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1

Core features of frontotemporal dementia recapitulated in progranulin knockout mice  

PubMed Central

Frontotemporal dementia (FTD) is typified by behavioral and cognitive changes manifested as altered social comportment and impaired memory performance. To investigate the neurodegenerative consequences of progranulin gene (GRN) mutations, which cause an inherited form of FTD, we used previously generated progranulin knockout mice (Grn-/-). Specifically, we characterized two cohorts of early and later middle-age wild type and knockout mice using a battery of tests to assess neurological integrity and behavioral phenotypes analogous to FTD. The Grn-/- mice exhibited reduced social engagement and learning and memory deficits. Immunohistochemical approaches were used to demonstrate the presence of lesions characteristic of frontotemporal lobar degeneration (FTLD) with GRN mutation including ubiquitination, microgliosis, and reactive astrocytosis, the pathological substrate of FTD. Importantly, Grn-/- mice also have decreased overall survival compared to Grn+/+ mice. These data suggest that the Grn-/- mouse reproduces some core features of FTD with respect to behavior, pathology, and survival. This murine model may serve as a valuable in vivo model of FTLD with GRN mutation through which molecular mechanisms underlying the disease can be further dissected.

Ghoshal, N.; Dearborn, J.T.; Wozniak, D.F.; Cairns, N.J.

2011-01-01

2

Software for Demonstration of Features of Chain Polymerization Processes  

ERIC Educational Resources Information Center

Free software for the demonstration of the features of homo- and copolymerization processes (free radical, controlled radical, and living) is described. The software is based on the Monte Carlo algorithms and offers insight into the kinetics, molecular weight distribution, and microstructure of the macromolecules formed in those processes. It also…

Sosnowski, Stanislaw

2013-01-01

3

Neuropeptide B-deficient mice demonstrate hyperalgesia in response to inflammatory pain  

PubMed Central

Neuropeptide B (NPB) and neuropeptide W (NPW) have been recently identified as ligands for the G protein-coupled receptor (GPR) 7 and GPR8. The precise in vivo role of this neuropeptide-receptor pathway has not been fully demonstrated. In this paper, we report that NPB-deficient mice manifest a mild adult-onset obesity, similar to that reported in GPR7-null mice. NPB-deficient mice also exhibit hyperalgesia in response to inflammatory pain. Hyperalgesia was not observed in response to chemical pain, thermal pain, or electrical stimulation. NPB-deficient mice demonstrated intact behavioral responses to pain, and learning from the negative reinforcement of electrical stimulation was unaltered. Baseline anxiety was also unchanged as measured in both the elevated plus maze and time spent immobile in a novel environment. These data support the idea that NPB is a factor in the modulation of responses to inflammatory pain and body weight homeostasis.

Kelly, Michele A.; Beuckmann, Carsten T.; Williams, S. Clay; Sinton, Christopher M.; Motoike, Toshiyuki; Richardson, James A.; Hammer, Robert E.; Garry, Mary G.; Yanagisawa, Masashi

2005-01-01

4

Autism-associated gene Dlgap2 mutant mice demonstrate exacerbated aggressive behaviors and orbitofrontal cortex deficits  

PubMed Central

Background As elegant structures designed for neural communication, synapses are the building bricks of our mental functions. Recently, many studies have pointed out that synaptic protein-associated mutations may lead to dysfunctions of social cognition. Dlgap2, which encodes one of the main components of scaffold proteins in postsynaptic density (PSD), has been addressed as a candidate gene in autism spectrum disorders. To elucidate the disturbance of synaptic balance arising from Dlgap2 loss-of-function in vivo, we thus generated Dlgap2 ?/? mice to investigate their phenotypes of synaptic function and social behaviors. Methods The creation of Dlgap2 ?/? mice was facilitated by the recombineering-based method, Cre-loxP system and serial backcross. Reversal learning in a water T-maze was used to determine repetitive behaviors. The three-chamber approach task, resident–intruder test and tube task were performed to characterize the social behaviors of mutant mice. Cortical synaptosomal fraction, Golgi-Cox staining, whole-cell patch electrophysiology and transmission electron microscopy were all applied to investigate the function and structure of synapses in the orbitofrontal cortex (OFC) of Dlgap2 ?/? mice. Results Dlgap2 ?/? mice displayed exacerbated aggressive behaviors in the resident–intruder task, and elevated social dominance in the tube test. In addition, Dlgap2 ?/? mice exhibited a clear reduction of receptors and scaffold proteins in cortical synapses. Dlgap2 ?/? mice also demonstrated lower spine density, decreased peak amplitude of miniature excitatory postsynaptic current and ultra-structural deficits of PSD in the OFC. Conclusions Our findings clearly demonstrate that Dlgap2 plays a vital role in social behaviors and proper synaptic functions of the OFC. Moreover, these results may provide valuable insights into the neuropathology of autism.

2014-01-01

5

Spontaneous Colitis in Muc2-Deficient Mice Reflects Clinical and Cellular Features of Active Ulcerative Colitis  

PubMed Central

Background The colonic mucus layer plays a critical role in intestinal homeostasis by limiting contact between luminal bacteria and the mucosal immune system. A defective mucus barrier in animal models allows bacterial contact with the intestinal epithelium and results in spontaneous colitis. A defective mucus barrier is also a key feature of active ulcerative colitis (UC). Alterations in the immune compartment due to intestinal bacterial breach in mice lacking the colon mucus barrier have not been characterized and correlated to active UC. Aims To characterize alterations in the immune compartment due to intestinal bacterial breach in Muc2?/? mice, which lack the colon mucus barrier, and correlate the findings to active UC. Methods Bacterial contact with colon epithelium and penetration into colon tissue was examined in Muc2?/? mice and colon biopsies from patients with active UC using fluorescence microscopy and qPCR. Neutrophils, lymphocytes, CD103+ dendritic cell subsets and macrophages in colon from Muc2?/? mice and biopsies from UC patients were quantitated by flow cytometry. Results Inflamed UC patients and Muc2?/? mice had bacteria in contact with the colon epithelium. Bacterial rRNA was present in colonic mucosa in humans and Muc2?/? mice and in the draining lymph nodes of mice. Inflamed Muc2?/? mice and UC patients had elevated colon neutrophils, T cells and macrophages while a reduced frequency of CD103+ DCs was present in the inflamed colon of both mice and humans. Conclusions The parallel features of the colon immune cell compartment in Muc2?/? mice and UC patients supports the usefulness of this model to understand the early phase of spontaneous colitis and will provide insight into novel strategies to treat UC.

Wenzel, Ulf A.; Magnusson, Maria K.; Rydstrom, Anna; Jonstrand, Caroline; Hengst, Julia; Johansson, Malin EV.; Velcich, Anna; Ohman, Lena; Strid, Hans; Sjovall, Henrik; Hansson, Gunnar C.; Wick, Mary Jo

2014-01-01

6

Leptin deficiency recapitulates the histological features of pulmonary arterial hypertension in mice  

PubMed Central

Leptin is a neuroendocrine peptide released by adipose tissue that enhances metabolism and acts on the hypothalamus to suppress appetite. Leptin also regulates aspects of cardiovascular function and low serum leptin has been associated with increased mortality in humans. We hypothesized that leptin deficiency alters the structure and function of the pulmonary vasculature. Methods: We examined two groups of C57BL/6 male mice aged 12 weeks: five ob/ob (B6.VLepob/ob) leptin-deficient and five wild type (WT) (C57BL/6) control mice. As expected, weight was significantly greater in ob/ob mice relative to WT mice [weight (g), Mean ± SD): ob/ob 52 ± 2.5 g, wild type 30 ± 2.5 g; p < 0.001]. The pulmonary vasculature of ob/ob mice and WT control animals was examined by histology, immunohistochemistry and immunofluorescence staining. Results: Pulmonary arterial wall thickness was significantly increased in ob/ob mice relative to WT littermates [median (interquartile range) distance in pixels: ob/ob 0.13 (0.05-0.18), wild type 0.03 (0.02-0.04); p = 0.001]. The ob/ob mice also exhibited significant right ventricular hypertrophy in comparison to control animals [RV thickness (Mean ± SD): ob/ob 0.75 ± 0.19, wild type; 0.58 ± 0.13 p < 0.001]. We observed substantial macrophage infiltration and abundant proliferation of myofibroblasts and fibroblasts in histological sections of pulmonary arterioles of ob/ob mice. In addition, we noted increased hyaluronan deposition, colocalizing with SMC-actin in the pulmonary vasculature of ob/ob mice relative to WT controls. Conclusions: The pulmonary pathology of leptin deficiency in ob/ob mice recapitulates many of the histological features of pulmonary vascular diseases, including pulmonary hypertension, suggesting that leptin deficiency is associated to the pathogenesis of pulmonary vascular disease.

Aytekin, Metin; Tonelli, Adriano R; Farver, Carol F; Feldstein, Ariel E; Dweik, Raed A

2014-01-01

7

Osteoprotegrin Knockout Mice Demonstrate Abnormal Remodeling of the Otic Capsule and Progressive Hearing Loss  

PubMed Central

Objectives The otic capsule, when compared with other bones in the body, is unique in that it undergoes no significant remodeling of bone after development. We previously demonstrated that osteoprotegerin (OPG), which inhibits formation and function of osteoclasts, is produced at high levels in the inner ear of normal mice and secreted into the peril-ymph from where it diffuses into the surrounding otic capsule bone through a lacunocanalicular system. To test our hypothesis that the high level of OPG may be important in the inhibition of otic capsule remodeling, we studied the light microscopic histology of the otic capsule in OPG knockout mice for evidence of abnormal remodeling of bone. We also tested the hearing in OPG knockout mice to determine whether OPG and its influence on surrounding bone is important for auditory function. Methods Temporal bone histopathology and pathophysiology were compared in homozygous OPG knockout mice and C57BL/6 (B6) mice, the background strain for the knockouts. Auditory function in age-matched animals from each group was evaluated at approximately 4-week intervals from 8 to 21 weeks using frequency-specific auditory brainstem responses (ABR) and distortion product otoacoustic emissions (DPOAE). After each of the last three evaluations, the cochleae from one mouse of each group were harvested, processed, and examined by light microscopy. Results Osteoprotegerin knockout mice demonstrated abnormal remodeling of bone within the otic capsule with multiple foci showing osteoclastic bone resorption and formation of new bone. Such changes were not seen in the age-matched B6 controls. The active bone remodeling process in the knockout animals showed many similarities to otosclerosis seen in human temporal bones. Over the time period that we monitored, auditory function was significantly and progressively compromised in the knockout animals relative to B6 controls. At the earliest age of test (8 wk), the loss was apparent as a mild, high-frequency reduction in sensitivity by ABR. In contrast, DPOAE losses in the knockouts were substantial even at 8 weeks, and by 21 weeks, these losses exceeded our equipment limits. Results of ABR testing showed hearing sensitivity changes in the animals of the background strain were confined largely to the high frequencies, whereas OPG knockouts demonstrated substantial low-frequency shifts in addition to those at high frequencies. Conclusions The histopathological and pathophysiological findings in OPG knockout mice support the hypothesis that OPG is important in the inhibition of bone remodeling within the otic capsule and the maintenance of normal auditory function. This mouse may provide a valuable animal model of human otosclerosis.

Zehnder, Andreas F.; Kristiansen, Arthur G.; Adams, Joe C.; Kujawa, Sharon G.; Merchant, Saumil N.; McKenna, Michael J.

2007-01-01

8

Targeted ANP32E Mutant Mice Do Not Demonstrate Obvious Movement Defects  

PubMed Central

Background The ANP32 family of proteins have been implicated in neuronal function through biochemical and cellular biology studies in neurons, as well as by recent behavioural studies of a gene-trapped loss-of-function mutation of Anp32e in mice, particularly with respect to fine motor function. A second targeted allele of the Anp32e, however, did not appear to demonstrate neurological phenotypes. Methodology/Principal Findings Using a stringently controlled cohort of ten-generation backcrossed, co-caged, sex-matched, littermate pairs, we assayed for potential motor defects in the targeted ANP32E-deficient mice. We found no phenotypic difference in any assays. Conclusion Since it is unlikely that the gene-trap is a more complete loss-of-function, our results suggest that ANP32E has no appreciable effect on motor functions and that genetic background differences most likely account for the gene-trap phenomena.

Wong, Peiyan; Leo, Vonny I.; Low, Meijun; Mak, Tak W.; Zhang, Xiaodong; Reilly, Patrick T.

2013-01-01

9

NPAS3 Demonstrates Features of a Tumor Suppressive Role in Driving the Progression of Astrocytomas  

PubMed Central

Malignant astrocytomas, the most common primary brain tumors, are predominantly fatal. Improved treatments will require a better understanding of the biological features of high-grade astrocytomas. To better understand the role of neuronal PAS 3 (NPAS3) in diseases in human beings, it was investigated as a candidate for astrocytomagenesis based on the presence of aberrant protein expression in greater than 70% of a human astrocytoma panel (n = 433) and most notably in surgically resected malignant lesions. In subsequent functional studies, it was concluded that NPAS3 exhibits features of a tumor-suppressor, which drives the progression of astrocytomas by modulating the cell cycle, proliferation, apoptosis, and cell migration/invasion and has a further influence on the viability of endothelial cells. Of clinical importance, absence of NPAS3 expression in glioblastomas was a significantly negative prognostic marker of survival. In addition, malignant astrocytomas lacking NPAS3 expression demonstrated loss of function mutations, which were associated with loss of heterozygosity. While overexpressed NPAS3 in malignant glioma cell lines significantly suppressed transformation, the converse decreased expression considerably induced more aggressive growth. In addition, knockdown NPAS3 expression in a human astrocyte cell line in concert with the human papillomavirus E6 and E7 oncogenes induced growth of malignant astrocytomas. In conclusion, NPAS3 drives the progression of human malignant astrocytomas as a tumor suppressor and is a negative prognostication marker for survival.

Moreira, Frederico; Kiehl, Tim-Rasmus; So, Kelvin; Ajeawung, Norbert F.; Honculada, Carmelita; Gould, Peter; Pieper, Russell O.; Kamnasaran, Deepak

2011-01-01

10

Ablation of the inflammatory enzyme myeloperoxidase mitigates features of Parkinson's disease in mice.  

PubMed

Parkinson's disease (PD) is characterized by a loss of ventral midbrain dopaminergic neurons, which can be modeled by the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Inflammatory oxidants have emerged as key contributors to PD- and MPTP-related neurodegeneration. Here, we show that myeloperoxidase (MPO), a key oxidant-producing enzyme during inflammation, is upregulated in the ventral midbrain of human PD and MPTP mice. We also show that ventral midbrain dopaminergic neurons of mutant mice deficient in MPO are more resistant to MPTP-induced cytotoxicity than their wild-type littermates. Supporting the oxidative damaging role of MPO in this PD model are the demonstrations that MPO-specific biomarkers 3-chlorotyrosine and hypochlorous acid-modified proteins increase in the brains of MPTP-injected mice. This study demonstrates that MPO participates in the MPTP neurotoxic process and suggests that inhibitors of MPO may provide a protective benefit in PD. PMID:16014720

Choi, Dong-Kug; Pennathur, Subramaniam; Perier, Celine; Tieu, Kim; Teismann, Peter; Wu, Du-Chu; Jackson-Lewis, Vernice; Vila, Miquel; Vonsattel, Jean-Paul; Heinecke, Jay W; Przedborski, Serge

2005-07-13

11

Non-Motor and Motor Features in LRRK2 Transgenic Mice  

PubMed Central

Background Non-motor symptoms are increasingly recognized as important features of Parkinson’s disease (PD). LRRK2 mutations are common causes of familial and sporadic PD. Non-motor features have not been yet comprehensively evaluated in LRRK2 transgenic mouse models. Objective Using a transgenic mouse model overexpressing the R1441G mutation of the human LRRK2 gene, we have investigated the longitudinal correlation between motor and non-motor symptoms and determined if specific non-motor phenotypes precede motor symptoms. Methodology We investigated the onset of motor and non-motor phenotypes on the LRRK2R1441G BAC transgenic mice and their littermate controls from 4 to 21 month-old using a battery of behavioral tests. The transgenic mutant mice displayed mild hypokinesia in the open field from 16 months old, with gastrointestinal dysfunctions beginning at 6 months old. Non-motor features such as depression and anxiety-like behaviors, sensorial functions (pain sensitivity and olfaction), and learning and memory abilities in the passive avoidance test were similar in the transgenic animals compared to littermate controls. Conclusions LRRK2R1441G BAC transgenic mice displayed gastrointestinal dysfunction at an early stage but did not have abnormalities in fine behaviors, olfaction, pain sensitivity, mood disorders and learning and memory compared to non-transgenic littermate controls. The observations on olfaction and gastrointestinal dysfunction in this model validate findings in human carriers. These mice did recapitulate mild Parkinsonian motor features at late stages but compensatory mechanisms modulating the progression of PD in these models should be further evaluated.

Bichler, Zoe; Lim, Han Chi; Zeng, Li; Tan, Eng King

2013-01-01

12

Functional MRI demonstrates pain perception in hand osteoarthritis has features of central pain processing  

PubMed Central

Background Hand osteoarthritis (HOA) is typified by pain and reduced function. We hypothesised that people with HOA have enhanced sensitivity and activation of peripheral nociceptors in the hand, thereby potentiating chronic pain. In our study we aimed to assess if central sensitisation mediates pain perception in osteoarthritis of the hand. Methods Participants with proximal and distal interphalangeal joint (PIP/DIP) HOA and non-OA controls were recruited. Clinical pain scores using the visual analogue scale (VAS) were recorded before and after performing a painful hand task. Central pain processing was evaluated with functional brain neuroimaging (fMRI) using a finger flexion-extension (FFE) task performed over 3 minutes. Data was analysed with FMRIB software (www.fmrib.ox.ac.uk/fsl). Group mean activation of functional MRI signal between hand osteoarthritis and control non-arthritic participants was compared. Results Our group of hand OA participants reported high pain levels compared with non-arthritic controls as demonstrated by the mean VAS in hand OA participants of 59.31± 8.19 mm compared to 4.00 ± 1.89 mm in controls (p < 0.0001), despite all participants reporting analgesic use. Functional MRI analysis showed increased activation in the thalamus, cingulate, frontal and somatosensory cortex in the hand OA group but not in controls (thresholded at p < 0.05). Regions of activation were mapped to Brodmann areas 3, 4, 6, 9, 13, 22, 24 and 44. Activated regions found in our study are recognised higher brain pain processing centres implicated in central sensitisation. Conclusions People with hand osteoarthritis demonstrated features of central sensitisation that was evident after a finger flexion-extension task using functional MRI. Functional MRI is a useful biomarker in detecting pain in hand osteoarthritis and could be used in future hand osteoarthritis pain studies to evaluate pain modulation strategies.

Sofat, Nidhi; Smee, Cori; Hermansson, Monika; Howard, Matthew; Baker, Emma H; Howe, Franklyn A; Barrick, Thomas R

2013-01-01

13

Intact memory in TGF-?1 transgenic mice featuring chronic cerebrovascular deficit: recovery with pioglitazone  

PubMed Central

The roles of chronic brain hypoperfusion and transforming growth factor-beta 1 (TGF-?1) in Alzheimer's disease (AD) are unresolved. We investigated the interplay between TGF-?1, cerebrovascular function, and cognition using transgenic TGF mice featuring astrocytic TGF-?1 overexpression. We further assessed the impact of short, late therapy in elderly animals with the antioxidant N-acetyl--cysteine (NAC) or the peroxisome proliferator-activated receptor-? agonist pioglitazone. The latter was also administered to pups as a prophylactic 1-year treatment. Elderly TGF mice featured cerebrovascular dysfunction that was not remedied with NAC. In contrast, pioglitazone prevented or reversed this deficit, and rescued the impaired neurovascular coupling response to whisker stimulation, although it failed to normalize the vascular structure. In aged TGF mice, neuronal and cognitive indices—the stimulus-evoked neurometabolic response, cortical cholinergic innervation, and spatial memory in the Morris water maze—were intact. Our findings show that impaired brain hemodynamics and cerebrovascular function are not accompanied by memory impairment in this model. Conceivably in AD, they constitute aggravating factors against a background of aging and underlying pathology. Our data further highlight the ability of pioglitazone to protect the cerebrovasculature marked by TGF-?1 increase, aging, fibrosis, and antioxidant resistance, thus of high relevance for AD patients.

Nicolakakis, Nektaria; Aboulkassim, Tahar; Aliaga, Antonio; Tong, Xin-Kang; Rosa-Neto, Pedro; Hamel, Edith

2011-01-01

14

Intact memory in TGF-?1 transgenic mice featuring chronic cerebrovascular deficit: recovery with pioglitazone.  

PubMed

The roles of chronic brain hypoperfusion and transforming growth factor-beta 1 (TGF-?1) in Alzheimer's disease (AD) are unresolved. We investigated the interplay between TGF-?1, cerebrovascular function, and cognition using transgenic TGF mice featuring astrocytic TGF-?1 overexpression. We further assessed the impact of short, late therapy in elderly animals with the antioxidant N-acetyl-L-cysteine (NAC) or the peroxisome proliferator-activated receptor-? agonist pioglitazone. The latter was also administered to pups as a prophylactic 1-year treatment. Elderly TGF mice featured cerebrovascular dysfunction that was not remedied with NAC. In contrast, pioglitazone prevented or reversed this deficit, and rescued the impaired neurovascular coupling response to whisker stimulation, although it failed to normalize the vascular structure. In aged TGF mice, neuronal and cognitive indices--the stimulus-evoked neurometabolic response, cortical cholinergic innervation, and spatial memory in the Morris water maze--were intact. Our findings show that impaired brain hemodynamics and cerebrovascular function are not accompanied by memory impairment in this model. Conceivably in AD, they constitute aggravating factors against a background of aging and underlying pathology. Our data further highlight the ability of pioglitazone to protect the cerebrovasculature marked by TGF-?1 increase, aging, fibrosis, and antioxidant resistance, thus of high relevance for AD patients. PMID:20571524

Nicolakakis, Nektaria; Aboulkassim, Tahar; Aliaga, Antonio; Tong, Xin-Kang; Rosa-Neto, Pedro; Hamel, Edith

2011-01-01

15

GIP-Overexpressing Mice Demonstrate Reduced Diet-Induced Obesity and Steatosis, and Improved Glucose Homeostasis  

PubMed Central

Glucose-dependent insulinotropic polypeptide (GIP) is a gastrointestinal hormone that potentiates glucose-stimulated insulin secretion during a meal. Since GIP has also been shown to exert ?-cell prosurvival and adipocyte lipogenic effects in rodents, both GIP receptor agonists and antagonists have been considered as potential therapeutics in type 2 diabetes (T2DM). In the present study, we tested the hypothesis that chronically elevating GIP levels in a transgenic (Tg) mouse model would increase adipose tissue expansion and exert beneficial effects on glucose homeostasis. In contrast, although GIP Tg mice demonstrated enhanced ?-cell function, resulting in improved glucose tolerance and insulin sensitivity, they exhibited reduced diet-induced obesity. Adipose tissue macrophage infiltration and hepatic steatosis were both greatly reduced, and a number of genes involved in lipid metabolism/inflammatory signaling pathways were found to be down-regulated. Reduced adiposity in GIP Tg mice was associated with decreased energy intake, involving overexpression of hypothalamic GIP. Together, these studies suggest that, in the context of over-nutrition, transgenic GIP overexpression has the potential to improve hepatic and adipocyte function as well as glucose homeostasis.

Kim, Su-Jin; Nian, Cuilan; Karunakaran, Subashini; Clee, Susanne M.; Isales, Carlos M.; McIntosh, Christopher H. S.

2012-01-01

16

Resistance to change and vulnerability to stress: Autistic-like features of GAP43 deficient mice  

PubMed Central

There is an urgent need for animal models of autism spectrum disorder (ASD) to understand the underlying pathology and facilitate development and testing of new treatments. The synaptic growth-associated protein-43 (GAP43) has recently been identified as an autism candidate gene of interest. Our previous studies show many brain abnormalities in mice lacking one allele for GAP43 (GAP43 (+/?)) that are consistent with the disordered connectivity theory of ASD. Thus, we hypothesized that GAP43 (+/?) mice would demonstrate at least some autistic-like behaviors. We found that GAP43 (+/?) mice, relative to wild-type (+/+) littermates, displayed resistance to change, consistent with one of the diagnostic critera for ASD. GAP43 (+/?) mice also displayed stress-induced behavioral withdrawal and anxiety, as seen in many autistic individuals. In addition, both GAP43 (+/?) mice and (+/+) littermates demonstrated low social approach and lack of preference for social novelty, consistent with another diagnostic criterion for ASD. This low sociability is likely due to the mixed C57BL/6J 129S3/SvImJ background. We conclude that GAP43 deficiency leads to the development of a subset of autistic-like behaviors. Since these behaviors occur in a mouse that displays disordered connectivity, we propose that future anatomical and functional studies in this mouse may help uncover underlying mechanisms for these specific behaviors. Strain-specific low sociability may be advantageous in these studies, creating a more autistic-like environment for study of the GAP43-mediated deficits of resistance to change and vulnerability to stress.

Zaccaria, Kimberly J; Lagace, Diane C; Eisch, Amelia J; McCasland, James S

2010-01-01

17

Epidermal-specific defect of GPI anchor in Pig-a null mice results in Harlequin ichthyosis-like features.  

PubMed

We previously demonstrated that the epidermal-specific glycosylphosphatidylinositol (GPI)-anchor-deficient mice, generated by Pig-a gene disruption (Pig-a null mice), exhibited wrinkled and dry skin with hyperkeratosis and abnormal differentiation, and they died within a few days after birth. Here, we investigated the basis for the early demise of these animals, and the potential role of epidermal structural and biochemical abnormalities. The rapid demise of these animals was associated with both diminished epidermal permeability barrier function and decreased stratum corneum (SC) water content. The barrier abnormality could be attributed abnormal internal contents of lamellar bodies, with a downstream failure to generate normal extracellular lamellar bilayers in the SC. Moreover, processing profilaggrin to its monomeric form was impaired in Pig-a null mouse epidermis, while levels of the differentiation-specific proteins, involucrin, loricrin and profilaggrin were normal. Failure of filaggrin processing was accompanied by decreased activity of protein phosphatase 2A, an enzyme involved in profilaggrin to filaggrin processing. Thus, these studies demonstrate a critical role for GPI anchor and GPI-anchored proteins in divergent arms of epidermal terminal differentiation. While the permeability barrier abnormality can be attributed to defects in the lamellar body secretory system, the hydration abnormality is, in part, due to lack of availability of filaggrin-derived proteolytic products. Finally, since the dual abnormalities in the lamellar body secretory system and filaggrin processing resemble two key features of human Harlequin ichthyosis, Pig-a null mice could provide an appropriate analog for further studies of this disease. PMID:15304084

Hara-Chikuma, Mariko; Takeda, Junji; Tarutani, Masahito; Uchida, Yoshikazu; Holleran, Walter M; Endo, Yoko; Elias, Peter M; Inoue, Shintaro

2004-09-01

18

Monoamine oxidase A and A/B knockout mice display autistic-like features  

PubMed Central

Converging lines of evidence show that a sizable subset of autism-spectrum disorders (ASDs) is characterized by increased blood levels of serotonin (5-hydroxytryptamine, 5-HT), yet the mechanistic link between these two phenomena remains unclear. The enzymatic degradation of brain 5-HT is mainly mediated by monoamine oxidase (MAO)A and, in the absence of this enzyme, by its cognate isoenzyme MAOB. MAOA and A/B knockout (KO) mice display high 5-HT levels, particularly during early developmental stages. Here we show that both mutant lines exhibit numerous behavioural hallmarks of ASDs, such as social and communication impairments, perseverative and stereotypical responses, behavioural inflexibility, as well as subtle tactile and motor deficits. Furthermore, both MAOA and A/B KO mice displayed neuropathological alterations reminiscent of typical ASD features, including reduced thickness of the corpus callosum, increased dendritic arborization of pyramidal neurons in the prefrontal cortex and disrupted microarchitecture of the cerebellum. The severity of repetitive responses and neuropathological aberrances was generally greater in MAOA/B KO animals. These findings suggest that the neurochemical imbalances induced by MAOAdeficiency (either by itself or in conjunction with lack of MAOB) may result in an array of abnormalities similar to those observed in ASDs. Thus, MAOA and A/B KO mice may afford valuable models to help elucidate the neurobiological bases of these disorders and related neurodevelopmental problems.

Bortolato, Marco; Godar, Sean C.; Alzghoul, Loai; Zhang, Junlin; Darling, Ryan D.; Simpson, Kimberly L.; Bini, Valentina; Chen, Kevin; Wellman, Cara L.; Lin, Rick C. S.; Shih, Jean C.

2012-01-01

19

Monoamine oxidase A and A/B knockout mice display autistic-like features.  

PubMed

Converging lines of evidence show that a sizable subset of autism-spectrum disorders (ASDs) is characterized by increased blood levels of serotonin (5-hydroxytryptamine, 5-HT), yet the mechanistic link between these two phenomena remains unclear. The enzymatic degradation of brain 5-HT is mainly mediated by monoamine oxidase (MAO)A and, in the absence of this enzyme, by its cognate isoenzyme MAOB. MAOA and A/B knockout (KO) mice display high 5-HT levels, particularly during early developmental stages. Here we show that both mutant lines exhibit numerous behavioural hallmarks of ASDs, such as social and communication impairments, perseverative and stereotypical responses, behavioural inflexibility, as well as subtle tactile and motor deficits. Furthermore, both MAOA and A/B KO mice displayed neuropathological alterations reminiscent of typical ASD features, including reduced thickness of the corpus callosum, increased dendritic arborization of pyramidal neurons in the prefrontal cortex and disrupted microarchitecture of the cerebellum. The severity of repetitive responses and neuropathological aberrances was generally greater in MAOA/B KO animals. These findings suggest that the neurochemical imbalances induced by MAOA deficiency (either by itself or in conjunction with lack of MAOB) may result in an array of abnormalities similar to those observed in ASDs. Thus, MAOA and A/B KO mice may afford valuable models to help elucidate the neurobiological bases of these disorders and related neurodevelopmental problems. PMID:22850464

Bortolato, Marco; Godar, Sean C; Alzghoul, Loai; Zhang, Junlin; Darling, Ryan D; Simpson, Kimberly L; Bini, Valentina; Chen, Kevin; Wellman, Cara L; Lin, Rick C S; Shih, Jean C

2013-05-01

20

Senescence induced by RECQL4 dysfunction contributes to Rothmund-Thomson syndrome features in mice.  

PubMed

Cellular senescence refers to irreversible growth arrest of primary eukaryotic cells, a process thought to contribute to aging-related degeneration and disease. Deficiency of RecQ helicase RECQL4 leads to Rothmund-Thomson syndrome (RTS), and we have investigated whether senescence is involved using cellular approaches and a mouse model. We first systematically investigated whether depletion of RECQL4 and the other four human RecQ helicases, BLM, WRN, RECQL1 and RECQL5, impacts the proliferative potential of human primary fibroblasts. BLM-, WRN- and RECQL4-depleted cells display increased staining of senescence-associated ?-galactosidase (SA-?-gal), higher expression of p16(INK4a) or/and p21(WAF1) and accumulated persistent DNA damage foci. These features were less frequent in RECQL1- and RECQL5-depleted cells. We have mapped the region in RECQL4 that prevents cellular senescence to its N-terminal region and helicase domain. We further investigated senescence features in an RTS mouse model, Recql4-deficient mice (Recql4(HD)). Tail fibroblasts from Recql4(HD) showed increased SA-?-gal staining and increased DNA damage foci. We also identified sparser tail hair and fewer blood cells in Recql4(HD) mice accompanied with increased senescence in tail hair follicles and in bone marrow cells. In conclusion, dysfunction of RECQL4 increases DNA damage and triggers premature senescence in both human and mouse cells, which may contribute to symptoms in RTS patients. PMID:24832598

Lu, H; Fang, E F; Sykora, P; Kulikowicz, T; Zhang, Y; Becker, K G; Croteau, D L; Bohr, V A

2014-01-01

21

Senescence induced by RECQL4 dysfunction contributes to Rothmund-Thomson syndrome features in mice  

PubMed Central

Cellular senescence refers to irreversible growth arrest of primary eukaryotic cells, a process thought to contribute to aging-related degeneration and disease. Deficiency of RecQ helicase RECQL4 leads to Rothmund–Thomson syndrome (RTS), and we have investigated whether senescence is involved using cellular approaches and a mouse model. We first systematically investigated whether depletion of RECQL4 and the other four human RecQ helicases, BLM, WRN, RECQL1 and RECQL5, impacts the proliferative potential of human primary fibroblasts. BLM-, WRN- and RECQL4-depleted cells display increased staining of senescence-associated ?-galactosidase (SA-?-gal), higher expression of p16INK4a or/and p21WAF1 and accumulated persistent DNA damage foci. These features were less frequent in RECQL1- and RECQL5-depleted cells. We have mapped the region in RECQL4 that prevents cellular senescence to its N-terminal region and helicase domain. We further investigated senescence features in an RTS mouse model, Recql4-deficient mice (Recql4HD). Tail fibroblasts from Recql4HD showed increased SA-?-gal staining and increased DNA damage foci. We also identified sparser tail hair and fewer blood cells in Recql4HD mice accompanied with increased senescence in tail hair follicles and in bone marrow cells. In conclusion, dysfunction of RECQL4 increases DNA damage and triggers premature senescence in both human and mouse cells, which may contribute to symptoms in RTS patients.

Lu, H; Fang, E F; Sykora, P; Kulikowicz, T; Zhang, Y; Becker, K G; Croteau, D L; Bohr, V A

2014-01-01

22

Integrin ?1/Akita double knockout mice on a Balb/c background develop advanced features of human diabetic nephropathy  

PubMed Central

Animal models that mimic human diabetic nephropathy are useful to identify key factors in pathogenesis of this disease as well as the development of new therapies. Several mouse models of diabetes have features of human diabetic nephropathy, yet none of these completely fulfill the Animal Models of Diabetes Complications Consortium criteria and completely reproduce pathological and functional features of the human disease. The Akita mouse carries a mutation in the insulin 2 gene and, to date, only survive as heterozygotes that develop spontaneous type 1 diabetes. Here we show that Akita mice with mutation of both insulin 2 alleles (Akita knockout (KO)) survive if crossed onto the Balb/c background. These mice develop hyperglycemia, more severe albuminuria and mesangial sclerosis compared to heterozygous mice on the same genetic background. Interestingly, crossing these AkitaKO mice with integrin ?1KO mice, a model of exacerbated glomerulosclerosis after injury and also on the Balb/c background, resulted in a 16-fold increase in albuminuria, significant mesangial matrix expansion, nodular and diffuse glomerulosclerosis, and a 2-fold increase in glomerular basement membrane thickening when compared to non-diabetic mice. Moreover a significant decline in glomerular filtration was evident in the ?1KOAkitaKO mice at 6 months of age. Thus, the integrin ?1KOAkitaKO Balb/c mouse represents a promising model presenting with most features of human diabetic nephropathy.

Yu, Ling; Su, Yan; Paueksakon, Paisit; Cheng, Huifang; Chen, Xiwu; Wang, Hongtao; Harris, Raymond C.; Zent, Roy; Pozzi, Ambra

2012-01-01

23

Fabry Disease: Preclinical Studies Demonstrate the Effectiveness of ?-Galactosidase A Replacement in Enzyme-Deficient Mice  

PubMed Central

Preclinical studies of enzyme-replacement therapy for Fabry disease (deficient ?-galactosidase A [?-Gal A] activity) were performed in ?-Gal A–deficient mice. The pharmacokinetics and biodistributions were determined for four recombinant human ?-Gal A glycoforms, which differed in sialic acid and mannose-6-phosphate content. The plasma half-lives of the glycoforms were ?2–5 min, with the more sialylated glycoforms circulating longer. After intravenous doses of 1 or 10 mg/kg body weight were administered, each glycoform was primarily recovered in the liver, with detectable activity in other tissues but not in the brain. Normal or greater activity levels were reconstituted in various tissues after repeated doses (10 mg/kg every other day for eight doses) of the highly sialylated AGA-1 glycoform; 4 d later, enzyme activity was retained in the liver and spleen at levels that were, respectively, 30% and 10% of that recovered 1 h postinjection. Importantly, the globotriaosylceramide (GL-3) substrate was depleted in various tissues and plasma in a dose-dependent manner. A single or repeated doses (every 48 h for eight doses) of AGA-1 at 0.3–10.0 mg/kg cleared hepatic GL-3, whereas higher doses were required for depletion of GL-3 in other tissues. After a single dose of 3 mg/kg, hepatic GL-3 was cleared for ?4 wk, whereas cardiac and splenic GL-3 reaccumulated at 3 wk to ?30% and ?10% of pretreatment levels, respectively. Ultrastructural studies demonstrated reduced GL-3 storage posttreatment. These preclinical animal studies demonstrate the dose-dependent clearance of tissue and plasma GL-3 by administered ?-Gal A, thereby providing the in vivo rationale—and the critical pharmacokinetic and pharmacodynamic data—for the design of enzyme-replacement trials in patients with Fabry disease.

Ioannou, Yiannis A.; Zeidner, Ken M.; Gordon, Ronald E.; Desnick, Robert J.

2001-01-01

24

The SGLT2 inhibitor empagliflozin ameliorates early features of diabetic nephropathy in BTBR ob/ob type 2 diabetic mice with and without hypertension.  

PubMed

Diabetic nephropathy is the leading cause of end-stage renal disease in humans in the Western world. The recent development of Na(+)-glucose cotransporter 2 (SGLT2) inhibitors offers a new antidiabetic therapy via enhanced glucose excretion. Whether this strategy exerts beneficial effects on the development of type 2 diabetic nephropathy is still largely unclear. We investigated the effects of the specific SGLT2 inhibitor empagliflozin in BTBR.Cg-Lep/WiscJ (BTBR ob/ob) mice, which spontaneously develop type 2 diabetic nephropathy. In the first experiment, BTBR ob/ob mice received either a diet containing 300 ppm empagliflozin or equicaloric placebo chow for 12 wk. In the second experiment, BTBR ob/ob mice received 1 ?g·kg body wt(-1)·day(-1) ANG II to induce arterial hypertension and were separated into the same two diet groups for 6 wk. In both experiments, empagliflozin treatment enhanced glucosuria, thereby lowering blood glucose. Independently of hypertension, empagliflozin reduced albuminuria in diabetic mice. However, empagliflozin treatment affected diabetes-related glomerular hypertrophy, markers of renal inflammation, and mesangial matrix expansion only in BTBR ob/ob mice without hypertension. In summary, empagliflozin demonstrated significant antihyperglycemic effects, differentially ameliorating early features of diabetic nephropathy in BTBR ob/ob mice with and without hypertension. PMID:24944269

Gembardt, Florian; Bartaun, Christoph; Jarzebska, Natalia; Mayoux, Eric; Todorov, Vladimir T; Hohenstein, Bernd; Hugo, Christian

2014-08-01

25

Unusual Features in an Adult Pancreatic Hemangioma: CT and MRI Demonstration  

PubMed Central

Hemangiomas in the pancreas are very rare and only a few cases in adulthood have been reported in the literature. We describe a case of pancreatic hemangiomas in an adult with unique imaging findings. A 23-year-old woman visited the hospital for an incidentally detected pancreatic mass. CT and MRI revealed a multilocular cyst with fluid-fluid levels and no obvious enhancement. The patient underwent surgery and the mass was confirmed as a pancreatic hemangioma. The radiological features and differential diagnosis of this rare lesion are discussed.

Wu, Mei

2013-01-01

26

Compared with DBA/2J mice, C57BL/6J mice demonstrate greater preference for saccharin and less avoidance of a cocaine-paired saccharin cue  

PubMed Central

Rats avoid intake of a saccharin cue when paired with a drug of abuse. While this is true for most subjects, the degree of avoidance of the drug-paired cue depends upon many factors including an individual rat’s preference for rewards. That said, the direction of this effect is complex. For example, reward-preferring Lewis rats exhibit greater cocaine-induced avoidance of a saccharin cue relative to Fischer 344 rats; while reward-preferring mice that over express ?FosB (NSE-tTA x TetOp-?FosB) exhibit less avoidance of the drug-paired taste cue compared to controls. The aim here was to use two strains of commonly used mice, C57BL/6J and DBA/2J, to determine whether known differences in sensitivity to rewards will facilitate or attenuate drug-induced suppression of intake of a drug-paired taste cue. The results of Experiment 1 demonstrate that C57BL/6J mice, compared with DBA/2J mice, exhibit attenuated suppression of saccharin intake when it is paired with cocaine. The results of Experiment 2 demonstrate that strain differences in impulsivity are not likely to account for these differences. It is proposed that, while the C57BL/6J mice typically are more responsive to drug, they also are more responsive to natural rewards (in this case saccharin), and the stronger preference for saccharin serves to militate against drug.

Freet, Christopher S.; Arndt, Amanda; Grigson, Patricia S.

2014-01-01

27

Hip14l-deficient mice develop neuropathological and behavioural features of Huntington disease.  

PubMed

Palmitoylation, the dynamic post-translational addition of the lipid, palmitate, to proteins by Asp-His-His-Cys-containing palmitoyl acyltransferase (PAT) enzymes, modulates protein function and localization and plays a key role in the nervous system. Huntingtin-interacting protein 14 (HIP14), a well-characterized neuronal PAT, has been implicated in the pathogenesis of Huntington disease (HD), a fatal neurodegenerative disease associated with motor, psychiatric and cognitive symptoms, caused by a CAG expansion in the huntingtin gene (HTT). Mice deficient for Hip14 expression develop neuropathological and behavioural features similar to HD, and the catalytic activity of HIP14 is impaired in HD mice, most likely due to the reduced interaction of HIP14 with HTT. Huntingtin-interacting protein 14-like (HIP14L) is a paralog of HIP14, with identical domain structure. Together, HIP14 and HIP14L are the major PATs for HTT. Here, we report the characterization of a Hip14l-deficient mouse model, which develops adult-onset, widespread and progressive neuropathology accompanied by early motor deficits in climbing, impaired motor learning and reduced palmitoylation of a novel HIP14L substrate: SNAP25. Although the phenotype resembles that of the Hip14(-/-) mice, a more progressive phenotype, similar to that of the YAC128 transgenic mouse model of HD, is observed. In addition, HIP14L interacts less with mutant HTT than the wild-type protein, suggesting that reduced HIP14L-dependent palmitoylation of neuronal substrates may contribute to the pathogenesis of HD. Thus, both HIP14 and HIP14L may be dysfunctional in the disease. PMID:23077216

Sutton, Liza M; Sanders, Shaun S; Butland, Stefanie L; Singaraja, Roshni R; Franciosi, Sonia; Southwell, Amber L; Doty, Crystal N; Schmidt, Mandi E; Mui, Katherine K N; Kovalik, Vlad; Young, Fiona B; Zhang, Weining; Hayden, Michael R

2013-02-01

28

Software defined networking (SDN) over space division multiplexing (SDM) optical networks: features, benefits and experimental demonstration.  

PubMed

We present results from the first demonstration of a fully integrated SDN-controlled bandwidth-flexible and programmable SDM optical network utilizing sliceable self-homodyne spatial superchannels to support dynamic bandwidth and QoT provisioning, infrastructure slicing and isolation. Results show that SDN is a suitable control plane solution for the high-capacity flexible SDM network. It is able to provision end-to-end bandwidth and QoT requests according to user requirements, considering the unique characteristics of the underlying SDM infrastructure. PMID:24663655

Amaya, N; Yan, S; Channegowda, M; Rofoee, B R; Shu, Y; Rashidi, M; Ou, Y; Hugues-Salas, E; Zervas, G; Nejabati, R; Simeonidou, D; Puttnam, B J; Klaus, W; Sakaguchi, J; Miyazawa, T; Awaji, Y; Harai, H; Wada, N

2014-02-10

29

DHCR24 gene knockout mice demonstrate lethal dermopathy with differentiation and maturation defects in the epidermis.  

PubMed

Desmosterolosis is an autosomal recessive disorder due to mutations in the 3beta-hydroxysterol-Delta24 reductase (DHCR24) gene that encodes an enzyme catalyzing the conversion of desmosterol to cholesterol. To date, only two patients have been reported with severe developmental defects including craniofacial abnormalities and limb malformations. We employed mice with targeted disruption of DHCR24 to understand the pathophysiology of desmosterolosis. All DHCR24-/- mice died within a few hours after birth. Their skin was wrinkleless and less pliant, leading to restricted movement and inability to suck (empty stomach). DHCR24 gene was expressed abundantly in the epidermis of control but not of DHCR24-/- mice. Accordingly, cholesterol was not detected whereas desmosterol was abundant in the epidermis of DHCR24-/- mice. Skin histology revealed thickened epidermis with few and smaller keratohyaline granules. Aberrant expression of keratins such as keratins 6 and 14 suggested hyperproliferative hyperkeratosis with undifferentiated keratinocytes throughout the epidermis. Altered expression of filaggrin, loricrin, and involcrin were also observed in the epidermis of DHCR24-/-. These findings suggested impaired skin barrier function. Indeed, increased trans-epidermal water loss and permeability of Lucifer yellow were observed in DHCR24-/- mice. DHCR24 thus plays crucial role for skin development and its proper function. PMID:16410790

Mirza, Rusella; Hayasaka, Shizu; Takagishi, Yoshiko; Kambe, Fukushi; Ohmori, Sachiko; Maki, Kazuko; Yamamoto, Michiyo; Murakami, Kohji; Kaji, Takahide; Zadworny, David; Murata, Yoshiharu; Seo, Hisao

2006-03-01

30

Spondyloarthropathy in Progressive Ankylosis Mice: Ultrastructural Features of the Intervertebral Disk  

Microsoft Academic Search

Progressive ankylosis mice (ank\\/ank) spontaneously develop a joint disorder characterized by calcium hydroxyapatite deposition and bony ankylosis of the joints of the axial and the appendicular skeleton. Mice in this study were used to determine the extent of mineralization of the intervertebral disks and to determine their suitability as a model for ankylosing spondyloarthropathies. Intervertebral disks taken from affected mice

H. W. Sampson; R. W. Davis; D. C. Dufner

1991-01-01

31

Dietary inorganic nitrate reverses features of metabolic syndrome in endothelial nitric oxide synthase-deficient mice.  

PubMed

The metabolic syndrome is a clustering of risk factors of metabolic origin that increase the risk for cardiovascular disease and type 2 diabetes. A proposed central event in metabolic syndrome is a decrease in the amount of bioavailable nitric oxide (NO) from endothelial NO synthase (eNOS). Recently, an alternative pathway for NO formation in mammals was described where inorganic nitrate, a supposedly inert NO oxidation product and unwanted dietary constituent, is serially reduced to nitrite and then NO and other bioactive nitrogen oxides. Here we show that several features of metabolic syndrome that develop in eNOS-deficient mice can be reversed by dietary supplementation with sodium nitrate, in amounts similar to those derived from eNOS under normal conditions. In humans, this dose corresponds to a rich intake of vegetables, the dominant dietary nitrate source. Nitrate administration increased tissue and plasma levels of bioactive nitrogen oxides. Moreover, chronic nitrate treatment reduced visceral fat accumulation and circulating levels of triglycerides and reversed the prediabetic phenotype in these animals. In rats, chronic nitrate treatment reduced blood pressure and this effect was also present during NOS inhibition. Our results show that dietary nitrate fuels a nitrate-nitrite-NO pathway that can partly compensate for disturbances in endogenous NO generation from eNOS. These findings may have implications for novel nutrition-based preventive and therapeutic strategies against cardiovascular disease and type 2 diabetes. PMID:20876122

Carlström, Mattias; Larsen, Filip J; Nyström, Thomas; Hezel, Michael; Borniquel, Sara; Weitzberg, Eddie; Lundberg, Jon O

2010-10-12

32

Dietary inorganic nitrate reverses features of metabolic syndrome in endothelial nitric oxide synthase-deficient mice  

PubMed Central

The metabolic syndrome is a clustering of risk factors of metabolic origin that increase the risk for cardiovascular disease and type 2 diabetes. A proposed central event in metabolic syndrome is a decrease in the amount of bioavailable nitric oxide (NO) from endothelial NO synthase (eNOS). Recently, an alternative pathway for NO formation in mammals was described where inorganic nitrate, a supposedly inert NO oxidation product and unwanted dietary constituent, is serially reduced to nitrite and then NO and other bioactive nitrogen oxides. Here we show that several features of metabolic syndrome that develop in eNOS-deficient mice can be reversed by dietary supplementation with sodium nitrate, in amounts similar to those derived from eNOS under normal conditions. In humans, this dose corresponds to a rich intake of vegetables, the dominant dietary nitrate source. Nitrate administration increased tissue and plasma levels of bioactive nitrogen oxides. Moreover, chronic nitrate treatment reduced visceral fat accumulation and circulating levels of triglycerides and reversed the prediabetic phenotype in these animals. In rats, chronic nitrate treatment reduced blood pressure and this effect was also present during NOS inhibition. Our results show that dietary nitrate fuels a nitrate–nitrite–NO pathway that can partly compensate for disturbances in endogenous NO generation from eNOS. These findings may have implications for novel nutrition-based preventive and therapeutic strategies against cardiovascular disease and type 2 diabetes.

Carlstrom, Mattias; Larsen, Filip J.; Nystrom, Thomas; Hezel, Michael; Borniquel, Sara; Weitzberg, Eddie; Lundberg, Jon O.

2010-01-01

33

A high-fat diet and multiple administration of carbon tetrachloride induces liver injury and pathological features associated with non-alcoholic steatohepatitis in mice.  

PubMed

The aim of the present study was to establish a progressive steatohepatitis mouse model because few reported animal models of non-alcoholic steatohepatitis (NASH) show the progression from fatty liver to steatohepatitis. C57BL/6N mice were fed a high-fat diet (HFD) to develop obesity and were either administered carbon tetrachloride (CCl4 ) eight times (0.05 mL/kg, s.c., once, followed by 0.1 mL/kg, s.c., seven times) or not. Serum parameters and hepatic histopathology were examined. In a separate experiment, CCl4 was administered subcutaneously from 0 to eight times to HFD-fed obese mice to investigate progressive changes. Markers of oxidative stress, inflammation and apoptosis, as well as histopathological changes in the liver, were analysed. The HFD-fed obese mice showed fatty liver but not steatohepatitis. In contrast, HFD-fed mice administered CCl4 eight times showed histopathological features of steatohepatitis (fatty liver, inflammation, hepatocellular ballooning and fibrosis) and increased serum alanine aminotransferase levels. However, the multiple administration of CCl4 to obese mice reduced the ratio of reduced glutathione to oxidized glutathione, superoxide dismutase activity and mitochondrial DNA copy number, leading to the development of chronic oxidative stress, increased numbers of apoptotic cells and increased levels of both tumour necrosis factor-? and transforming growth factor-? mRNA. The resulting inflammation led to increased hydroxyproline content in the liver and fibrosis. The present study demonstrates that multiple administration of CCl4 to HFD-fed obese mice induces chronic oxidative stress that triggers inflammation and apoptosis and leads to the development of fibrosis in the liver, resulting in progression from fatty liver to steatohepatitis. This murine model will be useful in the research of hepatic disorders. PMID:23611112

Kubota, Norihiro; Kado, Shoichi; Kano, Mitsuyoshi; Masuoka, Norie; Nagata, Yuriko; Kobayashi, Toshihide; Miyazaki, Kouji; Ishikawa, Fumiyasu

2013-07-01

34

Knock-In Reporter Mice Demonstrate that DNA Repair by Non-homologous End Joining Declines with Age  

PubMed Central

Accumulation of genome rearrangements is a characteristic of aged tissues. Since genome rearrangements result from faulty repair of DNA double strand breaks (DSBs), we hypothesized that DNA DSB repair becomes less efficient with age. The Non-Homologous End Joining (NHEJ) pathway repairs a majority of DSBs in vertebrates. To examine age-associated changes in NHEJ, we have generated an R26NHEJ mouse model in which a GFP-based NHEJ reporter cassette is knocked-in to the ROSA26 locus. In this model, NHEJ repair of DSBs generated by the site-specific endonuclease, I-SceI, reconstitutes a functional GFP gene. In this system NHEJ efficiency can be compared across tissues of the same mouse and in mice of different age. Using R26NHEJ mice, we found that NHEJ efficiency was higher in the skin, lung, and kidney fibroblasts, and lower in the heart fibroblasts and brain astrocytes. Furthermore, we observed that NHEJ efficiency declined with age. In the 24-month old animals compared to the 5-month old animals, NHEJ efficiency declined 1.8 to 3.8-fold, depending on the tissue, with the strongest decline observed in the skin fibroblasts. The sequence analysis of 300 independent NHEJ repair events showed that, regardless of age, mice utilize microhomology sequences at a significantly higher frequency than expected by chance. Furthermore, the frequency of microhomology-mediated end joining (MMEJ) events increased in the heart and lung fibroblasts of old mice, suggesting that NHEJ becomes more mutagenic with age. In summary, our study provides a versatile mouse model for the analysis of NHEJ in a wide range of tissues and demonstrates that DNA repair by NHEJ declines with age in mice, which could provide a mechanism for age-related genomic instability and increased cancer incidence with age.

Vaidya, Amita; Mao, Zhiyong; Tian, Xiao; Spencer, Brianna; Seluanov, Andrei; Gorbunova, Vera

2014-01-01

35

Transgenic Mice Overexpressing APP and Transforming Growth Factor-?1 Feature Cognitive and Vascular Hallmarks of Alzheimer's Disease  

PubMed Central

High brain levels of amyloid-? (A?) and transforming growth factor-?1 (TGF-?1) have been implicated in the cognitive and cerebrovascular alterations of Alzheimer’s disease (AD). We sought to investigate the impact of combined increases in A? and TGF-?1 on cerebrovascular, neuronal, and mnemonic function using transgenic mice overproducing these peptides (A/T mice). In particular, we measured cerebrovascular reactivity, evoked cerebral blood flow and glucose uptake during brain activation, cholinergic status, and spatial memory, along with cerebrovascular fibrosis, amyloidosis, and astrogliosis, and their evolution with age. An assessment of perfusion and metabolic responses was considered timely, given ongoing efforts for their validation as AD biomarkers. Relative to wild-type littermates, A/T mice displayed an early progressive decline in cerebrovascular dilatory ability, preserved contractility, and reduction in constitutive nitric oxide synthesis that establishes resting vessel tone. Altered levels of vasodilator-synthesizing enzymes and fibrotic proteins, resistance to antioxidant treatment, and unchanged levels of the antioxidant enzyme, superoxide dismutase-2, accompanied these impairments. A/T mice featured deficient neurovascular and neurometabolic coupling to whisker stimulation, cholinergic denervation, cerebral and cerebrovascular A? deposition, astrocyte activation, and impaired Morris water maze performance, which gained severity with age. The combined A?- and TGF-?1-driven pathology recapitulates salient cerebrovascular, neuronal, and cognitive AD landmarks and yields a versatile model toward highly anticipated diagnostic and therapeutic tools for patients featuring A? and TGF-?1 increments.

Ongali, Brice; Nicolakakis, Nektaria; Lecrux, Clotilde; Aboulkassim, Tahar; Rosa-Neto, Pedro; Papadopoulos, Panayiota; Tong, Xin-Kang; Hamel, Edith

2010-01-01

36

Transgenic mice overexpressing APP and transforming growth factor-beta1 feature cognitive and vascular hallmarks of Alzheimer's disease.  

PubMed

High brain levels of amyloid-? (A?) and transforming growth factor-?1 (TGF-?1) have been implicated in the cognitive and cerebrovascular alterations of Alzheimer's disease (AD). We sought to investigate the impact of combined increases in A? and TGF-?1 on cerebrovascular, neuronal, and mnemonic function using transgenic mice overproducing these peptides (A/T mice). In particular, we measured cerebrovascular reactivity, evoked cerebral blood flow and glucose uptake during brain activation, cholinergic status, and spatial memory, along with cerebrovascular fibrosis, amyloidosis, and astrogliosis, and their evolution with age. An assessment of perfusion and metabolic responses was considered timely, given ongoing efforts for their validation as AD biomarkers. Relative to wild-type littermates, A/T mice displayed an early progressive decline in cerebrovascular dilatory ability, preserved contractility, and reduction in constitutive nitric oxide synthesis that establishes resting vessel tone. Altered levels of vasodilator-synthesizing enzymes and fibrotic proteins, resistance to antioxidant treatment, and unchanged levels of the antioxidant enzyme, superoxide dismutase-2, accompanied these impairments. A/T mice featured deficient neurovascular and neurometabolic coupling to whisker stimulation, cholinergic denervation, cerebral and cerebrovascular A? deposition, astrocyte activation, and impaired Morris water maze performance, which gained severity with age. The combined A?- and TGF-?1-driven pathology recapitulates salient cerebrovascular, neuronal, and cognitive AD landmarks and yields a versatile model toward highly anticipated diagnostic and therapeutic tools for patients featuring A? and TGF-?1 increments. PMID:21088218

Ongali, Brice; Nicolakakis, Nektaria; Lecrux, Clotilde; Aboulkassim, Tahar; Rosa-Neto, Pedro; Papadopoulos, Panayiota; Tong, Xin-Kang; Hamel, Edith

2010-12-01

37

CXC receptor knockout mice: Characterization of skeletal features and membranous bone healing in the adult mouse  

Microsoft Academic Search

The potential role of CXC chemokines bearing the glu-leu-arg (ELR) motif in bone repair was studied using a cranial defect (CD) model in mice lacking the CXC receptor (mCXCR?\\/? knockout mice), which is homologous to knockout of the human CXC receptor 2 (CXCR2) gene. During the inflammatory stage of bone repair, ELR CXC chemokines are released by inflammatory cells and

David S. Bischoff; Taylor Sakamoto; Kenji Ishida; Nalini S. Makhijani; Helen E. Gruber; Dean T. Yamaguchi

2011-01-01

38

Mice Software Design and Physics Performance  

NASA Astrophysics Data System (ADS)

The design philosophy and key features of the Muon Ionisation Cooling Experiment (MICE) software (G4MICE) is presented. The performance of the analysis is demonstrated through a number of Monte Carlo simulations.

Ellis, Malcolm

2008-06-01

39

Transgenic Mice Demonstrate Novel Promoter Regions for Tissue-Specific Expression of the Urokinase Receptor Gene  

PubMed Central

The urokinase-type plasminogen activator receptor (u-PAR) contributes to cell migration and proteolysis in normal and cancerous tissues. Currently, there are no reports on the regulatory regions directing tissue-specific expression. Consequently, we undertook a study to identify novel promoter regions required for expression of this gene in transgenic mice bearing a LacZ reporter regulated by varying amounts (0.4, 1.5, and 8.5 kb) of upstream sequence. The 0.4-kb u-PAR upstream sequence directed weak and strong LacZ expression in the placenta and epididymis, respectively, both of which are tissues that express endogenous u-PAR. Conversely, transgene expression in the apical cells of the colon positive for endogenous u-PAR protein required 1.5 kb of upstream sequence for optimal expression. Furthermore, chromatin accessibility assays coupled with real-time polymerase chain reaction suggested a putative regulatory region spanning ?1295/?1192 driving u-PAR expression in colonic cells. Interestingly, placental transgene expression was augmented with the 8.5-kb upstream fragment compared with the shorter 1.5-kb fragment indicating contributing element(s) between ?1.5 and ?8.5 kb. Thus, while 0.4 kb of upstream sequence directs u-PAR expression in the epididymis, sequences located between ?0.4 and ?1.5 kb and between ?1.5 and ?8.5 kb are required for optimal tissue-specific expression in the colon and the placenta, respectively.

Wang, Heng; Hicks, John; Khanbolooki, Parham; Kim, Sun-Jin; Yan, Chunhong; Wang, Yao; Boyd, Douglas

2003-01-01

40

G protein-coupled receptor kinase-3-deficient mice exhibit WHIM syndrome features and attenuated inflammatory responses.  

PubMed

Chemokine receptor interactions coordinate leukocyte migration in inflammation. Chemokine receptors are GPCRs that when activated, are phosphorylated by GRKs to turn off G protein-mediated signaling yet recruit additional signaling machinery. Recently, GRK3 was identified as a negative regulator of CXCL12/CXCR4 signaling that is defective in human WHIM syndrome. Here, we report that GRK3-/- mice exhibit numerous features of human WHIM, such as impaired CXCL12-mediated desensitization, enhanced CXCR4 signaling to ERK activation, altered granulocyte migration, and a mild myelokathexis. Moreover, GRK3-/- protects mice from two acute models of inflammatory arthritis (K/BxN serum transfer and CAIA). In these granulocyte-dependent disease models, protection of GRK3-/- mice is mediated by retention of cells in the marrow, fewer circulating granulocytes in the peripheral blood, and reduced granulocytes in the joints during active inflammation. In contrast to WHIM, GRK3-/- mice have minimal hypogammaglobulinemia and a peripheral leukocytosis with increased lymphocytes and absent neutropenia. Thus, we conclude that the loss of GRK3-mediated regulation of CXCL12/CXCR4 signaling contributes to some, but not all, of the complete WHIM phenotype and that GRK3 inhibition may be beneficial in the treatment of inflammatory arthritis. PMID:23935208

Tarrant, Teresa K; Billard, Matthew J; Timoshchenko, Roman G; McGinnis, Marcus W; Serafin, D Stephen; Foreman, Oded; Esserman, Denise A; Chao, Nelson J; Lento, William E; Lee, David M; Patel, Dhavalkumar; Siderovski, David P

2013-12-01

41

Targeted disruption of the Hexa gene results in mice with biochemical and pathologic features of Tay-Sachs disease  

SciTech Connect

Tay-Sachs disease, the prototype of the G{sub M2} gangliosidoses, is a catastrophic neurodegenerative disorder of infancy. The disease is caused by mutations in the HEXA gene resulting in an absence of the lysosomal enzyme, {beta}-hexosaminidase A. As consequence of the enzyme deficiency, G{sub M2} ganglioside accumulates progressively, beginning early in fetal life, to excessive amounts in the central nervous system (CNS). Rapid mental and motor deterioration starting in the first year of life leads to death by 2 to 4 years of age. Through the targeted disruption of the Hexa gene in embryonic stem cells, we have produced mice with biochemical and neuropathologic features of Tay-Sachs disease. The mutant mice exhibited less than 1% of normal {beta}-hexosaminidase A activity and accumulated G{sub M2} ganglioside in their CNS in an age-dependent manner. The accumulated ganglioside was stored in neurons as membranous cytoplasmic bodies characteristically found in the neurons of Tay-Sachs disease patients. At three to five months of age the mutant mice showed no apparent defects in motor or memory function. These {beta}-hexosaminidase A deficient mice should be useful for devising strategies to introduce functional enzymes and genes into the CNS. This model may also be valuable for studying the biochemical and pathologic changes occurring during the course of the disease.

Proia, R.L.; Yamanaka, S.; Johnson, M.D. [and others

1994-09-01

42

Targeted disruption of the Hexa gene results in mice with biochemical and pathologic features of Tay-Sachs disease.  

PubMed Central

Tay-Sachs disease, the prototype of the GM2 gangliosidoses, is a catastrophic neurodegenerative disorder of infancy. The disease is caused by mutations in the HEXA gene resulting in an absence of the lysosomal enzyme, beta-hexosaminidase A. As a consequence of the enzyme deficiency, GM2 ganglioside accumulates progressively, beginning early in fetal life, to excessive amounts in the central nervous system. Rapid mental and motor deterioration starting in the first year of life leads to death by 2-4 years of age. Through the targeted disruption of the mouse Hexa gene in embryonic stem cells, we have produced mice with biochemical and neuropathologic features of Tay-Sachs disease. The mutant mice displayed < 1% of normal beta-hexosaminidase A activity and accumulated GM2 ganglioside in their central nervous system in an age-dependent manner. The accumulated ganglioside was stored in neurons as membranous cytoplasmic bodies characteristically found in the neurons of Tay-Sachs disease patients. At 3-5 months of age, the mutant mice showed no apparent defects in motor or memory function. These beta-hexosaminidase A-deficient mice should be useful for devising strategies to introduce functional enzyme and genes into the central nervous system. This model may also be valuable for studying the biochemical and pathologic changes occurring during the course of the disease. Images

Yamanaka, S; Johnson, M D; Grinberg, A; Westphal, H; Crawley, J N; Taniike, M; Suzuki, K; Proia, R L

1994-01-01

43

The mitochondria-targeted antioxidant MitoQ decreases features of the metabolic syndrome in ATM+/-/ApoE-/- mice.  

PubMed

A number of recent studies suggest that mitochondrial oxidative damage may be associated with atherosclerosis and the metabolic syndrome. However, much of the evidence linking mitochondrial oxidative damage and excess reactive oxygen species (ROS) with these pathologies is circumstantial. Consequently the importance of mitochondrial ROS in the etiology of these disorders is unclear. Furthermore, the potential of decreasing mitochondrial ROS as a therapy for these indications is not known. We assessed the impact of decreasing mitochondrial oxidative damage and ROS with the mitochondria-targeted antioxidant MitoQ in models of atherosclerosis and the metabolic syndrome (fat-fed ApoE(-/-) mice and ATM(+/-)/ApoE(-/-) mice, which are also haploinsufficient for the protein kinase, ataxia telangiectasia mutated (ATM). MitoQ administered orally for 14weeks prevented the increased adiposity, hypercholesterolemia, and hypertriglyceridemia associated with the metabolic syndrome. MitoQ also corrected hyperglycemia and hepatic steatosis, induced changes in multiple metabolically relevant lipid species, and decreased DNA oxidative damage (8-oxo-G) in multiple organs. Although MitoQ did not affect overall atherosclerotic plaque area in fat-fed ATM(+/+)/ApoE(-/-) and ATM(+/-)/ApoE(-/-) mice, MitoQ reduced the macrophage content and cell proliferation within plaques and 8-oxo-G. MitoQ also significantly reduced mtDNA oxidative damage in the liver. Our data suggest that MitoQ inhibits the development of multiple features of the metabolic syndrome in these mice by affecting redox signaling pathways that depend on mitochondrial ROS such as hydrogen peroxide. These findings strengthen the growing view that elevated mitochondrial ROS contributes to the etiology of the metabolic syndrome and suggest a potential therapeutic role for mitochondria-targeted antioxidants. PMID:22210379

Mercer, John R; Yu, Emma; Figg, Nichola; Cheng, Kian-Kai; Prime, Tracy A; Griffin, Julian L; Masoodi, Mojgan; Vidal-Puig, Antonio; Murphy, Michael P; Bennett, Martin R

2012-03-01

44

Functional and morphological features of skeletal muscle from mutant mice lacking both type 1 and type 3 ryanodine receptors.  

PubMed Central

1. We generated mice with targeted disruptions in the genes for both ryanodine receptor type 1 (RyR-1) and type 3 (RyR-3) to study the functional roles of RyR subtypes in skeletal muscle. 2. In permeabilized myocytes lacking both the RyRs, the Ca(2+)-induced Ca2+ release (CICR) mechanism was completely lost, and caffeine failed to induce Ca2+ release. 3. Replacement of potassium methanesulphonate in an experimental intracellular solution with choline chloride resulted in Ca2+ release in the wild-type muscle but not in the mutant muscle lacking RyR-1. 4. The double-mutant mice exhibited more severe muscular degeneration than RyR-1-deficient mice with formation of large vacuoles and swollen mitochondria while structural coupling between T-tubules and the sarcoplasmic reticulum was retained. 5. These results demonstrate that CICR is mediated solely by RyR-1 and RyR-3 in skeletal muscle cells, and suggest that RyR-1 is involved in Cl(-)-induced Ca2+ release. The results also suggest the presence of molecular components other than RyRs responsible for the triad formation. RyR-3 may have a role in the normal morphogenesis of skeletal muscle cells, although functionally it can be replaced by RyR-1. Images Figure 4

Ikemoto, T; Komazaki, S; Takeshima, H; Nishi, M; Noda, T; Iino, M; Endo, M

1997-01-01

45

Morphological and electrophysiological features of motor neurons and putative interneurons in the dorsal vagal complex of rats and mice.  

PubMed

The dorsal motor nucleus of the vagus (DMV) contains preganglionic motor neurons that control viscera along the subdiaphragmatic digestive tract, but may also contain neurons that do not project to the viscera. Neurons that expressed EGFP 60-72 h subsequent to PRV-152 inoculation of vagal terminals in the stomach wall were targeted for whole-cell patch-clamp recording and biocytin filling in transverse brainstem slices from rats and their quantitative morphological and electrophysiological characteristics were compared with uninfected cells. Over 90% of PRV-152 labeled neurons were also labeled subsequent to intraperitoneal injection of FluoroGold, indicating that most were preganglionic motor neurons. In reconstructed neurons with an identifiable axon trajectory, two cellular subtypes were distinguished. The axon projected ventrolaterally from the DMV in 44 of 49 cells and these were likely to be vagal motor neurons. Axons of other neurons ramified within the nucleus tractus solitarius (NTS) or DMV. These cells were smaller and otherwise morphologically distinct from putative motor neurons. Transgenic mice with GFP-expressing inhibitory neurons (i.e., GIN mice) were used to identify a GABAergic subset of DMV neurons. These neurons had locally ramifying axons and formed a morphologically distinct subset of DMV cells, which were similar in size and axon trajectory to GABAergic neurons in the NTS. Most neurons in the DMV therefore possess morphological features of motor neurons, but locally projecting cells and inhibitory neurons with distinct morphological features are also found within the DMV. These cells likely contribute to regulation of vagal function. PMID:19619517

Gao, Hong; Glatzer, Nicholas R; Williams, Kevin W; Derbenev, Andrei V; Liu, Dan; Smith, Bret N

2009-09-29

46

Immunoregulation of genetically controlled acquired responses to Leishmania donovani infection in mice: demonstration and characterization of suppressor T cells in noncure mice.  

PubMed Central

On a B10 genetic background, genes in the I region of H-2 influence the development of acquired T-cell mediated immunity to Leishmania donovani infection in mice. In previous studies, noncure in H-2d mice could be abrogated by pretreatments with cyclophosphamide or sublethal irradiation. The prophylactic effect of these pretreatments was consistent with deletion of the precursors of suppressor T cells suppressing T-cell-mediated immune responses. In this study, cell transfer experiments provide direct evidence for the role of suppressor T cells in the noncure response. T-cell-enriched populations isolated from the spleens of B10.D2/n mice infected 30, 61, or 85 days previously reversed the prophylactic effect of sublethal irradiation when injected before infection into B10.D2/n mice that had received 550 rads. B-cell-enriched populations failed to transfer suppression in this manner, and T-cell-enriched populations from the spleens of normal B10.D2/n mice had only a transient effect on liver parasite loads. Transfer of suppression with the T-cell-enriched populations from infected donors was abrogated by pretreatment with anti-Thy-1.2 and anti-Lyt-1.2 antisera plus complement but not by pretreatment with anti-Lyt-2.2 plus complement, indicating that the suppressor T cell involved has an Lyt-1+2- surface phenotype. Results are discussed in relation to the possible mechanism of H-2-linked control.

Blackwell, J M; Ulczak, O M

1984-01-01

47

Design and operating features of the high-level waste vitrification system for the West Valley demonstration project  

SciTech Connect

A liquid-fed joule-heated ceramic melter system is the reference process for immobilization of the high-level liquid waste in the US and several foreign countries. This system has been under development for over ten years at Pacific Northwest Laboratory and other national laboratories operated for the US Department of Energy. Pacific Northwest Laboratory contributed to this research through its Nuclear Waste Treatment Program and used applicable data to design and test melters and related systems using remote handling of simulated radioactive wastes. This report describes the equipment designed in support of the high-level waste vitrification program at West Valley, New York. Pacific Northwest Laboratory worked closely with West Valley Nuclear Services Company to design a liquid-fed ceramic melter, a liquid waste preparation and feed tank and pump, an off-gas treatment scrubber, and an enclosed turntable for positioning the waste canisters. Details of these designs are presented including the rationale for the design features and the alternatives considered.

Siemens, D.H.; Beary, M.M.; Barnes, S.M.; Berger, D.N.; Brouns, R.A.; Chapman, C.C.; Jones, R.M.; Peters, R.D.; Peterson, M.E.

1986-03-01

48

Demonstration of motionless Knudsen pump based micro-gas chromatography featuring micro-fabricated columns and on-column detectors.  

PubMed

This paper reports the investigation of a micro-gas chromatography (?GC) system that utilizes an array of miniaturized motionless Knudsen pumps (KPs) as well as microfabricated separation columns and optical detectors. A prototype system was built to achieve a flow rate of 1 mL min(-1) and 0.26 mL min(-1) for helium and dry air, respectively, when they were used as carrier gas. This system was then employed to evaluate GC performance compromises and demonstrate the ability to separate and detect gas mixtures containing analytes of different volatilities and polarities. Furthermore, the use of pressure programming of the KP array was demonstrated to significantly shorten the analysis time while maintaining a high detection resolution. Using this method, we obtained a high resolution detection of 5 alkanes of different volatilities within 5 min. Finally, we successfully detected gas mixtures of various polarities using a tandem-column ?GC configuration by installing two on-column optical detectors to obtain complementary chromatograms. PMID:21869988

Liu, Jing; Gupta, Naveen K; Wise, Kensall D; Gianchandani, Yogesh B; Fan, Xudong

2011-10-21

49

An Intradermal Inoculation Model of Scrub Typhus in Swiss CD-1 Mice Demonstrates More Rapid Dissemination of Virulent Strains of Orientia tsutsugamushi  

PubMed Central

Scrub typhus is an important endemic disease of the Asia-Pacific region caused by Orientia tsutsugamushi. To develop an effective vaccine to prevent scrub typhus infection, a better understanding of the initial host-pathogen interaction is needed. The objective of this study was to investigate early bacterial dissemination in a CD-1 Swiss outbred mouse model after intradermal injection of O. tsutsugamushi. Three human pathogenic strains of O. tsutsugamushi (Karp, Gilliam, and Woods) were chosen to investigate the early infection characteristics associated with bacterial virulence. Tissue biopsies of the intradermal injection site and draining lymph nodes were examined using histology and immunohistochemistry to characterize bacterial dissemination, and correlated with quantitative real-time PCR for O. tsutsugamushi in blood and tissue from major organs. Soluble adhesion molecules were measured to examine cellular activation in response to infection. No eschar formation was seen at the inoculation site and no clinical disease developed within the 7 day period of observation. However, O. tsutsugamushi was localized at the injection site and in the draining lymph nodes by day 7 post inoculation. Evidence of leukocyte and endothelial activation was present by day 7 with significantly raised levels of sL-selectin, sICAM-1 and sVCAM-1. Infection with the Karp strain was associated with earlier and higher bacterial loads and more extensive dissemination in various tissues than the less pathogenic Gilliam and Woods strains. The bacterial loads of O. tsutsugamushi were highest in the lungs and spleens of mice inoculated with Karp and Gilliam, but not Woods strains. Strains of higher virulence resulted in more rapid systemic infection and dissemination in this model. The CD-1 mouse intradermal inoculation model demonstrates features relevant to early scrub typhus infection in humans, including the development of regional lymphadenopathy, leukocyte activation and distant organ dissemination after low-dose intradermal injection with O. tsutsugamushi.

Sunyakumthorn, Piyanate; Paris, Daniel H.; Chan, Teik-Chye; Jones, Margaret; Luce-Fedrow, Alison; Chattopadhyay, Suchismita; Jiang, Ju; Anantatat, Tippawan; Turner, Gareth D. H.; Day, Nicholas P. J.; Richards, Allen L.

2013-01-01

50

Boron neutron capture therapy demonstrated in mice bearing EMT6 tumors following selective delivery of boron by rationally designed liposomes  

PubMed Central

The application of boron neutron capture therapy (BNCT) following liposomal delivery of a 10B-enriched polyhedral borane and a carborane against mouse mammary adenocarcinoma solid tumors was investigated. Unilamellar liposomes with a mean diameter of 134 nm or less, composed of an equimolar mixture of cholesterol and 1,2-distearoyl-sn-glycero-3-phosphocholine and incorporating Na3[1-(2?-B10H9)-2-NH3B10H8] in the aqueous interior and K[nido-7-CH3(CH2)15-7,8-C2B9H11] in the bilayer, were injected into the tail veins of female BALB/c mice bearing right flank EMT6 tumors. Biodistribution studies indicated that two identical injections given 24 h apart resulted in tumor boron levels exceeding 67 µg/g tumor at 54 h—with tumor/blood boron ratios being greatest at 96 h (5.68:1; 43 µg boron/g tumor)—following the initial injection. For BNCT experiments, tumor-bearing mice were irradiated 54 h after the initial injection for 30 min with thermal neutrons, resulting in a total fluence of 1.6 × 1012 neutrons per cm2 (±7%). Significant suppression of tumor growth was observed in mice given BNCT vs. control mice (only 424% increase in tumor volume at 14 d post irradiation vs. 1551% in untreated controls). In a separate experiment in which mice were given a second injection/irradiation treatment 7 d after the first, the tumor growth was vastly diminished (186% tumor volume increase at 14 d). A similar response was obtained for mice irradiated for 60 min (169% increase at 14 d), suggesting that neutron fluence was the limiting factor controlling BNCT efficacy in this study.

Kueffer, Peter J.; Maitz, Charles A.; Khan, Aslam A.; Schuster, Seth A.; Shlyakhtina, Natalia I.; Jalisatgi, Satish S.; Brockman, John D.; Nigg, David W.; Hawthorne, M. Frederick

2013-01-01

51

Demonstration of 22nm SRAM features with patternable hafnium oxide-based resist material using electron-beam lithography  

NASA Astrophysics Data System (ADS)

To fulfill the requirements of future technology nodes new resists with high resolution, high sensitivity and low LWR and LER respectively are needed. A new inorganic non-chemically amplified resist (XE15IB, an experimental resist provided by Inpria Corp.) was investigated. The resist is spin-cast from aqueous solution and is based on hafnium oxide. Metal oxide based resist as XE15IB supersede other resist materials due to its high etch resistance.1, 2 This new material can be considered as a direct patternable spin on hard mask. XE15IB was processed in a 300mm complementary metal oxide semiconductor (CMOS) manufacturing environment and exposed on a 50 kV VISTEC SB3050DW variable shaped electron beam direct writer at Fraunhofer Center Nanoelectronic Technologies (CNT). The resist was evaluated in terms of contrast, sensitivity and resolution. The process characteristics required for CMOS manufacturing such as delay stability were also examined. Furthermore, by printing a large static random access Memory (SRAM) pattern (design CD of 22 nm), the exposure of a real application pattern was demonstrated.

Thrun, Xaver; Choi, Kang-Hoon; Freitag, Martin; Grenville, Andrew; Gutsch, Manuela; Hohle, Christoph; Stowers, Jason K.; Bartha, Johann W.

2012-03-01

52

Motor Neuron Rescue in Spinal Muscular Atrophy Mice Demonstrates That Sensory-Motor Defects Are a Consequence, Not a Cause, of Motor Neuron Dysfunction  

PubMed Central

The loss of motor neurons (MNs) is a hallmark of the neuromuscular disease spinal muscular atrophy (SMA); however, it is unclear whether this phenotype autonomously originates within the MN. To address this question, we developed an inducible mouse model of severe SMA that has perinatal lethality, decreased motor function, motor unit pathology, and hyperexcitable MNs. Using an Hb9-Cre allele, we increased Smn levels autonomously within MNs and demonstrate that MN rescue significantly improves all phenotypes and pathologies commonly described in SMA mice. MN rescue also corrects hyperexcitability in SMA motor neurons and prevents sensory-motor synaptic stripping. Survival in MN-rescued SMA mice is extended by only 5 d, due in part to failed autonomic innervation of the heart. Collectively, this work demonstrates that the SMA phenotype autonomously originates in MNs and that sensory-motor synapse loss is a consequence, not a cause, of MN dysfunction.

Gogliotti, Rocky G.; Quinlan, Katharina A.; Barlow, Courtenay B.; Heier, Christopher R.; Heckman, C. J.

2012-01-01

53

IL10-deficient mice demonstrate multiple organ failure and increased mortality during Escherichia coli peritonitis despite an accelerated bacterial clearance  

Microsoft Academic Search

To determine the role of endogenous IL-10 in local antibacterial host defense and in the development of a systemic inflammatory response syndrome during abdominal sepsis, IL-10 gene-deficient (IL-102\\/2) and wild-type (IL-101\\/1) mice received an i.p. injection with Escherichia coli. Peritonitis was associated with a bacterial dose-dependent increase in IL-10 concentrations in peritoneal fluid and plasma. The recovery of E. coli

Miguel E. Sewnath; Dariusz P. Olszyna; Rakesh Birjmohun; Kate ten F. J. W; Dirk J. Gouma; Tom van der Poll

2001-01-01

54

A Cardiomyocyte-Specific Wdr1 Knockout Demonstrates Essential Functional Roles for Actin Disassembly during Myocardial Growth and Maintenance in Mice.  

PubMed

Actin dynamics are critical for muscle development and function, and mutations leading to deregulation of actin dynamics cause various forms of heritable muscle diseases. AIP1 is a major cofactor of the actin depolymerizing factor/cofilin in eukaryotes, promoting actin depolymerizing factor/cofilin-mediated actin disassembly. Its function in vertebrate muscle has been unknown. To investigate functional roles of AIP1 in myocardium, we generated conditional knockout (cKO) mice with cardiomyocyte-specific deletion of Wdr1, the mammalian homolog of yeast AIP1. Wdr1 cKO mice began to die at postnatal day 13 (P13), and none survived past P24. At P12, cKO mice exhibited cardiac hypertrophy and impaired contraction of the left ventricle. Electrocardiography revealed reduced heart rate, abnormal P wave, and abnormal T wave at P10 and prolonged QT interval at P12. Actin filament (F-actin) accumulations began at P10 and became prominent at P12 in the myocardium of cKO mice. Within regions of F-actin accumulation in myofibrils, the sarcomeric components ?-actinin and tropomodulin-1 exhibited disrupted patterns, indicating that F-actin accumulations caused by Wdr1 deletion result in disruption of sarcomeric structure. Ectopic cofilin colocalized with F-actin aggregates. In adult mice, Wdr1 deletion resulted in similar but much milder phenotypes of heart hypertrophy, F-actin accumulations within myofibrils, and lethality. Taken together, these results demonstrate that AIP1-regulated actin dynamics play essential roles in heart function in mice. PMID:24840128

Yuan, Baiyin; Wan, Ping; Chu, Dandan; Nie, Junwei; Cao, Yunshan; Luo, Wen; Lu, Shuangshuang; Chen, Jiong; Yang, Zhongzhou

2014-07-01

55

A Model of Salmonella Colitis with Features of Diarrhea in SLC11A1 Wild-Type Mice  

Microsoft Academic Search

BackgroundMice do not get diarrhea when orally infected with S. enterica, but pre-treatment with oral aminoglycosides makes them susceptible to Salmonella colitis. However, genetically susceptible ItyS mice (Nramp1G169D allele) die from systemic infection before they develop diarrhea, so a new model is needed to study the pathogenesis of diarrhea. We pretreated ItyR mice (Nramp1G169) with oral kanamycin prior to infecting

Heungjeong Woo; Sharon Okamoto; Donald Guiney; John S. Gunn; Joshua Fierer; Niyaz Ahmed

2008-01-01

56

Proteomic analysis of mice expressing human ApoE demonstrates no differences in global protein solubility between APOE 3 and APOE 4 young mice.  

PubMed

Apolipoprotein E (ApoE) is a major lipid carrier protein. In humans, ApoE is expressed in three polymorphic isoforms, which are encoded by three different alleles APOE2, APOE3, and APOE4. In the brains of Alzheimer's disease (AD) patients, each one of these three allelic isoforms is found in several "isoelectric" protein isoforms (qPI), i.e. protein isoforms resulting from PTMs altering the net charge (q) of the polypeptide. AD is a complex disease in which multiple causes and several risk factors affect the onset and disease outcome. A major risk factor for AD is ApoE4; therefore, it is important to characterize the different ApoE qPIs. We have implemented a detergent-based method for isolation and quantitation of protein isoforms, and we found differences in the solubility of protein isoforms depending on the type of solvent used. In this manuscript, we describe these methods and applied them to young human-ApoE targeted replacement mice. Our results indicate that there are no significant differences in the hippocampus proteome of these mice as a function of the APOE genotype. PMID:23161654

Londono, Carolina; DeKroon, Robert M; Mocanu, Mihaela; Booe, Jessica; Winnik, Witold M; Swank, Adam; Osorio, Cristina; Hamlett, Eric D; Alzate, Oscar

2012-12-01

57

Mice Exposed to Chronic Intermittent Hypoxia Simulate Clinical Features of Deficiency of both Qi and Yin Syndrome in Traditional Chinese Medicine.  

PubMed

Deficiency of both Qi and Yin Syndrome (DQYS) is one of the common syndromes in traditional Chinese medicine (TCM), mainly characterized by tiredness, emaciation, anorexia, fidget, palpitation and rapid pulse, etc. Currently, there is no available animal model which can reflect the clinical features of this syndrome. In the present paper, we observed the time-course changes of whole behavior, body weight, food intake, locomotive activity and electrocardiogram in mice exposed to chronic intermittent hypoxia for 6 weeks, and measured bleeding time at last according to the clinical features of DQYS and one key pathological factor. The results showed that the mice exposed to intermittent hypoxia for certain time presented lackluster hair, dull looking hair, resistance, attacking, body weight loss, food intake decline, locomotive activity decrease, heart rate quickening and T wave elevating, which were similar to the major clinical features of DQYS. Meanwhile, bleeding time shortening was also found, which was consistent with the clinical fact that DQYS often accompanied with blood stasis. The possible explanation was also outlined according to the available literature. Such findings suggested chronic intermittent hypoxia could induce similar symptoms and signs in mice accorded with the clinical features of DQYS, which provided a suitable animal model for evaluation of drugs for the treatment of this syndrome and further exploration of pathological process or correlation of the syndrome and related diseases. PMID:20047893

Chai, Chengzhi; Kou, Junping; Zhu, Danni; Yan, Yongqing; Yu, Boyang

2010-01-01

58

Subchronic and mild social defeat stress accelerates food intake and body weight gain with polydipsia-like features in mice.  

PubMed

Development and characterization of animal models of depression are essential for fully understanding the pathogenesis of depression in humans. We made and analyzed a mouse model exhibiting social deficit and hyperphagia-like behavior using a subchronic and mild social defeat stress (sCSDS) paradigm. The body weight, food and water intake of mice were monitored during a test period, and their behaviors and serum components were analyzed at two stages: immediately after the sCSDS period and 1 month after the sCSDS. The body weight and food intake of defeated mice were significantly higher than control mice at the sCSDS period, and these differences were sustained until 1 month after the sCSDS, whereas the water intake of defeated mice was significantly higher than control mice for the period of sCSDS only. Behavioral analyses revealed that the defeated mice exhibit significant social aversion to unfamiliar mice in a social interaction test and a trend of anxiety-like behavior in an elevated-plus maze test. Possibly due to polydipsia-like symptoms, defeated mice had significantly lower levels of albumin and blood urea nitrogen than control mice immediately after the sCSDS period but not at 1 month after sCSDS. The present study revealed that our sCSDS mice keep much more water in their body than control mice. This study reports the first step toward an understanding of the mechanisms of stress-induced overhydration, over-eating and resultant weight gain. PMID:24875770

Goto, Tatsuhiko; Kubota, Yoshifumi; Tanaka, Yuki; Iio, Wataru; Moriya, Naoko; Toyoda, Atsushi

2014-08-15

59

Decreased Levels of Proapoptotic Factors and Increased Key Regulators of Mitochondrial Biogenesis Constitute New Potential Beneficial Features of Long-lived Growth Hormone Receptor Gene-Disrupted Mice  

PubMed Central

Decreased somatotrophic signaling is among the most important mechanisms associated with extended longevity. Mice homozygous for the targeted disruption of the growth hormone (GH) receptor gene (GH receptor knockout; GHRKO) are obese and dwarf, are characterized by a reduced weight and body size, undetectable levels of GH receptor, high concentration of serum GH, and greatly reduced plasma levels of insulin and insulin-like growth factor-I, and are remarkably long lived. Recent results suggest new features of GHRKO mice that may positively affect longevity—decreased levels of proapoptotic factors and increased levels of key regulators of mitochondrial biogenesis. The alterations in levels of the proapoptotic factors and key regulators of mitochondrial biogenesis were not further improved by two other potential life-extending interventions—calorie restriction and visceral fat removal. This may attribute the primary role to GH resistance in the regulation of apoptosis and mitochondrial biogenesis in GHRKO mice in terms of increased life span.

2013-01-01

60

Temporal evolution of neurophysiological and behavioral features of synapsin I/II/III triple knock-out mice  

PubMed Central

Summary Deletion of one or more synapsin genes in mice results in a spontaneous epilepsy. In these animals, seizures can be evoked by opening or moving the cage. Aim of the present study was to characterize the evolution of the epileptic phenotype by neurophysiological examination and behavioral observation in synapsin triple knock-out (Syn-TKO) mice. Syn-TKO mice were studied from 20 postnatal days (PND) up to 6 months of age by video-EEG recording and behavioral observation. Background EEG spectral analysis was performed and data were compared to WT animals. Syn-TKO revealed rare spontaneous seizures and increased susceptibility to evoked seizures in mice from 60 to 100 PND. Spontaneous and evoked seizures presented similar duration and morphology. At times, seizures were followed by a post-ictal phase characterized by a 4 Hz rhythmic activity and immobility of the animal. Spectral analysis of background EEG evidenced a slowing of the theta-alpha peak in Syn-TKO mice compared to WT mice within the period from PND 40 to 100. These data indicate that Syn-TKO mice do not exhibit a linear progression of the epileptic phenotype, with the period corresponding to a higher susceptibility to evoked seizures characterized by background EEG slowing. This aspect might be connected to brain dysfunction often associated to epilepsy in the interictal period.

Cambiaghi, Marco; Cursi, Marco; Monzani, Elena; Benfenati, Fabio; Comi, Giancarlo; Minicucci, Fabio; Valtorta, Flavia; Leocani, Letizia

2013-01-01

61

SMC-Specific IGF-1 Overexpression in Apoe?/? Mice Does Not Alter Atherosclerotic Plaque Burden but Increases Features of Plaque Stability  

PubMed Central

Objective Growth factors may play a permissive role in atherosclerosis initiation and progression, in part via their promotion of VSMC accumulation in plaques. However, unstable human plaques often have a relative paucity of VSMC which has been suggested to contribute to plaque rupture and/or erosion and to clinical events. IGF-1 is an endocrine and autocrine/paracrine growth factor that is a mitogen for VSMC, but when infused into Apoe?/? mice paradoxically reduces atherosclerosis burden. Methods & Results To determine the effect of stimulation of VSMC growth on atherosclerotic plaque development and to understand mechanisms of IGF-1’s atheroprotective effect we assessed atherosclerotic plaques in mice overexpressing IGF-1 in SMC under the control of the ?SMA promoter, after backcrossing to the Apoe?/? background (SMP8/Apoe?/?). When compared with Apoe?/? mice these SMP8/Apoe?/? mice developed comparable plaque burden after 12 wks on a Western diet, suggesting that the ability of increased circulating IGF-1 to reduce plaque burden was mediated in large part via non-SMC target cells. However, advanced plaques in SMP8/Apoe?/? mice displayed several features of plaque stability, including increased fibrous cap area, ?SMA positive SMC and collagen content and reduced necrotic cores. Conclusion These findings indicate that stimulation of VSMC IGF-1 signaling does not alter total atherosclerotic plaque burden and may improve atherosclerotic plaque stability.

Shai, Shaw-Yung; Sukhanov, Sergiy; Higashi, Yusuke; Vaughn, Charlotte; Kelly, James; Delafontaine, Patrice

2010-01-01

62

Tested Demonstrations.  

ERIC Educational Resources Information Center

Two demonstrations are described: (1) a sunset effect using a gooseneck lamp and 20 sheets of paper and (2) the preparation and determination of structural features of dimethyl sulfoxide (DMSO) by infrared spectroscopy. (SK)

Gilbert, George L.

1982-01-01

63

Meta-Analysis Identifies Gene-by-Environment Interactions as Demonstrated in a Study of 4,965 Mice  

PubMed Central

Identifying environmentally-specific genetic effects is a key challenge in understanding the structure of complex traits. Model organisms play a crucial role in the identification of such gene-by-environment interactions, as a result of the unique ability to observe genetically similar individuals across multiple distinct environments. Many model organism studies examine the same traits but under varying environmental conditions. For example, knock-out or diet-controlled studies are often used to examine cholesterol in mice. These studies, when examined in aggregate, provide an opportunity to identify genomic loci exhibiting environmentally-dependent effects. However, the straightforward application of traditional methodologies to aggregate separate studies suffers from several problems. First, environmental conditions are often variable and do not fit the standard univariate model for interactions. Additionally, applying a multivariate model results in increased degrees of freedom and low statistical power. In this paper, we jointly analyze multiple studies with varying environmental conditions using a meta-analytic approach based on a random effects model to identify loci involved in gene-by-environment interactions. Our approach is motivated by the observation that methods for discovering gene-by-environment interactions are closely related to random effects models for meta-analysis. We show that interactions can be interpreted as heterogeneity and can be detected without utilizing the traditional uni- or multi-variate approaches for discovery of gene-by-environment interactions. We apply our new method to combine 17 mouse studies containing in aggregate 4,965 distinct animals. We identify 26 significant loci involved in High-density lipoprotein (HDL) cholesterol, many of which are consistent with previous findings. Several of these loci show significant evidence of involvement in gene-by-environment interactions. An additional advantage of our meta-analysis approach is that our combined study has significantly higher power and improved resolution compared to any single study thus explaining the large number of loci discovered in the combined study.

Joo, Jong Wha J.; Shih, Diana; Davis, Richard C.; Lusis, Aldons J.; Eskin, Eleazar

2014-01-01

64

Meta-analysis identifies gene-by-environment interactions as demonstrated in a study of 4,965 mice.  

PubMed

Identifying environmentally-specific genetic effects is a key challenge in understanding the structure of complex traits. Model organisms play a crucial role in the identification of such gene-by-environment interactions, as a result of the unique ability to observe genetically similar individuals across multiple distinct environments. Many model organism studies examine the same traits but under varying environmental conditions. For example, knock-out or diet-controlled studies are often used to examine cholesterol in mice. These studies, when examined in aggregate, provide an opportunity to identify genomic loci exhibiting environmentally-dependent effects. However, the straightforward application of traditional methodologies to aggregate separate studies suffers from several problems. First, environmental conditions are often variable and do not fit the standard univariate model for interactions. Additionally, applying a multivariate model results in increased degrees of freedom and low statistical power. In this paper, we jointly analyze multiple studies with varying environmental conditions using a meta-analytic approach based on a random effects model to identify loci involved in gene-by-environment interactions. Our approach is motivated by the observation that methods for discovering gene-by-environment interactions are closely related to random effects models for meta-analysis. We show that interactions can be interpreted as heterogeneity and can be detected without utilizing the traditional uni- or multi-variate approaches for discovery of gene-by-environment interactions. We apply our new method to combine 17 mouse studies containing in aggregate 4,965 distinct animals. We identify 26 significant loci involved in High-density lipoprotein (HDL) cholesterol, many of which are consistent with previous findings. Several of these loci show significant evidence of involvement in gene-by-environment interactions. An additional advantage of our meta-analysis approach is that our combined study has significantly higher power and improved resolution compared to any single study thus explaining the large number of loci discovered in the combined study. PMID:24415945

Kang, Eun Yong; Han, Buhm; Furlotte, Nicholas; Joo, Jong Wha J; Shih, Diana; Davis, Richard C; Lusis, Aldons J; Eskin, Eleazar

2014-01-01

65

A Model of Salmonella Colitis with Features of Diarrhea in SLC11A1 Wild-Type Mice  

PubMed Central

Background Mice do not get diarrhea when orally infected with S. enterica, but pre-treatment with oral aminoglycosides makes them susceptible to Salmonella colitis. However, genetically susceptible ItyS mice (Nramp1G169D allele) die from systemic infection before they develop diarrhea, so a new model is needed to study the pathogenesis of diarrhea. We pretreated ItyR mice (Nramp1G169) with oral kanamycin prior to infecting them with virulent S. Typhimurium strain 14028s in order to study Salmonella-induced diarrhea. We used both a visual scoring system and the measurement of fecal water content to measure diarrhea. BALB/c.D2Nramp1 congenic started losing weight 5 days post-infection and they began to die from colitis 10–14 days after infection. A SPI-1 (invA) mutant caused cecal, but not colonic inflammation and did not cause diarrhea. A phoP- mutant did not cause manifestations of diarrhea in either normal or NADPH-deficient (gp91phox) mice. However, strain 14028s caused severe colitis and diarrhea in gp91phox-deficient mice on an ItyR background. pmr A and F mutants, which are less virulent in orally infected BALB/c mice, were fully virulent in this model of colitis. Conclusions S. enterica must be able to invade the colonic epithelium and to persist in the colon in order to cause colitis with manifestations of diarrhea. The NADPH oxidase is not required for diarrhea in Salmonella colitis. Furthermore, a Salmonella phoP mutant can be cleared from the colon by non-oxidative host defenses.

Woo, Heungjeong; Okamoto, Sharon; Guiney, Donald; Gunn, John S.; Fierer, Joshua

2008-01-01

66

Fibrotic response as a distinguishing feature of resistance and susceptibility to pulmonary infection with Mycobacterium tuberculosis in mice.  

PubMed

The differential susceptibility of inbred mouse strains DBA/2J (susceptible) and C57BL/6J (resistant) to pulmonary tuberculosis following aerosol infection is under complex genetic control. In this report, transcriptional profiling with RNAs from Mycobacterium tuberculosis-infected lungs was used to investigate the physiological response, cell type, and biochemical pathways underlying differential susceptibility to infection. Statistical analysis of cDNA-based microarrays revealed that 1,097 transcripts showed statistically significant changes in abundance (changes of > or = 1.5-fold) in at least one of four experimental group comparisons (C57BL/6J [day 0] versus DBA/2J [day 0] mice, C57BL/6J [day 90] versus DBA/2J [day 90] mice, C57BL/6J [day 90] versus C57BL/6J [day 0] mice, or DBA/2J [day 90] versus DBA/2J [day 0] mice). A group of genes showing very high degrees of significance (changes of > or = 2.0-fold) displayed enrichment for transcripts associated with tissue remodeling and the fibrotic response. The differential expression of fibrotic response genes (Sparc, Col1a1, Col1a2, Col4a1, and Col4a2) in the infected lungs of the two mouse strains was validated by another microarray platform (Affymetrix oligonucleotide chips) and by reverse transcription-PCR. Furthermore, the differential expression of additional genes known to be associated with fibrosis (Mmp2, Timp1, and Arg1) was also validated by these approaches. Overall, these results identify the differential fibrotic response as a pathological basis for the high susceptibility of DBA/2J mice to pulmonary tuberculosis. PMID:17938213

Marquis, Jean-François; Nantel, André; LaCourse, Ronald; Ryan, Lynn; North, Robert J; Gros, Philippe

2008-01-01

67

Smallpox vaccine with integrated IL-15 demonstrates enhanced in vivo viral clearance in immunodeficient mice and confers long term protection against a lethal monkeypox challenge in cynomolgus monkeys  

PubMed Central

Despite the eradication of smallpox, there is heightened concern that it could be reintroduced as a result of intentional release of Variola major virus through an act of bioterrorism. The live vaccine that was pivotal in the eradication of smallpox though considered a gold standard for its efficacy still retains sufficient residual virulence that can cause life-threatening sequelae especially in immune deficient individuals. Therefore, a safer smallpox vaccine that can match the efficacy of first generation vaccines is urgently needed. We previously reported that the integration of human IL-15 cytokine into the genome of Wyeth strain of vaccinia (Wyeth/IL-15), the same strain as the licensed vaccine, generates a vaccine with superior immunogenicity and efficacy in a mouse model. We now demonstrate that Wyeth/IL-15 is non-lethal to athymic nude mice when administered intravenously at a dose of 107 plaque forming units and it undergoes enhanced in vivo clearance in these immune deficient mice. Furthermore, a majority of cynomolgus monkeys vaccinated with vaccinia viruses with integrated IL-15, when challenged 3 years later with a lethal dose of monkeypox virus displayed milder clinical manifestations with complete recovery supporting the utility of Wyeth/IL-15 for contemporary populations as a safer and efficacious smallpox vaccine.

Zielinski, Rafal J.; Smedley, Jeremy V.; Perera, Pin-Yu; Silvera, Peter M.; Waldmann, Thomas A.; Capala, Jacek; Perera, Liyanage P.

2010-01-01

68

Induction of oxazolone-mediated features of atopic dermatitis in NOD-scid IL2R?null mice engrafted with human peripheral blood mononuclear cells  

PubMed Central

SUMMARY Animal models mimicking human diseases have been used extensively to study the pathogenesis of autoimmune diseases and the efficacy of potential therapeutics. They are, however, limited with regard to their similarity to the human disease and cannot be used if the antagonist and its cognate receptor require high similarity in structure or binding. Here, we examine the induction of oxazolone-mediated features of atopic dermatitis (AD) in NOD-scid IL2R?null mice engrafted with human peripheral blood mononuclear cells (PBMC). The mice developed the same symptoms as immunocompetent BALB/c mice. Histological alterations induced by oxazolone were characterized by keratosis, epithelial hyperplasia and influx of inflammatory cells into the dermis and epidermis. The cellular infiltrate was identified as human leukocytes, with T cells being the major constituent. In addition, oxazolone increased human serum IgE levels. The response, however, required the engraftment of PBMC derived from patients suffering from AD, which suggests that this model reflects the immunological status of the donor. Taken together, the model described here has the potential to evaluate the efficacy of therapeutics targeting human lymphocytes in vivo and, in addition, might be developed further to elucidate molecular mechanisms inducing and sustaining flares of the disease.

Nolte, Thomas; Zadeh-Khorasani, Maryam; Safarov, Orkhan; Rueff, Franziska; Varga, Rita; Herbach, Nadja; Wanke, Rudiger; Wollenberg, Andreas; Mueller, Thomas; Gropp, Roswitha; Wolf, Eckhard; Siebeck, Matthias

2013-01-01

69

Biological features of core networks that result from a high-fat diet in hepatic and pulmonary tissues in mammary tumour-bearing, obesity-resistant mice.  

PubMed

We previously demonstrated that the chronic consumption of a high-fat diet (HFD) promotes lung and liver metastases of 4T1 mammary carcinoma cells in obesity-resistant BALB/c mice. To examine early transcriptional responses to tumour progression in the liver and lungs of HFD-fed mice, 4-week-old female BALB/c mice were divided into four groups: sham-injected, control diet (CD)-fed; sham-injected, HFD-fed (SH); 4T1 cell-injected, CD-fed (TC); 4T1 cell-injected, HFD-fed (TH). Following 16 weeks of either a CD or HFD, 4T1 cells were injected into the mammary fat pads of mice in the TC and TH groups and all mice were continuously fed identical diets. At 14 d post-injection, RNA was isolated from hepatic and pulmonary tissues for microarray analysis of mRNA expression. Functional annotation and core network analyses were conducted for the TH/SH Unique gene set. Inflammation in hepatic tissues and cell mitosis in pulmonary tissues were the most significant biological functions in the TH/SH Unique gene set. The biological core networks of the hepatic TH/SH Unique gene set were characterised as those genes involved in the activation of acute inflammatory responses (Orm1, Lbp, Hp and Cfb), disordered lipid metabolism and deregulated cell cycle progression. Networks of the pulmonary Unique gene set displayed the deregulation of cell cycle progression (Cdc20, Cdk1 and Bub1b). These HFD-influenced alterations may have led to favourable conditions for the formation of both pro-inflammatory and pro-mitotic microenvironments in the target organs that promote immune cell infiltration and differentiation, as well as the infiltration and proliferation of metastatic tumour cells. PMID:23234678

Kim, Eun Ji; Oh, Hea Young; Heo, Hyoung-Sam; Hong, Ji Eun; Jung, Sung-Jae; Lee, Ki Won; Park, Jong Hoon; Hur, Cheol-Goo; Park, Jung Han Yoon

2013-07-28

70

Physiological Features of the S- and M-cone Photoreceptors of Wild-type Mice from Single-cell Recordings  

PubMed Central

Cone cells constitute only 3% of the photoreceptors of the wild-type (WT) mouse. While mouse rods have been thoroughly investigated with suction pipette recordings of their outer segment membrane currents, to date no recordings from WT cones have been published, likely because of the rarity of cones and the fragility of their outer segments. Recently, we characterized the photoreceptors of Nrl?/? mice, using suction pipette recordings from their “inner segments” (perinuclear region), and found them to be cones. Here we report the use of this same method to record for the first time the responses of single cones of WT mice, and of mice lacking the ?-subunit of the G-protein transducin (Gt??/?), a loss that renders them functionally rodless. Most cones were found to functionally co-express both S- (?max = 360 nm) and M- (?max = 508 nm) cone opsins and to be maximally sensitive at 360 nm (“S-cones”); nonetheless, all cones from the dorsal retina were found to be maximally sensitive at 508 nm (“M-cones”). The dim-flash response kinetics and absolute sensitivity of S- and M-cones were very similar and not dependent on which of the coexpressed cone opsins drove transduction; the time to peak of the dim-flash response was ?70 ms, and ?0.2% of the circulating current was suppressed per photoisomerization. Amplification in WT cones (A ?4 s?2) was found to be about twofold lower than in rods (A ?8 s?2). Mouse M-cones maintained their circulating current at very nearly the dark adapted level even when >90% of their M-opsin was bleached. S-cones were less tolerant to bleached S-opsin than M-cones to bleached M-opsin, but still far more tolerant than mouse rods to bleached rhodopsin, which exhibit persistent suppression of nearly 50% of their circulating current following a 20% bleach. Thus, the three types of mouse opsin appear distinctive in the degree to which their bleached, unregenerated opsins generate “dark light.”

Nikonov, Sergei S.; Kholodenko, Roman; Lem, Janis; Pugh, Edward N.

2006-01-01

71

Lipidomic profiling of phosphocholine-containing brain lipids in mice with sensorimotor deficits and anxiety-like features after exposure to Gulf War agents.  

PubMed

The central nervous system (CNS)-based symptoms of Gulf War Illness (GWI) include motor dysfunction, anxiety, and cognitive impairment. Gulf War (GW) agents, such as pyridostigmine bromide (PB), permethrin (PER), N,N-diethyl-meta-toluamide (DEET), and stress, are among the contributory factors to the pathobiology of GWI. This study characterizes disturbances in phosphocholine-containing lipids that accompany neurobehavioral and neuropathological features associated with GW agent exposure. Exposed mice received PB orally, dermal application of PER and DEET and restraint stress daily for 28 days, while controls received vehicle during this period. Neurobehavioral studies included the rotarod, open field, and Morris water maze tests. Histopathological assessments included glial fibrillary acid protein, CD45, and Nissl staining. Liquid chromatography/mass spectrometry with source collision-induced dissociation in negative and positive ionization scanning modes was performed to characterize brain phosphatidylcholine (PC) and sphingomyelin (SM). A significant increase in ether containing PC (ePC34:0, ePC36:2, and ePC36:1) or long-chain fatty acid-containing PC (38:1, 40:4, 40:2) was observed in exposed mice compared with controls. Among differentially expressed PCs, levels of those with monounsaturated fatty acids were more affected than those with saturated and polyunsaturated fatty acids. Sensorimotor deficits and anxiety, together with an increase in astrocytosis, were observed in exposed mice compared with controls. These lipid changes suggest that alterations in peroxisomal pathways and stearoyl-CoA desaturase activity accompany neurobehavioral and neuropathological changes after GW agent exposure and represent possible treatment targets for the CNS symptoms of GWI. PMID:22798222

Abdullah, Laila; Evans, James E; Bishop, Alex; Reed, Jon M; Crynen, Gogce; Phillips, John; Pelot, Robert; Mullan, Myles A; Ferro, Austin; Mullan, Christopher M; Mullan, Michael J; Ait-Ghezala, Ghania; Crawford, Fiona C

2012-12-01

72

Ultrastructural features of skeletal muscle in adult and aging Ts65Dn mice, a murine model of Down syndrome.  

PubMed

Patients with Down syndrome (DS) suffer from muscle hypotonia and an altered motor coordination whose basic mechanisms are still largely unknown. Interestingly, they show muscle weakness like healthy aged subjects, suggesting possible similarity with sarcopenia: to test this hypothesis, the Ts65Dn mouse, a suitable animal model of DS, was employed. The fine structure of skeletal fibres of the quadriceps femoris muscle was analysed in adult (12 months) and aging (19 months) animals and their age-matched euploid controls by combining morphometry and immunocytochemistry at transmission electron microscopy. Results demonstrated structural alterations of mitochondria and myonuclei reminiscent of those observed in age-related sarcopenia, supporting the hypothesis that trisomy leads to an early aging of skeletal muscle consistent with the multi-systemic premature aging typical of DS. PMID:24596692

Cisterna, Barbara; Costanzo, Manuela; Scherini, Elda; Zancanaro, Carlo; Malatesta, Manuela

2013-10-01

73

Multi-wavelength, 4.32 Gbps UWB radio-over-fiber demonstration featuring a reflective electro-absorption transceiver and low-Cost DWDM grid VCSELs  

Microsoft Academic Search

We demonstrate multi-wavelength UWB radio-over-fiber transmission with 4.32 Gbps throughput over 26.2 km of fiber using a reflective electro-absorption transceiver. Overall EVMs better than -16.8 dB were measured for three VCSEL wavelengths from 1536.3 nm to 1537.8 nm.

Manoj P. Thakur; Terence Quinlan; S. B. Ahmad Anas; D. K. Hunter; S. D. Walker; D. W. Smith; A. Borghesani; D. Moodie

2009-01-01

74

Distinctive radiological features of small hand joints in rheumatoid arthritis and seronegative spondyloarthritis demonstrated by contrast-enhanced (Gd-DTPA) magnetic resonance imaging  

Microsoft Academic Search

A series of patients with clinically early inflammatory joint disease due to rheumatoid arthritis, psoriatic arthritis and Reiter's syndrome were examined by plain film radiography and magnetic resonance imaging (MRI). The spin echo T1-weighted precontrast, T2-weighted, and, especially, T1-weighted postcontrast images demonstrated distinct differences in the distribution of inflamatory changes, both within and adjacent to involved small hand joints. Two

Vladimir Jevtic; Iain Watt; Blaz Rozman; Mojca Kos-Golja; Franci Demsar; Orest Jarh

1995-01-01

75

Postnatal Lethality of P-Cadherin\\/Desmoglein 3 Double Knockout Mice: Demonstration of a Cooperative Effect of these Cell Adhesion Molecules in Tissue Homeostasis of Stratified Squamous Epithelia  

Microsoft Academic Search

To investigate the cooperativity of different cell adhesion molecules in maintaining the structural integrity of the epidermis, we have generated mice deficient for both a classical cadherin, P-cadherin, and a desmosomal cadherin, desmoglein 3. In epithelial cells, P-cadherin is localized to the adherens junction, whereas desmoglein 3 is found in desmosomes. Previous studies have shown that these two junctional complexes

Jennifer M. Lenox; Peter J. Koch; Melanie Lieberman; John R. Stanley; Glenn L. Radice

2000-01-01

76

One Percent Tenofovir Applied Topically to Humanized BLT Mice and Used According to the CAPRISA 004 Experimental Design Demonstrates Partial Protection from Vaginal HIV Infection, Validating the BLT Model for Evaluation of New Microbicide Candidates?  

PubMed Central

Recent iPrEx clinical trial results provided evidence that systemic preexposure prophylaxis (PrEP) with emtricitabine (FTC) and tenofovir disoproxil fumarate (TDF) can partially prevent rectal HIV transmission in humans. Similarly, we have previously demonstrated that systemic administration of the same FTC-TDF combination efficiently prevented rectal transmission in humanized bone marrow/liver/thymus (BLT) mice. The CAPRISA 004 trial recently demonstrated that topical application of the tenofovir could partially prevent vaginal HIV-1 transmission in humans. To further validate the usefulness of the BLT mouse model for testing HIV prevention strategies, we evaluated the topical administration of tenofovir as used in CAPRISA 004 to prevent vaginal HIV transmission in BLT mice. Our results demonstrate that vaginally administered 1% tenofovir significantly reduced HIV transmission in BLT mice (P = 0.002). Together with the results obtained after systemic antiretroviral PrEP, these topical inhibitor data serve to validate the use of humanized BLT mice to evaluate both systemic and topical inhibitors of HIV transmission. Based on these observations, we tested six additional microbicide candidates for their ability to prevent vaginal HIV transmission: a C-peptide fusion inhibitor (C52L), a membrane-disrupting amphipathic peptide inhibitor (C5A), a trimeric d-peptide fusion inhibitor (PIE12-Trimer), a combination of reverse transcriptase inhibitors (FTC-TDF), a thioester zinc finger inhibitor (TC247), and a small-molecule Rac inhibitor (NSC23766). No protection was seen with the Rac inhibitor NSC23766. The thioester compound TC247 offered partial protection. Significant protection was afforded by FTC-TDF, and complete protection was offered by three different peptide inhibitors tested. Our results demonstrate that these effective topical inhibitors have excellent potential to prevent vaginal HIV transmission in humans.

Denton, Paul W.; Othieno, Florence; Martinez-Torres, Francisco; Zou, Wei; Krisko, John F.; Fleming, Elisa; Zein, Sima; Powell, Daniel A.; Wahl, Angela; Kwak, Youn Tae; Welch, Brett D.; Kay, Michael S.; Payne, Deborah A.; Gallay, Philippe; Appella, Ettore; Estes, Jacob D.; Lu, Min; Garcia, J. Victor

2011-01-01

77

One percent tenofovir applied topically to humanized BLT mice and used according to the CAPRISA 004 experimental design demonstrates partial protection from vaginal HIV infection, validating the BLT model for evaluation of new microbicide candidates.  

PubMed

Recent iPrEx clinical trial results provided evidence that systemic preexposure prophylaxis (PrEP) with emtricitabine (FTC) and tenofovir disoproxil fumarate (TDF) can partially prevent rectal HIV transmission in humans. Similarly, we have previously demonstrated that systemic administration of the same FTC-TDF combination efficiently prevented rectal transmission in humanized bone marrow/liver/thymus (BLT) mice. The CAPRISA 004 trial recently demonstrated that topical application of the tenofovir could partially prevent vaginal HIV-1 transmission in humans. To further validate the usefulness of the BLT mouse model for testing HIV prevention strategies, we evaluated the topical administration of tenofovir as used in CAPRISA 004 to prevent vaginal HIV transmission in BLT mice. Our results demonstrate that vaginally administered 1% tenofovir significantly reduced HIV transmission in BLT mice (P = 0.002). Together with the results obtained after systemic antiretroviral PrEP, these topical inhibitor data serve to validate the use of humanized BLT mice to evaluate both systemic and topical inhibitors of HIV transmission. Based on these observations, we tested six additional microbicide candidates for their ability to prevent vaginal HIV transmission: a C-peptide fusion inhibitor (C52L), a membrane-disrupting amphipathic peptide inhibitor (C5A), a trimeric d-peptide fusion inhibitor (PIE12-Trimer), a combination of reverse transcriptase inhibitors (FTC-TDF), a thioester zinc finger inhibitor (TC247), and a small-molecule Rac inhibitor (NSC23766). No protection was seen with the Rac inhibitor NSC23766. The thioester compound TC247 offered partial protection. Significant protection was afforded by FTC-TDF, and complete protection was offered by three different peptide inhibitors tested. Our results demonstrate that these effective topical inhibitors have excellent potential to prevent vaginal HIV transmission in humans. PMID:21593172

Denton, Paul W; Othieno, Florence; Martinez-Torres, Francisco; Zou, Wei; Krisko, John F; Fleming, Elisa; Zein, Sima; Powell, Daniel A; Wahl, Angela; Kwak, Youn Tae; Welch, Brett D; Kay, Michael S; Payne, Deborah A; Gallay, Philippe; Appella, Ettore; Estes, Jacob D; Lu, Min; Garcia, J Victor

2011-08-01

78

Use of matrix metalloproteinase (MMP)-9 knockout mice demonstrates that MMP-9 activity is not absolutely required for G-CSF or Flt-3 ligand-induced hematopoietic progenitor cell mobilization or engraftment.  

PubMed

Recombinant growth factors (GFs) are used to mobilize hematopoietic stem cells (HSCs) for autologous and allogeneic transplantation; however, little is known about the mechanism(s) critical to this process. Increased levels of serum matrix metalloproteinase (MMP)-9 are detected during mobilization by G-CSF in humans or interleukin (IL)-8 in primates and mice, suggesting a role for this molecule in mobilization. Further, antibodies to MMP-9 block IL-8-induced mobilization. To investigate the role of MMP-9, we compared G-CSF and Flt-3 ligand (Flt-3L)-induced mobilization in wild-type (WT) and MMP-9 knockout (KO) mice. The absence of MMP-9 in the KO mice was confirmed by zymography, which also revealed that serum MMP-9 levels were elevated in WT mice following G-CSF administration. We report that MMP-9 KO mice did not have impaired G-CSF- or Flt-3L-induced hematopoietic progenitor mobilization, suggesting that MMP-9 is not an absolute requirement for this process. In addition, MMPs produced by HSCs have been demonstrated to be important for their transmigration; however, we demonstrate that the engraftment of MMP-9-deficient bone marrow HSCs was not impaired in sublethally irradiated WT recipients. We conclude that while MMP-9 may play an important role in GF-induced hematopoietic progenitor mobilization and engraftment in WT animals, compensatory upregulation of enzymes with a similar activity profile to MMP-9 may obscure the impact of MMP-9 deficiency in the KO model. PMID:12832695

Robinson, Simon N; Pisarev, Vladimir M; Chavez, Jennifer M; Singh, Rakesh K; Talmadge, James E

2003-01-01

79

A novel B-domain O-glycoPEGylated FVIII (N8-GP) demonstrates full efficacy and prolonged effect in hemophilic mice models  

PubMed Central

Frequent infusions of intravenous factor VIII (FVIII) are required to prevent bleeding associated with hemophilia A. To reduce the treatment burden, recombinant FVIII with a longer half-life was developed without changing the protein structure. FVIII–polyethylene glycol (PEG) conjugates were prepared using an enzymatic process coupling PEG (ranging from 10 to 80 kDa) selectively to a unique O-linked glycan in the FVIII B-domain. Binding to von Willebrand factor (VWF) was maintained for all conjugates. Upon cleavage by thrombin, the B-domain and the associated PEG were released, generating activated FVIII (FVIIIa) with the same primary structure and specific activity as native FVIIIa. In both FVIII- and VWF-deficient mice, the half-life was found to increase with the size of PEG. In vivo potency and efficacy of FVIII conjugated with a 40-kDa PEG (N8-GP) and unmodified FVIII were not different. N8-GP had a longer duration of effect in FVIII-deficient mouse models, approximately a twofold prolonged half-life in mice, rabbits, and cynomolgus monkeys; however, the prolongation was less pronounced in rats. Binding capacity of N8-GP on human monocyte-derived dendritic cells was reduced compared with unmodified FVIII, resulting in several-fold reduced cellular uptake. In conclusion, N8-GP has the potential to offer efficacious prevention and treatment of bleeds in hemophilia A at reduced dosing frequency.

Kjalke, Marianne; Karpf, Ditte M.; Balling, Kristoffer W.; Johansen, Peter B.; Elm, Torben; ?vlisen, Kristine; Moller, Flemming; Holmberg, Heidi L.; Gudme, Charlotte N.; Persson, Egon; Hilden, Ida; Pelzer, Hermann; Rahbek-Nielsen, Henrik; Jespersgaard, Christina; Bogsnes, Are; Pedersen, Anette A.; Kristensen, Anne K.; Peschke, Bernd; Kappers, Wendy; Rode, Frederik; Thim, Lars; Tranholm, Mikael; Ezban, Mirella; Olsen, Eva H. N.; Bj?rn, S?ren E.

2013-01-01

80

Humanized Mice Recapitulate Key Features of HIV-1 Infection: A Novel Concept Using Long-Acting Anti-Retroviral Drugs for Treating HIV-1  

PubMed Central

Background Humanized mice generate a lymphoid system of human origin subsequent to transplantation of human CD34+ cells and thus are highly susceptible to HIV infection. Here we examined the efficacy of antiretroviral treatment (ART) when added to food pellets, and of long-acting (LA) antiretroviral compounds, either as monotherapy or in combination. These studies shall be inspiring for establishing a gold standard of ART, which is easy to administer and well supported by the mice, and for subsequent studies such as latency. Furthermore, they should disclose whether viral breakthrough and emergence of resistance occurs similar as in HIV-infected patients when ART is insufficient. Methods/Principal Findings NOD/shi-scid/?cnull (NOG) mice were used in all experimentations. We first performed pharmacokinetic studies of the drugs used, either added to food pellets (AZT, TDF, 3TC, RTV) or in a LA formulation that permitted once weekly subcutaneous administration (TMC278: non-nucleoside reverse transcriptase inhibitor, TMC181: protease inhibitor). A combination of 3TC, TDF and TMC278-LA or 3TC, TDF, TMC278-LA and TMC181-LA suppressed the viral load to undetectable levels in 15/19 (79%) and 14/14 (100%) mice, respectively. In successfully treated mice, subsequent monotherapy with TMC278-LA resulted in viral breakthrough; in contrast, the two LA compounds together prevented viral breakthrough. Resistance mutations matched the mutations most commonly observed in HIV patients failing therapy. Importantly, viral rebound after interruption of ART, presence of HIV DNA in successfully treated mice and in vitro reactivation of early HIV transcripts point to an existing latent HIV reservoir. Conclusions/Significance This report is a unique description of multiple aspects of HIV infection in humanized mice that comprised efficacy testing of various treatment regimens, including LA compounds, resistance mutation analysis as well as viral rebound after treatment interruption. Humanized mice will be highly valuable for exploring the antiviral potency of new compounds or compounds targeting the latent HIV reservoir.

Nischang, Marc; Sutmuller, Roger; Gers-Huber, Gustavo; Audige, Annette; Li, Duo; Rochat, Mary-Aude; Baenziger, Stefan; Hofer, Ursula; Schlaepfer, Erika; Regenass, Stephan; Amssoms, Katie; Stoops, Bart; Van Cauwenberge, Anja; Boden, Daniel; Kraus, Guenter; Speck, Roberto F.

2012-01-01

81

Tested Demonstrations.  

ERIC Educational Resources Information Center

Presents the following chemistry lecture demonstrations and experiments: (1) a versatile kinetic demonstration; (2) the Bakelite Demonstration; (3) applying Beer's law; and (4) entropy calculations. (HM)

Gilbert, George L., Ed.

1978-01-01

82

Tested Demonstrations.  

ERIC Educational Resources Information Center

Three demonstrations (a mechanical model of chemical equilibrium, a demonstration of Raoult's Law, and a demonstration of permanganate reduction) are presented. Materials and procedures are detailed. (CW)

Gilbert, George L., Ed.

1990-01-01

83

Follicular Thyroid Cancers Demonstrate Dual Activation of PKA and mTOR as Modeled by Thyroid-Specific Deletion of Prkar1a and Pten in Mice.  

PubMed

Context: Thyroid cancer is the most common form of endocrine cancer, and it is a disease whose incidence is rapidly rising. Well-differentiated epithelial thyroid cancer can be divided into papillary thyroid cancer (PTC) and follicular thyroid cancer (FTC). Although FTC is less common, patients with this condition have more frequent metastasis and a poorer prognosis than those with PTC. Objective: The objective of this study was to characterize the molecular mechanisms contributing to the development and metastasis of FTC. Design: We developed and characterized mice carrying thyroid-specific double knockout of the Prkar1a and Pten tumor suppressor genes and compared signaling alterations observed in the mouse FTC to the corresponding human tumors. Setting: The study was conducted at an academic research laboratory. Human samples were obtained from academic hospitals. Patients: Deidentified, formalin-fixed, paraffin-embedded (FFPE) samples were analyzed from 10 control thyroids, 30 PTC cases, five follicular variant PTC cases, and 10 FTC cases. Interventions: There were no interventions. Main outcome measures: Mouse and patient samples were analyzed for expression of activated cAMP response element binding protein, AKT, ERK, and mammalian target of rapamycin (mTOR). Murine FTCs were analyzed for differential gene expression to identify genes associated with metastatic progression. Results: Double Prkar1a-Pten thyroid knockout mice develop FTC and recapitulate the histology and metastatic phenotype of the human disease. Analysis of signaling pathways in FTC showed that both human and mouse tumors exhibited strong activation of protein kinase A and mTOR. The development of metastatic disease was associated with the overexpression of genes required for cell movement Conclusions: These data imply that the protein kinase A and mTOR signaling cascades are important for the development of follicular thyroid carcinogenesis and may suggest new targets for therapeutic intervention. Mouse models paralleling the development of the stages of human FTC should provide important new tools for understanding the mechanisms of FTC development and progression and for evaluating new therapeutics. PMID:24512487

Pringle, Daphne R; Vasko, Vasily V; Yu, Lianbo; Manchanda, Parmeet K; Lee, Audrey A; Zhang, Xiaoli; Kirschner, Jessica M; Parlow, Albert F; Saji, Motoyasu; Jarjoura, David; Ringel, Matthew D; La Perle, Krista M D; Kirschner, Lawrence S

2014-05-01

84

Tested Demonstrations.  

ERIC Educational Resources Information Center

Describes two chemistry demonstrations including a demonstration of chemical inhibition and "The Rayleigh Fountain" which demonstrates the polarity of the water molecule. Provides instructions and explanations for each demonstration. (CW)

Gilbert, George L., Ed.

1988-01-01

85

Tested Demonstrations.  

ERIC Educational Resources Information Center

Details three demonstrations for use in chemistry classrooms. Includes: "A Demonstration of Corrosion by Differential Aeration"; "A Simple Demonstration of the Activation Energy Concept"; and "A Boiling Demonstration at Room Temperature." Each description includes equipment, materials, and methods. (CW)

Gilbert, George L., Ed.

1988-01-01

86

[Features of behavioral reactions of chronically irradiated mice in the raised crosswise labyrinth with various genetically determined radiosensitivity and possibilities of their modification by the fungal biopolymer complex].  

PubMed

Structural elements of the central nervous system--neurons, along with the higher neuroendocrine structures and the hypothalamus centres, show high sensitivity to a chronic action of low doses of ionizing radiation (IR) in view of their extreme enrichment by phospholipids and intensive supply by oxygen, creating favorable conditions for the development of oxidizing stress. Stressful influences cause negative emotions in the behaviour of animals manifested as fear or uneasiness. The study represents the results of comparative research into the behavioral reactions characterized by uneasiness in the Balb/c and C57bl/6 mice exposed to a chronic irradiation at low doses. The chitin-melanin-glucan complex from fungi Fomes fomentarius (ChMG) was approved as an adaptive agent. It has been shown that under identical conditions, deposition levels of radionuclides 137Cs and 90Sr are raised in mice with IR hypersensitivity--line Balb/c, in comparison with less radio sensitive mice--line C57bl/6. Simultaneously, Balb/c mice were observed to exhibit the signs of a more anxious behaviour in the new environment. Chronic external and internal radiation exposure to rare ionizing radiation at low doses promotes strengthening of anxiety and phobic reactions in mice with IR hypersensitivity. The use of ChMG in animals neutralized the increase in anxiety and phobic reactions after a prolonged irradiation, thus indicating the presence in ChMG of the anxiolitic activity along with the above mentioned powerful radiosorbent, antioxidant, gene protective and immunomodulatory properties. PMID:23786031

Seniuk, O F; Gorovo?, L F; Kovalev, V A; Palamar, L A; Krul', N I; Zhidkov, A V; Chemerski?, G F; Kireev, S I; Khatuntseva, I V

2013-01-01

87

Tested Demonstrations.  

ERIC Educational Resources Information Center

Describes three flame test demonstrations including "Student-Presented Demonstrations on the Colors of Transition Metal Complexes,""A Flame Test Demonstration Device," and "Vivid Flame Tests." Preparation and procedures are discussed. Included in the first demonstration is an evaluation scheme for grading student demonstrations. (CW)

Gilbert, George L., Ed.

1988-01-01

88

Demonstration of Hepatitis C Virus RNA with In Situ Hybridization Employing a Locked Nucleic Acid Probe in Humanized Liver of Infected Chimeric Mice and in Needle-Biopsied Human Liver  

PubMed Central

Background. In situ hybridization (ISH) with high sensitivity has been requested to demonstrate hepatitis C virus (HCV) RNA in formalin-fixed, paraffin-embedded (FFPE) sections of the liver. Methods. ISH employing a locked-nucleic-acid- (LNA-)modified oligonucleotide probe and biotin-free catalyzed signal amplification system (CSAII) was applied to HCV-RNA detection in the liver tissue. Nested reverse-transcription polymerase chain reaction (RT-PCR) was performed for HCV genotyping using total RNA extracted from FFPE sections. The target tissues included FFPE tissue sections of humanized livers in HCV-infected chimeric mice (HCV genotypes 1a, 1b, and 2a and noninfected) and of needle-biopsied livers from HCV-infected patients. Results. HCV-RNA was demonstrated with the ISH technique in HCV-infected liver tissues from both chimeric mice and 9 (82%) of 11 patients with HCV infection. The HCV signals were sensitive to RNase. Nested RT-PCR confirmed the genotype in 8 (73%) of 11 livers (type 1b: 6 lesions and type 2a: 2 lesions). HCV-RNA was not identified in chronic hepatitis B lesions, fatty liver, autoimmune hepatitis, and hepatocellular carcinoma. Conclusion. ISH using the LNA-modified oligonucleotide probe and CSAII was applicable to detecting HCV-RNA in routinely prepared FFPE liver specimens.

Shiogama, Kazuya; Inada, Ken-ichi; Kohara, Michinori; Teramoto, Hidemi; Mizutani, Yasuyoshi; Onouchi, Takanori; Tsutsumi, Yutaka

2013-01-01

89

Tested Demonstrations.  

ERIC Educational Resources Information Center

This article details two demonstrations involving color changes. Included are "Manganese Color Reactions" and "Flame Colors Demonstration." Include a list of materials needed, procedures, cautions, and results. (CW)

Gilbert, George L., Ed.

1988-01-01

90

Tested Demonstrations.  

ERIC Educational Resources Information Center

Background information (including chemical reactions) and procedures used are provided for (1) three buffer demonstrations and (2) a demonstration of phase transfer catalysis and carbanion formation. (JN)

Gilbert, George L., Ed.

1985-01-01

91

Excessive Ovarian Production of Nerve Growth Factor Facilitates Development of Cystic Ovarian Morphology in Mice and Is a Feature of Polycystic Ovarian Syndrome in Humans  

PubMed Central

Although ovarian nerve growth factor (NGF) facilitates follicular development and ovulation, an excess of the neurotrophin in the rodent ovary reduces ovulatory capacity and causes development of precystic follicles. Here we show that ovarian NGF production is enhanced in patients with polycystic ovarian syndrome (PCOS) and that transgenically driven overproduction of NGF targeted to the ovary results in cystic morphology, when accompanied by elevated LH levels. NGF levels are increased in the follicular fluid from PCOS ovaries and in the culture medium of granulosa cells from PCOS patients, as compared with non-PCOS patients. Ovaries from transgenic mice carrying the NGF gene targeted to thecal-interstitial cells by the 17?-hydroxylase gene promoter produce more NGF than wild-type (WT) ovaries and are hyperinnervated by sympathetic nerves. Antral follicle growth is arrested resulting in accumulation of intermediate size follicles, many of which are apoptotic. Peripubertal transgenic mice respond to a gonadotropin challenge with a greater increase in plasma 17-hydroxyprogesterone, estradiol, and testosterone levels than WT controls. Transgenic mice also exhibit a reduced ovulatory response, delayed puberty, and reduced fertility, as assessed by a prolonged interval between litters, and a reduced number of pups per litter. Sustained, but mild, elevation of plasma LH levels results in a heightened incidence of ovarian follicular cysts in transgenic mice as compared with WT controls. These results suggest that overproduction of ovarian NGF is a component of polycystic ovarian morphology in both humans and rodents and that a persistent elevation in plasma LH levels is required for the morphological abnormalities to appear.

Dissen, Gregory A.; Garcia-Rudaz, Cecilia; Paredes, Alfonso; Mayer, Christine; Mayerhofer, Artur; Ojeda, Sergio R.

2009-01-01

92

Humanized Mice Recapitulate Key Features of HIV1 Infection: A Novel Concept Using Long-Acting AntiRetroviral Drugs for Treating HIV1  

Microsoft Academic Search

BackgroundHumanized mice generate a lymphoid system of human origin subsequent to transplantation of human CD34+ cells and thus are highly susceptible to HIV infection. Here we examined the efficacy of antiretroviral treatment (ART) when added to food pellets, and of long-acting (LA) antiretroviral compounds, either as monotherapy or in combination. These studies shall be inspiring for establishing a gold standard

Marc Nischang; Roger Sutmuller; Gustavo Gers-Huber; Annette Audigé; Duo Li; Mary-Aude Rochat; Stefan Baenziger; Ursula Hofer; Erika Schlaepfer; Stephan Regenass; Katie Amssoms; Bart Stoops; Anja Van Cauwenberge; Daniel Boden; Guenter Kraus; Roberto F. Speck

2012-01-01

93

Tested Demonstrations  

ERIC Educational Resources Information Center

Three demonstrations are described: paramagnetic properties of Fe(11) and Fe(111), the preparation of polyurethane foam: a lecture demonstration and the electrolysis of water-fuel cell reactions. A small discussion of the concepts demonstrated is included in each demonstration's description. (MR)

Gilbert, George L., Ed.

1977-01-01

94

Tested Demonstrations.  

ERIC Educational Resources Information Center

Presents: (1) a simple demonstration which illustrates the driving force of entropy using the familiar effects of the negative thermal expansion coefficient of rubber; and (2) a demonstration of tetrahedral bonding using soap films. (CS)

Gilbert, George L., Ed.

1981-01-01

95

Tested Demonstrations.  

ERIC Educational Resources Information Center

Describes two demonstrations for college level chemistry courses including: "Electrochemical Cells Using Sodium Silicate" and "A Simple, Vivid Demonstration of Selective Precipitation." Lists materials, preparation, procedures, and precautions. (CW)

Gilbert, George L., Ed.

1988-01-01

96

Tested Demonstrations.  

ERIC Educational Resources Information Center

Presents two demonstrations; one on Boyle's Law, to illustrate the gas law and serve as a challenging problem for the students; the other is a modified Color Blind Traffic Light demonstration in which the oscillating reactions were speeded up. (GA)

Gilbert, George L., Ed.

1978-01-01

97

Tested Demonstrations.  

ERIC Educational Resources Information Center

Presented are two demonstrations including a variation of the iodine clock reaction, and a simple demonstration of refractive index. The materials, procedures, and a discussion of probable results are given for each. (CW)

Gilbert, George L., Ed.

1989-01-01

98

Tested Demonstrations.  

ERIC Educational Resources Information Center

Provides instructions on conducting four demonstrations for the chemistry classroom. Outlines procedures for demonstrations dealing with coupled oscillations, the evaporation of liquids, thioxanthone sulfone radical anion, and the control of variables and conservation of matter. (TW)

Gilbert, George L., Ed.

1987-01-01

99

Tested Demonstrations.  

ERIC Educational Resources Information Center

Two demonstrations are described: (1) red cabbage and electrolysis of water to bring together acid/base and electrochemical concepts; and (2) a model to demonstrate acid/base conjugate pairs utilizing magnets. (SK)

Gilbert, George L., Ed.

1981-01-01

100

Tested Demonstrations.  

ERIC Educational Resources Information Center

Procedures for two demonstrations are provided. The solubility of ammonia gas in water is demonstrated by introducing water into a closed can filled with the gas, collapsing the can. The second demonstration relates scale of standard reduction potentials to observed behavior of metals in reactions with hydrogen to produce hydrogen gas. (Author/JN)

Sands, Robert; And Others

1982-01-01

101

Demonstrating Diffusion  

ERIC Educational Resources Information Center

Two demonstrations are described. Materials and instructions for demonstrating movement of molecules into cytoplasm using agar blocks, phenolphthalein, and sodium hydroxide are given. A simple method for demonstrating that the rate of diffusion of a gas is inversely proportional to its molecular weight is also presented. (AJ)

Foy, Barry G.

1977-01-01

102

Tested Demonstrations.  

ERIC Educational Resources Information Center

Describes two classroom chemistry demonstrations which focus on the descriptive chemistry of bromine and iodine. Outlines the chemicals and equipment needed, experimental procedures, and discussion of one demonstration of the oxidation states of bromine and iodine, and another demonstration of the oxidation states of iodine. (TW)

Gilbert, George L., Ed.

1987-01-01

103

Tested Demonstrations.  

ERIC Educational Resources Information Center

List of materials needed, procedures used, and results obtained are provided for two demonstrations. The first is an inexpensive and quick method for demonstrating column chromatography of plant pigments of spinach extract. The second is a demonstration of cathodic protection by impressed current. (JN)

Gilbert, George L., Ed.

1985-01-01

104

Mice Exposed to Chronic Intermittent Hypoxia Simulate Clinical Features of Deficiency of both Qi and Yin Syndrome in Traditional Chinese Medicine  

Microsoft Academic Search

Deficiency of both Qi and Yin Syndrome (DQYS) is one of the common syndromes in trad- itional Chinese medicine (TCM), mainly characterized by tiredness, emaciation, anorexia, fidget, palpitation and rapid pulse, etc. Currently, there is no available animal model which can reflect the clinical features of this syndrome. In the present paper, we observed the time-course changes of whole behavior,

Chengzhi Chai; Junping Kou; Danni Zhu; Yongqing Yan; Boyang Yu

2010-01-01

105

Tested Demonstrations.  

ERIC Educational Resources Information Center

Discusses the photochromic behavior of mercury(II) bis(dithizonate) in providing a colorful demonstration of the effect that visible light can have on the conformation and bonding of molecules in solution. Provides a description of the demonstration itself, along with the preparation needed to complete it. (TW)

Gilbert, George L., Ed.

1986-01-01

106

Tested Demonstrations.  

ERIC Educational Resources Information Center

Describes two laboratory demonstrations in chemistry. One uses dry ice, freon, and freezer bags to demonstrate volume changes, vapor-liquid equilibrium, a simulation of a rain forest, and vaporization. The other uses the clock reaction technique to illustrate fast reactions and kinetic problems in releasing carbon dioxide during respiration. (TW)

Gilbert, George L., Ed.

1987-01-01

107

Tested Demonstrations.  

ERIC Educational Resources Information Center

Background information and procedures are provided for a second part to the dichromate volcano demonstration. The green ash produced during the demonstration is reduced to metal using aluminothermy (Goldschmide process). Also describes suitable light sources and spectroscopes for student observation of emission spectra in lecture halls. (JN)

Gilbert, George L., Ed.

1984-01-01

108

Tested Demonstrations.  

ERIC Educational Resources Information Center

Presented are three demonstrations: "The Construction and Use of Commercial Voltaic Cell Displays in Freshman Chemistry"; Dramatizing Isotopes: Deuterated Ice Cubes Sink"; and "A Simple Apparatus to Demonstrate Differing Gas Diffusion Rates (Graham's Law)." Materials, procedures, and safety considerations are discussed. (CW)

Gilbert, George L., Ed.

1990-01-01

109

Tested Demonstrations.  

ERIC Educational Resources Information Center

Describes a lecture demonstration of a solid state phase transition using a thermodynamic material which changes state at room temperature. Also describes a demonstration on kinetics using a "Big Bang" (trade mark) calcium carbide cannon. Indicates that the cannon is safe to use. (JN)

Gilbert, George L., Ed.

1983-01-01

110

Interactive Demonstrations  

NSDL National Science Digital Library

This website contains general astronomy and astrophysical simulations. Lunar phases, coordinate conversion, Planck spectrum, energy levels, Kepler's laws, and the evolution of a star cluster are demonstrations under the general astronomy section. Astrophysical demonstrations include: effective potential and integrated motion, planet stability in a binary star systems, a disk galaxy, stellar models and spectra, and nuclear isotope stability.

Tomley, Les

2004-07-13

111

Tested Demonstrations.  

ERIC Educational Resources Information Center

Outlines a simple, inexpensive way of demonstrating electroplating using the reaction between nickel ions and copper metal. Explains how to conduct a demonstration of the electrolysis of water by using a colored Na2SO4 solution as the electrolyte so that students can observe the pH changes. (TW)

Gilbert, George L., Ed.

1986-01-01

112

Tested Demonstrations.  

ERIC Educational Resources Information Center

Discusses a supplement to the "water to rose" demonstration in which a pink color is produced. Also discusses blood buffer demonstrations, including hydrolysis of sodium bicarbonate, simulated blood buffer, metabolic acidosis, natural compensation of metabolic acidosis, metabolic alkalosis, acidosis treatment, and alkalosis treatment. Procedures…

Gilbert, George L., Ed.

1983-01-01

113

Tested Demonstrations.  

ERIC Educational Resources Information Center

Described are demonstrations designed to reveal the important "nonsolvent" properties of water through its interaction with a toy called "Magic Sand" and other synthetic silica derivatives, especially those bonded with organic moities. The procedures for seven demonstrations along with a discussion of the effects are presented. (CW)

Gilbert, George L., Ed.

1990-01-01

114

Tested Demonstrations.  

ERIC Educational Resources Information Center

Presents two demonstrations for classroom use related to precipitation of ferrous hydroxide and to variation of vapor pressure with temperature. The former demonstration is simple and useful when discussing solubility of ionic compounds electrode potential of transition elements, and mixed valence compounds. (Author/SA)

Gilbert, George L., Ed.

1979-01-01

115

Science demonstrations  

NASA Technical Reports Server (NTRS)

Three demonstrations of scientific concepts concerning liquids were performed during the Apollo-Soyuz Test Project mission. Chemical foaming, spreading of liquids, and capillary wicking were the subjects of each demonstration photographed in space. The results clearly illustrated the basic principles, and films suitable for educational uses are now available from the first author.

Snyder, R. S.; Clifton, K. S.; Facemire, B.; Whitaker, A. F.; Grodska, P. G.; Bourgeois, S.

1976-01-01

116

Tested Demonstrations.  

ERIC Educational Resources Information Center

Describes two demonstrations designed to help chemistry students visualize certain chemical properties. One experiment uses balloons to illustrate the behavior of gases under varying temperatures and pressures. The other uses a makeshift pea shooter and a commercial model to demonstrate atomic structure and the behavior of high-speed particles.…

Gilbert, George L., Ed.

1986-01-01

117

Tested Demonstrations.  

ERIC Educational Resources Information Center

Free radical chlorination of methane is used in organic chemistry to introduce free radical/chain reactions. In spite of its common occurrence, demonstrations of the reaction are uncommon. Therefore, such a demonstration is provided, including background information, preparation of reactants/reaction vessel, introduction of reactants, irradiation,…

Gilbert, George L., Ed.

1983-01-01

118

Complete Demonstration.  

ERIC Educational Resources Information Center

Describes four-step approach to educational demonstration: tell learners they will have to perform; what they should notice; describe each step before doing it; and require memorization of steps. Examples illustrate use of this process to demonstrate a general mental strategy, and industrial design, supervisory, fine motor, and specific…

Yelon, Stephen; Maddocks, Peg

1986-01-01

119

Tested Demonstrations.  

ERIC Educational Resources Information Center

Reports two electrochemical demonstrations. Uses a hydrogen-oxygen fuel cell to power a clock. Includes description of methods and materials. Investigates the "potato clock" used with different fruits. Lists emf and current for various fruit and electrode combinations. (ML)

Roffia, Sergio; And Others

1988-01-01

120

Tested Demonstrations.  

ERIC Educational Resources Information Center

Included are three demonstrations that include the phase change of ice when under pressure, viscoelasticity and colloid systems, and flame tests for metal ions. The materials, procedures, probable results, and applications to real life situations are included. (KR)

Gilbert, George L.

1990-01-01

121

Tested Demonstrations.  

ERIC Educational Resources Information Center

Presents three demonstrations suitable for undergraduate chemistry classes. Focuses on experiments with calcium carbide, the induction by iron of the oxidation of iodide by dichromate, and the classical iodine clock reaction. (ML)

Gilbert, George L., Ed.

1987-01-01

122

Tested Demonstrations.  

ERIC Educational Resources Information Center

Presented is a Corridor Demonstration which can be set up in readily accessible areas such as hallways or lobbies. Equipment is listed for a display of three cells (solar cells, fuel cells, and storage cells) which develop electrical energy. (CS)

Gilbert, George L., Ed.

1980-01-01

123

Earthquake Demonstration  

NSDL National Science Digital Library

This demonstration uses an "earthquake machine" constructed from bricks, sand paper, and a winch, to simulate the buildup of elastic strain energy prior to a seismic event and the release of that energy during an earthquake.

124

Kinetic Demonstration.  

ERIC Educational Resources Information Center

Presents a unit on chemical reaction kinetics that consists of a predemonstration activity, the demonstration, and a set of postdemonstration activities that help students transfer the concepts to actual chemical reactions. Simulates various aspects of chemical reaction kinetics. (JRH)

Burgardt, Erik D.; Ryan, Hank

1996-01-01

125

Tested Demonstrations.  

ERIC Educational Resources Information Center

Presents a recipe for the Nylon Rope Trick, which is considered to be one of the most spectacular demonstrations in chemistry. Materials for growing the polymer and some safety precautions are given. (SA)

Gilbert, George L., Ed.

1979-01-01

126

Immunological features and efficacy of a multi-epitope vaccine CTB-UE against H. pylori in BALB/c mice model.  

PubMed

Epitope vaccine is a promising option for prophylactic and therapeutic vaccination against Helicobacter pylori infection. Urease is an essential virulence factor and colonization factor for H. pylori. In this study, we constructed a multi-epitope vaccine named CTB-UE with mucosal adjuvant cholera toxin B subunit (CTB) and tandem copies of Th and B cell epitopes from H. pylori urease A and B subunits. The immunogenicity, specificity, ability to induce neutralizing antibodies against H. pylori urease, and prophylactic and therapeutic efficacy of the CTB-UE vaccine were evaluated in BALB/c mice model after purification. The experimental results indicated that CTB-UE could induce comparatively high levels of specific antibodies against native H. pylori urease, UreA, UreB, or the selected B cell epitopes UreA??????? and UreB??????? involved with the active site of urease and showed an effectively inhibitory effect on the enzymatic activity of urease. Besides, oral prophylactic or therapeutic immunization with CTB-UE significantly decreased H. pylori colonization compared with oral immunization with rUreB or PBS, and the protection was correlated with antigen-specific CD4? T cells and IgG, IgA, and mucosal sIgA antibody responses. This CTB-UE vaccine may be a promising vaccine candidate for the control of H. pylori infection. PMID:24370888

Guo, Le; Yin, Runting; Liu, Kunmei; Lv, Xiaobo; Li, Yonghong; Duan, Xiangguo; Chu, Yuankui; Xi, Tao; Xing, Yingying

2014-04-01

127

Isolation, purification, and structural features of a polysaccharide from Phellinus linteus and its hypoglycemic effect in alloxan-induced diabetic mice.  

PubMed

Phellinus linteus is a medicinal mushroom that has been used in Oriental countries for centuries for its antitumor, antioxidant, immunomodulatory, and biological activity on hyperglycemia. A water-soluble crude polysaccharide was extracted using hot water from P. linteus mycelia grown under submerged culture. An orthogonal experiment was used to optimize the extraction conditions of P. linteus mycelia polysaccharides (PLP). The crude polysaccharide was purified using DEAE Sephadex A-50 and Sephadex G-200 chromatography. Fourier transform infrared (FT-IR) spectroscopy and nuclear magnetic resonance ((1) H NMR) spectroscopy were used to investigate the structure of the purified P. linteus polysaccharide (PLP-I), revealing that it was mainly a branched-type glycan with both ?- and ?-linkages and a pyranoid sugar ring conformation. PLP orally administered at 100 mg/kg body weight/d could significantly reduce the blood glucose level by 35.60% in alloxan-induced diabetic mice. The results of an oral glucose tolerance test (OGTT) revealed that PLP had an effect on glucose disposal after 28 d of treatment. The result revealed that PLP from a submerged culture of P. linteus mycelia possessed potent hypoglycemic properties. The polysaccharide may be useful as a functional food additive and a hypoglycemic agent. PMID:24761950

Zhao, Chao; Liao, Zunsheng; Wu, Xiaoqi; Liu, Yanling; Liu, Xiaoyan; Lin, Zhanxi; Huang, Yifan; Liu, Bin

2014-05-01

128

Physics Demonstrations  

NSDL National Science Digital Library

The teaching of physics is clearly enhanced by the use of demonstrations. Visual examples of abstract concepts aid immeasurably in their mastery. They also provide an opportunity to illustrate the scientific method and to teach the student to relate experimental observation to scientific theory. Experiments represent the means by which scientific knowledge has advanced so rapidly in modern times. Finally, not to be underestimated, the use of demonstrations makes the learning of physics much more enjoyable! This book is a compilation of many of the demonstrations that have been used at the University of Wisconsin - Madison in the teaching of elementary physics over the years as well as a number of demonstrations that I have developed for use in a series of popular lectures, "The Wonders of Physics," aimed at the general public and children in particular. Included also are a number of demonstrations that have been suggested and used by friends or colleagues. All of the demonstrations have been thoroughly tested in a classroom setting or before an audience of the general public.

Sprott, Julien

2009-05-20

129

Tested Demonstrations.  

ERIC Educational Resources Information Center

Describes two demonstrations for use in chemistry instruction. The first illustrates the preparation of a less common oxide of iron, showing why this oxide is rare. The second is an explosion reaction of hydrogen and oxygen that is recommended for use as an attention-getting device. (TW)

Gilbert, George L., Ed.

1987-01-01

130

Tested Demonstrations.  

ERIC Educational Resources Information Center

Two demonstrations are described. The first shows the effect of polarity on solubility. The second is based on the unexpected formation of a precipitate of barium nitrate when barium carbonate or barium phosphate is treated with dilute nitric acid. List of materials needed and procedures used are included. (JN)

Gilbert, George L., Ed.

1984-01-01

131

Tested Demonstrations.  

ERIC Educational Resources Information Center

An apparatus is described in which effects of pressure, volume, and temperature changes on a gas can be observed simultaneously. Includes use of the apparatus in demonstrating Boyle's, Gay-Lussac's, and Charles' Laws, attractive forces, Dalton's Law of Partial pressures, and in illustrating measurable vapor pressures of liquids and some solids.…

Gilbert, George L.

1983-01-01

132

Tested Demonstrations.  

ERIC Educational Resources Information Center

Describes two demonstrations: 1) the effect of polarity on solubility using sodium dichromate, TTE, ligroin, and water to form nonpolar-polar-nonpolar layers with the polar layer being colored; 2) determination of egg whites to be yellow by determining the content of yellow colored riboflavin in the egg white. (MVL)

Cliche, Jean-Marie; And Others

1988-01-01

133

Tested Demonstrations.  

ERIC Educational Resources Information Center

Background information, procedures, and typical results obtained are provided for two demonstrations. The first involves the colorful complexes of copper(II). The second involves reverse-phase separation of Food, Drug, and Cosmetic (FD & C) dyes using a solvent gradient. (JN)

Gilbert, George L., Ed.

1985-01-01

134

Tested Demonstrations.  

ERIC Educational Resources Information Center

Provides instructions and a list of materials needed to demonstrate: (1) a model of the quantum mechanical atom; (2) principles involved in metal corrosion and in the prevention of this destructive process by electrochemical means; and (3) a Thermit reaction, modified to make it more dramatic and interesting for students. (SK)

Gilbert, George L., Ed.

1981-01-01

135

Tested Demonstrations.  

ERIC Educational Resources Information Center

Describes two demonstrations that require almost no preparation time, are visually stimulating, and present a variety of material for class discussion (with sample questions provided). The first involves a sodium bicarbonate hydrochloric acid volcano; the second involves a dissolving polystyrene cup. Procedures used and information on…

Gilbert, George L., Ed.

1985-01-01

136

Tested Demonstrations.  

ERIC Educational Resources Information Center

Describes two demonstrations to illustrate characteristics of substances. Outlines a method to detect the changes in pH levels during the electrolysis of water. Uses water pistols, one filled with methane gas and the other filled with water, to illustrate the differences in these two substances. (TW)

Gilbert, George L., Ed.

1987-01-01

137

Feature Indeterminacy and Feature Resolution.  

ERIC Educational Resources Information Center

Presents a theory of feature representation that accounts for feature indeterminacy and feature resolution within the lexical functional grammar (LFG) framework. The representations discussed, together with minimal extensions of LFG's description language, enable a simple and intuitive characterization of both these phenomena. (Author/VWL)

Dalrymple, Mary; Kaplan, Ronald M.

2000-01-01

138

Inflammatory dilated cardiomyopathy in Abcg5-deficient mice.  

PubMed

Dilated cardiomyopathy (DCM) in A/J mice homozygous for the spontaneous thrombocytopenia and cardiomyopathy (trac) mutation results from a single base pair change in the Abcg5 gene. A similar mutation in humans causes sitosterolemia with high plant sterol levels, hypercholesterolemia, and early onset atherosclerosis. Analyses of CD3+ and Mac-3+ cells and stainable collagen in hearts showed inflammation and myocyte degeneration in A/J-trac/trac mice beginning postweaning and progressed to marked dilative and fibrosing cardiomyopathy by 140 days. Transmission electron microscopy (TEM) demonstrated myocyte vacuoles consistent with swollen endoplasmic reticulum (ER). Myocytes with cytoplasmic glycogen and irregular actinomyosin filament bundles formed mature intercalated disks with normal myocytes suggesting myocyte repair. A/J-trac/trac mice fed lifelong phytosterol-free diets did not develop cardiomyopathy. BALB/cByJ-trac/trac mice had lesser inflammatory infiltrates and later onset DCM. BALB/cByJ-trac/trac mice changed from normal to phytosterol-free diets had lesser T cell infiltrates but persistent monocyte infiltrates and equivalent fibrosis to mice on normal diets. B- and T-cell-deficient BALB/cBy-Rag1(null) trac/trac mice fed normal diets did not develop inflammatory infiltrates or DCM. We conclude that the trac/trac mouse has many features of inflammatory DCM and that the reversibility of myocardial T cell infiltration provides a novel model for investigating the progression of myocardial fibrosis. PMID:23129576

Wilson, Dennis W; Oslund, Karen L; Lyons, Bonnie; Foreman, Oded; Burzenski, Lisa; Svenson, Karen L; Chase, Thomas H; Shultz, Leonard D

2013-08-01

139

Inflammatory Dilated Cardiomyopathy in Abcg5 Deficient Mice  

PubMed Central

Dilated cardiomyopathy (DCM) in A/J mice homozygous for the spontaneous thrombocytopenia and cardiomyopathy (trac) mutation results from a single base pair change in the Abcg5 gene. A similar mutation in humans causes sitosterolemia with high plant sterol levels, hypercholesterolemia, and early onset atherosclerosis. Analyses of CD3+ and Mac-3+ cells and trichrome stainable collagen in hearts showed inflammation and myocyte degeneration in A/J-trac/trac mice beginning post-weaning and progressed to marked dilative and fibrosing cardiomyopathy by 140 days. TEM demonstrated myocyte vacuoles consistent with swollen ER. Myocytes with abundant cytoplasmic glycogen and less dense actinomyosin filament bundles formed mature intercalated discs with adjacent normal myocytes suggesting myocyte repair. A/J-trac/trac mice fed life long phytosterol-free diets did not develop cardiomyopathy. BALB/cByJ- trac/trac mice had lesser inflammatory infiltrates and later onset DCM. BALB/cByJ- trac/trac mice changed from normal to phytosterol-free diets after initiation of cadiomyopathy had lesser T cell infiltrates but persistent monocyte infiltrates and equivalent fibrosis to mice on normal diets. B and T cell deficient BALB/cBy-Rag1null trac/trac mice fed normal diets did not develop inflammatory infiltrates or DCM. We conclude that DCM in the trac/trac mouse shares many features of inflammatory DCM and that the reversibility of myocardial T cell infiltration provides a novel model for investigating the progression of myocardial fibrosis.

Wilson, Dennis W.; Oslund, Karen L.; Lyons, Bonnie; Foreman, Oded; Burzenski, Lisa; Svenson, Karen L.; Chase, Thomas H.; Shultz, Leonard D.

2014-01-01

140

[Elimination from the digestive tract of a "gnotoxenic" child of a "Lactobacillus casei" strain, isolated from a commercial preparation: antagonistic effect of an "Escherichia coli" strain of human origin, demonstrated in "gnotoxenic" mice (author's transl)].  

PubMed

A strain of Lactobacillus casei from a pharmaceutical preparation became established in the digestive tract of an axenic child. It was eliminated by the first bacteria occurring after inoculation of the child's digestive tract with a human flora, before the child was taken out of the isolator. Using "gnotoxenic" mice, we found that the elimination of L. casei was due to a bactericidal effect of the Escherichia coli of human origin, within the digestive tract. PMID:828463

Hudault, S; Ducluzeau, R; Dubos, F; Raibaud, P; Ghnassia, J C; Griscelli, C

1976-07-01

141

Emittance measurement in MICE  

NASA Astrophysics Data System (ADS)

Ionisation Cooling will be an essential element of a future Neutrino Factory [1]. The Muon Ionization Cooling Experiment, MICE at RAL (UK), will be the first apparatus to demonstrate this technique. MICE will be unique in making single-particle measurements determining the amplitude of each muon in 6D phase space. It is shown how amplitude measurements can be used to quantify the increase in central phase space density due to cooling.

Apollonio, M.; Cobb, J. H.

2008-05-01

142

Sporadic colon cancer murine models demonstrate the value of autoantibody detection for preclinical cancer diagnosis  

PubMed Central

Although autoantibody detection has been proposed for diagnosis of colorectal cancer, little is known about their initial production and development correlation with cancer progression. Azoxymethane/dextran sodium sulfate (AOM/DSS)-treated mice developed colon adenocarcinoma in the distal colon similar to human sporadic colon cancer. We assessed this model together with AOM and DSS-only models for their applicability to early detection of cancer. All AOM/DSS-treated mice produced autoantibodies to tumor-associated antigens analogous to those observed in human colon cancer patients. Autoantibody response was related to tumor antigen overexpression. Cancer autoantibodies were detected 21 days after starting treatment, when no malignant histopathological features were detectable, and they increased according to tumor progression. When carcinogenesis was induced separately by AOM or DSS, only those mice that developed malignant lesions produced significant levels of autoantibodies. These findings demonstrate that autoantibody development is an early event in tumorigenesis and validates its use for preclinical colon cancer diagnosis.

Barderas, Rodrigo; Villar-Vazquez, Roi; Fernandez-Acenero, Maria Jesus; Babel, Ingrid; Pelaez-Garcia, Alberto; Torres, Sofia; Casal, J. Ignacio

2013-01-01

143

Desert Features  

NSDL National Science Digital Library

Sand covers only about 20 percent of the Earth's deserts. Nearly 50 percent of desert surfaces are gravel plains where removal of fine-grained material by the wind has exposed loose gravel and occasional cobbles. This web page, produced by the U.S. Geological Survey, features text and photographs that describe desert landforms, soils, plants, and the role of water in the formation of desert landscapes.

144

Volcanic Features  

NSDL National Science Digital Library

Most people will never see the eruption of an active volcano. Even so, evidence of these dramatic displays can be found all over the world. In fact, more can be learned about some aspects of volcanic activity by exploring evidence left by past eruptions than by watching an eruption in progress. This interactive resource adapted from the National Park Service explores a variety of volcanic landforms and features, and describes how they form.

2010-10-25

145

Applying assist features to improve two dimensional feature process robustness  

NASA Astrophysics Data System (ADS)

Sub-resolution assist features are an important tool for improving process robustness for one-dimensional pattern features at advanced manufacturing process nodes. However, sub-resolution assist feature development efforts have not generally considered optimization for process robustness with two-dimensional pattern features. This generally arises both from conservatively placing SRAFs to avoid the possibility of imaging, and from a desire to simplify SRAF placement rules. By studying two-dimensional features using a manufacturing sensitivity model, one can gain insight into the capabilities of SRAFs regarding two-dimensional pattern features. These insights suggest new methodologies for shaping assist features to enhance two-dimensional feature robustness. In addition, a manufacturing sensitivity model form can be employed to optimize the placement of multiple competing SRAFs in localized two-dimensional regions. Initial studies demonstrate significant pullback reduction for two-dimensional features once SRAF placement has been optimized using the manufacturing sensitivity model form.

Melvin, Lawrence S., III; Painter, Benjamin D.; Barnes, Levi D.

2005-11-01

146

Cerebral Malaria in Mice  

PubMed Central

In this study, we report that infection with Plasmodium yoelii 17XL, a lethal strain of rodent malaria, does not result in death in the DBA/2 strain of mice. In contrast to BALB/c mice, DBA/2 mice developed significantly less parasitemia and never manifested symptoms of cerebral malaria (CM) on infection with this parasite. Moreover, the histological changes evident in the brain of susceptible BALB/c were absent in DBA/2 mice. Interestingly, the resistant DBA/2 mice when treated with recombinant interleukin (IL)-2, were found to develop CM symptoms and the infection became fatal by 6 to 8 days after infection. This condition was associated with an augmented interferon-? and nitric oxide production. Unexpectedly, IL-10 levels were also elevated in IL-2-treated DBA/2 mice during late stage of infection (at day 6 of infection) whereas the inverse relationship between IL-10 and interferon-? or nitric oxide was maintained in the early stage of infection (at day 3 after infection). The level of tumor necrosis factor-? production was moderately increased in the late phase of infection in these mice. Histology of brain from IL-2-treated mice demonstrated the presence of parasitized erythrocytes and infiltration of lymphocytes in cerebral vessels, and also displayed some signs of endothelial degeneration. Confocal microscopical studies demonstrated preferential accumulation of ?? T cells in the cerebral vessels of IL-2-treated and -infected mice but not in mice treated with IL-2 alone. The cells recruited in the brain were activated because they demonstrated expression of CD25 (IL-2R) and CD54 (intercellular adhesion molecule 1) molecules. Administration of anti-?? mAb prevented development of CM in IL-2-treated mice until day 18 after infection whereas mice treated with control antibody showed CM symptoms by day 6 after infection. The information concerning creating pathological sequelae and death in an otherwise resistant mouse strain provides an interesting focus for the burden of pathological attributes on death in an infectious disease.

Haque, Azizul; Echchannaoui, Hakim; Seguin, Rosanne; Schwartzman, Joseph; Kasper, Lloyd H.; Haque, Sakhina

2001-01-01

147

Partial Return Yoke for MICE  

SciTech Connect

The international Muon Ionization Cooling Experiment (MICE) is a large scale experiment which is presently assembled at the Rutherford Appleton Laboratory in Didcot, UK. The purpose of MICE is to demonstrate the concept of ionization cooling experimentally. Ionization cooling is an important accelerator concept which will be essential for future HEP experiments such as a potential Muon Collider or a Neutrino Factory. The MICE experiment will house up to 18 superconducting solenoids, all of which produce a substantial amount of magnetic flux. Recently it was realized that this magnetic flux leads to a considerable stray magnetic field in the MICE hall. This is a concern as technical equipment in the MICE hall may may be compromised by this. In July 2012 a concept called partial return yoke was presented to the MICE community, which reduces the stray field in the MICE hall to a safe level. This report summarizes the general concept, engineering considerations and the expected shielding performance.

Witte H.; Plate, S; ,

2013-05-03

148

General features  

SciTech Connect

The San Andreas fault system, a complex of faults that display predominantly large-scale strike slip, is part of an even more complex system of faults, isolated segments of the East Pacific Rise, and scraps of plates lying east of the East Pacific Rise that collectively separate the North American plate from the Pacific plate. This chapter briefly describes the San Andreas fault system, its setting along the Pacific Ocean margin of North America, its extent, and the patterns of faulting. Only selected characteristics are described, and many features are left for depictions on maps and figures.

Wallace, R.E.

1990-01-01

149

Demonstration of passive safety features in EBR-II  

SciTech Connect

Two tests of great importance to the design of future commercial nuclear power plants were carried out in the Experimental Breeder Reactor-II on April 3, 1986. These tests, (viewed by about 60 visitors, including 13 foreign LMR specialists) were a loss of flow without scram and a loss of heat sink without scram, both from 100% initial power. In these tests, inherent feedback shut the reactor down without damage to the fuel or other reactor components. This resulted primarily from advantageous characteristics of the metal driver fuel used in EBR-II. Work is currently underway at EBR-II to develop a control strategy that promotes inherent safety characteristics, including survivability of transient overpower accidents. In parallel, work is underway at EBR-II on the development of state-of-the-art plant diagnostic techniques.

Planchon, H.P. Jr.; Golden, G.H.; Sackett, J.I.

1987-01-01

150

Demonstrational Features of the Tuskegee Institute Retraining Project, Volume I.  

ERIC Educational Resources Information Center

This 52-week Tuskegee Institute project, undertaken in 1964 to train a sample of culturally deprived male heads of households in Alabama, included vocational skills (brickmasonry, carpentry, farm machinery, and meat processing), academic skills (mathematics, English, and remedial reading), group, individual, and family counseling, medical care,…

Tuskegee Inst., AL.

151

Facial features  

NSDL National Science Digital Library

THE STATE STANDARDS for this project are as follows; STANDARD 1 Making: Students will assemble and create works of art by experiencing a variety of art media and by learning the art elements and principles. STANDARD 2 Perceiving: Students will find meaning by analyzing, criticizing, and evaluating works of art. STANDARD 3 Expressing: Students will create meaning in art. STANDARD 4 Contextualizing: Students will find meaning in works of art through settings and other modes of learning. Below is a list of useful site to help in drawing facial features, along with useful tutorial and resources. QUICK TEST (test your ability and knowledge) * Draw a circle. * Draw a light vertical line at the center of the circle. * Make light horizontal dashes a little above the center of the circle. ...

Allan, Mrs.

2008-09-21

152

Passive Transfer of Autoimmune Autonomic Neuropathy to Mice  

PubMed Central

Autoimmune autonomic neuropathy (AAN) is an acquired, often severe, form of dysautonomia. Many patients with AAN have serum antibodies specific for the neuronal ganglionic nicotinic acetylcholine receptor (AChR). Rabbits immunized with a fusion protein corresponding to the N-terminal extracellular domain of the ganglionic AChR ?3 subunit produce ganglionic AChR antibodies and develop signs of experimental AAN (EAAN) that recapitulate the cardinal autonomic features of AAN in man. We now demonstrate that EAAN is an antibody-mediated disorder by documenting sympathetic, parasympathetic, and enteric autonomic dysfunction in mice injected with rabbit IgG containing ganglionic AChR antibodies. Recipient mice develop transient gastrointestinal dysmotility, urinary retention, dilated pupils, reduced heart rate variability, and impaired catecholamine response to stress. The autonomic signs are associated with a reversible failure of nicotinic cholinergic synaptic transmission in superior mesenteric ganglia. Mice injected with IgG from two patients with AAN (of three tested) demonstrated a milder phenotype with evidence of urinary retention and gastrointestinal dysmotility. The demonstration that ganglionic AChR-specific IgG causes impaired autonomic synaptic transmission and autonomic failure in mice implicates an antibody-mediated pathogenesis for AAN. The antibody effect is potentially reversible, justifying early use of immunomodulatory therapy directed at lowering IgG levels and abrogating IgG production in patients with AAN.

Vernino, Steven; Ermilov, Leonid G.; Sha, Lei; Szurszewski, Joseph H.; Low, Phillip A.; Lennon, Vanda A.

2005-01-01

153

The programmers' playground: a demonstration  

Microsoft Academic Search

We demonstrate The Programmers' Playground, a pro- gramming environment that supports end-user con- struction of distributed multimedia applications. Features include separation of communication and computation, dynamic end-user configuration of dis- tributed applications, separation of active & reactive control, and migration of running modules. Applica- tions include a process control simulation, planetary orbits visualization, medical image processing pipe- line, a multimedia

Kenneth J. Goldman; T. Paul McCartney; Ram Sethuraman; Bala Swaminathan

1995-01-01

154

Favorite Demonstration: An Illuminating Catalysis Demonstration  

NSDL National Science Digital Library

The catalase demonstration presented here is a variation of a traditional experiment that is normally run to demonstrate enzyme activity in basic undergraduate biology classes. It is one of the easiest laboratory activities to demonstrate organic catalysis. The setup involves minimum preparation and inexpensive materials (Mader 1995).

Hoots, Rita

2004-02-01

155

Production of transmitochondrial mice  

Microsoft Academic Search

With the advancement of various gene transfer technologies, the establishment of mitochondria transfer as a viable technique to genetically engineer mouse models paradoxically lagged behind other genetic technologies. The lack of demonstrable recombination in mtDNA necessitates different approaches to conventional transgenesis-based techniques. Initially, heteroplasmic mice were created to explore disease pathogenesis and mitochondrial dynamics in an in vivo system. Ultimately,

Carl A. Pinkert; Ian A. Trounce

2002-01-01

156

Mice Rule! (Or Not)  

NSDL National Science Digital Library

Students explore the relationships between genetics, biodiversity, and evolution through a simple activity involving hypothetical wild mouse populations. First, students toss coins to determine what traits a set of mouse parents possesses, such as fur color, body size, heat tolerance, and running speed. Next they use coin tossing to determine the traits a mouse pup born to these parents possesses. These physical features are then compared to features that would be most adaptive in several different environmental conditions. Finally, students consider what would happen to the mouse offspring if those environmental conditions were to change: which mice would be most likely to survive and produce the next generation?

Engineering K-Ph.d. Program

157

Deletion of IL-12p35 induces liver fibrosis in dominant negative transforming growth factor ? receptor type II mice  

PubMed Central

We have previously reported that mice with a dominant negative transforming growth factor ? receptor restricted to T cells (dnTGF?RII mice) develop an inflammatory biliary ductular disease that strongly resembles human primary biliary cirrhosis (PBC). Furthermore, deletion of the gene encoding interleukin (IL)-12p40 resulted in a strain (IL-12p40?/?dnTGF?RII) with dramatically reduced autoimmune cholangitis. To further investigate the role of the IL-12 cytokine family in dnTGF?RII autoimmune biliary disease, we deleted the gene encoding the IL-12p35 subunit from dnTGF?RII mice, resulting in an IL-12p35?/? dnTGF?RII strain which is deficient in two members of the IL-12 family, IL-12 and IL-35. In contrast to IL-12p40?/? mice, the IL-12p35?/? mice developed liver inflammation and bile duct damage with similar severity but delayed onset as the parental dnTGF?RII mice. The p35?/? mice also demonstrated a distinct cytokine profile characterized by a shift from a Th1 to a Th17 response. Strikingly, liver fibrosis was frequently observed in IL-12p35?/? mice. In conclusion, IL-12p35?/? dnTGF?RII mice, histologically and immunologically, reflect key features of PBC, providing a useful generic model to understand the immunopathology of human PBC.

Tsuda, Masanobu; Zhang, Weici; Yang, Guo-Xiang; Tsuneyama, Koichi; Ando, Yugo; Kawata, Kazuhito; Park, Ogyi; Leung, Patrick S.C.; Coppel, Ross L.; Ansari, Aftab A.; Ridgway, William M.; Gao, Bin; Lian, Zhe-Xiong; Flavell, Richard; He, Xiao-Song; Gershwin, M. Eric

2012-01-01

158

Improved establishment of embryonic stem (ES) cell lines from the Chinese Kunming mice by hybridization with 129 mice.  

PubMed

Chinese Kunming mice (Mus musculus Km), widely used as laboratory animals throughout China, remain very refractory for embryonic stem (ES) cell isolation. The present study was aimed to evaluate the effects of hybridization with 129/Sv mice, and culture media containing fetal bovine serum (FBS) or Knockout serum replacement (KSR) on ES cell isolation from Kunming mice. The results demonstrated that ES cells had been effectively isolated from the hybrid embryos of Kunming and 129/Sv mice using all three media containing 15% FBS, 15% KSR and their mixture of 14% KSR and 1% FBS, individually. These isolated ES cells had maintained in vitro undifferentiated for a long time, exhibiting all features specific for mouse ES cells. In addition, the rates of ES cell isolation in the medium containing 14% KSR and 1% FBS, was 46.67% and significantly higher than those in another two media containing only FBS or KSR (p < 0.05). Contrarily, no ES cell line had been established from Kunming mouse inbred embryos using the same protocols. These results suggested that ES cells with long-term self-renewal ability could be efficiently generated from hybrid embryos of Kunming and 129/Sv mice, and a small volume of FBS was necessary to isolate ES cells in the KSR medium when embryos and early ES cells cultured. PMID:24573251

Yu, Shumin; Yan, Xingrong; Liu, Huanhuan; Cai, Xin; Cao, Suizhong; Shen, Liuhong; Zuo, Zhicai; Deng, Junliang; Ma, Xiaoping; Wang, Ya; Ren, Zhihua

2014-01-01

159

TLR5-deficient mice lack basal inflammatory and metabolic defects but exhibit impaired CD4 T cell responses to a flagellated pathogen  

PubMed Central

TLR5-deficient mice have been reported to develop spontaneous intestinal inflammation and metabolic abnormalities. However, we report that TLR5-deficient mice from two different animal colonies display no evidence of basal inflammatory disease, metabolic abnormalities, or enhanced resistance to Salmonella infection. In contrast, the absence of TLR5 hindered the initial activation and clonal expansion of intestinal flagellin-specific CD4 T cells following oral Salmonella infection. Together, these data demonstrate that a basal inflammatory phenotype is not a consistent feature of TLR5-deficient mice, and document a novel role for TLR5 in the rapid targeting of flagellin by intestinal pathogen-specific CD4 T cells.

Letran, Shirdi E.; Lee, Seung-Joo; Atif, Shaikh M.; Flores-Langarica, Adriana; Uematsu, Satoshi; Akira, Shizuo; Cunningham, Adam F.; McSorley, Stephen J.

2014-01-01

160

Advanced servomanipulator remote maintenance demonstration  

SciTech Connect

The Fuel Recycle Division (FRD) of the Oak Ridge National Laboratory (ORNL) is developing remote maintenance systems for the Consolidated Fuel Reprocessing Program for applications in future nuclear fuel cycle facilities. The most recent development is the advanced servomanipulator (ASM), a digitally controlled, force-reflecting, dual-arm, master/slave servomanipulator. A unique feature of ASM is that the slave arms are remotely maintainable. The ASM slave arms are composed of modules, each of which is capable of being removed and replaced by another manipulator system. The intent of this test was to demonstrate that the ASM slave arms could be completely disassembled and reassembled remotely. This remote maintenance demonstration was performed using the Remote Operations and Maintenance Demonstration (ROMD) facility model M-2 servomanipulator maintenance system. Maintenance of ASM was successfully demonstrated using the M-2 servomanipulator and special fixtures. Recommendations, generally applicable to other remotely maintained equipment, have been made for maintainability improvements. 3 refs., 5 figs.

Bradley, E.C.; Ladd, L.D.

1988-01-01

161

Favorite Demonstration: Demonstrating Allotropic Modifications of Sulfur  

NSDL National Science Digital Library

This demonstration closely simulates Io's surface and validates scientists' conclusions about this satellite of Jupiter. It illustrates the importance of teaching descriptive chemistry and is suitable for a general science class as well as introductory ch

Mccarty, Jillian L.; Dragojlovic, Veljko

2001-12-01

162

Neutral aminoaciduria in cystathionine ?-synthase-deficient mice, an animal model of homocystinuria.  

PubMed

The kidney is one of the major loci for the expression of cystathionine ?-synthase (CBS) and cystathionine ?-lyase (CTH). While CBS-deficient (Cbs(-/-)) mice display homocysteinemia/methioninemia and severe growth retardation, and rarely survive beyond the first 4 wk, CTH-deficient (Cth(-/-)) mice show homocysteinemia/cystathioninemia but develop with no apparent abnormality. This study examined renal amino acid reabsorption in those mice. Although both 2-wk-old Cbs(-/-) and Cth(-/-) mice had normal renal architecture, their serum/urinary amino acid profiles largely differed from wild-type mice. The most striking feature was marked accumulation of Met and cystathionine in serum/urine/kidney samples of Cbs(-/-) and Cth(-/-) mice, respectively. Levels of some neutral amino acids (Val, Leu, Ile, and Tyr) that were not elevated in Cbs(-/-) serum were highly elevated in Cbs(-/-) urine, and urinary excretion of other neutral amino acids (except Met) was much higher than expected from their serum levels, demonstrating neutral aminoaciduria in Cbs(-/-) (not Cth(-/-)) mice. Because the bulk of neutral amino acids is absorbed via a B(0)AT1 transporter and Met has the highest substrate affinity for B(0)AT1 than other neutral amino acids, hypermethioninemia may cause hyperexcretion of neutral amino acids. PMID:24761004

Akahoshi, Noriyuki; Kamata, Shotaro; Kubota, Masashi; Hishiki, Takako; Nagahata, Yoshiko; Matsuura, Tomomi; Yamazaki, Chiho; Yoshida, Yuka; Yamada, Hidenori; Ishizaki, Yasuki; Suematsu, Makoto; Kasahara, Tadashi; Ishii, Isao

2014-06-15

163

Favorite Demonstration: A Fruity Biochemistry Demonstration  

NSDL National Science Digital Library

Inquiry, high-order thinking, reasoning skills, and critical thinking are buzzwords for the outcomes for which college science instructors strive. They can all be succinctly summarized as "get students thinking about what they are learning." Classroom demonstrations are a great vechicle for getting students to apply information they have heard in a lecture. A good example of this type of application is a demonstration that uses simple fruit and vegetable spoilage biochemistry principles to teach scientific reasoning skills.

Shmaefsky, Brian R.

2005-05-01

164

CD8+ TCR Transgenic Strains Expressing Public versus Private TCR Targeting the Respiratory Syncytial Virus KdM282–90 Epitope Demonstrate Similar Functional Profiles  

PubMed Central

Our previous work has characterized the functional and clonotypic features of two respiratory syncytial virus (RSV) epitope-specific T cell responses in mice. Following single-cell sequencing, we selected T cell receptor sequences to represent both a public and a private clone specific for the dominant KdM282–90 epitope for the generation of T cell receptor transgenic (TCR Tg) mice. We evaluated cells from these TCR Tg strains for three major functions of CD8+ T cells: proliferation, cytokine production and cytolytic activity. In vitro comparisons of the functional characteristics of T cells from the newly-generated mice demonstrated many similarities in their responsiveness to cognate antigen stimulation. Cells from both TRBV13-1 (private) and TRBV13-2 (public) TCR Tg mice had similar affinity, and proliferated similarly in vitro in response to cognate antigen stimulation. When transferred to BALB/c mice, cells from both strains demonstrated extensive proliferation in mediastinal lymph nodes following RSV infection, with TRBV13-2 demonstrating better in vivo proliferation. Both strains similarly expressed cytokines and chemokines following stimulation, and had similar Granzyme B and perforin expression, however cells expressing TRBV13-1 demonstrated better cytolytic activity than TRBV13-2 cells. These new, well-characterized mouse strains provide new opportunities to study molecular mechanisms that control the phenotype and function of CD8+ T cell responses.

Malloy, Allison M. W.; Graham, Barney S.; Ruckwardt, Tracy J.

2014-01-01

165

A Fluorescence Lecture Demonstration.  

ERIC Educational Resources Information Center

Describes fluorescence demonstrations related to several aspects of molecular theory and quantitized energy levels. Demonstrations use fluorescent chemical solutions having luminescence properties spanning the visible spectrum. Also describes a demonstration of spontaneous combustion of familiar substances in chlorine. (JN)

Bozzelli, Joseph W.; Kemp, Marwin

1982-01-01

166

Vertical Feature Mask Feature Classification Flag Extraction  

... Level 2 Vertical Feature Mask feature classification flag value. It is written in Interactive Data Language (IDL) as a callable ... receives as an argument a 16-bit feature classification flag value and prints the feature type information extracted from the bits in the ...

2013-03-28

167

Herschel's Interference Demonstration.  

ERIC Educational Resources Information Center

Describes Herschel's demonstration of interference arising from many coherent rays. Presents a method for students to reproduce this demonstration and obtain beautiful multiple-beam interference patterns. (CCM)

Perkalskis, Benjamin S.; Freeman, J. Reuben

2000-01-01

168

Combining Feature Subsets in Feature Selection  

Microsoft Academic Search

\\u000a In feature selection, a part of the features is chosen as a new feature subset, while the rest of the features is ignored.\\u000a The neglected features still, however, may contain useful information for discriminating the data classes. To make use of\\u000a this information, the combined classifier approach can be used. In our paper we study the efficiency of combining applied

Marina Skurichina; Robert P. W. Duin

2005-01-01

169

Characterization of the insulin sensitivity of ghrelin receptor KO mice using glycemic clamps  

Microsoft Academic Search

BACKGROUND: We and others have demonstrated previously that ghrelin receptor (GhrR) knock out (KO) mice fed a high fat diet (HFD) have increased insulin sensitivity and metabolic flexibility relative to WT littermates. A striking feature of the HFD-fed GhrR KO mouse is the dramatic decrease in hepatic steatosis. To characterize further the underlying mechanisms of glucose homeostasis in GhrR KO

Yong Qi; Kenneth A Longo; Derek J Giuliana; Samantha Gagne; Tom McDonagh; Elizabeth Govek; Anna Nolan; Chaoseng Zou; Kristen Morgan; Jeffrey Hixon; Jeffrey O Saunders; Peter S DiStefano; Brad J Geddes

2011-01-01

170

ORION II bus demonstration. Demonstration report (Final)  

SciTech Connect

The Central New York Regional Transportation Authority conducted an 18-month demonstration to determine how the ORION II bus operates in actual service. The ORION II vehicle is a small low floor, accessible heavy duty, diesel-powered transit bus designed to meet the needs of the elderly and handicapped. It has the capacity to seat 26 passengers with 4 wheelchair lockdowns. Side and rear doors are equipped with electrically powered ramps. Eight Thomas vehicles (22-foot, 11,500 lbs, wheelchair equipped, gasoline fueled) were also tested during the demonstration period. Operations (fuel and oil usage) and maintenance (scheduled and unscheduled) data were collected and charted-out in the report as well as driver, passenger, and maintenance surveys. This report provides descriptions, photographs, and comparison charts of both the diesel-fueled ORION II transit bus and the gasoline-fueled Thomas vehicles along with the demonstration test plan, evaluations, conclusions, and survey results.

Shanley, J.

1989-02-01

171

Why Demonstrations Matter  

ERIC Educational Resources Information Center

With the current focus on constructivist perspectives, science demonstrations have fallen out of favor in some circles. Demonstrations are easy to do and offer many benefits and unique opportunities in the constructivist classroom. With careful use, demonstrations can be powerful teaching tools. A wonderful quality of a demonstration (or a series…

Black, Richard

2005-01-01

172

Favorite Demonstration: An Inexpensive Resonance Demonstration  

NSDL National Science Digital Library

Resonance is commonplace and easy to recognize when it occurs. Yet it is also one of the most impressive and often unexpected phenomenon in all of physics. This article describes a visually appealing resonance demonstrator that uses readily available and inexpensive parts.

Dukes, Phillip

2005-01-01

173

The MICE Muon Beam Line  

SciTech Connect

In the Muon Ionization Cooling Experiment (MICE) at RAL, muons are produced and transported in a dedicated beam line connecting the production point (target) to the cooling channel. We discuss the main features of the beamline, meant to provide muons with momenta between 140 MeV/c and 240 MeV/c and emittances up to 10 mm rad, which is accomplished by means of a diffuser. Matching procedures to the MICE cooling channel are also described. In summer 2010 we performed an intense data taking campaign to finalize the calibration of the MICE Particle Identification (PID) detectors and the understanding of the beam line, which completes the STEPI phase of MICE. We highlight the main results from these data.

Apollonio, Marco [High Energy Physics Group, Department of Physics, Imperial College London SW7 2AZ (United Kingdom)

2011-10-06

174

The MICE Muon Beam Line  

NASA Astrophysics Data System (ADS)

In the Muon Ionization Cooling Experiment (MICE) at RAL, muons are produced and transported in a dedicated beam line connecting the production point (target) to the cooling channel. We discuss the main features of the beamline, meant to provide muons with momenta between 140 MeV/c and 240 MeV/c and emittances up to 10 mm rad, which is accomplished by means of a diffuser. Matching procedures to the MICE cooling channel are also described. In summer 2010 we performed an intense data taking campaign to finalize the calibration of the MICE Particle Identification (PID) detectors and the understanding of the beam line, which completes the STEPI phase of MICE. We highlight the main results from these data.

Apollonio, Marco

2011-10-01

175

Overhead Projector Demonstrations.  

ERIC Educational Resources Information Center

Describes several chemistry demonstrations that use an overhead projector. Some of the demonstrations deal with electrochemistry, and another deals with the reactions of nonvolatile immiscible liquid in water. (TW)

Kolb, Doris, Ed.

1987-01-01

176

Polarized Light Corridor Demonstrations.  

ERIC Educational Resources Information Center

Eleven demonstrations of light polarization are presented. Each includes a brief description of the apparatus and the effect demonstrated. Illustrated are strain patterns, reflection, scattering, the Faraday Effect, interference, double refraction, the polarizing microscope, and optical activity. (CW)

Davies, G. R.

1990-01-01

177

Infant CPR Video Demonstration  

MedlinePLUS

Infant CPR Video Demonstration Video demonstration of CPR instruction for infants. RETURN TO MAIN PAGE These Videos Are For Educational Use Only And Are Not Authorized for Commercial Use. © 1998 - 2011 ...

178

Cardio Lab Powerpoint Demonstration  

NSDL National Science Digital Library

Powerpoint presentation utilizing a Functional Heart Model to demonstrate the relationships among stroke volume, heart rate, and cardiac output. Demonstration also includes blood vessel radius and flow-pressure relationships. Oxygen consumption and VO2 MAX is discussed.

Ms. Jeannette K Hafey (Springfield College Biology/Chemistry)

2010-05-24

179

Exosomes from bronchoalveolar fluid of tolerized mice prevent allergic reaction.  

PubMed

Exosomes are nanovesicles originating from multivesicular bodies that are secreted by a variety of cell types. The dual capability of exosomes to promote immunity or to induce tolerance has prompted their clinical use as vehicles for vaccination against different human diseases. In the present study, the effect of allergen-specific exosomes from tolerized mice on the development of allergen-induced allergic response was determined using a mouse model. Mice were tolerized by respiratory exposure to the olive pollen allergen Ole e 1. Exosome-like vesicles were isolated from bronchoalveolar lavage fluid of the animals by the well-established filtration and ultracentrifugation procedure, characterized by electron microscopy, Western blot, and FACS analyses, and assessed in a prophylactic protocol. To this end, BALB/c mice were intranasally treated with tolerogenic exosomes or naive exosomes as control, 1 wk before sensitization/challenge to Ole e 1. Blood, lungs, and spleen were collected and analyzed for immune responses. Intranasal administration of tolerogenic exosomes inhibited the development of IgE response, Th2 cytokine production, and airway inflammation--cardinal features of allergy--and maintained specific long-term protection in vivo. This protective effect was associated with a concomitant increase in the expression of the regulatory cytokine TGF-beta. These observations demonstrate that exosomes can induce tolerance and protection against allergic sensitization in mice. Thus, exosome-based vaccines could represent an alternative to conventional therapy for allergic diseases in humans. PMID:18606707

Prado, Noela; Marazuela, Eva G; Segura, Elodie; Fernández-García, Héctor; Villalba, Mayte; Théry, Clotilde; Rodríguez, Rosalía; Batanero, Eva

2008-07-15

180

Classroom Demonstrations: Individual Differences.  

ERIC Educational Resources Information Center

These demonstrations stress individual differences, a concept becoming increasingly important in psychological research. Intended for use in undergraduate psychology courses, four demonstrations that illustrate common examples of human variation are described. The demonstrations deal with the following individual differences: taste blindness,…

Singer, Sandra M.

181

Overhead Projector Demonstrations.  

ERIC Educational Resources Information Center

Details two demonstrations for use with an overhead projector in a chemistry lecture. Includes "A Very Rapidly Growing Silicate Crystal" and "A Colorful Demonstration to Simulate Orbital Hybridization." The materials and directions for each demonstration are included as well as a brief explanation of the essential learning involved. (CW)

Kolb, Doris, Ed.

1988-01-01

182

A Boyle's Law Demonstrator.  

ERIC Educational Resources Information Center

The usual apparatus for demonstrating Boyle's law produces reasonably accurate results, but is not impressive as a demonstration because students cannot easily appreciate the change in pressure. An apparatus designed to produce a more effective demonstration is described. Procedures employed are also described. (JN)

Sathe, Dileep V.

1984-01-01

183

Overhead Projector Demonstrations.  

ERIC Educational Resources Information Center

Described are three chemistry demonstrations designed to be used with overhead projectors. One activity suggests an activity for determining unknown liquids. The second activity describes a plastic spot plate for overhead demonstrations. Also described is a demonstration to show pH of selected chemicals. (RH)

Kolb, Doris, Ed.

1987-01-01

184

Demonstration Experiments in Physics  

ERIC Educational Resources Information Center

This book represents a "cookbook" for teachers of physics, a book of recipes for the preparation of demonstration experiments to illustrate the principles that make the subject of physics so fascinating. Illustrations and explanations of each demonstration are done in an easy-to-understand format. Each can be adapted to be used as a demonstration

Sutton, Richard M.

2003-01-01

185

Status of MICE  

NASA Astrophysics Data System (ADS)

The Muon Ionization Cooling Experiment (MICE) is an experiment currently under construction at the Rutherford Appleton Laboratory (RAL) in the UK. The aim of the experiment is to demonstrate the concept of ionization cooling for a beam of muons, crucial for the requirements of a Neutrino Factory and a Muon Collider. Muon cooling is achieved by measuring the reduction of the four dimensional transverse emittance for a beam of muons passing through low density absorbers and then accelerating the longitudinal component of the momentum using RF cavities. The absorbers are maintained in a focusing magnetic field to reduce the beta function of the beam and the RF cavities are kept inside coupling coils. The main goal of MICE is to measure a fractional drop in emittance, of order -10% for large emittance beams, with an accuracy of 1% (which imposes a requirement that the absolute emittance be measured with an accuracy of 0.1%). This paper will discuss the status of MICE, including the progress in commissioning the muon beam line at the ISIS accelerator at RAL, the construction of the different detector elements in MICE and the prospects for the future.

Soler, F. J. P.

2010-03-01

186

Status of MICE  

SciTech Connect

The Muon Ionization Cooling Experiment (MICE) is an experiment currently under construction at the Rutherford Appleton Laboratory (RAL) in the UK. The aim of the experiment is to demonstrate the concept of ionization cooling for a beam of muons, crucial for the requirements of a Neutrino Factory and a Muon Collider. Muon cooling is achieved by measuring the reduction of the four dimensional transverse emittance for a beam of muons passing through low density absorbers and then accelerating the longitudinal component of the momentum using RF cavities. The absorbers are maintained in a focusing magnetic field to reduce the beta function of the beam and the RF cavities are kept inside coupling coils. The main goal of MICE is to measure a fractional drop in emittance, of order -10% for large emittance beams, with an accuracy of 1%(which imposes a requirement that the absolute emittance be measured with an accuracy of 0.1%). This paper will discuss the status of MICE, including the progress in commissioning the muon beam line at the ISIS accelerator at RAL, the construction of the different detector elements in MICE and the prospects for the future.

Soler, F. J. P. [University of Glasgow, Glasgow G12 8QQ (United Kingdom)

2010-03-30

187

Feature Subset Selection Using a Genetic Algorithm  

Microsoft Academic Search

Practical pattern classification and knowledge discovery problems require selection of a subset of attributes or features (from a much larger set) to represent the patterns to be classified. This paper presents an approach to the multi-criteria optimization problem of feature subset selection using a genetic algorithm. Our experiments demonstrate the feasibility of this approach for feature subset selection in the

Jihoon Yang; Vasant Honavar

1998-01-01

188

Data surety demonstrations  

SciTech Connect

The use of data surety within the International Monitoring System (IMS) is designed to offer increased trust of acquired sensor data at a low cost. The demonstrations discussed in the paper illustrate the feasibility of hardware authentication for sensor data and commands in a retrofit environment and a new system and of the supporting key management system. The individual demonstrations which are summarized in the paper are: (1) demonstration of hardware authentication for communication authentication in a retrofit environment; (2)demonstration of hardware authentication in a new system; and (3) demonstration of key management for sensor data and command authentication.

Draelos, T.; Harris, M.; Herrington, P.; Kromer, D.

1998-08-01

189

METCAN demonstration manual, version 1.0  

NASA Technical Reports Server (NTRS)

The various features of the Metal Matrix Composite Analyzer (METCAN) computer program to simulate the high temperature nonlinear behavior of continuous fiber reinforced metal matrix composites are demonstrated. Different problems are used to demonstrate various capabilities of METCAN for both static and cyclic analyses. A complete description of the METCAN output file is also included to help interpret results.

Lee, H.-J.; Murthy, P. L. N.

1992-01-01

190

Modulation of arachidonic and linoleic acid metabolites in myeloperoxidase deficient mice during acute inflammation  

PubMed Central

Acute inflammation is a common feature of many life-threatening pathologies, including septic shock. One hallmark of acute inflammation is the peroxidation of polyunsaturated fatty acids forming bioactive products, which regulate inflammation. Myeloperoxidase (MPO) is an abundant phagocyte-derived hemoprotein released during phagocyte activation. Here, we investigated the role of MPO in modulating biologically active arachidonic acid (AA) and linoleic acid (LA) metabolites during acute inflammation. Wild-type and MPO-knockout (KO) mice were exposed to intraperitoneally injected endotoxin for 24 h, and plasma LA and AA oxidation products were comprehensively analyzed using a liquid chromatography-mass spectrometry method. Compared to wild-type mice, MPO-KO mice had significantly lower plasma levels of LA epoxides and corresponding LA- and AA-derived fatty acid diols. AA and LA hydroxy intermediates (hydroxyeicosatetraenoic and hydroxyoctadecadienoic acids) were also significantly lower in MPO-KO mice. Conversely, MPO-deficient mice had significantly higher plasma levels of cysteinyl-leukotrienes with well-known pro-inflammatory properties. In vitro experiments revealed significantly lower amounts of AA and LA epoxides, LA- and AA-derived fatty acid diols, and AA and LA hydroxy intermediates in stimulated polymorphonuclear neutrophils isolated from MPO-KO mice. Our results demonstrate that MPO modulates the balance of pro- and anti-inflammatory lipid mediators during acute inflammation. In this way, may control acute inflammatory diseases.

Kubala, Lukas; Schmelzer, Kara R.; Klinke, Anna; Kolarova, Hana; Baldus, Stephan; Hammock, Bruce D.; Eiserich, Jason P.

2010-01-01

191

Auf1/Hnrnpd-Deficient Mice Develop Pruritic Inflammatory Skin Disease  

PubMed Central

Mice lacking heterogenous nuclear ribonuclear protein D (Hnrnpd), also known as Auf1, a regulator of inflammatory cytokine mRNA stability, develop chronic dermatitis with age that is characterized by pruritis and excoriations. Histological analysis showed marked epidermal acanthosis and spongiosis, neovascularization, and elevated number of inflammatory cells, including T cells, macrophages, neutrophils, mast cells, and eosinophils. Hnrnpd-deficient (Hnrnpdtm1Rjsc) mice with dermatitis display elevated serum IgE levels. Lesions in Hnrnpdtm1Rjsc mice were associated with a shift towards a Th2 immune environment. Evaluation of T-cell-mediated skin inflammation by assaying contact hypersensitivity indicated an increased response in Hnrnpdtm1Rjsc mice. T cells and macrophages from Hnrnpdtm1Rjsc mice demonstrate a number of abnormalities associated with dermatitis, including increased IL2, tumor-necrosis factor-? (TNF?), and IL1? production. Finally, many features of spontaneous dermatitis could be recapitulated in experimentally induced lesions by subcutaneous injection of CCL27 and TNF in unaffected Hnrnpdtm1Rjsc mice. Collectively, these data highlight the importance of HNRNPD and proper regulation of mRNA stability in the intricate processes of leukocyte recruitment and inflammatory activation within the skin.

Sadri, Navid; Schneider, Robert J.

2014-01-01

192

The Microgravity Demonstrator  

NASA Technical Reports Server (NTRS)

The Demonstrator is a tool to create microgravity conditions in your classroom. A series of demonstrations is used to provide a dramatically visual, physical connection between free-fall and microgravity conditions and to understand why various types of experiments are performed under microgravity conditions. A wealth of back-round material on free-fall, microgravity, and micro-gravity sciences is available in two educational documents available through the NASA Teacher Resource Centers: Microgravity-Activity Guide for Science, Mathematics, and Technology Education, and The Mathematics of Microgravity. The remainder of this manual is divided into five sections. The first explains how to put the Microgravity Demonstrator together. The next section introduces the individual demonstrations and discusses the underlying physical science concepts. Following that are detailed steps for conducting each demonstration to make your use of the Demonstrator most effective. Next are some ideas on how to make your own Microgravity Demonstrator. The last section is a tips and troubleshooting guide for video connections and operations. If you have one of the NASA Microgravity Demonstrators, this entire manual should be useful. If you have a copy of the Microgravity Demonstrator Videotape and would like to use that as a teaching tool, the Demonstrations and Scientific Background section of this manual will give you insight into the science areas studied in microgravity.

Rogers, Melissa J. B.; Wargo, Michael J.

1999-01-01

193

Demonstrating Bacterial Flagella.  

ERIC Educational Resources Information Center

Describes an effective laboratory method for demonstrating bacterial flagella that utilizes the Proteus mirabilis organism and a special harvesting technique. Includes safety considerations for the laboratory exercise. (MDH)

Porter, John R.; And Others

1992-01-01

194

Exploration Technology Development & Demonstration  

NASA Video Gallery

Chris Moore delivers a presentation from the Exploration Technology Development & Demonstration (ETDD) study team on May 25, 2010, at the NASA Exploration Enterprise Workshop held in Galveston, TX....

195

Feature Evaluation Tools.  

National Technical Information Service (NTIS)

Measurements or transformations of measurements (i.e., features) are often used for distinguishing between items or groups of interest. For example, cepstral features are useful for speaker identification. Given a large set of possible features, the probl...

B. Costello

2002-01-01

196

[Cardiac tumors: CT and MR imaging features].  

PubMed

The CT and MR imaging features of the main cardiac tumors will be reviewed. Cross-sectional imaging features may help differentiate between cardiac tumors and pseudotumoral lesions and identify malignant features. Based on clinical features, imaging findings are helpful to further characterize the nature of the lesion. CT and MR imaging can demonstrate the relationship of the tumor with adjacent anatomical structures and are invaluable in the presurgical work-up and postsurgical follow-up. PMID:20814374

Moskovitch, G; Chabbert, V; Escourrou, G; Desloques, L; Otal, P; Glock, Y; Rousseau, H

2010-09-01

197

MICE Staging and Status  

NASA Astrophysics Data System (ADS)

Ionization cooling will be a key technique for a high-intensity Neutrino Factory or Muon Collider. The Muon Ionization Cooling Experiment (MICE) is a high-precision, staged accelerator experiment being performed at Rutherford Appleton Laboratory in the UK. Its goal is the first demonstration, with 0.1% resolution, of the feasibility of reducing the transverse emittance of a beam of muons by ionization cooling in low-Z absorbers. MICE is being staged in the following steps: I. Creating and characterizing a beam of muons; II. Measuring their emittance; III. Systematic comparison of successive measurements; IV. Inserting absorber; V. Reaccelerating longitudinally; and VI. Complete ``10%-cooling'' test. Step I is currently in progress with Step II to commence next year; completion of Step VI is anticipated in ~2012.

Hanlet, Pierrick

2010-03-01

198

Parkinsonian features after streptococcal pharyngitis.  

PubMed

Bradykinesia and rigidity developed in a 10-year-old girl during an episode of Sydenham chorea. These parkinsonian features improved over 6 months. Serum analysis demonstrated elevated anti-streptolysin-O and anti-basal ganglia antibodies. We suggest that autoimmune antibodies may cause remitting parkinsonian signs subsequent to streptococcal tonsillitis as part of the spectrum of poststreptococcal CNS disease. PMID:12970645

Ben-Pazi, Hilla; Livne, Amir; Shapira, Yehuda; Dale, Russell C

2003-08-01

199

Tested Demonstrations: Spectroscopy Illustrated.  

ERIC Educational Resources Information Center

Background information and procedures are provided for an experiment to prepare three metal derivatives of dimethyl sulfoxide (DMSO) and to determine some structural features of these derivatives based on their infrared spectra. Results and discussion of reactions involved are also provided. (JN)

Gilbert, George L., Ed.

1983-01-01

200

A Greener Chemiluminescence Demonstration  

ERIC Educational Resources Information Center

Because they are dramatic and intriguing, chemiluminescence demonstrations have been used for decades to stimulate interest in chemistry. One of the most intense chemiluminescent reactions is the oxidation of diaryl oxalate diesters with hydrogen peroxide in the presence of a fluorescer. In typical lecture demonstrations, the commercially…

Jilani, Osman; Donahue, Trisha M.; Mitchell, Miguel O.

2011-01-01

201

Kinetics and Catalysis Demonstrations.  

ERIC Educational Resources Information Center

Eleven videotaped kinetics and catalysis demonstrations are described. Demonstrations include the clock reaction, oscillating reaction, hydrogen oxidation in air, hydrogen-oxygen explosion, acid-base properties of solids, high- and low-temperature zeolite reactivity, copper catalysis of ammonia oxidation and sodium peroxide decomposition, ammonia…

Falconer, John L.; Britten, Jerald A.

1984-01-01

202

TRUEX hot demonstration  

Microsoft Academic Search

In FY 1987, a program was initiated to demonstrate technology for recovering transuranic (TRU) elements from defense wastes. This hot demonstration was to be carried out with solution from the dissolution of irradiated fuels. This recovery would be accomplished with both PUREX and TRUEX solvent extraction processes. Work planned for this program included preparation of a shielded-cell facility for the

D. B. Chamberlain; R. A. Leonard; J. C. Hoh; E. C. Gay; D. G. Kalina; G. F. Vandegrift

1990-01-01

203

Thermohaline Circulation Demonstration  

NSDL National Science Digital Library

This activity helps the students to visualize the effects of temperature and salinity on water density, and the resulting thermohaline circulation. Important processes visualized in this demonstration are upwelling, downwelling, and the formation of haloclines, thermoclines and pycnoclines. In addition, mixing by advection is clearly demonstrated.

Venn, Cynthia

204

Token Ring Demonstration  

NSDL National Science Digital Library

This applet demonstrates a Token Ring. Users may add or delete stations (or computers) from the ring. The applet allows the user to show data being circulated around the ring. Users may also select to demonstrate the cases when one of the stations is switched off, or monitoring. (UNC E-Learning Grant)

2007-01-23

205

Better Ira Remsen Demonstration  

ERIC Educational Resources Information Center

Many versions of the classic Ira Remsen experience involving copper and concentrated nitric acid have been used as lecture demonstrations. Remsen's original reminiscence from 150 years ago is included in the Supporting Information, and his biography can be found on the Internet. This article presents a new version that makes the demonstration more…

Dalby, David K.; Maynard, James H.; Moore, John W.

2011-01-01

206

Alaska Village Demonstration Projects.  

National Technical Information Service (NTIS)

The Alaska Village Demonstration Projects (AVDP) were authorized by Section 113, P.L. 92-500 (86 STAT 816), for the purpose of demonstrating methods to improve sanitary conditions in native villages of Alaska. Central community facilities have been constr...

1973-01-01

207

Angular momentum conservation demonstration  

NSDL National Science Digital Library

A short article describing the fabrication and operation of a simple angular momentum conservation demonstration. The demonstration is based on a Lazy Susan, and cylindrical brass weights tied with a nylon string. The string can be pulled or released changing the radius or rotation of the weights.

Berg, Richard E.; Anders, Robert E.

2010-12-23

208

Newton's Laws Demonstrations  

NSDL National Science Digital Library

In this collection of demonstrations, learners explore Newton's Laws of Motion. These seventeen quick activities investigate air resistance, acceleration, terminal velocity, inertia, action-reaction, and other key concepts related to forces and motion. These demonstrations can be coupled together or conducted individually.

Rathjen, Don

2007-01-01

209

Levitation Kits Demonstrate Superconductivity.  

ERIC Educational Resources Information Center

Describes the "Project 1-2-3" levitation kit used to demonstrate superconductivity. Summarizes the materials included in the kit. Discusses the effect demonstrated and gives details on how to obtain kits. Gives an overview of the documentation that is included. (CW)

Worthy, Ward

1987-01-01

210

Diverging neural pathways assemble a behavioural state from separable features in anxiety.  

PubMed

Behavioural states in mammals, such as the anxious state, are characterized by several features that are coordinately regulated by diverse nervous system outputs, ranging from behavioural choice patterns to changes in physiology (in anxiety, exemplified respectively by risk-avoidance and respiratory rate alterations). Here we investigate if and how defined neural projections arising from a single coordinating brain region in mice could mediate diverse features of anxiety. Integrating behavioural assays, in vivo and in vitro electrophysiology, respiratory physiology and optogenetics, we identify a surprising new role for the bed nucleus of the stria terminalis (BNST) in the coordinated modulation of diverse anxiety features. First, two BNST subregions were unexpectedly found to exert opposite effects on the anxious state: oval BNST activity promoted several independent anxious state features, whereas anterodorsal BNST-associated activity exerted anxiolytic influence for the same features. Notably, we found that three distinct anterodorsal BNST efferent projections-to the lateral hypothalamus, parabrachial nucleus and ventral tegmental area-each implemented an independent feature of anxiolysis: reduced risk-avoidance, reduced respiratory rate, and increased positive valence, respectively. Furthermore, selective inhibition of corresponding circuit elements in freely moving mice showed opposing behavioural effects compared with excitation, and in vivo recordings during free behaviour showed native spiking patterns in anterodorsal BNST neurons that differentiated safe and anxiogenic environments. These results demonstrate that distinct BNST subregions exert opposite effects in modulating anxiety, establish separable anxiolytic roles for different anterodorsal BNST projections, and illustrate circuit mechanisms underlying selection of features for the assembly of the anxious state. PMID:23515158

Kim, Sung-Yon; Adhikari, Avishek; Lee, Soo Yeun; Marshel, James H; Kim, Christina K; Mallory, Caitlin S; Lo, Maisie; Pak, Sally; Mattis, Joanna; Lim, Byung Kook; Malenka, Robert C; Warden, Melissa R; Neve, Rachael; Tye, Kay M; Deisseroth, Karl

2013-04-11

211

Functional analysis of LH? knockout mice  

Microsoft Academic Search

LH and FSH act on gonadal cells to regulate steroidogenesis and gametogenesis. To model human reproductive disorders involving loss of LH function and to define LH-responsive genes, we produced knockout mice lacking the hormone-specific LH? subunit. LH? null mice are viable but demonstrate postnatal defects in gonadal growth and function resulting in infertility. Mutant males have decreased testes size, a

T. Rajendra Kumar

2007-01-01

212

Favorite Demonstration: Biological Membranes  

NSDL National Science Digital Library

This demonstration provides an excellent example of how eukaryotic cells are compartmentalized and how important the bilipid layer of the endomembrane system is in providing this sectioned architecture. This demonstration also effectively depicts how lipid barriers exhibit a hydrophobic response to polar substances such as the cytoplasm and the nucleoplasm. By disrupting the various membranes during the demonstration, students can observe the amphipathetic nature of the membranes. Although this is not a true lipid bilayer, the characteristics of the lipid fluidity in membranes is clearly exemplified.

Ellis, Gilbert

2009-01-01

213

Olfactory discrimination largely persists in mice with defects in odorant receptor expression and axon guidance  

PubMed Central

Background The defining feature of the main olfactory system in mice is that each olfactory sensory neuron expresses only one of more than a thousand different odorant receptor genes. Axons expressing the same odorant receptor converge onto a small number of targets in the olfactory bulb such that each glomerulus is made up of axon terminals expressing just one odorant receptor. It is thought that this precision in axon targeting is required to maintain highly refined odor discrimination. We previously showed that ?3GnT2?/? mice have severe developmental and axon guidance defects. The phenotype of these mice is similar to adenylyl cyclase 3 (AC3) knockout mice largely due to the significant down-regulation of AC3 activity in ?3GnT2?/? neurons. Results Microarray analysis reveals that nearly one quarter of all odorant receptor genes are down regulated in ?3GnT2?/? mice compared to controls. Analysis of OR expression by quantitative PCR and in situ hybridization demonstrates that the number of neurons expressing some odorant receptors, such as mOR256-17, is increased by nearly 60% whereas for others such as mOR28 the number of neurons is decreased by more than 75% in ?3GnT2?/? olfactory epithelia. Analysis of axon trajectories confirms that many axons track to inappropriate targets in ?3GnT2?/? mice, and some glomeruli are populated by axons expressing more than one odorant receptor. Results show that mutant mice perform nearly as well as control mice in an odor discrimination task. In addition, in situ hybridization studies indicate that the expression of several activity dependent genes is unaffected in ?3GnT2?/? olfactory neurons. Conclusions Results presented here show that many odorant receptors are under-expressed in ?3GnT2?/? mice and further demonstrate that additional axon subsets grow into inappropriate targets or minimally innervate glomeruli in the olfactory bulb. Odor evoked gene expression is unchanged and ?3GnT2?/? mice exhibit a relatively small deficit in their ability to discriminate divergent odors. Results suggest that despite the fact that ?3GnT2?/? mice have decreased AC3 activity, decreased expression of many ORs, and display many axon growth and guidance errors, odor-evoked activity in cilia of mutant olfactory neurons remains largely intact.

2012-01-01

214

Good features to track  

Microsoft Academic Search

No feature-based vision system can work until good features can be identified and tracked from frame to frame. Although tracking itself is by and large a solved problem, selecting features that can be tracked well and correspond to physical points in the world is still an open problem. We propose a feature selection criterion that is optimal by construction because

Jianbo Shi; C. Toamsi

1994-01-01

215

Methanol Cannon Demonstrations Revisited.  

ERIC Educational Resources Information Center

Describes two variations on the traditional methanol cannon demonstration. The first variation is a chain reaction using real metal chains. The second example involves using easily available components to produce sequential explosions that can be musical in nature. (AIM)

Dolson, David A.; And Others

1995-01-01

216

Distance Learning Environment Demonstration.  

National Technical Information Service (NTIS)

The Distance Learning Environment Demonstration (DLED) was a comparative study of distributed multimedia computer-based training using low cost high performance technologies. An all Pentium PC network ported to Novell/Ethernet and ATM/SONET (Asynchronous ...

C. Viren

1996-01-01

217

Overhead Projector Demonstrations.  

ERIC Educational Resources Information Center

Presented is a method of demonstrating the optical activity of glucose using an overhead projector and easily obtainable materials. Explores the difference between reflected and transmitted light (Tyndall Effect) using sodium thiosulfate, hydrochloric acid, and an overhead projector. (ML)

Hambly, Gordon F.; Goldsmith, Robert H.

1988-01-01

218

Copper Extraction Demonstration  

NSDL National Science Digital Library

Summary This demonstration uses sulfuric acid and crushed copper ore (malachite) to produce a solution of copper sulfate and carbonic acid in a beaker. When a freshly sanded nail is dropped into the copper sulfate ...

219

Thermal Conductivity Demonstrations  

NSDL National Science Digital Library

Summary Here are three ideas for demonstrating thermal conductivity to your students. I. Heat flow down a metal rod (or rods) is timed by seeing wax melt at different locations along the rod. II. A rod made of ...

220

Alaska Village Demonstration Projects.  

National Technical Information Service (NTIS)

Two demonstration projects were built as authorized by Section 113 of PL 92-500. Modular construction was used to provide central utility systems which included water supply, laundry, bathing, saunas, and wastewater treatment. Service to homes was by vehi...

B. H. Reid

1980-01-01

221

Flagship Technology Demonstrations (FTD)  

NASA Video Gallery

Mike Conley delivers a presentation from the Flagship Technology Demonstrations (FTD) study team on May 25, 2010, at the NASA Exploration Enterprise Workshop held in Galveston, TX. The purpose of t...

222

Classroom Demonstration of Sunspots.  

ERIC Educational Resources Information Center

An overhead projector, projection screen, and clear tungsten Filament light bulb operated through a dimmer or variac switch are used to demonstrate the fact that black appearance of sunspots is due only to contrast and that sunspots are bright. (SK)

Callaway, Thomas O.; And Others

1982-01-01

223

Spacecraft servicing demonstration plan  

NASA Technical Reports Server (NTRS)

A preliminary spacecraft servicing demonstration plan is prepared which leads to a fully verified operational on-orbit servicing system based on the module exchange, refueling, and resupply technologies. The resulting system can be applied at the space station, in low Earth orbit with an orbital maneuvering vehicle (OMV), or be carried with an OMV to geosynchronous orbit by an orbital transfer vehicle. The three phase plan includes ground demonstrations, cargo bay demonstrations, and free flight verifications. The plan emphasizes the exchange of multimission modular spacecraft (MMS) modules which involves space repairable satellites. Three servicer mechanism configurations are the engineering test unit, a protoflight quality unit, and two fully operational units that have been qualified and documented for use in free flight verification activity. The plan balances costs and risks by overlapping study phases, utilizing existing equipment for ground demonstrations, maximizing use of existing MMS equipment, and rental of a spacecraft bus.

Bergonz, F. H.; Bulboaca, M. A.; Derocher, W. L., Jr.

1984-01-01

224

Water Contamination Demonstration  

NSDL National Science Digital Library

Summary: Misplaced Matter and Water Pollution The drinking water pollution demonstration provides a very simple but dramatic way to get students to think about water contamination and drinking water standards, ...

225

Favorite Demonstration: Differential Weathering  

NSDL National Science Digital Library

In this inquiry-based demonstration, the consumption of a Baby Ruth candy bar is used to nurture students' interest in chemical and physical weathering. In addition, two other concepts can be illustrated: the difference between weathering and erosion and

Francek, Mark

2002-10-01

226

EPSDT Demonstration Projects.  

National Technical Information Service (NTIS)

An interim evaluation is presented of four Early and Periodic Screening, Diagnosis, and Treatment (EPSDT) demonstration projects in San Antonio, Texas; Contra Costa County, California; Cuba, New Mexico; and Washington, D.C. The Contra Costa project is exp...

H. D. Dickson

1976-01-01

227

Remote Agent Demonstration  

NASA Technical Reports Server (NTRS)

We describe the computer demonstration of the Remote Agent Experiment (RAX). The Remote Agent is a high-level, model-based, autonomous control agent being validated on the NASA Deep Space 1 spacecraft.

Dorais, Gregory A.; Kurien, James; Rajan, Kanna

1999-01-01

228

Floating Magnet Demonstration.  

ERIC Educational Resources Information Center

A room-temperature demonstration of a floating magnet using a high-temperature superconductor is described. The setup and operation of the apparatus are described. The technical details of the effect are discussed. (CW)

Wake, Masayoshi

1990-01-01

229

Projectile Demonstration 2  

NSDL National Science Digital Library

For this demonstration, the launch speed has been selected so that the projectile will hit the target. Type a new value of gravitational field in the associated field. Gun altitude may also be changed.

Christian, Wolfgang; Belloni, Mario

2008-02-19

230

Demonstration of Surface Tension.  

ERIC Educational Resources Information Center

Surface tension is a fundamental obstacle in the spontaneous formation of bubbles, droplets, and crystal nuclei in liquids. Describes a simple overhead projector demonstration that illustrates the power of surface tension that can prevent so many industrial processes. (ASK)

Rosenthal, Andrew J.

2001-01-01

231

Witches' Potion Demonstration  

NSDL National Science Digital Library

In this chemistry demonstration, learners will discover that phenolphthalein is an acid/base indicator. One learner will read a poem about four witches making a potion. Four learners will act out the parts, adding chemicals and water to different beakers (with adult supervision). Learners will enjoy the poem as the indicators react with the substances and change color. This is a fun chemistry demonstration to use during Halloween.

House, The S.

2014-01-28

232

Wind profiler demonstration system  

NASA Technical Reports Server (NTRS)

The National Oceanic and Atmospheric Administration (NOAA) has started procurement of a 30-station demonstration network of Doppler radar wind profilers to be deployed in the central United States by 1989. The purposes of this demonstration network are: (1) to assess the impact of a large wind profiler network on meteorological forecasting; (2) to test wind profiler hardware designed specifically for commercial production and widespread deployment; and (3) to provide wind data for research programs involving weather phenomena in the central United States.

Chadwick, R. B.

1986-01-01

233

Pictorial Demonstrations of Photosynthesis  

Microsoft Academic Search

Theodor Engelmann's experiments in 1882 provided the first recorded visual demonstration of light wavelengths that are absorbed\\u000a by photosynthetic pigments. Later, starch images in intact leaves were used to demonstrate photosynthesis in green plants.\\u000a Similarly, light-induced chloroplast movements can form images in leaves as a result of changes in light transmittance through\\u000a leaves and photoinhibition can form images that can

Roger P. Hangarter; Howard Gest

2004-01-01

234

Mice overexpressing BAFF develop a commensal flora-dependent, IgA-associated nephropathy  

PubMed Central

B cell activation factor of the TNF family (BAFF) is a potent B cell survival factor. BAFF overexpressing transgenic mice (BAFF-Tg mice) exhibit features of autoimmune disease, including B cell hyperplasia and hypergammaglobulinemia, and develop fatal nephritis with age. However, basal serum IgA levels are also elevated, suggesting that the pathology in these mice may be more complex than initially appreciated. Consistent with this, we demonstrate here that BAFF-Tg mice have mesangial deposits of IgA along with high circulating levels of polymeric IgA that is aberrantly glycosylated. Renal disease in BAFF-Tg mice was associated with IgA, because serum IgA was highly elevated in nephritic mice and BAFF-Tg mice with genetic deletion of IgA exhibited less renal pathology. The presence of commensal flora was essential for the elevated serum IgA phenotype, and, unexpectedly, commensal bacteria–reactive IgA antibodies were found in the blood. These data illustrate how excess B cell survival signaling perturbs the normal balance with the microbiota, leading to a breach in the normal mucosal-peripheral compartmentalization. Such breaches may predispose the nonmucosal system to certain immune diseases. Indeed, we found that a subset of patients with IgA nephropathy had elevated serum levels of a proliferation inducing ligand (APRIL), a cytokine related to BAFF. These parallels between BAFF-Tg mice and human IgA nephropathy may provide a new framework to explore connections between mucosal environments and renal pathology.

McCarthy, Douglas D.; Kujawa, Julie; Wilson, Cheryl; Papandile, Adrian; Poreci, Urjana; Porfilio, Elisa A.; Ward, Lesley; Lawson, Melissa A.E.; Macpherson, Andrew J.; McCoy, Kathy D.; Pei, York; Novak, Lea; Lee, Jeannette Y.; Julian, Bruce A.; Novak, Jan; Ranger, Ann; Gommerman, Jennifer L.; Browning, Jeffrey L.

2011-01-01

235

Matrix metalloproteinase-9 deficiency phenocopies features of preeclampsia and intrauterine growth restriction.  

PubMed

The pregnancy complication preeclampsia (PE), which occurs in approximately 3% to 8% of human pregnancies, is characterized by placental pathologies that can lead to significant fetal and maternal morbidity and mortality. Currently, the only known cure is delivery of the placenta. As the etiology of PE remains unknown, it is vital to find models to study this common syndrome. Here we show that matrix metalloproteinase-9 (MMP9) deficiency causes physiological and placental abnormalities in mice, which mimic features of PE. As with the severe cases of this syndrome, which commence early in gestation, MMP9-null mouse embryos exhibit deficiencies in trophoblast differentiation and invasion shortly after implantation, along with intrauterine growth restriction or embryonic death. Reciprocal embryo transfer experiments demonstrated that embryonic MMP9 is a major contributor to normal implantation, but maternal MMP9 also plays a role in embryonic trophoblast development. Pregnant MMP9-null mice bearing null embryos exhibited clinical features of PE as VEGF dysregulation and proteinuria accompanied by preexisting elevated blood pressure and kidney pathology. Thus, our data show that fetal and maternal MMP9 play a role in the development of PE and establish the MMP9-null mice as a much-needed model to study the clinical course of this syndrome. PMID:23776237

Plaks, Vicki; Rinkenberger, Julie; Dai, Joanne; Flannery, Margaret; Sund, Malin; Kanasaki, Keizo; Ni, Wei; Kalluri, Raghu; Werb, Zena

2013-07-01

236

Paroxysmal Dyskinesias in Mice  

PubMed Central

Animal models of human disease are important tools for revealing the underlying mechanisms of pathophysiology and developing therapeutic strategies. Several unique mouse calcium channel mutants have been identified with nonepileptic, episodic dyskinetic movements that are phenotypically similar to human paroxysmal dyskinesias. In this report, video demonstrations of these motor attacks are provided for two previously described mouse mutants, tottering and lethargic, as well as a new one, rocker. Semiquantitative comparisons using two different rating scales reveal differences in attack morphology, severity, and duration among the strains. These mice provide three independent models of paroxysmal dyskinesia and support for prior proposals that channelopathies may underlie the human disorders.

Shirley, Thomas L.; Rao, Lekha M.; Hess, Ellen J.; Jinnah, H. A.

2009-01-01

237

TRUEX hot demonstration  

SciTech Connect

In FY 1987, a program was initiated to demonstrate technology for recovering transuranic (TRU) elements from defense wastes. This hot demonstration was to be carried out with solution from the dissolution of irradiated fuels. This recovery would be accomplished with both PUREX and TRUEX solvent extraction processes. Work planned for this program included preparation of a shielded-cell facility for the receipt and storage of spent fuel from commercial power reactors, dissolution of this fuel, operation of a PUREX process to produce specific feeds for the TRUEX process, operation of a TRUEX process to remove residual actinide elements from PUREX process raffinates, and processing and disposal of waste and product streams. This report documents the work completed in planning and starting up this program. It is meant to serve as a guide for anyone planning similar demonstrations of TRUEX or other solvent extraction processing in a shielded-cell facility.

Chamberlain, D.B.; Leonard, R.A.; Hoh, J.C.; Gay, E.C.; Kalina, D.G.; Vandegrift, G.F.

1990-04-01

238

AOSTRA's upgrading demonstration program  

SciTech Connect

In Summary this has been a year of achievement for AOSTRA (Alberta Oil Sands Technology and Research Authority) and its partners in demonstrating a variety of upgrading technologies. This has been the culmination of over six years of work on studies, plans, proposals and negotiations. Three major demonstration tests have been undertaken. Over 3800 m/sup 3/ or 64 jumbo tank cars of Alberta feedstock has been sent across the continent and overseas. AOSTRA has provided over $16 million to fund these tests. This has significantly improved the choices of proven upgrading process technology now available for application in Alberta. The demonstration tests should provide both a data base for design and process guarantees as well as the confidence that the processes do work as advertised.

Bailey, R.T.

1987-01-01

239

The MICE Run Control System  

NASA Astrophysics Data System (ADS)

The Muon Ionization Cooling Experiment (MICE) is a demonstration experiment to prove the feasibility of cooling a beam of muons for use in a Neutrino Factory and/or Muon Collider. The MICE cooling channel is a section of a modified Study II cooling channel which will provide a 10% reduction in beam emittance. In order to ensure a reliable measurement, MICE will measure the beam emittance before and after the cooling channel at the level of 1%, or a relative measurement of 0.001. This renders MICE a precision experiment which requires strict controls and monitoring of all experimental parameters in order to control systematic errors. The MICE Controls and Monitoring system is based on EPICS and integrates with the DAQ, Data monitoring systems, and a configuration database. The new MICE Run Control has been developed to ensure proper sequencing of equipment and use of system resources to protect data quality. A description of this system, its implementation, and performance during recent muon beam data collection will be discussed.

Hanlet, Pierrick; Mice collaboration

2014-06-01

240

Solar Energy Demonstrations  

NASA Technical Reports Server (NTRS)

Solar energy furnishes all of the heating and hot water needs, plus 80 percent of the air conditioning, for the two-story Reedy Creek building. A unique feature of this installation is that the 16 semi-cylindrical solar collectors (center photo on opposite page with closeup of a single collector below it) are not mounted atop the roof as is customary, they actually are the roof. This arrangement eliminates the usual trusses, corrugated decking and insulating concrete in roof construction; that, in turn, reduces overall building costs and makes the solar installation more attractive economically. The Reedy Creek collectors were designed and manufactured by AAI Corporation of Baltimore, Maryland.

1979-01-01

241

Demonstrating marketing accountability.  

PubMed

Pressure on health care marketers to demonstrate effectiveness of their strategies and show their contribution to organizational goals is growing. A seven-tiered model based on the concepts of structure (having the right people, systems), process (doing the right things in the right way), and outcomes (results) is discussed. Examples of measures for each tier are provided and the benefits of using the model as a tool for measuring, organizing, tracking, and communicating appropriate information are provided. The model also provides a framework for helping management understand marketing's value and can serve as a vehicle for demonstrating marketing accountability. PMID:19064476

Gombeski, William R; Britt, Jason; Taylor, Jan; Riggs, Karen; Wray, Tanya; Adkins, Wanda; Springate, Suzanne

2008-01-01

242

Standing Wave Demonstration  

NSDL National Science Digital Library

This demonstration is intended to help students better understand the electromagnetic spectrum. At the end of this activity students will be able to explain that energy travels from the sun to the earth by means of electromagnetic waves, and that the shorter the wavelength, the higher the energy per photon. They will understand why shorter wavelengths of electromagnetic energy carry more energy than longer wavelengths. Students will also be able to demonstrate how wavelength is measured. The teacher's guide contains detailed background material, learning goals, alignment to national standards, grade level/time, details on materials and preparation, procedure, assessment ideas, and modifications for alternative learners.

243

Video Demonstration: Proportions  

NSDL National Science Digital Library

This video demonstration from Watch Know Learn will help students learning about proportions. The video will help students with some knowledge of proportions by showing examples of how to solve them. The definition of a proportion is included as well as examples of how to cross-multiply to solve proportion problems. The demonstration shows what a non-proportion problem looks like and how to solve it as well as a few examples of using the lowest common denominator to solve proportions. Flash player is required to view the video, and the running time for the video is 8:09.

2012-01-01

244

Teaching Chemistry through Observation--The Exploding Can Demonstration.  

ERIC Educational Resources Information Center

Describes procedures for a demonstration that features an exploding can. This demonstration prompts students to critically analyze the release of energy in an exothermic reaction, the work done in such a reaction, and the enthalpy. (DDR)

Golestaneh, Kamran

1998-01-01

245

Rate of Solution Demonstration  

NSDL National Science Digital Library

In this chemistry demonstration, learners investigate the factors that increase the rate of dissolution for a solid. Learners will compare how crushing sugar cubes, stirring and water temperature affect the rate at which the sugar dissolved. This resource guide includes extensions and notes about factors that accelerate dissolution and Henry's Law.

House, The S.

2014-01-28

246

Astronomy Demonstrations and Models.  

ERIC Educational Resources Information Center

Demonstrations in astronomy classes seem to be more necessary than in physics classes for three reasons. First, many of the events are very large scale and impossibly remote from human senses. Secondly, while physics courses use discussions of one- and two-dimensional motion, three-dimensional motion is the normal situation in astronomy; thus,…

Eckroth, Charles A.

247

Demonstrating Poisson Statistics.  

ERIC Educational Resources Information Center

Describes an apparatus that offers a very lucid demonstration of Poisson statistics as applied to electrical currents, and the manner in which such statistics account for shot noise when applied to macroscopic currents. The experiment described is intended for undergraduate physics students. (HM)

Vetterling, William T.

1980-01-01

248

A Magnetic Circuit Demonstration.  

ERIC Educational Resources Information Center

Presents a demonstration designed to illustrate Faraday's, Ampere's, and Lenz's laws and to reinforce the concepts through the analysis of a two-loop magnetic circuit. Can be made dramatic and challenging for sophisticated students but is suitable for an introductory course in electricity and magnetism. (JRH)

Vanderkooy, John; Lowe, June

1995-01-01

249

Overhead Projector Demonstrations.  

ERIC Educational Resources Information Center

Provides two demonstrations: (1) electrolyte migration of ions using colored ions which cross a strip of gelatin allowing for noticeable migration; and (2) photochemical reduction of Fe+3 by the citrate ion. Points out both reactions can be done in a Petri dish using common lab materials. (MVL)

Kolb, Doris, Ed.

1988-01-01

250

Overhead Projector Demonstrations.  

ERIC Educational Resources Information Center

Described are three chemistry demonstrations: (1) a simple qualitative technique for taste pattern recognition in structure-activity relationships; (2) a microscale study of gaseous diffusion using bleach, HCl, ammonia, and phenolphthalein; and (3) the rotation of polarized light by stereoisomers of limonene. (MVL)

Kolb, Doris, Ed.

1989-01-01

251

ALASKA VILLAGE DEMONSTRATION PROJECTS  

EPA Science Inventory

Two demonstration projects were built as authorized by Section 113 of PL 92-500. Modular construction was used to provide central utility systems which included water supply, laundry, bathing, saunas, and wastewater treatment. Service to homes was by vehicular delivery. Fire dest...

252

Demonstration Road Show  

NSDL National Science Digital Library

The Idaho State University Department of Physics conducts science demonstration shows at S. E. Idaho schools. Four different presentations are currently available; "Forces and Motion", "States of Matter", "Electricity and Magnetism", and "Sound and Waves". Information provided includes descriptions of the material and links to other resources.

Shropshire, Steven

2009-04-06

253

Demonstrating the Gas Laws.  

ERIC Educational Resources Information Center

Presents a complete computer program demonstrating the relationship between volume/pressure for Boyle's Law, volume/temperature for Charles' Law, and volume/moles of gas for Avagadro's Law. The programing reinforces students' application of gas laws and equates a simulated moving piston to theoretical values derived using the ideal gas law.…

Holko, David A.

1982-01-01

254

Space fabrication demonstration system  

NASA Technical Reports Server (NTRS)

The lower right aluminum beam cap roll forming mill was delivered and installed in the beam builder. The beam was brought to full operational status and beams of one to six bay lengths were produced to demonstrate full system capability. Although the cap flange waviness problem persists, work is progressing within cost and schedule.

1978-01-01

255

Solar heating demonstration  

Microsoft Academic Search

The demonstration involved a 4 panel solar collector mounted on the industrial arts building. A 120 gallon storage tank supplements a 66 gallon electric hot water heater which supplies hot water for 5 shop wash basins, girl's and boy's lavatories, and a pressure washer in the auto shop. The installation and educational uses of the system are described.

L. Bonicatto; C. Kozak

1980-01-01

256

Calculus Demonstrations Using MATLAB  

ERIC Educational Resources Information Center

The note discusses ways in which technology can be used in the calculus learning process. In particular, five MATLAB programs are detailed for use by instructors or students that demonstrate important concepts in introductory calculus: Newton's method, differentiation and integration. Two of the programs are animated. The programs and the…

Dunn, Peter K.; Harman, Chris

2002-01-01

257

Video Demonstration: Borescope Inspection  

NSDL National Science Digital Library

This module, produced by the Wind Technician TV project from Highland Community College, provides a video demonstration of the Everest XLG3 video probe used to inspect a wind turbine gearbox. This would be useful for students who are learning the visual inspection process and want to see how this specific technology works. Running time for the video is 2:59.

2012-10-24

258

DEMONSTRATION OF MICROFILTRATION TECHNOLOGY  

EPA Science Inventory

The U.S. Environmental Protection Agency, under the Superfund Innovative Technology Evaluation (SITE) program in cooperation with E.I. DuPont de Nemours & Company, Inc. (DuPont) and the Oberlin Filter Company (Oberlin), undertook a field demonstration project to evaluate microfil...

259

JSF Manufacturing Demonstration Program.  

National Technical Information Service (NTIS)

Acting through the Air force Research Laboratory at Wright Patterson AFB, the JSF Program Office selected a team led by Ratheon Systems company to refine and demonstrate a powerful set of lean practices and tools as part of the JSF Manufacturing Demonstra...

2000-01-01

260

Organic Lecture Demonstrations.  

ERIC Educational Resources Information Center

Provides a listing of 35 demonstrations designed to generate interest in organic chemistry and help put points across. Topics include opening lecture; molecular structure and properties; halogenation; nucleophilic substitution, alkenes and dienes, stereochemistry, spectroscopy, alcohols and phenols, aldehydes and ketones; carboxylic acids, amines,…

Silversmith, Ernest F.

1988-01-01

261

Electromagnetic Induction Demonstration  

NSDL National Science Digital Library

This simple demonstration shows the interaction between electricity and magnetism. Two coils of wire are held close to each other, but not touching. One is attached to a music source, such as a small radio or iPod, and the other is attached to an external speaker. Students can hear the music through the speaker even though there is no direct connection.

Hobbs, Marsha

262

More Diamagnetism Demonstrations  

NASA Astrophysics Data System (ADS)

Inspired by, among others, Charles Sawicki's description of an inexpensive diamagnetic levitation apparatus,1 we built two such devices for classroom use and for educational outreach at the National Institute of Standards and Technology, Boulder, Colo. With a slightly different setup, the same demonstration can be done horizontally on an overhead projector.

Conery, Chris; Goodrich, L. F.; Stauffer, T. C.

2003-02-01

263

A Biofeedback Demonstration.  

ERIC Educational Resources Information Center

Describes a demonstration for measurement of biophysical signals produced by the human body. The signals, after amplification, could provide acoustical feedback through a voltage-controlled oscillator (VCO), or they could be seen either with an oscilloscope or a high speed chart recorder. (GA)

Garrity, Michael K.

1978-01-01

264

Why Demonstrations Matter  

ERIC Educational Resources Information Center

The author remembers how exciting it was when the teacher had "stuff" on the front desk: unfamiliar objects and other things out of place in the traditional classroom. Years later, as a new teacher, the author learned the importance of building lessons around concepts and that demonstrations are an integral part of concept development in science.…

Black, Richard

2005-01-01

265

Lyst Mutation in Mice Recapitulates Iris Defects of Human Exfoliation Syndrome  

PubMed Central

Purpose Human eyes with exfoliation syndrome (XFS) exhibit a distinctive pattern of iris transillumination defects that are recapitulated in Lyst mutant mice carrying the beige allele. The purpose of this study was to determine the anatomic basis for Lyst-mediated transillumination defects, test whether Lyst mutant mice develop other features of XFS, and describe the molecular basis of the beige mutation. Methods Lyst mutant mice and strain-matched controls were compared by clinical, histologic, immunohistochemical, and molecular genetic analyses. Results Slit-lamp examination showed that Lyst mutant mice uniformly exhibit XFS-like transillumination defects. Histologic analysis showed that these defects correlate with a sawtooth morphology of the iris pigment epithelium. Lyst mutant mice also produce an exfoliative-like material and exhibit pronounced pigment dispersion. Despite these insults, Lyst mutation does not cause increased intraocular pressure or optic nerve damage in the C57BL/6J genetic background. Sequence analysis identified that the beige mutation is predicted to delete a single isoleucine from the WD40 domain of the LYST protein, suggesting that this mutation is likely to disrupt a protein-protein interaction. Conclusions Lyst mutant eyes exhibit multiple features of XFS. Recent human genetic association studies have identified changes occurring in the LOXL1 gene as an important risk factor for XFS but also indicated that other factors contributing to risk likely exist. These results demonstrated that mutation of the Lyst gene can produce ocular features of human XFS and suggested that LYST or LYST-interacting genes may contribute to XFS.

Trantow, Colleen M.; Mao, Mao; Petersen, Greg E.; Alward, Erin M.; Alward, Wallace L. M.; Fingert, John H.; Anderson, Michael G.

2009-01-01

266

A transgenic mouse model demonstrating the oncogenic role of mutations in the polycomb-group gene EZH2 in lymphomagenesis.  

PubMed

The histone methyltransferase EZH2 is frequently mutated in germinal center-derived diffuse large B-cell lymphoma and follicular lymphoma. To further characterize these EZH2 mutations in lymphomagenesis, we generated a mouse line where EZH2(Y641F) is expressed from a lymphocyte-specific promoter. Spleen cells isolated from the transgenic mice displayed a global increase in trimethylated H3K27, but the mice did not show an increased tendency to develop lymphoma. As EZH2 mutations often coincide with other mutations in lymphoma, we combined the expression of EZH2(Y641F) by crossing these transgenic mice with Eµ-Myc transgenic mice. We observed a dramatic acceleration of lymphoma development in this combination model of Myc and EZH2(Y641F). The lymphomas show histologic features of high-grade disease with a shift toward a more mature B-cell phenotype, increased cycling and gene expression, and epigenetic changes involving important pathways in B-cell regulation and function. Furthermore, they initiate disease in secondary recipients. In summary, EZH2(Y641F) can collaborate with Myc to accelerate lymphomagenesis demonstrating a cooperative role of EZH2 mutations in oncogenesis. This murine lymphoma model provides a new tool to study global changes in the epigenome caused by this frequent mutation and a promising model system for testing novel treatments. PMID:24802772

Berg, Tobias; Thoene, Silvia; Yap, Damian; Wee, Tracee; Schoeler, Nathalie; Rosten, Patty; Lim, Emilia; Bilenky, Misha; Mungall, Andrew J; Oellerich, Thomas; Lee, Sherry; Lai, Courteney K; Umlandt, Patricia; Salmi, Anisa; Chang, Harry; Yue, Lisa; Lai, David; Cheng, S-W Grace; Morin, Ryan D; Hirst, Martin; Serve, Hubert; Marra, Marco A; Morin, Gregg B; Gascoyne, Randy D; Aparicio, Samuel A; Humphries, R Keith

2014-06-19

267

Features in Continuous Parallel Coordinates.  

PubMed

Continuous Parallel Coordinates (CPC) are a contemporary visualization technique in order to combine several scalar fields, given over a common domain. They facilitate a continuous view for parallel coordinates by considering a smooth scalar field instead of a finite number of straight lines. We show that there are feature curves in CPC which appear to be the dominant structures of a CPC. We present methods to extract and classify them and demonstrate their usefulness to enhance the visualization of CPCs. In particular, we show that these feature curves are related to discontinuities in Continuous Scatterplots (CSP). We show this by exploiting a curve-curve duality between parallel and Cartesian coordinates, which is a generalization of the well-known point-line duality. Furthermore, we illustrate the theoretical considerations. Concluding, we discuss relations and aspects of the CPC's/CSP's features concerning the data analysis. PMID:22034308

Lehmann, Dirk J; Theisel, Holger

2011-12-01

268

Transgenic expression of human matrix metalloproteinase-1 attenuates pulmonary arterial hypertension in mice.  

PubMed

PAH (pulmonary arterial hypertension) is a debilitating and life-threatening disease, often affecting young people. We specifically expressed human MMP-1 (matrix metalloproteinase-1) in mouse macrophages and examined its effects in attenuating the decompensating features of MCT (monocrotaline)-induced PAH. Measurement of RV (right ventricular) pressure revealed a 2.5-fold increase after treatment with MCT, which was reduced to 1.5-fold in MMP-1 transgenic mice. There was conspicuous pulmonary inflammation with chronic infiltration of mononuclear cells after the administration of MCT, which was significantly diminished in transgenic mice. Furthermore, transgenic mice showed decreased collagen deposition compared with WT (wild-type). Staining for Mac-3 (macrophage-3) and ?-SMA (?-smooth muscle actin) revealed extensive infiltration of macrophages and medial hypertrophy of large pulmonary vessels with complete occlusion of small arteries respectively. These changes were markedly reduced in MMP-1 transgenic mice compared with WT. Western blotting for molecules involved in cell multiplication and proliferation depicted a significant decrease in the lung tissue of transgenic mice after the treatment with MCT. In conclusion, the present study demonstrated that transgenic expression of human MMP-1 decreased proliferation of smooth muscle cells and prevented excessive deposition of collagen in the pulmonary arterial tree. Our results indicate that up-regulation of MMP-1 could attenuate the debilitation of human PAH and provide an option for therapeutic intervention. PMID:21793800

George, Joseph; Sun, Jie; D'Armiento, Jeanine

2012-01-01

269

Feature-by-feature--evaluating de novo sequence assembly.  

PubMed

The whole-genome sequence assembly (WGSA) problem is among one of the most studied problems in computational biology. Despite the availability of a plethora of tools (i.e., assemblers), all claiming to have solved the WGSA problem, little has been done to systematically compare their accuracy and power. Traditional methods rely on standard metrics and read simulation: while on the one hand, metrics like N50 and number of contigs focus only on size without proportionately emphasizing the information about the correctness of the assembly, comparisons performed on simulated dataset, on the other hand, can be highly biased by the non-realistic assumptions in the underlying read generator. Recently the Feature Response Curve (FRC) method was proposed to assess the overall assembly quality and correctness: FRC transparently captures the trade-offs between contigs' quality against their sizes. Nevertheless, the relationship among the different features and their relative importance remains unknown. In particular, FRC cannot account for the correlation among the different features. We analyzed the correlation among different features in order to better describe their relationships and their importance in gauging assembly quality and correctness. In particular, using multivariate techniques like principal and independent component analysis we were able to estimate the "excess-dimensionality" of the feature space. Moreover, principal component analysis allowed us to show how poorly the acclaimed N50 metric describes the assembly quality. Applying independent component analysis we identified a subset of features that better describe the assemblers performances. We demonstrated that by focusing on a reduced set of highly informative features we can use the FRC curve to better describe and compare the performances of different assemblers. Moreover, as a by-product of our analysis, we discovered how often evaluation based on simulated data, obtained with state of the art simulators, lead to not-so-realistic results. PMID:22319599

Vezzi, Francesco; Narzisi, Giuseppe; Mishra, Bud

2012-01-01

270

Feature-by-Feature - Evaluating De Novo Sequence Assembly  

PubMed Central

The whole-genome sequence assembly (WGSA) problem is among one of the most studied problems in computational biology. Despite the availability of a plethora of tools (i.e., assemblers), all claiming to have solved the WGSA problem, little has been done to systematically compare their accuracy and power. Traditional methods rely on standard metrics and read simulation: while on the one hand, metrics like N50 and number of contigs focus only on size without proportionately emphasizing the information about the correctness of the assembly, comparisons performed on simulated dataset, on the other hand, can be highly biased by the non-realistic assumptions in the underlying read generator. Recently the Feature Response Curve (FRC) method was proposed to assess the overall assembly quality and correctness: FRC transparently captures the trade-offs between contigs' quality against their sizes. Nevertheless, the relationship among the different features and their relative importance remains unknown. In particular, FRC cannot account for the correlation among the different features. We analyzed the correlation among different features in order to better describe their relationships and their importance in gauging assembly quality and correctness. In particular, using multivariate techniques like principal and independent component analysis we were able to estimate the “excess-dimensionality” of the feature space. Moreover, principal component analysis allowed us to show how poorly the acclaimed N50 metric describes the assembly quality. Applying independent component analysis we identified a subset of features that better describe the assemblers performances. We demonstrated that by focusing on a reduced set of highly informative features we can use the FRC curve to better describe and compare the performances of different assemblers. Moreover, as a by-product of our analysis, we discovered how often evaluation based on simulated data, obtained with state of the art simulators, lead to not-so-realistic results.

Vezzi, Francesco; Narzisi, Giuseppe; Mishra, Bud

2012-01-01

271

LIMB Demonstration Project Extension  

SciTech Connect

The basic goal of the Limestone Injection Multistage Burner (LIMB) demonstration is to extend LIMB technology development to a full- scale application on a representative wall-fired utility boiler. The successful retrofit of LIMB to an existing boiler is expected to demonstrate that (a) reductions of 50 percent or greater in SO{sub x} and NO{sub x} emissions can be achieved at a fraction of the cost of add-on FGD systems, (b) boiler reliability, operability, and steam production can be maintained at levels existing prior to LIMB retrofit, and (c) technical difficulties attributable to LIMB operation, such as additional slagging and fouling, changes in ash disposal requirements, and an increased particulate load, can be resolved in a cost-effective manner. The primary fuel to be used will be an Ohio bituminous coal having a nominal sulfur content of 3 percent or greater.

Not Available

1989-06-15

272

Chemical Domino Demonstration  

NASA Astrophysics Data System (ADS)

The Chemical Domino Demonstration is both educational and entertaining. It provides an excellent means for a review of chemical concepts at the conclusion of a general chemistry course. This demonstration consists of a number of different chemical reactions occurring in sequence in a Rube Goldberg-type apparatus. These reactions include the reduction of water by an active metal, the oxidation of a moderately active metal by an acid, reduction of metallic ions by a metal of greater activity, acid-base neutralization reactions in solution monitored with indicators, a gas-phase acid-base neutralization reaction, decomposition of a compound, precipitation of an insoluble salt, substitution reactions of coordination complexes, and pyrotechnic oxidation-reduction reactions including a hypergolic oxidation-reduction reaction, an intramolecular oxidation-reduction reaction, and the combustion of a flammable gas.

Alexander, M. Dale

1998-04-01

273

Molecular Dynamics Demonstration Model  

NSDL National Science Digital Library

The EJS Molecular Dynamics Demonstration model is constructed using the Lennard-Jones potential truncated at a distance of 3 molecular diameters. The motion of the molecules is governed by Newton's laws, approximated using the Verlet algorithm with the indicated Time step. For sufficiently small time steps dt, the system's total energy should be approximately conserved. Users can select various initial configurations using the drop down menu. Ejs Molecular Dynamics Demonstration model was created using the Easy Java Simulations (Ejs) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the js_stp_md_MolecularDynamicsDemo.jar file will run the program if Java is installed. Ejs is a part of the Open Source Physics Project and is designed to make it easier to access, modify, and generate computer models. Additional Ejs models for statistical mechanics are available. They can be found by searching ComPADRE for Open Source Physics, OSP, or Ejs.

Christian, Wolfgang

2008-11-15

274

Bioreactor Landfill Demonstration Project  

NSDL National Science Digital Library

Managed by the Florida Center for Solid and Hazardous Waste Management, this Website provides information on the Bioreactor Landfill Demonstration Project. The slow decomposition rates in current municipal landfills have prompted research in bioreactor landfills, which operate under the "wet cell" theory where moisture is added to enhance degradation. The Research section contains a plethora of material, including the Bioreactor Presentation, which consists of 60 slides outlining the project and solid waste issues, and A Proposed Bioreactor Landfill Demonstration Project, which is the proposal that started the project. The proposal is a great source of background information about bioreactor landfills. Though not all of the topics listed on the site have active links, the information available is worthwhile.

275

The MICE Particle Identification System  

NASA Astrophysics Data System (ADS)

The Muon Ionization Cooling Experiment (MICE) at the ISIS accelerator located at the Rutherford Appleton Laboratory, UK, will be the first experiment to study muon cooling at high precision. Demonstration of muon ionization cooling is a major technological step towards the construction of a neutrino factory or a muon collider. A muon beam is produced via pion decay in the MICE beam line within a range of emittances and momenta. Muon purity is assured by a system of detectors for particle identification (PID). We describe briefly the PID system here.

Bogomilov, M.; MICE Collaboration

276

Feature Writing for Newspapers.  

ERIC Educational Resources Information Center

This book is designed to teach students and professionals how to write features for newspapers. The author defines the basic elements of feature writing and explains the specialized techniques that have evolved through years of trial and error. Samples of newspaper feature articles are included, and realistic reporting situations are presented to…

Williamson, Daniel R.

277

Overhead Projector Demonstrations.  

ERIC Educational Resources Information Center

Describes two oscillating reactions: the Briggs-Raucher reaction using H202, KIO3, malonic acid, and MnSO4 which changes from yellow to blue, and the Belousov-Zhabotinskii reaction uses NaBrO3, NaBr, malonic acid, and ferroin solution and changes from red to blue. Includes a third color demonstration on the six oxidation states of manganese. (MVL)

Kolb, Doris

1988-01-01

278

Invisible Ink Demonstration  

NSDL National Science Digital Library

In this chemistry demonstration, learners will discover that phenolphthalein is a chemical that displays different colors depending on the acidity or basicity of the environment. Learners will be surprised to see a "secret message" appear in bright pink ink when it is sprayed with Windex containing ammonia (a base). They compare this to what happens when the message is sprayed with Windex containing acetic acid (nothing!).

House, The S.

2014-01-28

279

NAVAJO ELECTRIFICATION DEMONSTRATION PROJECT  

Microsoft Academic Search

The Navajo Electrification Demonstration Project (NEDP) is a multi-year project which addresses the electricity needs of the unserved and underserved Navajo Nation, the largest American Indian tribe in the United States. The program serves to cumulatively provide off-grid electricty for families living away from the electricty infrastructure, line extensions for unserved families living nearby (less than 1\\/2 mile away from)

Terry W. Battiest

2008-01-01

280

My Favorite Classroom Demonstration  

Microsoft Academic Search

This is a new kind of session for an AAS meeting: very short presentations of favorite classroom demonstrations. It is INFORMAL - no advance registation or abstracts. However, if you want to do a demo, PLEASE EMAIL aased@aas.org IN ADVANCE, telling the name of your demo and how long it takes. This is so we don't overfill the half-hour experimental

D. Duncan

1998-01-01

281

Simple SAR demonstrator  

NASA Astrophysics Data System (ADS)

In this paper we present a simple SAR radar demonstrator build using commercially available (COTS) components. For the microwave analog front end, a standard police radar microwave head has been used. The Motorola DSP processor board, equipped with ADC and DAC, has been used for generating of modulating signal and for signal acquisition. The raw radar signal (I and Q components) have been recorded on 2.5" HDD. The signal processing has been performed on standard PC computer after copying the recorded data. The aim of constructing simple and relatively cheap demonstrator was to provide the students the real-life unclassified radar signals and motivate them to test and develop various kinds of SAR and ISAR algorithms, including image formation, motion compensation and autofocusing. The simple microwave frontend hardware has a lot of non-idealities, so for obtaining nice SAR image it was necessary to develop the number of correction algorithms at the calibration stage. The SAR demonstrator have been tested using car as a moving platform. The flight tests with a small airborne platform are planned for the summer.

Kulpa, Krzysztof; Misiurewicz, Jacek; Baranowski, Piotr; Wojdo?owicz, Grzegorz

2008-01-01

282

Lunar Water Resource Demonstration  

NASA Technical Reports Server (NTRS)

In cooperation with the Canadian Space Agency, the Northern Centre for Advanced Technology, Inc., the Carnegie-Mellon University, JPL, and NEPTEC, NASA has undertaken the In-Situ Resource Utilization (ISRU) project called RESOLVE. This project is a ground demonstration of a system that would be sent to explore permanently shadowed polar lunar craters, drill into the regolith, determine what volatiles are present, and quantify them in addition to recovering oxygen by hydrogen reduction. The Lunar Prospector has determined these craters contain enhanced hydrogen concentrations averaging about 0.1%. If the hydrogen is in the form of water, the water concentration would be around 1%, which would translate into billions of tons of water on the Moon, a tremendous resource. The Lunar Water Resource Demonstration (LWRD) is a part of RESOLVE designed to capture lunar water and hydrogen and quantify them as a backup to gas chromatography analysis. This presentation will briefly review the design of LWRD and some of the results of testing the subsystem. RESOLVE is to be integrated with the Scarab rover from CMIJ and the whole system demonstrated on Mauna Kea on Hawaii in November 2008. The implications of lunar water for Mars exploration are two-fold: 1) RESOLVE and LWRD could be used in a similar fashion on Mars to locate and quantify water resources, and 2) electrolysis of lunar water could provide large amounts of liquid oxygen in LEO, leading to lower costs for travel to Mars, in addition to being very useful at lunar outposts.

Muscatello, Anthony C.

2008-01-01

283

Demonstration of Berry Phase in Optical Spectroscopy  

NASA Technical Reports Server (NTRS)

In this paper we demonstrate that the observed phase shift of the RF signal and its intensity dependence under extreme low pump and probe laser field conditions are dominated by Berry phase effect in optical spectroscopy with good adiabatic approximation, which provides all features' agreements between the theoretical and the experimental results.

Xia, Hui-Rong; Zhang, Yong; Jiang, Hong-Ji; Ding, Liang-En

1996-01-01

284

Vehicle detection fusing 2D visual features  

Microsoft Academic Search

This paper presents a method for detection and tracking of vehicles by finding various characteristic features in the images of a monochrome camera. The detection process uses shadow and symmetry features to generate vehicle hypotheses. These are fused and tracked over time using an Interacting Multiple Model method (IMM). Results for natural traffic scenes demonstrate high reliability of the proposed

C. Hoffman; Thao Dang; Christoph Stiller

2004-01-01

285

Space Research Benefits Demonstrated  

NASA Technical Reports Server (NTRS)

Angie Jackman, a NASA project manager in microgravity research, demonstrates the enhanced resilience of undercooled metal alloys as compared to conventional alloys. Experiments aboard the Space Shuttle helped scientists refine their understanding of the physical properties of certain metal alloys when undercooled (i.e., kept liquid below their normal solidification temperature). This new knowledge then allowed scientists to modify a terrestrial production method so they can now make limited quantities marketed under the Liquid Metal trademark. The exhibit was a part of the NASA outreach activity at AirVenture 2000 sponsored by the Experimental Aircraft Association in Oshkosh, WI.

2000-01-01

286

Exploration Medical System Demonstration  

NASA Technical Reports Server (NTRS)

BACKGROUND: Exploration class missions will present significant new challenges and hazards to the health of the astronauts. Regardless of the intended destination, beyond low Earth orbit a greater degree of crew autonomy will be required to diagnose medical conditions, develop treatment plans, and implement procedures due to limited communications with ground-based personnel. SCOPE: The Exploration Medical System Demonstration (EMSD) project will act as a test bed on the International Space Station (ISS) to demonstrate to crew and ground personnel that an end-to-end medical system can assist clinician and non-clinician crew members in optimizing medical care delivery and data management during an exploration mission. Challenges facing exploration mission medical care include limited resources, inability to evacuate to Earth during many mission phases, and potential rendering of medical care by non-clinicians. This system demonstrates the integration of medical devices and informatics tools for managing evidence and decision making and can be designed to assist crewmembers in nominal, non-emergent situations and in emergent situations when they may be suffering from performance decrements due to environmental, physiological or other factors. PROJECT OBJECTIVES: The objectives of the EMSD project are to: a. Reduce or eliminate the time required of an on-orbit crew and ground personnel to access, transfer, and manipulate medical data. b. Demonstrate that the on-orbit crew has the ability to access medical data/information via an intuitive and crew-friendly solution to aid in the treatment of a medical condition. c. Develop a common data management framework that can be ubiquitously used to automate repetitive data collection, management, and communications tasks for all activities pertaining to crew health and life sciences. d. Ensure crew access to medical data during periods of restricted ground communication. e. Develop a common data management framework that allows for scalability, extensibility, and interoperability of data sources and data users. f. Lower total cost of ownership for development and sustainment of peripheral hardware and software that use EMSD for data management. g. Provide a better standard of healthcare for crew members through reductions in the time required by crew and ground personnel to provide medical treatment and the number of crew errors experienced during treatment.

Rubin, D. A.; Watkins, S. D.

2014-01-01

287

Floating Pennies Demonstration  

NSDL National Science Digital Library

The Materials Science and Technology Teacher's Workshop (MAST) provides this demonstration on the different reactivities of copper and zinc to hydrochloric acid. In this module, the reactivities of copper and zinc to hydrochloric acid will be used to separate the two metals in a post-1983 penny. The percent of zinc and of copper can be calculated as well as the economic value of each. The lesson includes a step by step explanation of the laboratory procedure. Discussion questions and a video clip are also included.

2012-05-03

288

Slime: Classroom Demonstration  

NSDL National Science Digital Library

The Materials Education Resource Center has provided this hands on lab activity created by Andrew Nydam and Debbie Goodwin. The activity demonstrates property change due to crosslinking in slime formed from mixing PVA and Borax solution. This lab will teach the students the important concepts of plastic flow vs. elastic flow, hydrogen bonding, and viscosity. This pdf document provides instructions for the instructor, recommendations to ensure the experiment goes smoothly for both students and teacher, and an evaluation packet for the students to complete once the lab is finished. All in all, this is a fun and education tool for any high school or community college science classroom.

Goodwin, Debbie; Nydam, Andrew

2010-08-06

289

Demonstration of optical microfluidics  

NASA Astrophysics Data System (ADS)

We demonstrate a novel method for the control of small droplets using laser-based heating. Temperature dependent interfacial surface tensions were the primary force used to move droplets. With this approach, ~1.7 ?L to 14 pL droplets were moved on a bare, unmodified polystyrene surface, at speeds of up to 3 mm/s. Upon contact, droplets spontaneously fused and rapidly mixed within 33 ms. We performed an optical absorption-based protein assay using horseradish peroxidase and a chromogenic substrate (ABTS), and readily detected as little as ~125 attomoles of reacting enzyme.

Kotz, Kenneth T.; Kalogerakis, Konstantinos S.; Noble, Kyle A.; Smith, Sarah E.; Faris, Gregory W.

2004-06-01

290

Preventing formation of Reticulon 3 Immunoreactive Dystrophic Neurites improves cognitive function in mice  

PubMed Central

Neuritic dystrophy is one of the important pathological features associated with amyloid plaques in Alzheimer’s disease (AD) and age-dependent neuronal dysfunctions. We have previously reported that reticulon-3 (RTN3) immunoreactive dystrophic neurites (RIDNs) are abundantly present in the hippocampus of AD patients, in AD mouse models and in aged wild-type mice. Transgenic mice overexpressing the human RTN3 transgene spontaneously develop RIDNs in their hippocampi and the formation of RIDNs correlates with the appearance of RTN3 aggregation. To further elucidate whether the formation of RIDNs is reversible, we generated transgenic mice expressing wild-type human RTN3 under the control of a tetracycline-responsive promoter. Treatment with doxycycline for two months effectively turned off expression of the human RTN3 transgene, confirming the inducible nature of the system. However, the formation of hippocampal RIDNs was dependent on whether the transgene was turned off before or after the formation of RTN3 aggregates. When transgenic human RTN3 expression was turned off at young age, formation of RIDNs was largely eliminated compared to the vehicle-treated transgenic mice. More importantly, a fear conditioning study demonstrated that contextual associative learning and memory in inducible transgenic mice was improved if the density of RIDNs was lowered. Further mechanistic study suggested that a reduction in BDNF levels in transgenic mice might contribute to the reduced learning and memory in transgenic mice overexpressing RTN3. Hence, we conclude that age-dependent RIDNs cannot be effectively cleared once they have formed and we postulate that successful prevention of RIDN formation should be initiated prior to RTN3 aggregation.

Shi, Qi; Prior, Marguerite; Zhou, Xiangdong; Tang, Xiaoying; He, Wanxia; Hu, Xiangyou; Yan, Riqiang

2013-01-01

291

Vortex Apparatus and Demonstrations  

NASA Astrophysics Data System (ADS)

Vortex flow, from millimeter to kilometer in scale, is important in many scientific and technological areas.1 Examples are seen in water strider locomotion, from industrial pipe flow (wastewater treatment) to air traffic control (safe distance between aircrafts on a runway ready for takeoff) to atmospheric studies.2-5 In this paper, we focus on a particular vortex known as bathtub vortex (BTV). It occurs when water is drained from a hole at the bottom of a container such as a bathtub or a sink under the action of gravity. The vortex has a funnel shape with a central air core, resembling a tornado. We have designed a portable apparatus to demonstrate bathtub vortex on a continual basis. The apparatus consists of a clear cylinder supported by a frame over a water reservoir and a submersible pump. Young and old have been equally amazed by watching the demonstrations at various public presentations held at the University of the Pacific recently. With material cost of less than $100, the apparatus can be easily fabricated and used at other universities. With a short set-up time, it is an ideal device for promoting science to the general public, and it can be used to enhance lectures in physics courses as well.

Shakerin, Said

2010-05-01

292

SSME Key Operations Demonstration  

NASA Technical Reports Server (NTRS)

A Space Shuttle Main Engine (SSME) test program was conducted between August 1995 and May 1996 using the Technology Test Bed (TTB) Engine. SSTO vehicle studies have indicated that increases in the propulsion system operating range can save significant weight and cost at the vehicle level. This test program demonstrated the ability of the SSME to accommodate a wide variation in safe operating ranges and therefore its applicability to the SSTO mission. A total of eight tests were completed with four at Marshall Space Flight Center's Advanced Engine Test Facility and four at the Stennis Space Center (SSC) A-2 attitude test stand. Key demonstration objectives were: 1) Mainstage operation at 5.4 to 6.9 mixture ratio; 2) Nominal engine start with significantly reduced engine inlet pressures of 50 psia LOX and 38 psia fuel; and 3) Low power level operation at 17%, 22%, 27%, 40%, 45%, and 50% of Rated Power Level. Use of the highly instrumented TTB engine for this test series has afforded the opportunity to study in great detail engine system operation not possible with a standard SSME and has significantly contributed to a greater understanding of the capabilities of the SSME and liquid rocket engines in general.

Anderson, Brian; Bradley, Michael; Ives, Janet

1997-01-01

293

PFBC Utility Demonstration Project  

SciTech Connect

This report provides a summary of activities by American Electric Power Service Corporation during the first budget period of the PFBC Utility Demonstration Project. In April 1990, AEP signed a Cooperative Agreement with the US Department of Energy to repower the Philip Sporn Plant, Units 3 4 in New Haven, West Virginia, with a 330 KW PFBC plant. The purpose of the program was to demonstrate and verify PFBC in a full-scale commercial plant. The technical and cost baselines of the Cooperative Agreement were based on a preliminary engineering and design and a cost estimate developed by AEP subsequent to AEP's proposal submittal in May 1988, and prior to the signing of the Cooperative Agreement. The Statement of Work in the first budget period of the Cooperative Agreement included a task to develop a preliminary design and cost estimate for erecting a Greenfield plant and to conduct a comparison with the repowering option. The comparative assessment of the options concluded that erecting a Greenfield plant rather than repowering the existing Sporn Plant could be the technically and economically superior alternative. The Greenfield plant would have a capacity of 340 MW. The ten additional MW output is due to the ability to better match the steam cycle to the PFBC system with a new balance of plant design. In addition to this study, the conceptual design of the Sporn Repowering led to several items which warranted optimization studies with the goal to develop a more cost effective design.

Not Available

1992-11-01

294

Generation of T Cell Responses Targeting the Reactive Metabolite of Halothane in Mice  

PubMed Central

Immune-mediated adverse drug reactions (IADRs) represent a significant problem in clinical practice and drug development. Studies of the underlying mechanisms of IADRs have been hampered by the lack of animal models. Halothane causes severe allergic hepatitis with clinical features consistent with an IADR. Our ultimate goal is to develop a mouse model of halothane hepatitis. Evidence suggests that adaptive immune responses targeting liver protein adducts of the reactive metabolite (TFA) play an important role in the pathogenesis. The present study demonstrated that the combination of an anti-CD40 antibody and a Toll-like receptor (TLR) agonist served as a potent adjuvant in generating TFA-specific T cell responses in mice. Both CD4+ and CD8+ subsets of T cells were activated and the TFA-specific responses were detected not only in the spleen but also in the liver of mice immunized with mouse serum albumin adducts of TFA (TFA-MSA) plus the combined CD40/TLR agonist. Whereas all three TLR agonists examined were effective in eliciting TFA-specific immune responses in BALB/cByJ mice, only polyI:C was effective in DBA/1 mice and none of the TLR agonists could aid the generation of TFA-specific T cells in C57BL/6J mice. This result, combined with our previous finding that BALB/cByJ mice were the most susceptible to halothane-induced acute liver injury, provides the basis for employing this strain in future studies. Collectively, our data demonstrated the successful completion of a crucial first step in the development of a murine model of halothane hepatitis.

You, Qiang; Cheng, Linling; Ju, Cynthia

2010-01-01

295

Fuel Cell Demonstration Program  

SciTech Connect

In an effort to promote clean energy projects and aid in the commercialization of new fuel cell technologies the Long Island Power Authority (LIPA) initiated a Fuel Cell Demonstration Program in 1999 with six month deployments of Proton Exchange Membrane (PEM) non-commercial Beta model systems at partnering sites throughout Long Island. These projects facilitated significant developments in the technology, providing operating experience that allowed the manufacturer to produce fuel cells that were half the size of the Beta units and suitable for outdoor installations. In 2001, LIPA embarked on a large-scale effort to identify and develop measures that could improve the reliability and performance of future fuel cell technologies for electric utility applications and the concept to establish a fuel cell farm (Farm) of 75 units was developed. By the end of October of 2001, 75 Lorax 2.0 fuel cells had been installed at the West Babylon substation on Long Island, making it the first fuel cell demonstration of its kind and size anywhere in the world at the time. Designed to help LIPA study the feasibility of using fuel cells to operate in parallel with LIPA's electric grid system, the Farm operated 120 fuel cells over its lifetime of over 3 years including 3 generations of Plug Power fuel cells (Lorax 2.0, Lorax 3.0, Lorax 4.5). Of these 120 fuel cells, 20 Lorax 3.0 units operated under this Award from June 2002 to September 2004. In parallel with the operation of the Farm, LIPA recruited government and commercial/industrial customers to demonstrate fuel cells as on-site distributed generation. From December 2002 to February 2005, 17 fuel cells were tested and monitored at various customer sites throughout Long Island. The 37 fuel cells operated under this Award produced a total of 712,635 kWh. As fuel cell technology became more mature, performance improvements included a 1% increase in system efficiency. Including equipment, design, fuel, maintenance, installation, and decommissioning the total project budget was approximately $3.7 million.

Gerald Brun

2006-09-15

296

Electrodynamic Dust Shield Demonstrator  

NASA Technical Reports Server (NTRS)

The objective of the project was to design and manufacture a device to demonstrate a new technology developed by NASA's Electrostatics and Surface Physics Laboratory. The technology itself is a system which uses magnetic principles to remove regolith dust from its surface. This project was to create an enclosure that will be used to demonstrate the effectiveness of the invention to The Office of the Chief Technologist. ONE of the most important challenges of space exploration is actually caused by something very small and seemingly insignificant. Dust in space, most notably on the moon and Mars, has caused many unforeseen issues. Dirt and dust on Earth, while a nuisance, can be easily cleaned and kept at bay. However, there is considerably less weathering and erosion in space. As a result, the microscopic particles are extremely rough and abrasive. They are also electrostatically charged, so they cling to everything they make contact with. This was first noted to be a major problem during the Apollo missions. Dust would stick to the spacesuits, and could not be wiped off as predicted. Dust was brought back into the spacecraft, and was even inhaled by astronauts. This is a major health hazard. Atmospheric storms and other events can also cause dust to coat surfaces of spacecraft. This can cause abrasive damage to the craft. The coating can also reduce the effectiveness of thermal insulation and solar panels.' A group of engineers at Kennedy Space Center's Electrostatics and Surface Physics Laboratory have developed a new technology, called the Electrodynamic Dust Shield, to help alleviate these problems. It is based off of the electric curtain concept developed at NASA in 1967. "The EDS is an active dust mitigation technology that uses traveling electric fields to transport electrostatically charged dust particles along surfaces. To generate the traveling electric fields, the EDS consists of a multilayer dielectric coating with an embedded thin electrode grid running a multiphase low frequency AC signal. Electrostatically charged particles, such as those encountered on the moon, Mars, or an asteroid, are carried along by the traveling field due to the action of Coulomb and dielectrophoretic forces."2 The technical details have been described in a separate article. This document details the design and construction process of a small demonstration unit. Once finished, this device will go to the Office of the ChiefTechnologist at NASA headquarters, where it will be used to familiarize the public with the technology. 1 NASA KSC FO Intern, Prototype Development Laboratory, Kennedy Space Center, University of Central Florida Kennedy Space

Stankie, Charles G.

2013-01-01

297

Genetic Feature Subset Selection for Gender Classification: A Comparison Study  

Microsoft Academic Search

We consider the problem of gender classifica- tion from frontal facial images using genetic feature subset selection. We argue that feature selection is an important issue in gender classification and demonstrate that Genetic Algorithms (GA) can select good subsets of features (i.e., features that encode mostly gender information), reducing the classification error. First, Principal Component Analy- sis (PCA) is used

Zehang Sun; George Bebis; Xiaojing Yuan; Sushil J. Louis

2002-01-01

298

Spent fuel pyroprocessing demonstration  

SciTech Connect

A major element of the shutdown of the US liquid metal reactor development program is managing the sodium-bonded spent metallic fuel from the Experimental Breeder Reactor-II to meet US environmental laws. Argonne National Laboratory has refurbished and equipped an existing hot cell facility for treating the spent fuel by a high-temperature electrochemical process commonly called pyroprocessing. Four products will be produced for storage and disposal. Two high-level waste forms will be produced and qualified for disposal of the fission and activation products. Uranium and transuranium alloys will be produced for storage pending a decision by the US Department of Energy on the fate of its plutonium and enriched uranium. Together these activities will demonstrate a unique electrochemical treatment technology for spent nuclear fuel. This technology potentially has significant economic and technical advantages over either conventional reprocessing or direct disposal as a high-level waste option.

McFarlane, L.F.; Lineberry, M.J.

1995-05-01

299

Space Research Benefits Demonstrated  

NASA Technical Reports Server (NTRS)

An entranced youngster watches a demonstration of the enhanced resilience of undercooled metal alloys as compared to conventional alloys. Steel bearings are dropped onto plates made of steel, titanium alloy, and zirconium liquid metal alloy, so-called because its molecular structure is amorphous and not crystalline. The bearing on the liquid metal plate bounces for a minute or more longer than on the other plates. Experiments aboard the Space Shuttle helped scientists refine their understanding of the physical properties of certain metal alloys when undercooled (i.e., kept liquid below their normal solidification temperature). This new knowledge then allowed scientists to modify a terrestrial production method so they can now make limited quantities marketed under the Liquid Metal trademark. The exhibit was a part of the NASA outreach activity at AirVenture 2000 sponsored by the Experimental Aircraft Association in Oshkosh, WI.

2000-01-01

300

Shuttle bay telerobotics demonstration  

NASA Technical Reports Server (NTRS)

A demonstration of NASA's robotics capabilities should be a balanced agenda of servicing and assembly tasks combined with selected key technical experiments. The servicing tasks include refueling and module replacement. Refueling involves the mating of special fluid connectors while module replacement requires an array of robotic technologies such as special tools, the arm of a logistics tool, and the precision mating of orbital replacement units to guides. The assembly task involves the construction of a space station node and truss structure. The technological experiments will focus on a few important issues: the precision manipulation of the arms by a teleoperator, the additional use of several mono camera views in conjunction with the stereo system, the use of a general purpose end effector versus a caddy of tools, and the dynamics involved with using a robot with a stabilizer.

Chun, W.; Cogeos, P.

1987-01-01

301

Demonstrating An Epidemic  

NSDL National Science Digital Library

This experiment allows learners to experience a small scale "epidemic," demonstrating the ease with which disease organisms are spread, and enables learners to determine the originator of the "epidemic." Learners will transfer live bacteria by hand contact, then transfer an inoculum to a nutrient agar plate for 24 hour incubation. After incubation, plates are observed for growth of the microbial agent. By arranging the plates in the order of hand contact, it can be determined which individual received the original contaminant and started the "epidemic," which individuals transferred the organism yet did not grow it out (carriers), and how dosage, or amount of contamination, affects getting a disease. Other means of microbial transmission (air, water, body fluids, fomites) may also be discussed. This lesson guide includes safety precautions, questions, and an additional activity to simulate vaccination.

Powel, M. B.

2009-01-01

302

Fusion Power Demonstration III  

SciTech Connect

This is the third in the series of reports covering the Fusion Power Demonstration (FPD) design study. This volume considers the FPD-III configuration that incorporates an octopole end plug. As compared with the quadrupole end-plugged designs of FPD-I and FPD-II, this octopole configuration reduces the number of end cell magnets and shortens the minimum ignition length of the central cell. The end-cell plasma length is also reduced, which in turn reduces the size and cost of the end cell magnets and shielding. As a contiuation in the series of documents covering the FPD, this report does not stand alone as a design description of FPD-III. Design details of FPD-III subsystems that do not differ significantly from those of the FPD-II configuration are not duplicated in this report.

Lee, J.D. (ed.)

1985-07-01

303

ARJIS satellite demonstration project  

NASA Astrophysics Data System (ADS)

In 2003, the California Space Authority (CSA) was provided funding by the U. S. Congress through the Defense Appropriations Act to develop a project that would demonstrate the U.S. space enterprise capability that would contribute to the effectiveness of those engaged in Homeland Security. The project was given broad latitude in selecting the area of Homeland Security to be addressed and the nature of the space technology to be applied. CSA became aware of a nascent law enforcement data-sharing project in the San Diego region known as the Automated Regional Justice Information System (ARJIS). First developed by the police departments in San Diego, ARJIS is an innovative system that shares criminal justice information among 50 federal, state, and local agencies. ARJIS was completing a pilot project that enabled officers to receive information on handheld computers, which was transmitted wirelessly through cellular networks. The accessed information came from several databases that collectively contained the entire region's crime and arrest reports, traffic citations, and incidents, as well as state and county wants and warrants. The fundamental limitations that plague all cellular-based devices caught CSA's attention and resulted in a cooperative effort to harden the communications link between the patrol officer and critical data. The principal goal of the SATCOM development task was to create a proof-of-concept application that would use SATCOM links to augment the current ARJIS handheld wireless (cellular) capability. The successful technical demonstration and the positive support for satellite communications from the law enforcement community showed that this project filled a need-both for improved information sharing and for highly reliable communications systems.

Severance, Steve; Williams, Carl

2005-06-01

304

Orbital construction demonstration study  

NASA Technical Reports Server (NTRS)

A conceptual design and program plan for an Orbital Construction Demonstration Article (OCDA) was developed that can be used for evaluating and establishing practical large structural assembly operations. A flight plan for initial placement and continued utility is presented as a basic for an entirely new shuttle payload line-item having great future potential benefit for space applications. The OCDA is a three-axis stabilized platform in low-earth orbit with many structural nodals for mounting large construction and fabrication equipments. This equipment would be used to explore methods for constructing the large structures for future missions. The OCDA would be supported at regular intervals by the shuttle. Construction experiments and consumables resupply are performed during shuttle visit periods. A 250 kw solar array provides sufficient power to support the shuttle while attached to the OCDA and to run construction experiments at the same time. Wide band communications with a Telemetry and Data Relay Satellite compatible high gain antenna can be used between shuttle revisits to perform remote controlled, TV assisted construction experiments.

1976-01-01

305

NASA Bioreactor Demonstration System  

NASA Technical Reports Server (NTRS)

Leland W. K. Chung (left), Director, Molecular Urology Therapeutics Program at the Winship Cancer Institute at Emory University, is principal investigator for the NASA bioreactor demonstration system (BDS-05). With him is Dr. Jun Shu, an assistant professor of Orthopedics Surgery from Kuming Medical University China. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: Emory University.

2002-01-01

306

Technology demonstration solar telescope  

NASA Astrophysics Data System (ADS)

The conceptual design of the Large Earth-based Solar Telescope (LEST) has evolved through the years. In 1995-97 it was discussed whether a technology demonstration telescope could be built at a lower cost than the LEST originally proposed. In 1997, a de-scoped LEST design, the so-called "Mini-LEST", was conceived and proposed to the LEST community. The telescope has an innovative design with a small field lens that makes the way for simple adaptive optics. The optical performance is excellent. It has a low-cost alt-az steel structure with a large slewing ring for the azimuth movement and direct-drive motors for simplicity. The telescope is open but can easily be modified to a Helium telescope to compare performance of Helium filled telescopes vs. open telescopes. The tower has also been simplified to reduce cost. It has a dome design that provides protection for wind and yet permits open-air observations. The budget shows an overall cost of 37.6 MSEK and an exectution time of less than four years.

Andersen, Torben; Engvold, Oddbjrn; Owner-Pedersen, Mette

307

Plug cluster module demonstration  

NASA Technical Reports Server (NTRS)

The low pressure, film cooled rocket engine design concept developed during two previous ALRC programs was re-evaluated for application as a module for a plug cluster engine capable of performing space shuttle OTV missions. The nominal engine mixture ratio was 5.5 and the engine life requirements were 1200 thermal cycles and 10 hours total operating life. The program consisted of pretest analysis; engine tests, performed using residual components; and posttest analysis. The pretest analysis indicated that operation of the operation of the film cooled engine at O/F = 5.5 was feasible. During the engine tests, steady state wall temperature and performance measurement were obtained over a range of film cooling flow rates, and the durability of the engine was demonstrated by firing the test engine 1220 times at a nominal performance ranging from 430 - 432 seconds. The performance of the test engine was limited by film coolant sleeve damage which had occurred during previous testing. The post-test analyses indicated that the nominal performance level can be increased to 436 seconds.

Rousar, D. C.

1978-01-01

308

Airway hyperresponsiveness is associated with airway remodeling but not inflammation in aging Cav1-/- mice  

PubMed Central

Background Airway inflammation and airway remodeling are the key contributors to airway hyperresponsiveness (AHR), a characteristic feature of asthma. Both processes are regulated by Transforming Growth Factor (TGF)-?. Caveolin 1 (Cav1) is a membrane bound protein that binds to a variety of receptor and signaling proteins, including the TGF-? receptors. We hypothesized that caveolin-1 deficiency promotes structural alterations of the airways that develop with age will predispose to an increased response to allergen challenge. Methods AHR was measured in Cav1-deficient and wild-type (WT) mice 1 to 12 months of age to examine the role of Cav1 in AHR and the relative contribution of inflammation and airway remodeling. AHR was then measured in Cav1-/- and WT mice after an ovalbumin-allergen challenge performed at either 2 months of age, when remodeling in Cav1-/- and WT mice was equivalent, and at 6 months of age, when the Cav1-/- mice had established airway remodeling. Results Cav1-/- mice developed increased thickness of the subepithelial layer and a correspondingly increased AHR as they aged. In addition, allergen-challenged Cav1-/- mice had an increase in AHR greater than WT mice that was largely independent of inflammation. Cav1-/- mice challenged at 6 months of age have decreased AHR compared to those challenged at 2 months with correspondingly decreased BAL IL-4 and IL-5 levels, inflammatory cell counts and percentage of eosinophils. In addition, in response to OVA challenge, the number of goblet cells and ?-SMA positive cells in the airways were reduced with age in response to OVA challenge in contrast to an increased collagen deposition further enhanced in absence of Cav1. Conclusion A lack of Cav1 contributed to the thickness of the subepithelial layer in mice as they aged resulting in an increase in AHR independent of inflammation, demonstrating the important contribution of airway structural changes to AHR. In addition, age in the Cav1-/- mice is a contributing factor to airway remodeling in the response to allergen challenge.

2013-01-01

309

Features of Alpine Glaciation  

NSDL National Science Digital Library

This page shows a sketch color graphic of alpine valley glaciation with the features: horn, col, arrete, cirque, glacial trough, crevasse, and hanging valley. Users can click on the sidebar for each feature to get a three dimensional thumbnail animation illustrating the process.

Mustoe, M.

310

Formation of Oceanic Features  

NSDL National Science Digital Library

This is a picture inquiry based lesson for students to explore four specific oceanic features (mid-ocean ridge, trench, seamount, and continental shelf). Groups of three students will observe and explain features found in pictures and share ideas with their peers.

Wicks, Katlyn

2012-07-16

311

Features of similarity  

Microsoft Academic Search

Questions the metric and dimensional assumptions that underlie the geometric representation of similarity on both theoretical and empirical grounds. A new set-theoretical approach to similarity is developed in which objects are represented as collections of features and similarity is described as a feature-matching process. Specifically, a set of qualitative assumptions is shown to imply the contrast model, which expresses the

Amos Tversky

1977-01-01

312

Apollo 14 composite casting demonstration  

NASA Technical Reports Server (NTRS)

This program assisted in the design and implementation of the composite casting demonstration for the Apollo 14 mission. Both flight and control samples were evaluated. Some conclusions resulting from a comparison of the flight and control samples were: (1) Solidification in neither the flight nor control samples was truly directional. (2) Apparent intermittent contact of the melt with the container in the flight samples led to unusual nucleation and growth structures. (3) There was greater uniformity, on a macro scale, of both pores and structural features in the flight sample; presumably the result of the reduced gravity conditions. (4) It seems quite feasible to produce enhanced dispersions of gases and dense phases in a melt which is solidified in reduced gravity. (5) A two-stage heating/cooling cycle may help directional solidification. (6) Sample materials should be selected from materials in which the dispersant fully wets the matrix material. (7) Experiments should be conducted in two modes: (1) where the melt is in good thermal contact with the container, and (2) where the melt is in a free-float condition.

1971-01-01

313

Engineering Humanized Mice for Improved Hematopoietic Reconstitution  

PubMed Central

Humanized mice are immunodeficient mice engrafted with human hematopoietic stem cells that give rise to various lineages of human blood cells throughout the life of the animal. This article reviews recent advances in the generation of humanized mice, focusing on practical considerations. We discuss features of different immunodeficient recipient mouse strains, sources of human hematopoietic stem cells, advances in expansion and genetic modification of hematopoietic stem cells, and techniques to modulate the cytokine environment of recipient mice in order to enhance reconstitution of specific human blood lineage cells. We highlight the opportunities created by new technologies and discuss practical considerations on how to make best use of the widening array of basic models for specific research applications.

Drake, Adam C; Chen, Qingfeng; Chen, Jianzhu

2014-01-01

314

VLBI2010 Demonstrator Project  

NASA Astrophysics Data System (ADS)

The next generation geodetic VLBI instrument is being developed with a goal of 1 mm position uncertainty in twenty-four hours. Knowing that spatial and temporal fluctuations in the atmosphere delay are a major component of the error in position determination, the VLBI2010 committee has carried out a large number of simulations to arrive at design goals for the antenna system. These goals are fast slewing antennas and high delay precision per observation. With existing and anticipated data recording capabilities, these translate to an antenna diameter of 12 m or larger and a per-observation delay precision of approximately 4 psec. The major innovation for the VLBI2010 concept that allows the use of relatively small antennas to achieve these goals is the proposal to observe in four frequency bands, instead of the two currently used, in order to gain the higher precision of phase delays compared to the group delay. The other advance that enables the use of small antennas is the significant increase in data acquisition rates that has been made possible by the development of disk-based recorders and digital back ends. To evaluate this concept, a prototype of the feed-to-recorder system has been implemented by the Broadband Development Team* on two antennas, the 5 m MV-3 antenna at Goddard Space Flight Center near Washington, D.C., and the 18 m Westford antenna at Haystack Observatory near Boston. The system includes a broadband feed and low noise amplifiers covering the range approximately 2 GHz to 13 GHz, all cooled to 20K; a newly developed phase calibration generator; a flexible local oscillator (LO) that allows selection of any band in the range of the feed/LNAs; Digital Back End; and a disk-based recorder capable of a sustained rate of 2 gigabits per second (gbps). Four sets of the LO/DBE/recorder chain are used at each antenna to give a total record rate of 8 gbps. The systems have been successfully used in the band 8.5 to 9 GHz with one set of the recorder chain. Observations demonstrating the full four-band configuration are planned for October. In this talk the results of these tests, the improvements that are anticipated for the operational VLBI2010 network, and the status of other developments in the next generation of geodetic VLBI systems will be presented. * Bruce Whittier, Mike Titus, Jason SooHoo, Dan Smythe, Alan Rogers, Jay Redmond, Mike Poirier, Chuck Kodak, Alan Hinton, Ed Himwich, Skip Gordon, Mark Evangelista, Irv Diegel, Brian Corey, Tom Clark, Chris Beaudoin (in reverse alphabetical order)

Niell, A.

2008-12-01

315

Spatial Feature Evaluation for Aerial Scene Analysis  

SciTech Connect

High-resolution aerial images are becoming more readily available, which drives the demand for robust, intelligent and efficient systems to process increasingly large amounts of image data. However, automated image interpretation still remains a challenging problem. Robust techniques to extract and represent features to uniquely characterize various aerial scene categories is key for automated image analysis. In this paper we examined the role of spatial features to uniquely characterize various aerial scene categories. We studied low-level features such as colors, edge orientations, and textures, and examined their local spatial arrangements. We computed correlograms representing the spatial correlation of features at various distances, then measured the distance between correlograms to identify similar scenes. We evaluated the proposed technique on several aerial image databases containing challenging aerial scene categories. We report detailed evaluation of various low-level features by quantitatively measuring accuracy and parameter sensitivity. To demonstrate the feature performance, we present a simple query-based aerial scene retrieval system.

Swearingen, Thomas S [ORNL] [ORNL; Cheriyadat, Anil M [ORNL] [ORNL

2013-01-01

316

Time Varying Feature Data  

NASA Astrophysics Data System (ADS)

The infrastructure to gather, store and access information about our environment is improving and growing rapidly. The increasing amount of information allows us to get a better understanding of the current state of our environment, historical processes and to simulate and predict the future state of the environment. Finer grained spatial and temporal data and more reliable communications make it easier to model dynamic states and ephemeral features. The exchange of information within and across geospatial domains is facilitated through the use of harmonized information models. The Observations & Measurements (O&M) developed through OGC and standardised by ISO is an example of such a cross-domain information model. It is used in many domains, including meteorology, hydrology as well as the emergency management. O&M enables harmonized representation of common metadata that belong to the act of determining the state of a feature property, whether by sensors, simulations or humans. In addition to the resulting feature property value, information such as the result quality but especially the time that the result applies to the feature property can be represented. Temporal metadata is critical to modelling past and future states of a feature. The features, and the semantics of each property, are defined in domain specific Application Schema using the General Feature Model (GFM) from ISO 19109 and usually encoded following ISO 19136. However, at the moment these standards provide only limited support for the representation and handling of time varying feature data. Features like rivers, wildfires or gas plumes have a defined state - for example geographic extent - at any given point in time. To keep track of changes, a more complex model for example using time-series coverages is required. Furthermore, the representation and management of feature property value changes via the service interfaces defined by OGC and ISO - namely: WFS and WCS - would be rather complex. Keeping track of feature property value corrections or even feature (state change) cancellations for auditing purposes is also not easy to achieve. The aviation domain has strong requirements to represent and manage the state of aeronautical features through time. Being able to efficiently encode and manage feature state changes, keeping track of all changes for auditing purposes and being able to determine the future state of an aeronautical feature as currently known to the system are vital for aeronautical applications. In order to support these requirements, the Aeronautical Information Exchange Model (AIXM) which has been developed by the aviation domain is based on the so called AIXM Temporality Model (AIXM-TM). The AIXM-TM defines various rules for modeling, representing and handling the state of aeronautical features through time. This is a promising approach that can be incorporated into the GFM so that ultimately the modeling and management of time varying feature data is supported in an interoperable and harmonized way in all geospatial domains. This presentation gives an introduction to the main concepts of the AIXM-TM. It also shows how the GFM can be extended to support time varying feature data. Finally, the relationship of O&M and time varying features is discussed.

Echterhoff, J.; Simonis, I.; Atkinson, R.

2012-04-01

317

Feature Transformation And Subset Selection  

Microsoft Academic Search

uction and feature extraction. Bothare sometimes called feature discovery. Assuming the original set consists of A 1 ; A 2 ; :::; A nfeatures, these variants can be defined below.Feature construction is a process that discovers missing information about the relationshipsbetween features and augments the space of features by inferring or creatingadditional features [5, 7, 6]. After feature construction, we

Huan Liu; Hiroshi Motoda

1998-01-01

318

Favorite Demonstrations: Gaseous Diffusion: A Demonstration of Graham's Law.  

ERIC Educational Resources Information Center

Describes a demonstration in which gaseous ammonia and hydrochloric acid are used to illustrate rates of diffusion (Graham's Law). Simple equipment needed for the demonstration include a long tube, rubber stoppes, and cotton. Two related demonstrations are also explained. (DH)

Kauffman, George B.; Ebner, Ronald D.

1985-01-01

319

New features in MEDM.  

SciTech Connect

MEDM, which is derived from Motif Editor and Display Manager, is the primary graphical interface to the EPICS control system. This paper describes new features that have been added to MEDM in the last two years. These features include new editing capabilities, a PV Info dialog box, a means of specifying limits and precision, a new implementation of the Cartesian Plot, new features for several objects, new capability for the Related Display, help, a user-configurable Execute Menu, reconfigured start-up options, and availability for Windows 95/98/NT. Over one hundred bugs have been fixed, and the program is quite stable and in extensive use.

Evans, K., Jr.

1999-04-13

320

Mice Drawer System: phase c/d development and perspective.  

PubMed

MDS (Mice Drawer System) is the Facility that will support the research on board the International Space Station (ISS). Funded by ASI with Laben as industrial Prime Contractor, MDS will also permit its utilisation for other research programs with mice. The most attractive feature of MDS is that six mice can he kept separate inside dedicated and isolated cages. This permits to perform six experiments in parallel, one for each mouse. In the first utilisation flight of MDS facility the selected experiment is devoted to study human bone formation and specific countermeasures to prevent osteoporosis using mice under microgravity conditions as a model. PMID:15002603

Cancedda, Ranieri; Pignataro, Salvatore; Alberici, Giovanni; Tenconi, Chiara

2002-07-01

321

FeaturePlugin: feature modeling plug-in for Eclipse  

Microsoft Academic Search

Feature modeling is a key technique used in product-line development to model commonalities and variabilities of product-line members. In this paper, we present FeaturePlugin, a feature modeling plug-in for Eclipse. The tool supports cardinality-based feature modeling, specialization of feature diagrams, and configuration based on feature diagrams.

Michal Antkiewicz; Krzysztof Czarnecki

2004-01-01

322

Volcanic features of Io  

USGS Publications Warehouse

Volcanic activity is apparently higher on Io than on any other body in the Solar System. Its volcanic landforms can be compared with features on Earth to indicate the type of volcanism present on Io. ?? 1979 Nature Publishing Group.

Carr, M. H.; Masursky, H.; Strom, R. G.; Terrile, R. J.

1979-01-01

323

Icariin, a phoshphodiesterase-5 inhibitor, improves learning and memory in APP/PS1 transgenic mice by stimulation of NO/cGMP signalling.  

PubMed

Phosphodiesterase-5 (PDE5) inhibitors are predominantly used in the treatment of erectile dysfunction, and have been recently shown to have a potential therapeutic effect for the treatment of Alzheimer's disease (AD) through stimulation of nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) signalling by elevating cGMP, which is a secondary messenger involved in processes of neuroplasticity. In the present study, the effects of a PDE5 inhibitor, icarrin (ICA), on learning and memory as well as the pathological features in APP/PS1 transgenic AD mice were investigated. Ten-month-old APP/PS1 transgenic mice overexpressing human amyloid precursor protein (APP695swe) and presenilin 1 (PS1-dE9) were given ICA (30 and 60 mg/kg) or sildenafil (SIL) (2 mg/kg), age-matched wild-type (WT) mice were given ICA (60 mg/kg), and APP/PS1 and WT control groups were given an isovolumic vehicle orally twice a day for four months. Results demonstrated that ICA treatments significantly improved learning and memory of APP/PS1 transgenic mice in Y-maze tasks. The amyloid precursor protein (APP), amyloid-beta (A?1-40/42) and PDE5 mRNA and/or protein levels were increased in the hippocampus and cortex of APP/PS1 mice, and ICA treatments decreased these physiopathological changes. Furthermore, ICA-treated mice showed an increased expression of three nitric oxide synthase (NOS) isoforms at both mRNA and protein levels, together with increased NO and cGMP levels in the hippocampus and cortex of mice. These findings demonstrate that ICA improves learning and memory functions in APP/PS1 transgenic mice possibly through the stimulation of NO/cGMP signalling and co-ordinated induction of NOS isoforms. PMID:24513083

Jin, Feng; Gong, Qi-Hai; Xu, Ya-Sha; Wang, Li-Na; Jin, Hai; Li, Fei; Li, Li-Sheng; Ma, Yue-Ming; Shi, Jing-Shan

2014-06-01

324

Molecular, Physiological, and Motor Performance Defects in DMSXL Mice Carrying >1,000 CTG Repeats from the Human DM1 Locus  

PubMed Central

Myotonic dystrophy type 1 (DM1) is caused by an unstable CTG repeat expansion in the 3?UTR of the DM protein kinase (DMPK) gene. DMPK transcripts carrying CUG expansions form nuclear foci and affect splicing regulation of various RNA transcripts. Furthermore, bidirectional transcription over the DMPK gene and non-conventional RNA translation of repeated transcripts have been described in DM1. It is clear now that this disease may involve multiple pathogenic pathways including changes in gene expression, RNA stability and splicing regulation, protein translation, and micro–RNA metabolism. We previously generated transgenic mice with 45-kb of the DM1 locus and >300 CTG repeats (DM300 mice). After successive breeding and a high level of CTG repeat instability, we obtained transgenic mice carrying >1,000 CTG (DMSXL mice). Here we described for the first time the expression pattern of the DMPK sense transcripts in DMSXL and human tissues. Interestingly, we also demonstrate that DMPK antisense transcripts are expressed in various DMSXL and human tissues, and that both sense and antisense transcripts accumulate in independent nuclear foci that do not co-localize together. Molecular features of DM1-associated RNA toxicity in DMSXL mice (such as foci accumulation and mild missplicing), were associated with high mortality, growth retardation, and muscle defects (abnormal histopathology, reduced muscle strength, and lower motor performances). We have found that lower levels of IGFBP-3 may contribute to DMSXL growth retardation, while increased proteasome activity may affect muscle function. These data demonstrate that the human DM1 locus carrying very large expansions induced a variety of molecular and physiological defects in transgenic mice, reflecting DM1 to a certain extent. As a result, DMSXL mice provide an animal tool to decipher various aspects of the disease mechanisms. In addition, these mice can be used to test the preclinical impact of systemic therapeutic strategies on molecular and physiological phenotypes.

Huguet, Aline; Medja, Fadia; Nicole, Annie; Vignaud, Alban; Guiraud-Dogan, Celine; Ferry, Arnaud; Decostre, Valerie; Hogrel, Jean-Yves; Metzger, Friedrich; Hoeflich, Andreas; Baraibar, Martin; Gomes-Pereira, Mario; Puymirat, Jack; Bassez, Guillaume; Furling, Denis; Munnich, Arnold; Gourdon, Genevieve

2012-01-01

325

Alkaline Phosphatase Knock-Out Mice Recapitulate the Metabolic and Skeletal Defects of Infantile Hypophosphatasia*  

PubMed Central

Hypophosphatasia is an inborn error of metabolism characterized by deficient activity of the tissue-nonspecific isoenzyme of alkaline phosphatase (TNSALP) and skeletal disease due to impaired mineralization of cartilage and bone matrix. We investigated two independently generated TNSALP gene knock-out mouse strains as potential models for hypophosphatasia. Homozygous mice (?/?) had < 1% of wild-type plasma TNSALP activity; heterozygotes had the predicted mean of ~50%. Phosphoethanolamine, inorganic pyrophosphate, and pyridoxal 5?-phosphate are putative natural substrates for TNSALP and all were increased endogenously in the knock-out mice. Skeletal disease first appeared radiographically at ~10 days of age and featured worsening rachitic changes, osteopenia, and fracture. Histologic studies revealed developmental arrest of chondrocyte differentiation in epiphyses and in growth plates with diminished or absent hypertrophic zones. Progressive osteoidosis from defective skeletal matrix mineralization was noted but not associated with features of secondary hyperparathyroidism. Plasma and urine calcium and phosphate levels were unremarkable. Our findings demonstrate that TNSALP knock-out mice are a good model for the infantile form of hypophosphatasia and provide compelling evidence for an important role for TNSALP in postnatal development and mineralization of the murine skeleton.

FEDDE, KENTON N.; BLAIR, LIBBY; SILVERSTEIN, JULIE; COBURN, STEPHEN P.; RYAN, LAWRENCE M.; WEINSTEIN, ROBERT S.; WAYMIRE, KATRINA; NARISAWA, SONOKO; MILLAN, JOSE L.; MACGREGOR, GRANT R.; WHYTE, MICHAEL P.

2011-01-01

326

Dynamics of feature categorization.  

PubMed

In visual and auditory scenes, we are able to identify shared features among sensory objects and group them according to their similarity. This grouping is preattentive and fast and is thought of as an elementary form of categorization by which objects sharing similar features are clustered in some abstract perceptual space. It is unclear what neuronal mechanisms underlie this fast categorization. Here we propose a neuromechanistic model of fast feature categorization based on the framework of continuous attractor networks. The mechanism for category formation does not rely on learning and is based on biologically plausible assumptions, for example, the existence of populations of neurons tuned to feature values, feature-specific interactions, and subthreshold-evoked responses upon the presentation of single objects. When the network is presented with a sequence of stimuli characterized by some feature, the network sums the evoked responses and provides a running estimate of the distribution of features in the input stream. If the distribution of features is structured into different components or peaks (i.e., is multimodal), recurrent excitation amplifies the response of activated neurons, and categories are singled out as emerging localized patterns of elevated neuronal activity (bumps), centered at the centroid of each cluster. The emergence of bump states through sequential, subthreshold activation and the dependence on input statistics is a novel application of attractor networks. We show that the extraction and representation of multiple categories are facilitated by the rich attractor structure of the network, which can sustain multiple stable activity patterns for a robust range of connectivity parameters compatible with cortical physiology. PMID:23020108

Martí, Daniel; Rinzel, John

2013-01-01

327

The MICE luminosity monitor  

NASA Astrophysics Data System (ADS)

The MICE experiment will provide the first measurement of ionisation cooling, a technique suitable for reducing the transverse emittance of a tertiary muon beam in a future neutrino factory accelerator facility. MICE is presently in the final stages of commissioning its beam line. The MICE luminosity monitor has proved an invaluable tool throughout this process, providing independent measurements of particle rate from the MICE target, normalisation for beam line detectors and verification of simulation codes.

Dobbs, A.; Forrest, D.; Soler, F. J. P.

2013-02-01

328

Enhanced osteopontin expression and macrophage infiltration in MRL-Fas(lpr) mice with lupus nephritis.  

PubMed

MRL-Fas(lpr) mice spontaneously develop a chronic lupus-like renal disease, characterized by immune complex-mediated glomerulonephritis and abundant mononuclear cell infiltration in the interstitium. In the present study we have examined whether the macrophage chemoattractant osteopontin (Opn) could be important in the recruitment of macrophages in this murine model of autoimmune renal injury. We have examined the expression of Opn in the kidney of MRL-Fas(lpr) mice and have correlated Opn synthesis with the degree of macrophage infiltration. Immunofluorescence staining revealed prominent expression of Opn by proximal tubules in MRL-Fas(lpr) mice but not in MRL-++ control mice. Northern blot analysis demonstrated that steady-state transcript levels for Opn mRNA were also significantly increased in MRL-Fas(lpr) kidneys compared with control kidneys. Furthermore, in situ hybridization showed massive Opn mRNA transcripts in proximal tubules in MRL-Fas(lpr) mice but not in controls. The diffuse macrophage infiltration in the kidney of MRL-Fas(lpr) correlated with the enhanced Opn expression. Opn secretion in vitro by cultured renal tubular epithelial cells was upregulated by TNF-alpha and 1,25(OH)2-vitamin D3, whereas no regulation was observed in a control macrophage cell line. We conclude that the enhanced expression of the chemotactic molecule Opn by tubular cells is a prominent feature of murine lupus nephritis and might be promoted by the proinflammatory cytokine environment in MRL-Fas(lpr). The chronic upregulation of Opn could participate in the recruitment of monocytes in the kidney of MRL-Fas(lpr) mice, thereby contributing to the pathogenesis of autoimmune renal disease. PMID:9867126

Wüthrich, R P; Fan, X; Ritthaler, T; Sibalic, V; Yu, D J; Loffing, J; Kaissling, B

1998-01-01

329

Lupus-prone mice as models to study xenobiotic-induced acceleration of systemic autoimmunity.  

PubMed Central

The linkage between xenobiotic exposures and autoimmune diseases remains to be clearly defined. However, recent studies have raised the possibility that both genetic and environmental factors act synergistically at several stages or checkpoints to influence disease pathogenesis in susceptible populations. These observations predict that individuals susceptible to spontaneous autoimmunity should be more susceptible following xenobiotic exposure by virtue of the presence of predisposing background genes. To test this possibility, mouse strains with differing genetic susceptibility to murine lupus were examined for acceleration of autoimmune features characteristic of spontaneous systemic autoimmune disease following exposure to the immunostimulatory metals nickel and mercury. Although NiCl(2) exposure did not exacerbate autoimmunity, HgCl(2) significantly accelerated systemic disease in a strain-dependent manner. Mercury-exposed (NZB X NZW)F1 mice had accelerated lymphoid hyperplasia, hypergammaglobulinemia, autoantibodies, and immune complex deposits. Mercury also exacerbated immunopathologic manifestations in MRL+/+ and MR -lpr mice. However, there was less disease acceleration in lpr mice compared with MRL+/+ mice, likely due to the fact that environmental factors are less critical for disease induction when there is strong genetic susceptibility. Non-major histocompatibility complex genes also contributed to mercury-exacerbated disease, as the nonautoimmune AKR mice, which are H-2 identical with the MRL, showed less immunopathology than either the MRL/lpr or MRL+/+ strains. This study demonstrates that genetic susceptibility to spontaneous systemic autoimmunity can be a predisposing factor for HgCl(2)-induced exacerbation of autoimmunity. Such genetic predisposition may have to be considered when assessing the immunotoxicity of xenobiotics. Additional comparative studies using autoimmune-prone and nonautoimmune mice strains with different genetic backgrounds will help determine the contribution that xenobiotic exposure makes in rendering sensitive populations susceptible to autoimmune diseases.

Pollard, K M; Pearson, D L; Hultman, P; Hildebrandt, B; Kono, D H

1999-01-01

330

Pharmacological inhibition of PPAR? increases osteoblastogenesis and bone mass in male C57BL/6 mice.  

PubMed

Infiltration of bone marrow with fat is a prevalent feature in people with age-related bone loss and osteoporosis, which correlates inversely with bone formation and positively with high expression levels of peroxisomal proliferator-activated receptor gamma (PPAR?). Inhibition of PPAR? thus represents a potential therapeutic approach for age-related bone loss. In this study, we examined the effect of PPAR? inhibition on bone in skeletally mature C57BL/6 male mice. Nine-month-old mice were treated with a PPAR? antagonist, bisphenol-A-diglycidyl ether (BADGE), alone or in combination with active vitamin D (1,25[OH](2) D(3) ) for 6 weeks. Micro-computed tomography and bone histomorphometry indicated that mice treated with either BADGE or BADGE?+?1,25(OH)(2) D(3) had significantly increased bone volume and improved bone quality compared with vehicle-treated mice. This phenotype occurred in the absence of alterations in osteoclast number. Furthermore, the BADGE?+?1,25(OH)(2) D(3) -treated mice exhibited higher levels of unmineralized osteoid. All of the treated groups showed a significant increase in circulating levels of bone formation markers without changes in bone resorption markers, while blood glucose, parathyroid hormone, and Ca(+) remained normal. Furthermore, treatment with BADGE induced higher levels of expression of vitamin D receptor within the bone marrow. Overall, treated mice showed higher levels of osteoblastogenesis and bone formation concomitant with decreased marrow adiposity and ex vivo adipogenesis. Taken together, these observations demonstrate that pharmacological inhibition of PPAR? may represent an effective anabolic therapy for osteoporosis in the near future. PMID:23044841

Duque, Gustavo; Li, Wei; Vidal, Christopher; Bermeo, Sandra; Rivas, Daniel; Henderson, Janet

2013-03-01

331

Xenobiotic acceleration of idiopathic systemic autoimmunity in lupus-prone bxsb mice.  

PubMed Central

The diverse genetic backgrounds of lupus-prone murine models, which produce both quantitative and qualitative differences in disease expression, may be a valuable resource for studying the influence of environmental exposure on autoimmune disease in sensitive populations. We tested this premise by exposing autoimmune-prone BXSB and the nonautoimmune C57BL/6 mice to the heavy metal mercury. Although both strains express a nonsusceptible H-2 haplotype, exposure to mercury accelerated systemic autoimmunity in both male and female BXSB mice, whereas the C57BL/6 mice were resistant. The subclasses of antichromatin antibodies elicited in BXSB mice by mercury exposure were more consistent with the predominant Th1-type response of idiopathic disease than with the Th2-type response found in mercury-induced autoimmunity (HgIA). The appearance and magnitude of both humoral and cellular features of systemic autoimmunity correlated with the mercury dose. Furthermore, environmentally relevant tissue levels of mercury were associated with exacerbated systemic autoimmunity. These studies demonstrate that xenobiotic exposure can accelerate spontaneous systemic autoimmunity, and they support the possibility that low-level xenobiotic exposure enhances susceptibility to systemic autoimmunity in genetically susceptible individuals.

Pollard, K M; Pearson, D L; Hultman, P; Deane, T N; Lindh, U; Kono, D H

2001-01-01

332

Behavioral and neural correlates of acute and scheduled hunger in C57BL/6 mice.  

PubMed

In rodents, daily feeding schedules induce food anticipatory activity (FAA) rhythms with formal properties suggesting mediation by food-entrained circadian oscillators (FEOs). The search for the neuronal substrate of FEOs responsible for FAA is an active area of research, but studies spanning several decades have yet to identify unequivocally a brain region required for FAA. Variability of results across studies leads to questions about underlying biology versus methodology. Here we describe in C57BL/6 male mice the effects of varying the 'dose' of caloric restriction (0%, 60%, 80%, 110%) on the expression of FAA as measured by a video-based analysis system, and on the induction of c-Fos in brain regions that have been implicated in FAA. We determined that more severe caloric restriction (60%) leads to a faster onset of FAA with increased magnitude. Using the 60% caloric restriction, we found little evidence for unique signatures of neuronal activation in the brains of mice anticipating a daily mealtime compared to mice that were fasted acutely or fed ad-libitum-even in regions such as the dorsomedial and ventrolateral hypothalamus, nucleus accumbens, and cerebellum that have previously been implicated in FAA. These results underscore the importance of feeding schedule parameters in determining quantitative features of FAA in mice, and demonstrate dissociations between behavioral FAA and neural activity in brain areas thought to harbor FEOs or participate in their entrainment or output. PMID:24806659

Gallardo, Christian M; Hsu, Cynthia T; Gunapala, Keith M; Parfyonov, Maksim; Chang, Chris H; Mistlberger, Ralph E; Steele, Andrew D

2014-01-01

333

Behavioral and Neural Correlates of Acute and Scheduled Hunger in C57BL/6 Mice  

PubMed Central

In rodents, daily feeding schedules induce food anticipatory activity (FAA) rhythms with formal properties suggesting mediation by food-entrained circadian oscillators (FEOs). The search for the neuronal substrate of FEOs responsible for FAA is an active area of research, but studies spanning several decades have yet to identify unequivocally a brain region required for FAA. Variability of results across studies leads to questions about underlying biology versus methodology. Here we describe in C57BL/6 male mice the effects of varying the ‘dose’ of caloric restriction (0%, 60%, 80%, 110%) on the expression of FAA as measured by a video-based analysis system, and on the induction of c-Fos in brain regions that have been implicated in FAA. We determined that more severe caloric restriction (60%) leads to a faster onset of FAA with increased magnitude. Using the 60% caloric restriction, we found little evidence for unique signatures of neuronal activation in the brains of mice anticipating a daily mealtime compared to mice that were fasted acutely or fed ad-libitum–even in regions such as the dorsomedial and ventrolateral hypothalamus, nucleus accumbens, and cerebellum that have previously been implicated in FAA. These results underscore the importance of feeding schedule parameters in determining quantitative features of FAA in mice, and demonstrate dissociations between behavioral FAA and neural activity in brain areas thought to harbor FEOs or participate in their entrainment or output.

Gunapala, Keith M.; Parfyonov, Maksim; Chang, Chris H.; Mistlberger, Ralph E.; Steele, Andrew D.

2014-01-01

334

The effects of hypermuscularity on shoulder morphology in myostatin-deficient mice  

PubMed Central

Mechanical loads, particularly those generated by skeletal muscle, play a significant role in determining long-bone shape and strength, but it is less clear how these loads influence the morphology of flat bones like the scapula. While scapular morphology has been shown to vary with locomotor mode in mammals, this study seeks to better understand whether genetically modified muscle size can influence scapular shape in the absence of significant locomotor differences. The soft- and hard-tissue morphological characteristics were examined in 11 hypermuscular, mutant (myostatin-deficient), 20 heterozygote, and 15 wild-type mouse shoulders. Body mass did not significantly differ among the genotype groups, but homozygous mutant and heterozygote mice had significantly larger shoulder muscles than wild-type mice. Mutant mice also differed significantly from the wild-type controls in several aspects of scapular size and shape, including glenohumeral joint orientation, total scapular length, superior border length, and supraspinous and infraspinous fossa length. Conversely, several traits describing superoinferior scapular breadth measures (e.g. total breadth and dorsal scapular fossa breadth) did not significantly differ between mutant and wild-type mice. Since the intrinsic musculature of the scapula is oriented in a mediolateral fashion, it follows that mediolaterally configured hard-tissue features like scapular length were most distinct among genotype groups. As had been noted previously with long bones, this study demonstrates that genetically enhanced muscle size has marked effects on the morphological characteristics of the shoulder.

Green, David J; Hamrick, Mark W; Richmond, Brian G

2011-01-01

335

Esophageal Cancer - Featured Clinical Trials  

Cancer.gov

Esophageal Cancer - Featured Clinical Trials The following list shows Featured Clinical Trials for a specific type of cancer. You may also want to view: Multiple Cancer Types - Featured Clinical Trials Supportive Care - Featured Clinical Trials Related

336

Skin Cancer - Featured Clinical Trials  

Cancer.gov

Skin Cancer - Featured Clinical Trials The following list shows Featured Clinical Trials for a specific type of cancer. You may also want to view: Multiple Cancer Types - Featured Clinical Trials Supportive Care - Featured Clinical Trials

337

Thyroid Cancer - Featured Clinical Trials  

Cancer.gov

Thyroid Cancer - Featured Clinical Trials The following list shows Featured Clinical Trials for a specific type of cancer. You may also want to view: Multiple Cancer Types - Featured Clinical Trials Supportive Care - Featured Clinical Trials

338

Virtual MICE Promotion  

Microsoft Academic Search

Hong Kong and Singapore have been the leading cities for hosting MICE in Asia. Every year, thousands of events are held, both by local and international organizers, in Singapore and Hong Kong. Despite the significant economic contributions of MICE to a local economy, hospitality and tourism literature seldom analyzes Hong Kong and Singapore in terms of MICE promotion. The absence

Catherine Cheung; Rob Law

2002-01-01

339

Diaphragm muscle sarcopenia in aging mice.  

PubMed

Sarcopenia, defined as muscle weakness and fiber atrophy, of respiratory muscles such as the diaphragm (DIAm) has not been well characterized. The DIAm is the main inspiratory muscle and knowledge of DIAm sarcopenia is important for establishing the effects of aging on respiratory function. We hypothesized that aging is associated with a loss of DIAm force and reduced fiber cross-sectional area (CSA), and that these changes vary across fiber types. DIAm sarcopenia was assessed in young (5 month; n = 11) and old (23 month; n = 12) wild-type mice reflecting ~100 and 75% survival, respectively. In addition, DIAm sarcopenia was evaluated in BubR1(H/H) mice (n = 4) that display accelerated aging (~60% survival at 5 months) as a result of expression of a hypomorphic allele (H) of the mitotic checkpoint protein BubR1. Maximum specific force (normalized for CSA) of the DIAm was 34% less in old mice and 57% lower in BubR1(H/H) mice compared to young mice. Mean CSA of type IIx and/or IIb DIAm fibers was 27% smaller in old wild-type mice and 47% smaller in BubR1(H/H) mice compared to young mice. Mean CSA of type I or IIa fibers was not different between groups. Collectively these results demonstrate sarcopenia of the DIAm in aging wild-type mice and in BubR1(H/H) mice displaying accelerated aging. Sarcopenia may limit the ability of the DIAm to accomplish expulsive, non-ventilatory behaviors essential for airway clearance. As a result, these changes in the DIAm may contribute to respiratory complications with aging. PMID:23792145

Greising, Sarah M; Mantilla, Carlos B; Gorman, Britney A; Ermilov, Leonid G; Sieck, Gary C

2013-09-01

340

Automated localization of retinal features.  

PubMed

Retinal fundus images are widely used in the diagnosis and treatment of various eye diseases, such as diabetic retinopathy and glaucoma. A computer-aided retinal fundus image analysis could provide an immediate detection and characterization of retinal features prior to specialist inspection. This paper proposes an approach to automatically localize the main features in fundus images, such as blood vessels, optic disc, and fovea by exploiting the spatial and geometric relations that govern their distribution within the fundus image. The blood vessels are segmented by scale-space analysis. The average thickness of these blood vessels is then computed using the vessels centerlines and orientations from a Hessian matrix. The optic disc is localized using the circular Hough transform, the parabolic Hough transform fitting, and the localization of the fovea. The proposed method can be extended to establish a foveal coordinate system to facilitate grading lesions based on the spatial relationships between lesions and landmark features. The proposed method was evaluated on publicly available image databases, and the results have demonstrated a significant improvement over the current state-of-the-art methods. PMID:21743504

Sekhar, Sribalamurugan; Abd El-Samie, Fathi E; Yu, Pan; Al-Nuaimy, Waleed; Nandi, Asoke K

2011-07-01

341

Feature-selected tree-based classification.  

PubMed

Feature selection can decrease classifier size and improve accuracy by removing noisy and/or redundant features. However, it is possible for feature selection to yield features that are only partially informative about the classes in the set. These features are beneficial for distinguishing between some classes but not others. In these cases, it is beneficial to divide the large classification problem into a set of smaller problems, where a more specific set of features can be used to classify different classes. Dividing a problem this way is also common when the base classifier is binary, and the problem needs to be reformulated as a set of two-class problems so it can be handled by the classifier. This paper presents a method for multiclass classification that simultaneously formulates a binary tree of simpler classification subproblems and performs feature selection for the individual classifiers. The feature selected hierarchical classifier (FSHC) is tested against several well-known techniques for multiclass division. Tests are run on nine different real data sets and one artificial data set using a support vector machine (SVM) classifier. The results show that the accuracy obtained by the FSHC is comparable with other common multiclass SVM methods. Furthermore, the results demonstrate that the algorithm creates solutions with fewer classifiers, fewer features, and a shorter testing time than the other SVM multiclass extensions. PMID:23757587

Freeman, Cecille; Kuli, Dana; Basir, Otman

2013-12-01

342

Ontology patterns for complex topographic feature yypes  

USGS Publications Warehouse

Complex feature types are defined as integrated relations between basic features for a shared meaning or concept. The shared semantic concept is difficult to define in commonly used geographic information systems (GIS) and remote sensing technologies. The role of spatial relations between complex feature parts was recognized in early GIS literature, but had limited representation in the feature or coverage data models of GIS. Spatial relations are more explicitly specified in semantic technology. In this paper, semantics for topographic feature ontology design patterns (ODP) are developed as data models for the representation of complex features. In the context of topographic processes, component assemblages are supported by resource systems and are found on local landscapes. The topographic ontology is organized across six thematic modules that can account for basic feature types, resource systems, and landscape types. Types of complex feature attributes include location, generative processes and physical description. Node/edge networks model standard spatial relations and relations specific to topographic science to represent complex features. To demonstrate these concepts, data from The National Map of the U. S. Geological Survey was converted and assembled into ODP.

Varanka, Dalia E.

2011-01-01

343

Phenotypic Characterization of miR-92a?/? Mice Reveals an Important Function of miR-92a in Skeletal Development  

PubMed Central

MicroRNAs (miRNAs, miRs) emerged as key regulators of gene expression. Germline hemizygous deletion of the gene that encodes the miR-17?92 miRNA cluster was associated with microcephaly, short stature and digital abnormalities in humans. Mice deficient for the miR-17?92 cluster phenocopy several features such as growth and skeletal development defects and exhibit impaired B cell development. However, the individual contribution of miR-17?92 cluster members to this phenotype is unknown. Here we show that germline deletion of miR-92a in mice is not affecting heart development and does not reduce circulating or bone marrow-derived hematopoietic cells, but induces skeletal defects. MiR-92a?/? mice are born at a reduced Mendelian ratio, but surviving mice are viable and fertile. However, body weight of miR-92a?/? mice was reduced during embryonic and postnatal development and adulthood. A significantly reduced body and skull length was observed in miR-92a?/? mice compared to wild type littermates. µCT analysis revealed that the length of the 5th mesophalanx to 5th metacarpal bone of the forelimbs was significantly reduced, but bones of the hindlimbs were not altered. Bone density was not affected. These findings demonstrate that deletion of miR-92a is sufficient to induce a developmental skeletal defect.

Penzkofer, Daniela; Bonauer, Angelika; Fischer, Ariane; Tups, Alexander; Brandes, Ralf P.; Zeiher, Andreas M.; Dimmeler, Stefanie

2014-01-01

344

CBFS: High Performance Feature Selection Algorithm Based on Feature Clearness  

Microsoft Academic Search

BackgroundThe goal of feature selection is to select useful features and simultaneously exclude garbage features from a given dataset for classification purposes. This is expected to bring reduction of processing time and improvement of classification accuracy.MethodologyIn this study, we devised a new feature selection algorithm (CBFS) based on clearness of features. Feature clearness expresses separability among classes in a feature.

Minseok Seo; Sejong Oh

2012-01-01

345

Anomalous high native resistance to athymic mice to bacterial pathogens.  

PubMed Central

Congenitally athymic (nude) mice exhibited an anomalous high resistance against infections with the facultative intracellular parasite Listeria monocytogenes and other bacterial pathogens. Protection against lethal infection was demonstrated to result from the presence of naturally occurring activated macrophages in the reticuloendothelial organs of the nude mice. This was exemplified after intravenous challenge by enhanced bacterial clearance from the blood and augmented bacterial killing in the spleens and livers of nude mice as compared with immunologically competent control mice. Resident peritoneal macrophages of nude mice were not activated in terms of phagocytic, bactericidal, or tumoricidal potential. The development of activated fixed tissue macrophages appears to arise as a result of the T-lymphocyte deficiency since thymus implantation abrogated the enhanced resistance of nude mice. Antibiotic elimination of intestinal bacteria also modified resistance to bacterial infection, indicating a role of environmental factors on macrophage activation. Several possible mechanisms leading to macrophage activation and heightened resistance to infection in nude mice are offered.

Nickol, A D; Bonventre, P F

1977-01-01

346

Bone phenotypes of P2 receptor knockout mice.  

PubMed

The action of extracellular nucleotides is mediated by ionotropic P2X receptors and G-protein coupled P2Y receptors. The human genome contains 7 P2X and 8 P2Y receptor genes. Knockout mice strains are available for most of them. As their phenotypic analysis is progressing, bone abnormalities have been observed in an impressive number of these mice: distinct abnormalities in P2X7-/- mice, depending on the gene targeting construct and the genetic background, decreased bone mass in P2Y1-/- mice, increased bone mass in P2Y2-/- mice, decreased bone resorption in P2Y6-/- mice, decreased bone formation and bone resorption in P2Y13-/- mice. These findings demonstrate the unexpected importance of extracellular nucleotide signalling in the regulation of bone metabolism via multiple P2 receptors and distinct mechanisms involving both osteoblasts and osteoclasts. PMID:21622253

Orriss, Isabel; Syberg, Susanne; Wang, Ning; Robaye, Bernard; Gartland, Alison; Jorgensen, Niklas; Arnett, Tim; Boeynaems, Jean-Marie

2011-01-01

347

Features in visual search combine linearly.  

PubMed

Single features such as line orientation and length are known to guide visual search, but relatively little is known about how multiple features combine in search. To address this question, we investigated how search for targets differing in multiple features (intensity, length, orientation) from the distracters is related to searches for targets differing in each of the individual features. We tested race models (based on reaction times) and co-activation models (based on reciprocal of reaction times) for their ability to predict multiple feature searches. Multiple feature searches were best accounted for by a co-activation model in which feature information combined linearly (r = 0.95). This result agrees with the classic finding that these features are separable i.e., subjective dissimilarity ratings sum linearly. We then replicated the classical finding that the length and width of a rectangle are integral features-in other words, they combine nonlinearly in visual search. However, to our surprise, upon including aspect ratio as an additional feature, length and width combined linearly and this model outperformed all other models. Thus, length and width of a rectangle became separable when considered together with aspect ratio. This finding predicts that searches involving shapes with identical aspect ratio should be more difficult than searches where shapes differ in aspect ratio. We confirmed this prediction on a variety of shapes. We conclude that features in visual search co-activate linearly and demonstrate for the first time that aspect ratio is a novel feature that guides visual search. PMID:24715328

Pramod, R T; Arun, S P

2014-01-01

348

Escalator design features evaluation  

NASA Technical Reports Server (NTRS)

Escalators are available with design features such as dual speed (90 and 120 fpm), mat operation and flat steps. These design features were evaluated based on the impact of each on capital and operating costs, traffic flow, and safety. A human factors engineering model was developed to analyze the need for flat steps at various speeds. Mat operation of escalators was found to be cost effective in terms of energy savings. Dual speed operation of escalators with the higher speed used during peak hours allows for efficient operation. A minimum number of flat steps required as a function of escalator speed was developed to ensure safety for the elderly.

Zimmerman, W. F.; Deshpande, G. K.

1982-01-01

349

ACR-1000 Passive Features  

SciTech Connect

The Advanced CANDU Reactor{sup TM} (ACR{sup TM}) is a Generation III+ pressure tube type reactor using light water coolant and heavy water moderator. The ACR-1000 reactor design is an evolutionary extension of the proven CANDU reactor design. The ACR-1000 incorporates multiple and diverse passive systems for accident mitigation. Where necessary, one or more features that are passive in nature have been included for mitigation of any postulated accident event. This paper describes how the use of passive design elements complements active features enhances reliability and improves safety margins. (authors)

Lekakh, Boris; Hau, Ken; Ford, Steven [Atomic Energy of Canada Ltd. (Canada)

2006-07-01

350

Mathematical modeling of left ventricular dimensional changes in mice during aging  

PubMed Central

Cardiac aging is characterized by diastolic dysfunction of the left ventricle (LV), which is due in part to increased LV wall stiffness. In the diastolic phase, myocytes are relaxed and extracellular matrix (ECM) is a critical determinant to the changes of LV wall stiffness. To evaluate the effects of ECM composition on cardiac aging, we developed a mathematical model to predict LV dimension and wall stiffness changes in aging mice by integrating mechanical laws and our experimental results. We measured LV dimension, wall thickness, LV mass, and collagen content for wild type (WT) C57/BL6J mice of ages ranging from 7.3 months to those of 34.0 months. The model was established using the thick wall theory and stretch-induced tissue growth to an isotropic and homogeneous elastic composite with mixed constituents. The initial conditions of the simulation were set based on the data from the young mice. Matlab simulations of this mathematical model demonstrated that the model captured the major features of LV remodeling with age and closely approximated experimental results. Specifically, the temporal progression of the LV interior and exterior dimensions demonstrated the same trend and order-of-magnitude change as our experimental results. In conclusion, we present here a validated mathematical model of cardiac aging that applies the thick-wall theory and stretch-induced tissue growth to LV remodeling with age.

2012-01-01

351

A Cyclosporine-Sensitive Psoriasis-Like Disease Produced in Tie2 Transgenic Mice  

PubMed Central

Psoriasis is a common, persistent skin disorder characterized by recurrent erythematous lesions thought to arise as a result of inflammatory cell infiltration and activation of keratinocyte proliferation. Unscheduled angiogenic growth has also been proposed to mediate the pathogenesis of psoriasis although the cellular and molecular basis for this response remains unclear. Recently, a role for the angiopoietin signaling system in psoriasis has been suggested by studies that demonstrate an up-regulation of the tyrosine kinase receptor Tie2 (also known as Tek) as well as angiopoietin-1 and angiopoietin-2 in human psoriatic lesions. To examine temporal expression of Tie2, we have developed a binary transgenic approach whereby expression of Tie2 can be conditionally regulated by the presence of tetracycline analogs in double-transgenic mice. A psoriasis-like phenotype developed in double-transgenic animals within 5 days of birth and persisted throughout adulthood. The skin of affected mice exhibited many cardinal features of human psoriasis including epidermal hyperplasia, inflammatory cell accumulation, and altered dermal angiogenesis. These skin abnormalities resolved completely with tetracycline-mediated suppression of transgene expression, thereby illustrating a complete dependence on Tie2 signaling for disease maintenance and progression. Furthermore, the skin lesions in double-transgenic mice markedly improved after administration of the immunosuppressive anti-psoriatic agent cyclosporine, thus demonstrating the clinical significance of this new model.

Voskas, Daniel; Jones, Nina; Van Slyke, Paul; Sturk, Celina; Chang, Wing; Haninec, Alex; Babichev, Yael Olya; Tran, Jennifer; Master, Zubin; Chen, Stephen; Ward, Nicole; Cruz, Maribelle; Jones, Jamie; Kerbel, Robert S.; Jothy, Serge; Dagnino, Lina; Arbiser, Jack; Klement, Giannoula; Dumont, Daniel J.

2005-01-01

352

A toxicogenomic approach for the prediction of murine hepatocarcinogenesis using ensemble feature selection.  

PubMed

The current strategy for identifying the carcinogenicity of drugs involves the 2-year bioassay in male and female rats and mice. As this assay is cost-intensive and time-consuming there is a high interest in developing approaches for the screening and prioritization of drug candidates in preclinical safety evaluations. Predictive models based on toxicogenomics investigations after short-term exposure have shown their potential for assessing the carcinogenic risk. In this study, we investigated a novel method for the evaluation of toxicogenomics data based on ensemble feature selection in conjunction with bootstrapping for the purpose to derive reproducible and characteristic multi-gene signatures. This method was evaluated on a microarray dataset containing global gene expression data from liver samples of both male and female mice. The dataset was generated by the IMI MARCAR consortium and included gene expression profiles of genotoxic and nongenotoxic hepatocarcinogens obtained after treatment of CD-1 mice for 3 or 14 days. We developed predictive models based on gene expression data of both sexes and the models were employed for predicting the carcinogenic class of diverse compounds. Comparing the predictivity of our multi-gene signatures against signatures from literature, we demonstrated that by incorporating our gene sets as features slightly higher accuracy is on average achieved by a representative set of state-of-the art supervised learning methods. The constructed models were also used for the classification of Cyproterone acetate (CPA), Wy-14643 (WY) and Thioacetamid (TAA), whose primary mechanism of carcinogenicity is controversially discussed. Based on the extracted mouse liver gene expression patterns, CPA would be predicted as a nongenotoxic compound. In contrast, both WY and TAA would be classified as genotoxic mouse hepatocarcinogens. PMID:24040119

Eichner, Johannes; Kossler, Nadine; Wrzodek, Clemens; Kalkuhl, Arno; Bach Toft, Dorthe; Ostenfeldt, Nina; Richard, Virgile; Zell, Andreas

2013-01-01

353

School Community Service Programs: Essential Features for Success  

Microsoft Academic Search

Although much has been written about its benefits, the relationship between community service programs and valued future outcomes has not been uniformly demonstrated. Based on a multinational literature review and key informant interviews, this article identifies 20 program features that are related to positive outcomes. Despite the fact that we are unable to pinpoint which feature or combination of features

Agnes Meinhard; Steven Brown

2010-01-01

354

Demonstration Description for the JLENS OmniEye Demonstration.  

National Technical Information Service (NTIS)

This document contains the demonstration description for the JLENS omniEye demonstration conducted as part of SMDC Media Day on 1-2 May 2000. The purpose of the demonstration is to determine the feasibility of using the OmniEye camera technology on the JL...

G. N. Mayes

2000-01-01

355

Imaging features of adenomyosis  

Microsoft Academic Search

This review focuses on non-invasive imaging techniques that have proven useful in diagnosing adenomyosis, including hysterosalpingography, tran- sabdominal and endovaginal ultrasound, as well as magnetic resonance imaging. An understanding of the histopathological features of this disease is crucial when attempting to interpret the associated imaging findings. The muscular hyperplasia accompanying the heterotopic endometrial tissue actually produces the typical gross appearance

Caroline Reinhold; Faranak Tafazoli; Lin Wang

1998-01-01

356

Sessions Featuring NCI Staff  

Cancer.gov

Sessions Featuring NCI Staff During ASCO’s 2014 Annual Meeting there are different session types in which NCI staff will speak. To see the NCI at ASCO schedule click here: Friday, May 30, 2014 Saturday, May 31, 2014 Sunday, June 1, 2014 Monday, June

357

Basosquamous Carcinoma: Histopathological Features  

PubMed Central

Basosquamous carcinoma (BSC) is a rare aggressive epithelial neoplasm with features of both basal cell carcinoma and squamous cell carcinoma, with a tendency toward local recurrence and a propensity for lymph node and distant metastases. The aim of the present study was to report the case of a 63-year-old Caucasian male with BSC in the auricular region.

Lima, Nadia Lages; Verli, Flaviana Dornela; de Miranda, Joao Luiz; Marinho, Sandra Aparecida

2012-01-01

358

Integrated Education. Feature Issue.  

ERIC Educational Resources Information Center

This "feature issue" provides various perspectives on a number of integrated education topics, including successful integration practices and strategies, the changing roles of teachers, the appropriate role of research, the history and future of integrated education, and the realization of dreams of life in the mainstream for children with severe…

York, Jennifer, Ed.; Vandercook, Terri, Ed.

1988-01-01

359

Searchable solar feature catalogues  

NASA Astrophysics Data System (ADS)

The searchable Solar Feature Catalogues (SFCs) are developed from digitized solar images using automated pattern recognition techniques. The techniques were applied for the detection of sunspots, active regions, filaments and line-of-sight magnetic neutral lines in automatically standardized full disk solar images in Ca II K1, Ca II K3 and Ha lines taken at the Paris-Meudon Observatory and white light images and magnetograms from SOHO/MDI. The results of the automated recognition were verified with manual synoptic maps and available statistical data that revealed good detection accuracy. Based on the recognized parameters, a structured database of Solar Feature Catalogues was built on a MySQL server for every feature and published with various pre-designed search pages on the Bradford University web site http://www.cyber.brad.ac.uk/egso/SFC/. The SFCs with nine year coverage (1996-2004) is to be used for deeper investigation of the feature classification and solar activity forecast.

Zharkova, V. V.; Aboudarham, J.; Zharkov, S.; Ipson, S. S.; Benkhalil, A. K.; Fuller, N.

360

Radiological and Imaging Features  

Microsoft Academic Search

Imaging offers several modalities in the assessment of pediatric inflammatory bowel disease. Thesemodalities are represented by conventional barium studies, sonography and cross-sectional imaging methods such as computed tomography (CT) and magnetic resonance imaging (MRI). We brieflyreview the technical features of these techniques and our findings in cases with pediatric Crohn’sdisease, ulcerative colitis and indeterminate colitis. Choice of the appropriate imaging

Andrea Laghi; Pasquale Paolantonio; Marco Rengo; Federica Vasselli; Veronica Di Mizio; Roberto Di Mizio

2009-01-01

361

Transition. Feature Issue.  

ERIC Educational Resources Information Center

This feature issue of a quarterly bulletin on community integration addresses the topic of transition services for preparing youth with disabilities for adult community living. It contains articles with the following titles and authors: "Transition: The Next Five Years" (David R. Johnson and others); "Transition Policy in the 1990s: Promoting…

Wallace, Teri, Ed.; And Others

1992-01-01

362

Mark Rothko Web Feature  

NSDL National Science Digital Library

Not a virtual exhibition, the Mark Rothko Web Feature by the National Gallery of Art is really a reference work, providing context and background information on the artist. The Web Feature was produced in conjunction with the exhibition, Mark Rothko, at the National Gallery from May 3 through August 16, 1998, now travelling to the Whitney Museum of American Art, September 17-November 29, 1998. The resemblance to a reference book is enhanced by the design of the site, which encourages visitors to page through images of over 30 paintings in chronological order. The Gallery has divided Rothko's career into five periods, and a highlighted navigational bar shows visitors where they are in the chronology. Rothko's explanations of the philosophies behind his work and photographs of the artist help to place the work in context. The actual application of the paint on the canvas is important in Rothko's work, as in that of other abstract expressionists, and some of this nuance is not visible in the Web Feature. In fact, three paintings reproduced as flat black squares, but it is doubtful that these pictures would reproduce any better in the type of art reference book the Web Feature emulates.

363

Feature Dynamic Bayesian Networks  

Microsoft Academic Search

Feature Markov Decision Processes ( MDPs) (Hut09) are well-suited for learning agents in gen- eral environments. Nevertheless, unstructured ( )MDPs are limited to relatively simple environ- ments. Structured MDPs like Dynamic Bayesian Networks (DBNs) are used for large-scale real- world problems. In this article I extend MDP to DBN. The primary contribution is to derive a cost criterion that allows

Marcus Hutter

2008-01-01

364

Feature Level Sensor Fusion.  

National Technical Information Service (NTIS)

This paper describes two practical fusion techniques (hybrid fusion and cued fusion) for automatic target cueing that combine features derived from each sensor data at the object-level. In the hybrid fusion method each of the input sensor data is prescree...

T. Peli M. Young R. Knox K. Ellis F. Bennett

1999-01-01

365

Feature Selection for Unsupervised Learning  

Microsoft Academic Search

In this paper, we identify two issues involved in developing an automated feature subset selection algorithm for unlabeled data: the need for finding the number of clusters in conjunction with feature selection, and the need for normalizing the bias of feature selection criteria with respect to dimension. We explore the feature selection problem and these issues through FSSEM (Feature Subset

Jennifer G. Dy; Carla E. Brodley

2004-01-01

366

Streaming Feature Selection using IIC  

Microsoft Academic Search

In Streaming Feature Selection (SFS), new fea- tures are sequentially considered for addition to a predictive model. When the space of poten- tial features is large, SFS offers many advantages over methods in which all features are assumed to be known in advance. Features can be generated dynamically, focusing the search for new features on promising subspaces, and overfitting can

Lyle H. Ungar; Jing Zhou; Dean P. Foster; Bob A. Stine

2005-01-01

367

A Dramatic Flame Test Demonstration.  

ERIC Educational Resources Information Center

Flame tests are used for demonstration of atomic structure. Describes a demonstration that uses spray bottles filled with methanol and a variety of salts to produce a brilliantly colored flame. (Contains 11 references.) (ASK)

Johnson, Kristin A.; Schreiner, Rodney

2001-01-01

368

Revisiting the Electric Pickle Demonstration  

ERIC Educational Resources Information Center

The electric pickle is a classic demonstration that is widely used in both high school and college settings to explain the general principles behind atomic emission. The demonstration fails to provide an interesting multi-line spectrum.

Journal of Chemical Education, 2005

2005-01-01

369

Alaska Propylene Glycol Field Demonstration.  

National Technical Information Service (NTIS)

The use of propylene glycol (PG) base antifreeze in military vehicles is being evaluated. Following a successful field demonstration of a formulated Propylene Glycol Antifreese (PGAF) at Ft. Bliss TX, a follow on demonstration was conducted at Ft. Wainwri...

D. Davis

1997-01-01

370

Feature-feature causal relations and statistical co-occurrences in object concepts  

PubMed Central

Influences of feature-feature statistical co-occurrences and causal relations have been found in some circumstances, but not others. We hypothesized that detecting an influence of these knowledge types hinges crucially on the congruence between the task and type of knowledge. We show that both knowledge types influence tasks that tap feature relatedness. Detailed descriptions of causal theories were collected, and co-occurrence statistics were based on feature production norms. Regression analyses tested the influences of these knowledge types in untimed relatedness ratings and speeded relatedness decisions for 65 feature pairs spanning a range of correlational strength. Both knowledge types influenced both tasks, demonstrating that causal theories and statistical co-occurrences between features influence conceptual computations.

McNorgan, Chris; Kotack, Rachel A.; Meehan, Deborah C.; McRae, Ken

2011-01-01

371

?-Arrestin-1 Deficiency Protects Mice from Experimental Colitis  

PubMed Central

?-Arrestins are intracellular scaffolding proteins that modulate specific cell signaling pathways. Recent studies, in both cell culture and in vivo models, have demonstrated an important role for ?-arrestin-1 in inflammation. However, the role of ?-arrestin-1 in the pathogenesis of inflammatory bowel disease (IBD) is not known. Our goal was to investigate the role of ?-arrestin-1 in IBD using mouse models of colitis. To this end, we subjected wild-type (WT) and ?-arrestin-1 knockout (?-arr-1?/?) mice to colitis induced by trinitrobenzenesulfonic acid or dextran sulfate sodium and examined the clinical signs, gross pathology, and histopathology of the colon, as well as inflammatory components. The ?-arr-1?/? mice displayed significantly attenuated colitis, compared with WT mice, in both models. Consistent with the phenotypic observations, histological examination of the colon revealed attenuated disease pathology in the ?-arr-1?/? mice. Our results further demonstrate that ?-arr-1?/? mice are deficient in IL-6 expression in the colon, but have higher expression of the anti-inflammatory IL-10 family of cytokines. Our results also demonstrate diminished ERK and NF?B pathways in the colons of ?-arr-1?/? mice, compared with WT mice. Taken together, our results demonstrate that decreased IL-6 production and enhanced IL-10 and IL-22 production in ?-arrestin-1–deficient mice likely lead to attenuated gut inflammation.

Lee, Taehyung; Lee, Eunhee; Irwin, Regina; Lucas, Peter C.; McCabe, Laura R.; Parameswaran, Narayanan

2014-01-01

372

Favorite Demonstrations for College Science  

ERIC Educational Resources Information Center

Peer-reviewed, classroom-tested, and tailored specifically for introductory science courses, Favorite Demonstrations is a complement to every college instructor's lesson plans. The book is an all-in-one compilation of 36 popular classroom demonstrations published since 1993 in the "Favorite Demonstration" column of NSTA's Journal of College …

Shmaefsky, Brian

2004-01-01

373

Female Mecp2+/? mice display robust behavioral deficits on two different genetic backgrounds providing a framework for pre-clinical studies  

PubMed Central

Rett syndrome (RTT) is an X-linked neurological disorder caused by mutations in the gene encoding the transcriptional modulator methyl-CpG-binding protein 2 (MeCP2). Typical RTT primarily affects girls and is characterized by a brief period of apparently normal development followed by the loss of purposeful hand skills and language, the onset of anxiety, hand stereotypies, autistic features, seizures and autonomic dysfunction. Mecp2 mouse models have extensively been studied to demonstrate the functional link between MeCP2 dysfunction and RTT pathogenesis. However, the majority of studies have focused primarily on the molecular and behavioral consequences of the complete absence of MeCP2 in male mice. Studies of female Mecp2+/? mice have been limited because of potential phenotypic variability due to X chromosome inactivation effects. To determine whether reproducible and reliable phenotypes can be detected Mecp2+/? mice, we analyzed Mecp2+/? mice of two different F1 hybrid isogenic backgrounds and at young and old ages using several neurobehavioral and physiological assays. Here, we report a multitude of phenotypes in female Mecp2+/? mice, some presenting as early as 5 weeks of life. We demonstrate that Mecp2+/? mice recapitulate several aspects of typical RTT and show that mosaic expression of MeCP2 does not preclude the use of female mice in behavioral and molecular studies. Importantly, we uncover several behavioral abnormalities that are present in two genetic backgrounds and report on phenotypes that are unique to one background. These findings provide a framework for pre-clinical studies aimed at improving the constellation of phenotypes in a mouse model of RTT.

Samaco, Rodney C.; McGraw, Christopher M.; Ward, Christopher S.; Sun, Yaling; Neul, Jeffrey L.; Zoghbi, Huda Y.

2013-01-01

374

NEW FEATURES FOR MCNPX  

SciTech Connect

Many of the features and options recently developed for and tested in LAHETS have been implemented for the next release of MCNPX. The most significant of these are: defined elastic scattering and reaction cross sections for incident particles at all energies in the absence of cross section libraries; attenuated primary beam transport without nonelastic interaction; a new atomic mass data base and the code to access it for all the physics packages shared by LAHET and MCNPX; a new nuclear structure/decay data library and the coding necessary to provide estimation of metastable state production; and the cross section calculation option adapted from LAHETL4, with output processed by the XSEXS code. Of these features, the first has the greatest impact on calculations with MCNPX.

R. E. PRAEL; H. G.HUGHES; W. B. WILSON; S. MASHNIK

2000-09-01

375

CBFS: High Performance Feature Selection Algorithm Based on Feature Clearness  

PubMed Central

Background The goal of feature selection is to select useful features and simultaneously exclude garbage features from a given dataset for classification purposes. This is expected to bring reduction of processing time and improvement of classification accuracy. Methodology In this study, we devised a new feature selection algorithm (CBFS) based on clearness of features. Feature clearness expresses separability among classes in a feature. Highly clear features contribute towards obtaining high classification accuracy. CScore is a measure to score clearness of each feature and is based on clustered samples to centroid of classes in a feature. We also suggest combining CBFS and other algorithms to improve classification accuracy. Conclusions/Significance From the experiment we confirm that CBFS is more excellent than up-to-date feature selection algorithms including FeaLect. CBFS can be applied to microarray gene selection, text categorization, and image classification.

Seo, Minseok; Oh, Sejong

2012-01-01

376

Vector features for image matching and image registration  

NASA Astrophysics Data System (ADS)

Image matching plays an important role in a variety of applications. For matching images, the features are needed to describe the local content of images. In this paper, we proposed novel features (Vector Features) for image matching and image registration. The vector features are based on the intensity differences of the pixels around the interesting points and characterize the spatial distribution of gray values in an effective and efficient way. In the experiments, the invariance of vector features to image rotation is verified. The vector features perform well on the images of different focal lengths and the multi-view images. The experiment on image registration demonstrates a good result.

Liang, Jianning; Zhou, Yan

2014-01-01

377

Coloring Local Feature Extraction  

Microsoft Academic Search

\\u000a Although color is commonly experienced as an indispensable quality in describing the world around us, state-of-the art local feature-based representations are mostly based on shape description, and ignore color information. The description of color\\u000a is hampered by the large amount of variations which causes the measured color values to vary significantly. In this paper\\u000a we aim to extend the description

Joost Van De Weijer; Cordelia Schmid

2006-01-01

378

DCTD — Featured Agents  

Cancer.gov

The “Featured Agents” portion of the DCTD Website provides information for researchers involved in drug discovery and development. Any public preclinical and clinical data that DCTD has on a particular agent are presented here. New agents will be added periodically to the current list. DCTD Website visitors may subscribe to the Listserv on this page to be notified when additions to the list are made.

379

Bayesian Feature Construction  

Microsoft Academic Search

\\u000a The present paper discusses the issue of enhancing classification performance by means other than improving the ability of\\u000a certain Machine Learning algorithms to construct a precise classification model. On the contrary, we approach this significant\\u000a problem from the scope of an extended coding of training data. More specifically, our method attempts to generate more features\\u000a in order to reveal the

Manolis Maragoudakis; Nikos Fakotakis

2006-01-01

380

AMS Featured Reviews  

NSDL National Science Digital Library

The American Mathematical Society's MathSciNet now presents Featured Reviews from Mathematical Reviews online. "Since its founding in 1940, Mathematical Reviews (MR) has aimed to serve researchers and scholars in the mathematical sciences by providing timely information on articles and books that contain new contributions to mathematical research," state the editors. The purpose of the Featured Reviews page is to assist researchers in accessing the most outstanding reviews without having to wade through the thousands of reviews that are posted to MR online each month. The editors state that the Featured Reviews "...will cover some of the very best papers published in mathematics, identified by the MR editors with the advice of distinguished outside mathematicians as being especially important in one or more of the areas covered by MR. The reviewers for these papers are asked to set the paper in context, perhaps with some historical background, state the main results of the paper, outline (in not too technical a fashion) the main new ideas in the paper and include their evaluation of the paper." Each four- to six-paragraph-long review, available in HTML, .dvi, .ps, or .pdf format, gives the reviewer's name and the full article citation, hyperlinked when possible. This should prove to be a valuable Web resource for academic mathematicians.

2001-01-01

381

Spontaneous arthritis and ankylosis in male DBA/1 mice: further evidence for a role of behavioral factors in "stress-induced arthritis"  

PubMed Central

Background Ageing male DBA/1 mice spontaneously develop arthritis in the hind paws. We and others have demonstrated that this model shares striking features with human spondyloarthritis, in particular entheseal involvement, progressive ankylosis but also dactylitis. Here, we report on our recent experience with this model highlighting how changes in the animal facility affect the development of the disease. Findings Ageing male DBA/1 mice from different litters were caged together (6 mice per cage) at the age of 10 weeks. The mice were checked twice a week for clinical signs of arthritis. Disease severity was assessed in further detail post-mortem by scoring for histomorphological characteristics. DBA/1 mice spontaneously develop macroscopically detectable arthritis, presenting as joint swelling or toe stiffness. Standard settings with open cages lead to an almost 100% incidence by the age of 26 weeks. The introduction of larger cages and filter tops reducing exposure to other cages dramatically affected incidence. Other negative factors include excess bedding material reducing the impact of walking and running. Switching back to the original conditions resulted again in a high incidence, further optimized by sensory exposure to female mice. We also showed that the related DBA/2 strain is sensitive to the disease. Conclusions Changing environmental factors in the housing conditions of DBA/1 mice severely affects the spontaneous development of arthritis. This points out that the model is very sensitive to external stress and sensory factors that are likely affecting the behavior of the male mice and that the model needs to be optimized in different situations.

2012-01-01

382

Characterization of a New Model of Thromboembolic Stroke in C57 black/6J mice.  

PubMed

This study characterizes a new model of thromboembolic stroke of the middle cerebral artery in C57 black/6J mice, thus offering an opportunity to use the model for studying ischemic stroke in transgenic mice. Thromboembolic stroke was induced by local injection of either 1.5 or 3.0 UI of thrombin directly into the right MCA of C57 black/6J mice. Cerebral blood flow (CBF) velocity was measured continuously by laser Doppler flowmetry, which allowed documentation of both MCA occlusion and of spontaneous recanalization. After 24 h, all animals were euthanized. Cryosections were cut at 400-?m intervals and silver stained with the high-contrast method for volumetric assessment of infarct size. Interleukin (IL)-6, tumor necrosis factor-alpha (TNF-?), caspase-3 and hsp 70 protein levels were investigated by immunofluorescence. Thrombin injection resulted in clot formation in all animals. Cortical infarction occurred in 63 % of the mice while 37 % had a spontaneous MCA recanalization during the first 20 min following thrombin injection. In cases of successful MCA occlusion with consequent infarction, the clot was stable up to 2 h after formation. Subsequently, 20 % recanalized spontaneously. Infarctions were restricted to the cortex with a mean lesion volume of 36?±?5 for 1.5 UI and 56?±?8 for 3.0 UI thrombin. Protein levels of IL-6, TNF-?, caspase-3, and hsp 70 were significantly increased after MCAO. The results demonstrate that the mouse thromboembolic stroke model produces cortical infarctions of consistent size in C57 black/6J mice, which is dependent upon the amount of thrombin used for clot formation. Spontaneous MCA recanalization occurs after 2 h of ischemia in 20 % of mice. Thus, the thromboembolic model is an applicable stroke model for C57 black/6J mice, which mimics many of the features of human stroke, including spontaneous recanalization. However, strain differences between Swiss and C57 black/6J mice must be taken into account when using the model. PMID:24347404

Ansar, Saema; Chatzikonstantinou, Eva; Wistuba-Schier, Anja; Mirau-Weber, Silvia; Fatar, Marc; Hennerici, Michael G; Meairs, Stephen

2014-08-01

383

MMIC Phased Array Demonstrations with ACTS  

NASA Technical Reports Server (NTRS)

Over a one year period from May 1994 to May 1995, a number of demonstrations were conducted by the NASA Lewis Research Center (LeRC) in which voice, data, and/or video links were established via NASA's advanced communications technology satellite (ACTS) between the ACTS link evaluation terminal (LET) in Cleveland, OH, and aeronautical and mobile or fixed Earth terminals having monolithic microwave integrated circuit (MMIC) phased array antenna systems. This paper describes four of these. In one, a duplex voice link between an aeronautical terminal on the LeRC Learjet and the ACTS was achieved. Two others demonstrated duplex voice (and in one case video as well) links between the ACTS and an Army vehicle. The fourth demonstrated a high data rate downlink from ACTS to a fixed terminal. Array antenna systems used in these demonstrations were developed by LeRC and featured LeRC and Air Force experimental arrays using gallium arsenide MMIC devices at each radiating element for electronic beam steering and distributed power amplification. The single 30 GHz transmit array was developed by NASA/LeRC and Texas Instruments. The three 20 GHz receive arrays were developed in a cooperative effort with the Air Force Rome Laboratory, taking advantage of existing Air Force array development contracts with Boeing and Lockheed Martin. The paper describes the four proof-of-concept arrays and the array control system. The system configured for each of the demonstrations is described, and results are discussed.

Raquet, Charles A. (Compiler); Martzaklis, Konstantinos (Compiler); Zakrajsek, Robert J. (Compiler); Andro, Monty (Compiler); Turtle, John P.

1996-01-01

384

C/EBP Homologous Protein-induced Macrophage Apoptosis Protects Mice from Steatohepatitis*  

PubMed Central

Nonalcoholic fatty liver disease is a heterogeneous disorder characterized by liver steatosis; inflammation and fibrosis are features of the progressive form nonalcoholic steatohepatitis. The endoplasmic reticulum stress response is postulated to play a role in the pathogenesis of nonalcoholic fatty liver disease and nonalcoholic steatohepatitis. In particular, C/EBP homologous protein (CHOP) is undetectable under normal conditions but is induced by cellular stress, including endoplasmic reticulum stress. Chop wild type (Chop+/+) and knock-out (Chop?/?) mice were used in these studies to elucidate the role of CHOP in the pathogenesis of fatty liver disease. Paradoxically, Chop?/? mice developed greater liver injury, inflammation, and fibrosis than Chop+/+ mice, with greater macrophage activation. Primary, bone marrow-derived, and peritoneal macrophages from Chop+/+ and Chop?/? were challenged with palmitic acid, an abundant saturated free fatty acid in plasma and liver lipids. Where palmitic acid treatment activated Chop+/+ and Chop?/? macrophages, Chop?/? macrophages were resistant to its lipotoxicity. Chop?/? mice were sensitized to liver injury in a second model of dietary steatohepatitis using the methionine-choline-deficient diet. Analysis of bone marrow chimeras between Chop?/? and Chop+/+ mice demonstrated that Chop in macrophages protects from liver injury and inflammation when fed the methionine-choline-deficient diet. We conclude that Chop deletion has a proinflammatory effect in fatty liver injury apparently due to decreased cell death of activated macrophages, resulting in their net accumulation in the liver. Thus, macrophage CHOP plays a key role in protecting the liver from steatohepatitis likely by limiting macrophage survival during lipotoxicity.

Malhi, Harmeet; Kropp, Erin M.; Clavo, Vinna F.; Kobrossi, Christina R.; Han, JaeSeok; Mauer, Amy S.; Yong, Jing; Kaufman, Randal J.

2013-01-01

385

Magnetization transfer contrast imaging reveals amyloid pathology in Alzheimer's disease transgenic mice.  

PubMed

The presence of amyloid plaques in the brain is one of the pathological hallmarks of Alzheimer's disease, which might already be present in the early stage of the disease. Therefore it is important to track amyloid plaques as early as possible. In this paper, we report magnetization transfer contrast magnetic resonance imaging (MTC MRI) as a novel approach to detect amyloid plaques in vivo. Two mice models, APP/PS1 and BRI, developing amyloid pathology were investigated with MTC MRI, T2 relaxation measurements and immunohistochemistry (IHC). MT-ratios of several brain regions were compared to T2-values and correlated with quantitative IHC, revealing amyloid load and gliosis in different brain regions. APP/PS1 mice develop large compact plaques, resembling late stage Alzheimer's disease, while rather small and diffuse plaques are deposited in BRI mice, reflecting early stage of Alzheimer's disease. We found significantly higher MT-ratio's in the brain of APP/PS1 mice as compared to their controls and similar trends in BRI mice. A region based MT-ratio and IHC analysis and correlations between MT-ratios and quantitative IHC indicate amyloid plaques as the main substrate for altered MT-ratios in transgenic animals. We additionally demonstrated the improved sensitivity of MTC MRI to amyloid pathology as compared to traditional T2 relaxation measurements. Our results suggest that MTC MRI reveals extensive, and potentially even early amyloid pathology. Further unraveling the MT-effect of each pathological feature during each stage of AD might indicate MTC MRI as a useful diagnostic technique. PMID:24188815

Bigot, Christian; Vanhoutte, Greetje; Verhoye, Marleen; Van der Linden, Annemie

2014-02-15

386

Feature Subset Selection by Using Sorted Feature Relevance  

Microsoft Academic Search

Real world classification applications usually have many features. This increases the complexity of the classification task. Choosing a subset of the features may increase accuracy and reduce complexity of the acquired knowledge. We present a new feature subset selection method by using sorted feature relevance. We tested the new method on real world and arti- ficial datasets and compared its

Olcay Boz

2002-01-01

387

Progress of the MICE experiment at RAL  

NASA Astrophysics Data System (ADS)

The international Muon Ionization Cooling Experiment (MICE) will perform a systematic investigation of ionization cooling of a muon beam. The demonstration comprises one cell of the US Neutrino Factory Study II cooling channel. Results obtained on the construction of the beamline and its instrumentation (STEP I) will be reviewed, together with progress towards final measurements of ionization cooling (STEP IV and VI).

Bonesini, M.

2013-04-01

388

Favorite Demonstration: Demonstrating an Interactive Genetic Drift Exercise  

NSDL National Science Digital Library

The exercise presented here is a hands-on demonstration of the phenomenon of genetic drift in populations. In particular, it reinforces the random nature of drift and demonstrates the effect that population size can have on the mean frequency of an allele

Carter, Ashley J.

2003-03-01

389

Demonstrations with a Vacuum: Old Demonstrations for New Vacuum Pumps.  

ERIC Educational Resources Information Center

Explains mechanisms of 19th-century vacuum pumps. Describes demonstrations using the pump including guinea and feather tube, aurora tube, electric egg, Gassiots cascade, air mill, bell in vacuum, density and buoyancy of air, fountain in vacuum, mercury shower, palm and bladder glasses, Bacchus demonstration, pneumatic man-lifter, and Magdeburg…

Greenslade, Thomas B., Jr.

1989-01-01

390

Status of MICE, the international Muon Ionization Cooling Experiment  

NASA Astrophysics Data System (ADS)

The Muon Ionization Cooling Experiment (MICE) will demonstrate transverse muon ionization cooling and is thus a strategic R&D project for future muon facilities. It is under development at the Rutherford Appleton Laboratory in the United Kingdom.

Bross, Alan D.; MICE Collaboration

2012-08-01

391

Passive Safety Features for Small Modular Reactors  

SciTech Connect

The rapid growth in the size and complexity of commercial nuclear power plants in the 1970s spawned an interest in smaller, simpler designs that are inherently or intrinsically safe through the use of passive design features. Several designs were developed, but none were ever built, although some of their passive safety features were incorporated into large commercial plant designs that are being planned or built today. In recent years, several reactor vendors are actively redeveloping small modular reactor (SMR) designs with even greater use of passive features. Several designs incorporate the ultimate in passive safety they completely eliminate specific accident initiators from the design. Other design features help to reduce the likelihood of an accident or help to mitigate the accident s consequences, should one occur. While some passive safety features are common to most SMR designs, irrespective of the coolant technology, other features are specific to water, gas, or liquid-metal cooled SMR designs. The extensive use of passive safety features in SMRs promise to make these plants highly robust, protecting both the general public and the owner/investor. Once demonstrated, these plants should allow nuclear power to be used confidently for a broader range of customers and applications than will be possible with large plants alone.

Ingersoll, Daniel T [ORNL] [ORNL

2010-01-01

392

Dissociation of seizure traits in inbred strains of mice using the flurothyl kindling model of epileptogenesis  

Microsoft Academic Search

Previous seizure models have demonstrated genetic differences in generalized seizure threshold (GST) in inbred mice, but the genetic control of epileptogenesis is relatively unexplored. The present study examined, through analysis of inbred strains of mice, whether the seizure characteristics observed in the flurothyl kindling model are under genetic control. Eight consecutive, daily generalized seizures were induced by flurothyl in mice

Dominick Papandrea; Tara M. Anderson; Bruce J. Herron; Russell J. Ferland

2009-01-01

393

Staring naval infrared search and track demonstrator  

NASA Astrophysics Data System (ADS)

A Naval Infrared Search and Track (IRST) demonstrator has been developed for the UK Ministry of Defence. The system uses two staring infrared cameras and split field of view optics to provide panoramic surveillance of the horizon. Use of staring detectors provides improved sensitivity and faster update rate than current scanning IRST systems. The demonstrator is fitted with commercial 640x512 pixel medium waveband detectors but is designed to accommodate 1024x768 pixel detectors in the future. The system features switchable spectral filters to allow choice of the optimum waveband for the prevailing environmental conditions and beam steering optics for non uniformity correction and image stabilisation. Real time processing has been implemented using a combination of Field Programmable Gate Array and PowerPC hardware for detection and tracking. The paper describes the system and presents some examples of its output.

Manson, Don; Richards, Mike; Nicolson, Tim; Khan, Tariq; Barron, Don; Evans, Graham

2005-10-01

394

Features of MCNP6  

NASA Astrophysics Data System (ADS)

MCNP6 is simply and accurately described as the merger of MCNP5 and MCNPX capabilities, but it is much more than the sum of these two computer codes. MCNP6 is the result of six years of effort by the MCNP5 and MCNPX code development teams. These groups of people, residing in Los Alamos National Laboratory's X Computational Physics Division, Monte Carlo Codes Group (XCP-3) and Nuclear Engineering and Nonproliferation Division, Radiation Transport Modeling Team (NEN-5) respectively, have combined their code development efforts to produce the next evolution of MCNP. While maintenance and major bug fixes will continue for MCNP5 1.60 and MCNPX 2.7.0 for upcoming years, new code development capabilities only will be developed and released in MCNP6. In fact, the initial release of MCNP6 contains numerous new features not previously found in either code. These new features are summarized in this document. Packaged with MCNP6 is also the new production release of the ENDF/B-VII.1 nuclear data files usable by MCNP. The high quality of the overall merged code, usefulness of these new features, along with the desire in the user community to start using the merged code, have led us to make the first MCNP6 production release: MCNP6 version 1. High confidence in the MCNP6 code is based on its performance with the verification and validation test suites, comparisons to its predecessor codes, our automated nightly software debugger tests, the underlying high quality nuclear and atomic databases, and significant testing by many beta testers.

Goorley, T.; James, M.; Booth, T.; Brown, F.; Bull, J.; Cox, L. J.; Durkee, J.; Elson, J.; Fensin, M.; Forster, R. A.; Hendricks, J.; Hughes, H. G.; Johns, R.; Kiedrowski, B.; Martz, R.; Mashnik, S.; McKinney, G.; Pelowitz, D.; Prael, R.; Sweezy, J.; Waters, L.; Wilcox, T.; Zukaitis, T.

2014-06-01

395

Saturn's Fascinating Features  

NSDL National Science Digital Library

Children will learn to write with scientific accuracy to characterize Saturn and its features as they create their own multilayer 3-D book of Saturn, with diagrams showing its various layers, ring system and many moons. Includes a glossary, information for families, and guidance for deepening the science. This is lesson 4 of 8 in the Jewel of the Solar System: From Out-of-School to Outer Space, an adaptation for afterschool programs of the Cassini-Huygens educational product Reading, Writing, and Rings.

396

Dehydration parameters and standards for laboratory mice.  

PubMed

Water deprivation and restriction are common features of many physiologic and behavioral studies; however, there are no data-driven humane standards regarding mice on water deprivation or restriction studies to guide IACUC, investigators, and veterinarians. Here we acutely deprived outbred CD1 mice of water for as long as 48 h or restricted them to a 75% or 50% water ration; physical and physiologic indicators of dehydration were measured. With acute water deprivation, the appearance and attitude of mice deteriorated after 24 h, and weight loss exceeded 15%. Plasma osmolality was increased, and plasma volume decreased with each time interval. Plasma corticosterone concentration increased with duration of deprivation. There were no differences in any dehydration measures between mice housed in conventional static cages or ventilated racks. Chronic water restriction induced no significant changes compared with ad libitum availability. We conclude that acute water deprivation of as long as 24 h produces robust physiologic changes; however, deprivation in excess of 24 h is not recommended in light of apparent animal distress. Although clearly thirsty, mice adapt to chronic water restriction of as much as 50% of the ad libitum daily ration that is imposed over an interval of as long as 8 d. PMID:23849404

Bekkevold, Christine M; Robertson, Kimberly L; Reinhard, Mary K; Battles, August H; Rowland, Neil E

2013-01-01

397

Imatinib mesylate ameliorates the dystrophic phenotype in exercised mdx mice  

Microsoft Academic Search

Myofiber degeneration, inflammation, and fibrosis are remarkable features of Duchenne muscular dystrophy. We hypothesized that the administration of imatinib mesylate, an inhibitor of tyrosine kinase and TGF-? pro-fibrogenic activity, could improve the muscular conditions in mdx mice. Four-week old mdx mice were treated and exercised for 6 weeks. Gastrocnemius and diaphragm histopathology, strength, creatine kinase, and cytokine levels were evaluated. The

João Carlos da Silva Bizario; Daniel Giuliano Cerri; Lilian Cataldi Rodrigues; Gislane L. V. Oliveira; Auro Nomizo; Daniela Dover de Araujo; Paula Sakemi Fukuhara; Juliana Caldas Ribeiro; Fabíola Attié de Castro; Maria Cristina Ramos Costa

2009-01-01

398

MICE RF TEST STAND  

Microsoft Academic Search

The Muon Ionisation Cooling Experiment (MICE) RF test stand is being assembled at Daresbury Laboratory. This will provide a test bed for power amplifiers to produce the 2MW 200MHz RF for the MICE experiment RF cavities. Initial design and proposed layout of the RF system are described.

P. A. Corlett; A. Moss; J. Orrett

2006-01-01

399

Action recognition using dynamics features  

Microsoft Academic Search

In this paper, we propose a method of action recognition using dynamics features based on physics model. The dynamics features are composed of torques from knee and hip joints of both legs and implicitly include the gravity, ground reaction forces, and the pose of the remaining body parts. These features are more discriminative than the kinematics features, and they result

Al Mansur; Yasushi Makihara; Yasushi Yagi

2011-01-01

400

Activation of multiple signaling pathways causes developmental defects in mice with a Noonan syndrome-associated Sos1 mutation  

PubMed Central

Noonan syndrome (NS) is an autosomal dominant genetic disorder characterized by short stature, unique facial features, and congenital heart disease. About 10%–15% of individuals with NS have mutations in son of sevenless 1 (SOS1), which encodes a RAS and RAC guanine nucleotide exchange factor (GEF). To understand the role of SOS1 in the pathogenesis of NS, we generated mice with the NS-associated Sos1E846K gain-of-function mutation. Both heterozygous and homozygous mutant mice showed many NS-associated phenotypes, including growth delay, distinctive facial dysmorphia, hematologic abnormalities, and cardiac defects. We found that the Ras/MAPK pathway as well as Rac and Stat3 were activated in the mutant hearts. These data provide in vivo molecular and cellular evidence that Sos1 is a GEF for Rac under physiological conditions and suggest that Rac and Stat3 activation might contribute to NS phenotypes. Furthermore, prenatal administration of a MEK inhibitor ameliorated the embryonic lethality, cardiac defects, and NS features of the homozygous mutant mice, demonstrating that this signaling pathway might represent a promising therapeutic target for NS.

Chen, Peng-Chieh; Wakimoto, Hiroko; Conner, David; Araki, Toshiyuki; Yuan, Tao; Roberts, Amy; Seidman, Christine E.; Bronson, Roderick; Neel, Benjamin G.; Seidman, Jonathan G.; Kucherlapati, Raju

2010-01-01

401

TRUEX hot demonstration. Final report  

Microsoft Academic Search

In FY 1987, a program was initiated to demonstrate technology for recovering transuranic (TRU) elements from defense wastes. This hot demonstration was to be carried out with solution from the dissolution of irradiated fuels. This recovery would be accomplished with both PUREX and TRUEX solvent extraction processes. Work planned for this program included preparation of a shielded-cell facility for the

D. B. Chamberlain; R. A. Leonard; J. C. Hoh; E. C. Gay; D. G. Kalina; G. F. Vandegrift

1990-01-01

402

A Demonstration Handbook for Physics  

NSDL National Science Digital Library

Created as a guide for high school and college physics teachers, this handbook contains hundreds of apparatus demonstrations that require only low-cost, everyday materialsis. These demonstrations can be used for lecture presentations, laboratory exercises, or projects. A valuable resource for any teacher looking to perk up their classroom.

2007-06-22

403

The "Mushroom Cloud" Demonstration Revisited  

ERIC Educational Resources Information Center

A revisitation of the classical "mushroom cloud" demonstration is described. Instead of aniline and benzoyl peroxide, the proposed reaction involves household chemicals such as alpha-pinene (turpentine oil) and trichloroisocyanuric acid ("Trichlor") giving an impressive demonstration of oxidation and combustion reactions that…

Panzarasa, Guido; Sparnacci, Katia

2013-01-01

404

A Comprehensive General Chemistry Demonstration  

ERIC Educational Resources Information Center

This article describes the use of a comprehensive demonstration suitable for a high school or first-year undergraduate introductory chemistry class. The demonstration involves placing a burning candle in a container adjacent to a beaker containing a basic solution with indicator. After adding a lid, the candle will extinguish and the produced…

Sweeder, Ryan D.; Jeffery, Kathleen A.

2013-01-01

405

Three Mechanical Demonstrations of Chaos.  

ERIC Educational Resources Information Center

Describes three demonstrations showing chaotic motion, which makes long-term prediction impossible. Discusses the apparatus for the demonstrations and procedures for illustrating chaotic motion of pendulum, balls rolling in a double potential well, and a ball rolling on a balanced beam. (YP)

Ehrlich, Robert

1990-01-01

406

Understanding Statistics Using Computer Demonstrations  

ERIC Educational Resources Information Center

This paper discusses programs that clarify some statistical ideas often discussed yet poorly understood by students. The programs adopt the approach of demonstrating what is happening, rather than using the computer to do the work for the students (and hide the understanding). The programs demonstrate normal probability plots, overfitting of…

Dunn, Peter K.

2004-01-01

407

Rocket Ignition Demonstrations Using Silane  

NASA Technical Reports Server (NTRS)

Rocket ignition demonstration tests using silane were performed at the Penn State Combustion Research Laboratory. A heat sink combustor with one injection element was used with gaseous propellants. Mixtures of silane and hydrogen were used as fuel, and oxygen was used as oxidizer. Reliable ignition was demonstrated using fuel lead and and a swirl injection element.

Pal, Sibtosh; Santoro, Robert; Watkins, William B.; Kincaid, Kevin

1998-01-01

408

A Demonstration of Sample Segregation  

ERIC Educational Resources Information Center

The demonstration of sample segregation, which is simple, and visually compelling illustrates the importance of sample handling for students studying analytical chemistry and environmental chemistry. The mixture used in this demonstration has two components, which have big particle size, and different colors, which makes the segregation graphic.

Fritz, Mark D.; Brumbach, Stephen B.; Hartman, JudithAnn R.

2005-01-01

409

Demonstrating Allotropic Modifications of Sulfur.  

ERIC Educational Resources Information Center

Shows how a common demonstration that consists of slowly heating sulfur powder in a test tube to illustrate sulfur's allotropic modifications can convince students of conclusions about the moon Io which they often find surprising. Describes the demonstration in full. (Author/MM)

McCarty, Jillian L.; Dragojlovic, Veljko

2002-01-01

410

A Demonstration on Every Exam.  

ERIC Educational Resources Information Center

Argues that inclusion of demonstrations on examinations increases students' ability to observe carefully the physical world around them, translate from observation in terms of models, and make quantitative estimates and physicist-type "back-of-the-envelope" calculations. Presents demonstration ideas covering the following topics: mechanics,…

Julian, Glenn M.

1995-01-01

411

Favorite Demonstration: Demonstrating Emergent Properties in Dynamic Systems  

NSDL National Science Digital Library

This demonstration was developed for an introduction to a soil science class to show how emergent properties are an essential behavior endemic to dynamic systems; explanations for their existence are not dependent on external forces. Emergent properties a

Fink, Douglas S.

2009-09-01

412

Tested Demonstrations: A Simple Demonstration of Reversible Oxygenation.  

ERIC Educational Resources Information Center

Materials needed, reaction involved, and potential hazards are provided for a demonstration of reversible oxygenation. Also discusses the importance of the reaction in biological systems, focusing on hemoglobin/myoglobin and their function in mammals. (JM)

Kildahl, Nicholas K.

1983-01-01

413

Altered Tnnt3 characterizes selective weakness of fast fibers in mice overexpressing FSHD region gene 1 (FRG1).  

PubMed

Facioscapulohumeral muscular dystrophy (FSHD), a common hereditary myopathy, is characterized by atrophy and weakness of selective muscle groups. FSHD is considered an autosomal dominant disease with incomplete penetrance and unpredictable variability of clinical expression within families. Mice overexpressing FRG1 (FSHD region gene 1), a candidate gene for this disease, develop a progressive myopathy with features of the human disorder. Here, we show that in FRG1-overexpressing mice, fast muscles, which are the most affected by the dystrophic process, display anomalous fast skeletal troponin T (fTnT) isoform, resulting from the aberrant splicing of the Tnnt3 mRNA that precedes the appearance of dystrophic signs. We determine that muscles of FRG1 mice develop less strength due to impaired contractile properties of fast-twitch fibers associated with an anomalous MyHC-actin ratio and a reduced sensitivity to Ca(2+). We demonstrate that the decrease of Ca(2+) sensitivity of fast-twitch fibers depends on the anomalous troponin complex and can be rescued by the substitution with the wild-type proteins. Finally, we find that the presence of aberrant splicing isoforms of TNNT3 characterizes dystrophic muscles in FSHD patients. Collectively, our results suggest that anomalous TNNT3 profile correlates with the muscle impairment in both humans and mice. On the basis of these results, we propose that aberrant fTnT represents a biological marker of muscle phenotype severity and disease progression. PMID:24305066

Sancisi, Valentina; Germinario, Elena; Esposito, Alessandra; Morini, Elisabetta; Peron, Samantha; Moggio, Maurizio; Tomelleri, Giuliano; Danieli-Betto, Daniela; Tupler, Rossella

2014-01-15

414

Reliability prediction for the SLOWPOKE demonstration reactor building heating demonstration  

Microsoft Academic Search

The SLOWPOKE demonstration reactor (SDR) is a new prototype heating reactor, nominally 2 MW(thermal), developed by Atomic Energy of Canada Limited at the Whiteshell Laboratories. This project is part of a program to demonstrate the concept of supplying low-grade heat up to 10 MW(thermal) to localized district heating grids from an unpressurized nuclear heating source using a low-enriched, CANDU-type fuel.

D. J. Winfield; D. Cole; L. G. I. Bennett

1991-01-01

415

Cardiomyopathy in ?-kinase 3 (ALPK3)-deficient mice.  

PubMed

Cardiomyopathy developed in mice deficient for ?-kinase 3 (ALPK3), a nuclear kinase previously implicated in the differentiation of cardiomyocytes. Alpk3 (-/-) mice were produced according to normal Mendelian ratios and appeared normal except for a nonprogressive cardiomyopathy that had features of both hypertrophic and dilated forms of cardiomyopathy. Cardiac hypertrophy in Alpk3 (-/-) mice was characterized by increased thickness of both left and right ventricular (LV and RV) walls and by markedly increased heart weight and increased heart weight/body weight and heart weight/tibia length ratios. Magnetic resonance imaging studies confirmed the increased thickness in both septal and LV free walls at end-diastole, although there was no significant change in LV wall thickness at end-systole. Myocardial hypertrophy was the predominant feature in Alpk3 (-/-) mice, but several changes more typically associated with dilated cardiomyopathy included a marked increase in end-diastolic and end-systolic LV volume, as well as reduced cardiac output, stroke volume, and ejection fractions, suggesting LV chamber dilation. Magnetic resonance imaging showed a 50% reduction in both septal and free wall LV contractility in Alpk3 (-/-) mice. Interstitial fibrosis and inflammation were notably absent in Alpk3 (-/-) mice; however, light and electron microscopy revealed altered cardiomyocyte architecture, characterized by reduced numbers of abnormal intercalated discs being associated with mild disarray of myofibrils. These lesions could account for the impaired contractility of the myofibrillar apparatus and contribute to the pathogenesis of cardiomyopathy in Alpk3 (-/-) mice. PMID:21441111

Van Sligtenhorst, I; Ding, Z-M; Shi, Z-Z; Read, R W; Hansen, G; Vogel, P

2012-01-01

416

Comparative analysis of single and combined APP/APLP knockouts reveals reduced spine density in APP-KO mice that is prevented by APPs? expression  

PubMed Central

Synaptic dysfunction and synapse loss are key features of Alzheimer’s pathogenesis. Previously, we showed an essential function of APP and APLP2 for synaptic plasticity, learning and memory. Here, we used organotypic hippocampal cultures to investigate the specific role(s) of APP family members and their fragments for dendritic complexity and spine formation of principal neurons within the hippocampus. Whereas CA1 neurons from APLP1-KO or APLP2-KO mice showed normal neuronal morphology and spine density, APP-KO mice revealed a highly reduced dendritic complexity in mid-apical dendrites. Despite unaltered morphology of APLP2-KO neurons, combined APP/APLP2-DKO mutants showed an additional branching defect in proximal apical dendrites, indicating redundancy and a combined function of APP and APLP2 for dendritic architecture. Remarkably, APP-KO neurons showed a pronounced decrease in spine density and reductions in the number of mushroom spines. No further decrease in spine density, however, was detectable in APP/APLP2-DKO mice. Mechanistically, using APPs?-KI mice lacking transmembrane APP and expressing solely the secreted APPs? fragment we demonstrate that APPs? expression alone is sufficient to prevent the defects in spine density observed in APP-KO mice. Collectively, these studies reveal a combined role of APP and APLP2 for dendritic architecture and a unique function of secreted APPs for spine density.

2014-01-01

417

Comparative analysis of single and combined APP/APLP knockouts reveals reduced spine density in APP-KO mice that is prevented by APPs? expression.  

PubMed

Synaptic dysfunction and synapse loss are key features of Alzheimer's pathogenesis. Previously, we showed an essential function of APP and APLP2 for synaptic plasticity, learning and memory. Here, we used organotypic hippocampal cultures to investigate the specific role(s) of APP family members and their fragments for dendritic complexity and spine formation of principal neurons within the hippocampus. Whereas CA1 neurons from APLP1-KO or APLP2-KO mice showed normal neuronal morphology and spine density, APP-KO mice revealed a highly reduced dendritic complexity in mid-apical dendrites. Despite unaltered morphology of APLP2-KO neurons, combined APP/APLP2-DKO mutants showed an additional branching defect in proximal apical dendrites, indicating redundancy and a combined function of APP and APLP2 for dendritic architecture. Remarkably, APP-KO neurons showed a pronounced decrease in spine density and reductions in the number of mushroom spines. No further decrease in spine density, however, was detectable in APP/APLP2-DKO mice. Mechanistically, using APPs?-KI mice lacking transmembrane APP and expressing solely the secreted APPs? fragment we demonstrate that APPs? expression alone is sufficient to prevent the defects in spine density observed in APP-KO mice. Collectively, these studies reveal a combined role of APP and APLP2 for dendritic architecture and a unique function of secreted APPs for spine density. PMID:24684730

Weyer, Sascha W; Zagrebelsky, Marta; Herrmann, Ulrike; Hick, Meike; Ganss, Lennard; Gobbert, Julia; Gruber, Morna; Altmann, Christine; Korte, Martin; Deller, Thomas; Müller, Ulrike C

2014-01-01

418

Dynamic features of combustion  

NASA Technical Reports Server (NTRS)

The dynamic features of combustion are discussed for four important cases: ignition, inflammation, explosion, and detonation. Ignition, the initiation of a self-sustained exothermic process, is considered in the simplest case of a closed thermodynamic system and its stochastic distribution. Inflammation, the initiation and propagation of self-sustained flames, is presented for turbulent flow. Explosion, the dynamic effects caused by the deposition of exothermic energy in a compressible medium, is illustrated by self-similar blast waves with energy deposition at the front and the adiabatic non-self-similar wave. Detonation, the most comprehensive illustration of all the dynamic effects of combustion, is discussed with a phenomenological account of the development and structure of the wave.

Oppenheim, A. K.

1985-01-01

419

Toll-Like Receptor 5 Stimulation Protects Mice from Acute Clostridium difficile Colitis?  

PubMed Central

Clostridium difficile is a spore-forming bacterium that infects the lower intestinal tract of humans and is the most common known cause of diarrhea among hospitalized patients. Clostridium difficile colitis is mediated by toxins and develops during or following antibiotic administration. We have used a murine model of C. difficile infection, which reproduces the major features of the human disease, to study the effect of innate immune activation on resistance to C. difficile infection. We found that administration of purified Salmonella-derived flagellin, a Toll-like receptor 5 (TLR5) agonist, protects mice from C. difficile colitis by delaying C. difficile growth and toxin production in the colon and cecum. TLR5 stimulation significantly improves pathological changes in the cecum and colon of C. difficile-infected mice and reduces epithelial cell loss. Flagellin treatment reduces epithelial apoptosis in the large intestine, thereby protecting the integrity of the intestinal epithelial barrier during C. difficile infection. We demonstrate that restoring intestinal innate immune tone by TLR stimulation in antibiotic-treated mice ameliorates intestinal inflammation and prevents death from C. difficile colitis, potentially providing an approach to prevent C. difficile-induced pathology.

Jarchum, Irene; Liu, Mingyu; Lipuma, Lauren; Pamer, Eric G.

2011-01-01

420

Toll-like receptor 5 stimulation protects mice from acute Clostridium difficile colitis.  

PubMed

Clostridium difficile is a spore-forming bacterium that infects the lower intestinal tract of humans and is the most common known cause of diarrhea among hospitalized patients. Clostridium difficile colitis is mediated by toxins and develops during or following antibiotic administration. We have used a murine model of C. difficile infection, which reproduces the major features of the human disease, to study the effect of innate immune activation on resistance to C. difficile infection. We found that administration of purified Salmonella-derived flagellin, a Toll-like receptor 5 (TLR5) agonist, protects mice from C. difficile colitis by delaying C. difficile growth and toxin production in the colon and cecum. TLR5 stimulation significantly improves pathological changes in the cecum and colon of C. difficile-infected mice and reduces epithelial cell loss. Flagellin treatment reduces epithelial apoptosis in the large intestine, thereby protecting the integrity of the intestinal epithelial barrier during C. difficile infection. We demonstrate that restoring intestinal innate immune tone by TLR stimulation in antibiotic-treated mice ameliorates intestinal inflammation and prevents death from C. difficile colitis, potentially providing an approach to prevent C. difficile-induced pathology. PMID:21245274

Jarchum, Irene; Liu, Mingyu; Lipuma, Lauren; Pamer, Eric G

2011-04-01

421

Mice deficient in Epg5 exhibit selective neuronal vulnerability to degeneration  

PubMed Central

The molecular mechanism underlying the selective vulnerability of certain neuronal populations associated with neurodegenerative diseases remains poorly understood. Basal autophagy is important for maintaining axonal homeostasis and preventing neurodegeneration. In this paper, we demonstrate that mice deficient in the metazoan-specific autophagy gene Epg5/epg-5 exhibit selective damage of cortical layer 5 pyramidal neurons and spinal cord motor neurons. Pathologically, Epg5 knockout mice suffered muscle denervation, myofiber atrophy, late-onset progressive hindquarter paralysis, and dramatically reduced survival, recapitulating key features of amyotrophic lateral sclerosis (ALS). Epg5 deficiency impaired autophagic flux by blocking the maturation of autophagosomes into degradative autolysosomes, leading to accumulation of p62 aggregates and ubiquitin-positive inclusions in neurons and glial cells. Epg5 knockdown also impaired endocytic trafficking. Our study establishes Epg5-deficient mice as a model for investigating the pathogenesis of ALS and indicates that dysfunction of the autophagic–endolysosomal system causes selective damage of neurons associated with neurodegenerative diseases.

Zhao, Hongyu; Wang, Xingwei; Xu, Lanjun; Miao, Lin; Feng, Du; Chen, Quan; Kovacs, Attila L.; Fan, Dongsheng

2013-01-01

422

Truncated dystrophins reduce muscle stiffness in the extensor digitorum longus muscle of mdx mice.  

PubMed

Muscle stiffness is a major clinical feature in Duchenne muscular dystrophy (DMD). DMD is the most common lethal inherited muscle-wasting disease in boys, and it is caused by the lack of the dystrophin protein. We recently showed that the extensor digitorum longus (EDL) muscle of mdx mice (a DMD mouse model) exhibits disease-associated muscle stiffness. Truncated micro- and mini-dystrophins are the leading candidates for DMD gene therapy. Unfortunately, it has never been clear whether these truncated genes can mitigate muscle stiffness. To address this question, we examined the passive properties of the EDL muscle in transgenic mdx mice that expressed a representative mini- or micro-gene (?H2-R15, ?R2-15/?R18-23/?C, or ?R4-23/?C). The passive properties were measured at the ages of 6 and 20 mo and compared with those of age-matched wild-type and mdx mice. Despite significant truncation of the gene, surprisingly, the elastic and viscous properties were completely restored to the wild-type level in every transgenic strain we examined. Our results demonstrated for the first time that truncated dystrophin genes may effectively treat muscle stiffness in DMD. PMID:23221959

Hakim, Chady H; Duan, Dongsheng

2013-02-15

423

Feature tracking and aging  

PubMed Central

There are conflicting results regarding the effect of aging on second-order motion processing (i.e., motion defined by attributes other than luminance, such as contrast). Two studies (Habak and Faubert, 2000; Tang and Zhou, 2009) found that second-order motion processing was more vulnerable to aging than first-order motion processing. Conversely, Billino et al. (2011) recently found that aging affected first- and second-order motion processing by similar proportions. These three studies used contrast-defined motion as a second-order stimulus, but there can be at least two potential issues when using such a stimulus to evaluate age-related sensitivity losses. First, it has been shown that the motion system processing contrast-defined motion varies depending on the stimulus parameters. Thus, although all these three studies assumed that their contrast-defined motion was processed by a low-level second-order motion system, this was not necessarily the case. The second potential issue is that contrast-defined motion consists in a contrast modulation of a texture rich in high spatial frequencies and aging mainly affects contrast sensitivity at high spatial frequencies. Consequently, some age-related sensitivity loss to second-order motion could be due to a lower sensitivity to the texture rather than to motion processing per se. To avoid these two potential issues, we used a second-order motion stimulus void of high spatial frequencies and which has been shown to be processed by a high-level feature tracking motion system, namely fractal rotation (Lagacé-Nadon et al., 2009). We found an age-related deficit on second-order motion processing at all temporal frequencies including the ones for which no age-related effect on first-order motion processing was observed. We conclude that aging affects the ability to track features. Previous age-related results on second-order and global motion processing are discussed in light of these findings.

Allard, Remy; Lagace-Nadon, Sarah; Faubert, Jocelyn

2013-01-01

424

Extraction of edge feature in cardiovascular image  

NASA Astrophysics Data System (ADS)

Extraction of edge feature and accurate measurement of vascular diameter in cardiovascular image are the bases for labeling the coronary hierarchy, 3D refined reconstruction of the coronary arterial tree and accurate fusion between the calculated 3D vascular trees and other views. In order to extract vessels from the image, the grayscale minimization of the circle template and differential edge detection are put forward. Edge pixels of the coronary artery are set according to maximization of the differential value. The edge lines are determined after the edge pixels are smoothed by B-Spline function. The assessment of feature extraction is demonstrated by the excellent performance in computer simulation and actual application.

Lu, Jianrong; Chen, Dongqing; Yu, Daoyin; Liu, Xiaojun

2001-09-01

425

Deployable optical telescope ground demonstration  

NASA Astrophysics Data System (ADS)

The deployable optical telescope, the second project of the Air Force Research Laboratory's Integrated Ground Demonstration Laboratory, will demonstrate critical integration technologies associated with the next generation of beam expanders for space-based laser systems and large apertures for tactical surveillance systems. AFRL's development will be carried in cooperation with the contractor community and have direct ties to the future program offices that will utilize the DOT technologies. A flow down of total wavefront error acceptable for future operational systems has been used to derive DOT experiment requirements. The sub-scale DOT will demonstrate the initial deployment of a segmented primary and secondary tower in a 1-g laboratory environment.

Bell, Kevin D.; Moser, Ruth L.; Powers, Michael K.; Erwin, R. Scott

2000-07-01

426

Reprogramming in vivo produces teratomas and iPS cells with totipotency features.  

PubMed

Reprogramming of adult cells to generate induced pluripotent stem cells (iPS cells) has opened new therapeutic opportunities; however, little is known about the possibility of in vivo reprogramming within tissues. Here we show that transitory induction of the four factors Oct4, Sox2, Klf4 and c-Myc in mice results in teratomas emerging from multiple organs, implying that full reprogramming can occur in vivo. Analyses of the stomach, intestine, pancreas and kidney reveal groups of dedifferentiated cells that express the pluripotency marker NANOG, indicative of in situ reprogramming. By bone marrow transplantation, we demonstrate that haematopoietic cells can also be reprogrammed in vivo. Notably, reprogrammable mice present circulating iPS cells in the blood and, at the transcriptome level, these in vivo generated iPS cells are closer to embryonic stem cells (ES cells) than standard in vitro generated iPS cells. Moreover, in vivo iPS cells efficiently contribute to the trophectoderm lineage, suggesting that they achieve a more plastic or primitive state than ES cells. Finally, intraperitoneal injection of in vivo iPS cells generates embryo-like structures that express embryonic and extraembryonic markers. We conclude that reprogramming in vivo is feasible and confers totipotency features absent in standard iPS or ES cells. These discoveries could be relevant for future applications of reprogramming in regenerative medicine. PMID:24025773

Abad, María; Mosteiro, Lluc; Pantoja, Cristina; Cañamero, Marta; Rayon, Teresa; Ors, Inmaculada; Graña, Osvaldo; Megías, Diego; Domínguez, Orlando; Martínez, Dolores; Manzanares, Miguel; Ortega, Sagrario; Serrano, Manuel

2013-10-17

427

Secondary classification using key features  

NASA Astrophysics Data System (ADS)

A new multiple level classification method is introduced. With an available feature set, classification can be done in several steps. After first step of the classification using the full feature set, the high confidence recognition result will lead to an end of the recognition process. Otherwise a secondary classification designed using partial feature set and the information available from earlier classification step will help classify the input further. In comparison with the existing methods, our method is aimed for increasing recognition accuracy and reliability. A feature selection mechanism with help of genetic algorithms is employed to select important features that provide maximum separability between classes under consideration. These features are then used to get a sharper decision on fewer classes in the secondary classification. The full feature set is still used in earlier classification to retain complete information. There are no features dumped as they would be in feature selection methods described in most related publications.

Govindaraju, Venu; Shi, Zhixin; Teredesai, A.

2000-12-01

428

3. VIEW OF DUPLEX (FEATURE 7), FACING NORTH. OFFICE (FEATURE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. VIEW OF DUPLEX (FEATURE 7), FACING NORTH. OFFICE (FEATURE 11) VISIBLE IN BACKGROUND. - Copper Canyon Camp of the International Smelting & Refining Company, Duplex, Copper Canyon, Battle Mountain, Lander County, NV

429

Rotating Cylinder Treatment System Demonstration  

EPA Science Inventory

In August 2008, a rotating cylinder treatment system (RCTSTM) demonstration was conducted near Gladstone, CO. The RCTSTM is a novel technology developed to replace the aeration/oxidation and mixing components of a conventional lime precipitation treatment s...

430

160 MW AFBC Demonstration Project.  

National Technical Information Service (NTIS)

The cost estimate, conceptual design and design criteria developed thus far are all based on an assumed boiler configuration and feed system. The actual boiler building arrangement and balance of plant requirements for the 160 MW AFBC Demonstration Projec...

W. W. Bowman N. L. Seagle

1984-01-01

431

Demonstrating Forces between Parallel Wires.  

ERIC Educational Resources Information Center

Describes a physics demonstration that dramatically illustrates the mutual repulsion (attraction) between parallel conductors using insulated copper wire, wooden dowels, a high direct current power supply, electrical tape, and an overhead projector. (WRM)

Baker, Blane

2000-01-01

432

Favorite Demonstrations for College Science  

NSDL National Science Digital Library

Peer-reviewed, classroom-tested, and tailored specifically for introductory science courses, Favorite Demonstrations is an essential complement to every college instructor's lesson plans. The book is an all-in-one compilation of 36 popular classroom demonstrations published since 1993 in the "Favorite Demonstration" column of NSTA's Journal of College Science Teaching. The collection begins with a chapter on safety, "The Rules of Research." From there, chapters emphasize conveying scientific principles while making them memorable. The demonstrations cover general science, biology, chemistry, Earth science, and physics while many illustrate the interdisciplinary nature of science by showing how the various subjects contribute to each other's knowledge base. Most are simple to prepare; use low-cost, readily available materials; and can be repeated throughout the day for back-to-back classes.

2004-01-01

433

Simple Demonstration of Corrosion Cells.  

National Technical Information Service (NTIS)

The objective is to reinforce and enhance the understanding of galvanic cells, anode cathode reactions and polarization phenomena. Complete instructions are given for laboratory demonstration to be performed by students.

P. J. Guichelaar M. W. Williams

1990-01-01

434

Classroom Demonstrations of Auditory Perception.  

ERIC Educational Resources Information Center

Presents activities to help students gain understanding about auditory perception. Describes demonstrations that cover topics, such as sound localization, wave cancellation, frequency/pitch variation, and the influence of media on sound propagation. (CMK)

Haws, LaDawn; Oppy, Brian J.

2002-01-01

435

Weapon Storage Technology Demonstration Facility.  

National Technical Information Service (NTIS)

The goals of the Weapon Storage Technology Demonstration Facility is to (1) improve monitoring of weapons storage facility security status, (2) to improve detection of unauthorized access into the storage facilities, and (3) enhance inventory accounting o...

G. A. Mann A. Sviridov K. Zimovets

2000-01-01

436

CT Demonstration of Caput Medusae  

ERIC Educational Resources Information Center

Maximum intensity and volume rendered CT displays of caput medusae are provided to demonstrate both the anatomy and physiology of this portosystemic shunt associated with portal hypertension. (Contains 2 figures.)

Weber, Edward C.; Vilensky, Joel A.

2009-01-01

437

Demonstration of the Fenton Reaction  

ERIC Educational Resources Information Center

The study demonstrates the Fenton reaction, which is carried out using the Fenton reagent that is used for groundwater and soil remediation. The Fenton reaction can be implicated in DNA damage, Alzheimer's disease, cardiovascular disease and ageing in general.

Luehrs, Dean C.; Roher, Alex E.

2007-01-01

438

Citrate Process Demonstration Plant Design.  

National Technical Information Service (NTIS)

This Bureau of Mines report presents the design for a commercial-sized flue gas desulfurization (FGD) demonstration plant that uses the citrate process. The goal of the Bureau's citrate process is to minimize the undesirable environmental impacts of indus...

W. I. Nissen R. S. Madenburg

1979-01-01

439

4 K Stirling Cryocooler Demonstration.  

National Technical Information Service (NTIS)

This report briefly summarizes the results and conclusions from an SBIR program intended to demonstrate an innovative Stirling cycle cryocooler concept for efficiently lifting heat from 4 K. Refrigeration at 4 K, a temperature useful for superconductors a...

W. D. Stacy

1992-01-01

440

PROPEL Electrodynamic Tether Demonstration Mission.  

National Technical Information Service (NTIS)

The PROPEL ('Propulsion using Electrodynamics') mission will demonstrate the operation of an electrodynamic tether propulsion system in low Earth orbit and advance its technology readiness level for multiple applications. The PROPEL mission has two primar...

B. E. Gilchrist B. M. Wiegmann C. H. Elder C. L. Johnson K. P. Fuhrhop L. Alexander M. Scadera R. P. Hoyt S. G. Bilen

2012-01-01

441

Demonstrate Transdisciplinary Training and Operations.  

National Technical Information Service (NTIS)

The purpose of the project directed by United Cerebral Palsy Associations was to demonstrate transdisciplinary training and operations as used in the care of the severely developmentally disabled. Four transdisciplinary teams participated in the training ...

1974-01-01

442

Rubens Flame-Tube Demonstration.  

ERIC Educational Resources Information Center

Investigates and explains the phenomenon associated with Rubens flame-tube demonstration, specifically the persistance of flames at regular intervals along the tube for few minutes after the gas is turned off. (GA)

Ficken, George W.; Stephenson, Francis C.

1979-01-01

443

Robust Tracking Using Particle Filter with a Hybrid Feature  

NASA Astrophysics Data System (ADS)

This paper presents a novel method for robust object tracking in video sequences using a hybrid feature-based observation model in a particle filtering framework. An ideal observation model should have both high ability to accurately distinguish objects from the background and high reliability to identify the detected objects. Traditional features are better at solving the former problem but weak in solving the latter one. To overcome that, we adopt a robust and dynamic feature called Grayscale Arranging Pairs (GAP), which has high discriminative ability even under conditions of severe illumination variation and dynamic background elements. Together with the GAP feature, we also adopt the color histogram feature in order to take advantage of traditional features in resolving the first problem. At the same time, an efficient and simple integration method is used to combine the GAP feature with color information. Comparative experiments demonstrate that object tracking with our integrated features performs well even when objects go across complex backgrounds.

Zhao, Xinyue; Satoh, Yutaka; Takauji, Hidenori; Kaneko, Shun'ichi

444

Feature selection for computer-aided polyp detection using MRMR  

NASA Astrophysics Data System (ADS)

In building robust classifiers for computer-aided detection (CAD) of lesions, selection of relevant features is of fundamental importance. Typically one is interested in determining which, of a large number of potentially redundant or noisy features, are most discriminative for classification. Searching all possible subsets of features is impractical computationally. This paper proposes a feature selection scheme combining AdaBoost with the Minimum Redundancy Maximum Relevance (MRMR) to focus on the most discriminative features. A fitness function is designed to determine the optimal number of features in a forward wrapper search. Bagging is applied to reduce the variance of the classifier and make a reliable selection. Experiments demonstrate that by selecting just 11 percent of the total features, the classifier can achieve better prediction on independent test data compared to the 70 percent of the total features selected by AdaBoost.

Yang, Xiaoyun; Tek, Boray; Beddoe, Gareth; Slabaugh, Greg

2010-03-01

445

Slant Borehole Demonstration Summary Report  

SciTech Connect

This report provides a summary of the demonstration project for development of a slant borehole to retrieve soil samples from beneath the SX-108 single-shell tank. It provides a summary of the findings from the demonstration activities and recommendations for tool selection and methods to deploy into the SX Tank Farm. Daily work activities were recorded on Drilling and Sampling Daily Work Record Reports. The work described in this document was performed during March and April 2000.

GARDNER, M.G.

2000-07-19

446

Yo-Yo Pull Demonstration  

ERIC Educational Resources Information Center

A popular demonstration involves placing a yo-yo on a level table and gently pulling the string horizontally when it is wrapped to come out below the center of the yo-yo's axis. Students are then asked to predict which way the yo-yo will move. A similar demonstration is performed with a tricycle by pulling forward on a pedal with the pedal down in…

Layton, William

2013-01-01

447

Lunar Water Resource Demonstration (LWRD)  

NASA Technical Reports Server (NTRS)

Lunar Water Resource Demonstration (LWRD) is part of RESOLVE (Regolith and Environment Science & Oxygen and Lunar Volatile Extraction). RESOLVE is an ISRU ground demonstration: (1) A rover to explore a permanently shadowed crater at the south or north pole of the Moon (2) Drill core samples down to 1 meter (3) Heat the core samples to 150C (4) Analyze gases and capture water and/or hydrogen evolved (5) Use hydrogen reduction to extract oxygen from regolith

Muscatello, Anthony C.

2009-01-01

448

Chicxulub Impact Simulation Demonstrates Virtually all Observed Crater Features using Shock Damaged Rock Model  

NASA Astrophysics Data System (ADS)

New hydrocode impact calculations of the formation of the Chicxulub structure describe the detailed formation of the overturned flap marking the rim of the transient crater, the broad central uplift with an annular depression of the Moho-outside the central region, the outward collapse of the central peak, and the formation of annular faults and rings outside the radius of the initial transient crater. The structure formed in about 5 minutes. We use the Mohr-Coulomb-Anderson-Holmquist (MCAH) brittle damage model for rock fracture employing parameters for pristine and fractured rock measured in well understood laboratory experiments. We do not evoke other weakening mechanisms (e.g., acoustic fluidization). The projectile and the Earth's crust (thickness = 33 km) was modeled with the equation of state of granite and the underlying mantle (depth > 33 km) with the equation of state of dunite. We varied the 20 km/s velocity impactor radius from 5.0 to 7.5 km. For the target rocks, we assume a MCAH rheology with an undamaged internal friction (? u ) of 0.5 to 1.5, and shock and deformation-induced damaged internal friction (? d), of 0.1 to 0.5. The limiting von Mises strength was 2.4 GPa. The size of the damage zone is a function of integrated strain to failure. The rock damage distribution which is calculated during the impact evolution is approximately hemispherical and has a maximum radius of approximately twice that of the 40 to 55 km radius of the transient crater cavity. We found that the damage distribution determines: 1) the transient cavity dimensions ( e.g. depth of penetration), 2) Moho undulations, 3) ejecta lofting angles, 4) the occurrence of a central peak and the detailed dimensions, 5) the number and radii of terrace/slump faults, and 6) the radii and amplitude of final surface undulations (rings) extending outward of the circular faults. Within an integrated computation, we calculate the projectile penetration through 200 km of atmosphere, the formation of a 50 km deep transient cavity, and the collapse of the transient cavity to form the final crater morphology. Upon impact, the projectile lines the transient cavity and produces an associated melt layer. During the transient cavity collapse, the melt flows near the centerline and forms a thin layer on top of the peak ring. The peak ring forms as a result of the collision of the down ward flowing transient central peak with the nearly vertically launched cavity flow. The radius of the overturned stratigraphy is a measure of the transient cavity size and thus the energy of impact. The terraced zone faulting is initiated during the over folding of the ejecta curtain and proceeds during the slumping of material in front of the ejecta curtain. The slumping is part of the transient cavity collapse flow field. An asymmetric ring fault is formed that terminates the faulting in the terrace zone and also extends downward to the Moho. This ring is often designated as the crater rim. We calculate this diameter to be 150 km. We find ~20 km of central uplift of material above the Moho, and small positive and negative undulations of the Moho near the centerline. Finally a ~200 km diameter exterior topographic high ring is formed which is the result of the secondary impact of ejecta deposited upon the region of damaged surface material.

Okeefe, J.; Ahrens, T. J.

2002-12-01

449

Chicxulub Impact Simulation Demonstrates Virtually all Observed Crater Features using Shock Damaged Rock Model  

Microsoft Academic Search

New hydrocode impact calculations of the formation of the Chicxulub structure describe the detailed formation of the overturned flap marking the rim of the transient crater, the broad central uplift with an annular depression of the Moho-outside the central region, the outward collapse of the central peak, and the formation of annular faults and rings outside the radius of the

J. Okeefe; T. J. Ahrens

2002-01-01

450

Musicians demonstrate experience-dependent brainstem enhancement of musical scale features within continuously gliding pitch.  

PubMed

In contrast to language, where pitch patterns consist of continuous and curvilinear contours, musical pitch consists of relatively discrete, stair-stepped sequences of notes. Behavioral and neurophysiological studies suggest that both tone-language and music experience enhance the representation of pitch cues associated with a listener's domain of expertise, e.g., curvilinear pitch in language, discrete scale steps in music. We compared brainstem frequency-following responses (FFRs) of English-speaking musicians (musical pitch experience) and native speakers of Mandarin Chinese (linguistic pitch experience) elicited by rising and falling tonal sweeps that are exemplary of Mandarin tonal contours but uncharacteristic of the pitch patterns typically found in music. In spite of musicians' unfamiliarity with such glides, we find that their brainstem FFRs show enhancement of the stimulus where the curvilinear sweep traverses discrete notes along the diatonic musical scale. This enhancement was note specific in that it was not observed immediately preceding or following the scale tone of interest (passing note). No such enhancements were observed in Chinese listeners. These findings suggest that the musician's brainstem may be differentially tuned by long-term exposure to the pitch patterns inherent to music, extracting pitch in relation to a fixed, hierarchical scale. PMID:21906656

Bidelman, Gavin M; Gandour, Jackson T; Krishnan, Ananthanarayan

2011-10-10

451

Musicians demonstrate experience-dependent brainstem enhancement of musical scale features within continuously gliding pitch  

PubMed Central

In contrast to language, where pitch patterns consist of continuous and curvilinear contours, musical pitch consists of relatively discrete, stair-stepped sequences of notes. Behavioral and neurophysiological studies suggest that both tone-language and music experience enhance the representation of pitch cues associated with a listener’s domain of expertise, e.g., curvilinear pitch in language, discrete scale steps in music. We compared brainstem frequency-following responses (FFRs) of English-speaking musicians (musical pitch experience) and native speakers of Mandarin Chinese (linguistic pitch experience) elicited by rising and falling tonal sweeps that are exemplary of Mandarin tonal contours but uncharacteristic of the pitch patterns typically found in music. In spite of musicians’ unfamiliarity with such glides, we find that their brainstem FFRs show enhancement of the stimulus where the curvilinear sweep traverses discrete notes along the diatonic musical scale. This enhancement was note specific in that it was not observed immediately preceding or following the scale tone of interest (passing note). No such enhancements were observed in Chinese listeners. These findings suggest that the musician’s brainstem may be differentially tuned by long-term exposure to the pitch patterns inherent to music, extracting pitch in relation to a fixed, hierarchical scale.

Bidelman, Gavin M.; Gandour, Jackson T.; Krishnan, Ananthanarayan

2011-01-01