2 fibers were unaffected. The magnitude of length-mediated increase in crossbridge recruitment (E0) decreased by ~33% and the speed of crossbridge recruitment (b) increased by ~100% in RfsT1-RcT2 fibers. Our data suggest the following: (1) the CR of cTnT modulates crossbridge recruitment dynamics; (2) the N-terminal end region of cTnT has a synergistic effect on the ability of CR to modulate crossbridge recruitment dynamics; (3) the T2 region is important for tuning the Ca2+ regulation of cardiac thin filaments. The combined effects of CR-Tm interactions and the modulating effect of the N-terminal end of cTnT on CR-Tm interactions may lead to the emergence of a unique property that tunes contractile dynamics to heart rates. PMID:23357173

Caloric restriction in young rats disturbs hippocampal neurogenesis and spatial learning.

PubMed

Cardoso, Armando; Marrana, Francisco; Andrade, José P

2016-09-01

It is widely known that caloric restriction (CR) has benefits on several organic systems, including the central nervous system. However, the majority of the CR studies was performed in adult animals and the information about the consequences on young populations is limited. In this study, we analyzed the effects of young-onset CR, started at 4weeks of age, in the number of neuropeptide Y (NPY)-containing neurons and in neurogenesis of the hippocampal formation, using doublecortin (DCX) and Ki67 as markers. Knowing that CR treatment could interfere with exploratory activity, anxiety, learning and memory we have analyzed the performance of the rats in the open-field, elevated plus-maze and Morris water maze tests. Animals aged 4weeks were randomly assigned to control or CR groups. Controls were maintained in the ad libitum regimen during 2months. The adolescent CR rats were fed, during 2months, with 60% of the amount of food consumed by controls. We have found that young-onset CR treatment did not affect the total number of NPY-immunopositive neurons in dentate hilus, CA3 and CA1 hippocampal subfields and did not change the exploratory activity and anxiety levels. Interestingly, we have found that young-onset CR might affect spatial learning process since those animals showed worse performance during the acquisition phase of Morris water maze. Furthermore, young-onset CR induced alterations of neurogenesis in the dentate subgranular layer that seems to underlie the impairment of spatial learning. Our data suggest that adolescent animals are vulnerable to CR treatment and that this diet is not suitable to be applied in this age phase. Copyright © 2016 Elsevier Inc. All rights reserved.

Improving coronary heart disease self-management using mobile technologies (Text4Heart): a randomised controlled trial protocol.

PubMed

Dale, Leila Pfaeffli; Whittaker, Robyn; Jiang, Yannan; Stewart, Ralph; Rolleston, Anna; Maddison, Ralph

2014-03-04

Cardiac rehabilitation (CR) is a secondary prevention program that offers education and support to assist patients with coronary heart disease (CHD) make lifestyle changes. Despite the benefits of CR, attendance at centre-based sessions remains low. Mobile technology (mHealth) has potential to reach more patients by delivering CR directly to mobile phones, thus providing an alternative to centre-based CR. The aim of this trial is to evaluate if a mHealth comprehensive CR program can improve adherence to healthy lifestyle behaviours (for example, physically active, fruit and vegetable intake, not smoking, low alcohol consumption) over and above usual CR services in New Zealand adults diagnosed with CHD. A two-arm, parallel, randomised controlled trial will be conducted at two Auckland hospitals in New Zealand. One hundred twenty participants will be randomised to receive a 24-week evidence- and theory-based personalised text message program and access to a supporting website in addition to usual CR care or usual CR care alone (control). The primary outcome is the proportion of participants adhering to healthy behaviours at 6 months, measured using a composite health behaviour score. Secondary outcomes include overall cardiovascular disease risk, body composition, illness perceptions, self-efficacy, hospital anxiety/depression and medication adherence. This study is one of the first to examine an mHealth-delivered comprehensive CR program. Strengths of the trial include quality research design and in-depth description of the intervention to aid replication. If effective, the trial has potential to augment standard CR practices and to be used as a model for other disease prevention or self-management programs. Australian New Zealand Clinical Trials Registry: ACTRN12613000901707.

Safety and efficacy of a novel Prunus domestica extract (Sitoprin, CR002) on testosterone-induced benign prostatic hyperplasia (BPH) in male Wistar rats.

PubMed

Swaroop, Anand; Bagchi, Manashi; Kumar, Pawan; Preuss, Harry G; Bagchi, Debasis

2015-01-01

The efficacy of a novel Prunus domestica bark extract (Sitoprin, CR002) was investigated on testosterone propionate (TP)-induced benign prostatic hyperplasia (BPH) in male Wistar rats. BPH was induced by daily subcutaneous administration of TP (3.0 mg/kg) over a period of 15 days (interim sacrifice group) and for an additional 21 days (terminal sacrifice group). We evaluated the dose-dependent efficacy (0, 50, 100 and 200 mg/kg body weight/day) of CR002 and a control group against BPH, and compared with a reference standard Prunus africana extract (CR001). Extensive clinical examinations were carried out on days 1, 7, 14, 21, 28 and 35 of treatment period to determine the onset, duration and severity of clinical signs. Clinical pathology, hematology, biochemistry and histopathology were performed on days 15 and 35, prior to necropsy. Animals were fasted overnight prior to blood collection. Prostate glands and tissues were examined. On day 36, histopathology of ventral prostrate of control rats demonstrates single layer of columnar mucin secreting epithelial cells along with a lumen occupied with eosinophilic secretion. In contrast, CR002 and CR001 groups (100 and 200 mg/kg/day) exhibited no hyperplasia and proliferation of epithelial cells. Prostate histopathology of these treated groups was comparable with control rats. The hyperplasia and hypertrophy of prostrate was reduced to single-layered cell indicating the efficacy of CR002 and CR001. Overall, results demonstrate that CR002 exhibits therapeutic efficacy/activity in TP-induced BPH in rats, which is comparable to CR001.

Effect of cardiac rehabilitation referral strategies on utilization rates: a prospective, controlled study.

PubMed

Grace, Sherry L; Russell, Kelly L; Reid, Robert D; Oh, Paul; Anand, Sonia; Rush, James; Williamson, Karen; Gupta, Milan; Alter, David A; Stewart, Donna E

2011-02-14

Although cardiac rehabilitation (CR) has been shown to reduce mortality and is a recommended component in clinical practice guidelines, CR referral and utilization rates remain low. Referral strategies have been implemented to increase CR use but have yet to be compared concurrently. To determine the optimal strategy to maximize CR referral, enrollment, and participation, we evaluated 3 referral strategies compared with usual care: "automatic" only via discharge order or electronic record, health care provider liaison only, or a combined approach. In this prospective controlled study, 2635 inpatients with coronary artery disease from 11 Ontario, Canada, hospitals using 1 of the 4 referral strategies completed a sociodemographic survey, and clinical data were extracted from medical charts. One year later, 1809 participants completed a mailed survey that assessed CR utilization. Referral strategies were compared using generalized estimating equations to control for effect of hospital. Adjusted analyses revealed referral strategy was significantly related to CR referral and enrollment (P<.001). Combined automatic and liaison referral resulted in the greatest CR use (odds ratio [OR], 8.41; 85.8% referral, 73.5% enrollment), followed by automatic only (OR, 3.27; 70.2% referral, 60.0% enrollment), and liaison only (OR, 3.35; 59.0% referral, 50.6% enrollment), compared with usual referral (32.2% referral, 29.0% enrollment). The degree of CR participation did not differ by referral strategy among referred participants (mean [SD] percentage of classes attended, 82.87% [27.20%]; P=.88). Automatic referral combined with a patient discussion can achieve among the highest rates of CR referral reported. Wider adoption of such strategies could ensure that 45% more patients being treated for cardiac disease would have access to and realize the benefits of CR. ©2011 American Medical Association. All rights reserved.

Pronounced reduction of acquisition of conditioned eyeblink responses in young adults with focal cerebellar lesions impedes conclusions on the role of the cerebellum in extinction and savings.

PubMed

Ernst, T M; Beyer, L; Mueller, O M; Göricke, S; Ladd, M E; Gerwig, M; Timmann, D

2016-05-01

Human cerebellar lesion studies provide good evidence that the cerebellum contributes to the acquisition of classically conditioned eyeblink responses (CRs). As yet, only one study used more advanced methods of lesion-symptom (or lesion-behavior) mapping to investigate which cerebellar areas are involved in CR acquisition in humans. Likewise, comparatively few studies investigated the contribution of the human cerebellum to CR extinction and savings. In this present study, young adults with focal cerebellar disease were tested. A subset of participants was expected to acquire enough conditioned responses to allow the investigation of extinction and saving effects. 19 participants with chronic surgical lesions of the cerebellum and 19 matched control subjects were tested. In all cerebellar subjects benign tumors of the cerebellum had been surgically removed. Eyeblink conditioning was performed using a standard short delay protocol. An initial unpaired control phase was followed by an acquisition phase, an extinction phase and a subsequent reacquisition phase. Structural 3T magnetic resonance images of the brain were acquired on the day of testing. Cerebellar lesions were normalized using methods optimized for the cerebellum. Subtraction analysis and Liebermeister tests were used to perform lesion-symptom mapping. As expected, CR acquisition was significantly reduced in cerebellar subjects compared to controls. Reduced CR acquisition was significantly more likely in participants with lesions of lobule VI and Crus I extending into Crus II (p<0.05, Liebermeister test). Cerebellar subjects could be subdivided into two groups: a smaller group (n=5) which showed acquisition, extinction and savings within the normal range; and a larger group (n=14) which did not show acquisition. In the latter, no conclusions on extinction or savings could be drawn. Previous findings were confirmed that circumscribed areas in lobule VI and Crus I are of major importance in CR acquisition. In addition, the present data suggest that if the critical regions of the cerebellar cortex are lesioned, the ability to acquire CRs is not only reduced but abolished. Subjects with lesions outside these critical areas, on the other hand show preserved acquisition, extinction and saving effects. As a consequence, studies in human subjects with cerebellar lesions do not allow drawing conclusions on CR extinction and savings. In light of the present findings, previous reports of reduced extinction in humans with circumscribed cerebellar disease need to be critically reevaluated. Copyright © 2016 Elsevier Ltd. All rights reserved.

Electronic structure of charge- and spin-controlled Sr(1-(x+y))La(x+y)Ti(1-x)Cr(x)O3.

PubMed

Iwasawa, H; Yamakawa, K; Saitoh, T; Inaba, J; Katsufuji, T; Higashiguchi, M; Shimada, K; Namatame, H; Taniguchi, M

2006-02-17

We present the electronic structure of Sr(1-(x+y))La(x+y)Ti(1-x)Cr(x)O3 investigated by high-resolution photoemission spectroscopy. In the vicinity of the Fermi level, it was found that the electronic structure was composed of a Cr 3d local state with the t(2g)3 configuration and a Ti 3d itinerant state. The energy levels of these Cr and Ti 3d states are well interpreted by the difference of the charge-transfer energy of both ions. The spectral weight of the Cr 3d state is completely proportional to the spin concentration x irrespective of the carrier concentration y, indicating that the spin density can be controlled by x as desired. In contrast, the spectral weight of the Ti 3d state is not proportional to y, depending on the amount of Cr doping.

Control of the electrical resistivity of Ni-Cr wires using low pressure chemical vapor deposition of tin

NASA Astrophysics Data System (ADS)

Kim, Jun-Hyun; Bak, Jeong Geun; Lee, Kangtaek; Kim, Chang-Koo

2018-01-01

Control of the electrical resistivity of Ni-Cr wires is demonstrated using low pressure chemical vapor deposition (LPCVD) of tin on the surface of the wire, after which the effects of the deposition temperature on the structural, morphological, and compositional characteristics of the tin-deposited Ni-Cr wires are investigated. As the deposition temperature is increased, the resistivity of the Ni-Cr wires increases in the temperature range 300-400 °C; then remains nearly constant as the temperature increased to 700 °C. The increase in the resistivity of the Ni-Cr wires is attributed to formation of Ni3Sn2 particulates on the surface of the wire. Compositional analysis shows that the pattern of change in the tin content with the deposition temperature is similar to that of resistivity with temperature, implying that the atomic content of tin on Ni-Cr directly affects the electrical resistivity.

Effect of applied strain on phase separation of Fe-28 at.% Cr alloy: 3D phase-field simulation

NASA Astrophysics Data System (ADS)

Zhu, Lihui; Li, Yongsheng; Liu, Chengwei; Chen, Shi; Shi, Shujing; Jin, Shengshun

2018-04-01

A quantitative simulation of the separation of the α‧ phase in Fe-28 at.% Cr alloy under the effects of applied strain is performed by utilizing a three-dimensional phase-field model. The elongation of the Cr-enriched α‧ phase becomes obvious with the influence of applied uniaxial strain for the phase separation transforms from spinodal decomposition of 700 K to nucleation and growth of 773 K. The applied strain shows a significant influence on the early stage phase separation, and the influence is enlarged with the elevated temperature. The steady-state coarsening with the mechanism of spinodal decomposition is substantially affected by the applied strain for low-temperature aging, while the influence is reduced as the temperature increases and as the phase separation mechanism changes to nucleation and growth. The peak value of particle size distribution decreases, and the PSD for 773 K becomes more widely influenced by the applied strain. The simulation results of separation of the Cr-enriched α‧ phase with the applied strain provide a further understanding of the strain effect on the phase separation of Fe-Cr alloys from the metastable region to spinodal regions.

Metabolite ratios to assumed stable creatine level may confound the quantification of proton brain MR spectroscopy.

PubMed

Li, Belinda S Y; Wang, Hao; Gonen, Oded

2003-10-01

In localized brain proton MR spectroscopy ((1)H-MRS), metabolites' levels are often expressed as ratios, rather than as absolute concentrations. Frequently, their denominator is the creatine [Cr], which level is explicitly assumed to be stable in normal as well as in many pathologic states. The rationale is that ratios self-correct for imager and localization method differences, gain instabilities, regional susceptibility variations and partial volume effects. The implicit assumption is that these benefits are worth their cost(w)-(w) propagation of the individual variation of each of the ratio's components. To test this hypothesis, absolute levels of N-acetylaspartate [NAA], choline [Cho] and [Cr] were quantified in various regions of the brains of 8 volunteers, using 3-dimensional (3D) (1)H-MRS at 1.5 T. The results show that in over 50% of approximately 2000 voxels examined, [NAA]/[Cr] and [Cho]/[Cr] exhibited higher coefficients of variations (CV) than [NAA] and [Cho] individually. Furthermore, in approximately 33% of these voxels, the ratios' CVs exceeded even the combined constituents' CVs. Consequently, basing metabolite quantification on ratios and assuming stable [Cr] introduces more variability into (1)H-MRS than it prevents. Therefore, its cost exceeds the benefit.

Chromium picolinate and chromium histidinate protects against renal dysfunction by modulation of NF-κB pathway in high-fat diet fed and Streptozotocin-induced diabetic rats.

PubMed

Selcuk, Mustafa Yavuz; Aygen, Bilge; Dogukan, Ayhan; Tuzcu, Zeynep; Akdemir, Fatih; Komorowski, James R; Atalay, Mustafa; Sahin, Kazim

2012-04-08

Diabetic nephropathy is one of major complications of diabetes mellitus. Although chromium is an essential element for carbohydrate and lipid metabolism, its effects on diabetic nephropathy are not well understood. The present study was conducted to investigate the effects of chromium picolinate (CrPic) and chromium histidinate (CrHis) on nuclear factor-kappa B (NF-κB) and nuclear factor-E2-related factor-2 (Nrf2) pathway in the rat kidney. Male Wistar rats were divided into six groups. Group I received a standard diet (8% fat) and served as a control; Group II was fed with a standard diet and received CrPic; Group III was fed with a standard diet and received CrHis; Group IV received a high fat diet (HFD, 40% fat) for 2 weeks and then were injected with streptozotocin (STZ) (HFD/STZ); Group V was treated as group IV (HFD/STZ) but supplemented with CrPic for 12 weeks. Group VI was treated as group IV (HFD/STZ) but supplemented with CrHis. The increased NF-κβ p65 in the HFD/STZ group was inhibited by CrPic and CrHis supplementation (P < 0.05). In STZ-treated rats, a significant decrease in levels of nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IκBα) was found in kidney tissues when compared to control rats (P < 0.05). A significant increase in the levels of IκBα was observed in CrPic- and CrHis-treated rats when compared with STZ-treated rats. Renal Nrf2 levels were significantly decreased in diabetic rats compared with the control rats. There was a higher tendency for increase of kidney Nrf2 level and decrease in kidney NFκBp65 levels and 4- hydroxyl nonenal (4-HNE) protein adducts (P < 0.05) in diabetic rats. Our result show that in kidney tissue CrHis/CrPic increases Nrf2 level, parallelly decreases NF-κB and partially restores IκBα levels in HFD/STZ group, suggesting that CrPic and CrHis may play a role in antioxidant defense system via the Nrf2 pathway by reducing inflammation through NF-κβ p65 inhibition. Moreover, a greater reduction in NF-κB expression and greater increases in expressions of IκBα and Nrf2 in diabetic rats supplemented with CrHis than rats supplemented with CrPic suggest that CrHis has more favorable effects than CrPic.

Effect of chromium supplementation on glycated hemoglobin and fasting plasma glucose in patients with diabetes mellitus.

PubMed

Yin, Raynold V; Phung, Olivia J

2015-02-13

Chromium (Cr) is a trace element involved in glucose homeostasis. We aim to evaluate and quantify the effects of Cr supplementation on A1C and FPG in patients with T2DM. A systematic literature search of Pubmed, EMBASE and the Cochrane Library (from database inception to 11/2014) with no language restrictions sought RCTs or cohort studies evaluating Cr supplementation in T2DM vs control and reporting either change in glycated hemoglobin (A1C) or fasting plasma glucose (FPG). Meta-analysis was conducted on each subtype of Cr supplement separately, and was analyzed by random effects model to yield the weighted mean differences (WMD) and 95% confidence intervals (CIs). Heterogeneity was assessed by using the I(2) statistic. A total of 14 RCTs (n=875 participants, mean age range: 30 to 83 years old, 8 to 24 weeks of follow-up) were identified (Cr chloride: n=3 study, Cr picolinate: n=5 study, brewer's yeast: n=4 study and Cr yeast: n=3 study). Compared with placebo, Cr yeast, brewer's yeast and Cr picolinate did not show statistically significant effects on A1C. Furthermore, compared to control, Cr chloride, Cr yeast and Cr picolinate showed no effect on FPG, however, brewer's yeast showed a statistically significant decrease in FPG -19.23 mg/dL (95% CI=-35.30 to -3.16, I(2)=21%, n=137). Cr supplementation with brewer's yeast may provide marginal benefits in lowering FPG in patients with T2DM compared to placebo however it did not have any effect on A1C.

Self-Rated Communication-Related Quality of Life of Individuals With Oromandibular Dystonia Receiving Botulinum Toxin Injections.

PubMed

Page, Allyson D; Siegel, Lauren; Jog, Mandar

2017-06-22

In this preliminary study, we examined self-rated communication-related quality of life (CR-QoL) of 10 control participants and 10 individuals with oromandibular dystonia (OMD) and dysarthria receiving therapeutic botulinum toxin (BoNT-A) injections. Participants with OMD and associated dysarthria self-rated CR-QoL pre- and post- BoNT-A injection using the American Speech-Language-Hearing Association's Quality of Communication Life Scale (ASHA QCL; Paul et al., 2004). Control participants self-rated CR-QoL during a single experimental visit. Significant differences were found between control participants and participants with OMD on ratings of CR-QoL across all 5 domains and subdomains of the ASHA QCL. No significant differences in CR-QoL were found over the course of the BoNT-A treatment cycle. CR-QoL was rated lower by participants with OMD as compared with control participants across all ASHA QCL domains/subdomains with "socialization/activities" and "confidence/self-concept" having the largest effect sizes. No differences in CR-QoL were found over the course of the treatment cycle. We advocate for outcome measures that include patient report. The use of patient-reported outcome measures in conjunction with objective or impairment-based outcome measures can help inform meaningful clinical indicators of treatment success. This study adds novel information that may aid our understanding of the experience of living with OMD in this underserviced clinical population.

Magnetic and magnetocaloric properties of Ni-Mn-Cr-Sn Heusler alloys under the effects of hydrostatic pressure

NASA Astrophysics Data System (ADS)

Pandey, Sudip; Us Saleheen, Ahmad; Quetz, Abdiel; Chen, Jing-Han; Aryal, Anil; Dubenko, Igor; Stadler, Shane; Ali, Naushad

2018-05-01

The magnetic, thermal, and magnetocaloric properties of Ni45Mn43CrSn11 Heusler alloy have been investigated using differential scanning calorimetry and magnetization with hydrostatic pressure measurements. A shift in the martensitic transition temperature (TM) to higher temperatures was observed with the application of pressure. The application of pressure stabilizes the martensitic state and demonstrated that pressure can be a parameter used to control and tune the martensitic transition temperature (the temperature where the largest magnetocaloric effect is observed). The magnetic entropy change significantly decreases from 33 J/kg K to 16 J/kg K under the application of a hydrostatic pressure of 0.95 GPa. The critical field of the direct metamagnetic transition increases, whereas the initial susceptibility (dM/dH) in the low magnetic field region drastically decreases with increasing pressure. The relevant parameters that affect the magnetocaloric properties are discussed.

The functional connectome of cognitive reserve

PubMed Central

Marques, Paulo; Moreira, Pedro; Magalhães, Ricardo; Costa, Patrício; Santos, Nadine; Zihl, Josef; Soares, José

2016-01-01

Abstract Cognitive Reserve (CR) designates the brain's capacity to actively cope with insults through a more efficient use of its resources/networks. It was proposed in order to explain the discrepancies between the observed cognitive ability and the expected capacity for an individual. Typical proxies of CR include education and Intelligence Quotient but none totally account for the variability of CR and no study has shown if the brain's greater efficiency associated with CR can be measured. We used a validated model to estimate CR from the residual variance in memory and general executive functioning, accounting for both brain anatomical (i.e., gray matter and white matter signal abnormalities volume) and demographic variables (i.e., years of formal education and sex). Functional connectivity (FC) networks and topological properties were explored for associations with CR. Demographic characteristics, mainly accounted by years of formal education, were associated with higher FC, clustering, local efficiency and strength in parietal and occipital regions and greater network transitivity. Higher CR was associated with a greater FC, local efficiency and clustering of occipital regions, strength and centrality of the inferior temporal gyrus and higher global efficiency. Altogether, these findings suggest that education may facilitate the brain's ability to form segregated functional groups, reinforcing the view that higher education level triggers more specialized use of neural processing. Additionally, this study demonstrated for the first time that CR is associated with more efficient processing of information in the human brain and reinforces the existence of a fine balance between segregation and integration. Hum Brain Mapp 37:3310–3322, 2016.. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc. PMID:27144904

Ultrasonography has a diagnostic value in the assessment of cervical radiculopathy: A prospective pilot study.

PubMed

Takeuchi, Mikinobu; Wakao, Norimitsu; Hirasawa, Atsuhiko; Murotani, Kenta; Kamiya, Mitsuhiro; Osuka, Koji; Takayasu, Masakazu

2017-08-01

This study investigated the diagnostic accuracy of the difference in the cross-sectional areas (CSAs) of affected cervical nerve roots (NRs) for diagnosing cervical radiculopathy (CR). In total, 102 CR patients and 219 healthy volunteers were examined with ultrasound. The CSA of the cervical NR at each level was measured on the affected side and the contralateral side in CR patients by blinded ultrasonographic technicians. The difference between the CSAs of CR patients and normal volunteers and the difference in the laterality of CSA at the same affected level (ΔCSA) were calculated for each cervical level. The CSAs of the affected NRs in CR patients were significantly larger than those of the unaffected NRs in CR patients and those of the control group at the C5, C6 and C7 levels (P<0.005). ΔCSA was also significantly larger in the CR group at all levels (P<0.001). A receiver operating characteristic analysis demonstrated that the threshold values were 9.6 mm 2 (CSA) for C5NR and 15 mm 2 for both C6NR and C7NR. This study revealed that the CSAs of affected NRs were enlarged and that the laterality of the CSA (ΔCSA) was greater in CR patients than in control patients. • Cervical radiculopathy is diagnosed through ultrasonographic measurement of the CSAs. • The CSAs of affected nerve roots were significantly enlarged. • The ΔCSA in the CR group was significantly higher than in the control group. • Diagnostic CSA and ΔCSA thresholds were identified.

Cancer mortality in a Chinese population exposed to hexavalent chromium in drinking water

USGS Publications Warehouse

Beaumont, J.J.; Sedman, R.M.; Reynolds, S.D.; Sherman, C.D.; Li, L.-H.; Howd, R.A.; Sandy, M.S.; Zeise, L.; Alexeeff, G.V.

2008-01-01

BACKGROUND: In 1987, investigators in Liaoning Province, China, reported that mortality rates for all cancer, stomach cancer, and lung cancer in 1970-1978 were higher in villages with hexavalent chromium (Cr)-contaminated drinking water than in the general population. The investigators reported rates, but did not report statistical measures of association or precision. METHODS: Using reports and other communications from investigators at the local Jinzhou Health and Anti-Epidemic Station, we obtained data on Cr contamination of groundwater and cancer mortality in 9 study regions near a ferrochromium factory. We estimated:(1) person-years at risk in the study regions, based on census and population growth rate data, (2) mortality counts, based on estimated person-years at risk and previously reported mortality rates, and (3) rate ratios and 95% confidence intervals. RESULTS: The all-cancer mortality rate in the combined 5 study regions with Cr-contaminated water was negligibly elevated in comparison with the rate in the 4 combined study regions without contaminated water (rate ratio = 1.13; 95% confidence interval = 0.86-1.46), but was somewhat more elevated in comparison with the whole province (1.23; 0.97-1.53). Stomach cancer mortality in the regions with contaminated water was more substantially elevated in comparison with the regions without contaminated water (1.82; 1.11-2.91) and the whole province (1.69; 1.12-2.44). Lung cancer mortality was slightly elevated in comparison with the unexposed study regions (1.15; 0.62-2.07), and more strongly elevated in comparison with the whole province (1.78; 1.03-2.87). Mortality from other cancers combined was not elevated in comparison with either the unexposed study regions (0.86; 0.53-1.36) or the whole province (0.92; 0.58-1.38). CONCLUSIONS: While these data are limited, they are consistent with increased stomach cancer risk in a population exposed to Cr in drinking water. ?? 2008 Lippincott Williams & Wilkins, Inc.

Quantitative energy-filtered TEM imaging of interfaces

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bentley, J.; Kenik, E.A.; Siangchaew, K.

Quantitative elemental mapping by inner shell core-loss energy-filtered transmission electron microscopy (TEM) with a Gatan Imaging Filter (GIF) interfaced to a Philips CM30 TEM operated with a LaB{sub 6} filament at 300 kV has been applied to interfaces in a range of materials. In sensitized type 304L stainless steel aged 15 h at 600{degrees}C, grain-boundary Cr depletion occurs between Cr-rich intergranular M{sub 23}C{sub 6} particles. Images of net Cr L{sub 23} intensity show segregation profiles that agree quantitatively with focused-probe spectrum-line measurements recorded with a Gatan PEELS on a Philips EM400T/FEG (0.8 nA in 2-nm-diam probe) of the same regions.more » Rare-earth oxide additives that are used for the liquid-phase sintering of Si{sub 3}N{sub 4} generate second phases of complex composition at grain boundaries and edges. These grain boundary phases often control corrosion, crack growth and creep damage behavior. High resolution imaging has been widely and with focused probes can be compromised by beam damage, but elemental mapping by EFTEM appears not to cause appreciable beam damage.« less

Structural and motional contributions of the Bacillus subtilis ClpC N-domain in adaptor protein interactions

PubMed Central

Kojetin, Douglas J.; McLaughlin, Patrick D.; Thompson, Richele J.; Dubnau, David; Prepiak, Peter; Rance, Mark; Cavanagh, John

2009-01-01

Summary The AAA+ superfamily protein ClpC is a key regulator of cell development in Bacillus subtilis. As part of a large oligomeric complex, ClpC controls an array of cellular processes by recognizing, unfolding, and providing misfolded and aggregated proteins as substrates for the ClpP peptidase. ClpC is unique compared to other HSP100/Clp proteins, as it requires an adaptor protein for all fundamental activities. The NMR solution structure of the N-terminal repeat domain of ClpC (N-ClpCR) comprises two structural repeats of a four-helix motif. NMR experiments used to map the MecA adaptor protein interaction surface of N-ClpCR reveal that regions involved in the interaction possess conformational flexibility, as well as conformational exchange on the μs-ms time-scale. The electrostatic surface of N-ClpCR differs substantially compared to the N-domain of Escherichia coli ClpA and ClpB, suggesting that the electrostatic surface characteristics of HSP100/Clp N-domains may play a role in adaptor protein and substrate interaction specificity, and perhaps contribute to the unique adaptor protein requirement of ClpC. PMID:19361434

Mini-midi-mito: adapting the amplification and sequencing strategy of mtDNA to the degradation state of crime scene samples.

PubMed

Berger, Cordula; Parson, Walther

2009-06-01

The degradation state of some biological traces recovered from the crime scene requires the amplification of very short fragments to attain a useful mitochondrial (mt)DNA sequence. We have previously introduced two mini-multiplex assays that amplify 10 overlapping control region (CR) fragments in two separate multiplex PCRs, which brought successful CR consensus sequences from even highly degraded DNA extracts. This procedure requires a total of 20 sequencing reactions per sample, which is laborious and cost intensive. For only moderately degraded samples that we encounter more frequently with typical mtDNA casework material, we developed two new multiplex assays that use a subset of the mini-amplicon primers but embrace larger fragments (midis) and require only 10 sequencing reactions to build a double-stranded CR consensus sequence. We used a preceding mtDNA quantitation step by real-time PCR with two different target fragments (143 and 283 bp) that roughly correspond to the average fragment sizes of the different multiplex approaches to estimate size-dependent mtDNA quantities and to aid the choice of the appropriate PCR multiplexes with respect to quality of the results and required costs.

Proton magnetic resonance spectroscopic findings of cerebral fat embolism induced by triolein emulsion in cats.

PubMed

Baik, S K; Kim, Y-W; Kim, H J; Lee, J W; Cho, B M; Kim, D-H; Choi, S H; Lee, S H; Chang, K H

2008-12-01

In experimental studies, embolization of the cerebral hemisphere with triolein emulsion has revealed reversible magnetic resonance imaging (MRI) findings in the subacute stage. To investigate the changes in the major metabolites, by proton magnetic resonance spectroscopy (MRS), in a cerebral fat embolism induced by a triolein emulsion. The internal carotid arteries of 19 cats were injected with a triolein emulsion, and multivoxel MRS was performed 30 min, 1 day, and 7 days later. In the control group, six cats were injected with normal saline. The MR spectra were evaluated for N-acetyl aspartate (NAA), creatine (Cr), and choline (Cho), along with the presence of lipid and lactate. Semiquantitative analyses of NAA/Cr, Cho/Cr, NAA/Cho, and lipid/Cr ratios compared the median values of the ipsilateral metabolite ratios with those of the contralateral side and in the control group for each point in time. The NAA/Cr, Cho/Cr, and NAA/Cho ratios in the ipsilateral cerebral hemisphere of the embolized group after 30 min, 1 day, and 7days were not significantly different from the contralateral hemisphere of the embolized and control groups (P>0.05). The lipid/Cr ratio in the ipsilateral cerebral hemisphere of the embolized group was significantly higher when compared with the control group (P=0.012 at 30 min, P=0.001 on day 1, and P=0.018 on day 7). Cerebral fat embolism induced by a triolein emulsion resulted in no significant change in the major metabolites of the brain in the acute stage, except for an elevated lipid/Cr ratio, which suggests the absence of any significant hypoxic-ischemic changes in the lesions embolized using a fat emulsion.

A molecular phylogeny of anseriformes based on mitochondrial DNA analysis.

PubMed

Donne-Goussé, Carole; Laudet, Vincent; Hänni, Catherine

2002-06-01

To study the phylogenetic relationships among Anseriformes, sequences for the complete mitochondrial control region (CR) were determined from 45 waterfowl representing 24 genera, i.e., half of the existing genera. To confirm the results based on CR analysis we also analyzed representative species based on two mitochondrial protein-coding genes, cytochrome b (cytb) and NADH dehydrogenase subunit 2 (ND2). These data allowed us to construct a robust phylogeny of the Anseriformes and to compare it with existing phylogenies based on morphological or molecular data. Chauna and Dendrocygna were identified as early offshoots of the Anseriformes. All the remaining taxa fell into two clades that correspond to the two subfamilies Anatinae and Anserinae. Within Anserinae Branta and Anser cluster together, whereas Coscoroba, Cygnus, and Cereopsis form a relatively weak clade with Cygnus diverging first. Five clades are clearly recognizable among Anatinae: (i) the Anatini with Anas and Lophonetta; (ii) the Aythyini with Aythya and Netta; (iii) the Cairinini with Cairina and Aix; (iv) the Mergini with Mergus, Bucephala, Melanitta, Callonetta, Somateria, and Clangula, and (v) the Tadornini with Tadorna, Chloephaga, and Alopochen. The Tadornini diverged early on from the Anatinae; then the Mergini and a large group that comprises the Anatini, Aythyini, Cairinini, and two isolated genera, Chenonetta and Marmaronetta, diverged. The phylogeny obtained with the control region appears more robust than the one obtained with mitochondrial protein-coding genes such as ND2 and cytb. This suggests that the CR is a powerful tool for bird phylogeny, not only at a small scale (i.e., relationships between species) but also at the family level. Whereas morphological analysis effectively resolved the split between Anatinae and Anserinae and the existence of some of the clades, the precise composition of the clades are different when morphological and molecular data are compared. (c) 2002 Elsevier Science (USA).

Early Pliocene Hiatus in Sand Output by the Colorado River: Evidence From Marine Deposits in the Salton Trough, Southern California

NASA Astrophysics Data System (ADS)

Dorsey, R. J.; Bykerk-Kauffman, A.

2015-12-01

Early Pliocene deposits in the western Salton Trough preserve a high-fidelity record of sediment dispersal into the marine realm during initiation and early evolution of the Colorado River (CR). Grain-size fractionation, sediment routing, and transport dynamics of the early CR delta are recorded in sediments of the Fish Creek - Vallecito basin, which was located ~100 km south of Yuma along the transform plate boundary at 5 Ma. Early Pliocene delivery of CR sand to the basin took place in two distinct pulses: (1) deposition of sandy turbidites (Wind Caves Mbr of the Latrania Fm) in a restricted submarine canyon at Split Mt Gorge between ~5.3 and 5.1 Ma; and (2) progradation of a thick, widespread, coarsening-up deltaic sequence of marine mudstone, sandstone, and coquinas (Deguynos Fm) between ~4.8 and 4.2 Ma. Estimated flux of CR sediment during Wind Caves deposition was weak (~3-5 Mt/yr) compared to the long-term average (172±64 Mt/yr). The two pulses of CR sand input are separated by the Coyote Clay (CC, ~5.1-4.8 Ma), a regionally correlable, greenish-yellow-weathering marine claystone unit at the base of the Deguynos Fm. CC gradationally overlies Wind Caves turbidites in the area of the paleocanyon. In contrast, in the Coyote Mts 15-23 km to the south and SE, CC rests on coarse-grained locally-derived late Miocene sedimentary rocks, Alverson volcanics, and metamorphic basement rock along a regional unconformity. Identical claystone facies occur in the NW Indio Hills (restores to Yuma at the mouth of the CR at 5 Ma), and Sierra Cucapa in Mexico (~200 km south of Yuma at 5 Ma). Marine localities outside of the Wind Caves paleocanyon experienced slow to negligible sedimentation along a rugged rocky shoreline until abrupt arrival of CR-derived clay. CC accumulated in a sand-starved, pro-delta marine setting (Winker, 1987) over an inferred N-S distance of ~200 km. We therefore reject an alternate hypothesis that CC accumulated on the muddy slope of the prograding CR delta (Cloos, 2014). The CC records a pronounced 200-300 Kyr hiatus in delivery of sand from the CR to the basin at ca. 5 Ma that requires a regional explanation. The hiatus could have been caused by (1) global sea-level rise, (2) accelerated basin subsidence, or (3) tectonic damming and ponding of the lower CR by fault-related bedrock uplift in the Chocolate Mts.

Screening for chronic kidney disease of uncertain aetiology in Sri Lanka: usability of surrogate biomarkers over dipstick proteinuria.

PubMed

Ratnayake, Samantha; Badurdeen, Zeid; Nanayakkara, Nishantha; Abeysekara, Tilak; Ratnatunga, Neelakanthi; Kumarasiri, Ranjith

2017-06-19

The use of dipstick proteinuria to screen Chronic Kidney Disease of uncertain aetiology (CKDu) in Sri Lanka is a recently debated matter of dispute. The aim of this study was to assess the suitability of biomarkers: serum creatinine, cystatin C and urine albumin to creatinine ratio (ACR) for screening CKDu in Sri Lanka. Forty-four male CKDu patients and 49 healthy males from a CKDu-endemic region were selected. Meanwhile, 25 healthy males from a non-endemic region were selected as an absolute control. The diagnostic accuracy of each marker was compared using the above three study groups. In receiver operating characteristics (ROC) plots for creatinine, cystatin C and ACR, values of area under the curve (AUC) were 0.926, 0.920 and 0.737 respectively when CKDu was compared to non-endemic control. When CKDu was compared to endemic control, AUCs of above three analytes were distinctly lower as 0.718, 0.808 and 0.678 respectively. Cystatin C exhibited the highest sensitivity for CKDu when analyzed against both control groups where respective sensitivities were 0.75 against endemic control and 0.89 against non-endemic control. ROC-optimal cutoff limits of creatinine, cystatin C and ACR in CKDu vs non-endemic control were 89.0 μmol/L, 1.01 mg/L and 6.06 mg/g-Cr respectively, whereas in CKDu vs endemic control the respective values were 111.5 μmol/L, 1.22 mg/L and 12.66 mg/g-Cr. Amongst the three biomarkers evaluated in this study, our data suggest that Cystatin C is the most accurate functional marker in detecting CKDu in endemic regions, yet the high cost hinders its usability on general population. Creatinine is favorable over dipstick proteinuria owing to its apparent accuracy and cost efficiency, while having the ability to complement the kidney damage marker (ACR) in screening. ACR may not be favorable as a standalone screening marker in place of dipstick proteinuria due to its significant decline in sensitivity against the CKDu-endemic population. However, creatinine and ACR in a complementary manner could overcome current shortcomings of dipstick proteinuria and such a dual marker tool could be commodious in screening CKDu-type tubulointerstital diseases. Furthermore, use of ACR may also increase the ability to clinically discriminate CKDu from other glomerular nephropathies.

Accelerated redox reaction between chromate and phenolic pollutants during freezing.

PubMed

Ju, Jinjung; Kim, Jaesung; Vetráková, Ľubica; Seo, Jiwon; Heger, Dominik; Lee, Changha; Yoon, Ho-Il; Kim, Kitae; Kim, Jungwon

2017-05-05

The redox reaction between 4-chlorophenol (4-CP) and chromate (Cr(VI)) (i.e., the simultaneous oxidation of 4-CP by Cr(VI) and reduction of Cr(VI) by 4-CP) in ice (i.e., at -20°C) was compared with the corresponding reaction in water (i.e., at 25°C). The redox conversion of 4-CP/Cr(VI), which was negligible in water, was significantly accelerated in ice. This accelerated redox conversion of 4-CP/Cr(VI) in ice is ascribed to the freeze concentration effect occurring during freezing, which excludes solutes (i.e., 4-CP and Cr(VI)) and protons from the ice crystals and subsequently concentrates them in the liquid brine. The concentrations of Cr(VI) and protons in the liquid brine were confirmed by measuring the optical image and the UV-vis absorption spectra of cresol red (CR) as a pH indicator of frozen solution. The redox conversion of 4-CP/Cr(VI) was observed in water when the concentrations of 4-CP/protons or Cr(VI)/protons increased by 100/1000-fold. These results corroborate the freeze concentration effect as the reason for the accelerated redox conversion of 4-CP/Cr(VI) in ice. The redox conversion of various phenolic pollutants/Cr(VI) and 4-CP/Cr(VI) in real wastewater was successfully achieved in ice, which verifies the environmental relevance and importance of freezing-accelerated redox conversion of phenolic pollutants/Cr(VI) in cold regions. Copyright © 2017 Elsevier B.V. All rights reserved.

Stress distribution in Co-Cr implant frameworks after laser or TIG welding.

PubMed

de Castro, Gabriela Cassaro; de Araújo, Cleudmar Amaral; Mesquita, Marcelo Ferraz; Consani, Rafael Leonardo Xediek; Nóbilo, Mauro Antônio de Arruda

2013-01-01

Lack of passivity has been associated with biomechanical problems in implant-supported prosthesis. The aim of this study was to evaluate the passivity of three techniques to fabricate an implant framework from a Co-Cr alloy by photoelasticity. The model was obtained from a steel die simulating an edentulous mandible with 4 external hexagon analog implants with a standard platform. On this model, five frameworks were fabricated for each group: a monoblock framework (control), laser and TIG welding frameworks. The photoelastic model was made from a flexible epoxy resin. On the photoelastic analysis, the frameworks were bolted onto the model for the verification of maximum shear stress at 34 selected points around the implants and 5 points in the middle of the model. The stresses were compared all over the photoelastic model, between the right, left, and center regions and between the cervical and apical regions. The values were subjected to two-way ANOVA, and Tukey's test (α=0.05). There was no significant difference among the groups and studied areas (p>0.05). It was concluded that the stresses generated around the implants were similar for all techniques.

Effects of chromium-enriched bacillus subtilis KT260179 supplementation on chicken growth performance, plasma lipid parameters, tissue chromium levels, cecal bacterial composition and breast meat quality.

PubMed

Yang, Jiajun; Qian, Kun; Zhang, Wei; Xu, Yayuan; Wu, Yijing

2016-11-08

Both chromium (Cr) and probiotic bacillus own the virtues of regulating animal metabolism and meat quality. Purpose of this study was to evaluate the efficiency of supplemental Cr and bacillus in the form of chromium-enriched Bacillus subtilis KT260179 (CEBS) on chicken growth performance, plasma lipid parameters, tissue chromium levels, cecal bacterial composition and breast meat quality. Six hundred of 1-day-old Chinese Huainan Partridge chickens were divided into four groups randomly: Control, inorganic Cr, Bacillus subtilis, and CEBS. The feed duration was 56 days. After 28 days of treatment, broiler feed CEBS or normal B. subtilis had higher body weights than control broiler, and after 56 days, chickens given either CEBS or B. subtilis had greater body weights than control broiler or those given inorganic Cr. Plasma total cholesterol, triglycerides, and low density lipoprotein cholesterol levels declined significantly in the CEBS group compared with the control, whereas plasma high density lipoprotein cholesterol levels increased significantly. The concentration of Cr in blood and breast muscle increased after CEBS and inorganic Cr supplementation. B. subtilis and CEBS supplementation caused a significant increase in the numbers of Lactobacillus and Bifidobacterium in the caecum, while the numbers of Escherichia coli and Salmonella decreased significantly compared to the control. Feed adding CEBS increased the lightness, redness, and yellowness of breast meat, improved the water-holding capacity, decreased the shear force and cooking loss. In all, CEBS supplementation promoted body growth, improved plasma lipid parameters, increased tissue Cr concentrations, altered cecal bacterial composition and improved breast meat quality.

Oxygen Costs of the Incremental Shuttle Walk Test in Cardiac Rehabilitation Participants: An Historical and Contemporary Analysis.

PubMed

Buckley, John P; Cardoso, Fernando M F; Birkett, Stefan T; Sandercock, Gavin R H

2016-12-01

The incremental shuttle walk test (ISWT) is a standardised assessment for cardiac rehabilitation. Three studies have reported oxygen costs (VO 2 )/metabolic equivalents (METs) of the ISWT. In spite of classic representations from these studies graphically showing curvilinear VO 2 responses to incremented walking speeds, linear regression techniques (also used by the American College of Sports Medicine [ACSM]) have been used to estimate VO 2 . The two main aims of this study were to (i) resolve currently reported discrepancies in the ISWT VO 2 -walking speed relationship, and (ii) derive an appropriate VO 2 versus walking speed regression equation. VO 2 was measured continuously during an ISWT in 32 coronary heart disease [cardiac] rehabilitation (CHD-CR) participants and 30 age-matched controls. Both CHD-CR and control group VO 2 responses were curvilinear in nature. For CHD-CR VO 2  = 4.4e 0.23 × walkingspeed (km/h) . The integrated area under the curve (iAUC) VO 2 across nine ISWT stages was greater in the CHD-CR group versus the control group (p < 0.001): CHD-CR = 423 (±86) ml·kg -1 ·min -1 ·km·h -1 ; control = 316 (±52) ml·kg -1 ·min -1 ·km·h -1 . CHD-CR group vs. control VO 2 was up to 30 % greater at higher ISWT stages. The curvilinear nature of VO 2 responses during the ISWT concur with classic studies reported over 100 years. VO 2 estimates for walking using linear regression models (including the ACSM) clearly underestimate values in healthy and CHD-CR participants, and this study provides a resolution to this when the ISWT is used for CHD-CR populations.

Trace element control in binary Ni-25Cr and ternary Ni-30Co-30Cr master alloy castings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Detrois, Martin; Jablonski, Paul D.

Electro-slag remelting (ESR) is used for control of unwanted elements in commercial alloys. This study focuses on master alloys of Ni-25Cr and Ni-30Co-30Cr, processed through a combination of vacuum induction melting (VIM) and electro-slag remelting (ESR). Minor additions were made to control tramp element levels and modify the melting characteristics. Nitrogen and sulfur levels below 10 ppm and oxygen levels below 100 ppm were obtained in the final products. The role of the alloy additions in lowering the tramp element content, the resulting residual inclusions and the melting characteristics were determined computationally and confirmed experimentally. Additions of titanium were beneficialmore » to the control of oxygen levels during VIM and nitrogen levels during ESR. Aluminum additions helped to control oxygen levels during remelting, however, aluminum pickup occurred when excess titanium was present during ESR. The usefulness of these master alloys for use as experimental remelt stock will also be discussed.« less

CT radiation profile width measurement using CR imaging plate raw data

PubMed Central

Yang, Chang‐Ying Joseph

2015-01-01

This technical note demonstrates computed tomography (CT) radiation profile measurement using computed radiography (CR) imaging plate raw data showing it is possible to perform the CT collimation width measurement using a single scan without saturating the imaging plate. Previously described methods require careful adjustments to the CR reader settings in order to avoid signal clipping in the CR processed image. CT radiation profile measurements were taken as part of routine quality control on 14 CT scanners from four vendors. CR cassettes were placed on the CT scanner bed, raised to isocenter, and leveled. Axial scans were taken at all available collimations, advancing the cassette for each scan. The CR plates were processed and raw CR data were analyzed using MATLAB scripts to measure collimation widths. The raw data approach was compared with previously established methodology. The quality control analysis scripts are released as open source using creative commons licensing. A log‐linear relationship was found between raw pixel value and air kerma, and raw data collimation width measurements were in agreement with CR‐processed, bit‐reduced data, using previously described methodology. The raw data approach, with intrinsically wider dynamic range, allows improved measurement flexibility and precision. As a result, we demonstrate a methodology for CT collimation width measurements using a single CT scan and without the need for CR scanning parameter adjustments which is more convenient for routine quality control work. PACS numbers: 87.57.Q‐, 87.59.bd, 87.57.uq PMID:26699559

Portable air pollution control equipment for the control of toxic particulate emissions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chaurushia, A.; Odabashian, S.; Busch, E.

1997-12-31

Chromium VI (Cr VI) has been identified by the environmental regulatory agencies as a potent carcinogen among eleven heavy metals. A threshold level of 0.0001 lb/year for Cr VI emissions has been established by the California Air Resources Board for reporting under Assembly Bill 2588. A need for an innovative control technology to reduce fugitive emissions of Cr VI was identified during the Air Toxic Emissions Reduction Program at Northrop Grumman Military Aircraft Systems Division (NGMASD). NGMASD operates an aircraft assembly facility in El Segundo, CA. Nearly all of the aircraft components are coated with a protective coating (primer) priormore » to assembly. The primer has Cr VI as a component for its excellent corrosion resistance property. The complex assembly process requires fasteners which also need primer coating. Therefore, NGMASD utilizes High Volume Low Pressure (HVLP) guns for the touch-up spray coating operations. During the touch-up spray coating operations, Cr VI particles are atomized and transferred to the aircraft surface. The South Coast Air Quality Management District (SCAQMD) has determined that the HVLP gun transfers 65% of the paint particles onto the substrate and the remaining 35% are emitted as an overspray if air pollution controls are not applied. NGMASD has developed the Portable Air Pollution Control Equipment (PAPCE) to capture and control the overspray in order to reduce fugitive Cr VI emissions from the touch-up spray coating operations. A source test was performed per SCAQMD guidelines and the final report has been approved by the SCAQMD.« less

Fine structure of Fe-Co-Ga and Fe-Cr-Ga alloys with low Ga content

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kleinerman, Nadezhda M., E-mail: kleinerman@imp.uran.ru; Serikov, Vadim V., E-mail: kleinerman@imp.uran.ru; Vershinin, Aleksandr V., E-mail: kleinerman@imp.uran.ru

2014-10-27

Investigation of Ga influence on the structure of Fe-Cr and Fe-Co alloys was performed with the use of {sup 57}Fe Mössbauer spectroscopy and X-ray diffraction methods. In the alloys of the Fe-Cr system, doping with Ga handicaps the decomposition of solid solutions, observed in the binary alloys, and increases its stability. In the alloys with Co, Ga also favors the uniformity of solid solutions. The analysis of Mössbauer experiments gives some grounds to conclude that if, owing to liquation, clusterization, or initial stages of phase separation, there exist regions enriched in iron, some amount of Ga atoms prefer to entermore » the nearest surroundings of iron atoms, thus forming binary Fe-Ga regions (or phases)« less

CARE CR-Cardiovascular and cardiorespiratory Adaptations to Routine Exercise-based Cardiac Rehabilitation: a study protocol for a community-based controlled study with criterion methods.

PubMed

Nichols, Simon; Nation, Fiona; Goodman, Toni; Clark, Andrew L; Carroll, Sean; Ingle, Lee

2018-01-27

Cardiac rehabilitation (CR) reduces all-cause and cardiovascular mortality in patients with coronary heart disease (CHD). Much of this improvement has been attributed to the beneficial effects of structured exercise training. However, UK-based studies have not confirmed this. Improvements in survival and cardiovascular health are associated with concurrent improvements in cardiorespiratory fitness (CRF). It is therefore concerning that estimated CRF improvements resulting from UK-based CR are approximately one-third of those reported in international literature. Modest improvements in CRF suggest that UK CR exercise training programmes may require optimisation if long-term survival is to be improved. However, contemporary UK studies lack control data or use estimates of CRF change. Cardiovascular and cardiorespiratory Adaptations to Routine Exercise-based CR is a longitudinal, observational, controlled study designed to assess the short-term and long-term effect of CR on CRF, as well cardiovascular and cardiometabolic health. Patients will be recruited following referral to their local CR programme and will either participate in a routine, low-to-moderate intensity, 8-week (16 sessions) exercise-based CR programme or freely abstain from supervised exercise. Initial assessment will be conducted prior to exercise training, or approximately 2 weeks after referral to CR if exercise training is declined. Reassessment will coincide with completion of exercise training or 10 weeks after initial assessment for control participants. Participants will receive a final follow-up 12 months after recruitment. The primary outcome will be peak oxygen consumption determined using maximal cardiopulmonary exercise testing. Secondary outcomes will include changes in subclinical atherosclerosis (carotid intima-media thickness and plaque characteristics), body composition (dual X-ray absorptiometry) and cardiometabolic biomarkers. Ethical approval for this non-randomised controlled study has been obtained from the Humber Bridge NHS Research Ethics Committee-Yorkshire and the Humber on the 27th September 2013, (12/YH/0278). Results will be presented at national conferences and published in peer-reviewed journals. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Role of fractalkine/CX3CR1 signaling pathway in the recovery of neurological function after early ischemic stroke in a rat model.

PubMed

Liu, Yan-Zhi; Wang, Chun; Wang, Qian; Lin, Yong-Zhong; Ge, Yu-Song; Li, Dong-Mei; Mao, Geng-Sheng

2017-09-01

This study aims to explore the role of fractalkine/CX3C chemokine receptor 1 (CX3CR1) signaling pathway in the recovery of neurological functioning after an early ischemic stroke in rats. After establishment of permanent middle cerebral artery occlusion (pMCAO) models, 50 rats were divided into blank, sham, model, positive control and CX3CR1 inhibitor groups. Neurological impairment, walking and grip abilities, and cortical and hippocampal infarctions were evaluated by Zea Longa scoring criterion, beam-walking assay and grip strength test, and diffusion-weighted magnetic resonance imaging. qRT-PCR and Western blotting were performed to detect mRNA and protein expressions. ELISA was conducted to measure concentration of sFractalkine (sFkn), interleukin-1β (IL-1β) and TNF-α. The recovery rate of neurological functioning impairment and reduced walking and grip abilities was faster in the positive control and CX3CR1 inhibitor groups than the model group. The model, positive control and CX3CR1 inhibitor groups showed increased mRNA and protein expression of chemokine C-X3-C motif ligand 1 (CX3CL1) and CX3CR1, concentration of sFkn, IL-1β and TNF-α, and size of cortical and cerebral infarctions while decreased expression of NGF and BDNF compared with the blank and sham groups. Compared with the model group, the mRNA and protein expression of CX3CL1 and CX3CR1, concentration of sFkn, IL-1β and TNF-α, and size of cortical and cerebral infarctions decreased while expression of NGF and BDNF increased in the positive control and CX3CR1 inhibitor groups. Thus, the study suggests that inhibition of fractalkine/CX3CR1 signaling pathway promotes the recovery of neurological functioning after the occurrence of an early ischemic stroke. Copyright © 2017 Elsevier Inc. All rights reserved.

Thermobarometric constraints on mid-Cretaceous to late Cretaceous metamorphic events in the western metamorphic belt of the Coast Mountains complex near Petersburg, southeastern Alaska

USGS Publications Warehouse

Himmelberg, Glen R.; Brew, David A.

2005-01-01

The western metamorphic belt is part of the Coast Mountains Complex of southeastern Alaska and western Canada. This complex formed as a result of mid-Cretaceous through middle Eocene crustal shortening between the previously amalgamated Wrangellia and Alexander terranes (Insular superterrane) and previously accreted terranes of the North American continental margin (Intermontane superterrane). The western metamorphic belt, which ranges from a few kilometers to several tens of kilometers in width, records a complex sequence of contact-metamorphic and regional metamorphic events, the most significant of which are designated M1R, M2C-R, and M3R. The M1R regional metamorphic event ranged in grade from subgreenschist to greenschist facies and was overprinted by the M2C-R and M3R metamorphic events. The M2C-R metamorphic event is recorded in discrete contact-metamorphic aureoles and regional metamorphic-mineral assemblages related to tonalite-granodiorite plutons of the Admiralty-Revillagigedo plutonic belt. The M3R metamorphic belt, which is adjacent to the M2C-R belt, is characterized by regional Barrovian isograds of garnet, staurolite, kyanite, and sillimanite. Using the THERMOCALC program, pressure-temperature (P-T) conditions for the M2C-R metamorphic event are estimated to be in the ranges 5.3-7.5 kbars and 525-640 deg.C and for the M3R metamorphic event in the ranges 9.4-12.6 kbars and 730-895 deg.C. The M2C-R metamorphic event occurred at approximately 90 Ma, but the timing of the M3R metamorphic event is poorly documented and uncertain. On the basis of an 40Ar/39Ar age on actinolitic amphibole and a Sm-Nd age on garnet core, the timing of metamorphism might be constrained between 90+/-1 and 80+/-9 Ma, although the Sm-Nd age of 80+/-9 m.y. possibly reflects postpeak growth. Thermobarometric data suggest that the two events occurred at different crustal levels and followed different P-T paths. No evidence exists that M2C-R metamorphic-mineral assemblages were overprinted by the M3R metamorphic event, as proposed by some workers. Juxtaposition of the two belts of rocks probably occurred along the Coast shear zone during uplift and exhumation of the Coast Mountains.

Shared care versus hospital-based cardiac rehabilitation: a cost-utility analysis based on a randomised controlled trial

PubMed Central

Dehbarez, Nasrin Tayyari; Refsgaard, Jens; Kanstrup, Helle; Johnsen, Søren P; Qvist, Ina; Christensen, Bo; Søgaard, Rikke; Christensen, Kent L

2018-01-01

Background Changes in the organisation of chronic healthcare, an increased awareness of costs and challenges of low adherence in cardiac rehabilitation (CR) call for the exploration of more flexible CR programmes as alternatives to hospital-based CR (H-CR). A model of shared care cardiac rehabilitation (SC-CR) that included general practitioners and the municipality was developed. The aim of this study was to analyse the cost utility of SC-CR versus H-CR. Methods The cost-utility analysis was based on a randomised controlled trial of 212 patients who were allocated to SC-CR or H-CR and followed up for 12 months. A societal cost perspective was applied that included the cost of intervention, informal time, healthcare and productivity loss. Costing was based on a microcosting approach for the intervention and on national administrative registries for the other cost categories. Quality-adjusted life years (QALYs) were based on the EuroQol 5-Dimensions measurements at baseline, after 4 months and after 12 months. Conventional cost-effectiveness methodology was employed to estimate the net benefit of SC-CR. Results The average cost of SC-CR was 165.5 kDKK and H-CR 163 kDKK. Productivity loss comprised 74.1kDKK and 65.9 kDKK. SC-CR cost was an additional 2.5 kDKK (95% CI −38.1 to 43.1) ≈ (0.33; −5.1 to 5.8 k€) and a QALY gain of 0.02 (95% CI −0.03 to 0.06). The probability that SC-CR would be cost-effective was 59% for a threshold value of willingness to pay of 300 kDKK (k€40.3). Conclusion CR after shared care model and H-CR are comparable and similar in socioeconomic terms. Trial registration number NCT01522001; Results. PMID:29531754

Looking for Strange Quark Matter in Cosmic Rays.

NASA Astrophysics Data System (ADS)

Shaulov, S. B.; Bezshapov, S. P.

2013-06-01

Usually it is supposed that the definition of the CR mass composition in knee region is the key to problem of CR spectrum modification in this range. However tens of the experiments were done for the last half of century and have not decided this problem up to now. The possible causes of fiasco and arguments in favour of necessity to reformulate attack method are discussed, taking into account a new experimental data about fine structure of CR spectrum and EAS core investigations. The possible presence of the exotic processes in the area of a knee is discussed. If exotic component really exists in CR then impossible to formulate correctly more common problem of mass composition without solving this one. It is represented, that the problem of presence of an exotic component in CR should be solved easier than a CR composition problem. The observational basis is discussed. The hypothesis of strange quark matter in CR is suggested for the exotic component.

Genome-Wide Association Study on the Development of Cross-Reactive Neutralizing Antibodies in HIV-1 Infected Individuals

PubMed Central

Euler, Zelda; van Gils, Marit J.; Boeser-Nunnink, Brigitte D.; Schuitemaker, Hanneke; van Manen, Daniëlle

2013-01-01

Broadly neutralizing antibodies may protect against HIV-1 acquisition. In natural infection, only 10–30% of patients have cross-reactive neutralizing humoral immunity which may relate to viral and or host factors. To explore the role of host genetic markers in the formation of cross-reactive neutralizing activity (CrNA) in HIV-1 infected individuals, we performed a genome-wide association study (GWAS), in participants of the Amsterdam Cohort Studies with known CrNA in their sera. Single-nucleotide polymorphisms (SNPs) with the strongest P-values are located in the major histocompatibility complex (MHC) region, close to MICA (P = 7.68×10−7), HLA-B (P = 6.96×10−6) and in the coding region of HCP5 (P = 1.34×10−5). However, none of the signals reached genome-wide significance. Our findings underline the potential involvement of genes close or within the MHC region with the development of CrNA. PMID:23372753

Fine-scale mapping of a locus for severe bipolar mood disorder on chromosome 18p11.3 in the Costa Rican population

PubMed Central

McInnes, L. Alison; Service, Susan K.; Reus, Victor I.; Barnes, Glenn; Charlat, Olga; Jawahar, Satya; Lewitzky, Steve; Yang, Qing; Duong, Quyen; Spesny, Mitzi; Araya, Carmen; Araya, Xinia; Gallegos, Alvaro; Meza, Luis; Molina, Julio; Ramirez, Rolando; Mendez, Roxana; Silva, Sandra; Fournier, Eduardo; Batki, Steven L.; Mathews, Carol A.; Neylan, Thomas; Glatt, Charles E.; Escamilla, Michael A.; Luo, David; Gajiwala, Paresh; Song, Terry; Crook, Stephen; Nguyen, Jasmine B.; Roche, Erin; Meyer, Joanne M.; Leon, Pedro; Sandkuijl, Lodewijk A.; Freimer, Nelson B.; Chen, Hong

2001-01-01

We have searched for genes predisposing to bipolar disorder (BP) by studying individuals with the most extreme form of the affected phenotype, BP-I, ascertained from the genetically isolated population of the Central Valley of Costa Rica (CVCR). The results of a previous linkage analysis on two extended CVCR BP-I pedigrees, CR001 and CR004, and of linkage disequilibrium (LD) analyses of a CVCR population sample of BP-I patients implicated a candidate region on 18p11.3. We further investigated this region by creating a physical map and developing 4 new microsatellite and 26 single-nucleotide polymorphism markers for typing in the pedigree and population samples. We report the results of fine-scale association analyses in the population sample, as well as evaluation of haplotypes in pedigree CR001. Our results suggest a candidate region containing six genes but also highlight the complexities of LD mapping of common disorders. PMID:11572994

Doppler-Zeeman mapping of the magnetic CP star HD 215441

NASA Astrophysics Data System (ADS)

Khokhlova, V. L.; Vasilchenko, D. V.; Stepanov, V. V.; Tsymbal, V. V.

1997-07-01

The method of Vasilchenko et al. (1996) is used to obtain a Doppler-Zeeman map of the magnetic CP star HD 215441. The magnetic field is approximated by a magnetic dipole that is arbitrarily shifted from the star center. The solution of the inverse problem yields the dipole parameters and the maps of Si, Ti, Cr, and Fe abundance anomalies; the coordinates of local magnetic vectors on the star surface are computed. A comparison of the distribution of abundance anomalies and the magnetic-field configuration reveals that in the region where the magnetic-field lines are vertical (near the magnetic pole), Si, Ti and Cr are highly deficient, while the Fe enhancement is strongest. In the regions where the magnetic-field lines are horizontal (near the magnetic equator), Si, Ti and Cr show the greatest overabundance. In these regions, the Fe abundance is also slightly enhanced and exhibits, as it were, a secondary maximum. The factors that limit the accuracy of Doppler-Zeeman mapping are reviewed.

Dietary Supplementation with Pioglitazone Hydrochloride and Chromium Methionine Improves Growth Performance, Meat Quality, and Antioxidant Ability in Finishing Pigs.

PubMed

Jin, Cheng-Long; Wang, Qiang; Zhang, Zong-Ming; Xu, Yin-Long; Yan, Hui-Chao; Li, Hai-Chang; Gao, Chun-Qi; Wang, Xiu-Qi

2018-05-02

This work was designed to investigate the synergistic effects of pioglitazone hydrochloride (PGZ) and chromium methionine (CrMet) on meat quality, muscle fatty acid profile, and antioxidant ability of pigs. Pigs in four groups were fed a basic diet or basic diet supplemented with 15 mg/kg of PGZ, 200 μg/kg of CrMet, or 15 mg/kg of PGZ + 200 μg/kg of CrMet. In comparison to the control group, the average daily feed intake, feed/gain ratio, and serum high-density lipoprotein level decreased in the PGZ + CrMet group. Dietary PGZ + CrMet supplementation increased carcass dressing percentage, intramuscular fat, and marbling score. The percentages of C18:1ω-9c, C18:2ω-6c, C18:3ω-3, and polyunsaturated fatty acid (PUFA) in the longissimus thoracis muscle were increased in the PGZ + CrMet group. Greater superoxide dismutase and glutathione peroxidase activities were observed in the PGZ + CrMet group compared to the control group. Collectively, these findings suggested that feed with PGZ and CrMet improved the growth performance and meat quality, especially for PUFA proportions and antioxidant ability.

Dietary Supplementation with Chromium Picolinate Influences Serum Glucose and Immune Response of Brown-Egg Laying Hens.

PubMed

Zhang, Shumin; Sun, Xiaoming; Liao, Xiudong; Lu, Lin; Zhang, Liyang; Ma, Qiugang; Luo, Xugang

2018-01-29

To investigate the effect of chromium picolinate (CrPic) on egg production performance, egg quality, blood indices, and immune function of laying hens, 270 23-week-old Beijing Red brown-egg laying hens were randomly assigned to one of three treatments with six replicates of 15 birds per replicate for each treatment in a completely randomized design. Laying hens were fed a Cr-unsupplemented corn-soybean meal basal diet (control, containing 0.45 mg Cr/kg by analysis) or the basal diet supplemented with 0.4 or 0.6 mg Cr/kg from CrPic for 10 weeks. Laying hens fed diets supplemented with CrPic had a lower (P < 0.05) serum glucose (GLU) concentration and higher (P < 0.03) serum antibody titer against Newcastle disease than those fed the control diet at 33 weeks of age. However, supplemental CrPic had no effect (P > 0.05) on egg production and egg quality of brown-egg laying hens from 24 to 33 weeks of age. The results from this study indicated that supplemental CrPic decreased serum GLU and enhanced the immune function of brown-egg laying hens.

Recent progress in the study of protective rust-layer formation on weathering steel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yamashita, M.; Misawa, T.

Latest understanding of protective rust layer on weathering steel and its application for structural steels is discussed. Phase transformation of the weathering steel rust layer during long-time exposure brings {alpha}-(Fe{sub 1{minus}x},Cr{sub x})OOH, Cr-substituted goethite, as the final protective rust layer. It is said that the Cr content in the Cr-substituted goethite layer increases gradiently with reaching the rust-steel interface. This increase in the Cr content gives densely packed fine crystal structure end cation selective ability, which impedes the penetration of aggressive corrosives including anions such as Cl{sup {minus}} and SO{sub 4}{sup 2{minus}}. Quite recently, new surface-treatment technique employing Cr{sub 2}(SO{submore » 4}){sub 3}, was proposed, which provides a possibility for obtaining the protective rust layer in a relatively short period even in the severe environment such as coastal region.« less

Association Analysis of Polymorphisms in TOMM40, CR1, PVRL2, SORL1, PICALM, and 14q32.13 Regions in Colombian Alzheimer Disease Patients.

PubMed

Ortega-Rojas, Jenny; Morales, Luis; Guerrero, Esneyder; Arboleda-Bustos, Carlos E; Mejia, Adriana; Forero, Diego; Lopez, Luis; Pardo, Rodrigo; Arboleda, Gonzalo; Yunis, Juan; Arboleda, Humberto

2016-01-01

We evaluated the association of several single-nucleotide polymorphisms in different genes including APOE, TOMM40, CR1, PVRL2, SORL1, PICALM, and GWA_14q32.13 in a Colombian sample of Late-Onset Alzheimer disease (LOAD) patients. A case-control study was conducted in 362 individuals (181 LOADs and 181 controls) to determine the association of single-nucleotide polymorphisms in APOE (e2, e3, and e4), TOMM40 (rs2075650), CR1 (rs665640), PVRL2 (rs6859), SORL1 (rs11218304), PICALM (rs3851179), and GWA_14q32.13 (rs11622883) with LOAD in a sample from Colombia. We were able to confirm the previously reported association of the APOE4 allele with AD. In addition, we report a new significant association with rs2075650 of TOMM40 for LOAD in our sample. We did not detect any significant interaction between TOMM40 and APOE4 carriers (heterozygous or homozygous) for disease risk development. However, Kaplan-Meier survival analyses suggest that AD patients with TOMM40 allele rs2075650-G have an average age of disease onset of 6 years earlier compared with carriers of the A allele. In addition, the age of disease onset is earlier if APOE4/4 is present. Our findings suggest that rs2075650 of TOMM40 could be involved in earlier presentation of LOAD in the Colombian population.

Reduction of Cr (VI) into Cr (III) by organelles of Chlorella vulgaris in aqueous solution: An organelle-level attempt.

PubMed

Chen, Zunwei; Song, Shufang; Wen, Yuezhong

2016-12-01

The priority pollutant chromium (Cr) was ubiquitous and great efforts have been made to reduce Cr (VI) into less-toxic Cr (III) by alga for the convenient availability and low expense. However, the functional role of organelle inside the algal cell in Cr (VI) reduction was poorly understood. In this study, organelles in green algae Chlorella vulgaris were extracted and further decorated for Cr (VI) reduction tests. Results showed that the chloroplast exhibited not only adsorption ability of total Cr (21.18% comparing to control) but also reduction potential of Cr (VI) (almost 70% comparing to control), whose most suitable working concentration was at 17μg/mL. Furtherly, the isolated thylakoid membrane (ITM) showed better Cr (VI) reduction potential with the presence of sodium alginate (SA), even though the Hill reaction activity (HRA) was inhibited. As for photosystem II (PSII), the addition of mesoporous silica SBA-15 enhanced the reduction ability through improving the light-harvesting complex (LHC) II efficiency and electron transport rate. On the whole, the reduction ability order of the three kinds of materials based on chloroplast in C. vulgaris was PSII@SBA-15>Chloroplast>ITM@SA. The attempt made in this study to reduce the Cr (VI) with C. vulgaris organelles might not only offer basement to detect the potential action mechanism of Cr (VI) reduction by C. vulgaris but also provide a new sight for the scavenge of heavy metal with biological materials. Copyright © 2016 Elsevier B.V. All rights reserved.

Formation of Superhard Chromium Carbide Crystal Microrods in Ni-Cr-C Systems

NASA Astrophysics Data System (ADS)

Val'chuk, V. P.; Zmienko, D. S.; Kolesov, V. V.; Chernozatonskii, L. A.

2018-04-01

Ni-Cr-C materials with a high hardness determined by the presence of regions consisting of Cr3C2 microrods with a record microhardness reaching 3200 kg/mm2 have been obtained. Their self-organization in a powder consisting of Ni, Cr, and carbon microparticles with a high weight percentage occurs in the process of its sintering at a temperature of 1300°C and the subsequent sharp cooling of the resulting alloy. A model has been proposed for the process of formation of such crystal microrods whose characteristics have been determined by hardness measurement, electron microscopy, and microchemical and X-ray diffraction analyses.

Deep Drawing Behavior of CoCrFeMnNi High-Entropy Alloys

NASA Astrophysics Data System (ADS)

Bae, Jae Wung; Moon, Jongun; Jang, Min Ji; Ahn, Dong-Hyun; Joo, Soo-Hyun; Jung, Jaimyun; Yim, Dami; Kim, Hyoung Seop

2017-09-01

Herein, the deep drawability and deep drawing behavior of an equiatomic CoCrFeMnNi HEA and its microstructure and texture evolution are first studied for future applications. The CoCrFeMnNi HEA is successfully drawn to a limit drawing ratio (LDR) of 2.14, while the planar anisotropy of the drawn cup specimen is negligible. The moderate combination of strain hardening exponent and strain rate sensitivity and the formation of deformation twins in the edge region play important roles in successful deep drawing. In the meanwhile, the texture evolution of CoCrFeMnNi HEA has similarities with conventional fcc metals.

Method for depleting BWRs using optimal control rod patterns

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taner, M.S.; Levine, S.H.; Hsiao, M.Y.

1991-01-01

Control rod (CR) programming is an essential core management activity for boiling water reactors (BWRs). After establishing a core reload design for a BWR, CR programming is performed to develop a sequence of exposure-dependent CR patterns that assure the safe and effective depletion of the core through a reactor cycle. A time-variant target power distribution approach has been assumed in this study. The authors have developed OCTOPUS to implement a new two-step method for designing semioptimal CR programs for BWRs. The optimization procedure of OCTOPUS is based on the method of approximation programming and uses the SIMULATE-E code for nucleonicsmore » calculations.« less

Surface modification of CoCr alloy using varying concentrations of phosphoric and phosphonoacetic acids: albumin and fibrinogen adsorption, platelet adhesion, activation, and aggregation studies.

PubMed

Thiruppathi, Eagappanath; Larson, Mark K; Mani, Gopinath

2015-01-01

CoCr alloy is commonly used in various cardiovascular medical devices for its excellent physical and mechanical properties. However, the formation of blood clots on the alloy surfaces is a serious concern. This research is focused on the surface modification of CoCr alloy using varying concentrations (1, 25, 50, 75, and 100 mM) of phosphoric acid (PA) and phosphonoacetic acid (PAA) to generate various surfaces with different wettability, chemistry, and roughness. Then, the adsorption of blood plasma proteins such as albumin and fibrinogen and the adhesion, activation, and aggregation of platelets with the various surfaces generated were investigated. Contact angle analysis showed PA and PAA coatings on CoCr provided a gradient of hydrophilic surfaces. FTIR showed PA and PAA were covalently bound to CoCr surface and formed different bonding configurations depending on the concentrations of coating solutions used. AFM showed the formation of homogeneous PA and PAA coatings on CoCr. The single and dual protein adsorption studies showed that the amount of albumin and fibrinogen adsorbed on the alloy surfaces strongly depend on the type of PA and PAA coatings prepared by different concentrations of coating solutions. All PA coated CoCr showed reduced platelet adhesion and activation when compared to control CoCr. Also, 75 and 100 mM PA-CoCr showed reduced platelet aggregation. For PAA coated CoCr, no significant difference in platelet adhesion and activation was observed between PAA coated CoCr and control CoCr. Thus, this study demonstrated that CoCr can be surface modified using PA for potentially reducing the formation of blood clots and improving the blood compatibility of the alloy.

Removal of trivalent and hexavalent chromium by seaweed biosorbent

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kratochvil, D.; Volesky, B.; Pimentel, P.

1998-09-15

Protonated or Ca-form Sargassum seaweed biomass bound up to 40 mg/g of Cr(III) by ion exchange at pH 4. An ion-exchange model assuming that the only species taken up by the biomass was Cr(OH){sup 2+} successfully fitted the experimental biosorption data for Cr(III). The maximum uptake of Cr(VI) by protonated Sargassum biomass at pH 2 was explained by simultaneous anion exchange and Cr(VI) to Cr(III) reduction. At pH <2.0, the reduction of Cr(VI) to Cr(III) dominated the equilibrium behavior of the batch systems, which was explained by the dependence of the reduction potential of HCrO{sub 4}{sup {minus}} ions on themore » pH. At pH >2.0, the removal of Cr(VI) was linked to the depletion of protons in equilibrium batch systems via an anion-exchange reaction. The optimum pH for Cr(VI) removal by sorption lies in the region where the two mechanisms overlap, which for Sargassum biomass is in the vicinity of pH 2. The existence of the optimum pH for the removal of Cr(VI) may be explained by taking into account (a) the desorption of Cr(III) from biomass at low pH and (b) the effect of pH on the reduction potential of Cr(VI) in aqueous solutions. Seventy percent of Cr(VI) bound to the seaweed at pH 2 can be desorbed with 0.2 M H{sub 2}SO{sub 4} via reduction to Cr(III).« less

Brain magnetic resonance spectroscopy in obsessive-compulsive disorder: the importance of considering subclinical symptoms of anxiety and depression.

PubMed

Bédard, Marie-Josée; Chantal, Sophie

2011-04-30

Brain metabolite concentrations have recently been assessed in different cerebral regions presumably targeted in patients with obsessive-compulsive disorder (OCD) using magnetic resonance spectroscopy (MRS). However, results have been divergent. Possible confounding variables, such as the cerebral localisation of investigated regions and metabolites considered, as well as subclinical symptoms of anxiety and depression, could have affected these MRS profiles. The main goal of this study was to assess MRS metabolite differences between 13 individuals with OCD and 12 matched healthy controls in seven brain regions potentially involved in OCD. The secondary objective was to assess the relationships between levels of anxiety and depression and brain metabolite concentrations. No difference was found for N-acetylaspartate, glutamate-glutamine, myo-inositol (mI) and choline relative to creatine (Cr) concentration in either the left or right orbitofrontal area, left or right median temporal lobe, left or right thalamus or the anterior cingulate cortex. A significant negative correlation between the mI/Cr in the left orbitofrontal area and the severity of OCD symptomatology was observed while subclinical anxiety and depression were closely related to brain metabolite ratios. Thus, these subclinical symptoms, commonly associated with OCD, should be considered in assessing brain metabolite concentrations and may be central to the comprehension of this disorder. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Time-dependent reorganization of the brain components underlying memory retention in trace eyeblink conditioning.

PubMed

Takehara, Kaori; Kawahara, Shigenori; Kirino, Yutaka

2003-10-29

Many studies have confirmed the time-limited involvement of the hippocampus in mnemonic processes and suggested that there is reorganization of the responsible brain circuitry during memory consolidation. To clarify such reorganization, we chose trace classical eyeblink conditioning, in which hippocampal ablation produces temporally graded retrograde amnesia. Here, we extended the temporal characterization of retrograde amnesia to other regions that are involved in acquisition during this task: the medial prefrontal cortex (mPFC) and the cerebellum. At a various time interval after establishing the trace conditioned response (CR), rats received an aspiration of one of the three regions. After recovery, the animals were tested for their CR retention. When ablated 1 d after the learning, both the hippocampal lesion and the cerebellar lesion group of rats exhibited a severe impairment in retention of the CR, whereas the mPFC lesion group showed only a slight decline. With an increase in interval between the lesion and the learning, the effect of the hippocampal lesion diminished and that of the mPFC lesion increased. When ablated 4 weeks after the learning, the hippocampal lesion group exhibited as robust CRs as its corresponding control group. In contrast, the mPFC lesion and the cerebellar lesion groups failed to retain the CRs. These results indicate that the hippocampus and the cerebellum, but only marginally the mPFC, constitute a brain circuitry that mediates recently acquired memory. As time elapses, the circuitry is reorganized to use mainly the mPFC and the cerebellum, but not the hippocampus, for remotely acquired memory.

The mitochondrial genome of the Japanese skeleton shrimp Caprella mutica (Amphipoda: Caprellidea) reveals a unique gene order and shared apomorphic translocations with Gammaridea.

PubMed

Kilpert, Fabian; Podsiadlowski, Lars

2010-06-01

This study presents the complete mitochondrial (mt) genome of the amphipod Caprella mutica, an east-Asian species, which recently invaded the coastal regions of North America, Europe, and New Zealand. It is the first complete sequence of a member of the amphipod subclade Caprellidea. The mt genome has a total length of 15,427 bp and is organized in a circular double-strand molecule. All 37 mt genes are present, including the common set of 22 tRNAs. Particularly noticeable is the duplication of the control region (CR). The additional CR is located between nad6 and cob, and is almost identical to the original one. The most extensive changes in the gene order affect nad5 and a block consisting of trnH, nad4, nad4L, and trnP-all inserted near the original CR. The gene nad5 is also inverted. Furthermore, a comparison with the pancrustacean ground pattern reveals additional changes of individual tRNA genes. Some of these changes are also shared by Metacrangonyx longipes and Parhyale hawaiensis. These arrangements were found only in amphipods and might be considered as apomorphic by character states of Amphipoda. In all the three species, there is good evidence that trnG originated from a rare duplication/remolding event of the adjacent trnW gene. Nevertheless, each of the three available amphipod mitogenome sequences also bears unique rearrangements. C. mutica, however, shows the most extensive rearrangement in comparison with the pancrustacean ground pattern.

Molecular analysis of ciprofloxacin resistance mechanisms in Malaysian ESBL-producing Klebsiella pneumoniae isolates and development of mismatch amplification mutation assays (MAMA) for rapid detection of gyrA and parC mutations.

PubMed

Al-Marzooq, Farah; Mohd Yusof, Mohd Yasim; Tay, Sun Tee

2014-01-01

Ninety-three Malaysian extended-spectrum β-lactamase (ESBL)-producing Klebsiella pneumoniae isolates were investigated for ciprofloxacin resistance. Two mismatch amplification mutation (MAMA) assays were developed and used to facilitate rapid detection of gyrA and parC mutations. The isolates were also screened for plasmid-mediated quinolone resistance (PMQR) genes including aac(6')-Ib-cr, qepA, and qnr. Ciprofloxacin resistance (MICs 4- ≥ 32  μ g/mL) was noted in 34 (37%) isolates, of which 33 isolates had multiple mutations either in gyrA alone (n = 1) or in both gyrA and parC regions (n = 32). aac(6')-Ib-cr was the most common PMQR gene detected in this study (n = 61), followed by qnrB and qnrS (n = 55 and 1, resp.). Low-level ciprofloxacin resistance (MICs 1-2  μ g/mL) was noted in 40 (43%) isolates carrying qnrB accompanied by either aac(6')-Ib-cr (n = 34) or a single gyrA 83 mutation (n = 6). Ciprofloxacin resistance was significantly associated with the presence of multiple mutations in gyrA and parC regions. While the isolates harbouring gyrA and/or parC alteration were distributed into 11 PFGE clusters, no specific clusters were associated with isolates carrying PMQR genes. The high prevalence of ciprofloxacin resistance amongst the Malaysian ESBL-producing K. pneumoniae isolates suggests the need for more effective infection control measures to limit the spread of these resistant organisms in the hospital.

Caloric restriction increases ketone bodies metabolism and preserves blood flow in aging brain.

PubMed

Lin, Ai-Ling; Zhang, Wei; Gao, Xiaoli; Watts, Lora

2015-07-01

Caloric restriction (CR) has been shown to increase the life span and health span of a broad range of species. However, CR effects on in vivo brain functions are far from explored. In this study, we used multimetric neuroimaging methods to characterize the CR-induced changes of brain metabolic and vascular functions in aging rats. We found that old rats (24 months of age) with CR diet had reduced glucose uptake and lactate concentration, but increased ketone bodies level, compared with the age-matched and young (5 months of age) controls. The shifted metabolism was associated with preserved vascular function: old CR rats also had maintained cerebral blood flow relative to the age-matched controls. When investigating the metabolites in mitochondrial tricarboxylic acid cycle, we found that citrate and α-ketoglutarate were preserved in the old CR rats. We suggest that CR is neuroprotective; ketone bodies, cerebral blood flow, and α-ketoglutarate may play important roles in preserving brain physiology in aging. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Cardiorespiratory Fitness is Associated with Atrophy in Alzheimer’s and Aging Over Two Years

PubMed Central

Vidoni, Eric D.; Honea, Robyn A.; Billinger, Sandra A.; Swerdlow, Russel H.; Burns, Jeffrey M.

2011-01-01

We sought to describe change in cardiorespiratory (CR) fitness over 2 years in those with early–stage Alzheimer’s disease (AD) and nondemented aging and assess the relationship of CR fitness with cognitive decline, brain atrophy and dementia progression. Individuals with early-stage AD (n=37) and without dementia (n=53) attended clinical evaluations, cognitive and exercise tests, and MRI at baseline and 2 years later. CR fitness was lower in those with AD over the study period. Lower baseline CR fitness was associated with progression of dementia severity in AD. Declining CR fitness over 2 years was associated with brain atrophy in AD, especially in the parahippocampus. In nondemented participants, there was a trend for lower baseline fitness to be related to cognitive decline. Both lower baseline CR fitness and declining CR fitness over 2 years were associated with regional brain atrophy. We conclude that CR fitness is chronically reduced in those with AD. Further in those with AD, CR fitness is associated with progression of dementia severity and brain atrophy in AD, suggesting a link between progression of dementia severity and cardiorespiratory health. PMID:21531480

Luminescent properties of Cr-doped (GdX, Y1-X)3Al5O12 infra-red scintillator crystals

NASA Astrophysics Data System (ADS)

Suzuki, Akira; Kurosawa, Shunsuke; Yamaji, Akihiro; Shoji, Yasuhiro; Pejchal, Jan; Kamada, Kei; Yokota, Yuui; Yoshikawa, Akira

2014-10-01

Cr-doped (GdX Y1-X)3Al5O12 (X = 0, 0.25, 0.50) crystals prepared by the micro-pulling down method were investigated to develop a infra-red scintillator for implantable patient dosimeter in radiation therapy. In order to evaluate their optical and scintillation performance, the following properties were measured: (i) transmittance between ultra-violet and near-infra red region, (ii) photoluminescence spectra under Xe-lamp excitation, and (iii) X-ray excited radio-luminescence spectra. Cr:Y3Al5O12 and Cr:(Gd0.25 Y0.75)3Al5O12 crystals showed increased transmittance of 80%, while Cr:(Gd0.50 Y0.50)3Al5O12 had a lower transmittance of 40% due to its polycrystalline structure. In addition, all the Cr:(GdX Y1-X)3Al5O12 crystals showed sharp scintillation luminescence peaks ascribed to Cr3+ d-d transitions. Therefore, these results suggested that Cr:Y3Al5O12 and Cr:(Gd0.25 Y0.75)3Al5O12 crystals can be candidate materials for the dosimeter use.

Changes on aggregation in mine waste amended with biochar and marble mud

NASA Astrophysics Data System (ADS)

Ángeles Muñoz, María; Guzmán, Jose; Zornoza, Raúl; Moreno-Barriga, Fabián; Faz, Ángel; Lal, Rattan

2016-04-01

Mining activities have produced large amounts of wastes over centuries accumulated in tailing ponds in Southeast Spain. Applications of biochar may have a high potential for reclamation of degraded soils. Distribution, size and stability of aggregates are important indices of soil physical quality. However, research data on aggregation processes at amended mining tailings with biochar are scanty. Therefore, the aim of this study was to determine the effects of seven different treatments involving biochar and marble mud (MM) on the aggregation in mine waste (MW). Seven different treatments were tested after 90 days of incubation in the laboratory. These treatments were the mix of MW and: biochar from solid pig manure (PM), biochar from cotton crop residues (CR), biochar from municipal solid waste (MSW), marble mud (MM), PM+MM, CR+MM, MSW+MM and control without amendment. High sand percentages were identified in the MW. The biochars made from wastes (PM, CR, MSW) were obtained through pyrolysis of feedstocks. The water stability of soil aggregates was studied. The data on total aggregation were corrected for the primary particles considering the sandy texture of the MW. Moreover, partial aggregation was determined for each fraction and the mean weight diameter (MWD) of aggregates was computed. Soil bulk density and total porosity were also determined. No significant differences were observed in total aggregation and MWD among treatments including the control. For the size range of >4.75 mm, there were significant differences in aggregates > 4.75 mm between CR+MM in comparison with that for CT. There were also significant differences between MSW and PM+MM for the 1-0.425 mm fraction, and between CT and MM and CR for 0.425-0.162 mm aggregate size fractions. Therefore, CR-derived biochar applied with MM enhanced stability of macro-aggregates. Furthermore, soil bulk density was also the lowest bulk density and total porosity the highest for the CR-derived biochar treatment because macro aggregate stability is largely responsible for macro-porosity. The decrease in bulk density may be an indication of a positive effect for mine waste reclamation. Conversely, no differences were observed among treatments in micro-aggregate stability. Apparently, low organic matter contents in MW needed to be co-amended with labile organic amendments to effectively increase soil aggregation. Furthermore, the presence of Fe hydroxides could also increase the micro-aggregation. Additional research is needed to understand the mechanisms of mine soil reclamation. Acknowledgement : This work has been funded by Fundación Séneca (Agency of Science and Technology of the Region of Murcia, Spain

The free radical scavenger, edaravone, ameliorates delayed neuropsychological sequelae after acute carbon monoxide poisoning in rabbits.

PubMed

Qingsong, Wang; Yeming, Guan; Xuechun, Liu; Hongjuan, Liu; Jing, Wang

2013-01-01

The mechanism underlying delayed neuropsychological sequelae (DNS) after acute carbon monoxide (CO) poisoning is unclear. There are no effective treatments for DNS. As part of a new generation of antioxidants, edaravone has been reported to improve clinical outcomes in patients exhibiting ischemic strokes. There has been little data about edaravone in relationship to DNS prevention and treatment. We hypothesized that edaravone could ameliorate DNS: Here we test that hypothesis in rabbits Rabbits were randomly divided into sham control,DNS group, saline group and edaravone group. DNS model was made by intraperitoneal injection of CO. Normal saline or edaravone (1 mg/kg, twice daily, a total of one course for 14 days) was infused through the ear vein from Day 15 since the DNS model was established. Serum superoxide dismutase (SOD) activity and malondialdehyde (MDA) were measured in each group. Magnetic resonance spectroscopy (MRS) was used to examine regions of the brain for various compounds. The apoptotic index and neuronal density in the hippocampal CA1 area were also investigated. SOD activity decreased significantly and MDA content increased substantially in the DNS group and saline group when compared with the sham control (p < 0.01). Conversely, in the edaravone group, serum SOD activity significantly increased and MDA levels significantly decreased when compared with DNS and saline group (p < 0.01). In the DNS group, the spectra of H1-MRS showed an elevated Cho/Cr and Lac/Cr ratio, and a marked decrease in the NAA/Cr ratio (p < 0.01). Compared with the saline group and DNS group, the NAA/Cr ratio was significantly increased, and the Cho/Cr and Lac/Cr ratio were significantly decreased in the edaravone group (p < 0.01). The apoptotic index in the edaravone group was significantly lower than that of the DNS and saline groups (p < 0.01, respectively), while the neuronal density in edaravone group was significantly higher than that of the DNS and saline group in the hippocampal CA1 area (p < 0.01, respectively). Our present research demonstrates that edaravone could ameliorate DNS after acute carbon monoxide poisoning in rabbits. These results suggest free radicals could be involved in the underlying mechanisms of DNS. Furthermore, brain MRS shows promise as a tool for early diagnosis for DNS.

Urinary Uric Acid/Creatinine Ratio - A Marker For Perinatal Asphyxia

PubMed Central

Patel, Kinjal Prahaladbhai; Makadia, Mayur Goradhanbhai; Patel, Vishwal Indravardan; Nilayangode, Haridas Neelakandan

2017-01-01

Background Perinatal hypoxia is one of the leading causes of perinatal mortality in developing countries. Both apgar score and arterial blood pH predict the neonatal mortality in asphyxia. Apgar score alone does not predict neurologic outcome and as it is influenced by various factors. This study was conducted to evaluate the utility and sensitivity of urinary uric acid to creatinine ratio (UA/Cr ratio) in asphyxia diagnosis, compared to invasive Arterial Blood Gas (ABG) analysis. Aim To assess the urinary uric acid/creatinine ratio as an additional marker for perinatal asphyxia compared with ABG analysis in apgar score monitoring. Materials and Methods The present case control study was conducted at a teaching hospital in Central Gujarat. Data of 40 healthy newborns and 40 asphyxiated newborns were collected. In absence of regional estimates, a sample of size 39 was required to attain a power of 80% at 5% alpha (type I error) considering a moderate effect size of 0.65. (UA/Cr) ratio was measured from the spot urine sample collected during 24-72 hours of birth. Statistical analysis was performed by Independent t-test, Pearson’s correlation coefficient (r) and Receiver Operating Characteristic (ROC) plots. Results The mean (UA/Cr ratio) (2.75±0.18 vs 1.78±0.23) is significantly higher in asphyxiated group than in the control group (p<0.0001). Urinary UA/Cr ratio had negative correlation with blood pH (r= -0.27, p=0.18), which was not significant (p>0.05). Urinary UA/Cr ratio with criterion of >2.3 had 100% sensitivity, 100% specificity with AUC of 1 (p<0.0001) had a better predictive value. Conclusions Apgar score is usually reduced in neonates with congenital anomalies and premature neonates. Hence, it is preferable that the clinical diagnosis of asphyxia by apgar scores be supported by other investigations so that early decision can be taken about the level of care the baby needs. pH, lactates and base deficits change with establishment of respiration following resuscitation. However, pH, lactate, base deficit estimations are invasive and need rapid estimations. Non-invasive urinary UA/Cr ratio may be an answer to these issues as it easy, economical and equally efficient. PMID:28274014

[Clinical application of proton magnetic resonance spectroscopy in children with idiopathic epilepsy].

PubMed

Shao, Xiao-Li; Zhou, Zhong-Shu; Hong, Wen

2010-06-01

This study examined the biochemical metabolism by proton magnetic resonance spectroscopy ('H-MRS) in order to explore the value of 'H-MRS in idiopathic epilepsy in children. Thirty-three children with idiopathic epilepsy (14 cases with history of febrile seizures and 19 cases without) and six normal controls experienced MRI of the skull and brain and single-voxel 'H-MRS examinations of the hippocampi-temporal lobe. The signal intensities of N-acetylaspartate (NAA), eatine+phosphocreatine (Cr), choline-containing compounds (Cho) and lactate (Lac) and the ratios of NAA/ (Cho+Cr) and Lac/Cr were compared between the patients and normal controls. MRI examination showed that only one child with epilepsy had myelin dysplasia. 'H-MRS examination showed that the ratio of NAA/ (Cho+Cr) in the epilepsy group was lower than that in the control group (0.64+/-0.07 vs 0.73+/-0.05; P<0.01). The epileptic children with history of febrile seizures had a more decreased ratio of NAA/ (Cho+Cr) compared with those without the history (0.61+/-0.07 vs 0.66+/-0.06; P<0.05). There were no significant differences in the ratio of Lac/Cr between the epilepsy and the control groups. 'H-MRS may provide early information on brain injury sensitively and non-invasively in children with epilepsy. It may be used for diagnosis and prognosis evaluation of epilepsy.

Determination of Cd, Cr, Pb and Ni contents among Parkinson's disease individuals: a case-control study.

PubMed

Gupta, Vineeta; Ansari, Nasreen Ghazi; Garg, Ravindra Kumar; Khattri, Sanjay

2017-09-01

Various uses of metals in industries, including the domestic sphere, agriculture, medicine and technology, have led to their wide distribution in the environment. These result in raising concerns over their potential effects on human health and the environment. Because of their high degree of toxicity, Cd, Cr and Pb are some of the priority metals that are of public health significance. The levels of Cd, Cr, Pb and Ni were measured in Parkinson's disease (PD) patients. Blood samples were collected from 40 patients and 40 healthy controls, and stored at -80 °C until assayed. Atomic absorption spectrophotometry was used to determine the levels of metals. The level of Pb was significantly decreased in patients than in controls. However, the difference in the level of Ni between patients and controls failed to reach significance. Cr was not detectable in patients, but it was measurable in 12 controls (controls = 0.056-2.397 µg/ml). Similarly, Cd was not detectable in patients, but it was measurable in all the controls (controls = 0.004-1.268 µg/ml). Pb was the only metal that was found in all study participants (PD = 0.012-2.758 µg/ml and controls = 0.779-9.840 µg/ml). Ni could be measured only in six patients and in all the controls (PD = 0.154-0.754 µg/ml and controls = 0.034-1.691 µg/ml). Patients exhibited significantly decreased levels of Pb than in controls. However, Cd, Cr and Ni were too low to be measured among the patients. This indicates that these metals might play a probable role in PD.

Isopropanolic black cohosh extract and recurrence-free survival after breast cancer.

PubMed

Henneicke-von Zepelin, H H; Meden, H; Kostev, K; Schröder-Bernhardi, D; Stammwitz, U; Becher, H

2007-03-01

To investigate the influence of an isopropanolic Cimicifuga racemosa extract (iCR) on recurrence-free survival after breast cancer, including estrogen-dependent tumors. This pharmacoepidemiologic observational retrospective cohort study examined breast cancer patients treated at general, gynecological and internal facilities linked to a medical database in Germany. The main endpoint was disease-free survival following a diagnosis of breast cancer. The impact of treatment with iCR following diagnosis was analyzed by Cox-proportional hazards models, controlling for age and other confounders. Of 18,861 patients, a total of 1,102 had received an iCR therapy. The mean overall observation time was 3.6 years. Results showed that iCR was not associated with an increase in the risk of recurrence but associated with prolonged disease-free survival. After 2 years following initial diagnosis, 14% of the control group had developed a recurrence, while the iCR group reached this proportion after 6.5 years. The primary Cox regression model controlling for age, tamoxifen use and other confounders demonstrated a protractive effect of iCR on the rate of recurrence (hazard ratio 0.83, 95% confidence interval 0.69 0.99). This effect remained consistent throughout all variations of the statistical model, including subgroup analyses. TNM status was unknown but did not bias the iCR treatment decision as investigated separately. Hence, it was assumed to be equally distributed between treatment groups. Correlation analyses showed good internal and external validity of the database. An increase in the risk of breast cancer recurrence for women having had iCR treatment, compared to women not treated with iCR is unlikely.

Facile controlled synthesis of micro/nanostructure MCrO 4 (M = Ba, Pb) by using Gemini surfactant C 12-PEG-C 12 as a soft template

NASA Astrophysics Data System (ADS)

Chang, Wengui; Shen, Yuhua; Xie, Anjian; Liu, Xue

2010-04-01

Gemini surfactants, double sodium α-sulfonic polyethylene glycol laurate (abbreviated C 12-PEG-C 12), were prepared and applied as soft templates in the controlled synthesis of BaCrO 4 and PbCrO 4 micro/nanocrystals. The template effects were investigated by adjusting the length of the spacer, using PEG400 and PEG4000, of the Gemini surfactant. The results indicated that the size and morphology of BaCrO 4 and PbCrO 4 micro/nanocrystals varied with the change in spacer length of C 12-PEG-C 12, suggesting that the different lengths of the polyethylene glycol group spacers in the Gemini surfactants played a key role in determining the size and shape of the MCrO 4 micro/nanoparticles. The dynamic process of the formation of the novel morphology BaCrO 4 crystals showed that the morphology grew from a round-bar polyhedron, to regular polyhedron, to approximate octahedron to a uniform pistachio nut shape. The growth mechanism of the BaCrO 4 micro/nanocrystals was explained that C 12-PEG-C 12 had a greater interfacial adsorption and would effectively control the shape evolution during the crystal growth, while PbCrO 4 could be explained that the Gemini surfactants can undergo liquid-crystalline phase transitions with long channels providing a soft template effect and derived the nanorods formation. Room temperature fluorescence spectra were studied and these showed that the pistachio-shaped BaCrO 4 microcrystals and PbCrO 4 nanorods possess photoactive luminescence properties with emission peaks at 470 and 549 nm, respectively.

Enrichment and exposure assessment of As, Cr and Pb of the soils in the vicinity of Stawell, Victoria, Australia.

PubMed

Noble, Ryan R P; Hough, Robert M; Watkins, Ronald T

2010-06-01

Stawell Gold Mine in NW Victoria, Australia, mines ores that contain large concentrations of As and significant quantities of the metals Pb and Cr. The aim of this research was to understand the dispersion, enrichment and probable exposure of these potentially hazardous elements around the mine site. Fifty-five surface soil samples were collected near the mine (<15 km) and analysed by ICP-MS/OES following bioavailable and four-acid extractions. Soils near the mine show greater concentrations of As, Cr and Pb than those near a regionally determined background. This is attributed to the combination of a natural geochemical halo around mineralization and anthropogenic dispersion due to mining and urbanization. Total As concentrations were between 16 and 946 mg kg(-1) near the mine in a regional background of 1-16 mg kg(-1). Total Cr concentrations were between 18 and 740 mg kg(-1) near the mine in a regional background of 26-143 mg kg(-1). Total Pb concentrations were between 12 and 430 mg kg(-1) near the mine in a regional background of 9-23 mg kg(-1). Dispersion of contaminant elements from the present ore processing is <500 m. The most enriched soils occur close to the town and are unrelated to present mining practices. The bioavailable As, Cr and Pb, soil ingestion rates and Risk Reference Doses were used to estimate health risks. An average toddler (12 kg) would need to consume at least 1.5 g, and most likely 12 g, of soil per day to show some symptoms of As toxicity. The maximum measured bioavailable As would pose a risk at average ingestion rates of 200 mg per day. Individuals with soil-eating disorders would exceed the safe daily consumption limits for As, and potentially Cr and Pb. Small children are not typically exposed to soil everyday, very few have soil eating disorders, and, therefore, the health risk from the soils around the mine is minimal.

Effect of Nozzle Geometry on the Microstructure and Properties of HVAF-Sprayed WC-10Co4Cr and Cr3C2-25NiCr Coatings

NASA Astrophysics Data System (ADS)

Matikainen, V.; Koivuluoto, H.; Vuoristo, P.; Schubert, J.; Houdková, Š.

2018-04-01

Thermally sprayed hard metal coatings are the industrial standard solution for numerous demanding applications to improve wear resistance. In the aim of improving coating quality by utilising finer particle size distributions, several approaches have been studied to control the spray temperature. The most viable solution is to use the modern high velocity air-fuel (HVAF) spray process, which has already proven to produce high-quality coatings with dense structures. In HVAF spray process, the particle heating and acceleration can be efficiently controlled by changing the nozzle geometry. In this study, fine WC-10Co4Cr and Cr3C2-25NiCr powders were sprayed with three nozzle geometries to investigate their effect on the particle temperature, velocity and coating microstructure. The study demonstrates that the particle melting and resulting carbide dissolution can be efficiently controlled by changing the nozzle geometry from cylindrical to convergent-divergent. Moreover, the average particle velocity was increased from 780 to over 900 m/s. The increase in particle velocity significantly improved the coating structure and density. Further evaluation was carried out to resolve the effect of particle in-flight parameters on coating structure and cavitation erosion resistance, which was significantly improved in the case of WC-10Co4Cr coatings with the increasing average particle velocity.

Role of liver fatty acid binding protein in hepatocellular injury: effect of CrPic treatment.

PubMed

Fan, Weijiang; Chen, Kun; Zheng, Guoqiang; Wang, Wenhang; Teng, Anguo; Liu, Anjun; Ming, Dongfeng; Yan, Peng

2013-07-01

This study was designed to investigate the molecular mechanisms of chromium picolinate (CrPic, Fig. 1) hepatoprotective activity from alloxan-induced hepatic injury. Diabetes is induced by alloxan-treatment concurrently with the hepatic injury in mice. In this study, we investigate the protective effect of CrPic treatment in hepatic injury and the signal role of liver fatty acid binding protein in early hepatocellular injury diagnostics. In this study, alanine aminotransferase (ALT; EC 2.6.1.2) and aspartate aminotransferase (AST; EC 2.6.1.1) levels in the alloxan group were higher 71% and 50%, respectively, than those of the control group (ALT: 14.51±0.74; AST: 22.60±0.69). The AST and ALT levels in CrPic group were of minimal difference compared to the control groups. Here, CrPic exhibited amelioration alloxan induced oxidative stress in mouse livers. A significant increase in liver fatty acid-binding protein (L-FABP) was observed, which indicates increased fatty acid utilization in liver tissue [1]. In this study, the mRNA levels of L-FABP increased in both the control (1.1 fold) and CrPic (0.78 fold) groups compared the alloxan group. These findings suggest that hepatic injury may be prevented by CrPic, and is a potential target for use in the treatment of early hepatic injury. Copyright © 2013 Elsevier Inc. All rights reserved.

Automatic removal of cosmic ray signatures in Deep Impact images

NASA Astrophysics Data System (ADS)

Ipatov, S. I.; A'Hearn, M. F.; Klaasen, K. P.

The results of recognition of cosmic ray (CR) signatures on single images made during the Deep Impact mission were analyzed for several codes written by several authors. For automatic removal of CR signatures on many images, we suggest using the code imgclean ( http://pdssbn.astro.umd.edu/volume/didoc_0001/document/calibration_software/dical_v5/) written by E. Deutsch as other codes considered do not work properly automatically with a large number of images and do not run to completion for some images; however, other codes can be better for analysis of certain specific images. Sometimes imgclean detects false CR signatures near the edge of a comet nucleus, and it often does not recognize all pixels of long CR signatures. Our code rmcr is the only code among those considered that allows one to work with raw images. For most visual images made during low solar activity at exposure time t > 4 s, the number of clusters of bright pixels on an image per second per sq. cm of CCD was about 2-4, both for dark and normal sky images. At high solar activity, it sometimes exceeded 10. The ratio of the number of CR signatures consisting of n pixels obtained at high solar activity to that at low solar activity was greater for greater n. The number of clusters detected as CR signatures on a single infrared image is by at least a factor of several greater than the actual number of CR signatures; the number of clusters based on analysis of two successive dark infrared frames is in agreement with an expected number of CR signatures. Some glitches of false CR signatures include bright pixels repeatedly present on different infrared images. Our interactive code imr allows a user to choose the regions on a considered image where glitches detected by imgclean as CR signatures are ignored. In other regions chosen by the user, the brightness of some pixels is replaced by the local median brightness if the brightness of these pixels is greater by some factor than the median brightness. The interactive code allows one to delete long CR signatures and prevents removal of false CR signatures near the edge of the nucleus of the comet. The interactive code can be applied to editing any digital images. Results obtained can be used for other missions to comets.

Spatial variability and changes of metabolite concentrations in the cortico-spinal tract in multiple sclerosis using coronal CSI

PubMed Central

Tur, Carmen; Wheeler-Kingshott, Claudia AM; Altmann, Daniel R; Miller, David H; Thompson, Alan J; Ciccarelli, Olga

2014-01-01

We characterized metabolic changes along the cortico-spinal tract (CST) in multiple sclerosis (MS) patients using a novel application of chemical shift imaging (CSI) and considering the spatial variation of metabolite levels. Thirteen relapsing-remitting (RR) and 13 primary-progressive (PP) MS patients and 16 controls underwent 1H-MR CSI, which was applied to coronal-oblique scans to sample the entire CST. The concentrations of the main metabolites, i.e., N-acetyl-aspartate, myo-Inositol (Ins), choline containing compounds (Cho) and creatine and phosphocreatine (Cr), were calculated within voxels placed in regions where the CST is located, from cerebral peduncle to corona radiata. Differences in metabolite concentrations between groups and associations between metabolite concentrations and disability were investigated, allowing for the spatial variability of metabolite concentrations in the statistical model. RRMS patients showed higher CST Cho concentration than controls, and higher CST Ins concentration than PPMS, suggesting greater inflammation and glial proliferation in the RR than in the PP course. In RRMS, a significant, albeit modest, association between greater Ins concentration and greater disability suggested that gliosis may be relevant to disability. In PPMS, lower CST Cho and Cr concentrations correlated with greater disability, suggesting that in the progressive stage of the disease, inflammation declines and energy metabolism reduces. Attention to the spatial variation of metabolite concentrations made it possible to detect in patients a greater increase in Cr concentration towards the superior voxels as compared to controls and a stronger association between Cho and disability, suggesting that this step improves our ability to identify clinically relevant metabolic changes. PMID:23281189

Coptidis Rhizoma Prevents Heat Stress-Induced Brain Damage and Cognitive Impairment in Mice

PubMed Central

Moon, Minho; Huh, Eugene; Song, Eun Ji; Hwang, Deok-Sang; Lee, Tae Hee; Oh, Myung Sook

2017-01-01

Heat stress conditions lead to neuroinflammation, neuronal death, and memory loss in animals. Coptidis Rhizoma (CR) exhibits potent fever-reducing effects and has been used as an important traditional medicinal herb for treating fever. However, to date, the effects of antipyretic CR on heat-induced brain damages have not been investigated. In this study, CR significantly reduced the elevation of ear and rectal temperatures after exposure to heat in mice. Additionally, CR attenuated hyperthermia-induced stress responses, such as release of cortisol into the blood, and upregulation of heat shock protein and c-Fos in the hypothalamus and hippocampus of mice. The administration of CR inhibited gliosis and neuronal loss induced by thermal stress in the hippocampal CA3 region. Treatment with CR also reduced the heat stress-induced expression of nuclear factor kappa β, tumor necrosis factor-α, and interleukin-1β (IL-1β) in the hippocampus. Moreover, CR significantly decreased proinflammatory mediators such as IL-9 and IL-13 in the heat-stressed hypothalamus. Furthermore, CR attenuated cognitive dysfunction triggered by thermal stress. These results indicate that CR protects the brain against heat stress-mediated brain damage via amelioration of hyperthermia and neuroinflammation in mice, suggesting that fever-reducing CR can attenuate thermal stress-induced neuropathology. PMID:28946610

Tuning the onset of ferromagnetism in heterogeneous bimetallic nanoparticles by gas phase doping

NASA Astrophysics Data System (ADS)

Bohra, Murtaza; Grammatikopoulos, Panagiotis; Singh, Vidyadhar; Zhao, Junlei; Toulkeridou, Evropi; Steinhauer, Stephan; Kioseoglou, Joseph; Bobo, Jean-François; Nordlund, Kai; Djurabekova, Flyura; Sowwan, Mukhles

2017-11-01

In the nanoregime, chemical species can reorganize in ways not predicted by their equilibrium bulk behavior. Here, we engineer Ni-Cr nanoalloys at the magnetic end of their compositional range (i.e., 0-15 at. % Cr), and we investigate the effect of Cr incorporation on their structural stability and resultant magnetic ordering. To ensure their stoichiometric compositions, the nanoalloys are grown by cluster beam deposition, a method that allows one-step, chemical-free fabrication of bimetallic nanoparticles. While full Cr segregation toward nanoparticle surfaces is thermodynamically expected for low Cr concentrations, metastability occurs as the Cr dopant level increases in the form of residual Cr in the core region, yielding desirable magnetic properties in a compensatory manner. Using nudged elastic band calculations, residual Cr in the core is explained based on modifications in the local environment of individual Cr atoms. The resultant competition between ferromagnetic and antiferromagnetic ordering gives rise to a wide assortment of interesting phenomena, such as a cluster-glass ground state at very low temperatures and an increase in Curie temperature values. We emphasize the importance of obtaining the commonly elusive magnetic nanophase diagram for M -Cr (M =Fe , Co, and Ni) nanoalloys, and we propose an efficient single-parameter method of tuning the Curie temperature for various technological applications.

Localization of new, microdissection- generated, anonymous markers and of the genes Pcsk1, Dhfr, Ndub13, and Ccnb1 to rat chromosome region 2q1.

PubMed

Quan, X; Laes, J F; Ravoet, M; Van Vooren, P; Szpirer, J; Szpirer, C

2000-01-01

The centromeric region of rat chromosome 2 (2q1) harbors unidentified quantitative trait loci of genes that control tumor growth or development. To improve the mapping of this chromosome region, we microdissected it and generated 10 new microsatellite markers, which we included in the linkage map and/or radiation hybrid map of 2q1, together with other known markers, including four genes: Pcsk1 (protein convertase 1), Dhfr (dihydrofolate reductase), Ndub13 (NADH ubiquinone oxidoreductase subunit b13), and Ccnb1 (cyclin B1). To generate anchor points between the different maps, the gene Ndub13 and the microsatellite markers D2Ulb25 and D2Mit1 were also localized cytogenetically. The radiation map generated in region 2q1 extends its centromeric end of about 150 cR. Copyright 2000 S. Karger AG, Basel

[Correlation analysis between interleukin 6 polymorphism and adolescent idiopathic scoliosis susceptibility and bracing effectiveness].

PubMed

Gao, Junsheng; Zhang, Lu; Liu, Zhiang; Yao, Shuaihui; Gao, Songming

2018-06-01

To analyze the correlation between the polymorphism on interleukin 6 (IL-6) gene promoter region-174 locus and adolescent idiopathic scoliosis (AIS), including the susceptibility, the bracing effectiveness, and the possible mechanism. The 182 AIS patients and 210 healthy controls who met the inclusion criteria between January 2013 and January 2016 were collected as research objects. The genotype of IL-6 gene promoter region-174 locus, the serum IL-6, the bone mineral density (BMD) of femoral neck and vertebrae (L 1-4 ), and the bone metabolism parameters, including bone alkaline phosphatase (BALP), bone gla protein (BGP), tartrate resistant acid phosphatase 5b (TRACP-5b), urine Ca, and urine Ca/Cr, were detected. All research objects were divided into the AIS group and the control group according to whether they had AIS, the GG, CG, CC groups according to their genotype, and progression-free group and progression group according to the therapeutic effectiveness of 1-year bracing treatment. Statistical analysis for the indexes were conducted respectively. There were significant differences in AIS history, BMD of femoral neck and lumbar vertebrae between the AIS group and control group ( P <0.05). According to the therapeutic effecitveness of 1-year bracing treatment, 182 AIS patients were divided into progression-free group in 110 cases and progression group in 72 cases. The results of single factor analysis showed that there were significant differences in the genotype and allele distribution of IL-6 gene promoter region-174 locus, BMD of femoral neck and lumbar vertebrae, IL-6, TRACP-5b, urine Ca, and urine Ca/Cr between the progression-free group and progression group ( P <0.05). The results of multivariable analysis showed that the BMD of lumbar vertebrae, TRACP-5b, and urine Ca were the influencing factors of bracing efficacy ( P< 0.05). According to the results of genotype detection, all research objects were divided into GG group in 264 cases, CG group in 104 cases, and CC group in 24 cases. The IL-6, TRACP-5b, urine Ca, and urine Ca/Cr of GG type carriers were higher and BMD of femoral neck and lumbar vertebrae were lower when compared with the CG and CC type carriers ( P <0.05). The BMD of lumbar vertebrae of CG type carriers was lower than that of CC type carriers ( P <0.05). The polymorphism of IL-6 genepromoter region-174 locus wasn't correlated with the AIS susceptibility, but it was correlated (not independently correlated) with the scoliosis progression under bracing treatment, and the risk for G-carried patients was higher. The mechanism may be that the polymorphism affected the IL-6 expression level and eventually affected the BMD of AIS patients through the bone metabolism.

Mechanisms of peripheral phylogeographic divergence in the indo-Pacific: lessons from the spiny lobster Panulirus homarus.

PubMed

Farhadi, Ahmad; Jeffs, Andrew G; Farahmand, Hamid; Rejiniemon, Thankappan Sarasam; Smith, Greg; Lavery, Shane D

2017-08-18

There is increasing recognition of the concordance between marine biogeographic and phylogeographic boundaries. However, it is still unclear how population-level divergence translates into species-level divergence, and what are the principal factors that first initiate that divergence, and then maintain reproductive isolation. This study examines the likely forces driving population and lineage divergences in the broadly-distributed Indo-Pacific spiny lobster Panulirus homarus, which has peripheral divergent lineages in the west and east. The study focuses particularly on the West Indian Ocean, which is emerging as a region of unexpected diversity. Mitochondrial control region (mtCR) and COI sequences as well as genotypes of 9 microsatellite loci were examined in 410 individuals from 17 locations grouped into 7 regions from South Africa in the west, and eastward across to Taiwan and the Marquesas Islands. Phylogenetic and population-level analyses were used to test the significance and timing of divergences and describe the genetic relationships among populations. Analyses of the mtCR revealed high levels of divergence among the seven regions (Ф ST  = 0.594, P < 0.001). Microsatellite analyses also revealed significant divergence among regions, but at a much lower level (F ST  = 0.066, P < 0.001). The results reveal different patterns of mtCR v. nDNA divergence between the two distinct peripheral lineages: a subspecies in South Africa and Madagascar, and a phylogeographically diverged population in the Marquesas. The results also expose a number of other more fine-scale population divergences, particularly in the Indian Ocean. The divergence of peripheral lineages in the west and east of the species' range appear to have been initiated and maintained by very different processes. The pattern of mitochondrial and nuclear divergence of the western lineage, implicates processes of parapatric isolation, secondary contact and introgression, and suggests possible maintenance through adaptation and behavioural reproductive isolation. In contrast, the eastern lineage appears to have diverged through a rare colonisation event, maintained through long-term isolation, and matches expectations of the core-periphery hypothesis. The process of active peripheral speciation may be a common force in the Indo-Pacific that helps drive some of the regions' recognized biogeographic boundaries.

Empirical constraints on partitioning of platinum group elements between Cr-spinel and primitive terrestrial magmas

NASA Astrophysics Data System (ADS)

Park, Jung-Woo; Kamenetsky, Vadim; Campbell, Ian; Park, Gyuseung; Hanski, Eero; Pushkarev, Evgeny

2017-11-01

Recent experimental studies and in situ LA-ICP-MS analysis on natural Cr-spinel have shown that Rh and IPGEs (Ir-group platinum group elements: Ru, Ir, Os) are enriched in the lattice of Cr-spinel. However, the factors controlling the partitioning behaviour of these elements are not well constrained. In this study, we report the Rh, IPGE, and trace element contents in primitive Cr-spinel, measured by LA-ICP-MS, from nine volcanic suites covering various tectonic settings including island arc picrites, boninites, large igneous province picrites and mid-ocean ridge basalts. The aim is to understand the factors controlling the enrichment of Rh and IPGEs in Cr-spinels, to estimate empirical partition coefficients between Cr-spinel and silicate melts, and to investigate the role of Cr-spinel fractional crystallization on the PGE geochemistry of primitive magmas during the early stages of fractional crystallization. There are systematic differences in trace elements, Rh and IPGEs in Cr-spinels from arc-related magmas (Arc Group Cr-spinel), intraplate magmas (Intraplate Group Cr-spinel), and mid-ocean ridge magmas (MORB Group Cr-spinel). Arc Group Cr-spinels are systematically enriched in Sc, Co and Mn and depleted in Ni compared to the MORB Group Cr-spinels. Intraplate Group Cr-spinels are distinguished from the Arc Group Cr-spinels by their high Ni contents. Both the Arc and Intraplate Group Cr-spinels have total Rh and IPGE contents of 22-689 ppb whereas the MORB Group Cr-spinels are depleted in Rh and IPGE (total < 20 ppb). Palladium and Pt contents are below detection limit for all of the studied Cr-spinels (<1-5 ppb). The time-resolved spectra of LA-ICP-MS data for Cr-spinels mostly show constant count rates for trace element and Rh and IPGEs, suggesting homogeneous distribution of these elements in Cr-spinels. The PGE spikes observed in several Cr-spinels were interpreted to be PGE-bearing mineral inclusions and excluded from calculating the PGE contents of the Cr-spinels. On primitive mantle normalized diagrams the Arc Group Cr-spinels are characterized by a fractionated pattern with high Rh and low Os. The Intraplate Group Cr-spinels show flat patterns with positive Ru anomalies. Our results, together with the experimental and empirical data from previous studies, show that PGE patterns of Cr-spinel largely mimic that of the rock in which they are found, and that Rh, Ir and Os contents increase with increasing Fe3+ contents (i.e. magnetite component) in Cr-spinel, although Ru does not. These observations suggest that the enrichment of Rh and IPGEs in Cr-spinel is controlled by a combination of the Rh and IPGE contents in parental melts and the magnetite component of the spinel. Empirical partition coefficients (D) for Rh and IPGEs between Cr-spinels and silicate melts were calculated using the Rh and IPGE contents of the Cr-spinel and their host volcanic rocks after subtracting the accumulation effect of Cr-spinel. The D values for the Intraplate and MORB Group Cr-spinels increase with increasing magnetite component in Cr-spinel and range from 6 to 512, which is consistent with previously reported experimental and empirical values. In contrast, the Arc Group Cr-spinels have significantly higher D values (e.g. up to ∼3700 for Ru) than those of the Intraplate and MORB Group at the same magnetite concentration in the Cr-spinel, suggesting Rh and IPGEs dissolved in silicate melt have stronger affinity for Cr spinel under arc magma conditions than in intraplate magmas. This may be partly attributed to the low temperature of arc magmas relative to intraplate magmas, which leads to the Arc Group Cr-spinels having more octahedral sites at the same magnetite components than the Intraplate Group Cr-spinels. Because of significantly higher D values for the Arc Group Cr-spinels, compared with the Intraplate Group and MORB Group spinels, fractional crystallization of Cr-spinel will more efficiently fractionate Rh and IPGE from Pd and Pt in arc systems than in intraplate and MORB systems, which accounts for the highly fractionated PGE patterns in arc basalts.

Phylogeography of the Koala, (Phascolarctos cinereus), and Harmonising Data to Inform Conservation

PubMed Central

Neaves, Linda E.; Frankham, Greta J.; Dennison, Siobhan; FitzGibbon, Sean; Flannagan, Cheyne; Gillett, Amber; Hynes, Emily; Handasyde, Kathrine; Helgen, Kristofer M.; Tsangaras, Kyriakos; Greenwood, Alex D.; Eldridge, Mark D. B.; Johnson, Rebecca N.

2016-01-01

The Australian continent exhibits complex biogeographic patterns but studies of the impacts of Pleistocene climatic oscillation on the mesic environments of the Southern Hemisphere are limited. The koala (Phascolarctos cinereus), one of Australia’s most iconic species, was historically widely distributed throughout much of eastern Australia but currently represents a complex conservation challenge. To better understand the challenges to koala genetic health, we assessed the phylogeographic history of the koala. Variation in the maternally inherited mitochondrial DNA (mtDNA) Control Region (CR) was examined in 662 koalas sampled throughout their distribution. In addition, koala CR haplotypes accessioned to Genbank were evaluated and consolidated. A total of 53 unique CR haplotypes have been isolated from koalas to date (including 15 haplotypes novel to this study). The relationships among koala CR haplotypes were indicative of a single Evolutionary Significant Unit and do not support the recognition of subspecies, but were separated into four weakly differentiated lineages which correspond to three geographic clusters: a central lineage, a southern lineage and two northern lineages co-occurring north of Brisbane. The three geographic clusters were separated by known Pleistocene biogeographic barriers: the Brisbane River Valley and Clarence River Valley, although there was evidence of mixing amongst clusters. While there is evidence for historical connectivity, current koala populations exhibit greater structure, suggesting habitat fragmentation may have restricted female-mediated gene flow. Since mtDNA data informs conservation planning, we provide a summary of existing CR haplotypes, standardise nomenclature and make recommendations for future studies to harmonise existing datasets. This holistic approach is critical to ensuring management is effective and small scale local population studies can be integrated into a wider species context. PMID:27588685

Temporal and spatial variation characteristics of atmospheric emissions of Cd, Cr, and Pb from coal in China

NASA Astrophysics Data System (ADS)

Tian, Hezhong; Cheng, Ke; Wang, Yan; Zhao, Dan; Lu, Long; Jia, Wenxiao; Hao, Jiming

2012-04-01

Multiple-year inventory of atmospheric emissions of cadmium (Cd), chromium (Cr), and lead (Pb) from coal burning in China have been established for the period 1980-2008 by using best available emission factors and annual activity data which are specified by different sub-categories of combustion facilities, coal types, and air pollution control devices. Our results show that the total emissions of Cd, Cr, and Pb have rapidly increased from 31.14 t, 1019.07 t, and 2671.73 t in 1980 to 261.52 t, 8593.35 t, and 12 561.77 t in 2008, respectively. The industrial sector ranks as the leading source, contributing ˜88.3%, ˜86.7%, and ˜81.8% of the total Cd, Cr, and Pb emissions, respectively. Remarkably uneven spatial allocation features are observed. The emissions are primarily concentrated in the provinces of the northern and eastern region of China owing to the dramatic difference in coal use by the industrial and power sectors. Monthly temporal emission profiles for different sectors are established by using indexes such as monthly thermal electricity generation, monthly gross industrial output values and monthly average ambient temperature. For the power plants, there are two peaks during cold and hot season while for the industrial sector, emissions are most substantial in the summer and autumn season. Further, uncertainties in the bottom-up inventories are quantified by Monte Carlo simulation, and the overall uncertainties are demonstrated as -16% to 45% for Cd, -13% to 20% for Cr, and -21% to 48% for Pb, respectively. To better understand the emissions of these metals and to adopt effective measures to prevent poisoning, more specific data collection and analysis are necessary.

Modified section method for laser-welding of ill-fitting cp Ti and Ni-Cr alloy one-piece cast implant-supported frameworks.

PubMed

Tiossi, R; Falcão-Filho, H; Aguiar Júnior, F A; Rodrigues, R C; Mattos, M da G; Ribeiro, R F

2010-05-01

This study aimed to verify the effect of modified section method and laser-welding on the accuracy of fit of ill-fitting commercially pure titanium (cp Ti) and Ni-Cr alloy one-piece cast frameworks. Two sets of similar implant-supported frameworks were constructed. Both groups of six 3-unit implant-supported fixed partial dentures were cast as one-piece [I: Ni-Cr (control) and II: cp Ti] and evaluated for passive fitting in an optical microscope with both screws tightened and with only one screw tightened. All frameworks were then sectioned in the diagonal axis at the pontic region (III: Ni-Cr and IV: cp Ti). Sectioned frameworks were positioned in the matrix (10-Ncm torque) and laser-welded. Passive fitting was evaluated for the second time. Data were submitted to anova and Tukey-Kramer honestly significant difference tests (P < 0.05). With both screws tightened, one-piece cp Ti group II showed significantly higher misfit values (27.57 +/- 5.06 microm) than other groups (I: 11.19 +/- 2.54 microm, III: 12.88 +/- 2.93 microm, IV: 13.77 +/- 1.51 microm) (P < 0.05). In the single-screw-tightened test, with readings on the opposite side to the tightened side, Ni-Cr cast as one-piece (I: 58.66 +/- 14.30 microm) was significantly different from cp Ti group after diagonal section (IV: 27.51 +/- 8.28 microm) (P < 0.05). On the tightened side, no significant differences were found between groups (P > 0.05). Results showed that diagonally sectioning ill-fitting cp Ti frameworks lowers misfit levels of prosthetic implant-supported frameworks and also improves passivity levels of the same frameworks when compared to one-piece cast structures.

Cardiac Sirt1 mediates the cardioprotective effect of caloric restriction by suppressing local complement system activation after ischemia-reperfusion.

PubMed

Yamamoto, Tsunehisa; Tamaki, Kayoko; Shirakawa, Kohsuke; Ito, Kentaro; Yan, Xiaoxiang; Katsumata, Yoshinori; Anzai, Atsushi; Matsuhashi, Tomohiro; Endo, Jin; Inaba, Takaaki; Tsubota, Kazuo; Sano, Motoaki; Fukuda, Keiichi; Shinmura, Ken

2016-04-15

Caloric restriction (CR) confers cardioprotection against ischemia-reperfusion (I/R) injury. We previously found the essential roles of endothelial nitric oxide synthase in the development of CR-induced cardioprotection and Sirt1 activation during CR (Shinmura K, Tamaki K, Ito K, Yan X, Yamamoto T, Katsumata Y, Matsuhashi T, Sano M, Fukuda K, Suematsu M, Ishii I. Indispensable role of endothelial nitric oxide synthase in caloric restriction-induced cardioprotection against ischemia-reperfusion injury.Am J Physiol Heart Circ Physiol 308: H894-H903, 2015). However, the exact mechanism by which Sirt1 in cardiomyocytes mediates the cardioprotective effect of CR remains undetermined. We subjected cardiomyocyte-specific Sirt1 knockout (CM-Sirt1(-/-)) mice and the corresponding control mice to either 3-mo ad libitum feeding or CR (-40%). Isolated perfused hearts were subjected to 25-min global ischemia, followed by 60-min reperfusion. The recovery of left ventricle function after I/R was improved, and total lactate dehydrogenase release into the perfusate during reperfusion was attenuated in the control mice treated with CR, but a similar cardioprotective effect of CR was not observed in the CM-Sirt1(-/-)mice. The expression levels of cardiac complement component 3 (C3) at baseline and the accumulation of C3 and its fragments in the ischemia-reperfused myocardium were attenuated by CR in the control mice, but not in the CM-Sirt1(-/-)mice. Resveratrol treatment also attenuated the expression levels of C3 protein in cultured neonatal rat ventricular cardiomyocytes. Moreover, the degree of myocardial I/R injury in conventional C3 knockout (C3(-/-)) mice treated with CR was similar to that in the ad libitum-fed C3(-/-)mice, although the expression levels of Sirt1 were enhanced by CR. These results demonstrate that cardiac Sirt1 plays an essential role in CR-induced cardioprotection against I/R injury by suppressing cardiac C3 expression. This is the first report suggesting that cardiac Sirt1 regulates the local complement system during CR. Copyright © 2016 the American Physiological Society.

HEART: heart exercise and remote technologies: a randomized controlled trial study protocol.

PubMed

Maddison, Ralph; Whittaker, Robyn; Stewart, Ralph; Kerr, Andrew; Jiang, Yannan; Kira, Geoffrey; Carter, Karen H; Pfaeffli, Leila

2011-05-31

Cardiovascular disease (CVD) is the leading cause of death worldwide. Cardiac rehabilitation (CR) is aimed at improving health behaviors to slow or reverse the progression of CVD disease. Exercise is a central element of CR. Technologies such as mobile phones and the Internet (mHealth) offer potential to overcome many of the psychological, physical, and geographical barriers that have been associated with lack of participation in exercise-based CR. We aim to trial the effectiveness of a mobile phone delivered exercise-based CR program to increase exercise capacity and functional outcomes compared with usual CR care in adults with CVD. This paper outlines the rationale and methods of the trial. A single-blinded parallel two-arm randomized controlled trial is being conducted. A total of 170 people will be randomized at 1:1 ratio either to receive a mHealth CR program or usual care. Participants are identified by CR nurses from two metropolitan hospitals in Auckland, New Zealand through outpatient clinics and existing databases. Consenting participants are contacted to attend a baseline assessment. The intervention consists of a theory-based, personalized, automated package of text and video message components via participants' mobile phones and the Internet to increase exercise behavior, delivered over six months. The control group will continue with usual CR. Data collection occurs at baseline and 24 weeks (post-intervention). The primary outcome is change in maximal oxygen uptake from baseline to 24 weeks. Secondary outcomes include post-intervention measures on self-reported physical activity (IPAQ), cardiovascular risk factors (systolic blood pressure, weight, and waist to hip ratio), health related quality of life (SF-36), and cost-effectiveness. This manuscript presents the protocol for a randomized controlled trial of a mHealth exercise-based CR program. Results of this trial will provide much needed information about physical and psychological well-being, and cost-effectiveness of an automated telecommunication intervention. If effective, this intervention has enormous potential to improve the delivery of CR and could easily be scaled up to be delivered nationally (and internationally) in a very short time, enhancing the translational aspect of this research. It also has potential to extend to comprehensive CR (nutrition advice, smoking cessation, medication adherence). ACTRN12611000117910.

Structure and Properties of Thermite Welds in Premium Rails

DOT National Transportation Integrated Search

1985-12-01

Thermite welds were used to join combinations of premium rails and AREA Controlled Cooled Carbon rails (i.e., standard rails). The premium rails comprised head-hardened rails and CrMo, CrV and Cr alloy rails. A major objective was to determine the fe...

Intestinal permeability to (/sup 51/Cr)EDTA in children with cystic fibrosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leclercq-Foucart, J.; Forget, P.; Sodoyez-Goffaux, F.

1986-05-01

Intestinal permeability was investigated in 14 children with cystic fibrosis making use of (/sup 51/Cr)EDTA as probe molecule. Ten normal young adults and 11 children served as controls. After oral administration of (/sup 51/Cr)EDTA, 24 h urine was collected. Urinary radioactivity was calculated and results expressed as percentage of oral dose excreted in 24 h urine. Mean and SEM were as follows: 2.51 +/- 0.21, 2.35 +/- 0.24, and 13.19 +/- 1.72 for control children, normal adults, and cystic fibrosis patients, respectively. The permeability differences between cystic fibrosis patients and either control children or control adults are significant (p lessmore » than 0.001).« less

Biased distributions and decay of long interspersed nuclear elements in the chicken genome.

PubMed

Abrusán, György; Krambeck, Hans-Jürgen; Junier, Thomas; Giordano, Joti; Warburton, Peter E

2008-01-01

The genomes of birds are much smaller than mammalian genomes, and transposable elements (TEs) make up only 10% of the chicken genome, compared with the 45% of the human genome. To study the mechanisms that constrain the copy numbers of TEs, and as a consequence the genome size of birds, we analyzed the distributions of LINEs (CR1's) and SINEs (MIRs) on the chicken autosomes and Z chromosome. We show that (1) CR1 repeats are longest on the Z chromosome and their length is negatively correlated with the local GC content; (2) the decay of CR1 elements is highly biased, and the 5'-ends of the insertions are lost much faster than their 3'-ends; (3) the GC distribution of CR1 repeats shows a bimodal pattern with repeats enriched in both AT-rich and GC-rich regions of the genome, but the CR1 families show large differences in their GC distribution; and (4) the few MIRs in the chicken are most abundant in regions with intermediate GC content. Our results indicate that the primary mechanism that removes repeats from the chicken genome is ectopic exchange and that the low abundance of repeats in avian genomes is likely to be the consequence of their high recombination rates.

Development of a Multiplex Single Base Extension Assay for Mitochondrial DNA Haplogroup Typing

PubMed Central

Nelson, Tahnee M.; Just, Rebecca S.; Loreille, Odile; Schanfield, Moses S.; Podini, Daniele

2007-01-01

Aim To provide a screening tool to reduce time and sample consumption when attempting mtDNA haplogroup typing. Methods A single base primer extension assay was developed to enable typing, in a single reaction, of twelve mtDNA haplogroup specific polymorphisms. For validation purposes a total of 147 samples were tested including 73 samples successfully haplogroup typed using mtDNA control region (CR) sequence data, 21 samples inconclusively haplogroup typed by CR data, 20 samples previously haplogroup typed using restriction fragment length polymorphism (RFLP) analysis, and 31 samples of known ancestral origin without previous haplogroup typing. Additionally, two highly degraded human bones embalmed and buried in the early 1950s were analyzed using the single nucleotide polymorphisms (SNP) multiplex. Results When the SNP multiplex was used to type the 96 previously CR sequenced specimens, an increase in haplogroup or macrohaplogroup assignment relative to conventional CR sequence analysis was observed. The single base extension assay was also successfully used to assign a haplogroup to decades-old, embalmed skeletal remains dating to World War II. Conclusion The SNP multiplex was successfully used to obtain haplogroup status of highly degraded human bones, and demonstrated the ability to eliminate possible contributors. The SNP multiplex provides a low-cost, high throughput method for typing of mtDNA haplogroups A, B, C, D, E, F, G, H, L1/L2, L3, M, and N that could be useful for screening purposes for human identification efforts and anthropological studies. PMID:17696300

Chromium fractionation and plant availability in tannery-sludge amended soil

NASA Astrophysics Data System (ADS)

Allué, Josep; Moya Garcés, Alba; Bech, Jaume; Barceló, Juan; Poschenrieder, Charlotte

2013-04-01

The leather industry represents an important economic sector in both developed and developing countries. Chromium tanning is the major process used to obtain high quality leather. Within the REACH regulation the use of Cr, especially CrVI, in the tanning process is under discussion in Europe. High Cr concentration in shoes and other Cr-tanned leather products can cause contact dermatitis in sensitive population. Moreover, the high Cr concentration is the major limiting factor for the use of tannery sludge as a source of organic matter in agricultural soils. Interest in Cr, however is not limited to its potential toxic effects. Chromium III is used as a dietary supplement because there are reports, but also controversy, about the positive effects of Cr III in glucose tolerance and type-2 diabetes. Adequate intake levels for Cr by the diet have been established between 25 and 35 µg/day for adult females and males, respectively. Sufficient supply of Cr III by the diet is preferable to the use of CrIII-salt based dietary supplements. The objective of the present work was to investigate whether Cr from tannery sludge-amended soil is available to Trigonella foenum-graecum plants, a plant used both as a spice and as a medicinal herb, because of its hypoglucemic effects. For this purpose clay loam soil (pH 7.8) was sieved (2mm) and thoroughly mixed with tannery sludge from a depuration station (Igualadina Depuració i Recuperació S.L., Igualada, Barcelona, Spain). The sludge had a Cr concentration of 6,034mg kg-1 and a 0.73 % of NH4-nitrogen. All the Cr was in the form of CrIII. Three treatments were disposed. Control soil receiving no sludge, a 60 mg kg-1 Cr treatment (10 g fresh sludge kg-1 soil) and a 120 mg kg-1 Cr treatment (20 g fresh sludge kg-1 soil). Control soil and the soil treated with 10g kg-1 sludge received NPK fertilizer in the form of ammonium sulfate, superfosfate, and KCl to rise the N,P, and K concentrations to similar levels to those achieved in the soils with the highest sludge dose (20 g kg-1). Soils from the different treatments were potted (5 L) and planted with Trigonella foenum graecum seeds (1 plant per pot). Plants were harvested in the vegetative stage and processed for tissue analysis of Cr, Fe, Zn and Pb. A sequential extraction procedure was applied to the soil for getting insight into the operationally defined soil fractions that incorporate the tannery sludge derived Cr. In any of the treatments Cr was detectable in the exchangeable and easily reducible fractions. In control soils around 10% of soil Cr was in the moderately reducible fraction and the rest in the residual fraction. Contrastingly tannery sludge amended soils incorporated most Cr in the moderately reducible fraction extracted by acid oxalate. This distribution in relation to plant Cr concentrations will be discussed. Acknowledgement: Supported by the Spanish Government (project BFU2010-14873)

Cardiac rehabilitation delivery model for low-resource settings

PubMed Central

Grace, Sherry L; Turk-Adawi, Karam I; Contractor, Aashish; Atrey, Alison; Campbell, Norm; Derman, Wayne; Melo Ghisi, Gabriela L; Oldridge, Neil; Sarkar, Bidyut K; Yeo, Tee Joo; Lopez-Jimenez, Francisco; Mendis, Shanthi; Oh, Paul; Hu, Dayi; Sarrafzadegan, Nizal

2016-01-01

Objective Cardiovascular disease is a global epidemic, which is largely preventable. Cardiac rehabilitation (CR) is demonstrated to be cost-effective and efficacious in high-income countries. CR could represent an important approach to mitigate the epidemic of cardiovascular disease in lower-resource settings. The purpose of this consensus statement was to review low-cost approaches to delivering the core components of CR, to propose a testable model of CR which could feasibly be delivered in middle-income countries. Methods A literature review regarding delivery of each core CR component, namely: (1) lifestyle risk factor management (ie, physical activity, diet, tobacco and mental health), (2) medical risk factor management (eg, lipid control, blood pressure control), (3) education for self-management and (4) return to work, in low-resource settings was undertaken. Recommendations were developed based on identified articles, using a modified GRADE approach where evidence in a low-resource setting was available, or consensus where evidence was not. Results Available data on cost of CR delivery in low-resource settings suggests it is not feasible to deliver CR in low-resource settings as is delivered in high-resource ones. Strategies which can be implemented to deliver all of the core CR components in low-resource settings were summarised in practice recommendations, and approaches to patient assessment proffered. It is suggested that CR be adapted by delivery by non-physician healthcare workers, in non-clinical settings. Conclusions Advocacy to achieve political commitment for broad delivery of adapted CR services in low-resource settings is needed. PMID:27181874

Effect of the self-monitoring approach on exercise maintenance during cardiac rehabilitation: a randomized, controlled trial.

PubMed

Izawa, Kazuhiro P; Watanabe, Satoshi; Omiya, Kazuto; Hirano, Yasuyuki; Oka, Koichiro; Osada, Naohiko; Iijima, Setsu

2005-05-01

To evaluate the effect of the self-monitoring approach (SMA) on self-efficacy for physical activity (SEPA), exercise maintenance, and objective physical activity level over a 6-mo period after a supervised 6-mo cardiac rehabilitation (CR) program. We conducted a randomized, controlled trial with 45 myocardial infarction patients (38 men, seven women; mean age, 64.2 yrs) recruited after completion of an acute-phase, exercise-based CR program. Patients were randomly assigned to an SMA group (n = 24) or control group (n = 21). Along with CR, the subjects in the SMA group self-monitored their weight and physical activity for 6 mos. The SMA used in this study was based on Bandura's self-efficacy theory and was designed to enhance confidence for exercise maintenance. The control group participated in CR only. All patients were evaluated with the SEPA assessment tool. Exercise maintenance, SEPA scores, and objective physical activity (average steps per week) as a caloric expenditure were assessed at baseline and during a 6-mo period after the supervised CR program. Mean period from myocardial infarction onset did not differ significantly between the SMA and control groups (12.1 +/- 1.3 vs. 12.2 +/- 1.2 mos, P = 0.692). All patients maintained their exercise routine in the SMA group. Mean SEPA score (90.5 vs. 72.7 points, P < 0.001) and mean objective physical activity (10,458.7 vs. 6922.5 steps/wk, P < 0.001) at 12 mos after myocardial infarction onset were significantly higher in the SMA than control group. SEPA showed significant positive correlation with objective physical activity (r = 0.642, P < 0.001). SMA during supervised CR may effectively increase exercise maintenance, SEPA, and objective physical activity at 12 mos after myocardial infarction onset.

Monitoring interferon β treatment response with magnetic resonance spectroscopy in relapsing remitting multiple sclerosis.

PubMed

Yetkin, Mehmet Fatih; Mirza, Meral; Dönmez, Halil

2016-09-01

The aim of this study is to compare the white matter of multiple sclerosis (MS) patients with healthy controls and to monitor the response to the treatment with magnetic resonance spectroscopy (MRS).Fifteen healthy controls and 36 recently diagnosed MS patients never treated with interferon β were included in this study. In the patient group, MRS was performed before treatment, at 6th and 12th month after the initiation of treatment and once in control group. Patient group was divided into 3 interferon groups randomly. Physical examination findings were recorded as Expanded Disability Status Scale scores before treatment, at 6th and 12th month of interferon treatment.At the end of 1 year follow up, 26 of 36 patients completed the study. In patients' white matter lesions, N-acetylaspartate/creatine (NAA/Cr) ratios were lower than control group's white matters. NAA/Cr ratios were higher in control group's white matter than patient's normal appearing white matter but this difference was not statistically significant. There was no difference in choline/creatine (Cho/Cr) ratios between 2 groups. In follow-up period, NAA/Cr and Cho/Cr ratios obtained from patients' white matter lesions and normal appearing white matter did not change statistically.This study showed that in MS patients' white matters, especially in white matter lesions, neuron viability is reduced compared with healthy controls' normal white matter; and in the patients treated with interferon β NAA/Cr ratios remained stable. These stable levels of metabolite ratios in the patients who received interferon β therapy can be explained with either the shortness of the follow-up period post-treatment or may reflect a positive effect of the beta interferon therapy on the progress of MS.

Effects of Cr methionine on glucose metabolism, plasma metabolites, meat lipid peroxidation, and tissue chromium in Mahabadi goat kids.

PubMed

Emami, A; Ganjkhanlou, M; Zali, A

2015-03-01

This study was designed to investigate the effects of chromium methionine (Cr-Met) on glucose metabolism, blood metabolites, meat lipid peroxidation, and tissue chromium (Cr) in Mahabadi goat kids. Thirty-two male kids (16.5 ± 2.8 kg BW, 4-5 months of age) were fed for 90 days in a completely randomized design with four treatments. Treatments were supplemented with 0 (control), 0.5, 1, and 1.5 mg Cr as Cr-Met/animal/daily. Blood samples were collected via heparin tubes from the jugular vein on 0, 21, 42, 63, and 90 days of experiment. On day 70, an intravenous glucose tolerance test (IVGTT) was conducted. At the end of the feeding trial, the kids were slaughtered, and the liver, kidney, and longissimus dorsi (LD) muscle samples were collected. Plasma glucose, insulin, and triglyceride concentrations were decreased by Cr supplementation (P < 0.05). LD muscle malondialdehyde (MDA) decreased, and plasma and tissue Cr contents increased with increasing supplemental Cr levels (P < 0.05). Plasma glucose concentrations at 30 and 60 min after glucose infusion were lower in the kids fed 1.5 mg Cr diet than the kids fed control diet (P < 0.05). The IVGTT indicated that the kids supplemented with 1.5 mg Cr had higher glucose clearance rate (K) and lower glucose half-life (T½; P < 0.05). Glucose area under the response curve (AUC) from 0 to 180 min after glucose infusion was decreased linearly (P < 0.01) by supplemental Cr. The results suggested that supplemental Cr may improve glucose utilization and lipid oxidation of meat in fattening kid.

EXTENDED ANALYSIS OF THE SPECTRUM OF SINGLY IONIZED CHROMIUM (Cr II)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sansonetti, Craig J.; Nave, Gillian

2014-08-01

We have made new observations of the spectrum of singly ionized chromium (Cr II) in the region 2850-37900 Å with the National Institute of Standards and Technology 2 m Fourier transform spectrometer. These data extend our previously reported observations in the near-ultra-violet region. We present a comprehensive list of more than 5300 Cr II lines classified as transitions among 456 even and 457 odd levels, 179 of which are newly located in this work. Using highly excited levels of the 3d {sup 4}({sup 5} D)5g, 3d {sup 4}({sup 5} D)6g, and 3d {sup 4}({sup 5}D)6h configurations, we derive an improvedmore » ionization energy of 132971.02 ± 0.12 cm{sup –1} (16.486305 ± 0.000015 eV)« less

Creatine supports propagation and promotes neuronal differentiation of inner ear progenitor cells.

PubMed

Di Santo, Stefano; Mina, Amir; Ducray, Angélique; Widmer, Hans R; Senn, Pascal

2014-05-07

Long-term propagation of inner ear-derived progenitor/stem cells beyond the third generation and differentiation into inner ear cell types has been shown to be feasible, but challenging. We investigated whether the known neuroprotective guanidine compound creatine (Cr) promotes propagation of inner ear progenitor/stem cells as mitogen-expanded neurosphere cultures judged from the formation of spheres over passages. In addition, we studied whether Cr alone or in combination with brain-derived neurotrophic factor (BDNF) promotes neuronal differentiation of inner ear progenitors. For this purpose, early postnatal rat spiral ganglia, utricle, and organ of Corti-derived progenitors were grown as floating spheres in the absence (controls) or presence of Cr (5 mM) from passage 3 onward. Similarly, dissociated sphere-derived cultures were differentiated for 14 days in the presence or absence of Cr (5 mM) and spiral ganglia sphere-derived cultures in a combination of Cr with the neurotrophin BDNF (50 ng/ml). We found that the cumulative total number of spheres over all passages was significantly higher after Cr supplementation as compared with controls in all the three inner ear cultures. In contrast, sphere sizes were not affected by the administration of Cr. Administration of Cr during differentiation of spiral ganglia cells resulted in a significantly higher density of β-III-tubulin-positive cells compared with controls, whereas densities of myosin VIIa-positive cells in cultures of utricle and organ of Corti were not affected by the treatment. Importantly, a combination of Cr with the neurotrophin BDNF resulted in further significantly increased densities of β-III-tubulin-positive cells in cultures of spiral ganglia cells as compared with single treatments. In sum, Cr promoted continuing propagation of rat inner ear-derived progenitor cells and supported specifically in combination with BDNF the differentiation of neuronal cell types from spiral ganglion-derived spheres.

Optimal multichannel transmission for improved cr-MREPT

NASA Astrophysics Data System (ADS)

Ariturk, Gokhan; Ziya Ider, Yusuf

2018-02-01

Magnetic resonance electrical properties tomography (MR-EPT), aiming at reconstructing the EP’s at radio frequencies, uses the H + field (both magnitude and phase) distribution within the object. One of the MR-EPT algorithms, cr-MREPT, accurately reconstructs the internal tissue boundaries, however, it faces an artifact which occurs at the regions where the convective field, \

Polarized photon scattering of 52Cr: Determining the parity of dipole states

NASA Astrophysics Data System (ADS)

Krishichayan, Fnu; Bhike, M.; Tornow, W.

2014-03-01

Observation of dipole states in nuclei are important because they provide information on various collective and single-particle nuclear excitation modes, e.g., pygmy dipole resonance (PDR) and spin-flip M1 resonance. The PDR has been extensively studied in the higher and medium mass region, whereas not much information is available around the low mass (A ~ 50) region where, apparently,the PDR starts to form. The present photoresponse of 52Cr has been investigated to test the evolution of the PDR in a nucleus with a small number of excess neutrons as well as to look for spin-flip M1 resonance excitation mode. Spin-1 states in 52Cr between 5.0 to 9.5 MeV excitation energy were excited by exploiting fully polarized photons using the (γ ,γ') nuclear resonance fluorescence technique, a completely model-independent electromagnetic method. The de-excitation γ-rays were detected using a HPGe array. The experiment was carried out using the HIGS facility at TUNL. Results of unambiguous parity determinations of dipole states in 52Cr will be presented.

Anxiety-like behaviour in adult rats perinatally exposed to maternal calorie restriction.

PubMed

Levay, Elizabeth A; Paolini, Antonio G; Govic, Antonina; Hazi, Agnes; Penman, Jim; Kent, Stephen

2008-08-22

Environmental stimuli such as caloric availability during the perinatal period exert a profound influence on the development of an organism. Studies in this domain have focused on the effects of under- and malnutrition while the effects of more mild levels of restriction have not been delineated. Rat dams and their offspring were subjected to one of five dietary regimens: control, CR50% for 3 days preconception, CR25% during gestation, CR25% during lactation, and CR25% during gestation, lactation, and post-weaning (lifelong). The pup retrieval test and maternal observations were conducted during lactation to quantify maternal care. In the pup retrieval test, dams that were concurrently experiencing CR (i.e., from the lactation and lifelong groups) displayed shorter latencies to retrieve all pups than the control and preconception groups and the lactation group constructed better nests than all groups. Adult offspring were tested in three tests of anxiety: the elevated plus maze, open field, and emergence test. No differences were observed in the elevated plus maze; however, in the open field preconception animals made fewer entries and spent more time in the central zone than controls. In addition, preconception offspring exhibited longer latencies to full body emergence, spent less time fully emerged, and spent more time engaged in risk assessment behaviours than all other groups. Offspring from the preconception group were also on average 11% heavier than control rats throughout life and displayed 37% higher serum leptin concentrations than controls. A potential role for leptin in the anxiogenic effect of preconception CR is discussed.

Post-exercise proteinuria in the cadets trained on Special Aerial Gymnastics Instruments.

PubMed

Wochyński, Zbigniew; Sobiech, Krzysztof

2015-01-01

Assessment of the effect of training on Special Aerial Gymnastics Instruments (SAGI) on the urine β-2- microglobulin (β-2M), albumin (ALB), total protein (TP), N-acetyl-β-D-glucosaminidase EC.3.2.1.30 (NAG), expressed as creatinine (Cr) and on the physical fitness of the examined cadets in comparison with the control group. The study involved 55 cadets aged 20, divided into group A (N = 41) trained on SAGI, and group B (N = 14) - a control group. The urine was collected twice: before the training (BT) and after the training (AT) at the start (training I), during (training II), and after completion of the training program (training III). Urine proteins were assayed with commercially available kits. In group A, results obtained in trainings I, II and III showed a statistically significant increase in β-2M/Cr, NAG/Cr, TP/Cr, ALB/Cr indices in AT compared with the baseline BT values. Similarly in group B, a statistically significant increase in β-2M/Cr, NAG/Cr (trainings I, II), TP/Cr, AT compared with the baseline BT values in trainings I, II, and III was noted. Comparison of both groups showed a higher value of the post-exercise proteinuria in group B than in group A. In group A, a significant correlation between TP/Cr vs. ALB/Cr, NAG/Cr vs. TP/Cr, β-2M/Cr vs. TP/Cr, i.e., r = 0.62 at p < 0.001; r = 0.33 at p = 0.03; r = 0.60 at p < 0.001, and r = 0.52 at p < 0.001, respectively, was observed in group A, training III, AT. Assayed urine proteins depend on the intensity of physical exercise, the type of exercise, and the level of physical fitness. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Surface immobilized antibody orientation determined using ToF-SIMS and multivariate analysis.

PubMed

Welch, Nicholas G; Madiona, Robert M T; Payten, Thomas B; Easton, Christopher D; Pontes-Braz, Luisa; Brack, Narelle; Scoble, Judith A; Muir, Benjamin W; Pigram, Paul J

2017-06-01

Antibody orientation at solid phase interfaces plays a critical role in the sensitive detection of biomolecules during immunoassays. Correctly oriented antibodies with solution-facing antigen binding regions have improved antigen capture as compared to their randomly oriented counterparts. Direct characterization of oriented proteins with surface analysis methods still remains a challenge however surface sensitive techniques such as Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) provide information-rich data that can be used to probe antibody orientation. Diethylene glycol dimethyl ether plasma polymers (DGpp) functionalized with chromium (DGpp+Cr) have improved immunoassay performance that is indicative of preferential antibody orientation. Herein, ToF-SIMS data from proteolytic fragments of anti-EGFR antibody bound to DGpp and DGpp+Cr are used to construct artificial neural network (ANN) and principal component analysis (PCA) models indicative of correctly oriented systems. Whole antibody samples (IgG) test against each of the models indicated preferential antibody orientation on DGpp+Cr. Cross-reference between ANN and PCA models yield 20 mass fragments associated with F(ab') 2 region representing correct orientation, and 23 mass fragments associated with the Fc region representing incorrect orientation. Mass fragments were then compared to amino acid fragments and amino acid composition in F(ab') 2 and Fc regions. A ratio of the sum of the ToF-SIMS ion intensities from the F(ab') 2 fragments to the Fc fragments demonstrated a 50% increase in intensity for IgG on DGpp+Cr as compared to DGpp. The systematic data analysis methodology employed herein offers a new approach for the investigation of antibody orientation applicable to a range of substrates. Controlled orientation of antibodies at solid phases is critical for maximizing antigen detection in biosensors and immunoassays. Surface-sensitive techniques (such as ToF-SIMS), capable of direct characterization of surface immobilized and oriented antibodies, are under-utilized in current practice. Selection of a small number of mass fragments for analysis, typically pertaining to amino acids, is commonplace in literature, leaving the majority of the information-rich spectra unanalyzed. The novelty of this work is the utilization of a comprehensive, unbiased mass fragment list and the employment of principal component analysis (PCA) and artificial neural network (ANN) models in a unique methodology to prove antibody orientation. This methodology is of significant and broad interest to the scientific community as it is applicable to a range of substrates and allows for direct, label-free characterization of surface bound proteins. Copyright © 2017 Acta Materialia Inc. All rights reserved.

Urinary levels of nickel and chromium associated with dental restoration by nickel–chromium based alloys

PubMed Central

Chen, Bo; Xia, Gang; Cao, Xin-Ming; Wang, Jue; Xu, Bi-Yao; Huang, Pu; Chen, Yue; Jiang, Qing-Wu

2013-01-01

This paper aims to investigate if the dental restoration of nickel–chromium based alloy (Ni–Cr) leads to the enhanced excretions of Ni and Cr in urine. Seven hundred and ninety-five patients in a dental hospital had single or multiple Ni–Cr alloy restoration recently and 198 controls were recruited to collect information on dental restoration by questionnaire and clinical examination. Urinary concentrations of Ni and Cr from each subject were measure by graphite furnace atomic absorption spectrometry. Compared to the control group, the urinary level of Ni was significantly higher in the patient group of <1 month of the restoration duration, among which higher Ni excretions were found in those with either a higher number of teeth replaced by dental alloys or a higher index of metal crown not covered with the porcelain. Urinary levels of Cr were significantly higher in the three patient groups of <1, 1 to <3 and 3 to <6 months, especially in those with a higher metal crown exposure index. Linear curve estimations showed better relationships between urinary Ni and Cr in patients within 6-month groups. Our data suggested significant increased excretions of urinary Ni and Cr after dental restoration. Potential short- and long-term effects of Ni–Cr alloy restoration need to be investigated. PMID:23579466

Arteriolar and Venular Remodeling Are Differentially Regulated by Bone Marrow-Derived Cell-Specific CX3CR1 and CCR2 Expression

PubMed Central

Meisner, Joshua K.; Song, Ji; Price, Richard J.

2012-01-01

The chemokine receptors CCR2 and CX3CR1 are critical for the recruitment of “inflammatory” and “resident” monocytes, respectively, subpopulations that differentially affect vascular remodeling in atherosclerosis. Here, we tested the hypothesis that bone marrow-derived cell (BMC)-specific CCR2 and CX3CR1 differentially control venular and arteriolar remodeling. Venular and arteriolar lumenal remodeling were observed by intravital microscopy in mice with either CCR2 or CX3CR1 deficient BMCs after implantation of a dorsal skinfold window chamber, a model in which arterioles and venules lumenally enlarge in wild-type (WT) mice. Arteriolar remodeling was abolished in mice with either CCR2 or CX3CR1-deficient BMCs. In contrast, the loss of CX3CR1 from BMCs, but not CCR2, significantly reduced small venule remodeling compared to WT controls. We conclude that microvascular remodeling is differentially regulated by BMC-expressed chemokine receptors. Both CCR2 and CX3CR1 regulate arteriole growth; however, only BMC-expressed CX3CR1 impacts small venule growth. These findings may provide a basis for additional investigations aimed at determining how patterns of monocyte subpopulation recruitment spatially influence microvascular remodeling. PMID:23029475

Spectra of High-Ionization Seyfert 1 Galaxies: Implications for the Narrow-Line Region

NASA Technical Reports Server (NTRS)

Moore, David; Cohen, Ross D.; Marcy, Geoffrey W.

1996-01-01

We present line profiles and profile parameters for the Narrow-Line Regions (NLRs) of six Seyfert 1 galaxies with high-ionization lines: MCG 8-11-11, Mrk 79, Mrk 704, Mrk 841, NGC 4151, and NGC 5548. The sample was chosen primarily with the goal of obtaining high-quality [Fe VII] lambda6087 and, when possible, [Fe X] lambda6374 profiles to determine if these lines are more likely formed in a physically distinct 'coronal line region' or are formed throughout the NLR along with lines of lower critical density (n(sub cr)) and/or Ionization Potential (IP). We discuss correlations of velocity shift and width with n(sub cr) and IP. In some objects, lines of high IP and/or n(sub cr) are systematically broader than those of low IP/n(sub cr). Of particular interest, however, are objects that show no correlations of line width with either IP or n(sub cr). In these objects, lines of high and low IP/n(sub cr), are remarkably similar, which is difficult to reconcile with the classical picture of the NLR, in which lines of high and low IP/n(sub cr) are formed in physically distinct regions. We argue for similar spatial extents for the flux in lines with similar profiles. Here, as well as in a modeling-oriented companion paper, we develop further an idea suggested by Moore & Cohen that objects that do and do not show line width correlations with IP/n(sub cr) can both be explained in terms of a single NLR model with only a small difference in the cloud column density distinguishing the two types of object. Overall, our objects do not show correlations between the Full Width at Half-Maximum (FWHM) and IP and/or n(sub cr). The width must be defined by a parameter that is sensitive to extended profile wings in order for the correlations to result. We present models in which FWHM correlations with IP and/or n(sub cr) result only after simulating the lower spectral resolution used in previous observational studies. The models that simulate the higher spectral resolution of our observational study produce line width correlations only if the width is defined by a parameter that is more sensitive to extended profile wings than is the FWHM. Our sample of six objects is in effect augmented by incorporating the larger sample (16 objects) of Veilleux into some of our discussion. This paper focuses on new interpretations of NLR emission-line spectra and line profiles that stem directly from the observations. Paper 2 focuses on modeling and complements this paper by illustrating explicitly the effects that spatial variations in electron density, ionization parameter, and column density have on model profiles. By comparing model profiles with the observed profiles presented here, as well as with those presented by Veilleux, Paper 2 yields insight into how the electron density, ionization parameter, and column density likely vary throughout the NLR.

Assessment of heavy metal pollution and human health risk in urban soils of steel industrial city (Anshan), Liaoning, Northeast China.

PubMed

Qing, Xiao; Yutong, Zong; Shenggao, Lu

2015-10-01

The purpose of this study was to determine the concentrations and health risk of heavy metals in urban soils from a steel industrial district in China. A total of 115 topsoil samples from Anshan city, Liaoning, Northeast China were collected and analyzed for Cr, Cd, Pb, Zn, Cu, and Ni. The geoaccumulation index (Igeo), pollution index (PI), and potential ecological risk index (PER) were calculated to assess the pollution level in soils. The hazard index (HI) and carcinogenic risk (RI) were used to assess human health risk of heavy metals. The average concentration of Cr, Cd, Pb, Zn, Cu, and Ni were 69.9, 0.86, 45.1, 213, 52.3, and 33.5mg/kg, respectively. The Igeo and PI values of heavy metals were in the descending order of Cd>Zn>Cu>Pb>Ni>Cr. Higher Igeo value for Cd in soil indicated that Cd pollution was moderate. Pollution index indicated that urban soils were moderate to highly polluted by Cd, Zn, Cu, and Pb. The spatial distribution maps of heavy metals revealed that steel industrial district was the contamination hotspots. Principal component analysis (PCA) and matrix cluster analysis classified heavy metals into two groups, indicating common industrial sources for Cu, Zn, Pb, and Cd. Matrix cluster analysis classified the sampling sites into four groups. Sampling sites within steel industrial district showed much higher concentrations of heavy metals compared to the rest of sampling sites, indicating significant contamination introduced by steel industry on soils. The health risk assessment indicated that non-carcinogenic values were below the threshold values. The hazard index (HI) for children and adult has a descending order of Cr>Pb>Cd>Cu>Ni>Zn. Carcinogenic risks due to Cr, Cd, and Ni in urban soils were within acceptable range for adult. Carcinogenic risk value of Cr for children is slightly higher than the threshold value, indicating that children are facing slight threat of Cr. These results provide basic information of heavy metal pollution control and environment management in steel industrial regions. Copyright © 2015 Elsevier Inc. All rights reserved.

Quantitative assessment of atmospheric emissions of toxic heavy metals from anthropogenic sources in China: historical trend, spatial variation distribution, uncertainties and control policies

NASA Astrophysics Data System (ADS)

Tian, H. Z.; Zhu, C. Y.; Gao, J. J.; Cheng, K.; Hao, J. M.; Wang, K.; Hua, S. B.; Wang, Y.; Zhou, J. R.

2015-04-01

Anthropogenic atmospheric emissions of typical toxic heavy metals have received worldwide concerns due to their adverse effects on human health and the ecosystem. By determining the best available representation of time-varying emission factors with S-shape curves, we established the multiyear comprehensive atmospheric emission inventories of 12 typical toxic heavy metals (Hg, As, Se, Pb, Cd, Cr, Ni, Sb, Mn, Co, Cu and Zn) from primary anthropogenic activities in China for the period of 1949-2012 for the first time. Further, we allocated the annual emissions of these heavy metals in 2010 at a high spatial resolution of 0.5° × 0.5° grid with ArcGIS methodology and surrogate indexes, such as regional population and gross domestic product (GDP). Our results show that the historical emissions of Hg, As, Se, Cd, Cr, Ni, Sb, Mn, Co, Cu and Zn during the period of 1949-2012, have been increased by about 22-128 times at an annual average growth rate of 5.1-8.0%, amounting to about 79 570 t in 2012. Nonferrous metal smelting, coal combustion of industrial boilers, brake and tyre wear, and ferrous metals smelting represent the dominant sources for Hg / Cd, As / Se / Pb / Cr / Ni / Mn / Co, Sb / Cu, and Zn, respectively. In terms of spatial variation, the majority of emissions were concentrated in relatively developed regions, especially for the northern, eastern and southern coastal regions. In addition, because of the flourishing nonferrous metals smelting industry, several southwestern and central-southern provinces play a prominent role in some specific toxic heavy metals emissions, like Hg in Guizhou and As in Yunnan. Finally, integrated countermeasures are proposed to minimize the final toxic heavy metals discharge on accounting of the current and future demand of energy-saving and pollution reduction in China.

Assessment of Anterior Cingulate Cortex (ACC) and Left Cerebellar Metabolism in Asperger's Syndrome with Proton Magnetic Resonance Spectroscopy (MRS).

PubMed

Goji, Aya; Ito, Hiromichi; Mori, Kenji; Harada, Masafumi; Hisaoka, Sonoka; Toda, Yoshihiro; Mori, Tatsuo; Abe, Yoko; Miyazaki, Masahito; Kagami, Shoji

2017-01-01

Proton magnetic resonance spectroscopy (1H MRS) is a noninvasive neuroimaging method to quantify biochemical metabolites in vivo and it can serve as a powerful tool to monitor neurobiochemical profiles in the brain. Asperger's syndrome (AS) is a type of autism spectrum disorder, which is characterized by impaired social skills and restrictive, repetitive patterns of interest and activities, while intellectual levels and language skills are relatively preserved. Despite clinical aspects have been well-characterized, neurometabolic profiling in the brain of AS remains to be clear. The present study used proton magnetic resonance spectroscopy (1H MRS) to investigate whether pediatric AS is associated with measurable neurometabolic abnormalities that can contribute new information on the neurobiological underpinnings of the disorder. Study participants consisted of 34 children with AS (2-12 years old; mean age 5.2 (±2.0); 28 boys) and 19 typically developed children (2-11 years old; mean age 5.6 (±2.6); 12 boys) who served as the normal control group. The 1H MRS data were obtained from two regions of interest: the anterior cingulate cortex (ACC) and left cerebellum. In the ACC, levels of N-acetylaspartate (NAA), total creatine (tCr), total choline-containing compounds (tCho) and myo-Inositol (mI) were significantly decreased in children with AS compared to controls. On the other hand, no significant group differences in any of the metabolites were found in the left cerebellum. Neither age nor sex accounted for the metabolic findings in the regions. The finding of decreased levels of NAA, tCr, tCho, and mI in the ACC but not in left cerebellar voxels in the AS, suggests a lower ACC neuronal density in the present AS cohort compared to controls.

Towards new constraints on the impacts of fires on air quality and the nitrogen cycle: Extending the nadir satellite record of peroxyacetyl nitrate (PAN) with CrIS

NASA Astrophysics Data System (ADS)

Fischer, E. V.; Payne, V.; Kulawik, S. S.; Fu, D.

2017-12-01

Peroxyacetyl nitrate (PAN) plays a critical role both in atmospheric chemistry and in the redistribution of nitrogen in the troposphere. As a thermally unstable reservoir for nitrogen oxide radicals (NOx) PAN allows NOxto be transported large distances from the original source, thereby extending the range of air quality impacts from fires. Satellite measurements of PAN from the nadir-viewing Aura Tropospheric Emission Spectrometer (TES) have shown large enhancements in PAN associated with fires, and have recently been used to shed new light on the role of fires, PAN precursor emissions and dynamics on the global distribution of PAN and long-range transport of ozone. TES PAN retrievals have also been used to explore interannual variability in PAN mixing ratios in the Western US. The Cross-track Infrared Sounder (CrIS) on S-NPP and the upcoming JPSS series provides a means to continue the satellite record of PAN from the nadir view, with increased spatial coverage. Retrievals of PAN from TES have so far relied on the PAN absorption feature centered at 1150 cm-1, a spectral region not covered by CrIS. Our team has recently developed an approach that would allow the use of another PAN spectral feature centered at 790 cm-1, a spectral region that is covered by CrIS. Here, we apply this approach to CrIS spectra and compare the characteristics of the CrIS PAN retrievals, including vertical sensitivity and uncertainty estimates, with those of the TES PAN product. The CrIS PAN measurements can offer improved spatial coverage, extend the existing satellite PAN record and provide new opportunities for validation of satellite PAN retrievals.

Toward Rechargeable Persistent Luminescence for the First and Third Biological Windows via Persistent Energy Transfer and Electron Trap Redistribution.

PubMed

Xu, Jian; Murata, Daisuke; Ueda, Jumpei; Viana, Bruno; Tanabe, Setsuhisa

2018-05-07

Persistent luminescence (PersL) imaging without real-time external excitation has been regarded as the next generation of autofluorescence-free optical imaging technology. However, to achieve improved imaging resolution and deep tissue penetration, developing new near-infrared (NIR) persistent phosphors with intense and long duration PersL over 1000 nm is still a challenging but urgent task in this field. Herein, making use of the persistent energy transfer process from Cr 3+ to Er 3+ , we report a novel garnet persistent phosphor of Y 3 Al 2 Ga 3 O 12 codoped with Er 3+ and Cr 3+ (YAG G:Er-Cr), which shows intense Cr 3+ PersL (∼690 nm) in the deep red region matching well with the first biological window (NIR-I, 650-950 nm) and Er 3+ PersL (∼1532 nm) in the NIR region matching well with the third biological window (NIR-III, 1500-1800 nm). The optical imaging through raw-pork tissues (thickness of 1 cm) suggests that the emission band of Er 3+ can achieve higher spatial resolution and more accurate signal location than that of Cr 3+ due to the reduced light scattering at longer wavelengths. Furthermore, by utilizing two independent electron traps with two different trap depths in YAG G:Er-Cr, the Cr 3+ /Er 3+ PersL can even be recharged in situ by photostimulation with 660 nm LED thanks to the redistribution of trapped electrons from the deep trap to the shallow one. Our results serve as a guide in developing promising NIR (>1000 nm) persistent phosphors for long-term optical imaging.

Development of oxidation resistance in thoriated nickel-chromium base alloys

NASA Technical Reports Server (NTRS)

Seltzer, M. S.; Wilcox, B. A.; Jaffee, R. I.; Stringer, J.

1971-01-01

A pack process was developed which permits the introduction of nearly six weight percent aluminum into solid solution in the near-surface region of TDNiCr (Ni-20Cr-2ThO2. At this aluminum concentration an adherent alumina scale is produced on the alloy surface upon exposure to an environment of 1330 n/sq m (10 torr) or 101,000 n/sq m (760 torr) air at temperatures of 1093 C (2000 F) and 1204 C (2200 F). Room temperature mechanical properties of the aluminized alloys compare favorably with those of TDNiCr as received. While diffusivities for aluminum are a factor of three higher than those for chromium in TDNiCr or Ni-20Cr, the diffusion rates are similar for either of these elements in the thoriated or unthoriated alloy for a given temperature and grain size.

Fermi large area telescope study of cosmic rays and the interstellar medium in nearby molecular clouds

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ackermann, M.; Ajello, M.; Allafort, A.

Here, we report an analysis of the interstellar γ-ray emission from the Chamaeleon, R Coronae Australis (R CrA), and Cepheus and Polaris flare regions with the Fermi Large Area Telescope. They are among the nearest molecular cloud complexes, within ~300 pc from the solar system. The γ-ray emission produced by interactions of cosmic rays (CRs) and interstellar gas in those molecular clouds is useful to study the CR densities and distributions of molecular gas close to the solar system. The obtained γ-ray emissivities above 250 MeV are (5.9 ± 0.1stat +0.9 –1.0sys) × 10 –27 photons s –1 sr –1more » H-atom –1, (10.2 ± 0.4 stat +1.2 –1.7sys) × 10 –27 photons s –1 sr –1 H-atom –1, and (9.1 ± 0.3 stat +1.5 –0.6sys) × 10 –27 photons s –1 sr–1 H-atom–1 for the Chamaeleon, R CrA, and Cepheus and Polaris flare regions, respectively. Whereas the energy dependences of the emissivities agree well with that predicted from direct CR observations at the Earth, the measured emissivities from 250 MeV to 10 GeV indicate a variation of the CR density by ~20% in the neighborhood of the solar system, even if we consider systematic uncertainties. Furthermore, we found that the molecular mass calibrating ratio, X CO = N(H 2)/W CO, was (0.96 ± 0.06 stat +0.15 –0.12sys) × 10 20 H 2-molecule cm –2 (K km s –1) –1, (0.99 ± 0.08 stat +0.18 –0.10sys) × 10 20 H 2-molecule cm –2 (K km s –1) –1, and (0.63 ± 0.02 stat +0.09 –0.07sys) × 10 20 H 2-molecule cm –2 (K km s –1) –1 for the Chamaeleon, R CrA, and Cepheus and Polaris flare regions, respectively, suggesting a variation of X CO in the vicinity of the solar system. The obtained values of X CO, the masses of molecular gas traced by W CO in the Chamaeleon, R CrA, and Cepheus and Polaris flare regions are estimated to be ~5 × 10 3 M ,⊙ ~10 3 M ,⊙ and ~3.3 × 10 4 M ,⊙ respectively. A comparable amount of gas not traced well by standard H I and CO surveys is found in the regions investigated.« less

Fermi large area telescope study of cosmic rays and the interstellar medium in nearby molecular clouds

DOE PAGES

Ackermann, M.; Ajello, M.; Allafort, A.; ...

2012-07-23

Here, we report an analysis of the interstellar γ-ray emission from the Chamaeleon, R Coronae Australis (R CrA), and Cepheus and Polaris flare regions with the Fermi Large Area Telescope. They are among the nearest molecular cloud complexes, within ~300 pc from the solar system. The γ-ray emission produced by interactions of cosmic rays (CRs) and interstellar gas in those molecular clouds is useful to study the CR densities and distributions of molecular gas close to the solar system. The obtained γ-ray emissivities above 250 MeV are (5.9 ± 0.1stat +0.9 –1.0sys) × 10 –27 photons s –1 sr –1more » H-atom –1, (10.2 ± 0.4 stat +1.2 –1.7sys) × 10 –27 photons s –1 sr –1 H-atom –1, and (9.1 ± 0.3 stat +1.5 –0.6sys) × 10 –27 photons s –1 sr–1 H-atom–1 for the Chamaeleon, R CrA, and Cepheus and Polaris flare regions, respectively. Whereas the energy dependences of the emissivities agree well with that predicted from direct CR observations at the Earth, the measured emissivities from 250 MeV to 10 GeV indicate a variation of the CR density by ~20% in the neighborhood of the solar system, even if we consider systematic uncertainties. Furthermore, we found that the molecular mass calibrating ratio, X CO = N(H 2)/W CO, was (0.96 ± 0.06 stat +0.15 –0.12sys) × 10 20 H 2-molecule cm –2 (K km s –1) –1, (0.99 ± 0.08 stat +0.18 –0.10sys) × 10 20 H 2-molecule cm –2 (K km s –1) –1, and (0.63 ± 0.02 stat +0.09 –0.07sys) × 10 20 H 2-molecule cm –2 (K km s –1) –1 for the Chamaeleon, R CrA, and Cepheus and Polaris flare regions, respectively, suggesting a variation of X CO in the vicinity of the solar system. The obtained values of X CO, the masses of molecular gas traced by W CO in the Chamaeleon, R CrA, and Cepheus and Polaris flare regions are estimated to be ~5 × 10 3 M ,⊙ ~10 3 M ,⊙ and ~3.3 × 10 4 M ,⊙ respectively. A comparable amount of gas not traced well by standard H I and CO surveys is found in the regions investigated.« less

Effects of Zolpidem CR on Sleep and Nocturnal Ventilation in Patients with Heart Failure.

PubMed

Gatti, Rodrigo C; Burke, Patrick R; Otuyama, Leonardo J; Almeida, Dirceu R; Tufik, Sergio; Poyares, Dalva

2016-08-01

This study aimed to evaluate the effects of zolpidem CR (controlled release) on sleep and nocturnal ventilation in patients with congestive heart failure, a population at risk for insomnia and poor sleep quality. Fifteen patients with heart failure (ischemic cardiomyopathy) and ejection fraction ≤ 45% in NYHA functional class I or II were evaluated with full polysomnography in a placebo-controlled, double-blind, randomized trial. Patients underwent three tests: (1) baseline polysomnography and, after randomization, (2) a new test with zolpidem CR 12.5 mg or placebo, and after 1 week, (3) a new polysomnography, crossing the "medication" used. A 16% increase in total sleep time was found with the use of zolpidem CR and an increase in stage 3 NREM sleep (slow wave sleep). The apnea hypopnea index (AHI) did not change with zolpidem CR even after controlling for supine position; however, a slight but significant decrease was observed in lowest oxygen saturation compared with baseline and placebo conditions (83.60 ± 5.51; 84.43 ± 3.80; 80.71 ± 5.18, P = 0.002). Zolpidem CR improved sleep structure in patients with heart failure, did not change apnea hypopnea index, but slightly decreased lowest oxygen saturation. © 2016 Associated Professional Sleep Societies, LLC.

Oxidation products of Inconel alloys 600 and 690 in hydrogenated steam environments and their role in stress corrosion cracking

NASA Astrophysics Data System (ADS)

Ferguson, J. Bryce

Inconel Alloys 600 and 690 are used extensively in components of Nuclear Pressurized Water Reactors (PWR) in the primary water loop which consists of H2 supersaturated steam. Alloy 600 has been found to crack intergranularly when exposed to primary water conditions. Alloy 690 was designed as a replacement and is generally regarded as immune to cracking. There is no consensus as to the mechanism which is responsible for cracking or the lack thereof in these alloys. In this work thermodynamic arguments for the stability of Ni and Cr compounds developed under pressurized water reactor environments ( PH2O and PH2 ) were experimentally tested. A mechanism is proposed to explain crack initiation and propagation alloy 600 along the grain boundaries where Cr2O3 has formed from the leaching of Cr from the matrix leaving behind a porous Ni-rich region. The mechanism is based on the thermodynamic potential for the transformation of a protective NiO surface layer into an amorphous non-protective Ni(OH)2 gel. This gel would also form along the grain boundaries and when hydrogenated steam reaches the porous Ni-rich regions. Crack initiation is then favored by tensile stressing of the grain boundary regions which can easily rupture the gelatinous film. The leaching of matrix Cr to form non-protective CrOOH gel at the crack tip followed by the exposure of fresh porous Ni to the environment also explains crack propagation in inconel alloy 600. The proposed crack initiation mechanism is not expected to occur in alloy 690 where a protective Cr2O 3 film covers the entire metal surface. However, crack propagation along the grain boundaries in alloy 600 and pre-cracked alloy 690 is expected to be active as hydroxide-forming reactions weaken the material at the grain boundaries.

Effects of self-hypnosis training and cognitive restructuring on daily pain intensity and catastrophizing in individuals with multiple sclerosis and chronic pain.

PubMed

Jensen, Mark P; Ehde, Dawn M; Gertz, Kevin J; Stoelb, Brenda L; Dillworth, Tiara M; Hirsh, Adam T; Molton, Ivan R; Kraft, George H

2011-01-01

Fifteen adults with multiple sclerosis were given 16 sessions of treatment for chronic pain that included 4 sessions each of 4 different treatment modules: (a) an education control intervention; (b) self-hypnosis training (HYP); (c) cognitive restructuring (CR); and (d) a combined hypnosis-cognitive restructuring intervention (CR-HYP). The findings supported the greater beneficial effects of HYP, relative to CR, on average pain intensity. The CR-HYP treatment appeared to have beneficial effects greater than the effects of CR and HYP alone. Future research examining the efficacy of an intervention that combines CR and HYP is warranted.

Addition of DNA to CrVI and Cytochrome b5 Containing Proteoliposomes Leads to Generation of DNA Strand Breaks and CrIII Complexes

PubMed Central

Borthiry, Griselda R.; Antholine, William E.; Myers, Judith M.; Myers, Charles R.

2009-01-01

Chromium (Cr) is a cytotoxic metal that can be associated with a variety of types of DNA damage, including Cr-DNA adducts and strand breaks. Prior studies with purified human cytochrome b5 and NADPH :P450 reductase in reconstituted proteoliposomes (PLs) demonstrated rapid reduction of CrVI (hexavalent chromium, as CrO42− ), and the generation of CrV, superoxide (O2·−) , and hydroxyl radical (HO˙). Studies reported here examined the potential for the species produced by this system to interact with DNA. Strand breaks of purified plasmid DNA increased over time aerobically, but were not observed in the absence of O2. CrV is formed under both conditions, so the breaks are not mediated directly by CrV. The aerobic strand breaks were significantly prevented by catalase and EtOH, but not by the metal chelator diethylenetriaminepentaacetic acid (DTPA), suggesting that they are largely due to HO˙ from Cr-mediated redox cycling. EPR was used to assess the formation of Cr-DNA complexes. Following a 10-min incubation of PLs, CrO42− , and plasmid DNA, intense EPR signals at g = 5.7and g = 5.0 were observed. These signals are attributed to specific CrIII complexes with large zero field splitting (ZFS). Without DNA, the signals in the g = 5 region were weak. The large ZFS signals were not seen, when CrIIICl3 was incubated with DNA, suggesting that the CrIII–DNA interactions are different when generated by the PLs. After 24 h, a broad signal at g = 2 is attributed to CrIII complexes with a small ZFS. This g = 2 signal was observed without DNA, but it was different from that seen with plasmid. It is concluded that EPR can detect specific CrIII complexes that depend on the presence of plasmid DNA and the manner in which the CrIII is formed. PMID:18729091

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roy, Ram Vinod; Pratheeshkumar, Poyil; Son, Yong-O

Hexavalent chromium (Cr(VI)) is classified as a human carcinogen. Cr(VI) has been associated with adenocarcinomas and squamous cell carcinoma of the lung. The present study shows that acute Cr(VI) treatment in human bronchial epithelial cells (BEAS-2B) increased inflammatory responses (TNF-α, COX-2, and NF-кB/p65) and expression of Nrf2. Cr(VI)-induced generation of reactive oxygen species (ROS) are responsible for increased inflammation. Despite the fact that Nrf2 is a master regulator of response to oxidative stress, silencing of Nrf2 in the acute Cr(VI) treatment had no effect on Cr(VI)-induced inflammation. In contrast, in Cr(VI)-transformed (CrT) cells, Nrf2 is constitutively activated. Knock-down of thismore » protein resulted in decreased inflammation, while silencing of SOD2 and CAT had no effect in the expression of these inflammatory proteins. Results obtained from the knock-down of Nrf2 in CrT cells are very different from the results obtained in the acute Cr(VI) treatment. In BEAS-2B cells, knock-down of Nrf2 had no effect in the inflammation levels, while in CrT cells a decrease in the expression of inflammation markers was observed. These results indicate that before transformation, ROS plays a critical role while Nrf2 not in Cr(VI)-induced inflammation, whereas after transformation (CrT cells), Nrf2 is constitutively activated and this protein maintains inflammation while ROS not. Constitutively high levels of Nrf2 in CrT binds to the promoter regions of COX-2 and TNF-α, leading to increased inflammation. Collectively, our results demonstrate that before cell transformation ROS are important in Cr(VI)-induced inflammation and after transformation a constitutively high level of Nrf2 is important. - Highlights: • Cr(VI)-induced ROS increased inflammation, while Nrf2 had no effect. • In the CrT cells knock-down of Nrf2 resulted in decreased inflammation. • Mechanistic differences in regulating Cr(VI)-induced inflammation.« less

Recent progress in the development of carbonate-intercalated Zn/Cr LDH as a novel photocatalyst for hydrogen evolution aimed at the utilization of solar light.

PubMed

Parida, Kulamani; Mohapatra, Lagnamayee

2012-01-28

A series of novel photocatalysts Zn/Cr LDH with different Zn/Cr molar ratios (2 : 1, 3 : 1, 4 : 1 and 2 : 1-CO(3)) were fabricated by a co-precipitation method and evaluated for photodecomposition of water using visible light irradiation. Various characterization methods were employed to investigate the structures, morphologies and photocatalytic properties. In comparison to Zn/Cr (2 : 1) LDH, Zn/Cr-CO(3) (2 : 1) LDH extends the absorption edges to the visible region and exhibits good photocatalytic activity, even without the assistance of co-catalysts. The visible light photocatalytic activity is ascribed to the charge transfer spectra of octahedral Cr ions in LDH. Zn/Cr-CO(3) LDH shows enhanced photocatalytic activities compared to Zn/Cr LDH as carbonate ions oxidise by holes to form carbonate radicals, inhibit the rapid recombination of e(-) and h(+) charge carriers and thereby suppress the backward reaction to some extent. This work provides a detailed understanding of the semiconductor properties of LDHs for photocatalytical hydrogen evolution.

Effect of Cr doping on the structural, morphological, optical and electrical properties of indium tin oxide films

NASA Astrophysics Data System (ADS)

Mirzaee, Majid; Dolati, Abolghasem

2015-03-01

We report on the preparation and characterization of high-purity chromium (0.5-2.5 at.%)-doped indium tin oxide (ITO, In:Sn = 90:10) films deposited by sol-gel-mediated dip coating. The effects of different Cr-doping contents on structural, morphological, optical and electrical properties of the films were characterized by means of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM), UV-Vis spectroscopy and four-point probe methods. XRD showed high phase purity cubic In2O3 and indicated a contraction of the lattice with Cr doping. FESEM micrographs show that grain size decreased with increasing the Cr-doping content. A method to determine chromium species in the sample was developed through the decomposition of the Cr 2 p XPS spectrum in Cr6+ and Cr3+ standard spectra. Optical and electrical studies revealed that optimum opto-electronic properties, including minimum sheet resistance of 4,300 Ω/Sq and an average optical transmittance of 85 % in the visible region with a band gap of 3.421 eV, were achieved for the films doped with Cr-doping content of 2 at.%.

Process for producing Ti-Cr-Al-O thin film resistors

DOEpatents

Jankowski, Alan F.; Schmid, Anthony P.

2001-01-01

Thin films of Ti-Cr-Al-O are used as a resistor material. The films are rf sputter deposited from ceramic targets using a reactive working gas mixture of Ar and O.sub.2. Resistivity values from 10.sup.4 to 10.sup.10 Ohm-cm have been measured for Ti-Cr-Al-O film <1 .mu.m thick. The film resistivity can be discretely selected through control of the target composition and the deposition parameters. The application of Ti-Cr-Al-O as a thin film resistor has been found to be thermodynamically stable, unlike other metal-oxide films. The Ti-Cr-Al-O film can be used as a vertical or lateral resistor, for example, as a layer beneath a field emission cathode in a flat panel display; or used to control surface emissivity, for example, as a coating on an insulating material such as vertical wall supports in flat panel displays.

Flat panel display using Ti-Cr-Al-O thin film

DOEpatents

Jankowski, Alan F.; Schmid, Anthony P.

2002-01-01

Thin films of Ti--Cr--Al--O are used as a resistor material. The films are rf sputter deposited from ceramic targets using a reactive working gas mixture of Ar and O.sub.2. Resistivity values from 10.sup.4 to 10.sup.10 Ohm-cm have been measured for Ti--Cr--Al--O film <1 .mu.m thick. The film resistivity can be discretely selected through control of the target composition and the deposition parameters. The application of Ti--Cr--Al--O as a thin film resistor has been found to be thermodynamically stable, unlike other metal-oxide films. The Ti--Cr--Al--O film can be used as a vertical or lateral resistor, for example, as a layer beneath a field emission cathode in a flat panel display; or used to control surface emissivity, for example, as a coating on an insulating material such as vertical wall supports in flat panel displays.

TI--CR--AL--O thin film resistors

DOEpatents

Jankowski, Alan F.; Schmid, Anthony P.

2000-01-01

Thin films of Ti--Cr--Al--O are used as a resistor material. The films are rf sputter deposited from ceramic targets using a reactive working gas mixture of Ar and O.sub.2. Resistivity values from 10.sup.4 to 10.sup.10 Ohm-cm have been measured for Ti--Cr--Al--O film <1 .mu.m thick. The film resistivity can be discretely selected through control of the target composition and the deposition parameters. The application of Ti--Cr--Al--O as a thin film resistor has been found to be thermodynamically stable, unlike other metal-oxide films. The Ti--Cr--Al--O film can be used as a vertical or lateral resistor, for example, as a layer beneath a field emission cathode in a flat panel display; or used to control surface emissivity, for example, as a coating on an insulating material such as vertical wall supports in flat panel displays.

Controlled release levodopa/carbidopa (Sinemet CR4) in Parkinson's disease--an open evaluation of efficacy and safety.

PubMed

Bulling, M T; Wing, L M; Burns, R J

1991-08-01

Twenty patients with moderately severe Parkinson's disease entered an open study of the efficacy and safety of a slow release preparation containing levodopa 200 mg and carbidopa 50 mg per tablet ('Sinemet CR4'). Following an initial four week baseline stabilisation period on conventional 'Sinemet' tablets, the patients were transferred to 'Sinemet CR4' and observed at intervals over the next 12 months. Fifteen patients completed the full year observation period. When compared with the baseline period, treatment with 'Sinemet CR4' was associated with longer periods of functional improvement and less fluctuation of response following each dose. The median (range) dose frequency was reduced from three (three-12) to two (two-seven) times daily (p less than 0.001) on 'Sinemet CR4' although median (range) total daily dose of levodopa was increased from 700 (375-2525) to 800 (400-2800) mg without any increase in adverse effects. Three patients developed peripheral neuropathy while receiving Sinemet CR4, but the association with this therapy is unclear. Overall 'Sinemet CR4' allowed a longer dosage interval and provided more stable control of disease manifestations than conventional 'Sinemet'.

Efficacy of group cognitive rehabilitation therapy in multiple sclerosis.

PubMed

Mani, A; Chohedri, E; Ravanfar, P; Mowla, A; Nikseresht, A

2018-06-01

Cognitive impairment occurs in 40%-65% of patients with multiple sclerosis (MS). Several techniques for cognitive rehabilitation (CR) in these patients have been evaluated; however, the results have been controversial. In this study, we investigated the efficacy of group compensatory CR in patients with MS-related cognitive impairment. Thirty-four female patients with diagnosed relapsing-remitting MS and evidence of impaired cognitive function were included and randomized to intervention (n = 17) and control (n = 17) groups. CR intervention consisted of eight 2-hour sessions of comprehensive group CR over a 4-week period that focused on improvement of memory, attention, and executive function. As placebo, the control group received the same number of non-therapeutic group sessions. Assessment of cognitive function was performed before intervention (pretest), at the end of intervention (post-test), and 3 months later (follow-up). The study population included 34 patients with a mean age of 35.5 years. Statistical comparison of memory assessments at 3-month follow-up showed significantly higher scores in the CR group than in the control group (93.33 vs 86.40 for Addenbrooke's Cognitive Examination test and 16.58 vs 12.00 for visual memory, 19.32 vs 14.05 for verbal memory, and 51.28 vs 44.41 for general scores on the Memory Functioning Questionnaire test, respectively). Wisconsin card sorting test score comparison showed significantly lower total time consumption in the CR group than in the control group (308.1 vs 340.8 seconds, respectively). Behavior rating inventory of executive function-adult scores in all four subtests were significantly higher in the CR group than in the control group (40.25 vs 55.4 for behavioral regulation index, 51.16 vs 68.6 for metacognition index, and 97.41 vs 124.00 for global executive composite, respectively). Attention was the only domain in which we did not observe any significant variation between groups in terms of post-test and follow-up scores. This study supports the efficacy of group CR in the improvement of cognitive function in patients with MS. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Effects of Zolpidem CR on Sleep and Nocturnal Ventilation in Patients with Heart Failure

PubMed Central

Gatti, Rodrigo C.; Burke, Patrick R.; Otuyama, Leonardo J.; Almeida, Dirceu R.; Tufik, Sergio; Poyares, Dalva

2016-01-01

Study Objective: This study aimed to evaluate the effects of zolpidem CR (controlled release) on sleep and nocturnal ventilation in patients with congestive heart failure, a population at risk for insomnia and poor sleep quality. Methods: Fifteen patients with heart failure (ischemic cardiomyopathy) and ejection fraction ≤ 45% in NYHA functional class I or II were evaluated with full polysomnography in a placebo-controlled, double-blind, randomized trial. Patients underwent three tests: (1) baseline polysomnography and, after randomization, (2) a new test with zolpidem CR 12.5 mg or placebo, and after 1 week, (3) a new polysomnography, crossing the “medication” used. Results: A 16% increase in total sleep time was found with the use of zolpidem CR and an increase in stage 3 NREM sleep (slow wave sleep). The apnea hypopnea index (AHI) did not change with zolpidem CR even after controlling for supine position; however, a slight but significant decrease was observed in lowest oxygen saturation compared with baseline and placebo conditions (83.60 ± 5.51; 84.43 ± 3.80; 80.71 ± 5.18, P = 0.002). Conclusion: Zolpidem CR improved sleep structure in patients with heart failure, did not change apnea hypopnea index, but slightly decreased lowest oxygen saturation. Citation: Gatti RC, Burke PR, Otuyama LJ, Almeida DR, Tufik S, Poyares D. Effects of zolpidem CR on sleep and nocturnal ventilation in patients with heart failure. SLEEP 2016;39(8):1501–1505. PMID:27166233

N-acetylaspartate (NAA) correlates inversely with cannabis use in a frontal language processing region of neocortex in MDMA (Ecstasy) polydrug users: a 3 T magnetic resonance spectroscopy study.

PubMed

Cowan, Ronald L; Joers, James M; Dietrich, Mary S

2009-03-01

Impaired verbal memory is common in MDMA (Ecstasy) polydrug users. The contributions of Ecstasy or polydrug exposure to reduced verbal memory are unclear, as is the neural basis for this cognitive deficit. Ecstasy users have reduced gray matter in brain regions mediating verbal memory (BA 18, 21 and 45). N-acetylaspartate (NAA) as a neuronal marker and myoinositol (mI) as a glial marker are inconsistently affected in Ecstasy users. We used 3 T MRS in 17 recreational drug users to test the hypothesis that Ecstasy polydrug use would be associated with altered NAA or mI in BA 18, 21 and 45. No effects were seen for mI. Metabolite ratios for NAA (mean+/-SD) were: BA 18-NAA/Cr (2.030+/-0.188); BA 21-NAA/Cr (1.861+/-0.325); BA 45-NAA/Cr (1.925+/-0.329). Lifetime cannabis use was significantly associated with BA 45 NAA/Cr (r=-0.687, p=0.014) but not with NAA in BA 18 or 21. In contrast, there were no statistically significant associations for lifetime use of Ecstasy, alcohol, or cocaine with NAA. These findings suggest that cannabis use may contribute to altered neuronal integrity in Ecstasy polydrug users in a brain region associated with verbal memory processing.

N-acetylaspartate (NAA) correlates inversely with cannabis use in a frontal language processing region of neocortex in MDMA (Ecstasy) Polydrug Users: a 3 Tesla Magnetic Resonance Spectroscopy Study

PubMed Central

Cowan, Ronald L; Joers, James M; Dietrich, Mary S

2015-01-01

Impaired verbal memory is common in MDMA (Ecstasy) polydrug users. The contributions of Ecstasy or polydrug exposure to reduced verbal memory are unclear, as is the neural basis for this cognitive deficit. Ecstasy users have reduced gray matter in brain regions mediating verbal memory (BA 18, 21 and 45). N-acetylaspartate (NAA) as a neuronal marker and myoinositol (mI) as a glial marker are inconsistently affected in Ecstasy users. We used 3 Tesla MRS in 17 recreational drug users to test the hypothesis that Ecstasy polydrug use would be associated with altered NAA or mI in BA 18, 21 and 45. No effects were seen for mI. Metabolite ratios for NAA (mean ± SD) were: BA 18--NAA/Cr (2.030 ± 0.188); BA 21--NAA/Cr (1.861 ± 0.325); BA 45--NAA/Cr (1.925 ± 0.329). Lifetime cannabis use was significantly associated with BA 45 NAA/Cr (r = −0.687, p = 0.014) but not with NAA in BA 18 or 21. In contrast, there were no statistically significant associations for lifetime use of Ecstasy, alcohol, or cocaine with NAA. These findings suggest that cannabis use may contribute to altered neuronal integrity in Ecstasy polydrug users in a brain region associated with verbal memory processing. PMID:19032963

Synthesis and energy transfer studies of LaMgAl{sub 11}O{sub 19}:Cr{sup 3+}, Nd{sup 3+} phosphors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhu, Jicheng; Xia, Zhiguo; Liu, Quanlin, E-mail: qlliu@ustb.edu.cn

2016-02-15

Highlights: • Cr{sup 3+}/Nd{sup 3+} co-doped LaMgAl{sub 11}O{sub 19} phosphors were synthesized. • The energy transfer mechanism is ascribed to the dipole–quadrupole interaction. • The materials can convert the UV–vis light into near-infrared emission. - Abstract: Cr{sup 3+}/Nd{sup 3+} co-activated LaMgAl{sub 11}O{sub 19} phosphors have been synthesized by high temperature solid-state method. In the LaMgAl{sub 11}O{sub 19}:Cr{sup 3+}/Nd{sup 3+} system, Cr{sup 3+} can absorb the UV–vis photons (350–650 nm), and then energy transfer takes place between Cr{sup 3+} and Nd{sup 3+}, and finally the samples give near infrared emission originated from Nd{sup 3+}. Energy transfer from Cr{sup 3+} to Nd{supmore » 3+} is discussed via the variations of the lifetime values of Cr{sup 3+}, and the mechanism has been ascribed to the dipole–quadrupole interaction. The absorption of Cr{sup 3+} in the visible region and the following energy transfer from Cr{sup 3+} to Nd{sup 3+} indicated that the material can potentially serve as spectral convertors to improve the photovoltaic conversion efficiency of silicon-based solar cell.« less

Synthesis and study of electronic state of Sr2CrO2Co2As2 with CoAs conduction layers

NASA Astrophysics Data System (ADS)

Suzuki, Atsushi; Ohta, Hiroto; Aruga Katori, Hiroko

2017-06-01

We successfully synthesized a new member of compounds with the CoAs layer, Sr2CrO2Co2As2, and its partially substituted systems Sr2CrO2(Tmx Co1- x )2As2 (Tm = Fe, Ni), and measured magnetization and electric resistivity of these polycrystalline compounds. As a result of magnetic measurement for Sr2CrO2Co2As2, magnetic moments of Co do not construct an itinerant electronic ferromagnetism unlike other compounds with the CoPn (Pn=P and As) layers. Both Sr2CrO2(Tmx Co1- x )2As2 with Tm = Fe and Ni also do not show an itinerant electronic ferromagnetism down to 2 K. For each solid solution of Sr2CrO2(Fe x Co1- x )2As2 with x > 0.0, ρ weakly increases with the decrease of T at low temperature region, indicating that the mixed occupancy of Cr and Fe within the conducting layers occurs in Sr2CrO2(Fe x Co1- x )2As2. We conclude that the absence of ferromagnetism in Sr2CrO2Co2As2 is due to the self-electron-doping from Cr to the conduction bands and the attempt to recover the ferromagnetism by the hole-doping effect is prevented by the mixed occupancy of Cr and Fe in Sr2CrO2 (Fe x Co1- x )2As2 with x > 0.0. The result of our structural analysis supports that the disappearance of itinerant electronic ferromagnetism in Sr2CrO2Co2As2 is due to the self-electron-doping from Cr.

The complete mitochondrial genome of the North Chinese Leopard (Panthera pardus japonensis).

PubMed

Dou, Hailong; Feng, Limin; Xiao, Wenhong; Wang, Tianming

2016-01-01

The North Chinese Leopard (Panthera pardus japonensis) is an endemic subspecies of Panthera pardus to China, living in small and isolated populations with a severely fragmented distribution. Here we first sequenced and annotated its complete mitochondrial genome. The total length of the North Chinese Leopard is of 16,966 base pairs that consist of 2 rRNA gene, 22 tRNA genes, 13 protein-coding genes, 1 OLR and 1 control region (CR). The structures of the genomes were highly similar to other Felidae.

Evolution of displacement cascades in Fe-Cr structures with different [001] tilt grain boundaries

NASA Astrophysics Data System (ADS)

Abu-Shams, M.; Haider, W.; Shabib, I.

2017-06-01

Reduced-activation ferritic/martensitic steels of Cr concentration between 2.25 and 12 wt% are candidate structural materials for next-generation nuclear reactors. In this study, molecular dynamics (MD) simulation is used to generate the displacement cascades in Fe-Cr structures with different Cr concentrations by using different primary knock-on atom (PKA) energies between 2 and 10 keV. A concentration-dependent model potential has been used to describe the interactions between Fe and Cr. Single crystals (SCs) of three different coordinate bases (e.g. [310], [510], and [530]) and bi-crystal (BC) structures with three different [001] tilt grain boundaries (GBs) (e.g. Σ5, Σ13, and Σ17) have been simulated. The Wigner-Seitz cell criterion has been used to identify the produced Frenkel pairs. The results show a marked difference between collisions observed in SCs and those in BC structures. The numbers of vacancies and interstitials are found to be significantly higher in BC structures than those found in SCs. The number of point defects exhibits a power relationship with the PKA energies; however, the Cr concentration does not seem to have any influence on the number of survived point defects. In BC models, a large fraction of the total survived point defects (between 59% and 93%) tends accumulate at the GBs, which seem to trap the generated point defects. The BC structure with Σ17 GB is found to trap more defects than Σ5 and Σ13 GBs. The defect trapping is found to be dictated by the crystallographic parameters of the GBs. For all studied GBs, self-interstitial atoms (SIAs) are easily trapped within the GB region than vacancies. An analysis of defect composition reveals an enrichment of Cr in SIAs, and in BC cases, more than half of the Cr-SIAs are found to be located within the GB region.

Exploration and engineering of physical properties in high-quality Sr2CrReO6 epitaxial films

NASA Astrophysics Data System (ADS)

Lucy, Jeremy Matthew

Double perovskites have proven to be highly interesting materials, particularly in the past two decades, with many materials in this family exhibiting strong correlations. These materials are some of many novel complex oxides with potential spintronics application. Sr2CrReO6, in particular, is a double perovskite with one of the highest Curie temperatures of its class (> 620 K in bulk and ~510-600 K in thin films), as well as high spin polarization, ferrimagnetic behavior, and semiconducting properties. This dissertation covers recent work in exploring and tuning physical properties in epitaxial films of Sr2CrReO6. It starts by providing a background for the field of spintronics and double perovskites, bulk and thin film synthesis of Sr2CrReO6, and standard and specialized characterization techniques utilized in both university and national laboratories, and then provides reports of work on Sr2CrReO6 epitaxial films. Examples of exploration and engineering of properties of Sr2CrReO 6 include: (1) tuning of electrical resistivity, such as at T= 7 K by a factor of 18,000%, via control of oxygen partial pressure during film growth; (2) enhancement of interfacial double perovskite ordering, demonstrated with high-angle annular dark-field scanning transmission electron microscopy, via the use of double perovskite buffer layer substrates; (3) measurement of magnetization suppression near film/substrate interfaces via polarized neutron reflectometry, which reveals a reduction of thickness (from 5.6 nm to 3.6 nm) of the magnetically suppressed interface region due to buffer layer enhancement; (4) strain tunability of atomic spin and orbital moments of Cr, Re, and O atoms probed with x-ray magnetic circular dichroism, which demonstrates ferrimagnetic behavior and reveals important magnetic contributions of the oxygen sites (~0.02 muB/site); (5) strain tunability of large magnetocrystalline anisotropy via applied epitaxial strain, revealing anisotropy fields of up to 10s of tesla; and (6) depth-resolved synchrotron x-ray studies of correlated magnetic and structural relaxation in a thick relaxing film. The utilized techniques and demonstrated results for Sr2CrReO6 will hopefully benefit researchers of complex oxide materials and perhaps stimulate further work on this and other related materials.

In-situ XAFS study for calcination process of Cr catalyst supported on γ-Al2O3 and SiO2

NASA Astrophysics Data System (ADS)

Watanabe, T.; Ikeda, K.; Katayama, M.; Inada, Y.

2016-05-01

The catalytic performance is largely affected by the oxidation state of supported Cr species, and its control changes the activity of Cr catalysts and the selectivity of products. In this study, the calcination process of the supported Cr catalysts on γ-Al2O3 and SiO2 was investigated by in-situ XAFS spectroscopy. The hydrate species was first supported by the impregnation method and was converted to CrO3 via Cr2O3 during the calcination process on both supporting materials. It was found that the temperature to complete the oxidation from Cr2O3 to CrO3 on SiO2 was higher than that on γ-Al2O3. The similarity of the interatomic distance between the surface oxygen atoms of the intermediate Cr2O3 species to that of SiO2 contributes to the stabilization of Cr2O3 on SiO2 during the calcination process.

Production and carcase traits in broiler chickens given diets supplemented with inorganic trivalent chromium and an organic acid blend.

PubMed

Samanta, S; Haldar, S; Ghosh, T K

2008-03-01

1. The study was conducted to ascertain the effects of supplemental organic acids and chromium (Cr) on production and carcase traits of broiler chickens. 2. A total of 120 1-d-old broiler chicks were divided into 4 treatment groups in a 2 x 2 factorial design (each treatment group contained 6 replicates with 5 birds per replicate). 3. The diets were supplemented with an organic acid blend containing ortho-phosphoric, formic and propionic acid and calcium propionate (1 g/kg diet) and inorganic trivalent chromium (Cr(3+)) as chromic chloride hexahydrate (0.5 mg/kg diet) either independently or together as a combination for 35 d. 4. Individual supplementation of organic acids and Cr(3+) and their combination significantly improved the food conversion ratio, hot and dressed carcase weight and weight of the wholesale cuts compared to the control group of birds. 5. Organic acids, either independently or along with Cr(3+), increased total accretion of ash in carcase. Protein accretion was improved by dietary Cr(3+) and organic acid supplementation compared to the control group and a further improvement in this regard was observed when Cr(3+) and organic acid were supplemented together. Across the treatment groups meat fat content and fat accretion were lower in birds receiving dietary Cr(3+) supplementation. 6. Circulatory Cr(3+) and meat Cr(3+) concentration increased compared to the other treatment groups when Cr(3+) was supplemented to the birds. 7. It was concluded that, instead of individual supplementation, a combination of Cr(3+) and organic acids may improve the production and carcase traits of broilers more effectively presumably because of an additive effect.

Cognitive reserve as a predictor of two year neuropsychological performance in early onset first-episode schizophrenia.

PubMed

de la Serna, Elena; Andrés-Perpiñá, Susana; Puig, Olga; Baeza, Inmaculada; Bombin, Igor; Bartrés-Faz, David; Arango, Celso; Gonzalez-Pinto, Ana; Parellada, Mara; Mayoral, María; Graell, Montserrat; Otero, Soraya; Guardia, Joan; Castro-Fornieles, Josefina

2013-01-01

The concept of cognitive reserve (CR) has been defined as individual differences in the efficient utilization of brain networks which allow some people to cope better than others with brain pathology. CR has been developed mainly in the field of aging and dementia after it was observed that there appears to be no direct relationship between the degree of brain pathology and the severity of clinical manifestations of this damage. The present study applies the concept of CR to a sample of children and adolescents with a first episode of schizophrenia, aiming to assess the possible influence of CR on neuropsychological performance after two year follow-up, controlling for the influence of clinical psychopathology. 35 patients meeting DSM-IV criteria for schizophrenia or schizoaffective disorder (SSD) and 98 healthy controls (HC) matched for age and gender were included. CR was assessed at baseline, taking into account premorbid IQ, educational-occupational level and leisure activities. Clinical and neuropsychological assessments were completed by all patients at two year follow-up. The CR proxy was able to predict working memory and attention at two year follow-up. Verbal memory and cognitive flexibility were not predicted by any of the variables included in the regression model. The SSD group obtained lower scores than HC on CR. CR measures correctly classified 79.8% of the sample as being SSD or HC. Lower scores on CR were observed in SSD than in HC and the CR measure correctly classified a high percentage of the sample into the two groups. CR may predict SSD performance on working memory and attention tasks. Copyright © 2012 Elsevier B.V. All rights reserved.

Chemoradiotherapy, with adjuvant surgery for local control, confers a durable survival advantage in adenocarcinoma and squamous cell carcinoma of the oesophagus.

PubMed

Bass, G A; Furlong, H; O'Sullivan, K E; Hennessy, T P J; Walsh, T N

2014-04-01

Oesophageal cancer usually presents with systemic disease, necessitating systemic therapy. Neo-adjuvant chemoradiotherapy improves short-term survival, but its long-term impact is disputed because of limited accrual, treatment-protocol heterogeneity and a short follow-up of randomised trials. Long-term results of two simultaneous randomised controlled trials (RCTs) comparing neo-adjuvant chemo-radiotherapy and surgery (MMT) with surgical monotherapy were examined, and the response of adenocarcinoma (AC) and squamous cell carcinoma (SCC) to identical regimens compared. Between 1990 and 1997, two RCTs were undertaken on 211 patients. Patients with AC (n=113) or SCC (n=98) were separately-randomised to identical protocols of MMT or surgical monotherapy. 211 patients were followed to 206 months; 104 patients were randomised to MMT (58 AC and 46 SCC, respectively) and 107 to surgery. MMT provided a significant survival-advantage over surgical monotherapy for AC (P=0.004), SCC (P=0.01). There was a 54% relative risk-reduction in lymph-node metastasis following MMT, compared with surgery (64% versus 29%, P<0.001). MMT produced a pathologic complete response (pCR) in 25% and 31% of AC and SCC, respectively. Survival advantage accrued to MMT, pCR and node-negative patients: AC pCR versus surgical monotherapy (P=0.001); residual disease following MMT versus surgical monotherapy (P=0.008); SCC pCR versus surgical monotherapy (P=0.033). A survival advantage for MMT persisted long-term in AC and was replicated in SCC. MMT produced loco-regional tumour down-staging to extinction in 25-31% of patients, potentially permitting personalised treatment in this cohort that avoids the morbidity and mortality associated with resection. Node-negative patients with residual localised disease following MMT had a survival advantage over node-negative patients following surgery alone, supporting a systemic effect on micro-metastatic disease. Copyright © 2014 Elsevier Ltd. All rights reserved.

Influence of oxygenation on chromium redox reactions with manganese sulfide (MnS(s)).

PubMed

Wadhawan, Amar R; Livi, Kenneth J; Stone, Alan T; Bouwer, Edward J

2015-03-17

Manganese sulfide (MnS(s)) minerals exist in sulfidic environments and can have unique reactive abilities because of sulfide, which is a known reductant, and Mn, the oxyhydroxides of which are known oxidants. This study elucidated the role of MnS(s) in controlling Cr speciation with implications on its fate and toxicity in the natural environment, specifically sulfidic sediments that undergo biogeochemical changes due to sediment resuspension during dredging, bioturbation, and flood events. In continuously mixed batch reaction experiments, aqueous CrVI reduction under anaerobic conditions occurred primarily on the surface of MnS(s) displaying a biphasic behavior- the initial rapid removal of CrVI from solution was followed by a slow decline due to surface passivation by reaction products, mainly sorbed or precipitated CrIII. The reaction progress increased with MnS(s) surface area loading but decreased on increasing CrVI concentration and pH, suggesting that surface site regeneration through product desorption was the rate-controlling mechanism. Below circum-neutral pH, higher solubility of MnS(s) resulted in additional CrVI reduction by reduced sulfur species in solution, whereas increased CrIII solubility lowered surface passivation allowing for more reactive sites to participate in the reaction. Aeration of MnS(s) at pH≥7 caused the formation of a heterogeneous MnIII(hydr)oxide that was composed of hausmanite and manganite. CrVI reoccurrence was observed on aeration of CrVI-spiked MnS(s) from the oxidation of product CrIII. The reoccurrence at pH≥7 was attributed to the oxidation of product CrIII by MnIII(hydr)oxide, whereas the reoccurrence at pH<7 was hypothesized from the oxidation of product CrIII by intermediate aqueous MnIII and/or sulfur species. Just as with Cr, MnS(s) may play an important role in speciation, fate, and transport of other environmental contaminants.

Giant-pulse Nd:YVO4 microchip laser with MW-level peak power by emission cross-sectional control.

PubMed

Kausas, Arvydas; Taira, Takunori

2016-02-22

We present a giant-pulse generation laser realized by the emission cross-section control of a gain medium in a passively Q-switched Nd:YVO4 microchip laser with a Cr4+:YAG saturable absorber. Up to 1.17 MW peak power and 1.03 mJ pulse energy were obtained with a 100 Hz repetition rate. By combining the Nd:YVO4 crystal with a Sapphire plate, lower temperature difference between a pump region in the gain crystal and a crystal holder was obtained which helped to keep the cavity in stability zone at elevated temperatures and allowed the achievement of the high peak power for this laser system.

Replication of CLU, CR1, and PICALM associations with alzheimer disease.

PubMed

Carrasquillo, Minerva M; Belbin, Olivia; Hunter, Talisha A; Ma, Li; Bisceglio, Gina D; Zou, Fanggeng; Crook, Julia E; Pankratz, V Shane; Dickson, Dennis W; Graff-Radford, Neill R; Petersen, Ronald C; Morgan, Kevin; Younkin, Steven G

2010-08-01

To test for replication of the association between variants in the CLU, CR1, and PICALM genes with Alzheimer disease. Follow-up case-control association study. The Mayo Clinics at Jacksonville, Florida, and Rochester, Minnesota. Community-based patients of European descent with late-onset Alzheimer disease (LOAD) and controls without dementia who were seen at the Mayo clinics, and autopsy-confirmed cases and controls whose pathology was evaluated at the Mayo Clinic in Jacksonville. Additional samples were obtained from the National Cell Repository for Alzheimer Disease (NCRAD). A total of 1829 LOAD cases and 2576 controls were analyzed. The most significant single-nucleotide polymorphisms in CLU (rs11136000), CR1 (rs3818361), and PICALM (rs3851179) were tested for allelic association with LOAD. Main Outcome Measure Clinical or pathology-confirmed diagnosis of LOAD. Odds ratios for CLU, CR1, and PICALM were 0.82, 1.15, and 0.80, respectively, comparable in direction and magnitude with those originally reported. P values were 8.6 x 10(-5), .014, and 1.3 x 10(-5), respectively; they remain significant even after Bonferroni correction for the 3 single-nucleotide polymorphisms tested. These results show near-perfect replication and provide the first additional evidence that CLU, CR1, and PICALM are associated with the risk of LOAD.

Exposure of pregnant mice to chromium picolinate results in skeletal defects in their offspring.

PubMed

Bailey, M M; Boohaker, J G; Sawyer, R D; Behling, J E; Rasco, J F; Jernigan, J J; Hood, R D; Vincent, J B

2006-06-01

Chromium(III) picolinate, [Cr(pic)(3)], is a widely marketed dietary supplement. However, Cr(pic)(3) has been associated with oxidative damage to DNA in rats and mutations and DNA fragmentation in cell cultures. In isolated case reports, Cr(pic)(3) supplementation has been said to cause adverse effects, such as anemia, renal failure, liver dysfunction, and neuronal impairment. To date, no studies have been published regarding the safety of chromium picolinate supplementation to a developing fetus, although Cr(pic)(3) has been recommended for pregnant women who are diagnosed with gestational diabetes. From gestation days (GD) 6-17, pregnant CD-1 mice were fed diets containing either 200 mg/kg Cr(pic)(3), 200 mg/kg CrCl(3), 174 mg/kg picolinic acid, or the diet only to determine if Cr(pic)(3), CrCl(3), or picolinic acid could cause developmental toxicity. Dams were sacrificed on GD 17, and their litters were examined for adverse effects. The incidence of bifurcated cervical arches was significantly increased in fetuses from the Cr(pic)(3) group as compared to the diet-only group. Fetuses in the picolinic acid-treated group had an incidence double that of the control group; however, this increase was not statistically significant. Fetuses in the CrCl(3) group did not differ from the controls in any variable examined. No maternal toxicity was observed in any of the treatment groups. High maternal oral exposures to chromium picolinate can cause morphological defects in developing offspring of mice.

Configuration of automatic exposure control on mammography units for computed radiography to match patient dose of screen film systems

NASA Astrophysics Data System (ADS)

Yang, Chang-Ying Joseph; Huang, Weidong

2009-02-01

Computed radiography (CR) is considered a drop-in addition or replacement for traditional screen-film (SF) systems in digital mammography. Unlike other technologies, CR has the advantage of being compatible with existing mammography units. One of the challenges, however, is to properly configure the automatic exposure control (AEC) on existing mammography units for CR use. Unlike analogue systems, the capture and display of digital CR images is decoupled. The function of AEC is changed from ensuring proper and consistent optical density of the captured image on film to balancing image quality with patient dose needed for CR. One of the preferences when acquiring CR images under AEC is to use the same patient dose as SF systems. The challenge is whether the existing AEC design and calibration process-most of them proprietary from the X-ray systems manufacturers and tailored specifically for SF response properties-can be adapted for CR cassettes, in order to compensate for their response and attenuation differences. This paper describes the methods for configuring the AEC of three different mammography units models to match the patient dose used for CR with those that are used for a KODAK MIN-R 2000 SF System. Based on phantom test results, these methods provide the dose level under AEC for the CR systems to match with the dose of SF systems. These methods can be used in clinical environments that require the acquisition of CR images under AEC at the same dose levels as those used for SF systems.

The cytotoxicity and genotoxicity of particulate and soluble hexavalent chromium in leatherback sea turtle lung cells.

PubMed

Speer, Rachel M; Wise, Catherine F; Young, Jamie L; Aboueissa, AbouEl-Makarim; Martin Bras, Mark; Barandiaran, Mike; Bermúdez, Erick; Márquez-D'Acunti, Lirio; Wise, John Pierce

2018-05-01

Hexavalent chromium [Cr(VI)] is a marine pollution of concern as recent studies show it has a global distribution, with some regions showing high Cr concentrations in marine animal tissue, and it is extensively used. Leatherback sea turtles (Dermochelys coriacea) are an endangered marine species that may experience prolonged exposures to environmental contaminants including Cr(VI). Human activities have led to global Cr(VI) contamination of the marine environment. While Cr(VI) has been identified as a known human carcinogen, the health effects in marine species are poorly understood. In this study, we assessed the cytotoxic and genotoxic effects of particulate and soluble Cr(VI) in leatherback sea turtle lung cells. Both particulate and soluble Cr(VI) induced a concentration-dependent increase in cytotoxicity. Next, using a chromosome aberration assay, we assessed the genotoxic effects of Cr(VI) in leatherback sea turtle lung cells. Particulate and soluble Cr(VI) induced a concentration-dependent increase in clastogenicity in leatherback sea turtle lung cells. These data indicate that Cr(VI) may be a health concern for leatherback sea turtles and other long-lived marine species. Additionally, these data provide foundational support to use leatherback sea turtles as a valuable model species for monitoring the health effects of Cr(VI) in the environment and possibly as an indicator species to assess environmental human exposures and effects. Copyright © 2018 Elsevier B.V. All rights reserved.

Etude de la Production de Paires de Leptons dans les Interactions Proton-Beryllium a 450 GEV

NASA Astrophysics Data System (ADS)

Aubry, Pierre Rene Roger

L'experience HELIOS a fait une etude precise de la production des paires e^+e^-, mu^+mu^-, mu ^+mu^-+nu, et mu^+/- e^+/- dans les interactions p-Be a 450 GeV. Le detecteur comporte un spectrometre a electrons, un spectrometre a muons, et un ensemble de calorimetres qui peuvent mesurer les photons et l'energie manquante emportee par les neutrinos. Les paires de leptons sont observees dans la region cinematique ^1: eqalign {2/m_mu 6 GeV cr E_{e}&>2.8 GeV cr.25&

Brief Report: Geographical Variation in Prevalence of Cryptococcal Antigenemia Among HIV-Infected, Treatment-Naive Patients in Nigeria: A Multicenter Cross-Sectional Study.

PubMed

Ezeanolue, Echezona E; Nwizu, Chidi; Greene, Gregory S; Amusu, Olatilewa; Chukwuka, Chinwe; Ndembi, Nicaise; Smith, Rachel M; Chiller, Tom; Pharr, Jennifer; Kozel, Thomas R

2016-09-01

Worldwide, HIV-associated cryptococcal meningitis affects approximately 1 million persons and causes 600,000 deaths each year mostly in sub-Saharan Africa. Limited data exist on cryptococcal meningitis and antigenemia in Nigeria, and most studies are geographically restricted. We determined the prevalence of cryptococcal antigenemia (CrAg) among HIV-infected, treatment-naive individuals in Nigeria. This was a retrospective, cross-sectional study across 4 geographic regions in Nigeria. We performed CrAg testing using a lateral flow immunoassay on archived whole-blood samples collected from HIV-infected participants at US President's Emergency Plan for AIDS Relief (PEPFAR)-supported sites selected to represent the major geographical and ethnic diversity in Nigeria. Eligible samples were collected from consenting patients (>15 years) naive to antiretroviral therapy with CD4 count less than 200 cells per cubic millimeter and were stored in an -80°C freezer. A total of 2752 stored blood samples were retrospectively screened for CrAg. Most of the samples were from participants aged 30-44 years (57.6%), and 1570 (57.1%) were from women. The prevalence of CrAg positivity in specimens with CD4 <200 cells per cubic millimeter was 2.3% (95% confidence interval: 1.8% to 3.0%) and varied significantly across the 4 regions (P < 0.001). At 4.4% (3.2% to 5.9%), the South East contained the highest prevalence. The significant regional variation in CrAg prevalence found in Nigeria should be taken into consideration as plans are made to integrate routine screening into clinical care for HIV-infected patients.

Geographical Variation in Prevalence of Cryptococcal Antigenemia among HIV-infected Treatment-Naïve Patients in Nigeria: A multicenter cross-sectional study

PubMed Central

Ezeanolue, Echezona E.; Nwizu, Chidi; Greene, Gregory S.; Amusu, Olatilewa; Chukwuka, Chinwe; Ndembi, Nicaise; Smith, Rachel M.; Chiller, Tom; Pharr, Jennifer; Kozel, Thomas R

2016-01-01

Objective Worldwide, HIV-associated cryptococcal meningitis affects approximately 1 million persons and causes 600,000 deaths each year mostly in sub-Sharan Africa. Limited data exist on cryptococcal meningitis and antigenemia in Nigeria, and most studies are geographically restricted. We determined the prevalence of cryptococcal antigenemia (CrAg) among HIV-infected treatment-naïve individuals in Nigeria. Design/Methods This was a retrospective, cross-sectional study across four geographic regions in Nigeria. We performed CrAg testing using a lateral flow immunoassay on archived whole blood samples collected from HIV-infected participants at US PEPFAR-supported sites selected to represent the major geographical and ethnic diversity in Nigeria. Eligible samples were (1) stored in an -80° freezer; (2) collected from consenting patients (>15 years) naïve to antiretroviral therapy with CD4+ count less than 200 cells/mm3. Results A total of 2,752 stored blood samples were retrospectively screened for CrAg. A majority of samples were from participants aged 30 - 44 (57.6%), and 1,570 (57.1%) were from women. The prevalence of CrAg positivity in specimens with CD4 < 200 cells/mm3 was 2.3% (95% CI = 1.8%-3.0%), and varied significantly across the four regions (p < 0.001). At 4.4% (3.2%-5.9%), the South East contained the highest prevalence. Conclusion The significant regional variation in CrAg prevalence found in Nigeria should be taken into consideration as plans are made to integrate routine screening into clinical care for HIV-infected patients. PMID:27144527

Genetic variations in two seahorse species (Hippocampus mohnikei and Hippocampus trimaculatus): evidence for middle Pleistocene population expansion.

PubMed

Zhang, Yanhong; Pham, Nancy Kim; Zhang, Huixian; Lin, Junda; Lin, Qiang

2014-01-01

Population genetic of seahorses is confidently influenced by their species-specific ecological requirements and life-history traits. In the present study, partial sequences of mitochondrial cytochrome b (cytb) and control region (CR) were obtained from 50 Hippocampus mohnikei and 92 H. trimaculatus from four zoogeographical zones. A total of 780 base pairs of cytb gene were sequenced to characterize mitochondrial DNA (mtDNA) diversity. The mtDNA marker revealed high haplotype diversity, low nucleotide diversity, and a lack of population structure across both populations of H. mohnikei and H. trimaculatus. A neighbour-joining (NJ) tree of cytb gene sequences showed that H. mohnikei haplotypes formed one cluster. A maximum likelihood (ML) tree of cytb gene sequences showed that H. trimaculatus belonged to one lineage. The star-like pattern median-joining network of cytb and CR markers indicated a previous demographic expansion of H. mohnikei and H. trimaculatus. The cytb and CR data sets exhibited a unimodal mismatch distribution, which may have resulted from population expansion. Mismatch analysis suggested that the expansion was initiated about 276,000 years ago for H. mohnikei and about 230,000 years ago for H. trimaculatus during the middle Pleistocene period. This study indicates a possible signature of genetic variation and population expansion in two seahorses under complex marine environments.

Phytoremediation for co-contaminated soils of chromium and benzo[a]pyrene using Zea mays L.

PubMed

Chigbo, Chibuike; Batty, Lesley

2014-02-01

A greenhouse experiment was carried out to investigate the single effect of benzo[a]pyrene (B[a]P) or chromium (Cr) and the joint effect of Cr-B[a]P on the growth of Zea mays, its uptake and accumulation of Cr, and the dissipation of B[a]P over 60 days. Results showed that single or joint contamination of Cr and B[a]P did not affect the plant growth relative to control treatments. However, the occurrence of B[a]P had an enhancing effect on the accumulation and translocation of Cr. The accumulation of Cr in shoot of plant significantly increased by ≥ 79 % in 50 mg kg(-1) Cr-B[a]P (1, 5, and 10 mg kg(-1)) treatments and by ≥ 86 % in 100 mg kg(-1) Cr-B[a]P (1, 5, and 10 mg kg(-1)) treatments relative to control treatments. The presence of plants did not enhance the dissipation of B[a]P in lower (1and 5 mg kg(-1)) B[a]P contaminated soils; however, over 60 days of planting Z. mays seemed to enhance the dissipation of B[a]P by over 60 % in 10 mg kg(-1) single contaminated soil and by 28 to 41 % in 10 mg kg(-1)B[a]P co-contaminated soil. This suggests that Z. mays might be a useful plant for the remediation of Cr-B[a]P co-contaminated soil.

Adaboost multi-view face detection based on YCgCr skin color model

NASA Astrophysics Data System (ADS)

Lan, Qi; Xu, Zhiyong

2016-09-01

Traditional Adaboost face detection algorithm uses Haar-like features training face classifiers, whose detection error rate is low in the face region. While under the complex background, the classifiers will make wrong detection easily to the background regions with the similar faces gray level distribution, which leads to the error detection rate of traditional Adaboost algorithm is high. As one of the most important features of a face, skin in YCgCr color space has good clustering. We can fast exclude the non-face areas through the skin color model. Therefore, combining with the advantages of the Adaboost algorithm and skin color detection algorithm, this paper proposes Adaboost face detection algorithm method that bases on YCgCr skin color model. Experiments show that, compared with traditional algorithm, the method we proposed has improved significantly in the detection accuracy and errors.

Effect of chromium on bioenergetics and leukocyte dynamics following immunoactivation in lactating Holstein cows.

PubMed

Horst, E A; Kvidera, S K; Mayorga, E J; Shouse, C S; Al-Qaisi, M; Dickson, M J; Ydstie, J; Ramirez Ramirez, H A; Keating, A F; Dickson, D J; Griswold, K E; Baumgard, L H

2018-06-01

Activated immune cells are insulin sensitive and utilize copious amounts of glucose. Because chromium (Cr) increases insulin sensitivity and may be immunomodulatory, our objective was to evaluate the effect of supplemental Cr (KemTrace Cr propionate, 20 g/d; Kemin Industries Inc., Des Moines, IA) on immune system glucose utilization and immune system dynamics following an intravenous endotoxin challenge in lactating Holstein cows. Twenty cows (320 ± 18 d in milk) were randomly assigned to 1 of 4 treatments: (1) pair-fed (PF) control (PF-CON; 5 mL of saline; n = 5), (2) PF and Cr supplemented (PF-Cr; 5 mL of saline; n = 5), (3) lipopolysaccharide (LPS)-euglycemic clamp and control supplemented (LPS-CON; 0.375 µg/kg of body weight LPS; n = 5), and (4) LPS-euglycemic clamp and Cr supplemented (LPS-Cr; 0.375 µg/kg of body weight LPS; n = 5). The experiment was conducted serially in 3 periods (P). During P1 (3 d), cows received their respective dietary treatments and baseline values were obtained. At the initiation of P2 (2 d), either a 12-h LPS-euglycemic clamp was conducted or cows were PF to their respective dietary counterparts. During P3 (3 d), cows consumed feed ad libitum and continued to receive their respective dietary treatment. During P2, LPS administration decreased dry matter intake (DMI; 40%) similarly among diets, and by experimental design the pattern and magnitude of reduced DMI were similar in the PF cohorts. During P3, LPS-Cr cows tended to have decreased DMI (6%) relative to LPS-CON cows. Relative to controls, milk yield from LPS-challenged cows decreased (58%) during P2 and LPS-Cr cows produced less (16%) milk than LPS-CON cows. During P3, milk yield progressively increased similarly in LPS-administered cows, but overall milk yield remained decreased (24%) compared with PF controls. There were no dietary treatment differences in milk yield during P3. Circulating insulin increased 9- and 15-fold in LPS-administered cows at 6 and 12 h postbolus, respectively, compared with PF controls. Compared with LPS-CON cows, circulating insulin in LPS-Cr cows was decreased (48%) at 6 h postbolus. Relative to PF cows, circulating LPS binding protein and serum amyloid A from LPS-administered cows increased 2- and 5-fold, respectively. Compared with PF cows, blood neutrophil counts in LPS-infused cows initially decreased, then gradually increased 163%. Between 18 and 48 h postbolus, the number of neutrophils was increased (12%) in LPS-Cr versus LPS-CON cows. The 12-h total glucose deficit was 220 and 1,777 g for the PF and LPS treatments, respectively, but glucose utilization following immune activation was not influenced by Cr. In summary, supplemental Cr reduced the insulin response and increased circulating neutrophils following an LPS challenge but did not appear to alter the immune system's glucose requirement following acute and intense activation. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Kinetics and modeling of hexavalent chromium reduction in Enterobacter cloacae

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yamamoto, Koji; Kato, Junichi; Yano, Takuo

1993-01-05

Kinetics of bacterial reduction of toxic hexavalent chromium (chromate: CrO[sub 4][sup [minus]2]) was investigated using batch and fed-batch cultures of Enterobacter cloacae strain HO1. In fed-batch cultures, the CrO[sub 4][sup [minus]2] feed was controlled on the basis of the rate of pH change. This control strategy has proven to be useful for avoiding toxic CrO[sub 3][sup [minus]2] overload. A simple mathematical model was developed to describe the bacterial process of CrO[sub 4][sup [minus]2] reduction. In this model, two types of bacterial cells were considered: induced, CrO[sub 4][sup [minus]2]-resistant cells and uninduced, sensitive ones. Only resistant cells were assumed to bemore » able to reduce CrO[sub 4][sup [minus]2]. These fundamental ideas were supported by the model predictions which well approximated all experimental data. In a simulation study, the model was also used to optimize fed-batch cultures, instead of lengthy and expensive laboratory experiments.« less

A Proton Magnetic Resonance Spectroscopic Study in Autism Spectrum Disorder Using a 3-Tesla Clinical Magnetic Resonance Imaging (MRI) System: The Anterior Cingulate Cortex and the Left Cerebellum.

PubMed

Ito, Hiromichi; Mori, Kenji; Harada, Masafumi; Hisaoka, Sonoka; Toda, Yoshihiro; Mori, Tatsuo; Goji, Aya; Abe, Yoko; Miyazaki, Masahito; Kagami, Shoji

2017-07-01

The pathophysiology of autism spectrum disorder (ASD) is not fully understood. We used proton magnetic resonance spectroscopy to investigate metabolite concentration ratios in the anterior cingulate cortex and left cerebellum in ASD. In the ACC and left cerebellum studies, the ASD group and intelligence quotient- and age-matched control group consisted of 112 and 114 subjects and 65 and 45 subjects, respectively. In the ASD group, γ-aminobutyric acid (GABA)+/ creatine/phosphocreatine (Cr) was significantly decreased in the anterior cingulate cortex, and glutamate (Glu)/Cr was significantly increased and GABA+/Cr was significantly decreased in the left cerebellum compared to those in the control group. In addition, both groups showed negative correlations between Glu/Cr and GABA+/Cr in the left cerebellum, and positive correlations between GABA+/Cr in the anterior cingulate cortex and left cerebellum. ASD subjects have hypoGABAergic alterations in the anterior cingulate cortex and hyperglutamatergic/hypoGABAergic alterations in the left cerebellum.

Effect of Ginseng on Calretinin Expression in Mouse Hippocampus Following Exposure to 835 MHz Radiofrequency

PubMed Central

Aryal, Bijay; Maskey, Dhiraj; Kim, Myeung-Ju; Yang, Jae-Won; Kim, Hyung-Gun

2011-01-01

Exponential rise in the use of mobile communication devices has generated health concerns due to radiofrequency (RF) exposure due to its close proximity to the head. Calcium binding proteins like calretinin regulate the levels of calcium (Ca2+) which plays an important role in biological systems. Ginseng is known for maintaining equilibrium in the human body and may play a beneficial radioprotectant role against electromagnetic field (EMF) exposure. In the present study, we evaluated the radioprotective effects of red ginseng (RG) extract in a mouse model. Calretinin (CR) expression was measured using a free-floating immunohistochemical method in the hippocampus of mice after 835 MHz EMF exposure for 5 h/d for 5 d at specific absorption rate=1.6 W/kg for the different experimental groups. The control animals were treated with NaCl while the experimental animals received 10 mg/kg ginseng, or 30 mg/kg; EMF exposed mice were also treated with NaCl, 10 mg/kg ginseng (E10), or 30 mg/kg (E30). Decreases in CR immunoreactivity (IR) along with loss of CA1 and CA3 interneurons and infragranular cells were observed in the ENaCl group while such losses were not observed in the E10 and E30 groups. CR IR significantly increased in the RG-treated group compared to control and EMF-exposed groups treated with NaCl. The study demonstrates that RG extract can serve as a radioprotective agent that maintains Ca2+ homeostasis and prevents neuronal loss in the brain hippocampal region caused by RF exposure. PMID:23717055

Chromium Exposure and Risk of Cardiovascular Disease in High Cardiovascular Risk Subjects　- Nested Case-Control Study in the Prevention With Mediterranean Diet (PREDIMED) Study.

PubMed

Gutiérrez-Bedmar, Mario; Martínez-González, Miguel Ángel; Muñoz-Bravo, Carlos; Ruiz-Canela, Miguel; Mariscal, Alberto; Salas-Salvadó, Jordi; Estruch, Ramón; Corella, Dolores; Arós, Fernando; Fito, Monserrat; Lapetra, José; Serra-Majem, Lluís; Pintó, Xavier; Alonso-Gómez, Ángel; Portoles, Olga; Fiol, Miquel; Bulló, Mónica; Castañer, Olga; Ros, Emilio; Gómez-Gracia, Enrique

2017-07-25

Epidemiological data on chromium (Cr) exposure and the risk of cardiovascular disease (CVD) are still limited. Toenail Cr level (TCL) provides a time-integrated measure reflecting long-term Cr exposure. We measured TCL to assess the hypothesis that long-term Cr exposure was inversely associated with incident CVD in a population at high risk for CVD.Methods and Results:The associations between TCL and CVD were evaluated in a case-control study nested within the "PREvención con DIeta MEDiterránea" (PREDIMED) trial. We randomly selected 147 of the 288 patients diagnosed with CVD during follow-up and matched them on age and sex to 271 controls. Instrumental neutron activation analysis was used to assess TCL. In-person interviews, medical record reviews, and validated questionnaires were used to assess covariates. The fully adjusted OR for the highest vs. lowest quartile of toenail Cr was 0.54 (95% CI: 0.26-1.14; P trend =0.189) for the nested case-control study. On stratification for diabetes mellitus (DM), OR was 1.37 (95% CI: 0.54-3.46; P trend =0.364) for the DM group, and 0.25 (95% CI: 0.08-0.80; P trend =0.030) for the non-DM group (P for interaction=0.078). The present findings, although not statistically significant, are consistent with previously reported inverse associations between TCL and CVD. These results, especially for non-DM patients, increase the limited epidemiological knowledge about the possible protective role of Cr against CVD. (Trial registration: www.controlled-trials.com; ISRCTN35739639.).

Incineration of tannery sludge under oxic and anoxic conditions: study of chromium speciation.

PubMed

Kavouras, P; Pantazopoulou, E; Varitis, S; Vourlias, G; Chrissafis, K; Dimitrakopulos, G P; Mitrakas, M; Zouboulis, A I; Karakostas, Th; Xenidis, A

2015-01-01

A tannery sludge, produced from physico-chemical treatment of tannery wastewaters, was incinerated without any pre-treatment process under oxic and anoxic conditions, by controlling the abundance of oxygen. Incineration in oxic conditions was performed at the temperature range from 300°C to 1200°C for duration of 2h, while in anoxic conditions at the temperature range from 400°C to 600°C and varying durations. Incineration under oxic conditions at 500°C resulted in almost total oxidation of Cr(III) to Cr(VI), with CaCrO4 to be the crystalline phase containing Cr(VI). At higher temperatures a part of Cr(VI) was reduced, mainly due to the formation of MgCr2O4. At 1200°C approximately 30% of Cr(VI) was reduced to Cr(III). Incineration under anoxic conditions substantially reduced the extent of oxidation of Cr(III) to Cr(VI). Increase of temperature and duration of incineration lead to increase of Cr(VI) content, while no chromium containing crystalline phase was detected. Copyright © 2014 Elsevier B.V. All rights reserved.

Assessing the potential ecological risk of Co, Cr, Cu, Fe and Zn in the sediments of Hooghly-Matla estuarine system, India.

PubMed

Ghosh, Somdeep; Bakshi, Madhurima; Kumar, Alok; Ramanathan, A L; Biswas, Jayanta Kumar; Bhattacharyya, Subarna; Chaudhuri, Punarbasu; Shaheen, Sabry M; Rinklebe, Jörg

2018-05-09

Hooghly-Matla estuarine system along with the Sundarbans mangroves forms one of the most diverse and vulnerable ecosystems in the world. We have investigated the distribution of Co, Cr, Cu, Fe and Zn along with sediment properties at six locations [Shamshernagar (S1), Kumirmari (S2 and S3), Petuaghat (S4), Tapoban (S5) and Chemaguri (S6)] in the Hooghly estuary and reclaimed islands of the Sundarbans for assessing the degree of contamination and potential ecological risks. Enrichment factor values (0.9-21.6) show enrichment of Co, Cu and Zn in the intertidal sediments considering all sampling locations and depth profiles. Geo-accumulation index values irrespective of sampling locations and depth revealed that Co and Cu are under class II and class III level indicating a moderate contamination of sediments. The pollution load index was higher than unity (1.6-2.1), and Co and Cu were the major contributors to the sediment pollution followed by Zn, Cr and Fe with the minimum values at S1 and the maximum values at S5. The sediments of the Hooghly-Matla estuarine region (S4, S5 and S6) showed considerable ecological risks, when compared with effect range low/effect range median and threshold effect level/probable effect level values. The variation in the distribution of the studied elements may be due to variation in discharge pattern and exposure to industrial effluent and domestic sewage, storm water and agricultural run-off and fluvial dynamics of the region. The study illuminates the necessity for the proper management of vulnerable coastal estuarine ecosystem by stringent pollution control measures along with regular monitoring and checking program.

Molecular Analysis of Ciprofloxacin Resistance Mechanisms in Malaysian ESBL-Producing Klebsiella pneumoniae Isolates and Development of Mismatch Amplification Mutation Assays (MAMA) for Rapid Detection of gyrA and parC Mutations

PubMed Central

Mohd Yusof, Mohd Yasim; Tay, Sun Tee

2014-01-01

Ninety-three Malaysian extended-spectrum β-lactamase (ESBL)-producing Klebsiella pneumoniae isolates were investigated for ciprofloxacin resistance. Two mismatch amplification mutation (MAMA) assays were developed and used to facilitate rapid detection of gyrA and parC mutations. The isolates were also screened for plasmid-mediated quinolone resistance (PMQR) genes including aac(6′)-Ib-cr, qepA, and qnr. Ciprofloxacin resistance (MICs 4– ≥ 32 μg/mL) was noted in 34 (37%) isolates, of which 33 isolates had multiple mutations either in gyrA alone (n = 1) or in both gyrA and parC regions (n = 32). aac(6′)-Ib-cr was the most common PMQR gene detected in this study (n = 61), followed by qnrB and qnrS (n = 55 and 1, resp.). Low-level ciprofloxacin resistance (MICs 1-2 μg/mL) was noted in 40 (43%) isolates carrying qnrB accompanied by either aac(6′)-Ib-cr (n = 34) or a single gyrA 83 mutation (n = 6). Ciprofloxacin resistance was significantly associated with the presence of multiple mutations in gyrA and parC regions. While the isolates harbouring gyrA and/or parC alteration were distributed into 11 PFGE clusters, no specific clusters were associated with isolates carrying PMQR genes. The high prevalence of ciprofloxacin resistance amongst the Malaysian ESBL-producing K. pneumoniae isolates suggests the need for more effective infection control measures to limit the spread of these resistant organisms in the hospital. PMID:24860827

Creep and Toughness of Cryomilled NiAl Containing Cr

NASA Technical Reports Server (NTRS)

Whittenberger, J. Daniel; Aikin, Beverly; Salem, Jon

2000-01-01

NiAl-AlN + Cr composites were produced by blending cryomilled NiAl powder with approx. 10 vol % Cr flakes. In comparison to the as-consolidated matrices, hot isostatically pressed Cr-modified materials did not demonstrate any significant improvement in toughness. Hot extruded NiAl-AlN+10.5Cr, however, possessed a toughness twice that determine for the base NiAl-AlN alloy. Measurement of the 1200 to 1400 K plastic flow properties revealed that the strength of the composites was completely controlled by the properties of the NiAl-AlN matrices. This behavior could be successfully modeled by the Rule-of-Mixtures, where load is shed from the weak Cr to the strong matrix.

Polymer-Based Materials of Controlled Permeability and Application of Photoinduced Magnetism

DTIC Science & Technology

2010-07-31

Decrease in the FC magnetization upon excitation with UV light for K1:54VII0:77VIII 0:08[ CrIII (CN)6](SO4)0:16_3.1 H2O (1) dispersed in Nujol oil. Inset...magnetization upon excitation with UV light for K1:54VII0:77VIII 0:08[ CrIII (CN)6](SO4)0:16_3.1 H2O (1) dispersed in Nujol oil. Inset: UV-Vis spectrum of 1...Nelson, M.C. Daniels, W.M. Reiff, S.A. Troff, J.S. Miller, [ CrIII (NCMe)6]3+ - A Labile CrIII Source Enabling Formation of Cr[M(CN)6] (M = V, Cr, Mn, Fe

Whole-body low-dose computed tomography in multiple myeloma staging: Superior diagnostic performance in the detection of bone lesions, vertebral compression fractures, rib fractures and extraskeletal findings compared to radiography with similar radiation exposure.

PubMed

Lambert, Lukas; Ourednicek, Petr; Meckova, Zuzana; Gavelli, Giampaolo; Straub, Jan; Spicka, Ivan

2017-04-01

The primary objective of the present prospective study was to compare the diagnostic performance of conventional radiography (CR) and whole-body low-dose computed tomography (WBLDCT) with a comparable radiation dose reconstructed using hybrid iterative reconstruction technique, in terms of the detection of bone lesions, skeletal fractures, vertebral compressions and extraskeletal findings. The secondary objective was to evaluate lesion attenuation in relation to its size. A total of 74 patients underwent same-day skeletal survey by CR and WBLDCT. In CR and WBLDCT, two readers assessed the number of osteolytic lesions at each region and stage according to the International Myeloma Working Group (IMWG) criteria. A single reader additionally assessed extraskeletal findings and their significance, the number of vertebral compressions and bone fractures. The radiation exposure was 2.7±0.9 mSv for WBLDCT and 2.5±0.9 mSv for CR (P=0.054). CR detected bone involvement in 127 out of 486 regions (26%; P<0.0001), confirmed by WBLDCT. CR underestimated the disease stage in 16% and overestimated it in 8% of the patients (P=0.0077). WBLDCT detected more rib fractures compared with CR (188 vs. 47; P<0.0001), vertebral compressions (93 vs. 67; P=0.010) and extraskeletal findings (194 vs. 52; P<0.0001). There was no correlation observed between lesion size (≥5 mm) and its attenuation (r=-0.006; P=0.93). The inter-observer agreement for the presence of osteolytic lesions was κ=0.76 for WBLDCT, and κ=0.55 for CR. The present study concluded that WBLDCT with hybrid iterative reconstruction technique demonstrates superiority to CR with an identical radiation dose in the detection of bone lesions, skeletal fractures, vertebral compressions and extraskeletal findings, which results in up- or downstaging in 24% patients according to the IMWG criteria. The attenuation of osteolytic lesions can be measured with the avoidance of the partial volume effect.

Exploration of the region near the sun-earth collinear libration points for the control of large formations

NASA Astrophysics Data System (ADS)

Heritier, Aurelie

Spacecraft formations possess many applications in the future of space exploration. During the last decade, due to the detection of a large number of extrasolar planets, new studies on formation flying in multi-body regimes have emerged to support searches for Earth-like planets in other solar systems. The L2 Sun-Earth libration point region has been a popular destination in creating an architecture for astronomical missions. It is a relatively cold environment, far from the disturbances of the Sun and, therefore, ideal for astronomical instruments. However, controlling multiple spacecraft in a multi-body environment is challenging and a good understanding of the natural dynamics in this regime is essential. The current investigation explores the dynamical environment near the L2 Sun-Earth libration point to aid in the control of formations of spacecraft. By exploiting the natural dynamics in the circular restricted three-body model (CR3BP), natural regions are determined that are particularly suitable for maintaining formations of spacecraft. The natural dynamics at small distances from a given reference trajectory are initially investigated for the placement of small formations of spacecraft. Some regions with low relative drift represent suitable locations to maintain small formations and are derived analytically using variational equations. Spacecraft located in such regions avoid large variations in their mutual distances while maintaining the orientation of the formation. These regions represent quadric surfaces, and the type of quadric surfaces, either ellipsoids or elliptic cylinders, depends on the eigenstructure reflecting the phase space along the given reference trajectory. The natural flow at large distances from a given reference trajectory is explored next to characterize regions that are suitable to maintain large formations, i.e., when the mutual distances between the spacecraft reaches tens of thousands of kilometers. Spheres of points at various locations along the reference orbit are constructed to classify the space, and regions of low natural drift on the spheres are numerically identified when the distance between two vehicles is large. These low drift regions are examined in detail, and a correspondance with the quadric surfaces that are derived for small formations is established. In particular, the orientation of these low drift zones along a given reference orbit are investigated as some parameters vary, such as the size of the formation as well as the reference orbit. Using the low natural drift regions, control strategies are then developed for large formations. Traditional controllers, such as impulsive maneuvers and linear quadratic regulators (LQR), are employed to quantify the level of control that is required to maintain large formations along specific directions in the CR3BP. Designs of new controllers are also investigated to produce some set of desired relative motions between two spacecraft placed at large mutual distances. In a potential formation option investigated in this analysis, a deputy vehicle maintains a fixed circular motion in a plane relative to a chief spacecraft moving along its reference trajectory. Finally, the effectiveness of using the low natural drift regions as derived for large formations is tested for the New Worlds Observer mission concept. This scenario involves a large telescope-occulter formation for star observations, to detect and characterize habitable terrestrial exoplanets. The low drift zones are employed to reduce the control effort to maintain a large telescope-occulter formation during the observation of inertially-fixed target stars. In particular, the occulter is maintained via a linear quadratic regulator during star observations. Given a set of inertially-fixed target stars, an automatic star sequence design process is proposed with observation and reconfiguration phases using the low drift regions. This design creates star sequences that lead to relatively small overall maneuver costs for this particular mission concept.

Solar activity beyond the disk and variations of the cosmic ray gradient

NASA Technical Reports Server (NTRS)

Belov, A. V.; Dorman, L. I.; Eroshenko, E. A.; Ishkov, V. N.; Oleneva, V. A.

1985-01-01

Part of galactic cosmic rays (CR) observed near the Earth and on the Earth come from beyond-disk regions of circumsolar space. But CR of those energies which undergo substantial modulation cover too large a path across the lines of force of the interplanetary magnetic field (IMF) in order that they could provide an effective transfer of information about beyond-disk solar activity. And if it is still possible, the most probable channel for transferring such information must be a neutral layer of heliomagnetosphere in which the transverse CR transport is facilitated by their drift in an inhomogeneous magnetic field. A simple diffusion model for an expected CR variation in a neutral layer near the Earth is discussed. It is of importance that variations of the CR gradient are not at all always accompanied by considerable variations of IMF and solar wind velocity at the point of observation.

Biochemical and single-molecule analyses of the RNA silencing suppressing activity of CrPV-1A

PubMed Central

Watanabe, Mariko; Iwakawa, Hiro-oki; Tadakuma, Hisashi

2017-01-01

Abstract Viruses often encode viral silencing suppressors (VSSs) to counteract the hosts’ RNA silencing activity. The cricket paralysis virus 1A protein (CrPV-1A) is a unique VSS that binds to a specific Argonaute protein (Ago)—the core of the RNA-induced silencing complex (RISC)—in insects to suppress its target cleavage reaction. However, the precise molecular mechanism of CrPV-1A action remains unclear. Here we utilized biochemical and single-molecule imaging approaches to analyze the effect of CrPV-1A during target recognition and cleavage by Drosophila Ago2-RISC. Our results suggest that CrPV-1A obstructs the initial target searching by Ago2-RISC via base pairing in the seed region. The combination of biochemistry and single-molecule imaging may help to pave the way for mechanistic understanding of VSSs with diverse functions. PMID:28977639

Status, methods and aims of the knee investigations at CR spectrum

NASA Astrophysics Data System (ADS)

Shaulov, S. B.; Bezshapov, S. P.

2013-02-01

Usually it is supposed that the definition of the CR mass composition in knee region is the key to problem of CR spectrum modification in this range. However tens of experiments done for the last half a century, have not decided this problem. The possible causes of fiasco and arguments in favour of necessity to reformulate a method of attack are discussed. It is formulated that the first experimental task now is to solve a more simple problem: is there abnormal CR component in knee field or not. It seams that impossible to formulate correctly more common problem of mass composition without solving of this one. The observational basis is discussed. The hypothesis of strange quark matter is suggested for the abnormal component.

Respiratory health effects of long-term exposure to different chromium species in stainless steel production.

PubMed

Huvinen, M; Uitti, J; Oksa, P; Palmroos, P; Laippala, P

2002-06-01

The aim of this study was to determine whether occupational exposure to chromite, trivalent chromium (Cr(3+)) or hexavalent chromium (Cr(6+)) causes respiratory diseases, an excess of respiratory symptoms, a decrease in pulmonary function or signs of pneumoconiosis among workers in stainless steel production. Altogether, 203 exposed workers and 81 referents with an average employment of 23 years were investigated for indicators of respiratory health on two occasions, in 1993 and in 1998. Data collection with a self-administered questionnaire, flow volume spirometry, measurement of diffusing capacity, chest radiography and laboratory tests were carried out by a mobile research unit. Exposure to different chromium species and other metals was monitored regularly and studied separately. No adverse respiratory health effects were observed in the group exposed to Cr(6+), either in comparison with the control group in the first cross-sectional study or during the additional 5 year follow-up. Among the Cr (3+) exposed people, the production of phlegm, shortness of breath and breathlessness on exertion were significantly more frequent than in the control group, but the frequency of the symptoms did not increase during the follow-up; no differences were observed in the lung function tests and the radiographic findings did not progress. In the chromite group, the prevalence of breathlessness on exertion was higher than in the control group. However, in the follow-up, the occurrence of symptoms did not differ from 1993 to 1998. In the first study, most parameters of lung function were lower among the smokers in the chromite group than among the smoking controls, but in 1998 the difference was less marked. An average exposure time of 23 years in modern ferrochromium and stainless steel production and low exposure to dusts and fumes containing Cr(6+), Cr(3+), nickel and molybdenum do not lead to respiratory changes detectable by lung function tests or radiography. The workers exposed to Cr(3+) had more respiratory symptoms than those in the control group. The workers in the chromite mine had lower lung function test results than the control group due to earlier exposure to higher dust concentrations.

Blood harmane is correlated with cerebellar metabolism in essential tremor: a pilot study.

PubMed

Louis, Elan D; Zheng, Wei; Mao, Xiangling; Shungu, Dikoma C

2007-08-07

On proton magnetic resonance spectroscopic imaging ((1)H MRSI), there is a decrease in cerebellar N-acetylaspartate/total creatine (NAA/tCr) in essential tremor (ET), signifying cerebellar neuronal dysfunction or degeneration. Harmane, which is present in the human diet, is a potent tremor-producing neurotoxin. Blood harmane concentrations seem to be elevated in ET. To assess in patients with ET whether blood harmane concentration is correlated with cerebellar NAA/tCR, a neuroimaging measure of neuronal dysfunction or degeneration. Twelve patients with ET underwent (1)H MRSI. The major neuroanatomic structure of interest was the cerebellar cortex. Secondary regions were the central cerebellar white matter, cerebellar vermis, thalamus, and basal ganglia. Blood concentrations of harmane and another neurotoxin, lead, were also assessed. Mean +/- SD cerebellar NAA/tCR was 1.52 +/- 0.41. In a linear regression model that adjusted for age and gender, log blood harmane concentration was a predictor of cerebellar NAA/tCR (beta = -0.41, p = 0.009); every 1 g(-10)/mL unit increase in log blood harmane concentration was associated with a 0.41 unit decrease in cerebellar NAA/tCR. The association between blood harmane concentration and brain NAA/tCR only occurred in the cerebellar cortex; it was not observed in secondary brain regions of interest. Furthermore, the association was specific to harmane and not another neurotoxin, lead. This study provides additional support for the emerging link between harmane, a neurotoxin, and ET. Further studies are warranted to address whether cerebellar harmane concentrations are associated with cerebellar pathology in postmortem studies of the ET brain.

Brain metabolites in autonomic regulatory insular sites in heart failure.

PubMed

Woo, Mary A; Yadav, Santosh K; Macey, Paul M; Fonarow, Gregg C; Harper, Ronald M; Kumar, Rajesh

2014-11-15

Autonomic, pain, and neuropsychologic comorbidities appear in heart failure (HF), likely resulting from brain changes, indicated as loss of structural integrity and functional deficits. Among affected brain sites, the anterior insulae are prominent in serving major regulatory roles in many of the disrupted functions commonly seen in HF. Metabolite levels, including N-acetylaspartate (NAA), creatine (Cr), choline (Cho), and myo-inositol (MI), could indicate the nature of anterior insula tissue injury in HF. The study aim was to assess anterior insular metabolites to determine processes mediating autonomic, pain, and neuropsychologic disruptions in HF. We performed magnetic resonance spectroscopy in bilateral anterior insulae in 11 HF and 53 controls, using a 3.0-Tesla magnetic resonance imaging scanner. Peaks for NAA at 2.02 ppm, Cr at 3.02 ppm, Cho at 3.2 ppm, and MI at 3.56 ppm were assigned, peak areas were calculated, and metabolites were expressed as ratios, including NAA/Cr, Cho/Cr, and MI/Cr. HF patients showed significantly increased Cho/Cr ratios, indicative of glial proliferation or injury, on the left anterior insula, and reduced NAA/Cr levels, suggesting neuronal loss/dysfunction, on the right anterior insula over controls. No differences in MI/Cr ratios appeared between groups. Right anterior insular neuronal loss and left glial alterations may contribute to distorted autonomic, pain, and neuropsychologic functions found in HF. Copyright © 2014 Elsevier B.V. All rights reserved.

Determination of chromium (VI) in primary and secondary fertilizer and their respective precursors.

PubMed

Krüger, Oliver; Fiedler, Francesca; Adam, Christian; Vogel, Christian; Senz, Rainer

2017-09-01

Hexavalent chromium species (Cr(VI)) are often carcinogenic, of high acute toxicity, highly mobile, and thus pose a severe risk to health and environment. Fertilizers usually contain significant amounts of chromium. Therefore, a reliable analysis of chromium and the fraction of Cr(VI) are crucial for safe use of fertilizers. This problem is expected to increase in the future, since more and more recycled fertilizers emerge due to increasing fertilizer demand and respective supply risks. However, existing analytical methods have been developed for conventional fertilizers and have to be tested whether they are suitable for the new materials. Thus, we performed a wet-chemical extraction for Cr(VI) on several matrices as well as respective quality control experiments including spiking with Cr(III) and Cr(VI) compounds. We found the Cr(VI) amounts to be below 2 mg/kg except for a thermally post-treated sewage sludge ash (SSA) that showed 12.3 mg/kg. The presence of organic matter e.g. in sludge or precipitated struvite caused a reduction of spiked Cr(VI) and thus no satisfying recovery for quality control. Cr(VI) reduction was also observed for SSA, presumably due to the presence of Fe(II) compounds. Even though the tested procedure can be hampered in some recycled fertilizer matrices, it might be adapted to be applicable also for these complex samples. Copyright © 2017 Elsevier Ltd. All rights reserved.

Brain Metabolites in Autonomic Regulatory Insular Sites in Heart Failure

PubMed Central

Woo, Mary A.; Yadav, Santosh K.; Macey, Paul M.; Fonarow, Gregg C.; Harper, Ronald M.; Kumar, Rajesh

2014-01-01

Autonomic, pain, and neuropsychologic comorbidities appear in heart failure (HF), likely resulting from brain changes, indicated as loss of structural integrity and functional deficits. Among affected brain sites, the anterior insulae are prominent in serving major regulatory roles in many of the disrupted functions commonly seen in HF. Metabolite levels, including N-acetylaspartate (NAA), creatine (Cr), choline (Cho), and myo-inositol (MI), could indicate the nature of anterior insula tissue injury in HF. The study aim was to assess anterior insular metabolites to determine processes mediating autonomic, pain, and neuropsychologic disruptions in HF. We performed magnetic resonance spectroscopy in bilateral anterior insulae in 11 HF and 53 controls, using a 3.0-Tesla magnetic resonance imaging scanner. Peaks for NAA at 2.02ppm, Cr at 3.02ppm, Cho at 3.2ppm, and MI at 3.56ppm were assigned, peak areas calculated, and metabolites expressed as ratios, including NAA/Cr, Cho/Cr, and MI/Cr. HF patients showed significantly increased Cho/Cr ratios, indicative of glial proliferation or injury, on the left anterior insula, and reduced NAA/Cr levels, suggesting neuronal loss/dysfunction, on the right anterior insula over controls. No differences in MI/Cr ratios appeared between groups. Right anterior insular neuronal loss and left glial alterations may contribute to distorted autonomic, pain, and neuropsychologic functions found in HF. PMID:25248953

[Study on distribution characteristics and potential ecological risk of soil heavy metals in the Yellow River beach region in Kaifeng City].

PubMed

Zhang, Peng-yan; Qin, Ming-zhou; Chen, Long; Hu, Chang-hui; Zhao, Ya-ping; Dong, Wei-jun

2013-09-01

The distributions, soil environment status and potential ecological risk of heavy metals were studied in beach soil of returning the cropland into Yellow River beach region in Kaifeng by the Nemerows and Håkansons methods. The results showed that (1) as Among the average contents of the five heavy metals Pb, Cr, Hg, As and Cd, the highest was the average content of Cr, and the lowest was the average content of Pb and Hg. In addition to Hg, the coefficients of variation of other heavy metals were relatively small, indicating that the content of heavy metals was quite different at different sites, and to some extent, relecting that Hg, As and Pb were the major elements polluting the soil, among which, Pb pollution was the pollution with universality. There was little difference in the contents of Cr and Cd from village to village the coefficient of variation was small, and the contents were below the national standard level. (2) There was significant difference in the spatial distribution of soil heavy metal elements in the upper, the middle and lower sections of the study area. The upper section was clean, the middle section was slightly polluted, and the lower section was enriched with pollutants. (3) The distribution of heavy metals in the beach region inside and outside the levees of Yellow River was closely related to the distribution of the residential regions. In the upper section of the beach region (southwest), the population was large and the contents of heavy metals were high. The contents of heavy metals were lower in the near river zone than outside the levees of Yellow River. And the heavy metal contents in the middle and lower section were higher than those outside the levees of Yellow River, while the lower section (northwest) showed a tendency of pollution enrichment. (4) In the view of the average individual potential ecological risk index of heavy metals (E(r)i), the potential ecological risk of Hg reached intense levels, and the potential ecological risk of Pb's contribution to the integrated risk was 50.5%, which was the heavy metal with highest ecological risks. Cd and Pb had a moderate ecological risk, while As and Cr had minor ecological risk. Ecological hazards of heavy metals ranked in the ascending order of Hg > Pb > As > Cd > Cr. (5) The ecological hazard of the heavy metals was ranked in the order Hg > Cd > As > Pb > Cr. Based on the potential ecological risk level corresponding to the RI values, it was shown that there was moderate potential ecological risks of heavy metals in the Yellow River beach region in Kaifeng.

Decreasing concentrations of metals in Sphagnum mosses in ombrotrophic mires of the Sudety mountains (SW Poland) since late 1980s.

PubMed

Wojtuń, Bronisław; Samecka-Cymerman, Aleksandra; Kolon, Krzysztof; Kempers, Alexander J

2013-06-01

In this investigation we focus on the evaluation of changes in metal pollution between 1986 until 2011 by Sphagnum species as bioindicators in 100 km part of the Sudety mountains influenced by the former Black Triangle Region. Concentrations of Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn were measured in various Sphagnum species all from ombrotrophic bogs in the Sudety mountains (SW Poland). The tested hypothesis was that overall improvements in pollution control in the former Black Triangle Region between 1986 until recent reduced the amount of metals deposited and accumulated by these plants. Concentrations of Cd, Cr, Cu, Fe, Pb and Zn in Sphagnum species were very high in 1986 indicating a heavy pollution of the examined bogs in this period, and significantly higher than in samples collected in 2011. The PCCA ordination showed the similar pattern in all bogs. In 2011 concentration of the Co was significantly higher in hollow species and concentration of Mn was significantly higher in those from hummocks. Differences between hollow/hummock sites were more important than species-specific abilities of Sphagnum mosses to accumulate metals. Species from hollows were better bioindicators of Co and those from hummocks were better bioindicators of Mn pollution. Copyright © 2012 Elsevier Ltd. All rights reserved.

On the Dominant Factor Controlling Seasonal Hydrological Forecast Skill in China

DOE PAGES

Zhang, Xuejun; Tang, Qiuhong; Leng, Guoyong; ...

2017-11-20

Initial conditions (ICs) and climate forecasts (CFs) are the two primary sources of seasonal hydrological forecast skill. However, their relative contribution to predictive skill remains unclear in China. In this study, we investigate the relative roles of ICs and CFs in cumulative runoff (CR) and soil moisture (SM) forecasts using 31-year (1980–2010) ensemble streamflow prediction (ESP) and reverse-ESP (revESP) simulations with the Variable Capacity Infiltration (VIC) hydrologic model. The results show that the relative importance of ICs and CFs largely depends on climate regimes. The influence of ICs is stronger in a dry or wet-to-dry climate regime that covers themore » northern and western interior regions during the late fall to early summer. In particular, ICs may dominate the forecast skill for up to three months or even six months during late fall and winter months, probably due to the low precipitation value and variability in the dry period. In contrast, CFs become more important for most of southern China or during summer months. The impact of ICs on SM forecasts tends to cover larger domains than on CR forecasts. These findings will greatly benefit future work that will target efforts towards improving current forecast levels for the particular regions and forecast periods.« less

On the Dominant Factor Controlling Seasonal Hydrological Forecast Skill in China

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Xuejun; Tang, Qiuhong; Leng, Guoyong

Initial conditions (ICs) and climate forecasts (CFs) are the two primary sources of seasonal hydrological forecast skill. However, their relative contribution to predictive skill remains unclear in China. In this study, we investigate the relative roles of ICs and CFs in cumulative runoff (CR) and soil moisture (SM) forecasts using 31-year (1980–2010) ensemble streamflow prediction (ESP) and reverse-ESP (revESP) simulations with the Variable Capacity Infiltration (VIC) hydrologic model. The results show that the relative importance of ICs and CFs largely depends on climate regimes. The influence of ICs is stronger in a dry or wet-to-dry climate regime that covers themore » northern and western interior regions during the late fall to early summer. In particular, ICs may dominate the forecast skill for up to three months or even six months during late fall and winter months, probably due to the low precipitation value and variability in the dry period. In contrast, CFs become more important for most of southern China or during summer months. The impact of ICs on SM forecasts tends to cover larger domains than on CR forecasts. These findings will greatly benefit future work that will target efforts towards improving current forecast levels for the particular regions and forecast periods.« less

Assessment of heavy metals contamination in sediments from three adjacent regions of the Yellow River using metal chemical fractions and multivariate analysis techniques.

PubMed

Ma, Xiaoling; Zuo, Hang; Tian, Mengjing; Zhang, Liyang; Meng, Jia; Zhou, Xuening; Min, Na; Chang, Xinyuan; Liu, Ying

2016-02-01

Metal chemical fractions obtained by optimized BCR three-stage extraction procedure and multivariate analysis techniques were exploited for assessing 7 heavy metals (Cr, Pb, Cd, Co, Cu, Zn and Ni) in sediments from Gansu province, Ningxia and Inner Mongolia Autonomous Regions of the Yellow River in Northern China. The results indicated that higher susceptibility and bioavailability of Cr and Cd with a strong anthropogenic source were due to their higher availability in the exchangeable fraction. A portion of Pb, Cd, Co, Zn, and Ni in reducible fraction may be due to the fact that they can form stable complexes with Fe and Mn oxides. Substantial amount of Pb, Co, Ni and Cu was observed as oxidizable fraction because of their strong affinity to the organic matters so that they can complex with humic substances in sediments. The high geo-accumulation indexes (I(geo)) for Cr and Cd showed their higher environmental risk to the aquatic biota. Principal component analysis (PCA) revealed that high toxic Cr and Cd in polluted sites (Cd in S10, S11 and Cr in S13) may be contributed to anthropogenic sources, it was consistent with the results of dual hierarchical clustering analysis (DHCA), which could give more details about contributing sources. Copyright © 2015 Elsevier Ltd. All rights reserved.

Microstructures Evolution and Micromechanics Features of Ni-Cr-Si Coatings Deposited on Copper by Laser Cladding.

PubMed

Zhang, Peilei; Li, Mingchuan; Yu, Zhishui

2018-05-23

Three Ni-Cr-Si coatings were synthesized on the surface of copper by laser cladding. The microstructures of the coatings were characterized by optical microscopy (OM), X-ray diffraction (XRD), and scanning electron microscopy (SEM) with an energy dispersive spectrometer (EDS). According to the analysis results of phase compositions, Gibbs free energy change and microstructures, the phases of three coatings appeared were Cr₃Si+γ-Ni+Cu ss (Coating 1, Ni-26Cr-29Si), Cr₆Ni 16 Si₇+Ni₂Si+Cu ss (Coating 2, Ni-10Cr-30Si) and Cr₃Ni₅Si₂+Cr₂Ni₃+Cu ss (Coating 3, Ni-29Cr-16Si). The crystal growth in the solidification process was analyzed with a modified model, which is a combination of Kurz-Giovanola-Trivedi (KGT) and Lipton-Kurz-Trivedi (LKT) models. The dendrite tip undercooling in Coating 2 was higher than those of Coating 1 and Coating 3. Well-developed dendrites were found in Coating 2. A modification of Hunt’s model was adopted to describe the morphological differences in the three coatings. The results show that Coating 1 was in the equiaxed dendrite region, while Coatings 2 and 3 were in the columnar dendrite region. The average friction coefficients of the three coatings were 0.45, 0.5 and 0.4, respectively. Obvious plastic deformation could be found in the subsurface zone of Coatings 2 and 3.

Evidence for regional hippocampal damage in patients with schizophrenia.

PubMed

Singh, Sadhana; Khushu, Subash; Kumar, Pawan; Goyal, Satnam; Bhatia, Triptish; Deshpande, Smita N

2018-02-01

Schizophrenia patients show cognitive and mood impairments, including memory loss and depression, suggesting damage in the brain regions. The hippocampus is a brain structure that is significantly involved in memory and mood function and shows impairment in schizophrenia. In the present study, we examined the regional hippocampal changes in schizophrenia patients using voxel-based morphometry (VBM), Freesurfer, and proton magnetic resonance spectroscopy ( 1 H MRS) procedures. 1 H MRS and high-resolution T1-weighted magnetic resonance imaging were collected in both healthy control subjects (N = 28) and schizophrenia patients (N = 28) using 3-Tesla whole body MRI system. Regional hippocampal volume was analyzed using VBM and Freesufer procedures. The relative ratios of the neurometabolites were calculated using linear combination model (LCModel). Compared to controls, schizophrenia patients showed significantly decreased gray matter volume in the hippocampus. Schizophrenia patients also showed significantly reduced glutamate (Glu) and myo-inositol (mI) ratios in the hippocampus. Additionally, significant positive correlation between gray matter volume and Glu/tCr was also observed in the hippocampus in schizophrenia. Our findings provide an evidence for a possible association between structural deficits and metabolic alterations in schizophrenia patients.

The influence of coordination geometry and valency on the K-edge absorption near edge spectra of selected chromium compounds

NASA Astrophysics Data System (ADS)

Pantelouris, A.; Modrow, H.; Pantelouris, M.; Hormes, J.; Reinen, D.

2004-05-01

X-ray absorption spectra at the chromium K-edge are reported for a number of selected chromium compounds of known chemical structure. The spectra were obtained with use of synchrotron radiation available at the ELectron Stretcher Accelerator ELSA in Bonn. The compounds studied include the tetrahedrally coordinated compounds Ca 2Ge 0.8Cr 0.2O 4, Ba 2Ge 0.1Cr 0.9O 4, Sr 2CrO 4, Ca 2(PO 4) x(CrO 4) 1- xCl ( x=0.25,0.5), Ca 5(CrO 4) 3Cl, CrO 3, the octahedrally coordinated compounds Cr(II)-acetate, CrCl 3, CrF 3, Cr 2O 3, KCr(SO 4) 2 · 12H 2O, CrO 2 and cubic coordinated metallic chromium. In these compounds chromium exhibits a wide range of formal oxidation states (0 to VI). The absorption features in the near edge region are shown to be characteristic of the spatial environment of the absorbing atom. The occurrence of a single pre-edge line easily allows one to distinguish between tetrahedral and octahedral coordination geometry, whereas the energy position of the absorption edge is found to be very sensitive to the valency of the excited chromium atom. Calculations of the ionisation potential of Cr in different oxidation states using the non-relativistic Hartree-Fock method (Froese-Fischer) confirm that the ionisation limit shifts to higher energy with increasing Cr valency. More detailed information on the electronic structure of the different compounds is gained by real-space full multiple scattering calculations using the FEFF8 code.

High temperature oxidation behavior of ODS steels

NASA Astrophysics Data System (ADS)

Kaito, T.; Narita, T.; Ukai, S.; Matsuda, Y.

2004-08-01

Oxide dispersion strengthened (ODS) steels are being developing for application as advanced fast reactor cladding and fusion blanket materials, in order to allow increased operation temperature. Oxidation testing of ODS steel was conducted under a controlled dry air atmosphere to evaluate the high temperature oxidation behavior. This showed that 9Cr-ODS martensitic steels and 12Cr-ODS ferritic steels have superior high temperature oxidation resistance compared to 11 mass% Cr PNC-FMS and 17 mass% Cr ferritic stainless steel. This high temperature resistance is attributed to earlier formation of the protective α-Cr 2O 3 on the outer surface of ODS steels.

Graphene-gold supercapacitor as a voltage controlled saturable absorber for femtosecond pulse generation.

PubMed

Baylam, Isinsu; Balci, Osman; Kakenov, Nurbek; Kocabas, Coskun; Sennaroglu, Alphan

2016-03-01

We report, for the first time to the best of our knowledge, use of a graphene-gold supercapacitor as a voltage controlled fast saturable absorber for femtosecond pulse generation. The unique design involving only one graphene electrode lowers the insertion loss of the device, in comparison with capacitor designs with two graphene electrodes. Furthermore, use of the high-dielectric electrolyte allows reversible, adjustable control of the absorption level up to the visible region with low bias voltages of only a few volts (0-2 V). The fast saturable absorber action of the graphene-gold supercapacitor was demonstrated inside a multipass-cavity Cr:forsterite laser to generate nearly transform-limited, sub-100 fs pulses at a pulse repetition rate of 4.51 MHz at 1.24 μm.

The arcuate nucleus and NPY contribute to the antitumorigenic effect of calorie restriction

PubMed Central

Minor, Robin K.; López, Miguel; Younts, Caitlin M.; Jones, Bruce; Pearson, Kevin J.; Anson, R. Michael; Diéguez, Carlos; de Cabo, Rafael

2011-01-01

Summary Calorie restriction (CR) is known to have profound effects on tumor incidence. A typical consequence of CR is hunger, and we hypothesized that the neuroendocrine response to CR might in part mediate CR's antitumor effects. We tested CR under appetite suppression using two models: neuropeptide Y (NPY) knockout mice and monosodium glutamate (MSG)-injected mice. While CR was protective in control mice challenged with a two-stage skin carcinogenesis model, papilloma development was neither delayed nor reduced by CR in the MSG-treated and NPY knockout mice. Adiponectin levels were also not increased by CR in the appetite-suppressed mice. We propose that some of CR’s beneficial effects cannot be separated from those imposed on appetite, and that NPY neurons in the arcuate nucleus of the hypothalamus (ARC) are involved in the translation of reduced intake to downstream physiological and functional benefits. PMID:21385308

Multivariate analysis of heavy metal contents in soils, sediments and water in the region of Meknes (central Morocco).

PubMed

Tahri, M; Benyaïch, F; Bounakhla, M; Bilal, E; Gruffat, J J; Moutte, J; Garcia, D

2005-03-01

Concentrations of Al, Fe, Cr, Cu, Ni, Pb and Zn in soils, sediments and water samples collected along the Oued Boufekrane river (Meknes, central Morocco) were determined. In soils, a homogeneous distribution of metal concentrations was observed throughout the study area except for Pb, which presents high enrichment at sites located at the vicinity of a main highway. In sediments, high enrichment, with respect to upstream sites, were observed downstream of the city of Meknes for Al, Cr, Fe and Ni and inside the city for Cu, Zn and Pb. In water samples, the metal contents showed to correlate with their homologues in sediments suggesting that the metal contents in water and sediments have identical origins. Descriptive statistics and multivariate analysis (principal factor method, PFM) were used to assist the interpretation of elemental data. This allowed the determination of the correlations between the metals and the identification of three main factor loadings controlling the metal variability in soils and sediments.

Assessment of metal contamination in coastal sediments of Al-Khobar area, Arabian Gulf, Saudi Arabia

NASA Astrophysics Data System (ADS)

Alharbi, Talal; El-Sorogy, Abdelbaset

2017-05-01

An assessment of marine pollution due to heavy metals was made to coastal sediments collected from Al-Khobar coastline, in the Arabian Gulf, Saudi Arabia by analyzing of Al, V, Cr, Mn, Cu, Zn, Cd, Pb, Hg, Mo, Sr, Se, As, Fe, Co and Ni using Inductively Coupled Plasma-Mass Spectrometer (ICP-MS). The results indicated that the distribution of most metals was largely controlled by inputs of terrigenous material and most strongly associated with distribution of Al in sediments. In general Sr, Cr, Zn, Cu, V, Hg, Mo and Se show severe enrichment factors. Average values of Cu and Hg highly exceed the ERL and the Canadian ISQG values. Average Ni was higher than the ERL and the ERM values. The severe enrichment of some metals in the studied sediment could be partially attributed to anthropogenic activities, notably oil spills from exploration, transportation and from saline water desalination plants in Al-Khobar coast, and other industrial activities in the region.

Insulin-sensitizing and cholesterol-lowering effects of chromium (D-Phenylalanine)3.

PubMed

Yang, Xiaoping; Li, Shi-Yan; Dong, Feng; Ren, Jun; Sreejayan, Nair

2006-07-01

Low-molecular weight organic chromium complexes are thought to play a key role in carbohydrate and lipid metabolism and therefore have been gaining popularity as nutritional supplement for patients with diabetes and concomitant lipid disorders. The aim of the present study was to evaluate the effects of a novel synthetic chromium (d-phenylalanine)(3) complex on insulin-sensitivity, plasma lipid-profile and oxidant stress in a mouse model of type II diabetes. Plasma glucose levels following intraperitoneal insulin-challenge (1U/kg) to obese ob/ob(+/+) mice treated with Cr(d-Phe)(3) (150 microg/kg/day for 6 weeks) were significantly lower compared to vehicle-control (control: 175.8+/-43.2mg/dL versus Cr(d-Phe)(3) 115.3+/-18.0mg/dL, p<0.01, n=12). Total serum cholesterol to high-density lipoprotein ratio was significantly reduced following Cr(d-Phe)(3)-treatment (control: 2.19+/-0.08 versus Cr(d-Phe)(3) 1.63+/-0.05; p<0.05). Hepatic oxidant stress, assessed as malondialdehyde equivalents and protein-carbonyl content were significantly attenuated following Cr(d-Phe)(3) treatment. The complex also inhibited lipid-peroxidation in vitro, in a concentration dependent manner. Taken together, these data suggest that Cr(d-Phe)(3) may be of potential value in the therapy or prophylaxis of insulin-resistance and dyslipidemia associated with obesity.

Built-In Potential in Fe 2 O 3 -Cr 2 O 3 Superlattices for Improved Photoexcited Carrier Separation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kaspar, Tiffany C.; Schreiber, Daniel K.; Spurgeon, Steven R.

2015-12-17

We demonstrate that the different surface terminations exhibited by α-Fe2O3 (hematite) and α-Cr2O3 (eskolaite) in superlattices (SL) of these materials, synthesized with exquisite control by molecular beam epitaxy, determine the heterojunction interface structure and result in controllable, non-commutative band offset values. Precise atomic control of the interface structure allowed us to vary the valence band offset from 0.35 eV to 0.79 eV. This controllable band alignment can be harnessed to generate a built-in potential in Fe2O3-Cr2O3 SLs. For instance, in a 2.5-period SL, a built-in potential of 0.8 eV was realized as measured by x-ray photoelectron spectroscopy of Ti dopantsmore » as probe species. The high quality of the SL structure was confirmed by atom probe tomography and scanning transmission electron microscopy. Enhanced photocurrents were measured for a thick Fe2O3 epitaxial film capped with an (Fe2O3)3-(Cr2O3)3 SL; this enhancement was attributed to efficient electron-hole separation in the SL as a result of the band alignment. The Fe-O-Cr bonds at the SL interfaces also red-shifted the onset of photoconductivity to ~1.6 eV. Exploiting the band alignment and photoabsorption properties of Fe2O3-Cr2O3 SLs has the potential to increase the efficiency of hematite-based photoelectrochemical water splitting.« less

Chondroprotective effects of zoledronic acid on articular cartilage in dogs with experimentally induced osteoarthritis.

PubMed

Dearmin, Michael G; Trumble, Troy N; García, Anapatricia; Chambers, Jon N; Budsberg, Steven C

2014-04-01

To assess effects of zoledronic acid on biomarkers, radiographic scores, and gross articular cartilage changes in dogs with induced osteoarthritis. 21 purpose-bred hound-type dogs. The left stifle joint of each dog was examined arthroscopically to determine initial articular cartilage status, which was followed by cranial cruciate ligament (CrCL) transection to induce osteoarthritis. Dogs were assigned to 3 groups (control group, low dose [10 μg of zoledronic acid/kg], or high dose [25 μg of zoledronic acid/kg). Treatments were administered SC every 3 months for 1 year beginning the day after CrCL transection. Serum and synovial fluid samples and radiographs were obtained 0, 1, 3, 6, 9, and 12 months after transection. At 12 months, each joint was scored for cartilage defects. Serum and synovial fluid biomarkers of bone and cartilage turnover (bone-specific alkaline phosphatase, type I and II collagen, carboxy-propeptide of type II collagen, and chondroitin sulfate 846) were analyzed with ELISAs. The high-dose group had fewer total articular defects and lower severity scores in CrCL-transected stifle joints than did the control group. In addition, the high-dose group had significantly less change in collagenase cleavage of type I or II collagen in the synovial fluid at 1 and 3 months after CrCL transection than did the control group and also had greater changes in bone-specific alkaline phosphatase in synovial fluid at 3 months after CrCL transection than did the control group. Zoledronic acid had a chondroprotective effect in dogs with a transected CrCL.

7 Tesla proton magnetic resonance spectroscopic imaging in adult X-linked adrenoleukodystrophy

PubMed Central

Ratai, Eva; Kok, Trina; Wiggins, Christopher; Wiggins, Graham; Grant, Ellen; Gagoski, Borjan; O'Neill, Gilmore; Adalsteinsson, Elfar; Eichler, Florian

2010-01-01

Background Adult patients with X-linked adrenoleukodystrophy (X-ALD) remain at risk for progressive neurological deterioration. Phenotypes vary in their pathology, ranging from axonal degeneration to inflammatory demyelination. The severity of symptoms is poorly explained by conventional imaging. Objective To test the hypothesis that neurochemistry in normal appearing brain differs among adult phenotypes of X-ALD, and that neurochemical changes correlate with the severity of symptoms. Patients and Methods Using a 7 Tesla scanner we performed structural and proton MRSI in 13 adult patients with X-ALD, including 4 patients with adult cerebral ALD (ACALD), 5 with adrenomyeloneuropathy (AMN) and 4 female heterozygotes. Studies were also performed in nine healthy controls. Results Among adult X-ALD phenotypes, MI/Cr was 46% higher and Cho/Cr 21% higher in normal appearing white matter of ACALD compared to AMN (p < 0.05). Both NAA/Cr and Glu/Cr ratios were lower in AMN patients (p = 0.028 and p = 0.036, respectively) than in controls. There were no significant differences between AMN and female heterozygotes. In cortex, ACALD patients had lower values of NAA/Cr compared to female heterozygotes and controls (p = 0.022). The global MI/Cr ratio demonstrated a significant association with the EDSS (Spearman ρ = 0.66, p = 0.039). Conclusion 7 Tesla proton MRSI reveals differences in the neurochemistry of ACALD but is unable to distinguish AMN from female heterozygotes. MI/Cr correlates with the severity of the symptoms and may be a meaningful biomarker in adult X-ALD. PMID:19001168

Differences between Spinocerebellar Ataxias and Multiple System Atrophy-Cerebellar Type on Proton Magnetic Resonance Spectroscopy

PubMed Central

Chen, Hung-Chieh; Soong, Bing-Wen; Guo, Wan Yuo; Wu, Hsiu-Mei; Chang, Cheng-Yen

2012-01-01

Purpose A broad spectrum of diseases can manifest cerebellar ataxia. In this study, we investigated whether proton magnetic resonance spectroscopy (MRS) may help differentiate spinocerebellar ataxias (SCA) from multiple systemic atrophy- cerebellar type (MSA-C). Material and Methods This prospective study recruited 156 patients with ataxia, including spinocerebellar ataxia (SCA) types 1, 2, 3, 6 and 17 (N = 94) and MSA-C (N = 62), and 44 healthy controls. Single voxel proton MRS in the cerebellar hemispheres and vermis were measured. The differences were evaluated using nonparametric statistic tests. Results When compared with healthy controls, the cerebellar and vermis NAA/Cr and NAA/Cho were lower in all patients(p<0.002). The Cho/Cr was lower in SCA2 and MSA-C (p<0.0005). The NAA/Cr and Cho/Cr were lower in MSA-C or SCA2 comparing with SCA3 or SCA6. The MRS features of SCA1 were in between (p<0.018). The cerebellar NAA/Cho was lower in SCA2 than SCA1, SCA3 or SCA6 (p<0.04). The cerebellar NAA/Cho in MSA-C was lower than SCA3 (p<0.0005). In the early stages of diseases (SARA score<10), significant lower NAA/Cr and NAA/Cho in SCA2, SCA3, SCA6 or MSA-C were observed comparing with healthy controls (p<0.017). The Cho/Cr was lower in MSA-C or SCA2 (p<0.0005). Patients with MSA-C and SCA2 had lower NAA/Cr and Cho/Cr than SCA3 or SCA6 (p<0.016). Conclusion By using MRS, significantly lower NAA/Cr, Cho/Cr and NAA/Cho in the cerebellar hemispheres and vermis were found in patients with ataxia (SCAs and MSA-C). Rapid neuronal degeneration and impairment of membrane activities were observed more often in patients with MSA-C than those with SCA, even in early stages. MRS could also help distinguish between SCA2 and other subtypes of SCAs. MRS ratios may be of use as biomarkers in early stages of disease and should be further assessed in a longitudinal study. PMID:23118909

Similarities of biochemical abnormalities between major depressive disorder and bipolar depression: a proton magnetic resonance spectroscopy study.

PubMed

Zhong, Shuming; Wang, Ying; Zhao, Guoxiang; Xiang, Qi; Ling, Xueying; Liu, Sirun; Huang, Li; Jia, Yanbin

2014-10-01

Depression in the context of bipolar disorder (BD) is often misdiagnosed as major depressive disorder (MDD), leading to mistreatments and poor clinical outcomes for many bipolar patients. Previous neuroimaging studies found mixed results on brain structure, and biochemical metabolism of the two disorders. To eliminate the compounding effects of medication, and aging, this study sought to investigate the brain biochemical changes of treatment-naïve, non-late-life patients with MDD and BD in white matter in prefrontal (WMP) lobe, anterior cingulate cortex (ACC) and hippocampus by using proton magnetic resonance spectroscopy ((1)H-MRS). Three groups of participants were recruited: 26 MDD patients, 20 depressed BD patients, and 13 healthy controls. The multi-voxel (1)H-MRS [repetition time (TR)=1000ms; echo-time (TE)=144ms] was used for the measurement of N-acetylaspartate(NAA), choline containg compounds (Cho), and creatine (Cr) in three brain locations: white matter in prefrontal (WMP) lobe, anterior cingulate cortex (ACC), and hippocampus. Two ratios of NAA/Cr and Cho/Cr as a measure of brain biochemical changes were compared among three experimental groups. On the comparison of brain biochemical changes, both MDD patients and BD patients showed many similarities compared to the controls. They both had a significantly lower NAA/Cr ratio in the left WMP lobe. There were no significant differences among three experimental groups for Cho/Cr ratio in the WMP lobe, and for the ratios of NAA/Cr and Cho/Cr in the bilateral ACC and hippocampus. The only difference between MDD and BD patients existed for the NAA/Cr ratio in the right WMP lobe. While MDD patients had a significantly lower NAA/Cr ratio than controls, BD patients showed no such differences. On the comparison of correlation of medical variables and brain biochemical changes, all participants demonstrated no significant correlations. Reduced NAA/Cr ratio at the left WMP lobe indicated the dysfunction of neuronal viability in deep white matter, in both MDD and BD patients who shared similarities of brain biochemical abnormalities, which might imply an overlap in neuropathology of depression. Copyright © 2014 Elsevier B.V. All rights reserved.

Chromium (VI) induced oxidative damage to DNA: increase of urinary 8-hydroxydeoxyguanosine concentrations (8-OHdG) among electroplating workers

PubMed Central

Kuo, H; Chang, S; Wu, K; Wu, F

2003-01-01

Aims: To investigate the concentration of urinary 8-hydroxydeoxyguanosine (8-OHdG) among electroplating workers in Taiwan. Methods: Fifty workers were selected from five chromium (Cr) electroplating plants in central Taiwan. The 20 control subjects were office workers with no previous exposure to Cr. Urinary 8-OHdG concentrations were determined using high performance liquid chromatography with electrochemical detection. Results: Urinary 8-OHdG concentrations among Cr workers (1149.5 pmol/kg/day) were higher than those in the control group (730.2 pmol/kg/day). There was a positive correlation between urinary 8-OHdG concentrations and urinary Cr concentration (r = 0.447, p < 0.01), and urinary 8-OHdG correlated positively with airborne Cr concentration (r = 0.285). Using multiple regression analysis, the factors that affected urinary 8-OHdG concentrations were alcohol, the common cold, and high urinary Cr concentration. There was a high correlation of urinary 8-OHdG with both smoking and drinking, but multiple regression analysis showed that smoking was not a significant factor. Age and gender were also non-significant factors. Conclusion: 8-OHdG, which is an indicator of oxidative DNA damage, was a sensitive biomarker for Cr exposure. PMID:12883020

Engineering Topological Surface State of Cr-doped Bi2Se3 under external electric field

NASA Astrophysics Data System (ADS)

Zhang, Jian-Min; Lian, Ruqian; Yang, Yanmin; Xu, Guigui; Zhong, Kehua; Huang, Zhigao

2017-03-01

External electric field control of topological surface states (SSs) is significant for the next generation of condensed matter research and topological quantum devices. Here, we present a first-principles study of the SSs in the magnetic topological insulator (MTI) Cr-doped Bi2Se3 under external electric field. The charge transfer, electric potential, band structure and magnetism of the pure and Cr doped Bi2Se3 film have been investigated. It is found that the competition between charge transfer and spin-orbit coupling (SOC) will lead to an electrically tunable band gap in Bi2Se3 film under external electric field. As Cr atom doped, the charge transfer of Bi2Se3 film under external electric field obviously decreases. Remarkably, the band gap of Cr doped Bi2Se3 film can be greatly engineered by the external electric field due to its special band structure. Furthermore, magnetic coupling of Cr-doped Bi2Se3 could be even mediated via the control of electric field. It is demonstrated that external electric field plays an important role on the electronic and magnetic properties of Cr-doped Bi2Se3 film. Our results may promote the development of electronic and spintronic applications of magnetic topological insulator.

Homogeneous and Heterogeneous (Fex, Cr1-x)(OH)3 Precipitation: Implications for Cr Sequestration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dai, Chong; Zuo, Xiaobing; Cao, B

2016-02-16

The formation of (Fe, Cr)(OH)3 nanoparticles determines the fate of aqueous Cr in many aquatic environments. Using small angle X-ray scattering, precipitation rates of (Fe, Cr)(OH)3 nanoparticles in solution and on quartz were quantified from 0.1 mM Fe(III) solutions containing 0 – 0.25 mM Cr(III) at pH = 3.7 ± 0.2. Concentration ratio of aqueous Cr(III)/Fe(III) controlled the chemical composition (x) of (Fex, Cr1-x)(OH)3 precipitates, solutions’ supersaturation with respect to precipitates, and the surface charge of quartz. Therefore, aqueous Cr(III)/Fe(III) ratio affected homogeneous (in solution) and heterogeneous (on quartz) precipitation rates of (Fex, Cr1-x)(OH)3 through different mechanisms. The sequestration mechanismsmore » of Cr(III) in precipitates were also investigated. In solutions with high aqueous Cr(III)/Fe(III) ratios, surface enrichment of Cr(III) on the precipitates occurred, resulting in slower particle growth in solution. From solutions with 0 – 0.1 mM Cr(III), the particles on quartz grew from 2 to 4 nm within 1 h. Interestingly, from solution with 0.25 mM Cr(III), particles of two distinct sizes (2 and 6 nm) formed on quartz, and their sizes remained unchanged throughout the reaction. Our study provided new insights on homogeneous and heterogeneous precipitation of (Fex, Cr1-x)(OH)3 nanoparticles, which can help determine the fate of Cr in aquatic environments.« less

Long-term moderate calorie restriction inhibits inflammation without impairing cell-mediated immunity: a randomized controlled trial in non obese humans

USDA-ARS?s Scientific Manuscript database

Calorie restriction (CR) inhibits inflammation and slows aging in many animal species, but in rodents housed in pathogen-free facilities, CR impairs immunity against certain pathogens. However, little is known about the effects of long-term moderate CR on immune function in humans. In this multi-cen...

Sandstone petrology and geochemistry of the Oligocene-Early Miocene Panjgur Formation, Makran accretionary wedge, southwest Pakistan: Implications for provenance, weathering and tectonic setting

NASA Astrophysics Data System (ADS)

Kassi, Akhtar Muhammad; Grigsby, Jeffry D.; Khan, Abdul Salam; Kasi, Aimal Khan

2015-06-01

The Oligocene-Early Miocene Panjgur Formation is comprised of submarine fan and abyssal plain turbidites deposited within the Makran subduction complex. Sandstones of the formation are litharenite to feldspathic litharenite. Petrographic data indicates a quartzose-recycled provenance dominated by plutonic and metamorphic fragments. Major elements concentrations reveal a moderate level of mineralogical maturity and high values of Chemical Proxy of Alteration (CPA; 88.29) coupled with a high Th/U ratio (9.37), which reveals intense weathering in the source area. The Zr, Nb, Y, and Th concentrations are comparable to upper continental crust (UCC) values and trends in Th/Cr, Th/Co, and Cr/Zr ratios support contribution from a felsic source. However, enrichment in Ni and Cr, reinforced by trends in Ni/Co, Cr/V, V/Ni and Y/Ni ratios, reveals mixing of the felsic source with mafic/ultramafic source terrains. Tectonic discrimination plots suggest continental arc to active continental margin setting. This study supports the Katawaz-delta-Panjgur submarine fan model and upholds the initial southward transport of predominantly felsic detritus from the Himalayan orogenic belt controlled by the Chaman-Ornach Nal transform fault system. This study further adds that the Bela-Muslimbagh ophiolites, associated mélanges and the West Pakistan Fold-Thrust Belt, from the east, and the Chagai-Raskoh volcanic arc, from the west, were also concurrently shedding mafic/ultramafic detritus to the basin, and that the depositional system in the Makran region turned westward, roughly parallel to the present active margin of the Makran accretionary wedge.

Transport of chromium and selenium in the suboxic zone of a shallow aquifer: Influence of redox and adsorption reactions

USGS Publications Warehouse

Kent, D.B.; Davis, J.A.; Anderson, L.C.D.; Rea, B.A.; Waite, T.D.

1994-01-01

Breakthrough of Cr(VI) (chromate), Se(VI) (selenate), and O2 (dissolved oxygen) was observed in tracer tests conducted in a shallow, sand and gravel aquifer with mildly reducing conditions. Loss of Cr, probably due to reduction of Cr(VI) to Cr(III) and irreversible sorption of Cr(III), occurred along with slight retardation of Cr(VI), owing to reversible sorption. Reduction of Se(VI) and O2 was thermodynamically feasible but did not occur, indicating conditions, were unfavorable to microbial reduction. Cr(VI) reduction by constituents of aquifer sediments did not achieve local equilibrium during transport. The reduction rate was probably limited by incomplete contact between Cr(VI) transported along predominant flow paths and reductants located in regions within aquifer sediments of comparatively low permeability. Scatter in the amount of Cr reduction calculated from individual breakthrough curves at identical distances downgradient probably resulted from heterogeneities in the distribution of reductants in the sediments. Predictive modeling of the transport and fate of redox-sensitive solutes cannot be based strictly on thermodynamic considerations; knowledge of reaction rates is critical. Potentially important mass transfer rate limitations between solutes and reactants in sediments as well as heterogeneities in the distribution of redox properties in aquifers complicate determination of limiting rates for use in predictive simulations of the transport of redox-sensitive contaminants in groundwater.

Power and efficiency scaling of diode pumped Cr:LiSAF lasers: 770-1110 nm tuning range and frequency doubling to 387-463 nm.

PubMed

Demirbas, Umit; Baali, Ilyes

2015-10-15

We report significant average power and efficiency scaling of diode-pumped Cr:LiSAF lasers in continuous-wave (cw), cw frequency-doubled, and mode-locked regimes. Four single-emitter broad-area laser diodes around 660 nm were used as the pump source, which provided a total pump power of 7.2 W. To minimize thermal effects, a 20 mm long Cr:LiSAF sample with a relatively low Cr-concentration (0.8%) was used as the gain medium. In cw laser experiments, 2.4 W of output power, a slope efficiency of 50%, and a tuning range covering the 770-1110 nm region were achieved. Intracavity frequency doubling with beta-barium borate (BBO) crystals generated up to 1160 mW of blue power and a record tuning range in the 387-463 nm region. When mode locked with a saturable absorber mirror, the laser produced 195 fs pulses with 580 mW of average power around 820 nm at a 100.3 MHz repetition rate. The optical-to-optical conversion efficiency of the system was 33% in cw, 16% in cw frequency-doubled, and 8% in cw mode-locked regimes.

C-Cr segregation at grain boundary before the carbide nucleation in Alloy 690

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li Hui, E-mail: huili@shu.edu.cn; Laboratory for Microstructures, Shanghai University, Shanghai, 200444; Xia Shuang

2012-04-15

The grain boundary segregation in Alloy 690 was investigated by atom probe tomography. B, C and Si segregated at the grain boundary. The high concentration regions for each segregation element form a set of straight arrays that are parallel to each other in the grain boundary plane. The concentration fluctuation has a periodicity of about 7 nm in the grain boundary plane. Before the Cr{sub 23}C{sub 6} nucleation at grain boundaries, the C-Cr co-segregate on one side of the grain boundaries while not the exact grain boundary core regions have been detected. The reasons why grain boundary carbides have coherentmore » orientation relationship only with one side of nearby grain which grain boundary is located at high index crystal plane were discussed. - Highlights: Black-Right-Pointing-Pointer Grain boundary segregation in Alloy 690 was investigated by atom probe tomography. Black-Right-Pointing-Pointer B, C and Si segregate at the grain boundary. Black-Right-Pointing-Pointer Concentration of segregated atoms periodicity fluctuated in the grain boundary plane. Black-Right-Pointing-Pointer C and Cr co-segregate on one side of the grain boundary before carbide nucleation.« less

Closely related NDM-1-encoding plasmids from Escherichia coli and Klebsiella pneumoniae in Taiwan.

PubMed

Chen, Chao-Ju; Wu, Tsu-Lan; Lu, Po-Liang; Chen, Ying-Tsong; Fung, Chang-Phone; Chuang, Yin-Ching; Lin, Jung-Chung; Siu, L Kristopher

2014-01-01

Two plasmids carrying blaNDM-1 isolated from carbapenem-resistant Klebsiella pneumoniae (CR-KP) and carbapenem-resistant Escherichia coli (CR-EC) were sequenced. CR-KP and CR-EC were isolated from two Taiwanese patients without travel histories. Complete sequencing of the plasmids (pLK75 and pLK78) was conducted using a shotgun approach. Annotation of the contigs was performed using the RAST Server, followed by manual inspection and correction. These similar plasmids were obtained from two patients with overlapping stays at the same hospital. The pLK75 and pLK78 plasmids were 56,489-bp and 56,072-bp in length, respectively. Plasmid annotation revealed a common backbone similar to the IncN plasmid pR46. The regions flanking the blaNDM-1 genes in these plasmids were very similar to plasmid pNDM-HU01 in Japan, which contains a complex class 1 integron located next to an ISCR1 element. The ISCR1 element has been suggested to provide a powerful mechanism for mobilising antibiotic resistance genes. Two indigenous NDM-1-producing Enterobacteriaceae cases were identified for the first time in Taiwan, highlighting the alarming introduction of NDM-1-producing Enterobacteriaceae in this region.

Concussive brain injury from explosive blast

PubMed Central

de Lanerolle, Nihal C; Hamid, Hamada; Kulas, Joseph; Pan, Jullie W; Czlapinski, Rebecca; Rinaldi, Anthony; Ling, Geoffrey; Bandak, Faris A; Hetherington, Hoby P

2014-01-01

Objective Explosive blast mild traumatic brain injury (mTBI) is associated with a variety of symptoms including memory impairment and posttraumatic stress disorder (PTSD). Explosive shock waves can cause hippocampal injury in a large animal model. We recently reported a method for detecting brain injury in soldiers with explosive blast mTBI using magnetic resonance spectroscopic imaging (MRSI). This method is applied in the study of veterans exposed to blast. Methods The hippocampus of 25 veterans with explosive blast mTBI, 20 controls, and 12 subjects with PTSD but without exposure to explosive blast were studied using MRSI at 7 Tesla. Psychiatric and cognitive assessments were administered to characterize the neuropsychiatric deficits and compare with findings from MRSI. Results Significant reductions in the ratio of N-acetyl aspartate to choline (NAA/Ch) and N-acetyl aspartate to creatine (NAA/Cr) (P < 0.05) were found in the anterior portions of the hippocampus with explosive blast mTBI in comparison to control subjects and were more pronounced in the right hippocampus, which was 15% smaller in volume (P < 0.05). Decreased NAA/Ch and NAA/Cr were not influenced by comorbidities – PTSD, depression, or anxiety. Subjects with PTSD without blast had lesser injury, which tended to be in the posterior hippocampus. Explosive blast mTBI subjects had a reduction in visual memory compared to PTSD without blast. Interpretation The region of the hippocampus injured differentiates explosive blast mTBI from PTSD. MRSI is quite sensitive in detecting and localizing regions of neuronal injury from explosive blast associated with memory impairment. PMID:25493283

Dietary supplementation of l-arginine and chromium picolinate in sows during gestation affects the muscle fibre characteristics but not the performance of their progeny.

PubMed

Shi, Zhan; Song, Wentao; Sun, Yuecheng; Wang, Liansheng; Shi, Baoming; Shan, Anshan; Bi, Zhongpeng

2018-01-01

The present study investigated the effects of dietary supplementation of l-arginine and chromium picolinate (CrP) in sows during gestation on muscle fibre characteristics, performance and carcass characteristics of their progeny. Sixty healthy sows were randomly divided into four groups as a 2 × 2 factorial experiment design: one group received the control diet, another received the control diet + 10 g kg -1 l-arginine, the third group received the control diet + 400 ppb CrP, and the fourth group received the control diet + 10 g kg -1 l-arginine and 400 ppb CrP. The results showed that sows fed the diet supplemented with CrP produced progeny with higher muscle fibre numbers at birth, weaning and slaughter compared to sows fed the control diet. For mean fibre areas, the same result was found at weaning. For progeny of sows fed diets supplemented with l-arginine, only higher muscle fibre numbers at slaughter was observed. Almost no differences were observed regarding average daily gains, average daily feed intake, gain-to-feed ratios, carcass and meat traits. The results of the present study indicate that dietary supplementation of l-arginine and particularly CrP in sows during gestation alters muscle fibre numbers in their offspring, although not their performance or carcass characteristics. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Cognitive Remediation in Middle-Aged or Older Inpatients with Chronic Schizophrenia: A Randomized Controlled Trial in Korea.

PubMed

Choi, Kee-Hong; Kang, Jinsook; Kim, Sun-Min; Lee, Seung-Hwan; Park, Seon-Cheol; Lee, Won-Hye; Choi, Sun; Park, Kiho; Hwang, Tae-Yeon

2017-01-01

Background: Accumulating evidence indicates that cognitive remediation (CR) is effective for improving various cognitive deficits in adult patients with schizophrenia. Although reports of brain plasticity in older adults and the service needs for chronic patients with schizophrenia are increasing, very few randomized controlled trials of CR have been conducted in middle-aged or older inpatients with chronic schizophrenia. We investigated the efficacy of individualized CR on the cognitive impairments of middle-aged or older inpatients with chronic schizophrenia within the context of comprehensive psychiatric rehabilitation (PR) by comparing the results obtained with PR only and treatment as usual (TAU). Method: Fifty-seven middle-aged and older individuals with chronic schizophrenia and mild to moderate cognitive deficits were enrolled. Thirty-eight who were undergoing PR were randomly assigned to CR + PR ( N = 19) or PR-only ( N = 19) groups. Nineteen participants who were undergoing TAU without CR or PR were evaluated pre- and post-treatment. Results: CR was easily provided and well received (drop-out rates = 5.3%) by middle-aged or older psychiatric inpatients. Compared to the PR-Only or TAU patients, patients in the CR + PR group showed greater improvement in executive functioning. Compared to TAU patients, CR + PR and PR-only patients showed greater improvement in logical memory. More patients in the CR + PR group improved clinically significantly in executive functioning and logical memory, compared with the PR-only and TAU patients. Conclusions: These results suggested that CR improved some cognitive deficits in middle-aged or older inpatients with chronic schizophrenia and that it was effective as an adjunctive treatment to the usual PR services provided in inpatient settings. Clinical Registration: KCT0002609.

Pretreatment of Cr(VI)-amended soil with chromate-reducing rhizobacteria decreases plant toxicity and increases the yield of Pisum sativum.

PubMed

Soni, Sumit K; Singh, Rakshapal; Singh, Mangal; Awasthi, Ashutosh; Wasnik, Kundan; Kalra, Alok

2014-05-01

Pot culture experiments were performed under controlled greenhouse conditions to investigate whether four Cr(VI)-reducing bacterial strains (SUCR44, SUCR140, SUCR186, and SUCR188) were able to decrease Cr toxicity to Pisum sativum plants in artificially Cr(VI)-contaminated soil. The effect of pretreatment of soil with chromate-reducing bacteria on plant growth, chromate uptake, bioaccumulation, nodulation, and population of Rhizobium was found to be directly influenced by the time interval between bacterial treatment and seed sowing. Pretreatment of soil with SUCR140 (Microbacterium sp.) 15 days before sowing (T+15) showed a maximum increase in growth and biomass in terms of root length (93 %), plant height (94 %), dry root biomass (99 %), and dry shoot biomass (99 %). Coinoculation of Rhizobium with SUCR140 further improved the aforementioned parameter. Compared with the control, coinoculation of SUCR140+R showed a 117, 116, 136, and 128 % increase, respectively, in root length, plant height, dry root biomass, and dry shoot biomass. The bioavailability of Cr(VI) decreased significantly in soil (61 %) and in uptake (36 %) in SUCR140-treated plants; the effects of Rhizobium, however, either alone or in the presence of SUCR140, were not significant. The populations of Rhizobium (126 %) in soil and nodulation (146 %) in P. sativum improved in the presence of SUCR140 resulting in greater nitrogen (54 %) concentration in the plants. This study shows the usefulness of efficient Cr(VI)-reducing bacterial strain SUCR140 in improving yields probably through decreased Cr toxicity and improved symbiotic relationship of the plants with Rhizobium. Further decrease in the translocation of Cr(VI) through improved nodulation by Rhizobium in the presence of efficient Cr-reducing bacterial strains could also decrease the accumulation of Cr in shoots.

Reduction of Cr(VI) to Cr(III) by green rust - sulphate

NASA Astrophysics Data System (ADS)

Skovbjerg, L.; Stipp, S.

2003-04-01

Chromium is widely used in industrial processes such as leather tanning, electro-plating and as colour pigments. Unfortunately, hexavalent chromium is both toxic and very soluble so it can be a problem for groundwater resources. Given the right redox conditions, however, Cr(VI) can be reduced to trivalent chromium, which is much less soluble and is an essential trace nutrient. Fe(II), an element common in soil and sediments under anaerobic conditions, can serve as a reducing agent for Cr(VI). Green Rust (GR) is a layered Fe(II),Fe(III)-hydroxide with various anions compensating charge in the interlayers. It is very effective in reducing Cr(VI) to Cr(III). GR exists in nature and is thought to be precursor for the formation of Fe(III)-oxides and oxyhydroxides at the redox boundary. It may be that the formation of GR is a key process in the effectiveness of reactive barriers for groundwater remediation that are based on Fe(0). The purpose of this work is to investigate the mechanisms controlling Cr(VI) reduction by Green Rust, to examine the effect of Cr adsorption and incorporation on GR morphology and composition, and to define the role of parameters such as interlayer anion, initial Cr(VI) concentration and time. We are using freshly synthesised material that has not been dried to avoid structural changes that may accompany dehydration and rehydration. X-Ray Diffraction (XRD) is used to characterise mineral structural changes and Atomic Force Microscopy (AFM), to examine changes in morphology as reactions take place. By adjusting the concentration of Cr(VI), we can control the rate of surface change and we can observe the nanoscale particles directly.

Cardiac rehabilitation delivery model for low-resource settings.

PubMed

Grace, Sherry L; Turk-Adawi, Karam I; Contractor, Aashish; Atrey, Alison; Campbell, Norm; Derman, Wayne; Melo Ghisi, Gabriela L; Oldridge, Neil; Sarkar, Bidyut K; Yeo, Tee Joo; Lopez-Jimenez, Francisco; Mendis, Shanthi; Oh, Paul; Hu, Dayi; Sarrafzadegan, Nizal

2016-09-15

Cardiovascular disease is a global epidemic, which is largely preventable. Cardiac rehabilitation (CR) is demonstrated to be cost-effective and efficacious in high-income countries. CR could represent an important approach to mitigate the epidemic of cardiovascular disease in lower-resource settings. The purpose of this consensus statement was to review low-cost approaches to delivering the core components of CR, to propose a testable model of CR which could feasibly be delivered in middle-income countries. A literature review regarding delivery of each core CR component, namely: (1) lifestyle risk factor management (ie, physical activity, diet, tobacco and mental health), (2) medical risk factor management (eg, lipid control, blood pressure control), (3) education for self-management and (4) return to work, in low-resource settings was undertaken. Recommendations were developed based on identified articles, using a modified GRADE approach where evidence in a low-resource setting was available, or consensus where evidence was not. Available data on cost of CR delivery in low-resource settings suggests it is not feasible to deliver CR in low-resource settings as is delivered in high-resource ones. Strategies which can be implemented to deliver all of the core CR components in low-resource settings were summarised in practice recommendations, and approaches to patient assessment proffered. It is suggested that CR be adapted by delivery by non-physician healthcare workers, in non-clinical settings. Advocacy to achieve political commitment for broad delivery of adapted CR services in low-resource settings is needed. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Modulation of hexavalent chromium toxicity on Οriganum vulgare in an acidic soil amended with peat, lime, and zeolite.

PubMed

Antoniadis, Vasileios; Zanni, Anna A; Levizou, Efi; Shaheen, Sabry M; Dimirkou, Anthoula; Bolan, Nanthi; Rinklebe, Jörg

2018-03-01

Dynamics of chromate (Cr(VI)) in contaminated soils may be modulated by decreasing its phytoavailability via the addition of organic matter-rich amendments, which might accelerate Cr(VI) reduction to inert chromite (Cr(III)) or high-cation exchange capacity amendments. We studied Cr(VI) phytoavailability of oregano in a Cr(VI)-spiked acidic soil non-treated (S) and treated with peat (SP), lime (SL), and zeolite (SZ). The addition of Cr(VI) increased the concentrations of Cr(VI) and Cr(III) in soils and plants, especially in the lime-amended soil. The plant biomass decreased in the lime-amended soil compared to the un-spiked soil (control) due to decreased plant phosphorus concentrations and high Cr(VI) concentrations in root at that treatment. Oregano in the peat-amended soil exhibited significantly less toxic effects, due to the role of organic matter in reducing toxic Cr(VI) to Cr(III) and boosted plant vigour in this treatment. In the lime-amended soil, the parameters of soil Cr(VI), soil Cr(III), and root Cr(III) increased significantly compared to the non-amended soil, indicating that Cr(VI) reduction to Cr(III) was accelerated at high pH. Added zeolite failed to decreased Cr(VI) level to soil and plant. Oregano achieved a total uptake of Cr(III) and Cr(VI) of 0.275 mg in plant kg -1 soil in a pot in the non-amended soil. We conclude that peat as soil amendment might be considered as a suitable option for decreasing Cr(VI) toxicity in soil and plant, and that oregano as tolerant plant species has a certain potential to be used as a Cr accumulator. Copyright © 2017 Elsevier Ltd. All rights reserved.

Kinetics and Products of Chromium(VI) Reduction by Iron(II/III)-Bearing Clay Minerals.

PubMed

Joe-Wong, Claresta; Brown, Gordon E; Maher, Kate

2017-09-05

Hexavalent chromium is a water-soluble pollutant, the mobility of which can be controlled by reduction of Cr(VI) to less soluble, environmentally benign Cr(III). Iron(II/III)-bearing clay minerals are widespread potential reductants of Cr(VI), but the kinetics and pathways of Cr(VI) reduction by such clay minerals are poorly understood. We reacted aqueous Cr(VI) with two abiotically reduced clay minerals: an Fe-poor montmorillonite and an Fe-rich nontronite. The effects of ionic strength, pH, total Fe content, and the fraction of reduced structural Fe(II) [Fe(II)/Fe(total)] were examined. The last variable had the largest effect on Cr(VI) reduction kinetics: for both clay minerals, the rate constant of Cr(VI) reduction varies by more than 3 orders of magnitude with Fe(II)/Fe(total) and is described by a linear free energy relationship. Under all conditions examined, Cr and Fe K-edge X-ray absorption near-edge structure spectra show that the main Cr-bearing product is a Cr(III)-hydroxide and that Fe remains in the clay structure after reacting with Cr(VI). This study helps to quantify our understanding of the kinetics of Cr(VI) reduction by Fe(II/III)-bearing clay minerals and may improve predictions of Cr(VI) behavior in subsurface environments.

Effect of d electrons on defect properties in equiatomic NiCoCr and NiCoFeCr concentrated solid solution alloys

DOE PAGES

Zhao, Shijun; Egami, Takeshi; Stocks, G. Malcolm; ...

2018-01-01

Here, the role of d electrons in determining distributions of formation and migration energies for point defects in equiatomic NiCoCr and NiCoFeCr concentrated solid solution alloys (CSAs) are studied regarding electron density deformation flexibility based on first-principles calculations. The disordered state is taken into account by constructing special quasirandom structures. The migration barriers are determined by directly optimizing the saddle point. It is found that the formation energies of interstitials in CSAs are lower than those in pure Ni, whereas the formation energies of vacancies are higher. In both NiCoCr and NiCoFeCr, Co-related dumbbell interstitials exhibit lower formation energies. Notably,more » the distributions of migration energies for Cr interstitials and vacancies exhibit a remarkable overlap region. A detailed analysis of electronic properties reveals that the electronic charge deformation flexibility regarding e g to t 2g transition has a dominant effect on defect energetics for different elements in CSAs. Thus the electron deformation ability is suggested as a key factor in understanding the peculiar defect behavior in CSAs.« less

Effect of d electrons on defect properties in equiatomic NiCoCr and NiCoFeCr concentrated solid solution alloys

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Shijun; Egami, Takeshi; Stocks, G. Malcolm

Here, the role of d electrons in determining distributions of formation and migration energies for point defects in equiatomic NiCoCr and NiCoFeCr concentrated solid solution alloys (CSAs) are studied regarding electron density deformation flexibility based on first-principles calculations. The disordered state is taken into account by constructing special quasirandom structures. The migration barriers are determined by directly optimizing the saddle point. It is found that the formation energies of interstitials in CSAs are lower than those in pure Ni, whereas the formation energies of vacancies are higher. In both NiCoCr and NiCoFeCr, Co-related dumbbell interstitials exhibit lower formation energies. Notably,more » the distributions of migration energies for Cr interstitials and vacancies exhibit a remarkable overlap region. A detailed analysis of electronic properties reveals that the electronic charge deformation flexibility regarding e g to t 2g transition has a dominant effect on defect energetics for different elements in CSAs. Thus the electron deformation ability is suggested as a key factor in understanding the peculiar defect behavior in CSAs.« less

Electronic and optical properties of Cr-, B-doped, and (Cr, B)-codoped SrTiO3

NASA Astrophysics Data System (ADS)

Wu, Jiao; Huang, Wei-Qing; Yang, Ke; Wei, Zeng-Xi; Peng, P.; Huang, Gui-Fang

2017-04-01

Energy band engineering of semiconductors plays a crucial role in exploring high-efficiency visible-light response photocatalysts. Herein, we systematically study the electronic properties and optical response of Cr-, B-doped SrTiO3, and (Cr, B)-codoped SrTiO3 by using first-principles calculations to explore the mechanism for its superior photocatalytic activities in the visible light region. Special emphasis is placed on uncovering the synergy effects of nonmetal B dopant with metal Cr dopant at different cation sites. It is found that the electronic properties and optical absorption of SrTiO3 can be dramatically engineered by mono- or co-doping. In particular, the intermediate levels lying in the bandgap of the codoped SrTiO3 relay on the Cr impurity doped at Sr or Ti cation sites. Moreover, the (Cr@Sr, B@O)-SrTiO3 retains the charge balancing without the generation of unexpected oxygen vacancies, and is more desirable for solar light harvesting due to its higher absorption than others in the entire visible light. The findings can rationalize the available experimental results and are helpful in designing SrTiO3-based photocatalysts with high-efficiency performance.

Beneficial effects of oral chromium picolinate supplementation on glycemic control in patients with type 2 diabetes: A randomized clinical study.

PubMed

Paiva, Ana N; Lima, Josivan G de; Medeiros, Anna C Q de; Figueiredo, Heverton A O; Andrade, Raiana L de; Ururahy, Marcela A G; Rezende, Adriana A; Brandão-Neto, José; Almeida, Maria das G

2015-10-01

Chromium is an essential mineral that contributes to normal glucose function and lipid metabolism. This study evaluated the effect of chromium picolinate (CrPic) supplementation in patients with type 2 diabetes mellitus (T2DM). A four month controlled, single blind, randomized trial was performed with 71 patients with poorly controlled (hemoglobin A1c [HbA1c]>7%) T2DM divided into 2 groups: Control (n=39, using placebo), and supplemented (n=32, using 600μg/day CrPic). All patients received nutritional guidance according to the American Diabetes Association (ADA), and kept using prescribed medications. Fasting and postprandial glucose, HbA1c, total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, triglycerides and serum ferritin were evaluated. CrPic supplementation significantly reduced the fasting glucose concentration (-31.0mg/dL supplemented group; -14.0mg/dL control group; p<0.05, post- vs. pre-treatment, in each group) and postprandial glucose concentration (-37.0mg/dL in the supplemented group; -11.5 mg/dL in the control group; p<0.05). HbA1c values were also significantly reduced in both groups (p<0.001, comparing post- vs. pre-treatment groups). Post-treatment HbA1c values in supplemented patients were significantly lower than those of control patients. HbA1c lowering in the supplemented group (-1.90), and in the control group (-1.00), was also significant, comparing pre- and post-treatment values, for each group (p<0.001 and p<0.05, respectively). CrPic increased serum chromium concentrations (p<0.001), when comparing the supplemented group before and after supplementation. No significant difference in lipid profile was observed in the supplemented group; however, total cholesterol, HDL-c and LDL-c were significantly lowered, comparing pre- and post-treatment period, in the control group (p<0.05). CrPic supplementation had a beneficial effect on glycemic control in patients with poorly controlled T2DM, without affecting the lipid profile. Additional studies are necessary to investigate the effect of long-term CrPic supplementation. Copyright © 2015 Elsevier GmbH. All rights reserved.

An Evolutionarily Conserved DOF-CONSTANS Module Controls Plant Photoperiodic Signaling1[OPEN

PubMed Central

2015-01-01

The response to daylength is a crucial process that evolved very early in plant evolution, entitling the early green eukaryote to predict seasonal variability and attune its physiological responses to the environment. The photoperiod responses evolved into the complex signaling pathways that govern the angiosperm floral transition today. The Chlamydomonas reinhardtii DNA-Binding with One Finger (CrDOF) gene controls transcription in a photoperiod-dependent manner, and its misexpression influences algal growth and viability. In short days, CrDOF enhances CrCO expression, a homolog of plant CONSTANS (CO), by direct binding to its promoter, while it reduces the expression of cell division genes in long days independently of CrCO. In Arabidopsis (Arabidopsis thaliana), transgenic plants overexpressing CrDOF show floral delay and reduced expression of the photoperiodic genes CO and FLOWERING LOCUS T. The conservation of the DOF-CO module during plant evolution could be an important clue to understanding diversification by the inheritance of conserved gene toolkits in key developmental programs. PMID:25897001

Adsorptive removal of Congo red from aqueous solutions using crosslinked chitosan and crosslinked chitosan immobilized bentonite.

PubMed

Huang, Ruihua; Zhang, Lujie; Hu, Pan; Wang, Jing

2016-05-01

Batch experiments were executed to investigate the removal of Congo red (CR) from aqueous solutions using the crosslinked chitosan (CCS) and crosslinked chitosan immobilized bentonite (CCS/BT composite). The CCS and CCS/BT composite were characterized by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) techniques. The removal of CR was examined as a function of pH value of CR solution, contact time, and inorganic sodium salt and ionic strength. The equilibrium data of CCS and CCS/BT composite agreed well with the Langmuir model. The adsorption capacities of CCS and CCS/BT composite at 298K and natural pH value were 405 and 500 mg/g, respectively. The kinetic data correlated well with the pseudo-second-order model. The adsorption of CR onto the CCS was mainly controlled by chemisorption while the adsorption of CR onto the CCS/BT composite was controlled by chemisorption and the electrostatic attraction. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of phentermine and phenformin on biomarkers of aging in rats.

PubMed

Anisimov, Vladimir N; Ukraintseva, Svetlana V; Anikin, Ivan V; Popovich, Irina G; Zabezhinski, Mark A; Bertsein, Lev M; Arutjunyan, Alexander V; Ingram, Donald K; Lane, Mark A; Roth, George S

2005-01-01

Caloric restriction (CR) is the only treatment known to substantially prolong both average and maximal life span in experimental animals. Interventions that mimic certain effects of CR could be potential anti-aging treatments in humans. Drugs which reduce appetite (anorexiants) represent one class of candidate treatments. Agents that reduce the glucose utilization by the organism could also represent another class of candidate CR mimetics. In our study, we addressed the following questions: (1) Does treatment with an anorexiant reduce caloric intake and body weight of experimental animals comparable to that caused by CR? (2) Does treatment with an antidiabetic agent influence caloric intake and body weight? (3) Does treatment with any of these drugs affect metabolic parameters of an organism in the way similar to that observed with CR? One hundred and twenty 6-month-old female Wistar-derived LIO rats were randomly subdivided into four groups and exposed to: (1) ad libitum feeding with placebo (controls); (2) the antidiabetic drug phenformin (2 mg/kg); (3) the anorectic drug phentermine (1 mg/kg), and (4) the same amount of food as the group with the least food intake during the previous week (pair-fed controls). Food and water intake, body weight, and rectal temperature were measured weekly during 16 weeks. At the end of the 16th week of the experiment, serum levels of glucose, total beta-lipoprotein and pre-beta-lipoprotein fractions, cholesterol, triglycerides, insulin, total triiodothyronine, and free thyroxine were estimated. The contents of diene conjugates and Schiff's bases, total antioxidant activity, the activities of Cu/Zn superoxide dismutase, glutathione S-transferase, and glutathione peroxidase, and the generation of reactive oxygen species (ROS) were studied in brain and liver homogenates and in the serum. The controls exposed to pair feeding had a significantly reduced food consumption (about 20%) as compared with the ad libitum fed controls and thus exhibited a moderate CR. Treatment with phentermine reduced the caloric intake by about 12% as compared with the ad libitum fed controls. Body weight and water intake in this group were only slightly decreased (by about 2 and 5%, respectively) as compared with the controls. The mean rectal temperature in the phentermine group (38 degrees C) was significantly higher than in the ad libitum fed (37.8 degrees C) and pair-fed (37.6 degrees C) controls. Treatment with phentermine also resulted in significantly reduced ROS levels in all tissues studied, while the highest ROS production was found in ad libitum (blood serum) and pair-fed (brain) controls. Treatment with phenformin did not significantly influence food and water consumption, body weight, and temperature when compared with the ad libitum fed controls. Rats treated with this antidiabetic drug showed intermediate values of ROS generation. Differences among the groups in total antioxidant activity were not obvious. Treatment with phentermine reduces caloric intake slightly less than is commonly observed in CR studies. CR due to forcibly reduced feeding and CR due to substance-suppressed appetite appear to act through different metabolic mechanisms and thus may affect aging and longevity in different ways. Copyright (c) 2005 S. Karger AG, Basel