Surfactant protein C dampens inflammation by decreasing JAK/STAT activation during lung repair.

PubMed

Jin, Huiyan; Ciechanowicz, Andrzej K; Kaplan, Alanna R; Wang, Lin; Zhang, Ping-Xia; Lu, Yi-Chien; Tobin, Rachel E; Tobin, Brooke A; Cohn, Lauren; Zeiss, Caroline J; Lee, Patty J; Bruscia, Emanuela M; Krause, Diane S

2018-05-01

Surfactant protein C (SPC), a key component of pulmonary surfactant, also plays a role in regulating inflammation. SPC deficiency in patients and mouse models is associated with increased inflammation and delayed repair, but the key drivers of SPC-regulated inflammation in response to injury are largely unknown. This study focuses on a new mechanism of SPC as an anti-inflammatory molecule using SPC-TK/SPC-KO (surfactant protein C-thymidine kinase/surfactant protein C knockout) mice, which represent a novel sterile injury model that mimics clinical acute respiratory distress syndrome (ARDS). SPC-TK mice express the inducible suicide gene thymidine kinase from by the SPC promoter, which targets alveolar type 2 (AT2) cells for depletion in response to ganciclovir (GCV). We compared GCV-induced injury and repair in SPC-TK mice that have normal endogenous SPC expression with SPC-TK/SPC-KO mice lacking SPC expression. In contrast to SPC-TK mice, SPC-TK/SPC-KO mice treated with GCV exhibited more severe inflammation, resulting in over 90% mortality; there was only 8% mortality of SPC-TK animals. SPC-TK/SPC-KO mice had highly elevated inflammatory cytokines and granulocyte infiltration in the bronchoalveolar lavage (BAL) fluid. Consistent with a proinflammatory phenotype, immunofluorescence revealed increased phosphorylated signal transduction and activation of transcription 3 (pSTAT3), suggesting enhanced Janus kinase (JAK)/STAT activation in inflammatory and AT2 cells of SPC-TK/SPC-KO mice. The level of suppressor of cytokine signaling 3, an anti-inflammatory mediator that decreases pSTAT3 signaling, was significantly decreased in the BAL fluid of SPC-TK/SPC-KO mice. Hyperactivation of pSTAT3 and inflammation were rescued by AZD1480, a JAK1/2 inhibitor. Our findings showing a novel role for SPC in regulating inflammation via JAK/STAT may have clinical applications.

Cytotoxic and Antitumor Effects of Curzerene from Curcuma longa.

PubMed

Wang, Youdi; Li, Jiahong; Guo, Jiquan; Wang, Qiyou; Zhu, Shuguang; Gao, Siyuan; Yang, Chen; Wei, Min; Pan, Xuediao; Zhu, Wei; Ding, Dongmei; Gao, Ruiping; Zhang, Wei; Wang, Junye; Zang, Linquan

2017-01-01

Curzerene is a sesquiterpene and component used in oriental medicine. It was originally isolated from the traditional Chinese herbal medicine Curcuma rhizomes. In this study, anticancer activity of curzerene was examined in both in vitro and in vivo models. The result of the MTT assay showed that curzerene exhibited antiproliferative effects in SPC-A1 human lung adenocarcinoma cells in a time-dependent and dose-dependent manner. The anticancer IC 50 s were 403.8, 154.8, and 47.0 µM for 24, 48, and 72 hours, respectively. The flow cytometry analysis indicated curzerene arrested the cells in the G2/M cell cycle and promoted or induced apoptosis of SPC-A1 cells. The percentage of cells arrested in the G2/M phase increased from 9.26 % in the control group cells to 17.57 % in the cells treated with the highest dose (100 µM) of curzerene. Western blot and RT-PCR analysis demonstrated that curzerene induced the downregulation of GSTA1 protein and mRNA expressions in SPC-A1 cells. Tumor growth was significantly inhibited in SPC-A1 cell-bearing nude mice by using curzerene (135 mg/kg daily), meanwhile, curzerene did not significantly affect body mass and the organs of the mice, which may indicate that curzerene has limited toxicity and side effects in vivo . In conclusion, curzerene could inhibit the proliferation of SPC-A1 human lung adenocarcinoma cells line in both in vitro and in vivo models. Focusing on its relationship with GSTA1, curzerene could induce the downregulation of GSTA1 protein and mRNA expressions in SPC-A1 cells. Curzerene might be used as an anti-lung adenocarcinoma drug candidate compound for further development. Georg Thieme Verlag KG Stuttgart · New York.

Solar Probe Cup: Laboratory Performance

NASA Astrophysics Data System (ADS)

Case, A. W.; Kasper, J. C.; Korreck, K. E.; Stevens, M. L.; Larson, D. E.; Wright, K. H., Jr.; Gallagher, D. L.; Whittlesey, P. L.

2017-12-01

The Solar Probe Cup (SPC) is a Faraday Cup instrument that will fly on the Paker Solar Probe (PSP) spacecraft, orbiting the Sun at as close as 9.86 solar radii. The SPC instrument is designed to measure the thermal solar wind plasma (protons, alphas, and electrons) that will be encountered throughout its close encounter with the Sun. Due to the solar wind flow being primarily radial, the SPC instrument is pointed directly at the Sun, resulting in an extreme thermal environment that must be tolerated throughout the primary data collection phase. Laboratory testing has been performed over the past 6 months to demonstrate the instrument's performance relative to its requirements, and to characterize the measurements over the expected thermal range. This presentation will demonstrate the performance of the instrument as measured in the lab, describe the operational configurations planned for flight, and discuss the data products that will be created.

Characterization of nano-clay reinforced phytagel-modified soy protein concentrate resin.

PubMed

Huang, Xiaosong; Netravali, Anil N

2006-10-01

Phytagel and nano-clay particles were used to improve the mechanical and thermal properties and moisture resistance of soy protein concentrate (SPC) resin successfully. SPC and Phytagel were mixed together to form a cross-linked structure. The Phytagel-modified SPC resin (PH-SPC) showed improved tensile strength, modulus, moisture resistance, and thermal stability as compared to the unmodified SPC resin. The incorporation of 40% Phytagel and 20% glycerol led to an overall 340% increase in the tensile strength (over 50 MPa) and approximately 360% increase in the Young's modulus (over 710 MPa) of the SPC resin. Nano-clay was uniformly dispersed into PH-SPC resin to further improve the properties. The PH-SPC (40% Phytagel) resin modified with 7% clay nanoparticles (CPH-SPC) had a modulus of 2.1 GPa and a strength of 72.5 MPa. The dynamic mechanical properties such as storage modulus together with the glass transition temperature of the modified resins were also increased by the addition of clay nanoparticles. The moisture resistance of the CPH-SPC resin was higher as compared to both SPC and PH-SPC resins. The thermal stability of the CPH-SPC resin was seen to be higher as compared to the unmodified SPC.

Solid Phase Characterization of Tank 241-C-105 Grab Samples

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

Ely, T. M.; LaMothe, M. E.; Lachut, J. S.

The solid phase characterization (SPC) of three grab samples from single-shell Tank 241-C-105 (C-105) that were received at the laboratory the week of October 26, 2015, has been completed. The three samples were received and broken down in the 11A hot cells.

Interplay of the Glass Transition and the Liquid-Liquid Phase Transition in Water

NASA Astrophysics Data System (ADS)

Giovambattista, Nicolas

2013-03-01

Most liquids can form a single glass or amorphous state when cooled sufficiently fast (in order to prevent crystallization). However, there are a few substances that are relevant to scientific and technological applications which can exist in at least two different amorphous states, a property known as polyamorphism. Examples include silicon, silica, and in particular, water. In the case of water, experiments show the existence of a low-density (LDA) and high-density (HDA) amorphous ice that are separated by a dramatic, first-order like phase transition. It has been argued that the LDA-HDA transformation evolves into a first-order liquid-liquid phase transition (LLPT) at temperatures above the glass transition temperature Tg. However, obtaining direct experimental evidence of the LLPT has been challenging since the LLPT occurs at conditions where water rapidly crystallizes. In this talk, I will (i) discuss the general phenomenology of polyamorphism in water and its implications, and (ii) explore the effects of a LLPT on the pressure dependence of Tg(P) for LDA and HDA. Our study is based on computer simulations of two water models - one with a LLPT (ST2 model), and one without (SPC/E model). In the absence of a LLPT, Tg(P) for all glasses nearly coincide. Instead, when there is a LLPT, different glasses exhibit dramatically different Tg(P) loci which are directly linked with the LLPT. Available experimental data for Tg(P) are only consistent with the scenario that includes a LLPT (ST2 model) and hence, our results support the view that a LLPT may exist for the case of water.

Processing traits and digestibility of extruded dog foods with soy protein concentrate.

PubMed

Venturini, K S; Sarcinelli, M F; Baller, M A; Putarov, T C; Malheiros, E B; Carciofi, A C

2018-04-11

Soya bean protein concentrate (SPC) with two particle sizes were evaluated on extrusion parameters, kibble formation, digestibility and palatability of dog foods. Eight diets were extruded: PBM-control diet based on poultry by-product meal (PBM); GM-a diet in which corn gluten meal (GM) replaced 45% of the diet protein; cSPC15%, cSPC30% and cSPC45%-diets in which SPC of coarse particle size (600 μm) replaced 15%, 30% and 45% of the diet protein; and sSPC15%, sSPC30% and sSPC45%-diets in which SPC of small particle size (200 μm) replaced 15%, 30% and 45% of the diet protein. The digestibility of nutrients was evaluated for the PBM, GM, cSPC45% and sSPC45% diets, using six dogs per food. The PBM, GM and cSPC45% diets were compared for palatability. Data were submitted for analysis of variance, and the means were compared by polynomial contrasts or Tukey's test (p < .05). The cSPC increased the specific mechanical energy (SME) application, extrusion temperature and pressure linearly, resulting in lower kibble density and higher expansion and starch gelatinization (SG) (p < .01). When comparing the PBM, GM, cSPC45% and sSPC45% diets, higher SME, extrusion temperature and pressure, SG and kibble expansion were verified for the cSPC45% diet (p < .05). The DM, fat and crude protein digestibility were similar among diets. Faecal pH, ammonia and lactate did not differ, demonstrating that the removal of oligosaccharides and soluble non-starch polysaccharides of SPC produces an ingredient with mostly non-fermentable fibre. Dogs preferred the PBM to the GM diet (p < .05), but consumed the PBM and cSPC45% foods equally. In conclusion, SPC exhibited good extrusion functionality, favouring kibble expansion and SG, with high digestibility, similar to that of PBM. The removal of soluble compounds from soya beans resulted in an ingredient with low fermentable fibre content, which did not alter faecal formation or characteristics. © 2018 Blackwell Verlag GmbH.

Statistical process control for electron beam monitoring.

PubMed

López-Tarjuelo, Juan; Luquero-Llopis, Naika; García-Mollá, Rafael; Quirós-Higueras, Juan David; Bouché-Babiloni, Ana; Juan-Senabre, Xavier Jordi; de Marco-Blancas, Noelia; Ferrer-Albiach, Carlos; Santos-Serra, Agustín

2015-07-01

To assess the electron beam monitoring statistical process control (SPC) in linear accelerator (linac) daily quality control. We present a long-term record of our measurements and evaluate which SPC-led conditions are feasible for maintaining control. We retrieved our linac beam calibration, symmetry, and flatness daily records for all electron beam energies from January 2008 to December 2013, and retrospectively studied how SPC could have been applied and which of its features could be used in the future. A set of adjustment interventions designed to maintain these parameters under control was also simulated. All phase I data was under control. The dose plots were characterized by rising trends followed by steep drops caused by our attempts to re-center the linac beam calibration. Where flatness and symmetry trends were detected they were less-well defined. The process capability ratios ranged from 1.6 to 9.3 at a 2% specification level. Simulated interventions ranged from 2% to 34% of the total number of measurement sessions. We also noted that if prospective SPC had been applied it would have met quality control specifications. SPC can be used to assess the inherent variability of our electron beam monitoring system. It can also indicate whether a process is capable of maintaining electron parameters under control with respect to established specifications by using a daily checking device, but this is not practical unless a method to establish direct feedback from the device to the linac can be devised. Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Synchronous second primary cancers in patients with squamous esophageal cancer: clinical features and survival outcome.

PubMed

Lee, Jin Seo; Ahn, Ji Yong; Choi, Kee Don; Song, Ho June; Kim, Yong Hee; Lee, Gin Hyug; Jung, Hwoon-Yong; Ryu, Jin-Sook; Kim, Sung-Bae; Kim, Jong Hoon; Park, Seung-Il; Cho, Kyung-Ja; Kim, Jin-Ho

2016-03-01

Unexpected diagnosis of synchronous second primary cancers (SPC) complicates physicians' decision-making because clinical details of squamous esophageal cancer (EC) patients with SPC have been limited. We evaluated clinical features and treatment outcomes of patients with synchronous SPC detected during the initial staging of squamous EC. We identified a total of 317 consecutive patients diagnosed with squamous EC. Relevant clinical and cancer-specific information were reviewed retrospectively. EC patients with synchronous SPC were identified in 21 patients (6.6%). There were significant differences in median age (70 years vs. 63 years, p = 0.01), serum albumin level (3.3 g/dL vs. 3.9 g/dL, p < 0.01) and body mass index (20.4 kg/m(2) vs. 22.8 kg/m(2), p = 0.01) between EC patients with and without SPC. Head and neck, lung and gastric cancers accounted for 18.2%, 22.7%, and 18.2% of SPC, respectively. Positron emission tomography-computed tomography (PET-CT) detected four cases (18.2%) of SPC that were missed on CT. Management plans were altered in 13 of 21 patients (61.9%) with detected SPC. Curative esophagectomy was attempted in 28.6% of EC patients with SPC (vs. 59.1% of patients without SPC; p = 0.006). EC patients with SPC had significantly lower 5-year survival than patients without SPC (10.6% vs. 36.7%, p = 0.008). Synchronous SPC were found in 6.6% of squamous EC patients, and PET-CT contributed substantially to the detection of synchronous SPC. EC patients with SPC had poor survival due to challenges of providing stage-appropriate treatment.

Aliskiren/amlodipine as a single-pill combination in hypertensive patients: subgroup analysis of elderly patients, with metabolic risk factors or high body mass index

PubMed Central

Axthelm, Christoph; Sieder, Christian; Meister, Franziska; Pittrow, David; Kaiser, Edelgard

2013-01-01

Aims Blood pressure (BP) reduction in hypertensive patients is more difficult to achieve in the elderly or in the presence of comorbidities. We aimed to investigate the efficacy of the single-pill combination (SPC) aliskiren/amlodipine in hypertensive elderly patients, patients with high body mass index (BMI), with at least one metabolic risk factor, and/or type 2 diabetes mellitus (DM). Methods In an open-label non-randomized study, patients not adequately controlled by previous treatment with the SPC olmesarten 40/amlodipine 10 (phase 1) were switched to the SPC aliskiren 300/amlodipine 10 (phase 2). The present post-hoc analysis investigated BP reduction in phase 2 in the named subgroups. The EudraCT identifier was 2009-016693-33, ClinicalTrials.gov identifier NCT01113047. Results Of the 187 patients not adequately controlled in phase 1 and thus treated with the SPC aliskiren 300/amlodipine 10 in phase 2, 69 were of advanced age (≥65 years), 74 or 89 were overweight or obese (BMI 25.0–29.9 kg/m2 or ≥30 kg/m2, respectively), 91 had metabolic risk factors (without DM) and 41 had DM. At the beginning of phase 2, depending on the subgroup, baseline SBP was 168–169 mmHg and DBP 103–104 mmHg. After 4 weeks of treatment with aliskiren 300/amlodipine 10, SBP/DBP was lowered by −5.1/−4.8 mmHg in the total cohort, by −5.5/−5.1 mmHg in elderly patients, by −6.7/−5.5 in overweight and by −4.2/−4.5 mmHg in obese patients, by −6.4/−4.7 mmHg in patients with metabolic risk factors without DM, and by −3.3/−5.0 mmHg in DM patients. Limitations include low sample size, limited treatment duration and the fact that the post-hoc defined groups were not mutually exclusive. Conclusions In this study reflecting clinical practice, the aliskiren/amlodipine combination achieved effective BP reduction in elderly patients or with metabolic comorbidities, including DM that might be more difficult to treat. This consistent BP lowering pattern facilitates everyday care of patients who receive aliskiren/amlodipine. PMID:27536431

Solution structure of detergent micelles at conditions relevant to membrane protein crystallization.

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

Littrell, K.; Thiyagarajan, P.; Tiede, D.

1999-07-02

In this study small angle neutron scattering was used to characterize the formation of micelles in aqueous solutions of the detergents DMG and SPC as a function of detergent concentration and ionic strength of the solvent. The effects on the micelle structure of the additives glycerol and PEG, alone as well as in combination typical for actual membrane protein crystallization, were also explored. This research suggests that the micelles are cigar-like in form at the concentrations studied. The size of the micelles was observed to increase with increasing ionic strength but decrease with the addition of glycerol or PEG.

Effect of dignity therapy on end-of-life psychological distress in terminally ill Portuguese patients: A randomized controlled trial.

PubMed

Julião, Miguel; Oliveira, Fátima; Nunes, Baltazar; Carneiro, António Vaz; Barbosa, António

2017-12-01

Dignity therapy (DT) is a brief form of psychotherapy developed for patients living with a life-limiting illness that has demonstrated efficacy in treating several dimensions of end-of-life psychological distress. Our aim was to determine the influence of DT on demoralization syndrome (DS), the desire for death (DfD), and a sense of dignity (SoD) in terminally ill inpatients experiencing a high level of distress in a palliative care unit. A nonblinded phase II randomized controlled trial was conducted with 80 patients who were randomly assigned to one of two groups: the intervention group (DT + standard palliative care [SPC]) or the control group (SPC alone). The main outcomes were DS, DfD, and SoD, as measured according to DS criteria, the Desire for Death Rating Scale, and the Patient Dignity Inventory (PDI), respectively. All scales were assessed at baseline (day 1) and at day 4 of follow-up. This study is registered with http://www.controlled-trials.com/ISRCTN34354086. Of the 80 participants, 41 were randomized to DT and 39 to SPC. Baseline characteristics were similar between the two groups. DT was associated with a significant decrease in DS compared with SPC (DT DS prevalence = 12.1%; SPC DS prevalence = 60.0%; p < 0.001). Similarly, DT was associated with a significant decrease in DfD prevalence (DT DfD prevalence = 0%; SPC DfD prevalence = 14.3%; p = 0.054). Compared with participants allocated to the control group, those who received DT showed a statistically significant reduction in 19 of 25 PDI items. Dignity therapy had a beneficial effect on the psychological distress encountered by patients near the end of life. Our research suggests that DT is an important psychotherapeutic approach that should be included in clinical care programs, and it could help more patients to cope with their end-of-life experiences.

A mathematical model for an integrated self priming dielectric elastomer generator

NASA Astrophysics Data System (ADS)

Illenberger, Patrin K.; Wilson, Katherine E.; Henke, E.-F. Markus; Madawala, Udaya K.; Anderson, Iain A.

2017-04-01

Dielectric Elastomer Generators (DEG) can capture energy from natural movement sources such as wind, the tides and human locomotion. The harvested energy can be used for low power devices such as wireless sensor nodes and wearable electronics. A challenge for low power DEG is overcoming the losses associated with charge management. A circuit which can do this exists: the Self Priming Circuit (SPC) which consists of diodes and capacitors. The SPC is connected in parallel to the DEG where it transfers charge onto/o_ the DEG based on changes in the DEG capacitance. Modelling and experimental validation of the SPC have been performed in the past, allowing design and implementation of effective SPCs which match a particular DEG. While the SPC is effective, it is still an external circuit which adds additional mass and cost to the DEG. By splitting the DEG into separate capacitors and using them to build an SPC, the Integrated SPC (I-SPC) can be realized. This reduces the components required to build a SPC/DEG and improves the performance. This paper presents a mathematical model with experimental data of a first order I-SPC. Additionally, comparisons between the SPC and I-SPC are drawn.

On the calculation of solubilities via direct coexistence simulations: Investigation of NaCl aqueous solutions and Lennard-Jones binary mixtures.

PubMed

Espinosa, J R; Young, J M; Jiang, H; Gupta, D; Vega, C; Sanz, E; Debenedetti, P G; Panagiotopoulos, A Z

2016-10-21

Direct coexistence molecular dynamics simulations of NaCl solutions and Lennard-Jones binary mixtures were performed to explore the origin of reported discrepancies between solubilities obtained by direct interfacial simulations and values obtained from the chemical potentials of the crystal and solution phases. We find that the key cause of these discrepancies is the use of crystal slabs of insufficient width to eliminate finite-size effects. We observe that for NaCl crystal slabs thicker than 4 nm (in the direction perpendicular to the interface), the same solubility values are obtained from the direct coexistence and chemical potential routes, namely, 3.7 ± 0.2 molal at T = 298.15 K and p = 1 bar for the JC-SPC/E model. Such finite-size effects are absent in the Lennard-Jones system and are likely caused by surface dipoles present in the salt crystals. We confirmed that μs-long molecular dynamics runs are required to obtain reliable solubility values from direct coexistence calculations, provided that the initial solution conditions are near the equilibrium solubility values; even longer runs are needed for equilibration of significantly different concentrations. We do not observe any effects of the exposed crystal face on the solubility values or equilibration times. For both the NaCl and Lennard-Jones systems, the use of a spherical crystallite embedded in the solution leads to significantly higher apparent solubility values relative to the flat-interface direct coexistence calculations and the chemical potential values. Our results have broad implications for the determination of solubilities of molecular models of ionic systems.

Statistical process control as a tool for controlling operating room performance: retrospective analysis and benchmarking.

PubMed

Chen, Tsung-Tai; Chang, Yun-Jau; Ku, Shei-Ling; Chung, Kuo-Piao

2010-10-01

There is much research using statistical process control (SPC) to monitor surgical performance, including comparisons among groups to detect small process shifts, but few of these studies have included a stabilization process. This study aimed to analyse the performance of surgeons in operating room (OR) and set a benchmark by SPC after stabilized process. The OR profile of 499 patients who underwent laparoscopic cholecystectomy performed by 16 surgeons at a tertiary hospital in Taiwan during 2005 and 2006 were recorded. SPC was applied to analyse operative and non-operative times using the following five steps: first, the times were divided into two segments; second, they were normalized; third, they were evaluated as individual processes; fourth, the ARL(0) was calculated;, and fifth, the different groups (surgeons) were compared. Outliers were excluded to ensure stability for each group and to facilitate inter-group comparison. The results showed that in the stabilized process, only one surgeon exhibited a significantly shorter total process time (including operative time and non-operative time). In this study, we use five steps to demonstrate how to control surgical and non-surgical time in phase I. There are some measures that can be taken to prevent skew and instability in the process. Also, using SPC, one surgeon can be shown to be a real benchmark. © 2010 Blackwell Publishing Ltd.

The effects of increasing dietary levels of soy protein concentrate (SPC) on the immune responses and disease resistance (furunculosis) of vaccinated and non-vaccinated Atlantic salmon (Salmo salar L.) parr.

PubMed

Metochis, Christoforos P; Spanos, I; Auchinachie, N; Crampton, V O; Bell, J G; Adams, A; Thompson, K D

2016-12-01

Juvenile salmon, with an initial weight of 9 g, were fed three experimental diets, formulated to replace 35 (SPC35), 58 (SPC58) and 80 (SPC80) of high quality fishmeal (FM) with soy protein concentrate (SPC) in quadruplicate tanks. Higher dietary SPC inclusion was combined with increased supplementation of methionine, lysine, threonine and phosphorus. The experiment was carried out for 177 days. On day 92 salmon in each tank were bulk weighed. Post weighing eighty salmon from each tank were redistributed in two sets of 12 tanks. Salmon from the first set of tanks were vaccinated, while the second group was injected with phosphate buffer saline (PBS). Salmon were sampled on day 92 (pre-vaccination), day 94 (2 days post vaccination [dpv]/PBS injection [dpPBSinj]) and day 154 (62 dpv/dpPBSinj) of the trial for the assessment of their immune responses, prior to the performance of salmon bulk weights for each tank. On day 154, fish from each tank were again bulk weighed and then seventeen salmon per tank were redistributed in two sets of twelve tanks and intra-peritoneally infected with Aeromonas salmonicida. At Day 154, SPC80 demonstrated lower performance (weight gain, specific growth rate and thermal growth coefficient and feed conversion ratio) compared to SPC35 salmon. Reduced classical and total complement activities for salmon fed diets with over 58% of protein from SPC, were demonstrated prior to vaccination. Reduced alternative complement activity was detected for both SPC58 and SPC80 salmon at 2 dpv and for the SPC80 group at 62 dpv. Total and classical complement activities demonstrated no differences among the dietary groups after vaccination. Numerical increases in classical complement activity were apparent upon increased dietary SPC levels. Increased phagocytic activity (% phagocytosis and phagocytic index) was exhibited for the SPC58 group compared to SPC35 salmon at 62 dpPBSinj. No differences in serum lysozyme activity, total IgM, specific antibodies, protein, glucose and HKM respiratory burst were detected among the dietary groups at any timepoint or state. Mortalities as a result of the experimental infection only occurred in PBS-injected fish. No differences in mortality levels were demonstrated among the dietary groups. SPC58 diet supported both good growth and health in juvenile Atlantic salmon while SPC80 diet did not compromise salmon' immunity or resistance to intraperitoneally inflicted furunculosis. Copyright © 2016 Elsevier Ltd. All rights reserved.

A pilot evaluation of magnetic resonance imaging characteristics seen with solid papillary carcinomas of the breast in 4 patients.

PubMed

Zhang, Lina; Zhuang, Ling; Shi, Chang; Miao, Yanwei; Zhang, Weisheng; Song, Qingwei; Kang, Jianyun; Lang, Zhijin; Xin, Xuegang; Liu, Ailian; Hu, Jiani

2017-08-07

Solid papillary carcinoma (SPC) is a rare variant of breast papillary carcinoma with unique pathological morphology and biological behavior. There is only one case report on T 1 -MRI of SPC. In this study, we report our findings on this new category of papillary carcinoma to fill the gap in MRI characterization of SPC. This retrospective study included four pathology-confirmed in situ SPC patients. Conventional MRI, diffusion weighted imaging (DWI), and magnetic resonance spectroscopy (MRS) were performed with a 1.5 T whole-body MR scanner before surgical operation. The following characteristics of each lesion were recorded: signal intensity on T 2 WI/STIR and T 1 FSPGR, morphology, maximum lesion size, and time intensity curve (TIC) on dynamic contrast enhancement MRI (DCE-MRI), apparent diffusion coefficient (ADC) value from DWI, and Cho peak from MRS. Signal intensities of all lesions were heterogenous on T 2 WI/STIR and T 1 FSPGR. Mass enhancements were observed for all lesions with either oval or irregular shapes on DCE-MRI. The maximum lesion size ranged from 0.8 cm to 3.2 cm. All lesion margins were circumscribed, and internal enhancements were homogeneous or heterogeneous from DCE-MRI. TIC appeared with a rapid increase in initial contrast phases of all lesions. All lesions on DWI (b = 1000s/mm 2 ) were slightly hyperintense with an ADC value range of 1.3 × 10 -3  mm 2 /s to 1.9 × 10 -3  mm 2 /s. Cho peak was absent at 3.2 ppm for all lesions. MRI characteristics of SPC include heterogeneous signal intensity within the lesion on T 2 WI/STIR and T 1 FSPGR, mass enhancement with circumscribed margins, either oval or irregular shapes, and a rapid initial enhancement of TIC on DCE-MRI. ADC values and the absence of Cho peak may provide valuable information to distinguish SPC from other invasive breast carcinomas.

Integrating Palliative Care Into Comprehensive Cancer Centers: Consensus-Based Development of Best Practice Recommendations

PubMed Central

Stiel, Stephanie; Simon, Steffen T.; Schmitz, Andrea; van Oorschot, Birgitt; Stachura, Peter; Ostgathe, Christoph

2016-01-01

Background. International associations admit that specialized palliative care (SPC) is an obvious component of excellent cancer care. Nevertheless, gaps in integration at the international level have been identified. Recommendations for integrating SPC in clinical care, research, and education are needed, which are subject of the present study. Materials and Methods. A Delphi study, with three written Delphi rounds, including a face-to-face-meeting with a multiprofessional expert panel (n = 52) working in SPC in 15 German Comprehensive Cancer Centers (CCCs) funded by the German Cancer Aid was initiated. Initial recommendations are built on evidence-based literature. Consensus was defined in advance with ≥80% agreement based on the question of whether each recommendation was unambiguously formulated, relevant, and realizable for a CCC. Results. A total of 38 experts (73.1%) from 15 CCCs performed all three Delphi rounds. Consensus was achieved for 29 of 30 recommendations. High agreement related to having an organizationally and spatially independent palliative care unit (≥6 beds), a mobile multiprofessional SPC team, and cooperation with community-based SPC. Until round 3, an ongoing discussion was registered on hospice volunteers, a chair of palliative care, education in SPC among staff in emergency departments, and integration of SPC in decision-making processes such as tumor boards or consultation hours. Integration of SPC in decision-making processes was not consented by a low-rated feasibility (76.3%) due to staff shortage. Conclusion. Recommendations should be considered when developing standards for cancer center of excellence in Germany. Definition and implementation of indicators of integration of SPC in CCCs and evaluation of its effectiveness are current and future challenges. Implications for Practice: General and specialized palliative care (SPC) is an integral part of comprehensive cancer care. However, significant diversity concerning the design of SPC in the German Comprehensive Cancer Center (CCC) Network led to the establishment of consensual best practice recommendations for integration of SPC into the clinical structures, processes, research, and education throughout the CCC network. The recommendations contribute to a greater awareness relating to the strategic direction and development of SPC in CCCs. The access to information about SPC and access to offers regarding SPC shall be facilitated by implementing the recommendations in the course of treatment of patients with cancer. PMID:27440065

Propagation losses in undoped and n-doped polycrystalline silicon wire waveguides.

PubMed

Zhu, Shiyang; Fang, Q; Yu, M B; Lo, G Q; Kwong, D L

2009-11-09

Polycrystalline silicon (polySi) wire waveguides with width ranging from 200 to 500 nm are fabricated by solid-phase crystallization (SPC) of deposited amorphous silicon (a-Si) on SiO(2) at a maximum temperature of 1000 degrees C. The propagation loss at 1550 nm decreases from 13.0 to 9.8 dB/cm with the waveguide width shrinking from 500 to 300 nm while the 200-nm-wide waveguides exhibit quite large loss (>70 dB/cm) mainly due to the relatively rough sidewall of waveguides induced by the polySi dry etch. By modifying the process sequence, i.e., first patterning the a-Si layer into waveguides by dry etch and then SPC, the sidewall roughness is significantly improved but the polySi crystallinity is degraded, leading to 13.9 dB/cm loss in the 200-nm-wide waveguides while larger losses in the wider waveguides. Phosphorus implantation causes an additional loss in the polySi waveguides. The doping-induced optical loss increases relatively slowly with the phosphorus concentration increasing up to 1 x 10(18) cm(-3), whereas the 5 x 10(18) cm(-3) doped waveguides exhibit large loss due to the dominant free carrier absorption. For all undoped polySi waveguides, further 1-2 dB/cm loss reduction is obtained by a standard forming gas (10%H(2) + 90%N(2)) annealing owing to the hydrogen passivation of Si dangling bonds present in polySi waveguides, achieving the lowest loss of 7.9 dB/cm in the 300-nm-wide polySi waveguides. However, for the phosphorus doped polySi waveguides, the propagation loss is slightly increased by the forming gas annealing.

Physical Fitness of Soldiers Entering and Leaving Basic Combat Training

DTIC Science & Technology

2000-03-01

under sometimes miserably hot conditions (over 100° during post-BCT) to collect the data (alphabetical order): SGT Rebecca Gregg, SPC Greg Loomis, Mr...Clay Pandorf, SPC Ty Smith, SSG Roberta Worsham, and SGT Tanya Zigmont. SPC Smith, SPC Loomis and SGT Gregg graciously agreed to drive the...equipment back and forth to Ft. Jackson. SGT Gregg, SGT Zigmont and SPC Smith were instrumental in rapidly loading the data into a useable format. MAJ Joseph

Danish Palliative Care Database.

PubMed

Groenvold, Mogens; Adsersen, Mathilde; Hansen, Maiken Bang

2016-01-01

The aim of the Danish Palliative Care Database (DPD) is to monitor, evaluate, and improve the clinical quality of specialized palliative care (SPC) (ie, the activity of hospital-based palliative care teams/departments and hospices) in Denmark. The study population is all patients in Denmark referred to and/or in contact with SPC after January 1, 2010. The main variables in DPD are data about referral for patients admitted and not admitted to SPC, type of the first SPC contact, clinical and sociodemographic factors, multidisciplinary conference, and the patient-reported European Organisation for Research and Treatment of Cancer Quality of Life Questionaire-Core-15-Palliative Care questionnaire, assessing health-related quality of life. The data support the estimation of currently five quality of care indicators, ie, the proportions of 1) referred and eligible patients who were actually admitted to SPC, 2) patients who waited <10 days before admission to SPC, 3) patients who died from cancer and who obtained contact with SPC, 4) patients who were screened with European Organisation for Research and Treatment of Cancer Quality of Life Questionaire-Core-15-Palliative Care at admission to SPC, and 5) patients who were discussed at a multidisciplinary conference. In 2014, all 43 SPC units in Denmark reported their data to DPD, and all 9,434 cancer patients (100%) referred to SPC were registered in DPD. In total, 41,104 unique cancer patients were registered in DPD during the 5 years 2010-2014. Of those registered, 96% had cancer. DPD is a national clinical quality database for SPC having clinically relevant variables and high data and patient completeness.

Analyzing a Mature Software Inspection Process Using Statistical Process Control (SPC)

NASA Technical Reports Server (NTRS)

Barnard, Julie; Carleton, Anita; Stamper, Darrell E. (Technical Monitor)

1999-01-01

This paper presents a cooperative effort where the Software Engineering Institute and the Space Shuttle Onboard Software Project could experiment applying Statistical Process Control (SPC) analysis to inspection activities. The topics include: 1) SPC Collaboration Overview; 2) SPC Collaboration Approach and Results; and 3) Lessons Learned.

SPC-Prep. Instructor's Guide. Workplace Education. Project ALERT.

ERIC Educational Resources Information Center

Ruetz, Nancy

This instructor's guide contains materials for a course designed to prepare employees for statistical process control (SPC) training given at their workplace by refreshing math skills and building the concepts and vocabulary necessary to understand SPC in manufacturing environments. SPC-Prep 1 addresses the math skills necessary to perform SPC…

Total and Viable Legionella pneumophila Cells in Hot and Natural Waters as Measured by Immunofluorescence-Based Assays and Solid-Phase Cytometry ▿†

PubMed Central

Parthuisot, N.; Binet, M.; Touron-Bodilis, A.; Pougnard, C.; Lebaron, P.; Baudart, J.

2011-01-01

A new method was developed for the rapid and sensitive detection of viable Legionella pneumophila. The method combines specific immunofluorescence (IF) staining using monoclonal antibodies with a bacterial viability marker (ChemChrome V6 cellular esterase activity marker) by means of solid-phase cytometry (SPC). IF methods were applied to the detection and enumeration of both the total and viable L. pneumophila cells in water samples. The sensitivity of the IF methods coupled to SPC was 34 cells liter−1, and the reproducibility was good, with the coefficient of variation generally falling below 30%. IF methods were applied to the enumeration of total and viable L. pneumophila cells in 46 domestic hot water samples as well as in cooling tower water and natural water samples, such as thermal spring water and freshwater samples. Comparison with standard plate counts showed that (i) the total direct counts were always higher than the plate counts and (ii) the viable counts were higher than or close to the plate counts. With domestic hot waters, when the IF assay was combined with the viability test, SPC detected up to 3.4 × 103 viable but nonculturable L. pneumophila cells per liter. These direct IF methods could be a powerful tool for high-frequency monitoring of domestic hot waters or for investigating the occurrence of viable L. pneumophila in both man-made water systems and environmental water samples. PMID:21742913

A review of ultra-short pulse lasers for military remote sensing and rangefinding

NASA Astrophysics Data System (ADS)

Lamb, Robert A.

2009-09-01

Advances in ultra-short pulse laser technology have resulted in commercially available laser systems capable of generating high peak powers >1GW in tabletop systems. This opens the prospect of generating very wide spectral emissions with a combination of non-linear optical effects in photonic crystal fibres to produce supercontinuua in systems that are readily accessible to military applications. However, military remote sensing rarely requires bandwidths spanning two octaves and it is clear that efficient systems require controlled spectral emission in relevant bands. Furthermore, the limited spectral responsivity of focal plane arrays may impose further restriction on the usable spectrum. A recent innovation which temporally encodes a spectrum using group velocity dispersion allows detection with a photodiode, opening the prospect for high speed hyperspectral sensing and imaging. At the opposite end of the power spectrum, ultra-low power remote sensing using time-correlated single photon counting (SPC) has reduced the laser power requirement and demonstrated remote sensing over 5km during daylight with repetition rates of ~10MHz with ps pulses. Recent research has addressed uncorrelated SPC and waveform transmission to increase data rates for absolute rangefinding whilst avoiding range aliasing. This achievement opens the prospect of combining SPC with high repetition rate temporal encoding of supercontinuua to realise practical hyperspectral remote sensing lidar. The talk will present an overview of these technologies and present a concept which combines them into a single system for high-speed hyperspectral imaging and remote sensing.

SPC-Prep 1. Participant's Manual. Workplace Education. Project ALERT.

ERIC Educational Resources Information Center

Ruetz, Nancy

This companion document to the instructor's guide for a course designed to prepare employees for statistical process control (SPC) training given at their workplace by refreshing math skills and building the concepts and vocabulary necessary to understand SPC in manufacturing environments. SPC-Prep 1 addresses the math skills necessary to perform…

The cost-effectiveness of supportive periodontal care for patients with chronic periodontitis.

PubMed

Gaunt, Francesca; Devine, Maria; Pennington, Mark; Vernazza, Chris; Gwynnett, Erika; Steen, Nick; Heasman, Peter

2008-09-01

To systematically evaluate the evidence for effectiveness of supportive periodontal care (SPC) provided in specialist care and general practice for patients with chronic periodontitis; to construct a model for the cost effectiveness of SPC. Electronic database searches of MEDLINE, EMBASE and SCOPUS were performed with hand searching of relevant journals and Workshops of Periodontology. SPC for patients with chronic periodontitis, at least 12 months follow-up and clinical attachment level as a primary outcome. Three articles addressed the question (Nyman et al. 1975, Axelsson & Lindhe 1981, Cortellini et al. 1994): Deltas CAL for patients undergoing "specialist" SPC were 0.1 mm (2 years), 0.2 mm (6 years) and -0.01 mm (3 years) respectively. In generalist care the Deltas CAL during SPC were -2.2, -1.8 and -2.8 mm. Differences between specialist and generalist SPC were an extra 20.59 tooth years and 3.95 mm attachment loss for generalist SPC. Incremental cost-effectiveness ratios were an extra 288 euros for one tooth year or an extra 1503 euros/1 mm reduction in loss of attachment for SPC delivered in specialist care. SPC delivered in specialist as compared with general practice will result in greater stability of clinical attachment but this will be achieved at relatively greater cost.

A Homolog of Subtilisin-Like Proprotein Convertase 7 Is Essential to Anterior Neural Development in Xenopus

PubMed Central

Senturker, Sema; Thomas, John Terrig; Mateshaytis, Jennifer; Moos, Malcolm

2012-01-01

Background Subtilisin-like Proprotein Convertase 7 (SPC7) is a member of the subtilisin/kexin family of pro-protein convertases. It cleaves many pro-proteins to release their active proteins, including members of the bone morphogenetic protein (BMP) family of signaling molecules. Other SPCs are known to be required during embryonic development but corresponding data regarding SPC7 have not been reported previously. Methodology/Principal Findings We demonstrated that Xenopus SPC7 (SPC7) was expressed predominantly in the developing brain and eye, throughout the neural plate initially, then more specifically in the lens and retina primordia as development progressed. Since no prior functional information has been reported for SPC7, we used gain- and loss-of-function experiments to investigate the possibility that it may also convey patterning or tissue specification information similarly to Furin, SPC4, and SPC6. Overexpression of SPC7 was without effect. In contrast, injection of SPC7 antisense morpholino oligonucleotides (MO) into a single blastomere at the 2- or 4-cell stage produced marked disruption of head structures; anophthalmia was salient. Bilateral injections suppressed head and eye formation completely. In parallel with suppression of eye and brain development by SPC7 knockdown, expression of early anterior neural markers (Sox2, Otx2, Rx2, and Pax6) and late eye-specific markers (β-Crystallin and Opsin), and of BMP target genes such as Tbx2 and Tbx3, was reduced or eliminated. Taken together, these findings suggest a critical role for SPC7–perhaps, at least in part, due to activation of one or more BMPs–in early patterning of the anterior neural plate and its derivatives. Conclusion/Significance SPC7 is required for normal development of the eye and brain, possibly through processing BMPs, though other potential substrates cannot be excluded. PMID:22761776

Bending and splitting of spoof surface acoustic waves through structured rigid surface

NASA Astrophysics Data System (ADS)

Xie, Sujun; Ouyang, Shiliang; He, Zhaojian; Wang, Xiaoyun; Deng, Ke; Zhao, Heping

2018-03-01

In this paper, we demonstrated that a 90°-bended imaging of spoof surface acoustic waves with subwavelength resolution of 0.316λ can be realized by a 45° prism-shaped surface phononic crystal (SPC), which is composed of borehole arrays with square lattice in a rigid plate. Furthermore, by combining two identical prism-shaped phononic crystal to form an interface (to form a line-defect), the excited spoof surface acoustic waves can be split into bended and transmitted parts. The power ratio between the bended and transmitted surface waves can be tuned arbitrarily by adjusting the defect size. This acoustic system is believed to have potential applications in various multifunctional acoustic solutions integrated by different acoustical devices.

Solubility of NaCl in water and its melting point by molecular dynamics in the slab geometry and a new BK3-compatible force field

NASA Astrophysics Data System (ADS)

Kolafa, Jiří

2016-11-01

Saturated concentration of rock salt in water is determined by a simulation of brine in contact with a crystal in the slab geometry. The NaCl crystals are rotated to expose facets with higher Miller indices than [001] to brine. The rock salt melting point is obtained by both the standard and adiabatic simulations in the slab geometry with attention paid to finite size effects as well as to a possible influence of facets with higher Miller indices and applied stress. Two force fields are used, the Lennard-Jones-based model by Young and Cheatham with SPC/E water and the Kiss and Baranyai polarizable model with BK3 water. The latter model is refitted to thermomechanical properties of crystal NaCl leading to better values of solubility and the melting point.

Solubility of NaCl in water and its melting point by molecular dynamics in the slab geometry and a new BK3-compatible force field.

PubMed

Kolafa, Jiří

2016-11-28

Saturated concentration of rock salt in water is determined by a simulation of brine in contact with a crystal in the slab geometry. The NaCl crystals are rotated to expose facets with higher Miller indices than [001] to brine. The rock salt melting point is obtained by both the standard and adiabatic simulations in the slab geometry with attention paid to finite size effects as well as to a possible influence of facets with higher Miller indices and applied stress. Two force fields are used, the Lennard-Jones-based model by Young and Cheatham with SPC/E water and the Kiss and Baranyai polarizable model with BK3 water. The latter model is refitted to thermomechanical properties of crystal NaCl leading to better values of solubility and the melting point.

Zernike Wavefront Sensor Modeling Development for LOWFS on WFIRST-AFTA

NASA Technical Reports Server (NTRS)

Wang, Xu; Wallace, J. Kent; Shi, Fang

2015-01-01

WFIRST-AFTA design makes use of an existing 2.4m telescope for direct imaging of exoplanets. To maintain the high contrast needed for the coronagraph, wavefront error (WFE) of the optical system needs to be continuously sensed and controlled. Low Order Wavefront Sensing (LOWFS) uses the rejected starlight from an immediate focal plane to sense wavefront changes (mostly thermally induced low order WFE) by combining the LOWFS mask (a phase plate located at the small center region with reflective layer) with the starlight rejection masks, i.e. Hybrid Lyot Coronagraph (HLC)'s occulter or Shaped Pupil Coronagraph (SPC)'s field stop. Zernike wavefront sensor (ZWFS) measures phase via the phase-contrast method and is known to be photon noise optimal for measuring low order aberrations. Recently, ZWFS was selected as the baseline LOWFS technology on WFIST/AFTA for its good sensitivity, accuracy, and its easy integration with the starlight rejection mask. In this paper, we review the theory of ZWFS operation, describe the ZWFS algorithm development, and summarize various numerical sensitivity studies on the sensor performance. In the end, the predicted sensor performance on SPC and HLC configurations are presented.

Correlation between standard plate count and somatic cell count milk quality results for Wisconsin dairy producers.

PubMed

Borneman, Darand L; Ingham, Steve

2014-05-01

The objective of this study was to determine if a correlation exists between standard plate count (SPC) and somatic cell count (SCC) monthly reported results for Wisconsin dairy producers. Such a correlation may indicate that Wisconsin producers effectively controlling sanitation and milk temperature (reflected in low SPC) also have implemented good herd health management practices (reflected in low SCC). The SPC and SCC results for all grade A and B dairy producers who submitted results to the Wisconsin Department of Agriculture, Trade, and Consumer Protection, in each month of 2012 were analyzed. Grade A producer SPC results were less dispersed than grade B producer SPC results. Regression analysis showed a highly significant correlation between SPC and SCC, but the R(2) value was very small (0.02-0.03), suggesting that many other factors, besides SCC, influence SPC. Average SCC (across 12 mo) for grade A and B producers decreased with an increase in the number of monthly SPC results (out of 12) that were ≤ 25,000 cfu/mL. A chi-squared test of independence showed that the proportion of monthly SCC results >250,000 cells/mL varied significantly depending on whether the corresponding SPC result was ≤ 25,000 or >25,000 cfu/mL. This significant difference occurred in all months of 2012 for grade A and B producers. The results suggest that a generally consistent level of skill exists across dairy production practices affecting SPC and SCC. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

The Shuttle processing contractors (SPC) reliability program at the Kennedy Space Center - The real world

NASA Astrophysics Data System (ADS)

McCrea, Terry

The Shuttle Processing Contract (SPC) workforce consists of Lockheed Space Operations Co. as prime contractor, with Grumman, Thiokol Corporation, and Johnson Controls World Services as subcontractors. During the design phase, reliability engineering is instrumental in influencing the development of systems that meet the Shuttle fail-safe program requirements. Reliability engineers accomplish this objective by performing FMEA (failure modes and effects analysis) to identify potential single failure points. When technology, time, or resources do not permit a redesign to eliminate a single failure point, the single failure point information is formatted into a change request and presented to senior management of SPC and NASA for risk acceptance. In parallel with the FMEA, safety engineering conducts a hazard analysis to assure that potential hazards to personnel are assessed. The combined effort (FMEA and hazard analysis) is published as a system assurance analysis. Special ground rules and techniques are developed to perform and present the analysis. The reliability program at KSC is vigorously pursued, and has been extremely successful. The ground support equipment and facilities used to launch and land the Space Shuttle maintain an excellent reliability record.

National Guard Posture Statement 2010. America’s Indispensable Force

DTIC Science & Technology

2010-01-01

Michael T. Fuga, AS* SSG Carl R. Fuller, GA SPC Marcus S. Futrell, GA CSM Marilyn L. Gabbard, IA SGT Jerry L. Ganey Jr., GA SGT Seth K. Garceau, IA...Timoteo, NJ SPC Eric L. Toth, KY SSG Robin L. Towns Sr., MD SPC Seth R. Trahan, LA SPC Quoc Binh Tran, CA SSG Philip L. Travis, GA CW4 Chester W. Troxel...SFC Charles H. Warren, GA 1SG William T. Warren, AR SFC Mark C. Warren, OR SPC Glenn J. Watkins , CA MSG Davy N. Weaver, GA SGT Matthew A. Webber, MI SFC

Biomimicry of surfactant protein C.

PubMed

Brown, Nathan J; Johansson, Jan; Barron, Annelise E

2008-10-01

Since the widespread use of exogenous lung surfactant to treat neonatal respiratory distress syndrome, premature infant survival and respiratory morbidity have dramatically improved. Despite the effectiveness of the animal-derived surfactant preparations, there still remain some concerns and difficulties associated with their use. This has prompted investigation into the creation of synthetic surfactant preparations. However, to date, no clinically used synthetic formulation is as effective as the natural material. This is largely because the previous synthetic formulations lacked analogues of the hydrophobic proteins of the lung surfactant system, SP-B and SP-C, which are critical functional constituents. As a result, recent investigation has turned toward the development of a new generation of synthetic, biomimetic surfactants that contain synthetic phospholipids along with a mimic of the hydrophobic protein portion of lung surfactant. In this Account, we detail our efforts in creating accurate mimics of SP-C for use in a synthetic surfactant replacement therapy. Despite SP-C's seemingly simple structure, the predominantly helical protein is extraordinarily challenging to work with given its extreme hydrophobicity and structural instability, which greatly complicates the creation of an effective SP-C analogue. Drawing inspiration from Nature, two promising biomimetic approaches have led to the creation of rationally designed biopolymers that recapitulate many of SP-C's molecular features. The first approach utilizes detailed SP-C structure-activity relationships and amino acid folding propensities to create a peptide-based analogue, SP-C33. In SP-C33, the problematic and metastable polyvaline helix is replaced with a structurally stable polyleucine helix and includes a well-placed positive charge to prevent aggregation. SP-C33 is structurally stable and eliminates the association propensity of the native protein. The second approach follows the same design considerations but makes use of a non-natural, poly-N-substituted glycine or "peptoid" scaffold to circumvent the difficulties associated with SP-C. By incorporating unique biomimetic side chains in a non-natural backbone, the peptoid mimic captures both SP-C's hydrophobic patterning and its helical secondary structure. Despite the differences in structure, both SP-C33 and the SP-C peptoid mimic capture many requisite features of SP-C. In a surfactant environment, these analogues also replicate many of the key surface activities necessary for a functional biomimetic surfactant therapy while overcoming the difficulties associated with the natural protein. With improved stability, greater production potential, and elimination of possible pathogenic contamination, these biomimetic surfactant formulations offer not only the potential to improve the treatment of respiratory distress syndrome but also the opportunity to treat other respiratory-related disorders.

Secondary plastic closure of gastroschisis is associated with a lower incidence of mechanical ventilation.

PubMed

Dariel, Anne; Poocharoen, Wannisa; de Silva, Nicole; Pleasants, Hazel; Gerstle, Justin Ted

2015-02-01

Nonsurgical closure after primary silo placement, secondary plastic closure (SPC), has been used as an alternative to secondary surgical closure (SSC) in gastroschisis. The benefits described were closure without formal surgical procedure, cosmetic aspect, and minimization of intra-abdominal pressures. This study compared requirements for mechanical ventilation and general anesthesia, nutritional care, and outcomes between SPC and SSC. We included patients with primary staged-silo reduction with a 1-year minimum follow-up. SPC was performed at bedside with sedation using a nonadherent dressing. SSC was performed in operating room under general anesthesia using standard surgical techniques. This retrospective study included 64 patients, 23 SPC and 41 SSC. The characteristics of the two groups were comparable. Mechanical ventilation was used for 15 SPC and 41 SSC (p=0.0001) with a comparable median duration (5.5 and 6.0 days, not significant [NS]). General anesthesia was required for 9 SPC and 41 SSC (p<0.0001). Complications included one SPC and six SSC with necrotizing enterocolitis, zero SPC and four SSC with intestinal atresia, two SPC and four SSC with small bowel obstruction, zero SPC and one SSC with abdominal compartment syndrome resulting in a short bowel syndrome (NS). Median duration of parenteral nutrition (30 and 27 days), time to first feeds (14 and 14 days), time at or above minimal enteral feeding (22 and 17 days), time to full feeds (31 and 28 days), length of stay (LOS) in neonatal intensive care unit (24 and 23.5 days) and overall hospital LOS (37 and 36 days) were not statistically different between SPC and SSC patients without complications, respectively. These data were comparable for SPC and SSC patients with complications. Five SPC and six SSC developed an umbilical hernia (NS); two patients in each group required a surgical repair (NS). Plastic closure of gastroschisis after primary silo reduction is simple, safe, reproducible, and associated with a significant lower incidence of mechanical ventilation. Nutritional management and length of hospital stay were similar to conventional surgical closure for patients. Plastic closure allows nonoperative management without general anesthesia at patient's bedside, in comparison with surgical closure that must be performed under general anesthesia in the operating room. Plastic closure does not appear to be associated with more umbilical hernias in this retrospective study. Georg Thieme Verlag KG Stuttgart · New York.

Demonstrated Performance of the Solar Probe Cup

NASA Astrophysics Data System (ADS)

Case, A. W.; Kasper, J. C.; Korreck, K. E.; Stevens, M. L.; Daigneau, P.; Freeman, M.; Caldwell, D.; Gauron, T.; Wright, K. H.; Bergner, H.; Cirtain, J. W.; Larson, D.; Brodu, E.; Balat-Pichelin, M.

2013-12-01

The Solar Probe Cup (SPC) is a Faraday Cup being developed for the Solar Probe Plus (SPP) mission. SPP will be the first spacecraft to directly measure the solar environment near the Alfven point in the atmosphere of the Sun, approaching to within 10 solar radii of the center of the Sun. In order to make the observations of radially flowing solar wind needed to address questions of coronal and solar wind heating and acceleration, SPC must operate while looking directly at the Sun. As a result, SPC will face a harsh and unprecidented environment, with component temperatures exceeding 1000C at closest approach. SPC is similar in design and operation to the two Faraday Cup instruments on the Wind spacecraft, which have been making stable measurements of the solar wind near Earth for two decades, with two key differences. SPC must survive and operate at extreme temperatures due to the levels of solar flux near the Sun, and it must record the solar wind approximately one thousand times faster than the instruments on Wind to keep up with the rapid variations expected near the Sun. We present results of a demonstration model of SPC operated in laboratory reproductions of the near-Sun environment. In the last year, SPC has been exposed to simulated encounter solar fluxes and resulting temperature profiles using a vaccum chamber and modified IMAX film projectors. In addition, SPC has been exposed to realistic ion beams. We show that SPC can operate in these environments, and make the measurements required for the sucess of the Solar Probe mission. Based on the performance of our prototype, the expected cadence and sensitivity of SPC will be discussed, with a focus on its ability to distinguish between models of heating in the solar corona.

Electrostatic contribution from solvent in modulating single-walled carbon nanotube association

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

Ou, Shu-Ching; Patel, Sandeep, E-mail: sapatel@udel.edu

We perform all-atom molecular dynamics simulations to compute the potential of mean force (PMF) between two (10,10) single-walled carbon nanotubes solvated in pure nonpolarizable SPC/E and polarizable TIP4P-FQ water, at various temperatures. In general, the reversible work required to bring two nanotubes from a dissociated state (free energy reference) to contact state (free energy minimum) is more favorable and less temperature-dependent in TIP4P-FQ than in SPC/E water models. In contrast, molecular properties and behavior of water such as the spatially-resolved water number density (intertube, intratube, or outer regions), for TIP4P-FQ are more sensitive to temperature than SPC/E. Decomposition of themore » solvent-induced PMF into different spatial regions suggests that TIP4P-FQ has stronger temperature dependence; the opposing destabilizing/stabilizing contributions from intertube water and more distal water balance each other and suppress the temperature dependence of total association free energy. Further investigation of hydrogen bonding network in intertube water reveals that TIP4P-FQ retains fewer hydrogen bonds than SPC/E, which correlates with the lower water number density in this region. This reduction of hydrogen bonds affects the intertube water dipoles. As the intertube volume decreases, TIP4P-FQ dipole moment approaches the gas phase value; the distribution of dipole magnitude also becomes narrower due to less average polarization/perturbation from other water molecules. Our results imply that the reduction of water under confinement may seem trivial, but underlying effects to structure and free energetics are non-negligible.« less

The Annual Report of the National Shipbuilding Research Program (The Naval Shipbuilding Research Program)

DTIC Science & Technology

1986-08-29

Abrasives Work Planning for Shipyard SP&C Training Overcoating of Zinc Primers Citric Acid Cleaning - Phase II - Waterborne Coatings Economics of...members workout organizational problems with minimum government involvement a set of strong, committed, and sometimes fiercely independent panels and...01 Manual of Welding Planning and Design Guidelines - Phase III PANEL SP-3 Ship Design Considerations: Adaptation of Japanese Pre - 7 9 79 81 82 83 83

Study on the DNA-protein crosslinks induced by chromium (VI) in SPC-A1

NASA Astrophysics Data System (ADS)

Liu, Yanqun; Ding, Jianjun; Lu, Xiongbing; You, Hao

2018-01-01

Objective: This study was designed to investigate the effect of chromium (VI) on DNA-protein crosslinks (DPC) of SPC-A1 cells. Methods: We exposed SPC-A1 cells were cultured in 1640 medium and treated with the SPC-A1 cells in vitro to different concentrations of Hexavalent chromium Cr(VI) for 2h, the KC1-SDS precipitation assay were used to measure the DNA-protein cross-linking effect. Results: All the different concentrations of Cr(VI) could cause the increase of DPC coefficient in SPC-A1 cells. But this effect was not significant (P>0.05) at low concentrations; while in high concentration Cr(VI) induced SPC-A1 cells could produce DNA-protein cross-linking effect significantly (P<0.05). Conclusions: chromium (VI) could induce DNA-protein crosslink.

Statistical process control: separating signal from noise in emergency department operations.

PubMed

Pimentel, Laura; Barrueto, Fermin

2015-05-01

Statistical process control (SPC) is a visually appealing and statistically rigorous methodology very suitable to the analysis of emergency department (ED) operations. We demonstrate that the control chart is the primary tool of SPC; it is constructed by plotting data measuring the key quality indicators of operational processes in rationally ordered subgroups such as units of time. Control limits are calculated using formulas reflecting the variation in the data points from one another and from the mean. SPC allows managers to determine whether operational processes are controlled and predictable. We review why the moving range chart is most appropriate for use in the complex ED milieu, how to apply SPC to ED operations, and how to determine when performance improvement is needed. SPC is an excellent tool for operational analysis and quality improvement for these reasons: 1) control charts make large data sets intuitively coherent by integrating statistical and visual descriptions; 2) SPC provides analysis of process stability and capability rather than simple comparison with a benchmark; 3) SPC allows distinction between special cause variation (signal), indicating an unstable process requiring action, and common cause variation (noise), reflecting a stable process; and 4) SPC keeps the focus of quality improvement on process rather than individual performance. Because data have no meaning apart from their context, and every process generates information that can be used to improve it, we contend that SPC should be seriously considered for driving quality improvement in emergency medicine. Copyright © 2015 Elsevier Inc. All rights reserved.

Results of a multicentre randomised controlled trial of statistical process control charts and structured diagnostic tools to reduce ward-acquired meticillin-resistant Staphylococcus aureus: the CHART Project.

PubMed

Curran, E; Harper, P; Loveday, H; Gilmour, H; Jones, S; Benneyan, J; Hood, J; Pratt, R

2008-10-01

Statistical process control (SPC) charts have previously been advocated for infection control quality improvement. To determine their effectiveness, a multicentre randomised controlled trial was undertaken to explore whether monthly SPC feedback from infection control nurses (ICNs) to healthcare workers of ward-acquired meticillin-resistant Staphylococcus aureus (WA-MRSA) colonisation or infection rates would produce any reductions in incidence. Seventy-five wards in 24 hospitals in the UK were randomised into three arms: (1) wards receiving SPC chart feedback; (2) wards receiving SPC chart feedback in conjunction with structured diagnostic tools; and (3) control wards receiving neither type of feedback. Twenty-five months of pre-intervention WA-MRSA data were compared with 24 months of post-intervention data. Statistically significant and sustained decreases in WA-MRSA rates were identified in all three arms (P<0.001; P=0.015; P<0.001). The mean percentage reduction was 32.3% for wards receiving SPC feedback, 19.6% for wards receiving SPC and diagnostic feedback, and 23.1% for control wards, but with no significant difference between the control and intervention arms (P=0.23). There were significantly more post-intervention 'out-of-control' episodes (P=0.021) in the control arm (averages of 0.60, 0.28, and 0.28 for Control, SPC and SPC+Tools wards, respectively). Participants identified SPC charts as an effective communication tool and valuable for disseminating WA-MRSA data.

Mechanism of photodynamic inactivation of hepatocarcinoma cells with sulfonated aluminum phthalocyanine

NASA Astrophysics Data System (ADS)

Yu, Hong-Yu; Dong, Rong-Chun; Chen, Ji-Yao; Cai, Huai-Xin

1993-03-01

The mechanism of photodynamic therapy (PDT) with sulfonated aluminum phthalocyanine (AlSPC) studied with the human hepatocellular carcinoma cell line in culture is reported herein. Photofrin II (PII) was chosen as the control photosensitizer of AlSPC. Deuterium oxide (D2O), an enhancer of singlet oxygen (1O2); 1,3-diphenylisobenzofuran (DPBF), a quencher of 1O2: glycerol, a quencher of OH radical (OH(DOT)); superoxide dismutase (SOD), a quencher of O2- radical (O2-(DOT)); diethyldithiocarbamate (DDC), an inhibitor of SOD and glutathione peroxidase; were introduced into both the processes of photodynamic inactivation of human liver cancer cells in culture with AlSPC (AlSPC-PDT) and with PII (PII-PDT). The results suggest that: 1O2 is dominantly involved in both PII-PDT and AlSPC-PDT; O2-(DOT) is involved in AlSPC-PDT in a lower degree than 1O2, while almost not involved in PII-PDT; OH(DOT) is involved in PII-PDT in a lower degree than 1O2, while almost not involved in AlSPC-PDT.

Computation of methodology-independent single-ion solvation properties from molecular simulations. IV. Optimized Lennard-Jones interaction parameter sets for the alkali and halide ions in water

NASA Astrophysics Data System (ADS)

Reif, Maria M.; Hünenberger, Philippe H.

2011-04-01

The raw single-ion solvation free energies computed from atomistic (explicit-solvent) simulations are extremely sensitive to the boundary conditions and treatment of electrostatic interactions used during these simulations. However, as shown recently [M. A. Kastenholz and P. H. Hünenberger, J. Chem. Phys. 124, 224501 (2006), 10.1529/biophysj.106.083667; M. M. Reif and P. H. Hünenberger, J. Chem. Phys. 134, 144103 (2010)], the application of appropriate correction terms permits to obtain methodology-independent results. The corrected values are then exclusively characteristic of the underlying molecular model including in particular the ion-solvent van der Waals interaction parameters, determining the effective ion size and the magnitude of its dispersion interactions. In the present study, the comparison of calculated (corrected) hydration free energies with experimental data (along with the consideration of ionic polarizabilities) is used to calibrate new sets of ion-solvent van der Waals (Lennard-Jones) interaction parameters for the alkali (Li+, Na+, K+, Rb+, Cs+) and halide (F-, Cl-, Br-, I-) ions along with either the SPC or the SPC/E water models. The experimental dataset is defined by conventional single-ion hydration free energies [Tissandier et al., J. Phys. Chem. A 102, 7787 (1998), 10.1021/jp982638r; Fawcett, J. Phys. Chem. B 103, 11181] along with three plausible choices for the (experimentally elusive) value of the absolute (intrinsic) hydration free energy of the proton, namely, Δ G_hyd^{ominus }[H+] = -1100, -1075 or -1050 kJ mol-1, resulting in three sets L, M, and H for the SPC water model and three sets LE, ME, and HE for the SPC/E water model (alternative sets can easily be interpolated to intermediate Δ G_hyd^{ominus }[H+] values). The residual sensitivity of the calculated (corrected) hydration free energies on the volume-pressure boundary conditions and on the effective ionic radius entering into the calculation of the correction terms is also evaluated and found to be very limited. Ultimately, it is expected that comparison with other experimental ionic properties (e.g., derivative single-ion solvation properties, as well as data concerning ionic crystals, melts, solutions at finite concentrations, or nonaqueous solutions) will permit to validate one specific set and thus, the associated Δ G_hyd^{ominus }[H+] value (atomistic consistency assumption). Preliminary results (first-peak positions in the ion-water radial distribution functions, partial molar volumes of ionic salts in water, and structural properties of ionic crystals) support a value of Δ G_hyd^{ominus }[H+] close to -1100 kJ.mol-1.

Interservice Procedures for Instructional Systems Development. Phase 1. Analyze

DTIC Science & Technology

1975-08-01

exertion. 3. Kneeling or squatting . 4. Unusually cramped position. 5. Environmental conditions 1, Tropical environment. that influence task 2. Arctic...rerwuaiiiin s it tructiuna! settinqt s. -.--- No ruYle-s cni be stated that prescribe a Fi ’ spc ifir settiri for a Lask. Ho,.-ver, _"t B luidel&ines are given

Methods for microbiological quality assessment in drinking water: a comparative study.

PubMed

Helmi, K; Barthod, F; Méheut, G; Henry, A; Poty, F; Laurent, F; Charni-Ben-Tabassi, N

2015-03-01

The present study aimed to compare several methods for quantifying and discriminating between the different physiological states of a bacterial population present in drinking water. Flow cytometry (FCM), solid-phase cytometry (SPC), epifluorescence microscopy (MSP) and culture method performances were assessed by comparing the results obtained for different water samples. These samples, including chlorinated and non-chlorinated water, were collected in a drinking water treatment plant. Total bacteria were quantified by using SYBR Green II (for FCM) and 4',6'-diamino-2-phenylindole (DAPI) (for MSP), viable and non-viable bacteria were distinguished by using SYBR Green II and propidium iodide dual staining (for FCM), and active cells were distinguished by using CTC (for MSP) and Chemchrome V6 (for FCM and SPC). In our conditions, counts using microscopy and FCM were significantly correlated regarding total bacteria and active cells. Conversely, counts were not significantly similar using solid-phase and FCM for active bacteria. Moreover, the R2A medium showed that bacterial culturability could be recovered after chlorination. This study highlights that FCM appears to be a useful and powerful technique for drinking water production monitoring.

A Novel Method for Preparing Auxetic Foam from Closed-cell Polymer Foam Based on Steam Penetration and Condensation (SPC) Process.

PubMed

Fan, Donglei; Li, Minggang; Qiu, Jian; Xing, Haiping; Jiang, Zhiwei; Tang, Tao

2018-05-31

Auxetic materials are a class of materials possessing negative Poisson's ratio. Here we establish a novel method for preparing auxetic foam from closed-cell polymer foam based on steam penetration and condensation (SPC) process. Using polyethylene (PE) closed-cell foam as an example, the resultant foams treated by SPC process present negative Poisson's ratio during stretching and compression testing. The effect of steam-treated temperature and time on the conversion efficiency of negative Poisson's ratio foam is investigated, and the mechanism of SPC method for forming re-entrant structure is discussed. The results indicate that the presence of enough steam within the cells is a critical factor for the negative Poisson's ratio conversion in the SPC process. The pressure difference caused by steam condensation is the driving force for the conversion from conventional closed-cell foam to the negative Poisson's ratio foam. Furthermore, the applicability of SPC process for fabricating auxetic foam is studied by replacing PE foam by polyvinyl chloride (PVC) foam with closed-cell structure or replacing water steam by ethanol steam. The results verify the universality of SPC process for fabricating auxetic foams from conventional foams with closed-cell structure. In addition, we explored potential application of the obtained auxetic foams by SPC process in the fabrication of shape memory polymer materials.

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

Cooke, Gary A.; Pestovich, John A.; Huber, Heinz J.

This report presents the results for solid phase characterization (SPC) of solid samples removed from tank 241-C-108 (C-108) on August 12-13,2012, using the off-riser sampler. Samples were received at the 222-S Laboratory on August 13 and were described and photographed. The SPC analyses that were performed include scanning electron microscopy (SEM) using the ASPEX(R)l scanning electron microscope, X-ray diffraction (XRD) using the Rigaku(R) 2 MiniFlex X-ray diffractometer, and polarized light microscopy (PLM) using the Nikon(R) 3 Eclipse Pol optical microscope. The SEM is equipped with an energy dispersive X-ray spectrometer (EDS) to provide chemical information. Gary A. Cooke conducted themore » SEM analysis, John A. Pestovich performed the XRD analysis, and Dr. Heinz J. Huber performed the PLM examination. The results of these analyses are presented here.« less

Moto del Sole intorno al baricentro del sistema solare

NASA Astrophysics Data System (ADS)

Piovan, Luciano; Milani, Franco

2006-06-01

The paper discusses the Sun's motion around the barycentre of the Solar System determined by the ever-changing dispositon of the planets over approximately 2000 years. Files of high-quality data taken from international sites were used in common personal computers. The Sun shows a repetitive behaviour, where an apocycle (ApC, decennial period in which the Sun moves very far from the barycentre) is followed by a pericycle (PeC, decennial period in which the Sun moves very near the barycentre) and by another ApC, etc. Periodicities exist in the short period (supercycles, SpC, lasting about 40 years and made of two sequences ApC-PeC, each lasting 20 years), in the mean period (phases comprising a sequence of 4 to 5 SpC, then lasting approximately 160 or 200 years respectively, mean value 180 years), and in the long period (hypercycles, IpC, consisting of two phases, lasting approximately 360 or 400 years). During one phase, the successive ApCs start opposed to each other in ecliptical coordinates and end nearly superimposed; during the following phase the ApCs start superimposed one over the other and end opposed to each other in ecliptical coordinates. The phase length, whose mean value is about 180 years, is very near the modulation of the maxima of the sunspot cycle (178.7 years). The periodicities found are modulated mainly by the alignment of Jupiter, or by both Jupiter and Saturn, with the Sun and the barycentre of the Solar System.

Performance of statistical process control methods for regional surgical site infection surveillance: a 10-year multicentre pilot study.

PubMed

Baker, Arthur W; Haridy, Salah; Salem, Joseph; Ilieş, Iulian; Ergai, Awatef O; Samareh, Aven; Andrianas, Nicholas; Benneyan, James C; Sexton, Daniel J; Anderson, Deverick J

2017-11-24

Traditional strategies for surveillance of surgical site infections (SSI) have multiple limitations, including delayed and incomplete outbreak detection. Statistical process control (SPC) methods address these deficiencies by combining longitudinal analysis with graphical presentation of data. We performed a pilot study within a large network of community hospitals to evaluate performance of SPC methods for detecting SSI outbreaks. We applied conventional Shewhart and exponentially weighted moving average (EWMA) SPC charts to 10 previously investigated SSI outbreaks that occurred from 2003 to 2013. We compared the results of SPC surveillance to the results of traditional SSI surveillance methods. Then, we analysed the performance of modified SPC charts constructed with different outbreak detection rules, EWMA smoothing factors and baseline SSI rate calculations. Conventional Shewhart and EWMA SPC charts both detected 8 of the 10 SSI outbreaks analysed, in each case prior to the date of traditional detection. Among detected outbreaks, conventional Shewhart chart detection occurred a median of 12 months prior to outbreak onset and 22 months prior to traditional detection. Conventional EWMA chart detection occurred a median of 7 months prior to outbreak onset and 14 months prior to traditional detection. Modified Shewhart and EWMA charts additionally detected several outbreaks earlier than conventional SPC charts. Shewhart and SPC charts had low false-positive rates when used to analyse separate control hospital SSI data. Our findings illustrate the potential usefulness and feasibility of real-time SPC surveillance of SSI to rapidly identify outbreaks and improve patient safety. Further study is needed to optimise SPC chart selection and calculation, statistical outbreak detection rules and the process for reacting to signals of potential outbreaks. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Smartphone-based rapid quantification of viable bacteria by single-cell microdroplet turbidity imaging.

PubMed

Cui, Xiaonan; Ren, Lihui; Shan, Yufei; Wang, Xixian; Yang, Zhenlong; Li, Chunyu; Xu, Jian; Ma, Bo

2018-05-18

Standard plate count (SPC) has been recognized as the golden standard for the quantification of viable bacteria. However, SPC usually takes one to several days to grow individual cells into a visible colony, which greatly hampers its application in rapid bacteria enumeration. Here we present a microdroplet turbidity imaging based digital standard plate count (dSPC) method to overcome this hurdle. Instead of cultivating on agar plates, bacteria are encapsulated in monodisperse microdroplets for single-cell cultivation. Proliferation of the encapsulated bacterial cell produced a detectable change in microdroplet turbidity, which allowed, after just a few bacterial doubling cycles (i.e., a few hours), enumeration of viable bacteria by visible-light imaging. Furthermore, a dSPC platform integrating a power-free droplet generator with smartphone-based turbidity imaging was established. As proof-of-concept demonstrations, a series of Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Bacillus subtilis) samples were quantified via the smartphone dSPC accurately within 6 hours, representing a detection sensitivity of 100 CFU ml-1 and at least 3 times faster. In addition, Enterobacter sakazakii (E. sakazakii) in infant milk powder as a real sample was enumerated within 6 hours, in contrast to the 24 hours needed in traditional SPC. Results with high accuracy and reproducibility were achieved, with no difference in counts found between dSPC and SPC. By enabling label-free, rapid, portable and low-cost enumeration and cultivation of viable bacteria onsite, smartphone dSPC forms the basis for a temporally and geographically trackable network for surveying live microbes globally where every citizen with a cellphone can contribute anytime and anywhere.

Randomized trial of standard pain control with or without gabapentin for pain related to radiation-induced mucositis in head and neck cancer.

PubMed

Kataoka, Tomoko; Kiyota, Naomi; Shimada, Takanobu; Funakoshi, Yohei; Chayahara, Naoko; Toyoda, Masanori; Fujiwara, Yutaka; Nibu, Ken-Ichi; Komori, Takahide; Sasaki, Ryohei; Mukohara, Toru; Minami, Hironobu

2016-12-01

Radiation-induced mucositis (RIM) in chemoradiotherapy (CRT) for head and neck cancer (HNC) causes severe pain and worsens CRT compliance, QOL and outcome. Following retrospective reports, we conducted a randomized trial of the safety and efficacy of gabapentin for RIM-associated pain during CRT. HNC patients (pts) receiving CRT were randomized to standard pain control (SPC) with acetaminophen and opioids, or SPC plus gabapentin (SPC+G). Gabapentin was maintained at 900mg/day for 4 weeks after CRT. Primary endpoint was maximum visual analogue scale (VAS) score during CRT, and secondary endpoints were total opioid dose, changes in QOL (EORTC QLQ-C30 and QLQ-HN 35) from baseline to 4 weeks after CRT, and adverse events. Twenty-two eligible Stage III or IV pts were randomly assigned to SPC or SPC+G (n=11 each). Twelve were treated in a locally advanced setting and 10 in a postoperative setting. Median maximum VAS scores, median total dose of opioids at maximum VAS and total dose of opioids at 4 weeks after CRT tended to be higher in the SPC+G arm (47 in SPC vs. 74 in SPC+G, p=0.517; 215mg vs. 745.3mg, p=0.880; and 1260mg vs. 1537.5mg, p=0.9438, respectively), without significance. QOL analysis showed significantly worse scores in the SPC+G arm for weight gain (p=0.005). Adverse events related to gabapentin were manageable. This pilot study is the first prospective randomized trial of gabapentin for RIM-related pain. Gabapentin had no apparent beneficial effect. Further research into agents for RIM-related pain is warranted. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Improved pharmacokinetics and reduced toxicity of brucine after encapsulation into stealth liposomes: role of phosphatidylcholine

PubMed Central

Chen, Jun; Yan, Guo-jun; Hu, Rong-rong; Gu, Qian-wen; Chen, Ming-lei; Gu, Wei; Chen, Zhi-peng; Cai, Bao-chang

2012-01-01

Objective: Brucine was encapsulated into stealth liposomes using the ammonium sulfate gradient method to improve therapeutic index. Materials and methods: Four brucine stealth liposomal formulations were prepared, which were made from different phosphatidylcholines (PCs) with different phase transition temperatures (Tm). The PCs used were soy phosphatidylcholine (SPC), dipalmitoyl phosphatidylcholine (DPPC), hydrogenated soy phosphatidylcholine (HSPC), and distearoyl phosphatidylcholine (DSPC). The stabilities, pharmacokinetics, and toxicities of these liposomal formulations were evaluated and compared. Results: Size, zeta potential, and entrapment efficiency of brucine-loaded stealth liposomes (BSL) were not influenced by PC composition. In vitro release studies revealed that drug release rate increased with decreased Tm of PCs, especially with the presence of rat plasma. After intravenous administration, the area under the curve (AUC) values of BSL-SPC, BSL-DPPC, BSL-HSPC, and BSL-DSPC in plasma were 7.71, 9.24, 53.83, and 56.83-fold as large as that of free brucine, respectively. The LD50 values of brucine solution, BSL-SPC, BSL-DPPC, BSL-HSPC, and BSL-DSPC following intravenous injection were 13.17, 37.30, 37.69, 51.18, and 52.86 mg/kg, respectively. It was found in calcein retention experiments that the order of calcein retention in rat plasma was SPC < DPPC << HSPC < DSPC stealth liposomes. Conclusion: PC composition could exert significant influence on the stabilities, pharmacokinetics, and toxicities of brucine-loaded stealth liposomes. DSPC or HSPC with Tm above 50°C should be used to prepare the stealth liposomal formulation for the intravenous delivery of brucine. However, it was found in the present paper that the pharmacokinetics and toxicity of BSL were not influenced by the PC composition when the Tm of the PC was in the range of −20°C to 41°C. PMID:22904620

Nanopattern-guided growth of single-crystal silicon on amorphous substrates and high-performance sub-100 nm thin-film transistors for three-dimensional integrated circuits

NASA Astrophysics Data System (ADS)

Gu, Jian

This thesis explores how nanopatterns can be used to control the growth of single-crystal silicon on amorphous substrates at low temperature, with potential applications on flat panel liquid-crystal display and 3-dimensional (3D) integrated circuits. I first present excimer laser annealing of amorphous silicon (a-Si) nanostructures on thermally oxidized silicon wafer for controlled formation of single-crystal silicon islands. Preferential nucleation at pattern center is observed due to substrate enhanced edge heating. Single-grain silicon is obtained in a 50 nm x 100 nm rectangular pattern by super lateral growth (SLG). Narrow lines (such as 20-nm-wide) can serve as artificial heterogeneous nucleation sites during crystallization of large patterns, which could lead to the formation of single-crystal silicon islands in a controlled fashion. In addition to eximer laser annealing, NanoPAtterning and nickel-induced lateral C&barbelow;rystallization (NanoPAC) of a-Si lines is presented. Single-crystal silicon is achieved by NanoPAC. The line width of a-Si affects the grain structure of crystallized silicon lines significantly. Statistics show that single-crystal silicon is formed for all lines with width between 50 nm to 200 nm. Using in situ transmission electron microscopy (TEM), nickel-induced lateral crystallization (Ni-ILC) of a-Si inside a pattern is revealed; lithography-constrained single seeding (LISS) is proposed to explain the single-crystal formation. Intragrain line and two-dimensional defects are also studied. To test the electrical properties of NanoPAC silicon films, sub-100 nm thin-film transistors (TFTs) are fabricated using Patten-controlled crystallization of Ṯhin a-Si channel layer and H&barbelow;igh temperature (850°C) annealing, coined PaTH process. PaTH TFTs show excellent device performance over traditional solid phase crystallized (SPC) TFTs in terms of threshold voltage, threshold voltage roll-off, leakage current, subthreshold swing, on/off current ratio, device-to-device uniformity etc. Two-dimensional device simulations show that PaTH TFTs are comparable to silicon-on-insulator (SOI) devices, making it a promising candidate for the fabrication of future high performance, low-power 3D integrated circuits. Finally, an ultrafast nanolithography technique, laser-assisted direct imprint (LADI) is introduced. LADI shows the ability of patterning nanostructures directly in silicon in nanoseconds with sub-10 nm resolution. The process has potential applications in multiple disciplines, and could be extended to other materials and processes.

Interactive Video: Meeting the Ford Challenge.

ERIC Educational Resources Information Center

Copeland, Peter

Many companies using Statistical Process Control (SPC) in their manufacturing processes have found that, despite the training difficulties presented by the technique, the rewards of successful SPC include increased productivity, quality, and market leadership. The Ford Motor Company has developed its SPC training with interactive video, which…

Cleaning frequency and the microbial load in ice-cream.

PubMed

Holm, Sonya; Toma, Ramses B; Reiboldt, Wendy; Newcomer, Chris; Calicchia, Melissa

2002-07-01

This study investigates the efficacy of a 62 h cleaning frequency in the manufacturing of ice-cream. Various product and product contact surfaces were sampled progressively throughout the time period between cleaning cycles, and analyzed for microbial growth. The coliform and standard plate counts (SPC) of these samples did not vary significantly over time after 0, 24, 48, or 62 h from Cleaning in Place (CiP). Data for product contact surfaces were significant for the SPC representing sample locations. Some of the variables in cleaning practices had significant influence on microbial loads. An increase in the number of flavors manufactured caused a decrease in SPC within the 24 h interval, but by the 48 h interval the SPC increased. More washouts within the first 24 h interval were favorable, as indicated by decreased SPC. The more frequently the liquefier was sanitized within the 62 h interval, the lower the SPC. This study indicates that food safety was not compromised and safety practices were effectively implemented throughout the process.

SU-F-T-104: Determining the NTCP Parameters of Pharyngeal Constrictors and Proximal Esophagus for Radiation Induced Swallowing Problems Recorded Six Months After Radiation Therapy for Head and Neck Tumors

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

Mavroidis, P; Price, A; Kostich, M

Purpose: To estimate the radiobiological parameters of four NTCP models that describe the dose-response relations of pharyngeal constrictors and proximal esophagus regarding the severity of patient reported swallowing problems 6 months post chemo-radiotherapy. To identify the section/structure that best correlates with the manifestation of the clinical endpoints. Finally, to compare the goodness-of-fit of those models. Methods: Forty-three patients were treated on a prospective multi-institutional phase II study for oropharyngeal squamous cell carcinoma. All the patients received 60 Gy IMRT and they reported symptoms using the novel patient reported outcome version of the CTCAE. We derived the individual patient dosimetric datamore » of superior, medium and inferior sections of pharyngeal constrictors (SPC, MPC and IPC), superior and inferior sections of esophagus (SES and IES) as separate structures as well as combinations. The Lyman-Kutcher-Burman (LKB), Relative Seriality (RS), Logit and Relative Logit (RL) NTCP models were used to fit the patient data. The fitting of the different models was assessed through the area under the receiver operating characteristic curve (AUC) and the Odds Ratio methods. Results: The AUC values were highest for the SPC for Grade ≥ 2 (0.719 for the RS and RL models, and 0.716 for LKB and Logit). For Grade ≥ 1, the respective values were 0.699 for RS, LKB and Logit and 0.676 for RL. For MPC the AUC values varied between 0.463–0.477, for IPC between 0.396–0.458, for SES between 0.556–0.613 and for IES between 0.410–0.519. The Odds Ratio for the SPC was 15.6 (1.7–146.4) for RS, LKB and Logit for NTCP of 55%. Conclusion: All the examined NTCP models could fit the clinical data with similar accuracy. The SPC appear to correlate best with the clinical endpoints of swallowing problems. A prospective study could establish the use of NTCP values of SPC as a constraint in treatment planning.« less

Public Health Information and a Diverse Population.

ERIC Educational Resources Information Center

Perkins, Mark

This paper discusses public health services of the Secretariat of the Pacific Community (SPC). The paper provides an overview of SPC and the Pacific Islands, including geography, nationality/culture, and development status. SPC Community Health Programmes (CHP) in the following areas are then described: environmental health; AIDS and STD (sexually…

Development of Drag Reducing Polymer of FDR-SPC

NASA Astrophysics Data System (ADS)

Lee, Inwon; Park, Hyun; Chun, Ho Hwan

2015-11-01

In this study, a novel FDR-SPC (Frictional Drag Reduction Self-Polishing Copolymer) is first synthesized in this study. The drag reducing functional radical such as PEGMA (Poly(ethylene) glycol methacrylate) has been utilized to participate in the synthesis process of the SPC. The release mechanism of drag reducing radical is accounted for the hydrolysis reaction between the FDR-SPC and seawater. The types of the baseline SPC monomers, the molecular weight and the mole fraction of PEGMA were varied in the synthesis process. The resulting SPCs were coated to the substrate plates for the subsequent hydrodynamic test for skin friction measurement. A significant reduction in Reynolds stress was observed in a range of specimen, with the maximum drag reduction being 15.9% relative to the smooth surface for PRD3-1.

The murine SP-C promoter directs type II cell-specific expression in transgenic mice.

PubMed

Glasser, Stephan W; Eszterhas, Susan K; Detmer, Emily A; Maxfield, Melissa D; Korfhagen, Thomas R

2005-04-01

Genomic DNA from the mouse pulmonary surfactant protein C (SP-C) gene was analyzed in transgenic mice to identify DNA essential for alveolar type II cell-specific expression. SP-C promoter constructs extending either 13 or 4.8 kb upstream of the transcription start site directed lung-specific expression of the bacterial chloramphenicol acetyl transferase (CAT) reporter gene. In situ hybridization analysis demonstrated alveolar cell-specific expression in the lungs of adult transgenic mice, and the pattern of 4.8 SP-C-CAT expression during development paralleled that of the endogenous SP-C gene. With the use of deletion constructs, lung-specific, low-level CAT activity was detected in tissue assays of SP-C-CAT transgenic mice retaining 318 bp of the promoter. In transient and stable cell transfection experiments, the 4.8-kb SP-C promoter was 90-fold more active as a stably integrated gene. These findings indicate that 1) the 4.8-kb SP-C promoter is sufficient to direct cell-specific and developmental expression, 2) an enhancer essential for lung-specific expression maps to the proximal 318-bp promoter, and 3) the activity of the 4.8-kb SP-C promoter construct is highly dependent on its chromatin environment.

Sphingosylphosphorylcholine promotes the differentiation of resident Sca-1 positive cardiac stem cells to cardiomyocytes through lipid raft/JNK/STAT3 and β-catenin signaling pathways.

PubMed

Li, Wenjing; Liu, Honghong; Liu, Pingping; Yin, Deling; Zhang, Shangli; Zhao, Jing

2016-07-01

Resident cardiac Sca-1-positive (+) stem cells may differentiate into cardiomyocytes to improve the function of damaged hearts. However, little is known about the inducers and molecular mechanisms underlying the myogenic conversion of Sca-1(+) stem cells. Here we report that sphingosylphosphorylcholine (SPC), a naturally occurring bioactive lipid, induces the myogenic conversion of Sca-1(+) stem cells, as evidenced by the increased expression of cardiac transcription factors (Nkx2.5 and GATA4), structural proteins (cardiac Troponin T), transcriptional enhancer (Mef2c) and GATA4 nucleus translocation. First, SPC activated JNK and STAT3, and the JNK inhibitor SP600125 or STAT3 inhibitor stattic impaired the SPC-induced expression of cardiac transcription factors and GATA4 nucleus translocation, which suggests that JNK and STAT3 participated in SPC-promoted cardiac differentiation. Moreover, STAT3 activation was inhibited by SP600125, whereas JNK was inhibited by β-cyclodextrin as a lipid raft breaker, which indicates a lipid raft/JNK/STAT3 pathway involved in SPC-induced myogenic transition. β-Catenin, degraded by activated GSK3β, was inhibited by SPC. Furthermore, GSK3β inhibitors weakened but the β-catenin inhibitor promoted SPC-induced differentiation. We found no crosstalk between the lipid raft/JNK/STAT3 and β-catenin pathway. Our study describes a lipid, SPC, as an endogenic inducer of myogenic conversion in Sca-1(+) stem cells with low toxicity and high efficiency for uptake. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of hydrophobic helix length and side chain chemistry on biomimicry in peptoid analogues of SP-C.

PubMed

Brown, Nathan J; Wu, Cindy W; Seurynck-Servoss, Shannon L; Barron, Annelise E

2008-02-12

The hydrophobic proteins of lung surfactant (LS), SP-B and SP-C, are critical constituents of an effective surfactant replacement therapy for the treatment of respiratory distress syndrome. Because of concerns and difficulties associated with animal-derived surfactants, recent investigations have focused on the creation of synthetic analogues of the LS proteins. However, creating an accurate mimic of SP-C that retains its biophysical surface activity is extraordinarily challenging given the lipopeptide's extreme hydrophobicity and propensity to misfold and aggregate. One successful approach that overcomes these difficulties is the use of poly-N-substituted glycines, or peptoids, to mimic SP-C. To develop a non-natural, bioactive mimic of SP-C and to investigate the effects of side chain chemistry and length of the helical hydrophobic region, we synthesized, purified, and performed in vitro testing of two classes of peptoid SP-C mimics: those having a rigid alpha-chiral aromatic helix and those having a biomimetic alpha-chiral aliphatic helix. The length of the two classes of mimics was also systematically altered. Circular dichroism spectroscopy gave evidence that all of the peptoid-based mimics studied here emulated SP-C's secondary structure, forming stable helical structures in solution. Langmuir-Wilhelmy surface balance, fluorescence microscopy, and pulsating bubble surfactometry experiments provide evidence that the aromatic-based SP-C peptoid mimics, in conjunction with a synthetic lipid mixture, have superior surface activity and biomimetic film morphology in comparison to the aliphatic-based mimics and that there is an increase in surface activity corresponding to increasing helical length.

Quality control troubleshooting tools for the mill floor

Treesearch

John Dramm

2000-01-01

Statistical Process Control (SPC) provides effective tools for improving process quality in the forest products industry resulting in reduced costs and improved productivity. Implementing SPC helps identify and locate problems that occur in wood products manufacturing. SPC tools achieve their real value when applied on the mill floor for monitoring and troubleshooting...

Is Thrombus With Subcutaneous Edema Detected by Ultrasonography Related to Short Peripheral Catheter Failure? A Prospective Observational Study.

PubMed

Takahashi, Toshiaki; Murayama, Ryoko; Oe, Makoto; Nakagami, Gojiro; Tanabe, Hidenori; Yabunaka, Koichi; Arai, Rika; Komiyama, Chieko; Uchida, Miho; Sanada, Hiromi

Short peripheral catheter (SPC) failure is an important clinical problem. The purpose of this study was to clarify the relationship between SPC failure and etiologies such as thrombus, subcutaneous edema, and catheter dislodgment using ultrasonography and to explore the risk factors associated with the etiologies. Two hundred catheters that were in use for infusion, excluding chemotherapy, were observed. Risk factors were examined by logistic regression analysis. Sixty catheters were removed as the result of SPC failure. Frequency of thrombus with subcutaneous edema in SPC failure cases was significantly greater than in those cases where therapy was completed without complications (P < .01). Multivariate analysis demonstrated that 2 or more insertion attempts were significantly associated with thrombus with subcutaneous edema. Results suggest that subsurface skin assessment for catheterization could prevent SPC failure.

Sika pilose antler type I collagen promotes BMSC differentiation via the ERK1/2 and p38-MAPK signal pathways.

PubMed

Wang, Yanshuang; Luo, Su; Zhang, Dafang; Qu, Xiaobo; Tan, Yinfeng

2017-12-01

Sika pilose antler type I collagen (SPC-I) have been reported to promote bone marrow mesenchymal stem cell (BMSC) proliferation and differentiation. However, the underlying mechanism is still unclear. This study investigates the molecular mechanisms of SPC-I on the BMSC proliferation and differentiation of osteoblast (OB) in vitro. The primary rat BMSC was cultured and exposed to SPC-I at different concentrations (2.5, 5.0 and 10.0 mg/mL) for 20 days. The effect of SPC-I on the differentiation of BMSCs was evaluated through detecting the activity of alkaline phosphatase (ALP), ALP staining, collagen I (Col-I) content, and calcified nodules. The markers of osteoblastic differentiation were evaluated using RT-PCR and Western-blot analysis. SPC-I treatment (2.5 mg/mL) significantly increased the proliferation of BMSCs (p < 0.01), whereas, SPC-I (5.0 and 10.0 mg/mL) significantly inhibited the proliferation of BMSCs (p < 0.01). SPC-I (2.5 mg/mL) significantly increased ALP activity and Col-I content (p < 0.01), and increased positive cells in ALP staining and the formation of calcified nodules. Additionally, the gene expression of ALP, Col-I, Osteocalcin (OC), Runx2, Osterix (Osx), ERK1/2, BMP2 and p38-MAPK, along with the protein expression of ERK1/2, p-ERK1/2, p-p38 MAPK were markedly increased in the SPC-I (5.0 mg/mL) treatment group (p < 0.01) compared to the control group. SPC-I can induce BMSC differentiation into OBs and enhance the function of osteogenesis through ERK1/2 and p38-MAPK signal transduction pathways and regulating the gene expression of osteogenesis-specific transcription factors.

[Sincerity of effort: isokinetic evaluation of knee extension].

PubMed

Colombo, R; Demaiti, G; Sartorio, F; Orlandini, D; Vercelli, S; Ferriero, G

2008-01-01

The aim of this study was to find a reliable method to evaluate the sincerity of the muscular maximal effort performed in a dynamometric isokinetic test of knee flexion-extension. The coefficient of variation of the peak torque (CV) and 3 new indices were analysed: (1) the average coefficient of variation calculated on the complete peak torque curve (CVM); (2) the slope of the regression line in an endurance test (PRR); (3) the correlation coefficient of the peak torques in the same endurance test (CCR). Twenty healthy subjects underwent assessment in two different trials, maximal (MX) and 50% submaximal (SMX), with 20 minutes of rest between trials. Each trial consisted of 4 tests, each of 3 repetitions, at angular speed of 30, 180, 30, and 180 degrees/s, respectively, and 1 test of 15 repetitions at 240 degrees/s. Our findings confirmed the ability of CV to detect a high percentage of sincere efforts: at 30 degrees/s Sensibility (Sns)=100% and Specificity (Spc)=70%; at 180 degrees/s Sns=75%, Spc=95%. The 3 new indices here proposed showed high characteristics of Sns and Spc, generally better than those of CV. CVM showed at 180 degrees/s Sns=90% and Spc=100%, while at 30 degrees/s Sns=90%, Spc=75%. PRR was the best index identifying all the efforts, except one (Sns=100%, Spc=95%). The CCR coefficient showed Sns and Spc values both of 90%.

Analyses of Small Punch Creep Deformation Behavior of 316LN Stainless Steel Having Different Nitrogen Contents

NASA Astrophysics Data System (ADS)

Ganesh Kumar, J.; Laha, K.; Ganesan, V.; Prasad Reddy, G. V.

2018-05-01

The small punch creep (SPC) behavior of 316LN stainless steel (SS) containing 0.07, 0.11 and 0.14 wt.% nitrogen has been investigated at 923 K. The transient and tertiary SPC deformation of 316LN SS with various nitrogen contents have been analyzed according to the equation proposed for SPC deflection, δ = δ0 + δT (1 - e^{ - κ t} ) + \\dot{δ }s t + δ3 e^{[ φ( {t - tr } )} ]. The relationships among the rate of exhaustion of transient creep ( κ), steady-state deflection rate (\\dot{δ }s) and the rate of acceleration of tertiary creep ( φ) revealed the interrelationships among the three stages of SPC curve. The first-order reaction rate theory was found to be applicable to SPC deformation throughout the transient as well as tertiary region, in all the investigated steels. The initial and final creep deflection rates were decreased, whereas time to attain steady-state deflection rate increased with the increase in nitrogen content. By increasing the nitrogen content in 316LN SS from 0.07 to 0.14 wt.%, each stage of SPC was prolonged, and consequently, the values of κ, \\dot{δ }s and φ were lowered. Using the above parameters, the master curves for both transient and tertiary SPC deflections were constructed for 316LN SS containing different nitrogen contents.

Analyses of Small Punch Creep Deformation Behavior of 316LN Stainless Steel Having Different Nitrogen Contents

NASA Astrophysics Data System (ADS)

Ganesh Kumar, J.; Laha, K.; Ganesan, V.; Prasad Reddy, G. V.

2018-04-01

The small punch creep (SPC) behavior of 316LN stainless steel (SS) containing 0.07, 0.11 and 0.14 wt.% nitrogen has been investigated at 923 K. The transient and tertiary SPC deformation of 316LN SS with various nitrogen contents have been analyzed according to the equation proposed for SPC deflection, δ = δ0 + δT (1 - e^{ - κ t} ) + \\dot{δ }s t + δ3 e^[ φ( t - tr ) ]. The relationships among the rate of exhaustion of transient creep (κ), steady-state deflection rate (\\dot{δ }s ) and the rate of acceleration of tertiary creep (φ) revealed the interrelationships among the three stages of SPC curve. The first-order reaction rate theory was found to be applicable to SPC deformation throughout the transient as well as tertiary region, in all the investigated steels. The initial and final creep deflection rates were decreased, whereas time to attain steady-state deflection rate increased with the increase in nitrogen content. By increasing the nitrogen content in 316LN SS from 0.07 to 0.14 wt.%, each stage of SPC was prolonged, and consequently, the values of κ, \\dot{δ }s and φ were lowered. Using the above parameters, the master curves for both transient and tertiary SPC deflections were constructed for 316LN SS containing different nitrogen contents.

Defective prohormone processing and altered pancreatic islet morphology in mice lacking active SPC2

PubMed Central

Furuta, Machi; Yano, Hideki; Zhou, An; Rouillé, Yves; Holst, Jens J.; Carroll, Raymond; Ravazzola, Mariella; Orci, Lelio; Furuta, Hiroto; Steiner, Donald F.

1997-01-01

The prohormone convertase SPC2 (PC2) participates in the processing of proinsulin, proglucagon, and a variety of other neuroendocrine precursors, acting either alone or in conjunction with the structurally related dense-core granule convertase SPC3 (PC3/PC1). We have generated a strain of mice lacking active SPC2 by introducing the neomycin resistance gene (Neor) into the third exon of the mSPC2 gene. This gene insertion results in the synthesis of an exon 3-deleted form of SPC2 that does not undergo autoactivation and is not secreted. The homozygous mutant mice appear to be normal at birth. However, they exhibit a small decrease in rate of growth. They also have chronic fasting hypoglycemia and a reduced rise in blood glucose levels during an intraperitoneal glucose tolerance test, which is consistent with a deficiency of circulating glucagon. The processing of proglucagon, prosomatostatin, and proinsulin in the alpha, delta, and beta cells, respectively, of the pancreatic islets is severely impaired. The islets in mutant mice at 3 months of age show marked hyperplasia of alpha and delta cells and a relative diminution of beta cells. SPC2-defective mice offer many possibilities for further delineating neuroendocrine precursor processing mechanisms and for exploring more fully the physiological roles of many neuropeptides and peptide hormones. PMID:9192619

[Fever-shivers reaction and standard platelet concentrates transfusion: a prospective study].

PubMed

Houissa, B; Abdelkefi, S; Bouslama, M; Zaeir, M; Chakroun, T; Ghachem, L; Yacoub, S

2003-09-01

Fever-shivers reaction (FSR) is the most frequent transfusion immediate incident related to platelet transfusions. The aim of our prospective study was to assess the frequency of the different immediate incidents, especially the frequency and the causes of the FSR, observed during the transfusion of standard platelet concentrates (SPC). For each FSR, analysis of causes included: a bacterial culture of the implicated SPC, a blood culture and HLA antibody screening (lymphocytotoxicity assay) among the patients. In the study period, 34 patients were followed during 74 transfusions. Ten immediate incidents were noted; FSR: N = 8, erythema-urticaria: N = 1 and nausea-vomit: N = 1. The FSR was observed in 6 patients who received 56 SPC. Analysis of causes of this reaction revealed that: HLA antibodies were present in one patient; bacterial contamination was not found neither among the patients nor in the implicated SPC, and the risk of the FSR occurrence rose with increased storage time of the SPC transfused. Indeed, a significant difference was noted between the mean age of the SPC implicated in the FSR and the mean age of those not implicated (P = 0,0028). In conclusion, the FSR is a frequent incident observed during SPC transfusions. In the majority of cases, the cause of this reaction was not identified. Further studies will be necessary to better understand the physiological mechanisms of the FSR.

Effects of replacing fish meal with soy protein concentrate and of DL-methionine supplementation in high-energy, extruded diets on the growth and nutrient utilization of rainbow trout, Oncorhynchus mykiss.

PubMed

Mambrini, M; Roem, A J; Carvèdi, J P; Lallès, J P; Kaushik, S J

1999-11-01

Our objectives were to test the potential replacement of fish meal by soy protein concentrate (SPC) in high-energy, extruded diets fed to rainbow trout (Oncorhynchus mykiss) and to evaluate the efficiency of DL-methionine supplementation of soy-based diets. Groups of trout (initial BW 103 to 106 g) were fed to visual satiety with isonitrogenous (6.6% DM) high-energy (22.8 MJ/kg DM gross energy), extruded diets, in which fish meal was progressively replaced with SPC (0, 50, 75, and 100%). Three 100% SPC diets were formulated to be either unsupplemented or supplemented with DL-methionine, so that total methionine content was .8 or 1.0% of DM. The quality of the SPC source used was assessed by measuring the antitryptic and antigenic activities and the concentrations of the isoflavones daidzein and genistein. Apparent digestibility of the diets was determined using the indirect method. A growth trial was conducted over 90 d at a water temperature of 18 degrees C. In addition to body composition analysis, plasma amino acid concentrations, anti-soy protein antibodies in the serum, and isoflavone concentrations in the bile were measured. The SPC source tested exhibited low antitryptic and antigenic activities, but it contained high concentrations of isoflavones (1,990 and 5,903 ppm for daidzein and genistein, respectively). Protein digestibility was high (92%) and was unaffected either the proportion of SPC in the diet or by DL-methionine supplementation. This was also true for the availability of amino acids, except phenylalanine. Digestibility of lipid and energy was reduced by 19% when SPC totally replaced fish meal. Growth rate was reduced when more than 50% of the dietary protein was of soy origin (daily growth coefficient of 3.2 and 2.1% for the control and the unsupplemented 100% SPC diet, respectively). The effect on growth was mainly explained by a general decline in feed intake (13.7 and 12.0 g DM x kg BW(-1) x d(-1) for the control and the unsupplemented 100% SPC diet, respectively) and in lipid and, thus, in energy digestibility. The DL-methionine supplementation partially reversed the depressive effects of high dietary SPC incorporation (+13% growth), mainly by enhancing intake. The negative effect of SPC incorporation either may be due to the high isoflavone concentration or to an interaction between the soy protein component and the dietary lipids.

Tumour stage and gender predict recurrence and second primary malignancies in head and neck cancer: a multicentre study within the INHANCE consortium.

PubMed

Leoncini, Emanuele; Vukovic, Vladimir; Cadoni, Gabriella; Giraldi, Luca; Pastorino, Roberta; Arzani, Dario; Petrelli, Livia; Wünsch-Filho, Victor; Toporcov, Tatiana Natasha; Moyses, Raquel Ayub; Matsuo, Keitaro; Bosetti, Cristina; La Vecchia, Carlo; Serraino, Diego; Simonato, Lorenzo; Merletti, Franco; Boffetta, Paolo; Hashibe, Mia; Lee, Yuan-Chin Amy; Boccia, Stefania

2018-05-19

Recurrence and second primary cancer (SPC) continue to represent major obstacles to long-term survival in head and neck cancer (HNC). Our aim was to evaluate whether established demographics, lifestyle-related risk factors for HNC and clinical data are associated with recurrence and SPC in HNC. We conducted a multicentre study by using data from five studies members of the International Head and Neck Cancer Epidemiology consortium-Milan, Rome, Western Europe, Sao Paulo, and Japan, totalling 4005 HNC cases with a median age of 59 (interquartile range 52-67). Multivariate hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated for recurrence and SPC. During follow-up, 1161 (29%) patients had recurrence and 343 (8.6%) developed SPC. Advanced tumour stage was associated with increased risk of recurrence in HNC overall (HR = 1.76, 95% CI 1.41-2.19). Women with laryngeal cancer had a reduced risk of recurrence compared to men (HR = 0.39, 95% CI: 0.24-0.74). Concerning predictors of SPC, advanced age (HR = 1.02; 95% CI: 1.00-1.04) and alcohol consumption (> 1 drink per day, HR = 2.11; 95% CI: 1.13-3.94) increased the risk of SPC among patients with laryngeal cancer. Additionally, women were at higher risk of SPC, in HNC overall group (HR = 1.68; 95% CI: 1.13-2.51) and oropharyngeal cancer group (HR = 1.74; 95% CI: 1.02-2.98). Tumour stage and male gender (larynx only) were positive predictors of cancer recurrence in HNC patients. Predictors of SPC were advanced age and alcohol use among laryngeal cancer cases, and female gender for oropharyngeal and HNC overall.

Cobalt Chloride Upregulates Impaired HIF-1α Expression to Restore Sevoflurane Post-conditioning-Dependent Myocardial Protection in Diabetic Rats.

PubMed

Wu, Jianjiang; Yang, Long; Xie, Peng; Yu, Jin; Yu, Tian; Wang, Haiying; Maimaitili, Yiliyaer; Wang, Jiang; Ma, Haiping; Yang, Yining; Zheng, Hong

2017-01-01

Previous studies from our group have demonstrated that sevoflurane post-conditioning (SPC) protects against myocardial ischemia reperfusion injury via elevating the intranuclear expression of hypoxia inducible factor-1 alpha (HIF-1α). However, diabetic SPC is associated with decreased myocardial protection and disruption of the HIF-1 signaling pathway. Previous studies have demonstrated that cobalt chloride (CoCl 2 ) can upregulate HIF-1α expression under diabetic conditions, but whether myocardial protection by SPC can be restored afterward remains unclear. We established a rat model of type 2 diabetes and a Langendorff isolated heart model of ischemia-reperfusion injury. Prior to reperfusion, 2.4% sevoflurane was used as a post-conditioning treatment. The diabetic rats were treated with CoCl 2 24 h before the experiment. At the end of reperfusion, tests were performed to assess myocardial function, infarct size, mitochondrial morphology, nitric oxide (NO), Mitochondrial reactive oxygen species (ROS), mitochondrial respiratory function and enzyme activity, HIF-1α, vascular endothelial growth factor (VEGF) and endothelial NO synthase (eNOS) protein levels. In addition, myocardial protection by SPC was monitored after the blood glucose levels were lowered by insulin. The diabetic state was associated with deficient SPC protection and decreased HIF-1α expression. After treating the diabetic rats with CoCl 2 , SPC significantly upregulated the expression of HIF-1α, VEGF and eNOS, which markedly improved cardiac function, NO, mitochondrial respiratory function, and enzyme activity and decreased the infarction areas and ROS. In addition, these effects were not influenced by blood glucose levels. This study proved that CoCl 2 activates the HIF-1α signaling pathway, which restores SPC-dependent myocardial protection under diabetic conditions, and the protective effects of SPC were independent of blood glucose levels.

Formation of highly structured cubic micellar lipid nanoparticles of soy phosphatidylcholine and glycerol dioleate and their degradation by triacylglycerol lipase.

PubMed

Wadsäter, Maria; Barauskas, Justas; Nylander, Tommy; Tiberg, Fredrik

2014-05-28

Lipid nanoparticles of reversed internal phase structures, such as cubic micellar (I2) structure show good drug loading ability of peptides and proteins as well as some small molecules. Due to their controllable small size and inner morphology, such nanoparticles are suitable for drug delivery using several different administration routes, including intravenous, intramuscular, and subcutaneous injection. A very interesting system in this regard, is the two component soy phosphatidylcholine (SPC)/glycerol dioleate (GDO) system, which depending on the ratio of the lipid components form a range of reversed liquid crystalline phases. For a 50/50 (w/w) ratio in excess water, these lipids have been shown to form a reversed cubic micellar (I2) phase of the Fd3m structure. Here, we demonstrate that this SPC/GDO phase, in the presence of small quantities (5-10 wt %) of Polysorbate 80 (P80), can be dispersed into nanoparticles, still with well-defined Fd3m structure. The resulting nanoparticle dispersion has a narrow size distribution and exhibit good long-term stability. In pharmaceutical applications, biodegradation pathways of the drug delivery vehicles and their components are important considerations. In the second part of the study we show how the structure of the particles evolves during exposure to a triacylglycerol lipase (TGL) under physiological-like temperature and pH. TGL catalyzes the lipolytic degradation of acylglycerides, such as GDO, to monoglycerides, glycerol, and free fatty acids. During the degradation, the interior phase of the particles is shown to undergo continuous phase transitions from the reversed I2 structure to structures of less negative curvature (2D hexagonal, bicontinuous cubic, and sponge), ultimately resulting in the formation of multilamellar vesicles.

An adverse event of suprapubic catheter SPC insertion. A call for updating the existing guidelines.

PubMed

Jalil, Rozh; Mukundan, Chandrika; Bhatti, Tahir S

2012-11-15

The suprapubic catheter (SPC) is a useful and widely used tool in urological practice. However, complications can arise from its insertion or ongoing care. We add to the literature a case of an adverse event of its insertion where it has gone through a vascular graft and recommending updating the SPC insertion guidelines.

Fieldcrest Cannon, Inc. Advanced Technical Preparation. Statistical Process Control (SPC). PRE-SPC 11: SPC & Graphs. Instructor Book.

ERIC Educational Resources Information Center

Averitt, Sallie D.

This instructor guide, which was developed for use in a manufacturing firm's advanced technical preparation program, contains the materials required to present a learning module that is designed to prepare trainees for the program's statistical process control module by improving their basic math skills in working with line graphs and teaching…

Transcriptional elements from the human SP-C gene direct expression in the primordial respiratory epithelium of transgenic mice.

PubMed

Wert, S E; Glasser, S W; Korfhagen, T R; Whitsett, J A

1993-04-01

Transgenic animals bearing a chimeric gene containing 5'-flanking regions of the human surfactant protein C (SP-C) gene ligated to the bacterial chloramphenicol acetyltransferase (CAT) gene were analyzed by in situ hybridization histochemistry to determine the temporal and spatial distribution of transgene expression during organogenesis of the murine lung. Ontogenic expression of the SP-C-CAT gene was compared to that of the endogenous SP-C gene and to the Clara cell CC10 gene. High levels of SP-C-CAT expression were observed as early as Day 10 of gestation in epithelial cells of the primordial lung buds. Low levels of endogenous SP-C mRNA were detected a day later, but only in the more distal epithelial cells of the newly formed, primitive, lobar bronchi. On Gestational Days 13 through 16, transcripts for both the endogenous and chimeric gene were restricted to distal epithelial elements of the branching bronchial tubules and were no longer detected in the more proximal regions of the bronchial tree. Although high levels of SP-C-CAT expression were maintained throughout organogenesis, endogenous SP-C expression increased dramatically on Gestational Day 15, coincident with acinar tubule differentiation at the lung periphery. Low levels of endogenous CC10 expression were detected by Gestational Day 16 in both lobar and segmental bronchi. By the time of birth, CC10 transcripts were expressed at high levels in the trachea and at all levels of the bronchial tree; endogenous SP-C mRNA was restricted to epithelial cells of the terminal alveolar saccules; and SP-C-CAT expression was now detected in both alveolar and bronchiolar epithelial cells. These results indicate that (1) cis-acting regulatory elements of the human SP-C gene can direct high levels of foreign gene expression to epithelial cells of the embryonic mouse lung; (2) expression of the human SP-C-CAT chimeric gene is developmentally regulated, exhibiting a morphogenic expression pattern similar, but not identical, to that of the endogenous murine SP-C gene; (3) the embryonic expression of endogenous SP-C and chimeric SP-C-CAT transcripts identifies progenitor cells of the distal respiratory epithelium; and (4) differentiation of bronchial epithelium is coincident with loss of SP-C expression and subsequent acquisition of CC10 expression in proximal regions of the developing bronchial tubules.

Limitations of on-site dairy farm regulatory debits as milk quality predictors.

PubMed

Borneman, Darand L; Stiegert, Kyle; Ingham, Steve

2015-03-01

In the United States, compliance with grade A raw fluid milk regulatory standards is assessed via laboratory milk quality testing and by on-site inspection of producers (farms). This study evaluated the correlation between on-site survey debits being marked and somatic cell count (SCC) or standard plate count (SPC) laboratory results for 1,301 Wisconsin grade A dairy farms in 2012. Debits recorded on the survey form were tested as predictors of laboratory results utilizing ordinary least squares regression to determine if results of the current method for on-site evaluation of grade A dairy farms accurately predict SCC and SPC test results. Such a correlation may indicate that current methods of on-site inspection serve the primary intended purpose of assuring availability of high-quality milk. A model for predicting SCC was estimated using ordinary least squares regression methods. Step-wise selected regressors of grouped debit items were able to predict SCC levels with some degree of accuracy (adjusted R2=0.1432). Specific debit items, seasonality, and farm size were the best predictors of SCC levels. The SPC data presented an analytical challenge because over 75% of the SPC observations were at or below a 25,000 cfu/mL threshold but were recorded by testing laboratories as at the threshold value. This classic censoring problem necessitated the use of a Tobit regression approach. Even with this approach, prediction of SPC values based on on-site survey criteria was much less successful (adjusted R2=0.034) and provided little support for the on-site survey system as a way to inform farmers about making improvements that would improve SPC. The lower level of correlation with SPC may indicate that factors affecting SPC are more varied and differ from those affecting SCC. Further, unobserved deficiencies in postmilking handling and storage sanitation could enhance bacterial growth and increase SPC, whereas postmilking sanitation will have no effect on SCC because somatic cells do not reproduce in stored milk. Results suggest that close examination, and perhaps redefinition, of survey debits, along with making the survey coincident with SCC and SPC sampling, could make the on-site survey a better tool for ensuring availability of high-quality milk. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Origin and enhancement of spin polarized current in diluted magnetic oxides by oxygen vacancies

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

Chou, Hsiung, E-mail: hchou@mail.nsysu.edu.tw; Yang, Kung-Shang; Tsao, Yao-Chung

Spin polarized current (SPC) is a crucial characteristic of diluted magnetic oxides due to the potential application of oxides in spintronic devices. However, most research has been focused on ferromagnetic properties rather than polarization of electric current, because direct measurements are difficult and the origin of SPC has yet to be fully understood. The method to increase the SPC percentage is beyond practical consideration at present. To address this problem, we focus on the role of oxygen vacancies (V{sub O}) on SPC, which are controlled by growing the Co-doped ZnO thin-films at room temperature in a reducing atmosphere [Ar + (1%–30%)H{sub 2}].more » We found that the conductivity increases with an increase of V{sub O} via two independent channels: the variable range hopping (VRH) within localized states and the itinerant transport in the conduction band. The point contact Andreev reflection measurements at 4.2 K, where the electric conduction is governed only by the VRH mechanism, prove that the current flowing in the VRH hopping channel is SPC. The percentage of SPC increases with the introduction of V{sub O} and increase in its concentration. The transport measurement shows that by manipulating V{sub O}, one can control the percentage of VRH hopping conduction such that it can even dominate room temperature conduction. The highest achieved SPC ratio at room temperature was 80%.« less

Comparison of endpoints relevant to toxicity assessments in 3 generations of CD-1 mice fed irradiated natural and purified ingredient diets with varying soy protein and isoflavone contents.

PubMed

Camacho, Luísa; Lewis, Sherry M; Vanlandingham, Michelle M; Juliar, Beth E; Olson, Greg R; Patton, Ralph E; Gamboa da Costa, Gonçalo; Woodling, Kellie; Sepehr, Estatira; Bryant, Matthew S; Doerge, Daniel R; Basavarajappa, Mallikarjuna S; Felton, Robert P; Delclos, K Barry

2016-08-01

Diet is an important variable in toxicology. There are mixed reports on the impact of soy components on energy utilization, fat deposition, and reproductive parameters. Three generations of CD-1 mice were fed irradiated natural ingredient diets with varying levels of soy (NIH-41, 5K96, or 5008/5001), purified irradiated AIN-93 diet, or the AIN-93 formulation modified with ethanol-washed soy protein concentrate (SPC) or SPC with isoflavones (SPC-IF). NIH-41 was the control for pairwise comparisons. Minimal differences were observed among natural ingredient diet groups. F0 males fed AIN-93, SPC, and SPC-IF diets had elevated glucose levels and lower insulin levels compared with the NIH-41 group. In both sexes of the F1 and F2 generations, the SPC and SPC-IF groups had lower body weight gains than the NIH-41 controls and the AIN-93 group had an increased percent body fat at postnatal day 21. AIN-93 F1 pups had higher baseline glucose than NIH-41 controls, but diet did not significantly affect breeding performance or responses to glucose or uterotrophic challenges. Reduced testes weight and sperm in the AIN-93 group may be related to low thiamine levels. Our observations underline the importance of careful selection, manufacturing procedures, and nutritional characterization of diets used in toxicological studies. Published by Elsevier Ltd.

Errors in patient specimen collection: application of statistical process control.

PubMed

Dzik, Walter Sunny; Beckman, Neil; Selleng, Kathleen; Heddle, Nancy; Szczepiorkowski, Zbigniew; Wendel, Silvano; Murphy, Michael

2008-10-01

Errors in the collection and labeling of blood samples for pretransfusion testing increase the risk of transfusion-associated patient morbidity and mortality. Statistical process control (SPC) is a recognized method to monitor the performance of a critical process. An easy-to-use SPC method was tested to determine its feasibility as a tool for monitoring quality in transfusion medicine. SPC control charts were adapted to a spreadsheet presentation. Data tabulating the frequency of mislabeled and miscollected blood samples from 10 hospitals in five countries from 2004 to 2006 were used to demonstrate the method. Control charts were produced to monitor process stability. The participating hospitals found the SPC spreadsheet very suitable to monitor the performance of the sample labeling and collection and applied SPC charts to suit their specific needs. One hospital monitored subcategories of sample error in detail. A large hospital monitored the number of wrong-blood-in-tube (WBIT) events. Four smaller-sized facilities, each following the same policy for sample collection, combined their data on WBIT samples into a single control chart. One hospital used the control chart to monitor the effect of an educational intervention. A simple SPC method is described that can monitor the process of sample collection and labeling in any hospital. SPC could be applied to other critical steps in the transfusion processes as a tool for biovigilance and could be used to develop regional or national performance standards for pretransfusion sample collection. A link is provided to download the spreadsheet for free.

Comparison of endpoints relevant to toxicity assessments in 3 generations of CD-1 mice fed irradiated natural and purified ingredient diets with varying soy protein and isoflavone contents

PubMed Central

Camacho, Luísa; Lewis, Sherry M.; Vanlandingham, Michelle M.; Juliar, Beth E.; Olson, Greg R.; Patton, Ralph E.; da Costa, Gonçalo Gamboa; Woodling, Kellie; Sepehr, Estatira; Bryant, Matthew S.; Doerge, Daniel R.; Basavarajappa, Mallikarjuna S.; Felton, Robert P.; Delclos, K. Barry

2016-01-01

Diet is an important variable in toxicology. There are mixed reports on the impact of soy components on energy utilization, fat deposition, and reproductive parameters. Three generations of CD-1 mice were fed irradiated natural ingredient diets with varying levels of soy (NIH-41, 5K96, or 5008/5001), purified irradiated AIN-93 diet, or the AIN-93 formulation modified with ethanol-washed soy protein concentrate (SPC) or SPC with isoflavones (SPC-IF). NIH-41 was the control for pairwise comparisons. Minimal differences were observed among natural ingredient diet groups. F0 males fed AIN-93, SPC, and SPC-IF diets had elevated glucose levels and lower insulin levels compared with the NIH-41 group. In both sexes of the F1 and F2 generations, the SPC and SPC-IF groups had lower body weight gains than the NIH-41 controls and the AIN-93 group had an increased percent body fat at postnatal day 21. AIN-93 F1 pups had higher baseline glucose than NIH-41 controls, but diet did not significantly affect breeding performance or responses to glucose or uterotrophic challenges. Reduced testes weight and sperm in the AIN-93 group may be related to low thiamine levels. Our observations underline the importance of careful selection, manufacturing procedures, and nutritional characterization of diets used in toxicological studies. PMID:27234134

Cascaded systems analysis of charge sharing in cadmium telluride photon-counting x-ray detectors.

PubMed

Tanguay, Jesse; Cunningham, Ian A

2018-05-01

Single-photon-counting (SPC) and spectroscopic x-ray detectors are under development in academic and industry laboratories for medical imaging applications. The spatial resolution of SPC and spectroscopic x-ray detectors is an important design criterion. The purpose of this article was to extend the cascaded systems approach to include a description of the spatial resolution of SPC and spectroscopic x-ray imaging detectors. A cascaded systems approach was used to model reabsorption of characteristic x rays, Coulomb repulsion, and diffusion in SPC and spectroscopic x-ray detectors. In addition to reabsorption, diffusion, and Coulomb repulsion, the model accounted for x-ray conversion to electron-hole (e-h) pairs, integration of e-h pairs in detector elements, electronic noise, and energy thresholding. The probability density function (PDF) describing the number of e-h pairs was propagated through each stage of the model and was used to derive new theoretical expressions for the large-area gain and modulation transfer function (MTF) of CdTe SPC x-ray detectors, and the energy bin sensitivity functions and MTFs of CdTe spectroscopic detectors. Theoretical predictions were compared with the results of MATLAB-based Monte Carlo (MC) simulations and published data. Comparisons were also made with the MTF of energy-integrating systems. Under general radiographic conditions, reabsorption, diffusion, and Coulomb repulsion together artificially inflate count rates by 20% to 50%. For thicker converters (e.g. 1000 μm) and larger detector elements (e.g. 500 μm pixel pitch) these processes result in modest inflation (i.e. ∼10%) in apparent count rates. Our theoretical and MC analyses predict that SPC MTFs will be degraded relative to those of energy-integrating systems for fluoroscopic, general radiographic, and CT imaging conditions. In most cases, this degradation is modest (i.e., ∼10% at the Nyquist frequency). However, for thicker converters, the SPC MTF can be degraded by up to 25% at the Nyquist frequency relative to EI systems. Additionally, unlike EI systems, the MTF of spectroscopic systems is strongly dependent on photon energy, which results in energy-bin-dependent spatial resolution in spectroscopic systems. The PDF-transfer approach to modeling signal transfer through SPC and spectroscopic x-ray imaging systems provides a framework for understanding system performance. Application of this approach demonstrated that charge sharing artificially inflates the SPC image signal and degrades the MTF of SPC and spectroscopic systems relative to energy-integrating systems. These results further motivate the need for anticharge-sharing circuits to mitigate the effects of charge sharing on SPC and spectroscopic x-ray image quality. © 2018 American Association of Physicists in Medicine.

Biomimicry of surfactant protein C

PubMed Central

Brown, Nathan J.; Johansson, Jan; Barron, Annelise E.

2012-01-01

CONSPECTUS Since the widespread use of exogenous lung surfactant to treat neonatal respiratory distress syndrome, premature infant survival and respiratory morbidity have dramatically improved. Despite the effectiveness of the animal-derived surfactant preparations, there still remain some concerns and difficulties associated with their use. This has prompted investigation into the creation of synthetic surfactant preparations. However, to date, no clinically used synthetic formulation is as effective as the natural material. This is largely because the previous synthetic formulations lacked analogues of the hydrophobic proteins of the lung surfactant system, SP-B and SP-C, which are critical functional constituents. As a result, recent investigation has turned towards the development of a new generation of synthetic, biomimetic surfactants that contain synthetic phospholipids along with a mimic of the hydrophobic protein portion of lung surfactant. In this Account, we detail our efforts in creating accurate mimics of SP-C for use in a synthetic surfactant replacement therapy. Despite SP-C’s seemingly simple structure, the predominantly helical protein is extraordinarily challenging to work with given its extreme hydrophobicity and structural instability, which greatly complicates the creation of an effective SP-C analogue. Drawing inspiration from Nature, two promising biomimetic approaches have led to the creation of rationally designed biopolymers that recapitulate many of SP-C’s molecular features. The first approach utilizes detailed SP-C structure-activity relationships and amino acid folding propensities to create a peptide-based analogue, SP-C33. In SP-C33, the problematic and metastable poly-valine helix is replaced with a structurally stable, poly-leucine helix and includes a well placed positive charge to prevent aggregation. SP-C33 is both structurally stable and eliminates the association propensity of the native protein. The second approach follows the same design considerations, but makes use of a non-natural, poly-N-substituted glycine or “peptoid” scaffold to circumvent the difficulties associated with SP-C. By incorporating unique, biomimetic side chains in a non-natural backbone, the peptoid mimic captures both SP-C’s hydrophobic patterning and helical secondary structure. Despite the differences in structure, both SP-C33 and the SP-C peptoid mimic capture many requisite features of SP-C. In a surfactant environment, these analogues also replicate many of the key surface activities necessary for a functional biomimetic surfactant therapy while overcoming the difficulties associated with the natural protein. With improved stability, greater production potential, and elimination of possible pathogenic contamination, these biomimetic surfactant formulations offer the potential not only to improve the treatment of respiratory distress syndrome, but also the opportunity to treat other respiratory-related disorders. PMID:18834153

On the single-photon-counting (SPC) modes of imaging using an XFEL source

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

Wang, Zhehui

In this study, the requirements to achieve high detection efficiency (above 50%) and gigahertz (GHz) frame rate for the proposed 42-keV X-ray free-electron laser (XFEL) at Los Alamos are summarized. Direct detection scenarios using C (diamond), Si, Ge and GaAs semiconductor sensors are analyzed. Single-photon counting (SPC) mode and weak SPC mode using Si can potentially meet the efficiency and frame rate requirements and be useful to both photoelectric absorption and Compton physics as the photon energy increases. Multilayer three-dimensional (3D) detector architecture, as a possible means to realize SPC modes, is compared with the widely used two-dimensional (2D) hybridmore » planar electrode structure and 3D deeply entrenched electrode architecture. Demonstration of thin film cameras less than 100-μm thick with onboard thin ASICs could be an initial step to realize multilayer 3D detectors and SPC modes for XFELs.« less

On the single-photon-counting (SPC) modes of imaging using an XFEL source

DOE PAGES

Wang, Zhehui

2015-12-14

In this study, the requirements to achieve high detection efficiency (above 50%) and gigahertz (GHz) frame rate for the proposed 42-keV X-ray free-electron laser (XFEL) at Los Alamos are summarized. Direct detection scenarios using C (diamond), Si, Ge and GaAs semiconductor sensors are analyzed. Single-photon counting (SPC) mode and weak SPC mode using Si can potentially meet the efficiency and frame rate requirements and be useful to both photoelectric absorption and Compton physics as the photon energy increases. Multilayer three-dimensional (3D) detector architecture, as a possible means to realize SPC modes, is compared with the widely used two-dimensional (2D) hybridmore » planar electrode structure and 3D deeply entrenched electrode architecture. Demonstration of thin film cameras less than 100-μm thick with onboard thin ASICs could be an initial step to realize multilayer 3D detectors and SPC modes for XFELs.« less

[Effects of sika pilose antler type collagen on ROS1728 cell and its molecular mechanism].

PubMed

Wang, Yan-Shuang; Luo, Su; Zhang, Da-Fang; Qu, Xiao-Bo; Li, Feng

2016-09-01

In this paper, effect and molecular mechanism of sika pilose antler type I collagen(SPC-I) of ROS1728 cell were explored. For the SPC-I provides the theory basis for the treatment of osteoporosis. The adherent method was used to cultivate rat osteosarcoma osteogenesis sample cell line ROS1728. The effect of SPC-I on ROS1728 cells proliferation was tested by CCK-8 method. Runx2, osernix, ALP, Coll-I, OC osteogenesis related genes expression was tested by RT-PCR, and Runx2 protein expression was tested by Western-bolt. Results showed that 5 g•L ⁻¹ SPC-I could inhibit ROS1728 cell proliferation, and significantly promote the expression of ROS1728 cell specific transcription factor Runx2 and osterix mRNA, Runx2 protein and marker gene ALP, Coll-I, OC mRNA expression(P<0.01). 2.5 g•L ⁻¹ and 10 g•L ⁻¹ SPC-I could significantly inhibit the ROS1728 cell proliferation(P<0.01), and inhibit the expression of related genes. In conclusion, 5 g•L ⁻¹ SPC-I could inhibit ROS1728 cell proliferation, obviously enhance ROS1728 cell function, promote ROS1728 cell differentiation, maturation. Copyright© by the Chinese Pharmaceutical Association.

Ectopic expression of plasma membrane targeted subunits of the Ndc80-complex as a tool to study kinetochore biochemistry.

PubMed

Holmström, Tim H; Rehnberg, Jonathan; Ahonen, Leena J; Kallio, Marko J

2009-06-01

Genomic stability depends on the normal function of the kinetochore, a multi-protein assemblage, which consists of over 80 molecules including both constitutive and transiently binding components. Information regarding the spatial-temporal assembly of kinetochore subcomplexes is often limited by technical difficulties in their isolation. To study kinetochore subcomplex formation, we targeted separately Hec1 and Spc24, two subunits of the Ndc80 kinetochore compilation, to the plasma membrane by fusing them with the amino-terminal palmitoylation and myristoylation (pm) sequence of the receptor tyrosine kinase Fyn. We found that in early mitotic cells, pm-GFP-Hec1 and pm-GFP-Spc24 fusion proteins localised to the plasma membrane and were able to recruit all subunits of the Ndc80 complex (Ndc80/Hec1, Nuf2, Spc24 and Spc25) to these foci. In interphase cells, only Hec1-Nuf2 and Spc24-Spc25 heterodimers accumulated to the plasma membrane foci. The results propose that the assembly of Ndc80 tetramer can take place outside of the kinetochore but requires co-factors that are only present in mitotic cells. These findings provide the first experimental evidence on the successful employment of the plasma membrane targeting technique in the study of kinetochore biochemistry.

Two-phase thermodynamic model for efficient and accurate absolute entropy of water from molecular dynamics simulations.

PubMed

Lin, Shiang-Tai; Maiti, Prabal K; Goddard, William A

2010-06-24

Presented here is the two-phase thermodynamic (2PT) model for the calculation of energy and entropy of molecular fluids from the trajectory of molecular dynamics (MD) simulations. In this method, the density of state (DoS) functions (including the normal modes of translation, rotation, and intramolecular vibration motions) are determined from the Fourier transform of the corresponding velocity autocorrelation functions. A fluidicity parameter (f), extracted from the thermodynamic state of the system derived from the same MD, is used to partition the translation and rotation modes into a diffusive, gas-like component (with 3Nf degrees of freedom) and a nondiffusive, solid-like component. The thermodynamic properties, including the absolute value of entropy, are then obtained by applying quantum statistics to the solid component and applying hard sphere/rigid rotor thermodynamics to the gas component. The 2PT method produces exact thermodynamic properties of the system in two limiting states: the nondiffusive solid state (where the fluidicity is zero) and the ideal gas state (where the fluidicity becomes unity). We examine the 2PT entropy for various water models (F3C, SPC, SPC/E, TIP3P, and TIP4P-Ew) at ambient conditions and find good agreement with literature results obtained based on other simulation techniques. We also validate the entropy of water in the liquid and vapor phases along the vapor-liquid equilibrium curve from the triple point to the critical point. We show that this method produces converged liquid phase entropy in tens of picoseconds, making it an efficient means for extracting thermodynamic properties from MD simulations.

Effects of pH, temperature, and chemical structure on the stability of S-(purin-6-yl)-L-cysteine: evidence for a novel molecular rearrangement mechanism to yield N-(purin-6-yl)-L-cysteine.

PubMed

Elfarra, A A; Hwang, I Y

1996-01-01

The stability of S-(purin-6-yl)-L-cysteine (SPC), a kidney-selective prodrug of 6-mercaptopurine and a putative metabolite of 6-chloropurine, was investigated under various pH and temperature conditions. At room temperature, the half-life (t 1/2) of SPC at either highly acidic (pH 3.6) or basic conditions (pH 9.6) was longer than at neutral or slightly acidic or basic conditions (pH 5.7-8.75). The primary degradation product, N-(purin-6-yl)-L-cysteine (NPC), was isolated using Sephadex LH-20 chromatography and characterized by 1H NMR and FAB/MS after derivatization with 2-iodoacetic acid. These results reveal novel stability requirements and implicate the cysteinyl amino group and the purinyl N-1 nitrogen in the mechanism of SPC rearrangement to NPC. Further evidence for this hypothesis was provided by the findings that the stability of SPC in phosphate buffer (pH 7.4) at 37 degrees C was similar to that of S-(guanin-6-yl)-L-cysteine, whereas S-(purin-6-yl)-N-acetyl-L-cysteine and S-(purin-6-yl)glutathione which have their cysteine amino groups blocked were much more stable than SPC. S-(Purin-6-yl)-L-homocysteine (SPHC) was also more stable than SPC, possibly because the formation of a 6-membered ring transition state as would be expected with SPHC is kinetically less favored than the formation of a 5-membered ring transition state as would be expected with SPC. These results may explain previous in vivo metabolism results of SPC and its analogs and may contribute to a better understanding of stability of structurally related cysteine S-conjugates.

Cobalt Chloride Upregulates Impaired HIF-1α Expression to Restore Sevoflurane Post-conditioning-Dependent Myocardial Protection in Diabetic Rats

PubMed Central

Wu, Jianjiang; Yang, Long; Xie, Peng; Yu, Jin; Yu, Tian; Wang, Haiying; Maimaitili, Yiliyaer; Wang, Jiang; Ma, Haiping; Yang, Yining; Zheng, Hong

2017-01-01

Previous studies from our group have demonstrated that sevoflurane post-conditioning (SPC) protects against myocardial ischemia reperfusion injury via elevating the intranuclear expression of hypoxia inducible factor-1 alpha (HIF-1α). However, diabetic SPC is associated with decreased myocardial protection and disruption of the HIF-1 signaling pathway. Previous studies have demonstrated that cobalt chloride (CoCl2) can upregulate HIF-1α expression under diabetic conditions, but whether myocardial protection by SPC can be restored afterward remains unclear. We established a rat model of type 2 diabetes and a Langendorff isolated heart model of ischemia-reperfusion injury. Prior to reperfusion, 2.4% sevoflurane was used as a post-conditioning treatment. The diabetic rats were treated with CoCl2 24 h before the experiment. At the end of reperfusion, tests were performed to assess myocardial function, infarct size, mitochondrial morphology, nitric oxide (NO), Mitochondrial reactive oxygen species (ROS), mitochondrial respiratory function and enzyme activity, HIF-1α, vascular endothelial growth factor (VEGF) and endothelial NO synthase (eNOS) protein levels. In addition, myocardial protection by SPC was monitored after the blood glucose levels were lowered by insulin. The diabetic state was associated with deficient SPC protection and decreased HIF-1α expression. After treating the diabetic rats with CoCl2, SPC significantly upregulated the expression of HIF-1α, VEGF and eNOS, which markedly improved cardiac function, NO, mitochondrial respiratory function, and enzyme activity and decreased the infarction areas and ROS. In addition, these effects were not influenced by blood glucose levels. This study proved that CoCl2activates the HIF-1α signaling pathway, which restores SPC-dependent myocardial protection under diabetic conditions, and the protective effects of SPC were independent of blood glucose levels. PMID:28659817

A clip domain serine protease regulates the expression of proPO and hemolymph clotting in mud crab, Scylla paramamosain.

PubMed

Zhang, Daimeng; Wan, Weisong; Kong, Tongtong; Zhang, Ming; Aweya, Jude Juventus; Gong, Yi; Li, Shengkang

2018-05-07

The clip domain serine proteinases (clip-SPs) play vital roles in embryonic development and in various innate immune functions in invertebrates such as antimicrobial activity, cell adhesion, hemolymph clotting, pattern recognition and regulation of the prophenoloxidase system. However, little is known about the role of the clip domain serine proteinase in Scylla paramamosain (designated SpcSP) immunity. In the present study, we cloned a clip-SP from S. paramamosain hemocytes using rapid amplification of cDNA end (RACE) approach. The full-length cDNA of SpcSP was 1823 bp, containing a 5' untranslated region (UTR) of 334 bp, an open reading frame of 1122 bp, and a 3' UTR of 367 bp. The open reading frame encoded a polypeptide of 373 amino acids with a calculated molecular weight of 39.7 kDa and an isoelectric point of 6.64. Structurally, SpcSP has a predicted 21-residue signal peptide and possessed the characteristic features of the clip domain family of serine proteases, namely one clip domain in the amino-terminal with six highly conserved cysteine residues and one enzyme active serine proteinase domain in the carboxyl-terminal with a highly conserved catalytic triad (His 156 , Asp 226 , Ser 321 ). Phylogenetic analysis showed that SpcSP was clustered together with PtcSP (clip domain serine proteinase from Portunus trituberculatus). Quantitative real-time PCR (qPCR) analysis showed that the mRNA of SpcSP was constitutively expressed at different levels in all tested tissues in untreated S. paramamosain, with hemocytes and skin expressing the most. The transcriptional level of SpcSP in hemocytes was significantly up-regulated upon challenge with V. parahaemolyticus and LPS, indicating its involvement in antibacterial immune response. Indirect immunofluorescence analysis showed that SpcSP was expressed in the cytoplasm of all three hemocyte cell types (hyaline, semigranular and granular cells). Further, recombinant SpcSP protein exhibited strong binding ability and has antimicrobial activity against both Gram-positive and Gram-negative bacteria as well as fungi. Moreover, knockdown of SpcSP resulted in increased hemolymph clotting time and decreased the mRNA expression of SpproPO mRNA in hemocytes. These findings therefore suggest that SpcSP plays an important role in the antimicrobial defense mechanism of S. paramamosain by regulating the expression of SpproPO and hemolymph clotting in S. paramamosain. Copyright © 2018. Published by Elsevier Ltd.

First results from the NEWS-G direct dark matter search experiment at the LSM

NASA Astrophysics Data System (ADS)

Arnaud, Q.; Asner, D.; Bard, J.-P.; Brossard, A.; Cai, B.; Chapellier, M.; Clark, M.; Corcoran, E. C.; Dandl, T.; Dastgheibi-Fard, A.; Dering, K.; Di Stefano, P.; Durnford, D.; Gerbier, G.; Giomataris, I.; Gorel, P.; Gros, M.; Guillaudin, O.; Hoppe, E. W.; Kamaha, A.; Katsioulas, I.; Kelly, D. G.; Martin, R. D.; McDonald, J.; Muraz, J.-F.; Mols, J.-P.; Navick, X.-F.; Papaevangelou, T.; Piquemal, F.; Roth, S.; Santos, D.; Savvidis, I.; Ulrich, A.; Vazquez de Sola Fernandez, F.; Zampaolo, M.

2018-01-01

New Experiments With Spheres-Gas (NEWS-G) is a direct dark matter detection experiment using Spherical Proportional Counters (SPCs) with light noble gases to search for low-mass Weakly Interacting Massive Particles (WIMPs). We report the results from the first physics run taken at the Laboratoire Souterrain de Modane (LSM) with SEDINE, a 60 cm diameter prototype SPC operated with a mixture of Ne + CH4 (0.7%) at 3.1 bars for a total exposure of 9.6 kg · days. New constraints are set on the spin-independent WIMP-nucleon scattering cross-section in the sub-GeV/c2 mass region. We exclude cross-sections above 4.4 ×10-37cm2 at 90% confidence level (C.L.) for a 0.5 GeV/c2 WIMP. The competitive results obtained with SEDINE are promising for the next phase of the NEWS-G experiment: a 140 cm diameter SPC to be installed at SNOLAB by summer 2018.

Biodegradable nanoparticles loaded with insulin-phospholipid complex for oral delivery: preparation, in vitro characterization and in vivo evaluation.

PubMed

Cui, Fude; Shi, Kai; Zhang, Liqiang; Tao, Anjin; Kawashima, Yoshiaki

2006-08-28

Biodegradable nanoparticles loaded with insulin-phospholipid complex were prepared by a novel reverse micelle-solvent evaporation method, in which soybean phosphatidylcholine (SPC) was employed to improve the liposolubility of insulin, and biodegradable polymers as carrier materials to control drug release. Solubilization study, IR and X-ray diffraction analysis were employed to prove the complex formation. The effects of key parameters such as polymer/SPC weight ratio, organic phase and polymer type on the properties of the nanoparticles were investigated. Spherical particles of 200 nm mean diameter and a narrow size distribution were obtained under optimal conditions. The drug entrapment efficiency was up to 90%. The in vitro drug release was characterized by an initial burst and subsequent delayed release in both pH 6.8 and pH 1.2 dissolution mediums. The specific modality of drug release, i.e., free or SPC-combined, was investigated in the aid of ultracentrifugation and ultrafiltration methods. The influence of polymer type on the drug release was also discussed. The pharmacological effects of the nanoparticles made of PLGA 50/50 (Av.Mw 9500) were further evaluated to confirm their potential suitability for oral delivery. Intragastric administration of the 20 IU/kg nanoparticles reduced fasting plasma glucose levels to 57.4% within the first 8 h of administration and this continued for 12 h. PK/PD analysis indicated that 7.7% of oral bioavailability relative to subcutaneous injection was obtained.

Molecular simulation of thermodynamic and transport properties for the H{sub 2}O+NaCl system

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

Orozco, Gustavo A.; Jiang, Hao; Panagiotopoulos, Athanassios Z., E-mail: azp@princeton.edu

Molecular dynamics and Monte Carlo simulations have been carried out to obtain thermodynamic and transport properties of the binary mixture H{sub 2}O+NaCl at temperatures from T = 298 to 473 K. In particular, vapor pressures, liquid densities, viscosities, and vapor-liquid interfacial tensions have been obtained as functions of pressure and salt concentration. Several previously proposed fixed-point-charge models that include either Lennard-Jones (LJ) 12-6 or exponential-6 (Exp6) functional forms to describe non-Coulombic interactions were studied. In particular, for water we used the SPC and SPC/E (LJ) models in their rigid forms, a semiflexible version of the SPC/E (LJ) model, and themore » Errington-Panagiotopoulos Exp6 model; for NaCl, we used the Smith-Dang and Joung-Cheatham (LJ) parameterizations as well as the Tosi-Fumi (Exp6) model. While none of the model combinations are able to reproduce simultaneously all target properties, vapor pressures are well represented using the SPC plus Joung-Cheathem model combination, and all LJ models do well for the liquid density, with the semiflexible SPC/E plus Joung-Cheatham combination being the most accurate. For viscosities, the combination of rigid SPC/E plus Smith-Dang is the best alternative. For interfacial tensions, the combination of the semiflexible SPC/E plus Smith-Dang or Joung-Cheatham gives the best results. Inclusion of water flexibility improves the mixture densities and interfacial tensions, at the cost of larger deviations for the vapor pressures and viscosities. The Exp6 water plus Tosi-Fumi salt model combination was found to perform poorly for most of the properties of interest, in particular being unable to describe the experimental trend for the vapor pressure as a function of salt concentration.« less

Detective quantum efficiency of photon-counting x-ray detectors

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

Tanguay, Jesse, E-mail: jessetan@mail.ubc.ca; Yun, Seungman; Kim, Ho Kyung

Purpose: Single-photon-counting (SPC) x-ray imaging has the potential to improve image quality and enable novel energy-dependent imaging methods. Similar to conventional detectors, optimizing image SPC quality will require systems that produce the highest possible detective quantum efficiency (DQE). This paper builds on the cascaded-systems analysis (CSA) framework to develop a comprehensive description of the DQE of SPC detectors that implement adaptive binning. Methods: The DQE of SPC systems can be described using the CSA approach by propagating the probability density function (PDF) of the number of image-forming quanta through simple quantum processes. New relationships are developed to describe PDF transfermore » through serial and parallel cascades to accommodate scatter reabsorption. Results are applied to hypothetical silicon and selenium-based flat-panel SPC detectors including the effects of reabsorption of characteristic/scatter photons from photoelectric and Compton interactions, stochastic conversion of x-ray energy to secondary quanta, depth-dependent charge collection, and electronic noise. Results are compared with a Monte Carlo study. Results: Depth-dependent collection efficiency can result in substantial broadening of photopeaks that in turn may result in reduced DQE at lower x-ray energies (20–45 keV). Double-counting interaction events caused by reabsorption of characteristic/scatter photons may result in falsely inflated image signal-to-noise ratio and potential overestimation of the DQE. Conclusions: The CSA approach is extended to describe signal and noise propagation through photoelectric and Compton interactions in SPC detectors, including the effects of escape and reabsorption of emission/scatter photons. High-performance SPC systems can be achieved but only for certain combinations of secondary conversion gain, depth-dependent collection efficiency, electronic noise, and reabsorption characteristics.« less

Detective quantum efficiency of photon-counting x-ray detectors.

PubMed

Tanguay, Jesse; Yun, Seungman; Kim, Ho Kyung; Cunningham, Ian A

2015-01-01

Single-photon-counting (SPC) x-ray imaging has the potential to improve image quality and enable novel energy-dependent imaging methods. Similar to conventional detectors, optimizing image SPC quality will require systems that produce the highest possible detective quantum efficiency (DQE). This paper builds on the cascaded-systems analysis (CSA) framework to develop a comprehensive description of the DQE of SPC detectors that implement adaptive binning. The DQE of SPC systems can be described using the CSA approach by propagating the probability density function (PDF) of the number of image-forming quanta through simple quantum processes. New relationships are developed to describe PDF transfer through serial and parallel cascades to accommodate scatter reabsorption. Results are applied to hypothetical silicon and selenium-based flat-panel SPC detectors including the effects of reabsorption of characteristic/scatter photons from photoelectric and Compton interactions, stochastic conversion of x-ray energy to secondary quanta, depth-dependent charge collection, and electronic noise. Results are compared with a Monte Carlo study. Depth-dependent collection efficiency can result in substantial broadening of photopeaks that in turn may result in reduced DQE at lower x-ray energies (20-45 keV). Double-counting interaction events caused by reabsorption of characteristic/scatter photons may result in falsely inflated image signal-to-noise ratio and potential overestimation of the DQE. The CSA approach is extended to describe signal and noise propagation through photoelectric and Compton interactions in SPC detectors, including the effects of escape and reabsorption of emission/scatter photons. High-performance SPC systems can be achieved but only for certain combinations of secondary conversion gain, depth-dependent collection efficiency, electronic noise, and reabsorption characteristics.

Genetic element from human surfactant protein SP-C gene confers bronchiolar-alveolar cell specificity in transgenic mice.

PubMed

Glasser, S W; Korfhagen, T R; Wert, S E; Bruno, M D; McWilliams, K M; Vorbroker, D K; Whitsett, J A

1991-10-01

Transgenic mice bearing chimeric genes consisting of 5'-sequences derived from the human surfactant protein C (SP-C) gene and the bacterial chloramphenicol acetyltransferase (CAT) gene were generated. Analysis of CAT activity was utilized to demonstrate tissue-specific and developmental expression of chimeric genes containing 3.7 kb of sequences from the human SP-C gene. Lung-specific expression of the 3.7 SP-C-CAT transgene was observed in eight distinct transgenic mouse lines. Expression of the 3.7 SP-C-CAT transgene was first detected in fetal lung on day 11 of gestation and increased dramatically with advancing gestational age, reaching adult levels of activity before birth. In situ hybridization demonstrated that expression of 3.7 SP-C-CAT mRNA was confined to the distal respiratory epithelium. Antisense CAT hybridization was detected in bronchiolar and type II epithelial cells in the adult lung of the 3.7 SP-C-CAT transgenic mice. In situ hybridization of four distinct 3.7 SP-C-CAT transgenic mouse lines demonstrated bronchiolar-alveolar expression of the chimeric CAT gene, although the relative intensity of expression at each site varied within the lines studied. Glucocorticoids increased murine SP-C mRNA in fetal lung organ culture. Likewise, expression of 3.7 SP-C-CAT transgene increased during fetal lung organ or explant culture and was further enhanced by glucocorticoid in vitro. The 5'-regions of human SP-C conferred developmental, lung epithelial, and glucocorticoid-enhanced expression of bacterial CAT in transgenic mice. The increased expression of SP-C accompanying prenatal lung development and exposure to glucocorticoid is mediated, at least in part, at the transcriptional level, being influenced by cis-active elements contained within the 5'-flanking region of the human SP-C gene.

Initiating statistical process control to improve quality outcomes in colorectal surgery.

PubMed

Keller, Deborah S; Stulberg, Jonah J; Lawrence, Justin K; Samia, Hoda; Delaney, Conor P

2015-12-01

Unexpected variations in postoperative length of stay (LOS) negatively impact resources and patient outcomes. Statistical process control (SPC) measures performance, evaluates productivity, and modifies processes for optimal performance. The goal of this study was to initiate SPC to identify LOS outliers and evaluate its feasibility to improve outcomes in colorectal surgery. Review of a prospective database identified colorectal procedures performed by a single surgeon. Patients were grouped into elective and emergent categories and then stratified by laparoscopic and open approaches. All followed a standardized enhanced recovery protocol. SPC was applied to identify outliers and evaluate causes within each group. A total of 1294 cases were analyzed--83% elective (n = 1074) and 17% emergent (n = 220). Emergent cases were 70.5% open and 29.5% laparoscopic; elective cases were 36.8% open and 63.2% laparoscopic. All groups had a wide range in LOS. LOS outliers ranged from 8.6% (elective laparoscopic) to 10.8% (emergent laparoscopic). Evaluation of outliers demonstrated patient characteristics of higher ASA scores, longer operating times, ICU requirement, and temporary nursing at discharge. Outliers had higher postoperative complication rates in elective open (57.1 vs. 20.0%) and elective lap groups (77.6 vs. 26.1%). Outliers also had higher readmission rates for emergent open (11.4 vs. 5.4%), emergent lap (14.3 vs. 9.2%), and elective lap (32.8 vs. 6.9%). Elective open outliers did not follow trends of longer LOS or higher reoperation rates. SPC is feasible and promising for improving colorectal surgery outcomes. SPC identified patient and process characteristics associated with increased LOS. SPC may allow real-time outlier identification, during quality improvement efforts, and reevaluation of outcomes after introducing process change. SPC has clinical implications for improving patient outcomes and resource utilization.

Surfactant Protein–C Chromatin-Bound Green Fluorescence Protein Reporter Mice Reveal Heterogeneity of Surfactant Protein C–Expressing Lung Cells

PubMed Central

Lee, Joo-Hyeon; Kim, Jonghwan; Gludish, David; Roach, Rebecca R.; Saunders, Arven H.; Barrios, Juliana; Woo, Andrew Jonghan; Chen, Huaiyong; Conner, David A.; Fujiwara, Yuko; Stripp, Barry R.

2013-01-01

The regeneration of alveolar epithelial cells is a critical aspect of alveolar reorganization after lung injury. Although alveolar Type II (AT2) cells have been described as progenitor cells for alveolar epithelia, more remains to be understood about how their progenitor cell properties are regulated. A nuclear, chromatin-bound green fluorescence protein reporter (H2B-GFP) was driven from the murine surfactant protein–C (SPC) promoter to generate SPC H2B-GFP transgenic mice. The SPC H2B-GFP allele allowed the FACS-based enrichment and gene expression profiling of AT2 cells. Approximately 97% of AT2 cells were GFP-labeled on Postnatal Day 1, and the percentage of GFP-labeled AT2 cells decreased to approximately 63% at Postnatal Week 8. Isolated young adult SPC H2B-GFP+ cells displayed proliferation, differentiation, and self-renewal capacity in the presence of lung fibroblasts in a Matrigel-based three-dimensional culture system. Heterogeneity within the GFP+ population was revealed, because cells with distinct alveolar and bronchiolar gene expression arose in three-dimensional cultures. CD74, a surface marker highly enriched on GFP+ cells, was identified as a positive selection marker, providing 3-fold enrichment for AT2 cells. In vivo, GFP expression was induced within other epithelial cell types during maturation of the distal lung. The utility of the SPC H2B-GFP murine model for the identification of AT2 cells was greatest in early postnatal lungs and more limited with age, when some discordance between SPC and GFP expression was observed. In adult mice, this allele may allow for the enrichment and future characterization of other SPC-expressing alveolar and bronchiolar cells, including putative stem/progenitor cell populations. PMID:23204392

Does tablet formulation alone improve adherence and persistence: a comparison of ezetimibe fixed dose combination versus ezetimibe separate pill combination?

PubMed

Bartlett, Louise E; Pratt, Nicole; Roughead, Elizabeth E

2017-01-01

The aim of this study was to compare adherence and persistence in patients who add ezetimibe to statin therapy as a separate pill combination (SPC) or fixed dose combination (FDC). This is a retrospective cohort study of prescription data conducted in an Australian health dataset. Two cohorts were identified: those dispensed statins and subsequently ezetimibe as either SPC or FDC. We compared adherence to combination therapy using the medication possession ratio (MPR), multivariate linear and logistic regression. Persistence to initial combination medicines and any lipid-lowering therapies were analysed using Kaplan Meyer survival and Cox proportional hazards models. A total of 3651 people initiated ezetimibe SPC and 5740 ezetimibe FDC. There was no significant difference in adherence with mean MPRs: ezetimibe SPC = 0.99 (95% confidence interval 0.98-1.01) and FDC = 0.97 (95% CI 0.95-0.99). One year persistence rates to initial combination medicines were ezetimibe SPC 49.1% vs. FDC 62.4%; hazard ratio (HR) = 1.81 (95% CI 1.76-1.90). However, persistence to any lipid-lowering therapy was higher in those initiating ezetimibe SPC = 84.9% vs. FDC = 76%; HR = 0.62 (95% CI 0.55-0.72). One year persistence rates to any two lipid-lowering medicines were similar: ezetimibe SPC 65.2% and FDC 65%. In this study FDCs have little impact on either adherence or persistence to combination lipid-lowering therapy in people who have been taking statins. The benefit of higher persistence to FDCs in first episode of treatment with initial medicines is debatable as persistence to dual therapy was similar in both cohorts. © 2016 The British Pharmacological Society.

Does tablet formulation alone improve adherence and persistence: a comparison of ezetimibe fixed dose combination versus ezetimibe separate pill combination?

PubMed Central

Pratt, Nicole; Roughead, Elizabeth E.

2016-01-01

Aims The aim of this study was to compare adherence and persistence in patients who add ezetimibe to statin therapy as a separate pill combination (SPC) or fixed dose combination (FDC). Method This is a retrospective cohort study of prescription data conducted in an Australian health dataset. Two cohorts were identified: those dispensed statins and subsequently ezetimibe as either SPC or FDC. We compared adherence to combination therapy using the medication possession ratio (MPR), multivariate linear and logistic regression. Persistence to initial combination medicines and any lipid‐lowering therapies were analysed using Kaplan Meyer survival and Cox proportional hazards models. Results A total of 3651 people initiated ezetimibe SPC and 5740 ezetimibe FDC. There was no significant difference in adherence with mean MPRs: ezetimibe SPC = 0.99 (95% confidence interval 0.98–1.01) and FDC = 0.97 (95% CI 0.95–0.99). One year persistence rates to initial combination medicines were ezetimibe SPC 49.1% vs. FDC 62.4%; hazard ratio (HR) = 1.81 (95% CI 1.76–1.90). However, persistence to any lipid‐lowering therapy was higher in those initiating ezetimibe SPC = 84.9% vs. FDC = 76%; HR = 0.62 (95% CI 0.55–0.72). One year persistence rates to any two lipid‐lowering medicines were similar: ezetimibe SPC 65.2% and FDC 65%. Conclusion In this study FDCs have little impact on either adherence or persistence to combination lipid‐lowering therapy in people who have been taking statins. The benefit of higher persistence to FDCs in first episode of treatment with initial medicines is debatable as persistence to dual therapy was similar in both cohorts. PMID:27517705

Calibration of a modified temperature-light intensity logger for quantifying water electrical conductivity

NASA Astrophysics Data System (ADS)

Gillman, M. A.; Lamoureux, S. F.; Lafrenière, M. J.

2017-09-01

The Stream Temperature, Intermittency, and Conductivity (STIC) electrical conductivity (EC) logger as presented by Chapin et al. (2014) serves as an inexpensive (˜50 USD) means to assess relative EC in freshwater environments. This communication demonstrates the calibration of the STIC logger for quantifying EC, and provides examples from a month long field deployment in the High Arctic. Calibration models followed multiple nonlinear regression and produced calibration curves with high coefficient of determination values (R2 = 0.995 - 0.998; n = 5). Percent error of mean predicted specific conductance at 25°C (SpC) to known SpC ranged in magnitude from -0.6% to 13% (mean = -1.4%), and mean absolute percent error (MAPE) ranged from 2.1% to 13% (mean = 5.3%). Across all tested loggers we found good accuracy and precision, with both error metrics increasing with increasing SpC values. During 10, month-long field deployments, there were no logger failures and full data recovery was achieved. Point SpC measurements at the location of STIC loggers recorded via a more expensive commercial electrical conductivity logger followed similar trends to STIC SpC records, with 1:1.05 and 1:1.08 relationships between the STIC and commercial logger SpC values. These results demonstrate that STIC loggers calibrated to quantify EC are an economical means to increase the spatiotemporal resolution of water quality investigations.

Sputum, sex and scanty smears: new case definition may reduce sex disparities in smear-positive tuberculosis.

PubMed

Ramsay, A; Bonnet, M; Gagnidze, L; Githui, W; Varaine, F; Guérin, P J

2009-05-01

Urban clinic, Nairobi. To evaluate the impact of specimen quality and different smear-positive tuberculosis (TB) case (SPC) definitions on SPC detection by sex. Prospective study among TB suspects. A total of 695 patients were recruited: 644 produced > or =1 specimen for microscopy. The male/female sex ratio was 0.8. There were no significant differences in numbers of men and women submitting three specimens (274/314 vs. 339/380, P = 0.43). Significantly more men than women produced a set of three 'good' quality specimens (175/274 vs. 182/339, P = 0.01). Lowering thresholds for definitions to include scanty smears resulted in increases in SPC detection in both sexes; the increase was significantly higher for women. The revised World Health Organization (WHO) case definition was associated with the highest detection rates in women. When analysis was restricted only to patients submitting 'good' quality specimen sets, the difference in detection between sexes was on the threshold for significance (P = 0.05). Higher SPC notification rates in men are commonly reported by TB control programmes. The revised WHO SPC definition may reduce sex disparities in notification. This should be considered when evaluating other interventions aimed at reducing these. Further study is required on the effects of the human immuno-deficiency virus and instructed specimen collection on sex-specific impact of new SPC definition.

Short communication: Repeatability of differential goat bulk milk culture and associations with somatic cell count, total bacterial count, and standard plate count.

PubMed

Koop, G; Dik, N; Nielen, M; Lipman, L J A

2010-06-01

The aims of this study were to assess how different bacterial groups in bulk milk are related to bulk milk somatic cell count (SCC), bulk milk total bacterial count (TBC), and bulk milk standard plate count (SPC) and to measure the repeatability of bulk milk culturing. On 53 Dutch dairy goat farms, 3 bulk milk samples were collected at intervals of 2 wk. The samples were cultured for SPC, coliform count, and staphylococcal count and for the presence of Staphylococcus aureus. Furthermore, SCC (Fossomatic 5000, Foss, Hillerød, Denmark) and TBC (BactoScan FC 150, Foss) were measured. Staphylococcal count was correlated to SCC (r=0.40), TBC (r=0.51), and SPC (r=0.53). Coliform count was correlated to TBC (r=0.33), but not to any of the other variables. Staphylococcus aureus did not correlate to SCC. The contribution of the staphylococcal count to the SPC was 31%, whereas the coliform count comprised only 1% of the SPC. The agreement of the repeated measurements was low. This study indicates that staphylococci in goat bulk milk are related to SCC and make a significant contribution to SPC. Because of the high variation in bacterial counts, repeated sampling is necessary to draw valid conclusions from bulk milk culturing. 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Palliative care for cirrhosis: a UK survey of health professionals’ perceptions, current practice and future needs

PubMed Central

Low, Joseph; Vickerstaff, Victoria; Davis, Sarah; Bichard, Julia; Greenslade, Lynda; Hopkins, Katherine; Marshall, Aileen; Thorburn, Douglas; Jones, Louise

2016-01-01

Objective To determine the knowledge and practice patterns of a UK cohort of relevant healthcare professionals (HCPs) about delivering palliative care in cirrhosis, and to inform priorities for future research. Design An on-line questionnaire survey with closed and open responses. Setting HCPs identified from the mailing list of special interest groups in hepatology and gastroenterology (liver), general practice and specialist palliative care (SPC) across the UK. Results Of the 6181 potential contacts identified, 517 HCPs responded. Most believed a role exists for SPC in caring for people with cirrhosis, but many SPC HCPs felt ill prepared to provide good care to those facing death. Further training was needed in managing liver-related symptoms, symptom control and end of life issues. All HCP groups wished to increase community provision of palliative care support, but many general practitioners felt unable to manage advanced cirrhosis in the community. There were differences in the optimal trigger for SPC referral with liver HCPs less likely to refer at symptom deterioration. Prognostication, symptom management and service configuration were key areas identified for future research. Conclusions All who responded acknowledged the role of SPC in caring for those dying with cirrhosis and need for further training to improve confidence and enable joint working between SPC, general practice and liver teams. Low response rates make it difficult to generalise these findings, which require further validation. PMID:28839829

Statistical Process Control for KSC Processing

NASA Technical Reports Server (NTRS)

Ford, Roger G.; Delgado, Hector; Tilley, Randy

1996-01-01

The 1996 Summer Faculty Fellowship Program and Kennedy Space Center (KSC) served as the basis for a research effort into statistical process control for KSC processing. The effort entailed several tasks and goals. The first was to develop a customized statistical process control (SPC) course for the Safety and Mission Assurance Trends Analysis Group. The actual teaching of this course took place over several weeks. In addition, an Internet version of the same course complete with animation and video excerpts from the course when it was taught at KSC was developed. The application of SPC to shuttle processing took up the rest of the summer research project. This effort entailed the evaluation of SPC use at KSC, both present and potential, due to the change in roles for NASA and the Single Flight Operations Contractor (SFOC). Individual consulting on SPC use was accomplished as well as an evaluation of SPC software for KSC use in the future. A final accomplishment of the orientation of the author to NASA changes, terminology, data format, and new NASA task definitions will allow future consultation when the needs arise.

Spiramycin/cotrimoxazole versus pyrimethamine/sulfonamide and spiramycin alone for the treatment of toxoplasmosis in pregnancy.

PubMed

Valentini, P; Buonsenso, D; Barone, G; Serranti, D; Calzedda, R; Ceccarelli, M; Speziale, D; Ricci, R; Masini, L

2015-02-01

To compare the effectiviness of spiramycin/cotrimoxazole (Sp/C) versus pyrimethamine/sulfonamide (Pyr/Sul) and spiramycin alone (Spy) on mother-to-child transmission of toxoplasmosis infection in pregnancy. Retrospective study of pregnant women evaluated for suspected toxoplasmosis between 1992 and 2011. A total of 120 mothers and their 123 newborns were included. Prenatal treatment consisted of spiramycin in 43 mothers (35%), spiramycin/cotrimoxazole in 70 (56.9%) and pyrimethamine/sulfonamide in 10 (8.1%). A trend toward reduction in toxoplasmosis transmission was found when Sp/C was compared with Pyr/Sul and particularly with Spy alone (P=0.014). In particular, Spy increased the risk of congenital infection when compared with Sp/C (odds ratio (OR) 4.368; 95% CI: 1.253 to 15.219), but there was no significant reduction when Sp/C was compared with Pyr/Sul (OR 1.83; 95% CI: 0.184 to 18.274). The treatment based on Sp/C has significant efficacy in reducing maternal-fetal transmission of Toxoplasma gondii when compared with Pyr/Sul and particularly to Spy. Randomized controlled trials would be required.

Shaped pupil coronagraphy for WFIRST: high-contrast broadband testbed demonstration

NASA Astrophysics Data System (ADS)

Cady, Eric; Balasubramanian, Kunjithapatham; Gersh-Range, Jessica; Kasdin, Jeremy; Kern, Brian; Lam, Raymond; Mejia Prada, Camilo; Moody, Dwight; Patterson, Keith; Poberezhskiy, Ilya; Riggs, A. J. Eldorado; Seo, Byoung-Joon; Shi, Fang; Tang, Hong; Trauger, John; Zhou, Hanying; Zimmerman, Neil

2017-09-01

The Shaped Pupil Coronagraph (SPC) is one of the two operating modes of the WFIRST coronagraph instrument. The SPC provides starlight suppression in a pair of wedge-shaped regions over an 18% bandpass, and is well suited for spectroscopy of known exoplanets. To demonstrate this starlight suppression in the presence of expected onorbit input wavefront disturbances, we have recently built a dynamic testbed at JPL analogous to the WFIRST flight instrument architecture, with both Hybrid Lyot Coronagraph (HLC) and SPC architectures and a Low Order Wavefront Sensing and Control (LOWFS/C) subsystem to apply, sense, and correct dynamic wavefront disturbances. We present our best up-to-date results of the SPC mode demonstration from the testbed, in both static and dynamic conditions, along with model comparisons. HLC results will be reported separately.

An in-situ analytical scanning and transmission electron microscopy investigation of structure-property relationships in electronic materials

NASA Astrophysics Data System (ADS)

Wagner, Andrew James

As electronic and mechanical devices are scaled downward in size and upward in complexity, macroscopic principles no longer apply. Synthesis of three-dimensionally confined structures exhibit quantum confinement effects allowing, for example, silicon nanoparticles to luminesce. The reduction in size of classically brittle materials reveals a ductile-to-brittle transition. Such a transition, attributed to a reduction in defects, increases elasticity. In the case of silicon, elastic deformation can improve electronic carrier mobility by over 50%, a vital attribute of modern integrated circuits. The scalability of such principles and the changing atomistic processes which contribute to them presents a vitally important field of research. Beginning with the direct observation of dislocations and lattice planes in the 1950s, the transmission electron microscope has been a powerful tool in materials science. More recently, as nanoscale technologies have proliferated modern life, their unique ability to spatially resolve nano- and atomic-scale structures has become a critical component of materials research and characterization. Signals produced by an incident beam of high-energy electrons enables researchers to both image and chemically analyze materials at the atomic scale. Coherently and elastically-scattered electrons can be collected to produce atomic-scale images of a crystalline sample. New specimen stages have enabled routine investigation of samples heated up to 1000 °C and cooled to liquid nitrogen temperatures. MEMS-based transducers allow for sub-nm scale mechanical testing and ultrathin membranes allow study of liquids and gases. Investigation of a myriad of previously "unseeable" processes can now be observed within the TEM, and sometimes something new is found within the old. High-temperature annealing of pure a Si:H films leads to crystallization of the film. Such films provide higher carrier mobility compared to amorphous films, offering improved photovoltaic performance. The annealing process, however, requires exceptionally high temperature (> 600 °C) and time (tens of hours), limiting throughput and costing energy. In an effort to fabricate polycrystalline solar cells at lower cost, large ( 30 nm) silicon nanocrystals were incorporated into hydrogenated amorphous silicon (a Si:H) thin films. When annealed, the embedded nanocrystals were expected to act as heterogeneous nucleation sites and crystallize the surrounding amorphous matrix. When observed in the TEM, an additional and unexpected event was observed. At the boundary between the nanocrystal and amorphous matrix, nanocavities were observed to form. Continued annealing resulted in movement of the cavities away from the nanocrystal while leaving behind a crystalline tail. The origins and fundamental mechanisms of this phenomenon were examined by in-situ heating TEM and ex-situ crystallographic TEM techniques. We demonstrate a mechanism of solid-phase crystallization (SPC) enabled by nanoscale cavities formed at the interface between an hydrogenated amorphous silicon film and embedded 30 nm to 40 nm Si nanocrystals. The nanocavities, 10 nm to 25 nm across, have the unique property of an internal surface that is part amorphous and part crystalline, enabling capillarity-driven diffusion from the amorphous to the crystalline domain. The nanocavities propagate rapidly through the amorphous phase, up to five times faster than the SPC growth rate, while "pulling behind" a crystalline tail. It is shown that twin boundaries exposed on the crystalline surface accelerate crystal growth and influence the direction of nanocavity propagation. The mechanical properties and mechanisms of plasticity in these same silicon nanocubes have also been investigated. The strain-dependent mechanical properties and the underlying mechanisms governing the elastic-plastic response are explored in detail. Elastic strains approaching 7% and flow stresses of 11 GPa were observed, significantly higher than that observed in other nanoscale volumes of Si. In-situ imaging revealed the formation of 5 nm dislocation embryos at 7% strain, giving way at 20% strain to continuous nucleation of leading partial dislocations with {111}-habit at the embryo surface.

Laboratory and On-Sky Validation of the Shaped Pupil Coronagraph's Sensitivity to Low-Order Aberrations with Active Wavefront Control

NASA Technical Reports Server (NTRS)

Currie, Thayne; Lozi, Julien; Guyon, Olivier; Brandt, Timothy; Chilcote, Jeffrey; Skaf, Nour; Pathak, Prashant; Kasdin, N. Jeremy; Kuhn, Jonas; Groff, Tyler D.;

National Weather Service: Watch, Warning, Advisory Display

MedlinePlus

... Education & Outreach About the SPC SPC FAQ About Tornadoes About Derechos Video Lecture Series WCM Page Enh. ... Convective/Tropical Weather Flooding Winter Weather Non-Precipitation Tornado Watch Tornado Warning* Severe Thunderstorm Watch Severe Thunderstorm ...

Storm Prediction Center Fire Weather Forecasts

Science.gov Websites

Archive NOAA Weather Radio Research Non-op. Products Forecast Tools Svr. Tstm. Events SPC Publications SPC Composite Maps Fire Weather Graphical Composite Maps Forecast and observational maps for various fire

Treatment of chemical warfare agent casualties: retention of knowledge and self-perceived competency among military physicians and paramedics.

PubMed

Shiyovich, Arthur; Statlender, Liran; Abu-Tailakh, Muhammad; Plakht, Ygal; Shrot, Shai; Kassirer, Michael

2015-06-01

Specialized training of medical teams for chemical warfare agent (CWA) events is important to save lives. We aimed to evaluate the retention of knowledge (ROK) and self-perceived competency (SPC) of military medical personnel in delivering treatment during CWA events. A questionnaire and a multiple-choice examination were sent to military physicians and paramedics, evaluating their CWA, ROK, and SPC (study group [SG]). Their assessment was compared to medical personnel immediately post training (reference group [RG]). SG was subdivided into two groups: G1 ≤ 1 year and G2 > 1 year, past training. Overall, 135 participants responded (35-RG, 65% physicians). Self-reported ROK and SPC were significantly higher in RG compared to SG and in G1 compared to G2. Test scores were higher in RG compared to SG, but similar in G1 and G2 groups. SPC was lower compared to ROK in the entire cohort and subgroups. A moderate correlation was found between the self-and test-assessed scores (Pearson correlation coefficient 0.45, p < 0.001). Physicians received significantly (p = 0.01) higher test scores in RG compared with paramedics. ROK and SPC among military medical personnel for treatment of CWA casualties deteriorate significantly as early as 1 year post training, SPC > ROK. Thus, we recommend CWA refresher training at least every year. Reprint & Copyright © 2015 Association of Military Surgeons of the U.S.

A novel trigger for cholesterol-dependent smooth muscle contraction mediated by the sphingosylphosphorylcholine-Rho-kinase pathway in the rat basilar artery: a mechanistic role for lipid rafts.

PubMed

Shirao, Satoshi; Yoneda, Hiroshi; Shinoyama, Mizuya; Sugimoto, Kazutaka; Koizumi, Hiroyasu; Ishihara, Hideyuki; Oka, Fumiaki; Sadahiro, Hirokazu; Nomura, Sadahiro; Fujii, Masami; Tamechika, Masakatsu; Kagawa, Yoshiteru; Owada, Yuji; Suzuki, Michiyasu

2015-05-01

Hyperlipidemia is a risk factor for abnormal cerebrovascular events. Rafts are cholesterol-enriched membrane microdomains that influence signal transduction. We previously showed that Rho-kinase-mediated Ca(2+) sensitization of vascular smooth muscle (VSM) induced by sphingosylphosphorylcholine (SPC) has a pivotal role in cerebral vasospasm. The goals of the study were to show SPC-Rho-kinase-mediated VSM contraction in vivo and to link this effect to cholesterol and rafts. The SPC-induced VSM contraction measured using a cranial window model was reversed by Y-27632, a Rho-kinase inhibitor, in rats fed a control diet. The extent of SPC-induced contraction correlated with serum total cholesterol. Total cholesterol levels in the internal carotid artery (ICA) were significantly higher in rats fed a cholesterol diet compared with a control diet or a β-cyclodextrin diet, which depletes VSM cholesterol. Western blotting and real-time PCR revealed increases in flotillin-1, a raft marker, and flotillin-1 mRNA in the ICA in rats fed a cholesterol diet, but not in rats fed the β-cyclodextrin diet. Depletion of cholesterol decreased rafts in VSM cells, and prevention of an increase in cholesterol by β-cyclodextrin inhibited SPC-induced contraction in a cranial window model. These results indicate that cholesterol potentiates SPC-Rho-kinase-mediated contractions of importance in cerebral vasospasm and are compatible with a role for rafts in this process.

The impact of specialized palliative care on cancer patients' health-related quality of life: a systematic review and meta-analysis.

PubMed

Kassianos, Angelos P; Ioannou, Myria; Koutsantoni, Marianna; Charalambous, Haris

2018-01-01

Specialized palliative care (SPC) is currently underutilized or provided late in cancer care. The aim of this systematic review and meta-analysis is to critically evaluate the impact of SPC on patients' health-related quality of life (HRQoL). Five databases were searched through June 2016. Randomized controlled trials (RCTs) and prospective studies using a pre- and post- assessment of HRQoL were included. The PRISMA reporting statement was followed. Criteria from available checklists were used to evaluate the studies' quality. A meta-analysis followed using random-effect models separately for RCTs and non-RCTs. Eleven studies including five RCTs and 2939 cancer patients published between 2001 and 2014 were identified. There was improved HRQoL in patients with cancer following SPC especially in symptoms like pain, nausea, and fatigue as well as improvement of physical and psychological functioning. Less or no improvements were observed in social and spiritual domains. In general, studies of inpatients showed a larger benefit from SPC than studies of outpatients whereas patients' age and treatment duration did not moderate the impact of SPC. Methodological shortcomings of included studies include high attrition rates, low precision, and power and poor reporting of control procedures. The methodological problems and publication bias call for higher-quality studies to be designed, funded, and published. However, there is a clear message that SPC is multi-disciplinary and aims at palliation of symptoms and burden in line with current recommendations.

Economic evaluation of single-pill combination of indapamide and amlodipine in the treatment of arterial hypertension in the Polish setting.

PubMed

Kawalec, Paweł; Holko, Przemysław; Stawowczyk, Ewa; Borowiec, Łukasz; Filipiak, Krzysztof J

2015-01-01

Arterial hypertension is a common disorder that affects around 9 million adults in Poland. Single-pill combinations (SPCs) for the treatment of arterial hypertension have significant advantages over the free combinations, resulting in lower risk of cardiovascular events and lower consumption of medical resources. The current ESC/ESH 2013 guidelines for the first time recommend treatment with a combination of thiazide-like diuretic with calcium channel blocker. Currently, no such combination is reimbursed from public funds in Poland. To assess the economic value of treatment with SPC of indapamide and amlodipine (Tertens-AM®) for hypertensive patients compared with free combination therapy (FC), in the Polish setting. As there are currently no published data directly estimating the additional effect of using indapamide + amlo-dipine SPC vs. FC, two extreme approaches are presented: with difference in effectiveness due to improved adherence to the treatment estimated from published studies on other molecules used in hypertension such as SPCs and FCs - the base-case approach (1); and assuming no difference of effectiveness or adherence between SPC and FC of indapamide and amlodipine - the conservative approach (2). Modelling was carried out based on the Markov process in lifetime horizon. In the base-case approach, with the difference in effectiveness between SPC and FC, it was assumed that the differences in compliance translate into the differences in systolic blood pressure. Patients' characteristics were correlated with the risk of events associated with cardiovascular disease, based on the prediction algorithms from the Framingham Heart Study. Costs were considered from a National Health Fund (NHF) perspective and NHF and patient's perspective, and therefore direct medical costs were only included. The treatment with SPC of indapamide and amlodipine in place of FC resulted in 7.6 additional days of life in full health and longer overall patient survival by 2.9 days. The replacement of FC with SPC would result in national savings from both NHF perspective and NHF and patient's perspective, irrespective of the assumption of the difference in adherence between SPC and FC. The savings would amount to 1.602-3.954 million PLN and 16.498-19.186 million PLN from NHF perspective and NHF and patient's perspective, respectively. The treatment with SPC of indapamide and amlodipine for hypertensive patients was found to be dominant over FC or at least less expensive than treatment with FC when the difference in effectiveness was neglected. The replacement of FC with SPC would result in savings from both NHF perspective and NHF and patient's perspective.

Algorithms for GPU-based molecular dynamics simulations of complex fluids: Applications to water, mixtures, and liquid crystals.

PubMed

Kazachenko, Sergey; Giovinazzo, Mark; Hall, Kyle Wm; Cann, Natalie M

2015-09-15

A custom code for molecular dynamics simulations has been designed to run on CUDA-enabled NVIDIA graphics processing units (GPUs). The double-precision code simulates multicomponent fluids, with intramolecular and intermolecular forces, coarse-grained and atomistic models, holonomic constraints, Nosé-Hoover thermostats, and the generation of distribution functions. Algorithms to compute Lennard-Jones and Gay-Berne interactions, and the electrostatic force using Ewald summations, are discussed. A neighbor list is introduced to improve scaling with respect to system size. Three test systems are examined: SPC/E water; an n-hexane/2-propanol mixture; and a liquid crystal mesogen, 2-(4-butyloxyphenyl)-5-octyloxypyrimidine. Code performance is analyzed for each system. With one GPU, a 33-119 fold increase in performance is achieved compared with the serial code while the use of two GPUs leads to a 69-287 fold improvement and three GPUs yield a 101-377 fold speedup. © 2015 Wiley Periodicals, Inc.

Food-induced changes of lipids in rat neuronal tissue visualized by ToF-SIMS imaging.

PubMed

Dowlatshahi Pour, Masoumeh; Jennische, Eva; Lange, Stefan; Ewing, Andrew G; Malmberg, Per

2016-09-06

Time of flight secondary ion mass spectrometry (ToF-SIMS) was used to image the lipid localization in brain tissue sections from rats fed specially processed cereals (SPC). An IonTof 5 instrument equipped with a Bi cluster ion gun was used to analyze the tissue sections. Data from 15 brain samples from control and cereal-fed rats were recorded and exported to principal components analysis (PCA). The data clearly show changes of certain lipids in the brain following cereal feeding. PCA score plots show a good separation in lipid distribution between the control and the SPC-fed group. The loadings plot reveal that the groups separated mainly due to changes in cholesterol, vitamin E and c18:2, c16:0 fatty acid distribution as well as some short chain monocarboxylic fatty acid compositions. These insights relate to the working mechanism of SPC as a dietary supplement. SPC is thought to activate antisecretory factor (AF), an endogenous protein with regulatory function for inflammation and fluid secretion. These data provide insights into lipid content in brain following SPC feeding and suggest a relation to activating AF.

Immobilization of radioactive and hazardous wastes in a developed sulfur polymer cement (SPC) matrix

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

Wagdy, M.; Azim, Abdel; El-Gammal, Belal

Available in abstract form only. Full text of publication follows: A process has been developed for the immobilization Cs, Sr, Ce, Pb, and Cr in forms that is non-dispersible and could be safely immobilized. The simulated radioactive wastes of Cs, Sr, and Ce, and the hazardous wastes of Cr, and Pb were immobilized in the stable form of sulfur polymer cement (SPC). In this process, the contaminants (in a single form) were added to the sulfur mixture of sulfur and aromatic /or aliphatic hydrocarbons that used as polymerizing agents for sulfur (95% S, and 5% organic polymer by weight). Durabilitymore » of the fabricated SPC matrices was assessed in terms of their water of immersion, porosity, and compressive strength. The water immersion, and open porosity were found to be less than 2.5% for all the prepared matrices, whereas the compressive strength was in the range between 62.4 and 142.3 Kg.cm{sup -2}, depending on the composition of the prepared matrix. The prepared SPC matrices that characterized by X-ray diffraction (XRD) showed that the different added contaminants were stabilized during the solidification process during their reaction with sulfur and the organic polymer to form the corresponding metal sulfides. Toxicity Characteristic Leaching Procedure (TCLP), and the IAEA standard method have assessed the leachability of the prepared waste matrices. The TCLP results showed that most the concentration of the contaminants released were under their detection limit. The leach index for the investigated metals from the prepared SPC matrices was in the range of 9-11. The order of release of the investigated metals was Sr>Cs>Pb>Cr>Ce for the aliphatic polymer, and Sr>Cr>Pb>Cs>Ce for the aromatic one. The results obtained revealed a high performance for the prepared SPC matrices, as they are of low cost effect, highly available materials, and possessed good mechanical and leaching properties. Key Words: SPC/ Matrices/ Immobilization/ Wastes/ Leachability. (authors)« less

Bacterial aerosol emission rates from municipal wastewater aeration tanks.

PubMed Central

Sawyer, B; Elenbogen, G; Rao, K C; O'Brien, P; Zenz, D R; Lue-Hing, C

1993-01-01

In this report we describe the results of a study conducted to determine the rates of bacterial aerosol emission from the surfaces of the aeration tanks of the Metropolitan Water Reclamation District of Greater Chicago John E. Egan Water Reclamation Plant. This study was accomplished by conducting test runs in which Andersen six-stage viable samplers were used to collect bacterial aerosol samples inside a walled tower positioned above an aeration tank liquid surface at the John E. Egan Water Reclamation Plant. The samples were analyzed for standard plate counts (SPC), total coliforms (TC), fecal coliforms, and fecal streptococci. Two methods of calculation were used to estimate the bacterial emission rate. The first method was a conventional stack emission rate calculation method in which the measured air concentration of bacteria was multiplied by the air flow rate emanating from the aeration tanks. The second method was a more empirical method in which an attempt was made to measure all of the bacteria emanating from an isolated area (0.37 m2) of the aeration tank surface over time. The data from six test runs were used to determine bacterial emission rates by both calculation methods. As determined by the conventional calculation method, the average SPC emission rate was 1.61 SPC/m2/s (range, 0.66 to 2.65 SPC/m2/s). As determined by the empirical calculation method, the average SPC emission rate was 2.18 SPC/m2/s (range, 1.25 to 2.66 SPC/m2/s). For TC, the average emission rate was 0.20 TC/m2/s (range, 0.02 to 0.40 TC/m2/s) when the conventional calculation method was used and 0.27 TC/m2/s (range, 0.04 to 0.53 TC/m2/s) when the empirical calculation method was used.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8250547

Is admittance to specialised palliative care among cancer patients related to sex, age and cancer diagnosis? A nation-wide study from the Danish Palliative Care Database (DPD).

PubMed

Adsersen, Mathilde; Thygesen, Lau Caspar; Jensen, Anders Bonde; Neergaard, Mette Asbjoern; Sjøgren, Per; Groenvold, Mogens

2017-03-23

Specialised palliative care (SPC) takes place in specialised services for patients with complex symptoms and problems. Little is known about what determines the admission of patients to SPC and whether there are differences in relation to institution type. The aims of the study were to investigate whether cancer patients' admittance to SPC in Denmark varied in relation to sex, age and diagnosis, and whether the patterns differed by type of institution (hospital-based palliative care team/unit, hospice, or both). This was a register-based study of adult patients living in Denmark who died from cancer in 2010-2012. Data sources were the Danish Palliative Care Database, Danish Register of Causes of Death and Danish Cancer Registry. The associations between the explanatory variables (sex, age, diagnosis) and admittance to SPC were investigated using logistic regression. In the study population (N = 44,548) the overall admittance proportion to SPC was 37%. Higher odds of overall admittance to SPC were found for women (OR = 1.23; 1.17-1.28), younger patients (<40 compared with 80+ years old) (OR = 6.44; 5.19-7.99) and patients with sarcoma, pancreatic and stomach cancers, whereas the lowest were for patients with haematological malignancies. The higher admission found for women was most pronounced for hospices compared to hospital-based palliative care teams/units, whereas higher admission of younger patients was more pronounced for hospital-based palliative care teams/units. Patients with brain cancer were more often admitted to hospices, whereas patients with prostate cancer were more often admitted to hospital-based palliative care teams/units. It is unlikely that the variations in relation to sex, age and cancer diagnoses can be fully explained by differences in need. Future research should investigate whether the groups having the lowest admittance to SPC receive sufficient palliative care elsewhere.

The design and implementation of a broadband digital low-level RF control system for the cyclotron accelerators at iThemba LABS

NASA Astrophysics Data System (ADS)

Duckitt, W. D.; Conradie, J. L.; van Niekerk, M. J.; Abraham, J. K.; Niesler, T. R.

2018-07-01

iThemba LABS has successfully designed a new broadband digital low-level RF control system for cyclotrons, that operates over the wide frequency range of 2-100 MHz and can achieve peak-peak amplitude and phase stabilities of 0.01% and 0.01°, respectively. The presented system performs direct digital synthesis (DDS) to directly convert the digital RF signals to analog RF and local-oscillator (LO) signals with 16-bit amplitude accuracy, programmable in steps of 1 μHz and 0.0001°. Down-conversion of the RF pick-up signals to an optimal intermediate frequency (IF) of 1 MHz and sampling of the IF channels by 16-bit, single sample-latency 10 MHz ADCs was implemented to allow digital high-speed low-latency in-phase/quadrature (I/Q) demodulation of the IF channels within the FPGA. This in turn allows efficient real-time digital closed-loop control of the amplitude and phase of the RF drive-signal to be achieved. The systems have been successfully integrated at iThemba LABS into the K = 8 and K = 10 injector cyclotrons (SPC1, and SPC2), the K = 200 separated sector cyclotron (SSC), the SSC flat-topping system, the pulse-selector system and the AX , J, and K-line RF bunchers. The systems have led to a substantial improvement in the beam quality of the SSC at iThemba LABS with a reduction in beam losses by more than 90%. The design, implementation and performance is discussed.

Storm Prediction Center - Mesoscale Analysis Pages

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Archive NOAA Weather Radio Research Non-op. Products Forecast Tools Svr. Tstm. Events SPC Publications SPC experimental ESRL RAPv2-based Mesoanalysis fields is no longer available. Summary of changes in March 2012: The

Small bowel injury after suprapubic catheter insertion presenting 3 years after initial insertion

PubMed Central

Gallagher, Kevin M; Good, Daniel W; Brush, John P; Al-hasso, Ammar; Stewart, Grant D

2013-01-01

A 77-year-old woman was referred to urology with blockages of her suprapubic catheter (SPC). The catheter was replaced easily in the emergency department, however, no urine was draining, only a cloudy green fluid was visible. On cystoscopy bilious material was identified in the bladder. There was no catheter visible. There seemed to be a fistulous tract entering the bladder at the left dome. The urethra was dilated, a urethral catheter was placed and the SPC was removed. A CT demonstrated that the SPC tract transfixed a loop of pelvic small bowel and entered the bladder with no intraperitoneal contrast leak. The patient recovered well and did not require laparotomy. This case emphasises that bowel perforation, although rare, must be considered as a complication of SPC placement even years after initial insertion when catheter problems arise. Unusually, we learn that this complication may not present with abdominal pain or peritonism. PMID:24326435

Lightweight Towed Howitzer Demonstrator. Phase 1 and Partial Phase 2. Volume F. Systems Engineering Analysis (QA, Test Plans).

DTIC Science & Technology

1987-04-01

FAIILURE MOVDE SPECMEN LOAD REQ ’D PE (ADHES ION, SPC NO. WI=l ADHESIVE TOD PEEI 5 IN. STRENG COHESION, OR RANZ’IT1= W (IN) THICKESS P (LBS) P/W BASE...area, squat * incries nomina. thickness 9 moeasuced widthl) b - width. measured to ;@&cost 0.00, inch (se T nabnle ht 1117s .31culated Eros nominal...no&na 101ms-sec1ona area. squat LneCes(nooln cno 7:*s-n 4 c nm i tickes., I a (measured Vkdthl f. Tonse Strain Uti .L ,c-o &n./Ln. - See Flbque 4 The

[Pharmacological Basis for Therapeutics. Pharmacological Analysis of Summary of Product Characteristics (SPC) for Physicians].

PubMed

Lechat, Philippe

2015-01-01

The summary of product characteristics, the SPC, is the major annex document of Marketing Authorisation (MA) dossier for a medicine. This document is the reference document for health care professionnals since it contains all necessary and opposable information for its therapeutic use. The SPC is initially submitted by the MA applicant and deeply revised in details by regulatory authorities, the national agencies for national MA, and the European Medicine Agency (EMA) for the european centralized procedures. The SPC presents with 12 sections each one being divided into several paragraphs. Sections 1-3 present the name, dosage, qualitative and quantitative composition, the pharmaceutical form of the medicine. Section 4 contains all the clinical particulars: Therapeutic indications, posology and methods of administration, contra-indications, special warnings and precautions for use, interactions, impact on fertility, contraception, pregnancy, lactation, effects on ability to drive and use machines, undesirable effects and risk associated with overdose. Section 5 describes pharmacological properties (pharmacodynamics and pharmacokinetics) and preclinical safety data. Section 6 describes the pharmaceutical particulars: excipients, incompatibilities, shelf live, nature and content of container, special precautions for disposal. Sections 7-10 are administrative ones (date of MA, MA holder), sections 11 and 12 are specific to radiopharmaceuticals (dosimetry and modalities of preparation). SPC is available free of charge on national regulatory agency websites and on EMA website. Sections of SPC finally have to be considered as the pharmacological basis of therapeutic use for each medicine. © 2015 Société Française de Pharmacologie et de Thérapeutique.

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Archive NOAA Weather Radio Research Non-op. Products Forecast Tools Svr. Tstm. Events SPC Publications SPC hour, and will also re-run old hours to fill in late data. NOTE: This data is experimental and may not

Specialist palliative care services for adults with advanced, incurable illness in hospital, hospice, or community settings--protocol for a systematic review.

PubMed

Gaertner, Jan; Siemens, Waldemar; Antes, Gerd; Meerpohl, Joerg J; Xander, Carola; Schwarzer, Guido; Stock, Stephanie; Becker, Gerhild

2015-09-25

Specialist palliative care (SPC) interventions aim to relieve and prevent suffering in the physical, psychological, social, and spiritual domain. Therefore, SPC is carried out by a multi-professional team with different occupations (e.g., physician, nurse, psychologist, and social worker). Remaining skepticism concerning the need for SPC may be based on the scarcity of high-quality evaluations about the external evidence for SPC. Therefore, we will conduct a systematic review according to Cochrane standards to examine the effects of SPC for adults with advanced illness. The comprehensive systematic literature search will include randomized controlled trials (RCTs) and cluster RCTs. We will search the databases MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), and PsycINFO. Patients must be adults suffering from life-limiting diseases. Proxy and caregiver outcomes will not be assessed in order to ensure a clear and well-defined research question for this review. Interventions may be in an in- or outpatient setting, e.g., consulting service, palliative care ward, and palliative outpatient clinic. In line with the multi-dimensional scope of palliative care, the primary outcome is quality of life (QoL). Key secondary outcomes are patients' symptom burden, place of death and survival, and health economic aspects. Subgroup analysis will assess results according to cancer type, age, early vs not early SPC, site of care, and setting. Analysis will be performed with the current RevMan software. We will use the Cochrane Collaboration risk of bias assessment tool. The quality of evidence will be judged according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. The available evidence will be summarized and discussed to provide a basis for decision-making among health care professionals and policy makers. For SPC, we believe that multi-professional care is of utmost importance. Therefore, single-profession interventions such as physician consultations will not be included. Based on the multi-dimensional scope of palliative care, we chose QoL as the primary outcome, despite an expected heterogeneity among the QoL outcomes. We consider unidimensional endpoints such as "pain" for the physical domain to be inadequate for capturing the true scope of (S)PC (i.e., QoL) as defined by the World Health Organization. PROSPERO CRD42015020674.

Effect of dietary soybean oil and soybean protein concentration on the concentration of digestible amino acids in soybean products fed to growing pigs.

PubMed

Cervantes-Pahm, S K; Stein, H H

2008-08-01

An experiment was conducted to measure the effect of adding soybean oil to soybean meal (SBM) and soy protein concentrate (SPC) on apparent (AID) and standardized (SID) ileal digestibility of CP and AA by growing pigs. A second objective was to compare AID and SID of AA in a new high-protein variety of full fat soybeans (FFSB) to values obtained in other soybean products. Commercial sources of FFSB (FFSB-CV), SBM, and SPC, and of a new high-protein variety of FFSB (FFSB-HP) were used in the experiment. Four diets were prepared using each soybean product as the sole source of CP and AA in 1 diet. Two additional diets were formulated by adding soybean oil (7.55 and 7.35%, respectively) to the diets containing SBM and SPC. A nitrogen-free diet was also used to measure basal endogenous losses of CP and AA. The 2 sources of FFSB were extruded at 150 degrees C before being used in the experiment. Seven growing barrows (initial BW = 26.2 kg) were prepared with a T-cannula in the distal ileum and allotted to a 7 x 7 Latin square design. Ileal digesta were collected from the pigs on d 6 and 7 of each period. All digesta samples were lyophilized and analyzed for DM, CP, AA, and chromium, and values for AID and SID of CP and AA were calculated. The addition of oil improved (P < 0.05) the SID of most indispensable AA in SBM and SPC. The SID for 6 of the indispensable AA in FFSB-HP were greater (P < 0.05) than in FFSB-CV, and the SID for all indispensable AA except Met was greater (P < 0.05) in FFSB-HP than in SBM. However, the SID for most AA in FFSB-HP was similar to SBM with oil and SPC, but these values were lower (P < 0.05) than in SPC with oil. In conclusion, the addition of oil improved the SID of most AA in SBM and SPC fed to growing pigs, and the SID of AA in FFSB-HP were greater than in SBM and similar to the SID of AA in SBM with oil and in SPC.

The 13th Psychological Operations Battalion (EPW) during Mobilization, Desert Shield / Desert Storm and Demobilization

DTIC Science & Technology

1993-05-10

they did not sit, they squatted . They also had a great need for privacy. A modification was made, converting the latrines into a three-hole facility...BRYANT, Cedric SSG FELTON, Mark A. SSG MCQUAID, Daniel A. SSG NUCKLES, Bradley SSG TAYLOR, Ernest K JR SSG GAUL, Robert J. SGT CAIN, William T. SPC ...MCSHANE, Charles A. SPC THOMAS, Timothy L. SPC r Ii rP .I’., . .. ; :; ’, .; ., ., . ’I .If ’’ . Ill TL 5IL LLG •~ ,i:b F--,.,,. ’ 9 1 .... E8~ %F, 4

Potential energy landscape of the apparent first-order phase transition between low-density and high-density amorphous ice.

PubMed

Giovambattista, Nicolas; Sciortino, Francesco; Starr, Francis W; Poole, Peter H

2016-12-14

The potential energy landscape (PEL) formalism is a valuable approach within statistical mechanics to describe supercooled liquids and glasses. Here we use the PEL formalism and computer simulations to study the pressure-induced transformations between low-density amorphous ice (LDA) and high-density amorphous ice (HDA) at different temperatures. We employ the ST2 water model for which the LDA-HDA transformations are remarkably sharp, similar to what is observed in experiments, and reminiscent of a first-order phase transition. Our results are consistent with the view that LDA and HDA configurations are associated with two distinct regions (megabasins) of the PEL that are separated by a potential energy barrier. At higher temperature, we find that low-density liquid (LDL) configurations are located in the same megabasin as LDA, and that high-density liquid (HDL) configurations are located in the same megabasin as HDA. We show that the pressure-induced LDL-HDL and LDA-HDA transformations occur along paths that interconnect these two megabasins, but that the path followed by the liquid is different from the path followed by the amorphous solid. At higher pressure, we also study the liquid-to-ice-VII first-order phase transition, and find that the behavior of the PEL properties across this transition is qualitatively similar to the changes found during the LDA-HDA transformation. This similarity supports the interpretation that the LDA-HDA transformation is a first-order phase transition between out-of-equilibrium states. Finally, we compare the PEL properties explored during the LDA-HDA transformations in ST2 water with those reported previously for SPC/E water, for which the LDA-HDA transformations are rather smooth. This comparison illuminates the previous work showing that, at accessible computer times scales, a liquid-liquid phase transition occurs in the case of ST2 water, but not for SPC/E water.

Potential energy landscape of the apparent first-order phase transition between low-density and high-density amorphous ice

NASA Astrophysics Data System (ADS)

Giovambattista, Nicolas; Sciortino, Francesco; Starr, Francis W.; Poole, Peter H.

2016-12-01

The potential energy landscape (PEL) formalism is a valuable approach within statistical mechanics to describe supercooled liquids and glasses. Here we use the PEL formalism and computer simulations to study the pressure-induced transformations between low-density amorphous ice (LDA) and high-density amorphous ice (HDA) at different temperatures. We employ the ST2 water model for which the LDA-HDA transformations are remarkably sharp, similar to what is observed in experiments, and reminiscent of a first-order phase transition. Our results are consistent with the view that LDA and HDA configurations are associated with two distinct regions (megabasins) of the PEL that are separated by a potential energy barrier. At higher temperature, we find that low-density liquid (LDL) configurations are located in the same megabasin as LDA, and that high-density liquid (HDL) configurations are located in the same megabasin as HDA. We show that the pressure-induced LDL-HDL and LDA-HDA transformations occur along paths that interconnect these two megabasins, but that the path followed by the liquid is different from the path followed by the amorphous solid. At higher pressure, we also study the liquid-to-ice-VII first-order phase transition, and find that the behavior of the PEL properties across this transition is qualitatively similar to the changes found during the LDA-HDA transformation. This similarity supports the interpretation that the LDA-HDA transformation is a first-order phase transition between out-of-equilibrium states. Finally, we compare the PEL properties explored during the LDA-HDA transformations in ST2 water with those reported previously for SPC/E water, for which the LDA-HDA transformations are rather smooth. This comparison illuminates the previous work showing that, at accessible computer times scales, a liquid-liquid phase transition occurs in the case of ST2 water, but not for SPC/E water.

Reactive Oxygen Species Inactivation of Surfactant Involves Structural and Functional Alterations to Surfactant Proteins SP-B and SP-C

PubMed Central

Rodríguez-Capote, Karina; Manzanares, Dahis; Haines, Thomas; Possmayer, Fred

2006-01-01

Exposing bovine lipid extract surfactant (BLES), a clinical surfactant, to reactive oxygen species arising from hypochlorous acid or the Fenton reaction resulted in an increase in lipid (conjugated dienes, lipid aldehydes) and protein (carbonyls) oxidation products and a reduction in surface activity. Experiments where oxidized phospholipids (PL) were mixed with BLES demonstrated that this addition hampered BLES biophysical activity. However the effects were only moderately greater than with control PL. These results imply a critical role for protein oxidation. BLES oxidation by either method resulted in alterations in surfactant proteins SP-B and SP-C, as evidenced by altered Coomassie blue and silver staining. Western blot analyses showed depressed reactivity with specific antibodies. Oxidized SP-C showed decreased palmitoylation. Reconstitution experiments employing PL, SP-B, and SP-C isolated from control or oxidized BLES demonstrated that protein oxidation was more deleterious than lipid oxidation. Furthermore, addition of control SP-B can improve samples containing oxidized SP-C, but not vice versa. We conclude that surfactant oxidation arising from reactive oxygen species generated by air pollution or leukocytes interferes with surfactant function through oxidation of surfactant PL and proteins, but that protein oxidation, in particular SP-B modification, produces the major deleterious effects. PMID:16443649

Tumor Uptake And Photodynamic Activity Of Sulfonated Metallo Phthalocyanines

NASA Astrophysics Data System (ADS)

van Lier, Johan E.; Rousseau, Jacques; Paquette, Benoit; Brasseur, N.; Langlois, Rejean; Ali, Hasrat

1989-06-01

Sulfonated metallo phthalocyanines (M-SPC) are extensively studied as sensitizers for photodynamic therapy of cancer. They strongly absorb clinically useful red light with absorption maxima between 670-680 nm. Their photodynamic properties depend on the nature of the central metal ion as well as the degree of substitution on the macrocycle. The zinc, aluminum and gallium complexes are efficient photo-generators of singlet oxygen, the species most likely responsible for their phototoxicity and tumoricidal action. Tissue distribution pattern, cell penetration and dye aggregation are strongly affected by the degree of sulfonation of the dyes. Mono- and disulfonated M-SPC have the highest tendency to form photo-inactive aggregates. However, these lower sulfonated dyes more readily cross cell membranes resulting, in vitro, in enhanced phototoxicity. In vivo, the highly sulfonated hydrophilic M-SPC show the best tumor localization properties but the lower sulfonated dyes still exhibit the best photo-activity. Variations in activities between the differently sulfonated M-SPC are far less pronounced in vivo as compared to in vitro conditions. Such discrepancies are explained by the combined action of numerous vectors including interaction of M-SPC with plasma proteins, vascular versus cellular photo-damage, tumor retention, cell penetration as well as the degree of aggregation of the dye.

Phosphoregulation of Spc105 by Mps1 and PP1 regulates Bub1 localization to kinetochores.

PubMed

London, Nitobe; Ceto, Steven; Ranish, Jeffrey A; Biggins, Sue

2012-05-22

Kinetochores are the macromolecular complexes that interact with microtubules to mediate chromosome segregation. Accurate segregation requires that kinetochores make bioriented attachments to microtubules from opposite poles. Attachments between kinetochores and microtubules are monitored by the spindle checkpoint, a surveillance system that prevents anaphase until every pair of chromosomes makes proper bioriented attachments. Checkpoint activity is correlated with the recruitment of checkpoint proteins to the kinetochore. Mps1 is a conserved protein kinase that regulates segregation and the spindle checkpoint, but few of the targets that mediate its functions have been identified. Here, we show that Mps1 is the major kinase activity that copurifies with budding yeast kinetochore particles and identify the conserved Spc105/KNL-1/blinkin kinetochore protein as a substrate. Phosphorylation of conserved MELT motifs within Spc105 recruits the Bub1 protein to kinetochores, and this is reversed by protein phosphatase I (PP1). Spc105 mutants lacking Mps1 phosphorylation sites are defective in the spindle checkpoint and exhibit growth defects. Together, these data identify Spc105 as a key target of the Mps1 kinase and show that the opposing activities of Mps1 and PP1 regulate the kinetochore localization of the Bub1 protein. Copyright © 2012 Elsevier Ltd. All rights reserved.

Strontium enhances osseointegration of calcium phosphate cement: a histomorphometric pilot study in ovariectomized rats.

PubMed

Baier, Martin; Staudt, Patric; Klein, Roman; Sommer, Ulrike; Wenz, Robert; Grafe, Ingo; Meeder, Peter Jürgen; Nawroth, Peter P; Kasperk, Christian

2013-06-07

Calcium phosphate cements are used frequently in orthopedic and dental surgeries. Strontium-containing drugs serve as systemic osteoblast-activating medication in various clinical settings promoting mechanical stability of the osteoporotic bone. Strontium-containing calcium phosphate cement (SPC) and calcium phosphate cement (CPC) were compared regarding their local and systemic effects on bone tissue in a standard animal model for osteoporotic bone. A bone defect was created in the distal femoral metaphysis of 60 ovariectomized Sprague-Dawley rats. CPC and SPC were used to fill the defects in 30 rats in each group. Local effects were assessed by histomorphometry at the implant site. Systemic effects were assessed by bone mineral density (BMD) measurements at the contralateral femur and the spine. Faster osseointegration and more new bone formation were found for SPC as compared to CPC implant sites. SPC implants exhibited more cracks than CPC implants, allowing more bone formation within the implant. Contralateral femur BMD and spine BMD did not differ significantly between the groups. The addition of strontium to calcium phosphate stimulates bone formation in and around the implant. Systemic release of strontium from the SPC implants did not lead to sufficiently high serum strontium levels to induce significant systemic effects on bone mass in this rat model.

Challenges in defining 'palliative care' for the purposes of clinical trials.

PubMed

Bausewein, Claudia; Higginson, Irene J

2012-12-01

Palliative care has become part of mainstream medicine with increasing evidence about the effectiveness of specialist palliative care (SPC) on patient and family outcomes. Comparison of studies testing SPC interventions is challenging as types of interventions and reporting of components of the intervention vary. In consequence, study results are difficult to interpret. There is a continuous lack of clarity in palliative care definitions. For clinical trials, multidisciplinary care, supportive care documentation, symptom assessment and symptom management are suggested as key domains. In recent studies testing palliative care as an intervention SPC physicians and palliative care nurses were core members of multiprofessional teams, but integration of other team members varied. Management of symptoms and psychosocial issues were central to SPC with various other areas described. Services were delivered by hospital and community support teams, in palliative care units, outpatient clinics and hospital. Cost information was only provided by a few studies. Due to the lack of an agreed definition of palliative care and heterogeneity in reporting of components of an SPC intervention comparison of studies remains challenging. Key aspects of palliative care interventions are incurable disease, multidisciplinary approach, focus on symptom management including standardized assessment, psychosocial and family support, and (advance) care planning. Detailed information about all aspects of the intervention should be provided.

Joint and independent effect of alcohol and tobacco use on the risk of subsequent cancer incidence among cancer survivors: A cohort study using cancer registries.

PubMed

Tabuchi, Takahiro; Ozaki, Koken; Ioka, Akiko; Miyashiro, Isao

2015-11-01

Drinking alcohol and smoking tobacco are major modifiable risk factors for cancer. However, little is known about whether these modifiable factors of cancer survivors are associated with subsequent primary cancer (SPC) incidence, regardless of the first cancer sites. 27,762 eligible cancer survivors diagnosed between 1985 and 2007 were investigated for SPC until the end of 2008, using hospital-based and population-based cancer registries. The association between drinking, smoking and combined drinking and smoking (interaction) at the time of the first cancer diagnosis and incidence of SPCs (i.e., all SPCs, alcohol-related, smoking-related and specific SPCs) was estimated by Poisson regression. Compared with never-drinker/never-smoker, the categories ever-drinker/ever-smoker, current-drinker/current-smoker and heavy-drinker/heavy-smoker had 43-108%, 51-126% and 167-299% higher risk for all, alcohol-related and tobacco-related SPCs, respectively. The interaction of drinking and smoking had significantly high incidence rate ratios (IRRs) for SPCs among ever-drinker/ever-smoker and current-drinker/current-smoker, although ever drinking did not show a significant risk. Ever-drinker/ever-smoker had also significantly higher IRRs for esophageal and lung SPCs than never-drinker/never-smoker. Among comprehensive cancer survivors, ever and current drinkers only had a SPC risk when combined with smoking, while ever and current smokers had a SPC risk regardless of drinking status. Heavy drinking and heavy smoking were considered to be independent additive SPC risk factors. To reduce SPC incidence, it may be necessary (i) to reduce or stop alcohol use, (ii) to stop tobacco smoking and (iii) dual users, especially heavy users, should be treated as a high-risk population for behavioral-change intervention. © 2015 UICC.

[Palliative care for patients with Turkish or Arabic migration background in Lower Saxony : A survey from palliative care professionals' perspective].

PubMed

Jansky, Maximiliane; Owusu-Boakye, Sonja; Nauck, Friedemann

2017-01-01

People with a migration background (MB) are an important part of German society. If and how they use specialised palliative care (SPC) has not been studied. We aimed to assess the current SPC for patients with Turkish or Arabic MB (the largest group of immigrants in Germany with a shared ascribed culture) from the point of view of healthcare professionals (HCP) in Lower Saxony. All HCPs in institutions providing SPC (n = 90) were invited to participate in an anonymous online survey which contained closed and open questions about care for this patient group, characteristics of the last patient with Turkish or Arabic MB they cared for, and resources and strategies to care for these patients. The survey was analysed using descriptive statistics and qualitative content analysis. Fifty-five HCPs in SPC participated, mostly nurses aged between 40 and 60 years. One fifth had not cared for a patient with Turkish or Arabic MB during the last 12 months. Given their local population, 84.6% estimated that they cared for a lower number of patients than would be representative. In care, problems with communication as well as difficulties to interact with and manage families, and in organising and planning care were most prevalent. Only 21% of participants had access to interpreters. Patients with Turkish or Arabic MB seem to be underrepresented in SPC. The high rate of communication problems highlights the necessity of reliable and accessible interpreter services. Most difficulties were of psychosocial nature, showing how important the holistic approach of SPC is in caring for terminally ill patients with Turkish or Arabic MB.

The Mps1 kinase modulates the recruitment and activity of Cnn1(CENP-T) at Saccharomyces cerevisiae kinetochores.

PubMed

Thapa, Kriti Shrestha; Oldani, Amanda; Pagliuca, Cinzia; De Wulf, Peter; Hazbun, Tony R

2015-05-01

Kinetochores are conserved protein complexes that bind the replicated chromosomes to the mitotic spindle and then direct their segregation. To better comprehend Saccharomyces cerevisiae kinetochore function, we dissected the phospho-regulated dynamic interaction between conserved kinetochore protein Cnn1(CENP-T), the centromere region, and the Ndc80 complex through the cell cycle. Cnn1 localizes to kinetochores at basal levels from G1 through metaphase but accumulates abruptly at anaphase onset. How Cnn1 is recruited and which activities regulate its dynamic localization are unclear. We show that Cnn1 harbors two kinetochore-localization activities: a C-terminal histone-fold domain (HFD) that associates with the centromere region and a N-terminal Spc24/Spc25 interaction sequence that mediates linkage to the microtubule-binding Ndc80 complex. We demonstrate that the established Ndc80 binding site in the N terminus of Cnn1, Cnn1(60-84), should be extended with flanking residues, Cnn1(25-91), to allow near maximal binding affinity to Ndc80. Cnn1 localization was proposed to depend on Mps1 kinase activity at Cnn1-S74, based on in vitro experiments demonstrating the Cnn1-Ndc80 complex interaction. We demonstrate that from G1 through metaphase, Cnn1 localizes via both its HFD and N-terminal Spc24/Spc25 interaction sequence, and deletion or mutation of either region results in anomalous Cnn1 kinetochore levels. At anaphase onset (when Mps1 activity decreases) Cnn1 becomes enriched mainly via the N-terminal Spc24/Spc25 interaction sequence. In sum, we provide the first in vivo evidence of Cnn1 preanaphase linkages with the kinetochore and enrichment of the linkages during anaphase. Copyright © 2015 by the Genetics Society of America.

An atypical proprotein convertase in Giardia lamblia differentiation.

PubMed

Davids, B J; Gilbert, M A; Liu, Q; Reiner, D S; Smith, A J; Lauwaet, T; Lee, C; McArthur, A G; Gillin, F D

2011-02-01

Proteolytic activity is important in the lifecycles of parasites and their interactions with hosts. Cysteine proteases have been best studied in Giardia, but other protease classes have been implicated in growth and/or differentiation. In this study, we employed bioinformatics to reveal the complete set of putative proteases in the Giardia genome. We identified 73 peptidase homologs distributed over 5 catalytic classes in the genome. Serial analysis of gene expression of the G. lamblia lifecycle found thirteen protease genes with significant transcriptional variation over the lifecycle, with only one serine protease transcript upregulated late in encystation. The translated gene sequence of this encystation-specific transcript was most similar to eukaryotic subtilisin-like proprotein convertases (SPC), although the typical catalytic triad was not identified. Epitope-tagged gSPC protein expressed in Giardia under its own promoter was upregulated during encystation with highest expression in cysts and it localized to encystation-specific secretory vesicles (ESV). Total gSPC from encysting cells produced proteolysis in gelatin gels that co-migrated with the epitope-tagged protease in immunoblots. Immuno-purified gSPC also had gelatinase activity. To test whether endogenous gSPC activity is involved in differentiation, trophozoites and cysts were exposed to the specific serine proteinase inhibitor 4-(2-aminoethyl)-benzenesulfonyl fluoride hydrochloride (AEBSF). After 21 h encystation, a significant decrease in ESV was observed with 1mM AEBSF and by 42 h the number of cysts was significantly reduced, but trophozoite growth was not inhibited. Concurrently, levels of cyst wall proteins 1 and 2, and AU1-tagged gSPC protein itself were decreased. Excystation of G. muris cysts was also significantly reduced in the presence of AEBSF. These results support the idea that serine protease activity is essential for Giardia encystation and excystation. Copyright © 2010 Elsevier B.V. All rights reserved.

An Atypical Proprotein Convertase in Giardia lamblia Differentiation

PubMed Central

Davids, B. J.; Gilbert, M. A.; Liu, Q.; Reiner, D. S.; Smith, A. J.; Lauwaet, T.; Lee, C.; McArthur, A. G.; Gillin, F. D.

2010-01-01

Proteolytic activity is important in the lifecycles of parasites and their interactions with hosts. Cysteine proteases have been best studied in Giardia, but other protease classes have been implicated in growth and/or differentiation. In this study, we employed bioinformatics to reveal the complete set of putative proteases in the Giardia genome. We identified 73 peptidase homologues distributed over 5 catalytic classes in the genome. Serial analysis of gene expression of the G. lamblia lifecycle found thirteen protease genes with significant transcriptional variation over the lifecycle, with only one serine protease transcript upregulated late in encystation. The translated gene sequence of this encystation-specific transcript was most similar to eukaryotic subtilisin-like proprotein convertases (SPC), although the typical catalytic triad was not identified. Epitope-tagged gSPC protein expressed in Giardia under its own promoter was upregulated during encystation with highest expression in cysts and it localized to encystation-specific secretory vesicles (ESV). Total gSPC from encysting cells produced proteolysis in gelatin gels that co-migrated with the epitope-tagged protease in immunoblots. Immuno-purified gSPC also had gelatinase activity. To test whether endogenous gSPC activity is involved in differentiation, trophozoites and cysts were exposed to the specific serine proteinase inhibitor 4-(2-Aminoethyl)-benzenesulfonyl fluoride hydrochloride (AEBSF). After 21 h encystation, a significant decrease in ESV was observed with 1 mM AEBSF and by 42 h the number of cysts was significantly reduced, but trophozoite growth was not inhibited. Concurrently, levels of cyst wall proteins 1 and 2, and AU1-tagged gSPC protein itself were decreased. Excystation of G. muris cysts was also significantly reduced in the presence of AEBSF. These results support the idea that serine protease activity is essential for Giardia encystation and excystation. PMID:21075147

Pulmonary surfactant protein C containing lipid films at the air-water interface as a model for the surface of lung alveoli.

PubMed

Post, A; Nahmen, A V; Schmitt, M; Ruths, J; Riegler, H; Sieber, M; Galla, H J

1995-01-01

The pulmonary surfactant lines as a complex monolayer of lipids and proteins the alveolar epithelial surface. The monolayer dynamically adapts the surface tension of this interface to the varying surface areas during inhalation and exhalation. Its presence in the alveoli is thus a prerequisite for a proper lung function. The lipid moiety represents about 90% of the surfactant and contains mainly dipalmitoylphosphatidylcholine (DPPC) and phosphatidylglycerol (PG). The surfactant proteins involved in the surface tension adaption are called SP-A, SP-B and SP-C. The aim of the present investigation is to analyse the properties of monolayer films made from pure SP-C and from mixtures of DPPC, DPPG and SP-C in order to mimic the surfactant monolayer with minimal compositional requirement. Pressure-area diagrams were taken. Ellipsometric measurements at the air-water interface of a Langmuir film balance allowed measurement of the changes in monolayer thickness upon compression. Isotherms of pure SP-C monolayers exhibit a plateau between 22 and 25 mN/m. A further plateau is reached at higher compression. Structures of the monolayer formed during compression are reversible during expansion. Together with ellipsometric data which show a stepwise increase in film thickness (coverage) during compression, we conclude that pure SP-C films rearrange reversibly into multilayers of homogenous thickness. Lipid monolayers collapse locally and irreversibly if films are compressed to approximately 0.4 nm2/molecule. In contrast, mixed DPPG/SP-C monolayers with less than 5 mol% protein collapse in a controlled and reversible way. The pressure-area diagrams exhibit a plateau at 20 mN/m, indicating partial demixing of SP-C and DPPG.(ABSTRACT TRUNCATED AT 250 WORDS)

Soybean protein-based microparticles for oral delivery of probiotics with improved stability during storage and gut resistance.

PubMed

González-Ferrero, C; Irache, J M; González-Navarro, C J

2018-01-15

The present work describes the encapsulation of probiotics using a by-product as wall material and a process feasible to be scaled-up: coacervation of soybean protein concentrate (SPC) by using calcium salts and spray-drying. SPC was extracted from soybean flour, produced during the processing of soybean milk, by alkaline extraction following isoelectric precipitation. Two probiotic strains were selected for encapsulation (Lactobacillus plantarum CECT 220 and Lactobacillus casei CECT 475) in order to evaluate the ability of SPC to encapsulate and protect bacteria from stress conditions. The viability of these encapsulated strains under in vitro gastrointestinal conditions and shelf-life during storage were compared with the most common forms commercialized nowadays. Results show that SPC is a feasible material for the development of probiotic microparticles with adequate physicochemical properties and enhanced significantly both probiotic viability and tolerance against simulated gastrointestinal fluids when compared to current available commercial forms. Copyright © 2017 Elsevier Ltd. All rights reserved.

Characterization of a sustainable sulfur polymer concrete using activated fillers

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

Moon, Juhyuk; Kalb, Paul D.; Milian, Laurence

Sulfur polymer concrete (SPC) is a thermoplastic composite concrete consisting of chemically modified sulfur polymer and aggregates. This study focused on the characterization of a new SPC that has been developed as a sustainable construction material. It is made from industrial by-product sulfur that is modified with activated fillers of fly ash, petroleum refinery residual oil, and sand. Unlike conventional sulfur polymer cements made using dicyclopentadiene as a chemical modifier, the use of inexpensive industrial by-products enables the new SPC to cost-effectively produce sustainable, low-carbon, thermoplastic binder that can compete with conventional hydraulic cement concretes. A series of characterization analysesmore » was conducted including thermal analysis, X-ray diffraction, and spatially-resolved Xray absorption spectroscopy to confirm the polymerization of sulfur induced from the presence of the oil. In addition, mechanical testing, internal pore structure analysis, and scanning electron microscope studies evaluate the performance of this new SPC as a sustainable construction material with a reduced environmental impact.« less

Light field geometry of a Standard Plenoptic Camera.

PubMed

Hahne, Christopher; Aggoun, Amar; Haxha, Shyqyri; Velisavljevic, Vladan; Fernández, Juan Carlos Jácome

2014-11-03

The Standard Plenoptic Camera (SPC) is an innovation in photography, allowing for acquiring two-dimensional images focused at different depths, from a single exposure. Contrary to conventional cameras, the SPC consists of a micro lens array and a main lens projecting virtual lenses into object space. For the first time, the present research provides an approach to estimate the distance and depth of refocused images extracted from captures obtained by an SPC. Furthermore, estimates for the position and baseline of virtual lenses which correspond to an equivalent camera array are derived. On the basis of paraxial approximation, a ray tracing model employing linear equations has been developed and implemented using Matlab. The optics simulation tool Zemax is utilized for validation purposes. By designing a realistic SPC, experiments demonstrate that a predicted image refocusing distance at 3.5 m deviates by less than 11% from the simulation in Zemax, whereas baseline estimations indicate no significant difference. Applying the proposed methodology will enable an alternative to the traditional depth map acquisition by disparity analysis.

Effects of Fundamental Movement Skills Training on Children With Developmental Coordination Disorder.

PubMed

Yu, Jie; Sit, Cindy H; Burnett, Angus; Capio, Catherine M; Ha, Amy S; Huang, Wendy Y

2016-04-01

The purpose of this study was to examine the effects of fundamental movement skills (FMS) training on FMS proficiency, self-perceived physical competence (SPC), physical activity (PA), and sleep disturbance in children with developmental coordination disorder (DCD) compared with children with typical development (TD). A total of 84 children were allocated into either experimental group (DCD[exp], TD[exp]) who received 6 weeks of FMS training or control groups (DCD[con], TD[con]). FMS were assessed using the Test of Gross Motor Development-2, whereas PA was monitored using accelerometers. SPC and sleep disturbance were evaluated using questionnaires. Results showed that the DCD[exp] group had significantly higher scores in FMS and SPC compared with the DCD[con] group at posttest. The DCD[exp] group scored lower in sleep disturbance at follow-up when compared with posttest. It is suggested that short-term FMS training is effective in improving FMS and SPC and reducing sleep disturbances for children with DCD.

Characterization of a sustainable sulfur polymer concrete using activated fillers

DOE PAGES

Moon, Juhyuk; Kalb, Paul D.; Milian, Laurence; ...

2016-01-02

Sulfur polymer concrete (SPC) is a thermoplastic composite concrete consisting of chemically modified sulfur polymer and aggregates. This study focused on the characterization of a new SPC that has been developed as a sustainable construction material. It is made from industrial by-product sulfur that is modified with activated fillers of fly ash, petroleum refinery residual oil, and sand. Unlike conventional sulfur polymer cements made using dicyclopentadiene as a chemical modifier, the use of inexpensive industrial by-products enables the new SPC to cost-effectively produce sustainable, low-carbon, thermoplastic binder that can compete with conventional hydraulic cement concretes. A series of characterization analysesmore » was conducted including thermal analysis, X-ray diffraction, and spatially-resolved Xray absorption spectroscopy to confirm the polymerization of sulfur induced from the presence of the oil. In addition, mechanical testing, internal pore structure analysis, and scanning electron microscope studies evaluate the performance of this new SPC as a sustainable construction material with a reduced environmental impact.« less

Laboratory and On-sky Validation of the Shaped Pupil Coronagraph’s Sensitivity to Low-order Aberrations With Active Wavefront Control

NASA Astrophysics Data System (ADS)

Currie, Thayne; Kasdin, N. Jeremy; Groff, Tyler D.; Lozi, Julien; Jovanovic, Nemanja; Guyon, Olivier; Brandt, Timothy; Martinache, Frantz; Chilcote, Jeffrey; Skaf, Nour; Kuhn, Jonas; Pathak, Prashant; Kudo, Tomoyuki

2018-04-01

We present early laboratory simulations and extensive on-sky tests validating of the performance of a shaped pupil coronagraph (SPC) behind an extreme-AO corrected beam of the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) system. In tests with the SCExAO internal source/wavefront error simulator, the normalized intensity profile for the SPC degrades more slowly than for the Lyot coronagraph as low-order aberrations reduce the Strehl ratio from extremely high values (S.R. ∼ 0.93–0.99) to those characteristic of current ground-based extreme AO systems (S.R. ∼ 0.74–0.93) and then slightly lower values down to S.R. ∼ 0.57. On-sky SCExAO data taken with the SPC and other coronagraphs for brown dwarf/planet-hosting stars HD 1160 and HR 8799 provide further evidence for the SPC’s robustness to low-order aberrations. From H-band Strehl ratios of 80% to 70%, the Lyot coronagraph’s performance versus that of the SPC may degrade even faster on sky than is seen in our internal source simulations. The 5-σ contrast also degrades faster (by a factor of two) for the Lyot than the SPC. The SPC we use was designed as a technology demonstrator only, with a contrast floor, throughput, and outer working angle poorly matched for SCExAO’s current AO performance and poorly tuned for imaging the HR 8799 planets. Nevertheless, we detect HR 8799 cde with SCExAO/CHARIS using the SPC in broadband mode, where the S/N for planet e is within 30% of that obtained using the vortex coronagraph. The shaped-pupil coronagraph is a promising design demonstrated to be robust in the presence of low-order aberrations and may be well-suited for future ground and space-based direct imaging observations, especially those focused on follow-up exoplanet characterization and technology demonstration of deep contrast within well-defined regions of the image plane.

Growth performance, carcass characteristics and bioavailability of isoflavones in pigs fed soy bean based diets.

PubMed

Kuhn, Gerda; Hennig, U; Kalbe, Claudia; Rehfeldt, Charlotte; Ren, M Q; Moors, S; Degen, Gisela H

2004-08-01

A growth trial with 38 weaners (castrated male pigs) was designed to compare the growth performance and carcass quality of pigs fed diets containing either soy bean meal or soy protein concentrate in a pair-feeding design. Soy bean meal (SBM) and soy protein concentrate (SPC) differed in isoflavone (daidzein plus genistein) content (782 microg/g in SBM and 125 microg/g in SPC, respectively). During the experiment, all pigs were fed four-phases-diets characterized by decreasing protein concentrations with increasing age (weaner I, weaner II, grower, finisher diets). Rations of control and experimental groups were isoenergetic, isonitrogenous, and isoaminogen. The weanling pigs with an initial live weight of 8.4 +/- 1.1 kg were allotted to flat deck boxes. During the growing/finishing period (days 70-170 of age), the pigs were housed in single boxes. Both, the weaning and the grower/finishing performances (daily body weight gain, feed intake, feed conversion ratio) were similar in both groups. No differences were found between the groups in carcass composition (percentages of cuts, tissues, and protein/fat), and meat quality of pigs. Moreover, the IGF-1R mRNA expression in longissimus muscle was not influenced by the kind of soy product. However, circulating levels of isoflavones were clearly different between pigs fed SBM (genistein 239 +/- 44; daidzein 162 +/- 42; equol 12 +/- 4 ng/ml plasma) and animals fed SPC (genistein 22 +/- 9 and daidzein 8 +/- 3, and equol 10 +/- 3 ng/ml plasma). The results confirm the expected differences in the bioavailability of soy isoflavones, yet, there were no significant differences in performance of pigs fed either soy bean meal or soy protein concentrate.

Closing the contrast gap between testbed and model prediction with WFIRST-CGI shaped pupil coronagraph

NASA Astrophysics Data System (ADS)

Zhou, Hanying; Nemati, Bijan; Krist, John; Cady, Eric; Prada, Camilo M.; Kern, Brian; Poberezhskiy, Ilya

2016-07-01

JPL has recently passed an important milestone in its technology development for a proposed NASA WFIRST mission coronagraph: demonstration of better than 1x10-8 contrast over broad bandwidth (10%) on both shaped pupil coronagraph (SPC) and hybrid Lyot coronagraph (HLC) testbeds with the WFIRST obscuration pattern. Challenges remain, however, in the technology readiness for the proposed mission. One is the discrepancies between the achieved contrasts on the testbeds and their corresponding model predictions. A series of testbed diagnoses and modeling activities were planned and carried out on the SPC testbed in order to close the gap. A very useful tool we developed was a derived "measured" testbed wavefront control Jacobian matrix that could be compared with the model-predicted "control" version that was used to generate the high contrast dark hole region in the image plane. The difference between these two is an estimate of the error in the control Jacobian. When the control matrix, which includes both amplitude and phase, was modified to reproduce the error, the simulated performance closely matched the SPC testbed behavior in both contrast floor and contrast convergence speed. This is a step closer toward model validation for high contrast coronagraphs. Further Jacobian analysis and modeling provided clues to the possible sources for the mismatch: DM misregistration and testbed optical wavefront error (WFE) and the deformable mirror (DM) setting for correcting this WFE. These analyses suggested that a high contrast coronagraph has a tight tolerance in the accuracy of its control Jacobian. Modifications to both testbed control model as well as prediction model are being implemented, and future works are discussed.

Faculty Return to Industry. Final Report.

ERIC Educational Resources Information Center

Hulse, David R.

Lagging productivity and increased competitiveness from abroad are forcing U.S. management companies to adopt new management styles that promote efficiency and quality in production. High on the agenda is the incorporation of Statistical Process Control (SPC). SPC requires definition of process and product specifications to facilitate their…

Assessment of the application of an automated electronic milk analyzer for the enumeration of total bacteria in raw goat milk.

PubMed

Ramsahoi, L; Gao, A; Fabri, M; Odumeru, J A

2011-07-01

Automated electronic milk analyzers for rapid enumeration of total bacteria counts (TBC) are widely used for raw milk testing by many analytical laboratories worldwide. In Ontario, Canada, Bactoscan flow cytometry (BsnFC; Foss Electric, Hillerød, Denmark) is the official anchor method for TBC in raw cow milk. Penalties are levied at the BsnFC equivalent level of 50,000 cfu/mL, the standard plate count (SPC) regulatory limit. This study was conducted to assess the BsnFC for TBC in raw goat milk, to determine the mathematical relationship between the SPC and BsnFC methods, and to identify probable reasons for the difference in the SPC:BsnFC equivalents for goat and cow milks. Test procedures were conducted according to International Dairy Federation Bulletin guidelines. Approximately 115 farm bulk tank milk samples per month were tested for inhibitor residues, SPC, BsnFC, psychrotrophic bacteria count, composition (fat, protein, lactose, lactose and other solids, and freezing point), and somatic cell count from March 2009 to February 2010. Data analysis of the results for the samples tested indicated that the BsnFC method would be a good alternative to the SPC method, providing accurate and more precise results with a faster turnaround time. Although a linear regression model showed good correlation and prediction, tests for linearity indicated that the relationship was linear only beyond log 4.1 SPC. The logistic growth curve best modeled the relationship between the SPC and BsnFC for the entire sample population. The BsnFC equivalent to the SPC 50,000 cfu/mL regulatory limit was estimated to be 321,000 individual bacteria count (ibc)/mL. This estimate differs considerably from the BsnFC equivalent for cow milk (121,000 ibc/mL). Because of the low frequency of bulk tank milk pickups at goat farms, 78.5% of the samples had their oldest milking in the tank to be 6.5 to 9.0 d old when tested, compared with the cow milk samples, which had their oldest milking at 4 d old when tested. This may be one of the major factors contributing to the larger goat milk BsnFC equivalence. Correlations and interactions between various test results were also discussed to further understand differences between the 2 methods for goat and cow milks. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Single cell digital polymerase chain reaction on self-priming compartmentalization chip

PubMed Central

Zhu, Qiangyuan; Qiu, Lin; Xu, Yanan; Li, Guang; Mu, Ying

2017-01-01

Single cell analysis provides a new framework for understanding biology and disease, however, an absolute quantification of single cell gene expression still faces many challenges. Microfluidic digital polymerase chain reaction (PCR) provides a unique method to absolutely quantify the single cell gene expression, but only limited devices are developed to analyze a single cell with detection variation. This paper describes a self-priming compartmentalization (SPC) microfluidic digital polymerase chain reaction chip being capable of performing single molecule amplification from single cell. The chip can be used to detect four single cells simultaneously with 85% of sample digitization. With the optimized protocol for the SPC chip, we first tested the ability, precision, and sensitivity of our SPC digital PCR chip by assessing β-actin DNA gene expression in 1, 10, 100, and 1000 cells. And the reproducibility of the SPC chip is evaluated by testing 18S rRNA of single cells with 1.6%–4.6% of coefficient of variation. At last, by detecting the lung cancer related genes, PLAU gene expression of A549 cells at the single cell level, the single cell heterogeneity was demonstrated. So, with the power-free, valve-free SPC chip, the gene copy number of single cells can be quantified absolutely with higher sensitivity, reduced labor time, and reagent. We expect that this chip will enable new studies for biology and disease. PMID:28191267

Single-step assembly of polymer-lipid hybrid nanoparticles for mitomycin C delivery

PubMed Central

2014-01-01

Mitomycin C is one of the most effective chemotherapeutic agents for a wide spectrum of cancers, but its clinical use is still hindered by the mitomycin C (MMC) delivery systems. In this study, the MMC-loaded polymer-lipid hybrid nanoparticles (NPs) were prepared by a single-step assembly (ACS Nano 2012, 6:4955 to 4965) of MMC-soybean phosphatidyhlcholine (SPC) complex (Mol. Pharmaceutics 2013, 10:90 to 101) and biodegradable polylactic acid (PLA) polymers for intravenous MMC delivery. The advantage of the MMC-SPC complex on the polymer-lipid hybrid NPs was that MMC-SPC was used as a structural element to offer the integrity of the hybrid NPs, served as a drug preparation to increase the effectiveness and safety and control the release of MMC, and acted as an emulsifier to facilitate and stabilize the formation. Compared to the PLA NPs/MMC, the PLA NPs/MMC-SPC showed a significant accumulation of MMC in the nuclei as the action site of MMC. The PLA NPs/MMC-SPC also exhibited a significantly higher anticancer effect compared to the PLA NPs/MMC or free MMC injection in vitro and in vivo. These results suggested that the MMC-loaded polymer-lipid hybrid NPs might be useful and efficient drug delivery systems for widening the therapeutic window of MMC and bringing the clinical use of MMC one step closer to reality. PMID:25324707

Poster - Thur Eve - 29: Detecting changes in IMRT QA using statistical process control.

PubMed

Drever, L; Salomons, G

2012-07-01

Statistical process control (SPC) methods were used to analyze 239 measurement based individual IMRT QA events. The selected IMRT QA events were all head and neck (H&N) cases with 70Gy in 35 fractions, and all prostate cases with 76Gy in 38 fractions planned between March 2009 and 2012. The results were used to determine if the tolerance limits currently being used for IMRT QA were able to indicate if the process was under control. The SPC calculations were repeated for IMRT QA of the same type of cases that were planned after the treatment planning system was upgraded from Eclipse version 8.1.18 to version 10.0.39. The initial tolerance limits were found to be acceptable for two of the three metrics tested prior to the upgrade. After the upgrade to the treatment planning system the SPC analysis found that the a priori limits were no longer capable of indicating control for 2 of the 3 metrics analyzed. The changes in the IMRT QA results were clearly identified using SPC, indicating that it is a useful tool for finding changes in the IMRT QA process. Routine application of SPC to IMRT QA results would help to distinguish unintentional trends and changes from the random variation in the IMRT QA results for individual plans. © 2012 American Association of Physicists in Medicine.

Methods for computational disease surveillance in infection prevention and control: Statistical process control versus Twitter's anomaly and breakout detection algorithms.

PubMed

Wiemken, Timothy L; Furmanek, Stephen P; Mattingly, William A; Wright, Marc-Oliver; Persaud, Annuradha K; Guinn, Brian E; Carrico, Ruth M; Arnold, Forest W; Ramirez, Julio A

2018-02-01

Although not all health care-associated infections (HAIs) are preventable, reducing HAIs through targeted intervention is key to a successful infection prevention program. To identify areas in need of targeted intervention, robust statistical methods must be used when analyzing surveillance data. The objective of this study was to compare and contrast statistical process control (SPC) charts with Twitter's anomaly and breakout detection algorithms. SPC and anomaly/breakout detection (ABD) charts were created for vancomycin-resistant Enterococcus, Acinetobacter baumannii, catheter-associated urinary tract infection, and central line-associated bloodstream infection data. Both SPC and ABD charts detected similar data points as anomalous/out of control on most charts. The vancomycin-resistant Enterococcus ABD chart detected an extra anomalous point that appeared to be higher than the same time period in prior years. Using a small subset of the central line-associated bloodstream infection data, the ABD chart was able to detect anomalies where the SPC chart was not. SPC charts and ABD charts both performed well, although ABD charts appeared to work better in the context of seasonal variation and autocorrelation. Because they account for common statistical issues in HAI data, ABD charts may be useful for practitioners for analysis of HAI surveillance data. Copyright © 2018 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

Single cell digital polymerase chain reaction on self-priming compartmentalization chip.

PubMed

Zhu, Qiangyuan; Qiu, Lin; Xu, Yanan; Li, Guang; Mu, Ying

2017-01-01

Single cell analysis provides a new framework for understanding biology and disease, however, an absolute quantification of single cell gene expression still faces many challenges. Microfluidic digital polymerase chain reaction (PCR) provides a unique method to absolutely quantify the single cell gene expression, but only limited devices are developed to analyze a single cell with detection variation. This paper describes a self-priming compartmentalization (SPC) microfluidic digital polymerase chain reaction chip being capable of performing single molecule amplification from single cell. The chip can be used to detect four single cells simultaneously with 85% of sample digitization. With the optimized protocol for the SPC chip, we first tested the ability, precision, and sensitivity of our SPC digital PCR chip by assessing β-actin DNA gene expression in 1, 10, 100, and 1000 cells. And the reproducibility of the SPC chip is evaluated by testing 18S rRNA of single cells with 1.6%-4.6% of coefficient of variation. At last, by detecting the lung cancer related genes, PLAU gene expression of A549 cells at the single cell level, the single cell heterogeneity was demonstrated. So, with the power-free, valve-free SPC chip, the gene copy number of single cells can be quantified absolutely with higher sensitivity, reduced labor time, and reagent. We expect that this chip will enable new studies for biology and disease.

Enhancement effects of chelating agents on the degradation of tetrachloroethene in Fe(III) catalyzed percarbonate system

PubMed Central

Miao, Zhouwei; Gu, Xiaogang; Lu, Shuguang; Brusseau, Mark L.; Zhang, Xiang; Fu, Xiaori; Danish, Muhammad; Qiu, Zhaofu; Sui, Qian

2015-01-01

The performance of Fe(III)-based catalyzed sodium percarbonate (SPC) for stimulating the oxidation of tetrachloroethene (PCE) for groundwater remediation applications was investigated. The chelating agents citric acid monohydrate (CIT), oxalic acid (OA), and Glutamic acid (Glu) significantly enhanced the degradation of PCE. Conversely, ethylenediaminetetraacetic acid (EDTA) had a negative impact on PCE degradation, which may due to its strong Fe chelation and HO• scavenging abilities. However, excessive SPC or chelating agent will retard PCE degradation. In addition, investigations using free radical probe compounds and radical scavengers revealed that PCE was primarily degraded by HO• radical oxidation in both the chelated and non-chelated systems, while O2•− also participated in the non-chelated system and the OA and Glu modified systems. According to the electron paramagnetic resonance (EPR) studies, the presence of HO• in the Fe(III)/SPC system was maintained much longer than that in the Fe(II)/SPC system. The results indicated that the addition of CIT, OA or Glu indeed enhanced the generation of HO• in the first 10 min and promoted degradation efficiency by increasing the amount of Fe(III) and maintaining the concentration of HO• radicals in solution. In conclusion, chelated Fe(III)-based catalyzed SPC oxidation is a promising method for the remediation of PCE-contaminated groundwater. PMID:26549979

Squalene-containing nanostructured lipid carriers promote percutaneous absorption and hair follicle targeting of diphencyprone for treating alopecia areata.

PubMed

Lin, Yin-Ku; Al-Suwayeh, Saleh A; Leu, Yann-Lii; Shen, Feng-Ming; Fang, Jia-You

2013-02-01

Diphencyprone (DPCP) is a therapeutic agent for treating alopecia areata. To improve skin absorption and follicular targeting nanostructured lipid carriers (NLCs) were developed. Nanoparticles were characterized by size, zeta potential, molecular environment, differential scanning calorimetry (DSC), and nuclear magnetic resonance (NMR). In vitro and in vivo skin absorption experiments were performed. Fluorescence and confocal microscopes for imaging skin distribution were used. NLCs with different designs were 208 ~ 265 nm with  > 77% DPCP encapsulation. NLCs incorporating a cationic surfactant or more soybean phosphatidylcholine (SPC) showed higher lipophilicity compared to typical NLCs by Nile red emission. All NLCs tested revealed controlled DPCP release; burst release was observed for control. The formulation with more SPC provided 275 μg/g DPCP skin retention, which was greater than control and other NLCs. Intersubject deviation was reduced after DPCP loading into NLCs. Cyanoacrylate skin biopsy demonstrated greater follicular deposition for NLCs with more SPC compared to control. Cationic NLCs but not typical or SPC-containing carriers were largely internalized into keratinocytes. In vivo skin retention of NLCs with more SPC was higher than free control. Confocal imaging confirmed localization of NLCs in follicles and intercellular lipids of stratum corneum. This work encourages further investigation of DPCP absorption using NLCs with a specific formulation design.

Unique secreted–surface protein complex of Lactobacillus rhamnosus, identified by phage display

PubMed Central

Gagic, Dragana; Wen, Wesley; Collett, Michael A; Rakonjac, Jasna

2013-01-01

Proteins are the most diverse structures on bacterial surfaces; hence, they are candidates for species- and strain-specific interactions of bacteria with the host, environment, and other microorganisms. Genomics has decoded thousands of bacterial surface and secreted proteins, yet the function of most cannot be predicted because of the enormous variability and a lack of experimental data that would allow deduction of function through homology. Here, we used phage display to identify a pair of interacting extracellular proteins in the probiotic bacterium Lactobacillus rhamnosus HN001. A secreted protein, SpcA, containing two bacterial immunoglobulin-like domains type 3 (Big-3) and a domain distantly related to plant pathogen response domain 1 (PR-1-like) was identified by screening of an L. rhamnosus HN001 library using HN001 cells as bait. The SpcA-“docking” protein, SpcB, was in turn detected by another phage display library screening, using purified SpcA as bait. SpcB is a 3275-residue cell-surface protein that contains general features of large glycosylated Serine-rich adhesins/fibrils from gram-positive bacteria, including the hallmark signal sequence motif KxYKxGKxW. Both proteins are encoded by genes within a L. rhamnosus-unique gene cluster that distinguishes this species from other lactobacilli. To our knowledge, this is the first example of a secreted-docking protein pair identified in lactobacilli. PMID:23233310

Statistical Process Control in the Practice of Program Evaluation.

ERIC Educational Resources Information Center

Posavac, Emil J.

1995-01-01

A technique developed to monitor the quality of manufactured products, statistical process control (SPC), incorporates several features that may prove attractive to evaluators. This paper reviews the history of SPC, suggests how the approach can enrich program evaluation, and illustrates its use in a hospital-based example. (SLD)

Applied Behavior Analysis and Statistical Process Control?

ERIC Educational Resources Information Center

Hopkins, B. L.

1995-01-01

Incorporating statistical process control (SPC) methods into applied behavior analysis is discussed. It is claimed that SPC methods would likely reduce applied behavior analysts' intimate contacts with problems and would likely yield poor treatment and research decisions. Cases and data presented by Pfadt and Wheeler (1995) are cited as examples.…

Using Statistical Process Control to Make Data-Based Clinical Decisions.

ERIC Educational Resources Information Center

Pfadt, Al; Wheeler, Donald J.

1995-01-01

Statistical process control (SPC), which employs simple statistical tools and problem-solving techniques such as histograms, control charts, flow charts, and Pareto charts to implement continual product improvement procedures, can be incorporated into human service organizations. Examples illustrate use of SPC procedures to analyze behavioral data…

Virtual Human Analogs to Rodent Spatial Pattern Separation and Completion Memory Tasks

ERIC Educational Resources Information Center

Paleja, Meera; Girard, Todd A.; Christensen, Bruce K.

2011-01-01

Spatial pattern separation (SPS) and spatial pattern completion (SPC) have played an increasingly important role in computational and rodent literatures as processes underlying associative memory. SPS and SPC are complementary processes, allowing the formation of unique representations and the reconstruction of complete spatial environments based…

Neuroprotective effect of S-allyl-l-cysteine derivatives against endoplasmic reticulum stress-induced cytotoxicity is independent of calpain inhibition.

PubMed

Imai, Toru; Kosuge, Yasuhiro; Saito, Hiroaki; Uchiyama, Taketo; Wada, Taira; Shimba, Shigeki; Ishige, Kumiko; Miyairi, Shinichi; Makishima, Makoto; Ito, Yoshihisa

2016-03-01

S-allyl-l-cysteine (SAC) is known to have neuroprotective properties. We synthesized various SAC derivatives and tested their effects on endoplasmic reticulum stress-induced neurotoxicity in cultured hippocampal neurons (HPNs). Among the compounds tested, S-propyl-l-cysteine (SPC) exhibited the strongest neuroprotective activity in HPNs, followed by S-ethyl-l-cysteine (SEC) and S-methyl-l-cysteine (SMC). Unlike SAC and SMC, SPC and SEC did not have inhibitory activity on μ-calpain, suggesting that the mechanism underlying the protective activity of SPC and SEC differs from that of SAC. Copyright © 2016 Japanese Pharmacological Society. Production and hosting by Elsevier B.V. All rights reserved.

Quality Space and Launch Requirements, Addendum to AS9100C

DTIC Science & Technology

2015-05-08

45 8.9.1 Statistical Process Control (SPC) .......................................................................... 45...SMC Space and Missile Systems Center SME Subject Matter Expert SOW Statement of Work SPC Statistical Process Control SPO System Program Office SRP...occur without any individual data exceeding the control limits. Control limits are developed using standard statistical methods or other approved

Applying Statistical Process Quality Control Methodology to Educational Settings.

ERIC Educational Resources Information Center

Blumberg, Carol Joyce

A subset of Statistical Process Control (SPC) methodology known as Control Charting is introduced. SPC methodology is a collection of graphical and inferential statistics techniques used to study the progress of phenomena over time. The types of control charts covered are the null X (mean), R (Range), X (individual observations), MR (moving…

Training Factory Workers: Three Case Studies. Contractor Report.

ERIC Educational Resources Information Center

Hirschhorn, Larry D.

Case studies examined the context and impact of training in three factories: a bakery, a circuit assembly plant, and a plant that produces microchips. Cookie-Foods, Inc. used Statistical Process Control (SPC) and a course on problem solving to increase the operators' productivity. Impact of the SPC program was limited, because workers who…

The World in Their Laps.

ERIC Educational Resources Information Center

Duncan, Lucy E.

2003-01-01

Discusses the St. Philip's College (SPC) Learning Resource Center laptop loaning program. States that SPC is a Historically Black College and Hispanic Serving Institution that is now rewarding honors students by lending them laptops for a semester at a time. Discusses the development of the loaning program. Provides a list of Web sites for anyone…

Adolescents' Perceived Control in the Sociopolitical Domain: A Latent Class Analysis

ERIC Educational Resources Information Center

Christens, Brian D.; Peterson, N. Andrew; Reid, Robert J.; Garcia-Reid, Pauline

2015-01-01

Sociopolitical control (SPC) has been identified as a critical component of empowerment, resilience and civic development among young people. Sociopolitical control has been assessed according to a two dimensional model: (1) leadership competence and (2) policy control. Very little is known, however, about heterogeneity of perceptions of SPC, how…

WFIRST Coronagraph Technology Development Testbeds: Status and Recent Testbed Results

NASA Astrophysics Data System (ADS)

Shi, Fang; An, Xin; Balasubramanian, Kunjithapatham; cady, eric; Gordon, Brian; Greer, Frank; Kasdin, N. Jeremy; Kern, Brian; Lam, Raymond; Marx, David; Moody, Dwight; Patterson, Keith; Poberezhskiy, Ilya; mejia prada, camilo; Gersh-Range, Jessica; Eldorado Riggs, A. J.; Seo, Byoung-Joon; Shields, Joel; Sidick, Erkin; Tang, Hong; Trauger, John Terry; Truong, Tuan; White, Victor; Wilson, Daniel; Zhou, Hanying; JPL WFIRST Testbed Team, Princeton University

2018-01-01

As a part of technology development for the WFIRST coronagraph instrument (CGI), dedicated testbeds are built and commissioned at JPL. The coronagraph technology development testbeds include the Occulting Mask Coronagraph (OMC) testbed, the Shaped Pupil Coronagraph/Integral Field Spectrograph (SPC/IFS) testbed, and the Vacuum Surface Gauge (VSG) testbed. With its configuration similar to the WFIRST flight coronagraph instrument the OMC testbed consists of two coronagraph modes, Shaped Pupil Coronagraph (SPC) and Hybrid Lyot Coronagraph (HLC), a low order wavefront sensor (LOWFS), and an optical telescope assembly (OTA) simulator which can generate realistic LoS drift and jitter as well as low order wavefront error that would be induced by the WFIRST telescope’s vibration and thermal changes. The SPC/IFS testbed is a dedicated testbed to test the IFS working with a Shaped Pupil Coronagraph while the VSG testbed is for measuring and calibrating the deformable mirrors, a key component used for WFIRST CGI's wavefront control. In this poster, we will describe the testbed functions and status as well as the highlight of the latest testbed results from OMC, SPC/IFS and VSG testbeds.

Field study of pneumonia in vaccinated cattle associated with incorrect vaccination and Pasteurella multocida infection.

PubMed

Crawshaw, W M; Caldow, G L

2015-04-25

This field study used data on the vaccine courses against bovine respiratory disease sold by one pharmaceutical company in conjunction with pharmacovigilance data to explore reported suspected lack of expected efficacy and the reasons for this. The study ran from May 1, 2007, to April 30, 2010, and covered vaccines sold in Scotland and part of Northumberland. In total, 83 groups of cattle reported suspected lack of expected efficacy, representing 1.6 per cent of the 804,618 vaccine courses sold. It was possible to investigate 45 of these outbreaks in depth using a standard questionnaire and diagnostic protocol. Vaccine usage outwith the specific product characteristics (SPC) occurred in 47 per cent of cases (21/45). The proportion of vaccination courses used where a pathogen contained in the vaccine was detected in the diseased cattle and vaccine use was consistent with the SPC was estimated at 0.12 per cent of the courses sold. Pasteurella multocida was the most common pathogen detected and was found in 21 of the outbreaks. For outbreaks where a pathogen contained in the vaccine was detected, P. multocida was found at a significantly greater frequency (P=0.03) where vaccine use was compliant with the SPC (five of six outbreaks) compared with outbreaks where vaccine use had not been compliant with the SPC (one of seven outbreaks). The limitations of the study, including the diagnostic tests employed and definition of vaccination outwith the SPC, are discussed. British Veterinary Association.

Synthesis, crystal structure, and biological evaluation of a series of phloretin derivatives.

PubMed

Wang, Li; Li, Zheng-Wei; Zhang, Wei; Xu, Rui; Gao, Fei; Liu, Yang-Feng; Li, Ya-Jun

2014-10-13

A one-step synthesis of phloretin derivatives 2-11 from phloretin in good to excellent yields is reported. Their structures were characterized by 1H-NMR, 13C-NMR and MS, and the structures of 8 and 11 were determined by X-ray diffraction analysis. A mechanism for the formation of 9-11 is proposed. Compared with the anticancer drug docetaxel, phloretin, phloretin derivatives and phlorizin exhibited moderate cytotoxicity toward the MDA-MB-231, SPC-A1, A549, MCF-7 and EC109 cell lines. Among all of the tested compounds, 7 exhibited the strongest cytotoxicity toward the five cell lines and was more active than docetaxel in MDA-MB-231 cells. Our findings suggest that these derivatives hold great promise for further development as anticancer agents.

Determinants of pupil diameters and pupil dynamics in an adult Chinese population.

PubMed

Zheng, Ce; de Leon, John Mark S; Cheung, Carol Y; Narayanaswamy, Arun K; Ong, Sim-Heng; Tan, Clement W; Chew, Paul T; Perera, Shamira A; Wong, Tien Y; Aung, Tin

2016-05-01

To investigate the determinants of pupil diameter (PD), amplitude of pupil diameter change (PD-change) and speed of pupil constriction (SPC) using video anterior segment optical coherence tomography (AS-OCT) in a population-based sample of Chinese adults. Chinese adults aged 40 to 80 years who were free from glaucoma were consecutively recruited from the population-based Singapore Chinese Eye Study. The SPC was measured by AS-OCT videography. Univariate and multivariate analyses were performed to examine the effects of demographic and ocular biometric factors (e.g., axial length [AL], anterior chamber depth [ACD], baseline PD, iris thickness at the area of the dilator muscle [ITDMR], iris area [IA], and iris bowing [IB]) on SPC, PD, and PD-change. A total of 266/302 (89.5 %) AS-OCT videos of eligible eyes were available for analysis. Among these subjects, 64.3 % were women, and the mean age (± standard deviation [SD]) was 56 ± 8.3 years. SPC was not associated with sex. In multiple regression analyses, SPC was independently associated with baseline PD (β = 0.116, p = 0.006). Baseline PD was independently associated with ACD (β = 0.341, p < 0.001), TISA 500 (β = -4.513, p < 0.001), IA (β = -2.796, p < 0.001), and ITDMR (β = 6.573, p < 0.001). PD-change was independently associated with ACD (β = 0.256, p < 0.001), IA (β = -1.507, p < 0.001), IB (β = 0.630, p = 0.011), and ITDMR (β = 3.124, p < 0.001). Among normal eyes in an adult Chinese population, SPC was associated with larger baseline PD. Larger baseline PD and greater PD change form dark to light were associated with greater ACD, with smaller IA and thicker ITDMR.

Enumeration of the contaminating bacterial microbiota in unfermented pasteurized milks enriched with probiotic bacteria.

PubMed

Champagne, C P; Raymond, Y; Gonthier, J; Audet, P

2009-04-01

Pasteurized and unfermented milks supplemented with probiotic bacteria are appearing on the market. It then becomes a challenge to ascertain the undesirable contamination microbiota in the presence of a largely superior population of probiotic bacteria. A method to enumerate the contaminating microbial microbiota in such probiotic-enriched milks was developed. The probiotic cultures, Lactobacillus rhamnosus Lb-Immuni-T and Bifidobacterium animalis subsp. lactis BB-12(R), were added to a pasteurized unfermented milk to reach a minimum of 1 billion CFU per 250 mL portion, as ascertained by plating on de Man - Rogosa - Sharpe (MRS) agar in anaerobic conditions. No growth of B. animalis subsp. lactis BB-12 was noted on plate count agar (PCA) or Petrifilm plates, and the presence of this culture did not affect standard plate counts (SPC) of contaminating bacteria. However, L. rhamnosus formed colonies on PCA and Petrifilm plates. Attempts were thus made to inhibit the growth of the probiotic lactobacilli in PCA. The addition of 2% sodium phosphate (SP) or 5% glycerophosphate (GP) inhibited the growth of the lactobacilli in broths, but pin-point colonies of L. rhamnosus Lb-Immuni-T nevertheless appeared on PCA supplemented with phosphates. SPC could be obtained on PCA + 2% SP by only counting the large colonies, but this resulted in a significant (4.4 fold) underestimation of SPC values. On Petrifilm AC, at dilutions 0 to 2, all colonies were considered as being contaminants, while at dilutions 3 and 4, only large colonies were counted for SPC determinations. There was a direct correlation (R2 = 0.99) between SPC values with Petrifilm in uninoculated milks and those obtained on probiotic-enriched milks. The high correlation obtained over the 102 to 106 CFU/mL range of SPC values show that this Petrifilm method is appropriate to evaluate the microbiological quality of pasteurized milks enriched with L. rhamnosus Lb-Immuni-T and B. animalis subsp. lactis BB-12.

Sphaerochaeta multiformis sp. nov., an anaerobic, psychrophilic bacterium isolated from subseafloor sediment, and emended description of the genus Sphaerochaeta.

PubMed

Miyazaki, Masayuki; Sakai, Sanae; Ritalahti, Kirsti M; Saito, Yayoi; Yamanaka, Yuko; Saito, Yumi; Tame, Akihiko; Uematsu, Katsuyuki; Löffler, Frank E; Takai, Ken; Imachi, Hiroyuki

2014-12-01

An anaerobic, psychrophilic bacterium, strain MO-SPC2(T), was isolated from a methanogenic microbial community in a continuous-flow bioreactor that was established from subseafloor sediments collected from off the Shimokita Peninsula of Japan in the north-western Pacific Ocean. Cells were pleomorphic: spherical, annular, curved rod, helical and coccoid cell morphologies were observed. Motility only occurred in helical cells. Strain MO-SPC2(T) grew at 0-17 °C (optimally at 9 °C), at pH 6.0-8.0 (optimally at pH 6.8-7.2) and in 20-40 g NaCl l(-1) (optimally at 20-30 NaCl l(-1)). The strain grew chemo-organotrophically with mono-, di- and polysaccharides. The major end products of glucose fermentation were acetate, ethanol, hydrogen and carbon dioxide. The abundant polar lipids of strain MO-SPC2(T) were phosphatidylglycolipids, phospholipids and glycolipids. The major cellular fatty acids were C14 : 0, C16 : 0 and C16 : 1ω9. Isoprenoid quinones were not detected. The G+C content of the DNA was 32.3 mol%. 16S rRNA gene-based phylogenetic analysis showed that strain MO-SPC2(T) was affiliated with the genus Sphaerochaeta within the phylum Spirochaetes, and its closest relatives were Sphaerochaeta pleomorpha Grapes(T) (88.4 % sequence identity), Sphaerochaeta globosa Buddy(T) (86.7 %) and Sphaerochaeta coccoides SPN1(T) (85.4 %). Based on phenotypic characteristics and phylogenetic traits, strain MO-SPC2(T) is considered to represent a novel species of the genus Sphaerochaeta, for which the name Sphaerochaeta multiformis sp. nov. is proposed. The type strain is MO-SPC2(T) ( = JCM 17281(T) = DSM 23952(T)). An emended description of the genus Sphaerochaeta is also proposed. © 2014 IUMS.

Coupling of solar photoelectro-Fenton with a BDD anode and solar heterogeneous photocatalysis for the mineralization of the herbicide atrazine.

PubMed

Garza-Campos, Benjamín R; Guzmán-Mar, Jorge Luis; Reyes, Laura Hinojosa; Brillas, Enric; Hernández-Ramírez, Aracely; Ruiz-Ruiz, Edgar J

2014-02-01

Here, the synergetic effect of coupling solar photoelectro-Fenton (SPEF) and solar heterogeneous photocatalysis (SPC) on the mineralization of 200mL of a 20mg L(-1) atrazine solution, prepared from the commercial herbicide Gesaprim, at pH 3.0 was studied. Uniform, homogeneous and adherent anatase-TiO2 films onto glass spheres of 5mm diameter were prepared by the sol-gel dip-coating method and used as catalyst for SPC. However, this procedure yielded a poor removal of the substrate because of the low oxidation ability of positive holes and OH formed at the catalyst surface to destroy it. Atrazine decay was improved using anodic oxidation (AO), electro-Fenton (EF), SPEF and coupled SPEF-SPC at 100mA. The electrolytic cell contained a boron-doped diamond (BDD) anode and H2O2 was generated at a BDD cathode fed with an air flow. The removal and mineralization of atrazine increased when more oxidizing agents were generated in the sequence AO

Male Breast Cancer as a Second Primary Cancer: Increased Risk Following Lymphoma.

PubMed

Farr, Deborah E; Thomas, Alexandra; Khan, Seema Ahsan; Schroeder, Mary C

2017-08-01

Male breast cancer (MBC) as a second primary cancer (SPC) has a known association with prior MBC. However, its association with non-breast index malignancies, relative to population risk, has not been previously reported. Using Surveillance, Epidemiology, and End Results program (9 catchment area) data, we identified MBCs diagnosed from 1973-2012 as their SPC. Information regarding the index malignancy was also obtained. Standardized incidence ratios (SIR) of MBC as SPC were estimated, along with incidence rates and trends. Kaplan-Meier curves were used to estimate survival. Over a 38-year period, 464 MBCs were identified as SPC. The most common index malignancies were breast (SIR 30.86, 95% confidence interval [CI] 21.50-42.92, p  < .001), lymphoma (SIR 1.58, 95% CI 1.08-2.22, p  = .014), melanoma (SIR 1.26, 95% CI 0.80-1.89), urinary (SIR 1.05, 95% CI 0.74-1.43), colorectal (SIR 0.94, 95% CI 0.69-1.24), and prostate (SIR 0.93 95% CI 0.81-1.07). Apart from the known association with prior breast cancer, the only significant association was with lymphoma as an index cancer, although not significant with a Bonferroni correction. From 1975-2012, incidence of breast cancer as a first cancer increased at an annual percentage change of 1.3% while breast cancer as a SPC increased at 4.7% (both p values < .001). Male breast cancer as a SPC has increased markedly over 4 decades. Men with a history of lymphoma may experience higher-than-expected rates of breast SPC. These observations warrant further research, and suggest possible etiologic connections with disease biology, prior therapy, or genetics. This study reports that men are presenting more frequently to the clinic with breast cancer, both as an initial cancer and as a second cancer following an earlier malignancy. We also report the novel observation that men who survive lymphoma are at increased risk of developing a subsequent breast cancer. Further work is needed to better understand possible treatment or biologic causes of this association. More immediately, these findings suggest the need for heightened vigilance for male breast cancer overall and, in particular, for male lymphoma survivors. © AlphaMed Press 2017.

Effect of montmorillonite clay addition on the morphological and physical properties of Jatropha curcas L. and Glycine max L. protein concentrate films

USDA-ARS?s Scientific Manuscript database

Protein concentrates from jatropha (JPC) and soy seeds (SPC) were obtained by solubilization and acid precipitation of proteins. Films from JPC and SPC were prepared by the casting method, using two different montmorillonite (MMT) clay concentrations and plasticized with glycerol. Film properties we...

Fieldcrest Cannon, Inc. Advanced Technical Preparation. Statistical Process Control (SPC). PRE-SPC I. Instructor Book.

ERIC Educational Resources Information Center

Averitt, Sallie D.

This instructor guide, which was developed for use in a manufacturing firm's advanced technical preparation program, contains the materials required to present a learning module that is designed to prepare trainees for the program's statistical process control module by improving their basic math skills and instructing them in basic calculator…

Statistical Process Control. Impact and Opportunities for Ohio.

ERIC Educational Resources Information Center

Brown, Harold H.

The first purpose of this study is to help the reader become aware of the evolution of Statistical Process Control (SPC) as it is being implemented and used in industry today. This is approached through the presentation of a brief historical account of SPC, from its inception through the technological miracle that has occurred in Japan. The…

Disciplined Decision Making in an Interdisciplinary Environment: Some Implications for Clinical Applications of Statistical Process Control.

ERIC Educational Resources Information Center

Hantula, Donald A.

1995-01-01

Clinical applications of statistical process control (SPC) in human service organizations are considered. SPC is seen as providing a standard set of criteria that serves as a common interface for data-based decision making, which may bring decision making under the control of established contingencies rather than the immediate contingencies of…

Identifying Hail Signatures in Satellite Imagery from the 9-10 August 2011 Severe Weather Event

NASA Technical Reports Server (NTRS)

Dryden, Rachel L.; Molthan, Andrew L.; Cole, Tony A.; Bell, Jordan R.

2014-01-01

Hail scars are identifiable in MODIS satellite imagery based on NDVI change, which was dominantly negative. Hail damage spatially correlates with SPC hail reports and MESH. This study developed a proxy for quantifying crop loss at varying thresholds to address the gap between SPC damage estimates and insurance payouts.

Statistical process control in nursing research.

PubMed

Polit, Denise F; Chaboyer, Wendy

2012-02-01

In intervention studies in which randomization to groups is not possible, researchers typically use quasi-experimental designs. Time series designs are strong quasi-experimental designs but are seldom used, perhaps because of technical and analytic hurdles. Statistical process control (SPC) is an alternative analytic approach to testing hypotheses about intervention effects using data collected over time. SPC, like traditional statistical methods, is a tool for understanding variation and involves the construction of control charts that distinguish between normal, random fluctuations (common cause variation), and statistically significant special cause variation that can result from an innovation. The purpose of this article is to provide an overview of SPC and to illustrate its use in a study of a nursing practice improvement intervention. Copyright © 2011 Wiley Periodicals, Inc.

Liquid Crystals in Chromatography

NASA Astrophysics Data System (ADS)

Witkiewicz, Zygfryd

The following sections are included: * INTRODUCTION * LIQUID CRYSTALS SUITABLE FOR GAS CHROMATOGRAPHY * Monomeric Liquid Crystal Stationary Phases * Polymeric Liquid Crystal Stationary Phases * Polymeric Liquid Crystal Stationary Phases * Conventional Analytical Columns * Capillary Columns * FACTORS AFFECTING THE CHROMATOGRAPHIC SEPARATIONS ON LIQUID CRYSTAL STATIONARY PHASES * Kind of Mesophase of the Liquid Crystal * Molecular Structure of the Liquid Crystals and of the Chromatographed Substances * Substrate on which the Liquid Crystal is Deposited * ANALYTICAL APPLICATIONS OF LIQUID CRYSTAL STATIONARY PHASES IN GAS CHROMATOGRAPHY * Separation of Isomers of Benzene and Naphthalene Derivatives * Separation of Alkane and Alkene Isomers * Separation of Mixtures of Benzene and Aliphatic Hydrocarbon Derivatives Containing Heteroatoms * Separation of Polynuclear Hydrocarbons * INVESTIGATION OF THE PROPERTIES OF LIQUID CRYSTALS BY GAS CHROMATOGRAPHY * APPLICATION OF LIQUID CRYSTALS IN LIQUID CHROMATOGRAPHY * Column Chromatography * Thin-Layer Chromatography * APPLICATION OF LIQUID CRYSTAL STATIONARY PHASES IN SUPERCRITICAL FLUID CHROMATOGRAPHY * FINAL REMARKS * References

“The 3/3 Strategy”: A Successful Multifaceted Hospital Wide Hand Hygiene Intervention Based on WHO and Continuous Quality Improvement Methodology

PubMed Central

Mestre, Gabriel; Berbel, Cristina; Tortajada, Purificación; Alarcia, Margarita; Coca, Roser; Gallemi, Gema; Garcia, Irene; Fernández, Mari Mar; Aguilar, Mari Carmen; Martínez, José Antonio; Rodríguez-Baño, Jesús

2012-01-01

Background Only multifaceted hospital wide interventions have been successful in achieving sustained improvements in hand hygiene (HH) compliance. Methodology/Principal Findings Pre-post intervention study of HH performance at baseline (October 2007– December 2009) and during intervention, which included two phases. Phase 1 (2010) included multimodal WHO approach. Phase 2 (2011) added Continuous Quality Improvement (CQI) tools and was based on: a) Increase of alcohol hand rub (AHR) solution placement (from 0.57 dispensers/bed to 1.56); b) Increase in frequency of audits (three days every three weeks: “3/3 strategy”); c) Implementation of a standardized register form of HH corrective actions; d) Statistical Process Control (SPC) as time series analysis methodology through appropriate control charts. During the intervention period we performed 819 scheduled direct observation audits which provided data from 11,714 HH opportunities. The most remarkable findings were: a) significant improvements in HH compliance with respect to baseline (25% mean increase); b) sustained high level (82%) of HH compliance during intervention; c) significant increase in AHRs consumption over time; c) significant decrease in the rate of healthcare-acquired MRSA; d) small but significant improvements in HH compliance when comparing phase 2 to phase 1 [79.5% (95% CI: 78.2–80.7) vs 84.6% (95% CI:83.8–85.4), p<0.05]; e) successful use of control charts to identify significant negative and positive deviations (special causes) related to the HH compliance process over time (“positive”: 90.1% as highest HH compliance coinciding with the “World hygiene day”; and “negative”:73.7% as lowest HH compliance coinciding with a statutory lay-off proceeding). Conclusions/Significance CQI tools may be a key addition to WHO strategy to maintain a good HH performance over time. In addition, SPC has shown to be a powerful methodology to detect special causes in HH performance (positive and negative) and to help establishing adequate feedback to healthcare workers. PMID:23110061

Effectiveness of risk minimization measures for cabergoline-induced cardiac valve fibrosis in clinical practice in Italy.

PubMed

Italiano, Domenico; Bianchini, Elisa; Ilardi, Maura; Cilia, Roberto; Pezzoli, Gianni; Zanettini, Renzo; Vacca, Laura; Stocchi, Fabrizio; Bramanti, Placido; Ciurleo, Rosella; Di Lorenzo, Giuseppe; Polimeni, Giovanni; de Luise, Cynthia; Ross, Douglas; Rijnbeek, Peter; Sturkenboom, Miriam; Trifirò, Gianluca

2015-06-01

On June 2008, the European Medicines Agency (EMA) introduced changes to the Summary of Product Characteristics (SPC) for cabergoline and pergolide, to reduce the risk of cardiac valvulopathy in users of these drugs. To assess the effectiveness of EMA recommendations in Italian clinical practice, we retrospectively reviewed medical charts of patients with degenerative Parkinsonism treated with cabergoline in three large Italian clinics between January 2006 and June 2012. The prevalence and the severity of cardiac valve regurgitation were assessed in patients who stopped cabergoline therapy prior to June 2008 or continued therapy after that date. In addition, the proportion of patients undergoing echocardiographic examination in each cohort was evaluated. A total of 61 patients were available for evaluation. The proportion of patients who underwent a baseline echocardiographic examination increased from 64 % in the period before the 2008 SPC changes to 71 % among those who continued treatment after that date. However, only 18 and 29 % of patients underwent at least two echocardiographic examinations during the pre-SPC and cross-SPC change period, respectively. No severe cardiac valve regurgitation was documented in any of the study patients using cabergoline either prior or after 26th June 2008. Our findings show that the 2008 changes to the SPC resulted in an increase in physicians' awareness of cabergoline-induced valvulopathy risk in Italy. However, only a small percentage of patients underwent serial echocardiography. Further efforts are needed to achieve better compliance with the prescribing guidelines for cabergoline treated patients in clinical practice.

Variability in the quality of overdose advice in Summary of Product Characteristics (SPC) documents: gut decontamination recommendations for CNS drugs.

PubMed

Wall, Andrew J B; Bateman, D N; Waring, W S

2009-01-01

Deliberate self-poisoning is a major cause of morbidity and mortality. The Summary of Product Characteristics (SPC) document is a legal requirement for all drugs, and Section 4.9 addresses the features of toxicity and clinical advice on management of overdose. The quality and appropriateness of this advice have received comparatively little attention. Section 4.9 of the SPC was examined for all drugs in the central nervous system (CNS) category of the British National Formulary. Advice concerning gut decontamination was examined with respect to specific interventions: induced vomiting, oral activated charcoal, gastric lavage, and other interventions. Data were compared with standard reference sources for clinical management advice in poisoning. These were graded 'A' if no important differences existed, 'B' if differences were noted but not thought clinically important, and 'C' if differences were thought to be clinically significant. SPC documents were examined for 258 medications from 67 manufacturers. The overall agreement was 'A' in 23 (8.9%), 'B' in 28 (10.9%) and 'C' in 207 (80.2%). Discrepancies were due to inappropriate recommendation of induced emesis in 21.7% (95% confidence interval 17.1, 27.1), gastric lavage in 38.4% (32.7, 44.4), other gut decontamination in 5.8% (3.6, 9.4) and failure to recommend oral activated charcoal in 57.4% (51.1, 63.4). Gut decontamination advice in SPC documents with respect to CNS drugs was inadequate. Possible reasons for the observed discrepancies and ways of improving the consistency of advice are proposed.

Results of Surgery for Low-Grade Brain Arteriovenous Malformation Resection by Early Career Neurosurgeons: An Observational Study.

PubMed

Patel, Nirav J; Bervini, David; Eftekhar, Behzad; Davidson, Andrew Stewart; Walsh, Daniel C; Assaad, Nazih N; Morgan, Michael Kerin

2018-03-28

For sustainability of arteriovenous malformation (AVM) surgery, results from early career cerebrovascular neurosurgeons (ECCNs) must be acceptably safe. To determine whether ECCNs performance of Spetzler-Ponce Class A AVM (SPC A) resection can be acceptably safe. ECCNs completing a cerebrovascular fellowship (2004-2015) with the last author were included. Inclusion of the ECCN cases occurred if they: had a prospective database of all AVM cases since commencing independent practice; were the primary surgeon on SPC A; and had made the significant management decisions. All SPC A surgical cases from the beginning of the ECCN's independent surgical practice to a maximum of 8 yr were included. An adverse outcome was considered a complication of surgery leading to a new permanent neurological deficit with a last modified Rankin Scale score >1. A cumulative summation (Cusum) plot examined the performance of each surgery. The highest acceptable level of adverse outcomes for the Cusum was 3.3%, derived from the upper 95% confidence interval of the last author's reported series. Six ECCNs contributed 110 cases for analysis. The median number of SPC A cases operated by each ECCN was 16.5 (range 4-40). Preoperative embolization was performed in 5 (4.5%). The incidence of adverse outcomes was 1.8% (95% confidence interval: <0.01%-6.8%). At no point during the accumulated series did the combined cohort become unacceptable by the Cusum plot. ECCNs with appropriate training appointed to large-volume cerebrovascular centers can achieve results for surgery for SPC A that are not appreciably worse than those published from high-volume neurosurgeons.

Preparative crystallization of a single chain antibody using an aqueous two-phase system.

PubMed

Huettmann, Hauke; Berkemeyer, Matthias; Buchinger, Wolfgang; Jungbauer, Alois

2014-11-01

A simultaneous crystallization and aqueous two-phase extraction of a single chain antibody was developed, demonstrating process integration. The process conditions were designed to form an aqueous two-phase system, and to favor crystallization, using sodium sulfate and PEG-2000. At sufficiently high concentrations of PEG, a second phase was generated in which the protein crystallization occurred simultaneously. The single chain antibody crystals were partitioned to the top, polyethylene glycol-rich phase. The crystal nucleation took place in the sodium sulfate-rich phase and at the phase boundary, whereas crystal growth was progressing mainly in the polyethylene glycol-rich phase. The crystals in the polyethylene glycol-rich phase grew to a size of >50 µm. Additionally, polyethylene glycol acted as an anti-solvent, thus, it influenced the crystallization yield. A phase diagram with an undersaturation zone, crystallization area, and amorphous precipitation zone was established. Only small differences in polyethylene glycol concentration caused significant shifts of the crystallization yield. An increase of the polyethylene glycol content from 2% (w/v) to 4% (w/v) increased the yield from approximately 63-87%, respectively. Our results show that crystallization in aqueous two-phase systems is an opportunity to foster process integration. © 2014 Wiley Periodicals, Inc.

Balancing Agile Combat Support Manpower to Better Meet the Future Security Environment

DTIC Science & Technology

2014-01-01

for a 3,000-person deployment package. 6 Figure 1.1 Postured Manpower Included in This Analysis NOTE: Spc = space, Avn = aviation, MX...an po w er ,  1 00 0s USAF  postured  manpower Spc,   Avn ,  Mx,  Intel Other  ACS Our  scope 7 • In Chapter Four, we discuss several

Quality Space and Launch Requirements Addendum to AS9100C

DTIC Science & Technology

2015-03-05

45 8.9.1 Statistical Process Control (SPC) .......................................................................... 45 8.9.1.1 Out of Control...Systems Center SME Subject Matter Expert SOW Statement of Work SPC Statistical Process Control SPO System Program Office SRP Standard Repair...individual data exceeding the control limits. Control limits are developed using standard statistical methods or other approved techniques and are based on

Project T.E.A.M. (Technical Education Advancement Modules). Introduction to Statistical Process Control.

ERIC Educational Resources Information Center

Billings, Paul H.

This instructional guide, one of a series developed by the Technical Education Advancement Modules (TEAM) project, is a 6-hour introductory module on statistical process control (SPC), designed to develop competencies in the following skill areas: (1) identification of the three classes of SPC use; (2) understanding a process and how it works; (3)…

Using a statistical process control chart during the quality assessment of cancer registry data.

PubMed

Myles, Zachary M; German, Robert R; Wilson, Reda J; Wu, Manxia

2011-01-01

Statistical process control (SPC) charts may be used to detect acute variations in the data while simultaneously evaluating unforeseen aberrations that may warrant further investigation by the data user. Using cancer stage data captured by the Summary Stage 2000 (SS2000) variable, we sought to present a brief report highlighting the utility of the SPC chart during the quality assessment of cancer registry data. Using a county-level caseload for the diagnosis period of 2001-2004 (n=25,648), we found the overall variation of the SS2000 variable to be in control during diagnosis years of 2001 and 2002, exceeded the lower control limit (LCL) in 2003, and exceeded the upper control limit (UCL) in 2004; in situ/localized stages were in control throughout the diagnosis period, regional stage exceeded UCL in 2004, and distant stage exceeded the LCL in 2001 and the UCL in 2004. Our application of the SPC chart with cancer registry data illustrates that the SPC chart may serve as a readily available and timely tool for identifying areas of concern during the data collection and quality assessment of central cancer registry data.

Control chart applications in healthcare: a literature review

NASA Astrophysics Data System (ADS)

Suman, Gaurav; Prajapati, DeoRaj

2018-05-01

The concept of Statistical process control (SPC) was given by the physicist Walter Shewhart in order to improve the industrial manufacturing. The SPC was firstly applied in laboratory and after then shifted to patient level in hospitals. As there is more involvement of human in healthcare, the chances of errors are also more. SPC i.e., control chart can help in determining the source of errors by identifying the special and common causes of variations. This paper presents the review of literature on the application of SPC and control chart in healthcare sector. Forty articles are selected out of 142 potentially relevant searched studies. Selected studies are categorised into eight departments. Literature survey shows that most of work on control chart applications in healthcare is carried out in Surgery, Emergency and Epidemiology departments. US, UK and Australia are the main customers where maximum amount of work was done. The US is the country where control chart in healthcare sector have been used at regular interval. This shows the gap of deploying control chart in different departments and different countries as well. The CUSUM and EWMA chart came into picture in healthcare sector after 2008 and are used at regular interval.

SpcAudace: Spectroscopic processing and analysis package of Audela software

NASA Astrophysics Data System (ADS)

Mauclaire, Benjamin

2017-11-01

SpcAudace processes long slit spectra with automated pipelines and performs astrophysical analysis of the latter data. These powerful pipelines do all the required steps in one pass: standard preprocessing, masking of bad pixels, geometric corrections, registration, optimized spectrum extraction, wavelength calibration and instrumental response computation and correction. Both high and low resolution long slit spectra are managed for stellar and non-stellar targets. Many types of publication-quality figures can be easily produced: pdf and png plots or annotated time series plots. Astrophysical quantities can be derived from individual or large amount of spectra with advanced functions: from line profile characteristics to equivalent width and periodogram. More than 300 documented functions are available and can be used into TCL scripts for automation. SpcAudace is based on Audela open source software.

Concentrated aqueous sodium chloride solution in clays at thermodynamic conditions of hydraulic fracturing: Insight from molecular dynamics simulations

NASA Astrophysics Data System (ADS)

Svoboda, Martin; Lísal, Martin

2018-06-01

To address a high salinity of flow-back water during hydraulic fracturing, we use molecular dynamics (MD) simulations and study the thermodynamics, structure, and diffusion of concentrated aqueous salt solution in clay nanopores. The concentrated solution results from the dissolution of a cubic NaCl nanocrystal, immersed in an aqueous NaCl solution of varying salt concentration and confined in clay pores of a width comparable to the crystal size. The size of the nanocrystal equals to about 18 Å which is above a critical nucleus size. We consider a typical shale gas reservoir condition of 365 K and 275 bar, and we represent the clay pores as pyrophyllite and Na-montmorillonite (Na-MMT) slits. We employ the Extended Simple Point Charge (SPC/E) model for water, Joung-Cheatham model for ions, and CLAYFF for the slit walls. We impose the pressure in the normal direction and the resulting slit width varies from about 20 to 25 Å when the salt concentration in the surrounding solution increased from zero to an oversaturated value. By varying the salt concentration, we observe two scenarios. First, the crystal dissolves and its dissolution time increases with increasing salt concentration. We describe the dissolution process in terms of the number of ions in the crystal, and the crystal size and shape. Second, when the salt concentration reaches a system solubility limit, the crystal grows and attains a new equilibrium size; the crystal comes into equilibrium with the surrounding saturated solution. After crystal dissolution, we carry out canonical MD simulations for the concentrated solution. We evaluate the hydration energy, density profiles, orientation distributions, hydrogen-bond network, radial distribution functions, and in-plane diffusion of water and ions to provide insight into the microscopic behaviour of the concentrated aqueous sodium chloride solution in interlayer galleries of the slightly hydrophobic pyrophyllite and hydrophilic Na-MMT pores.

Concentrated aqueous sodium chloride solution in clays at thermodynamic conditions of hydraulic fracturing: Insight from molecular dynamics simulations.

PubMed

Svoboda, Martin; Lísal, Martin

2018-06-14

To address a high salinity of flow-back water during hydraulic fracturing, we use molecular dynamics (MD) simulations and study the thermodynamics, structure, and diffusion of concentrated aqueous salt solution in clay nanopores. The concentrated solution results from the dissolution of a cubic NaCl nanocrystal, immersed in an aqueous NaCl solution of varying salt concentration and confined in clay pores of a width comparable to the crystal size. The size of the nanocrystal equals to about 18 Å which is above a critical nucleus size. We consider a typical shale gas reservoir condition of 365 K and 275 bar, and we represent the clay pores as pyrophyllite and Na-montmorillonite (Na-MMT) slits. We employ the Extended Simple Point Charge (SPC/E) model for water, Joung-Cheatham model for ions, and CLAYFF for the slit walls. We impose the pressure in the normal direction and the resulting slit width varies from about 20 to 25 Å when the salt concentration in the surrounding solution increased from zero to an oversaturated value. By varying the salt concentration, we observe two scenarios. First, the crystal dissolves and its dissolution time increases with increasing salt concentration. We describe the dissolution process in terms of the number of ions in the crystal, and the crystal size and shape. Second, when the salt concentration reaches a system solubility limit, the crystal grows and attains a new equilibrium size; the crystal comes into equilibrium with the surrounding saturated solution. After crystal dissolution, we carry out canonical MD simulations for the concentrated solution. We evaluate the hydration energy, density profiles, orientation distributions, hydrogen-bond network, radial distribution functions, and in-plane diffusion of water and ions to provide insight into the microscopic behaviour of the concentrated aqueous sodium chloride solution in interlayer galleries of the slightly hydrophobic pyrophyllite and hydrophilic Na-MMT pores.

[Influence of compliance on the incidence of cardiovascular events and health costs when using single-pill fixed-dose combinations for the treatment of hypertension].

PubMed

Sicras Mainar, Antoni; Galera Llorca, Jordi; Muñoz Ortí, Genís; Navarro Artieda, Ruth

2011-02-26

To determine the incidence of cardiovascular events (CVE) and health care costs in relation to compliance, persistence and level of blood pressure control when comparing patients treated with single-pill combinations (SPC) or free combinations (FC) for the treatment of hypertension. Observational, multicenter study that included patients>30 years old, from six primary care teams and two hospitals, who started pharmacological treatment for hypertension during 2006. Two study groups were established: SPC (ACEIs/diuretics; ARBs/diuretics) and FC (ACEIs+DIU; ARB+DIU, separately). Main variables studied were sociodemographic data, comorbidity, Charlson-index, compliance, persistence and achievement of therapeutic goals (ESH-ESC criteria). The cumulative incidence of CVE and a total-cost model were determined (differentiating: health/direct; non-health/indirect). Patients were followed for two years. Statistical analysis included logistic regression, Cox proportional hazards model and analysis of covariance. Statistical signification: p<0.05. 1,605 patients were recruited, 1,112 (69.3%) receiving SPC and 493 (30.7%) receiving FC, p<0.001; mean age: 69.4 (12.2) years; women: 55.5%. FC treatments were associated with ischaemic heart disease (OR=1.4; 95% CI: 1.1-2.0) and organ failure (OR=1.5; 95% CI: 1.2-2.1), p<0.031. Patients on SPC showed better therapeutic compliance (77.6% vs 71.9%; p<0.001) and longer persistence of treatment (62.1% on-treatment at 24-months [95% CI: 56.3-67.9] vs 49.7% [95% CI: 38.5-60.9]; p<0.001). Optimal control of blood pressure was higher in SPC (48.9% [95% CI: 43.0-54.8] vs 46.7% [95% CI: 35.6-57.8]; p<0.001). Cumulative incidence of cerebrovascular accidents in FC was 4.6% vs 2.4% in SPC; p=0.041. The total health care costs were lower in SPC (1,650.7 € vs 1,674.8 €; p<0.001), including lower specialized care costs (316.1 € vs 382.9 €; p<0.001), fewer hospital admissions and less loss of labour productivity (44.5 € vs 88.4 €; p<0.001). Better compliance and persistence with antihypertensive fixed-dose combinations improves therapeutic control, leading to a significant reduction of cerebrovascular accidents and total health care costs. Copyright © 2009 Elsevier España, S.L. All rights reserved.

Prostate Cancer Clinical Trials Group - The University of Michigan Site

DTIC Science & Technology

2014-06-01

Medicine and Urology University of Michigan Comprehensive Cancer Center Internal Medicine , Hematology Oncology 7314 Cancer Center, SPC 5946 Ann...Arbor, MI 48109-5946 mahahuss@umich.edu David C. Smith, M.D., FACP, Professor, Departments of Internal Medicine and Urology University of Michigan...Comprehensive Cancer Center Internal Medicine , Hematology Oncology 7302 Cancer Center, SPC 5946 Ann Arbor, MI 48109-5946 dcsmith@umich.edu

SU-F-T-107: Correlations Between Dosimetric Indices of Pharyngeal Constrictors and Proximal Esophagus with Associated Patient-Reported Outcomes Six Months After Radiation Therapy for Head and Neck Cancer

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

Chera, B; Price, A; Kostich, M

Purpose: To compare the correlations between different dosimetric indices derived from the pharyngeal constrictor muscles and proximal esophagus with patient-reported difficulty in swallowing 6 months post radiotherapy using a novel patient reported outcome version of CTCAE (PRO-CTCAE). Methods: Forty-three patients with oropharyngeal squamous cell carcinoma were treated on a prospective multi-institutional study. All patients received de-intensified 60 Gy intensity modulated radiotherapy. We investigated correlations of individual patient dosimetric data of the superior (SPC), middle (MPC), inferior (IPC) pharyngeal constrictor muscles, the superior esophagus (SES), and the inferior esophagus (IES) to their self-reported 6 month post-treatment swallowing difficulty responses. Mild (≥more » Grade 1) swallowing difficulty responses were used as the clinical endpoint indicating response. The predictive efficacy of Dmean and dose-volume (VD) points were assessed through the area under the Receiver Operating Characteristic curve (ROC) and Odds Ratio (OR). Results: The SES and SPC had more favorable area under the curves (AUC) for the Dmean (0.62 and 0.70) while the Dmean to the IPC, MPC, and IES produced suboptimal AUCs (0.42, 0.48, and 0.52). Additionally, over the range of VD, the V54 and V55 for the SES and SPC demonstrated the highest AUCs: AUC(SES) = 0.76–0.73 and AUC(SPC) = 0.72–0.69, respectively. The IES, IPC, and MPC had worse AUC results over the range of VD. An optimal OR can be found when V54 = 96% for the SPC, where OR = 3.96 (1.07–14.62). Conclusion: The V45 and V55 of the SES and SPC had the highest correlation to the clinical endpoint compared to the commonly used dosimetric index, Dmean for both the esophagus and constrictor muscles. The reported dosimetric data demonstrates that new dosimetric indices may need to be considered in the setting of dose de-escalation and self-reported outcomes.« less

SPCOLA: Combining laser altimetry and stereophotoclinometery to obtain topography for Bennu

NASA Astrophysics Data System (ADS)

Roberts, J. H.; Barnouin, O. S.; Palmer, E. E.; Gaskell, R. W.; Weirich, J. R.; Daly, M. G.; Seabrook, J.; Nair, H.; Espiritu, R. C.; Lauretta, D. S.; Perry, M. E.

2017-12-01

The Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) mission will return pristine samples of carbonaceous material from the surface of asteroid (101955) Bennu. Two instruments on OSIRIS-REx enable independent determination of topography: the OSIRIS-REx Laser Altimeter (OLA) and the OSIRIS-REx Camera Suite (OCAMS). OLA is a scanning lidar that ranges to the surface, returning altimetry information. OCAMS returns imaging data that are used to perform stereophotoclinometery (SPC) on these images to construct slope and albedo "maplets", small patches of the surface with central control points. Here we present a technique to combine topographic maplets generated using SPC with a compatible set of "mapolas" generated from OLA data. This "SPCOLA" process leverages the strengths of both while mitigating their respective weaknesses. A key advantage of SPC is that it allows a solution of the topography at accuracies similar to those of the best images used. SPC can make use of images at a wide range of viewing geometries and resolutions to simultaneously solve for slope and albedo. SPC also provides precise control point location from large stereo separation over multiple trajectories and can fill in gaps where point-based lidar data may not exist. Key strengths of lidar ranging include the ability to operate under any illumination conditions (including in the dark), insensitivity to albedo variations, robustness over large changes in slope, and provision of an absolute measurement of the range constraint to the surface. This range can be used to derive a control network for SPC, to improve the knowledge of the spacecraft position, to provide an independent scale for imagery and spectral data, and to provide constraints for any gravity solution obtained with radio science. Our goal in combining OLA data sets with image-based data is to generate Digital Elevation Models (DEMs) with higher accuracy than those using either data set alone. However, this combination requires careful coordination to ensure compatible formats, and some care in appropriately weighting them to achieve meaningful improvement of the DEMs.

Development of Statistical Process Control Methodology for an Environmentally Compliant Surface Cleaning Process in a Bonding Laboratory

NASA Technical Reports Server (NTRS)

Hutchens, Dale E.; Doan, Patrick A.; Boothe, Richard E.

1997-01-01

Bonding labs at both MSFC and the northern Utah production plant prepare bond test specimens which simulate or witness the production of NASA's Reusable Solid Rocket Motor (RSRM). The current process for preparing the bonding surfaces employs 1,1,1-trichloroethane vapor degreasing, which simulates the current RSRM process. Government regulations (e.g., the 1990 Amendments to the Clean Air Act) have mandated a production phase-out of a number of ozone depleting compounds (ODC) including 1,1,1-trichloroethane. In order to comply with these regulations, the RSRM Program is qualifying a spray-in-air (SIA) precision cleaning process using Brulin 1990, an aqueous blend of surfactants. Accordingly, surface preparation prior to bonding process simulation test specimens must reflect the new production cleaning process. The Bonding Lab Statistical Process Control (SPC) program monitors the progress of the lab and its capabilities, as well as certifies the bonding technicians, by periodically preparing D6AC steel tensile adhesion panels with EA-91 3NA epoxy adhesive using a standardized process. SPC methods are then used to ensure the process is statistically in control, thus producing reliable data for bonding studies, and identify any problems which might develop. Since the specimen cleaning process is being changed, new SPC limits must be established. This report summarizes side-by-side testing of D6AC steel tensile adhesion witness panels and tapered double cantilevered beams (TDCBs) using both the current baseline vapor degreasing process and a lab-scale spray-in-air process. A Proceco 26 inches Typhoon dishwasher cleaned both tensile adhesion witness panels and TDCBs in a process which simulates the new production process. The tests were performed six times during 1995, subsequent statistical analysis of the data established new upper control limits (UCL) and lower control limits (LCL). The data also demonstrated that the new process was equivalent to the vapor degreasing process.

Comments on "Adaptive resolution simulation in equilibrium and beyond" by H. Wang and A. Agarwal

NASA Astrophysics Data System (ADS)

Klein, R.

2015-09-01

Wang and Agarwal (Eur. Phys. J. Special Topics, this issue, 2015, doi: 10.1140/epjst/e2015-02411-2) discuss variants of Adaptive Resolution Molecular Dynamics Simulations (AdResS), and their applications. Here we comment on their report, addressing scaling properties of the method, artificial forcings implemented to ensure constant density across the full simulation despite changing thermodynamic properties of the simulated media, the possible relation between an AdResS system on the one hand and a phase transition phenomenon on the other, and peculiarities of the SPC/E water model.

[Physician versus 'off-label" ordinance].

PubMed

Kordus, Katarzyna; Spiewak, Radosław

2015-01-01

Polish physicians are obliged by legislation to prescribe drugs authorized for the sale in the Republic of Poland, based on registration documentation, including the Summaries of Product Characteristics (SPC). So called 'off label' treatment occurs in case of the conflict between prescription and information contained in the SPC, which may be considered as a 'medical experiment'. In case of adverse drug reactions, such classification excludes the responsibility of the marketing authorization holders, and damages are not covered by obligatory third party insurance, which can pose financial and legal consequences to the doctor. Deviations from SPC-compliant prescription may include a different way of drug administration, drug administration compliant with the indications yet in patients for whom there is no specified drug dosage, or in case of an indication not contained in the SPC. Medicinal products with equivalent active component, form and dose can have different registration indications in the SPC, and the actively promoted dispensation of less expensive substitutes by the pharmacists may, against doctor's will, result in the use that is non-compliant with registration of the substitute drug. Pharmacotherapy of 'orphan diseases', for which there are no registered medicinal products, also becomes an essential issue as it forces doctors into 'off-label' prescriptions. Moreover, the reimbursement of drugs in most cases is limited to medicinal products that are prescribed according to the registration indications. The pleas by medical professionals to make ordination and reimbursement of drugs depend on active pharmaceutical ingredient and evidence of efficacy, as well as to introduce Evidence Based Medicine (EBM) standards for the treatment of diseases, did not receive proper attention from the governing bodies. Therefore, a fundamental question remains unanswered as to what should be the principal gauge for physicians' therapeutic decision: the ethics, conscience, recent scientific evidence or legal and administrative regulations?

Stability of kinetochore-microtubule attachment and the role of different KMN network components in Drosophila.

PubMed

Feijão, Tália; Afonso, Olga; Maia, André F; Sunkel, Claudio E

2013-10-01

Kinetochores bind spindle microtubules and also act as signaling centers that monitor this interaction. Defects in kinetochore assembly lead to chromosome missegregation and aneuploidy. The interaction between microtubules and chromosomes involves a conserved super-complex of proteins, known as the KNL1Mis12Ndc80 (KMN) network, composed by the KNL1 (Spc105), Mis12, and Ndc80 complexes. Previous studies indicate that all components of the network are required for kinetochore-microtubule attachment and all play relevant functions in chromosome congression, biorientation, and segregation. Here, we report a comparative study addressing the role of the different KMN components using dsRNA and in vivo fluorescence microscopy in Drosophila S2 cells allowing us to suggest that different KMN network components might perform different roles in chromosome segregation and the mitotic checkpoint signaling. Depletion of different components results in mostly lateral kinetochore-microtubule attachments that are relatively stable on depletion of Mis12 or Ndc80 but very unstable after Spc105 depletion. In vivo analysis on depletion of Mis12, Ndc80, and to some extent Spc105, shows that lateral kinetochore-microtubule interactions are still functional allowing poleward kinetochore movement. We also find that different KMN network components affect differently the localization of spindle assembly checkpoint (SAC) proteins at kinetochores. Depletion of Ndc80 and Spc105 abolishes the mitotic checkpoint, whereas depletion of Mis12 causes a delay in mitotic progression. Taken together, our results suggest that Mis12 and Ndc80 complexes help to properly orient microtubule attachment, whereas Spc105 plays a predominant role in the kinetochore-microtubule attachment as well as in the poleward movement of chromosomes, SAC response, and cell viability. Copyright © 2013 Wiley Periodicals, Inc.

A new approach to process control using Instability Index

NASA Astrophysics Data System (ADS)

Weintraub, Jeffrey; Warrick, Scott

2016-03-01

The merits of a robust Statistical Process Control (SPC) methodology have long been established. In response to the numerous SPC rule combinations, processes, and the high cost of containment, the Instability Index (ISTAB) is presented as a tool for managing these complexities. ISTAB focuses limited resources on key issues and provides a window into the stability of manufacturing operations. ISTAB takes advantage of the statistical nature of processes by comparing the observed average run length (OARL) to the expected run length (ARL), resulting in a gap value called the ISTAB index. The ISTAB index has three characteristic behaviors that are indicative of defects in an SPC instance. Case 1: The observed average run length is excessively long relative to expectation. ISTAB > 0 is indicating the possibility that the limits are too wide. Case 2: The observed average run length is consistent with expectation. ISTAB near zero is indicating that the process is stable. Case 3: The observed average run length is inordinately short relative to expectation. ISTAB < 0 is indicating that the limits are too tight, the process is unstable or both. The probability distribution of run length is the basis for establishing an ARL. We demonstrate that the geometric distribution is a good approximation to run length across a wide variety of rule sets. Excessively long run lengths are associated with one kind of defect in an SPC instance; inordinately short run lengths are associated with another. A sampling distribution is introduced as a way to quantify excessively long and inordinately short observed run lengths. This paper provides detailed guidance for action limits on these run lengths. ISTAB as a statistical method of review facilitates automated instability detection. This paper proposes a management system based on ISTAB as an enhancement to more traditional SPC approaches.

Tetrachloroethene degradation by reducing-agent enhanced Fe(II)/Fe(III) catalyzed percarbonate

NASA Astrophysics Data System (ADS)

Miao, Z.; Brusseau, M. L.; Lu, S.; Gu, X.; Yan, N.; Qiu, Z.; Sui, Q.

2015-12-01

This project investigated the effect of reducing agents on the degradation of tetrachloroethene(PCE) by Fe(II)/Fe(III) catalyzed sodium percarbonate (SPC). SPC possesses similar function as liquid H2O2, such that free H2O2 is released into solution when percarbonate is mixed with water. The addition of reducing agents, including hydroxylamine hydrochloride, sodium sulfite, ascorbic acid and sodium ascorbate, accelerated the Fe(III)/Fe(II) redoxcycle, leading to a relatively steady Fe(II) concentration and higher production of free radicals. This, in turn, resulted in enhanced PCE oxidation by SPC, with almost complete PCE removal obtained for appropriate Fe and SPC concentrations.The results of chemical probe tests, using nitrobenzene and carbon tetrachloride, demonstrated that HO● was the predominant radical in the system and that O2●-played a minor role. This was further confirmed by the results of electron paramagnetic resonance measurements and salicylic acid hydroxylationanalysis by high performance liquid chromatography(HPLC). PCE degradation decreased significantly with the addition of isopropanol, a strong HO● scavenger, supporting the hypothesis that HO● was primarily responsible for PCE degradation. It should be noted that the release of Cl- was slightly delayed in the first 20 mins, indicating that intermediate products were produced. However, gas chromatography mass spectrometry (GC/MS) analysis did not detect any chlorinated organic compound except PCE, indicating these intermediates were quickly degraded, which resulted in the complete conversion of PCE to CO2. In conclusion, the use of reducing agents to enhance Fe(II)/Fe(III) catalyzed SPC oxidation appears to be a promising approach for the rapid degradation of organic contaminants in groundwater.

Identification of cancer initiating cells in K-Ras driven lung adenocarcinoma.

PubMed

Mainardi, Sara; Mijimolle, Nieves; Francoz, Sarah; Vicente-Dueñas, Carolina; Sánchez-García, Isidro; Barbacid, Mariano

2014-01-07

Ubiquitous expression of a resident K-Ras(G12V) oncogene in adult mice revealed that most tissues are resistant to K-Ras oncogenic signals. Indeed, K-Ras(G12V) expression only induced overt tumors in lungs. To identify these transformation-permissive cells, we induced K-Ras(G12V) expression in a very limited number of adult lung cells (0.2%) and monitored their fate by X-Gal staining, a surrogate marker coexpressed with the K-Ras(G12V) oncoprotein. Four weeks later, 30% of these cells had proliferated to form small clusters. However, only SPC(+) alveolar type II (ATII) cells were able to form hyperplastic lesions, some of which progressed to adenomas and adenocarcinomas. In contrast, induction of K-Ras(G12V) expression in lung cells by intratracheal infection with adenoviral-Cre particles generated hyperplasias in all regions except the proximal airways. Bronchiolar and bronchioalveolar duct junction hyperplasias were primarily made of CC10(+) Clara cells. Some of them progressed to form benign adenomas. However, only alveolar hyperplasias, exclusively made up of SPC(+) ATII cells, progressed to yield malignant adenocarcinomas. Adenoviral infection induced inflammatory infiltrates primarily made of T and B cells. This inflammatory response was essential for the development of K-Ras(G12V)-driven bronchiolar hyperplasias and adenomas, but not for the generation of SPC(+) ATII lesions. Finally, activation of K-Ras(G12V) during embryonic development under the control of a Sca1 promoter yielded CC10(+), but not SPC(+), hyperplasias, and adenomas. These results, taken together, illustrate that different types of lung cells can generate benign lesions in response to K-Ras oncogenic signals. However, in adult mice, only SPC(+) ATII cells were able to yield malignant adenocarcinomas.

Estimating the Time to Benefit for Preventive Drugs with the Statistical Process Control Method: An Example with Alendronate.

PubMed

van de Glind, Esther M M; Willems, Hanna C; Eslami, Saeid; Abu-Hanna, Ameen; Lems, Willem F; Hooft, Lotty; de Rooij, Sophia E; Black, Dennis M; van Munster, Barbara C

2016-05-01

For physicians dealing with patients with a limited life expectancy, knowing the time to benefit (TTB) of preventive medication is essential to support treatment decisions. The aim of this study was to investigate the usefulness of statistical process control (SPC) for determining the TTB in relation to fracture risk with alendronate versus placebo in postmenopausal women. We performed a post hoc analysis of the Fracture Intervention Trial (FIT), a randomized, controlled trial that investigated the effect of alendronate versus placebo on fracture risk in postmenopausal women. We used SPC, a statistical method used for monitoring processes for quality control, to determine if and when the intervention group benefited significantly more than the control group. SPC discriminated between the normal variations over time in the numbers of fractures in both groups and the variations that were attributable to alendronate. The TTB was defined as the time point from which the cumulative difference in the number of clinical fractures remained greater than the upper control limit on the SPC chart. For the total group, the TTB was defined as 11 months. For patients aged ≥70 years, the TTB was 8 months [absolute risk reduction (ARR) = 1.4%]; for patients aged <70 years, it was 19 months (ARR = 0.7%). SPC is a clear and understandable graphical method to determine the TTB. Its main advantage is that there is no need to define a prespecified time point, as is the case in traditional survival analyses. Prescribing alendronate to patients who are aged ≥70 years is useful because the TTB shows that they will benefit after 8 months. Investigators should report the TTB to simplify clinical decision making.

[Houttuynia Cordata induces expression of human beta-defensin-2 mRNA in pulmonary epithelial cells in vitro].

PubMed

Luo, Li; Dong, Bi-rong; Teng, Li-hua

2008-07-01

To explore the effects of Houttuynia Cordata on expression of human beta-defensin-2 (HBD-2) in pulmonary epithelial cells (SPC-A-1) in vitro; and to observe the correlationship between the level of HBD-2 mRNA and the concentrations or treatment times of Houttuynia Cordata. The SPC-A-1 cells were cultured with different concentrations of Houttuynia Cordata in vitro, including 0, 12.5, 25, 50, 100 and 200 microg/ml. And then, the SPC-A-1 cells were cultured with the optimal concentration of Houttuynia Cordata in different lengths of time, including 1, 2, 4, 8, 16 and 24 hours. After the treatment, the mRNA level of HBD-2 in pulmonary epithelial cells was detected by means of semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). After being cultured with Houttuynia Cordata, the expression of HBD-2 mRNA had positive correlation with the stimulus concentrations (rs=0.829, P=0.042) and stimulus time (rs=0.914, P=0.003). The highest expression of HBD-2 mRNA was induced by 100 microg/ml Houttuynia Cordata after 8-hour treatment. In comparison with the normal control group and the interleukin-1beta group, 100 microg/ml Houttuynia Cordata could significantly up-regulate the expression of HBD-2 mRNA in SPC-A-1 cells after 8-hour treatment (P<0.01). Houttuynia Cordata can up-regulate expression of HBD-2 mRNA in SPC-A-1 cells, and the highest expression level of HBD-2 mRNA can be obtained by culture with 100 microg/ml Houttuynia Cordata for 8 hours.

Prospective short-term feasibility study of perioperative suprapubic catheters in laparoscopic colectomy.

PubMed

Nagao, Sayaka; Saida, Yoshihisa; Enomoto, Toshiyuki; Takahashi, Asako; Higuchi, Tadashi; Moriyama, Hodaka; Niituma, Toru; Watanabe, Manabu; Asai, Koji; Kusachi, Shinya

2018-05-16

Here we report a prospective study on whether a temporary suprapubic catheter (SPC) can be safely inserted as a substitute for transurethral balloon catheterization during laparoscopy-assisted colectomy. Our subjects included 52 cases who gave informed consent to have an SPC inserted. These subjects were selected from cases who underwent laparoscopy-assisted surgery for primary colorectal cancer from October 2014 to August 2015. An SPC was inserted into 45 of the original 52 cases. The median surgical duration was 220 min (range, 11-438 min), and the SPC insertion was performed at a median of 133 min (range, 9-384 min) after the start of surgery. Insertion required a median duration of 116 s. In one case (2.2%), the bladder was perforated by the paracentesis needle, and in two cases (4.4%), hematuria was observed at the time of insertion; however, surgery was completed without any incident in these three cases. Six of the remaining 42 cases (13.3%) demonstrated neither micturition desire nor independent urination on the day the catheter was clamped. In these cases, the clamp was released two to four times, and draining of an average of 586-mL urine, micturition desire, and independent urination were confirmed 2-4 days later. Transurethral balloon catheterization is a simple procedure that is commonly used on surgical patients, but it can cause pain, discomfort, and infection. In contrast, SPC insertion is a procedure that avoids crossing the urethra and its associated disadvantages. Here we were able to demonstrate that the procedure can be safely used in laparoscopic surgery patients. © 2018 Japan Society for Endoscopic Surgery, Asia Endosurgery Task Force and John Wiley & Sons Australia, Ltd.

Role of the superior pharyngeal constrictor muscle in forced breathing in dogs.

PubMed

Yaman, Z; Kogo, M; Senoo, H; Iida, S; Ishii, S; Matsuya, T

2000-03-01

Respiratory-related electromyographic (EMG) activity of the superior pharyngeal constrictor (SPC) muscle was analyzed during the early stage of forced breathing. Four adult dogs anesthetized with sodium pentobarbital were used. In the first part of the study, oral and nasal breathing tubes were placed into the respective cavities, and a tracheotomy tube was placed in the second part of the study. Two conditions, the presence (oral-nasal tube breathing) and absence (tracheotomy breathing) of airflow in the upper airway, were achieved in each dog. Following quiet breathing, animals were connected to a closed breathing system, first by an oral-nasal tube and then by a tracheotomy tube. We proposed to induce a forced breathing condition mechanically by using this system for 1 minute. We increased resistance to airflow during forced breathing by means of connecting tubes and a bag. Our aim was not to produce chemical drive but to produce a forced respiration by increasing the resistance to airflow. Tidal volume, breathing frequency, minute volume, chest wall movement, and EMG activity of the SPC muscle were measured and analyzed. During quiet breathing through an oral-nasal or tracheotomy tube, low-amplitude EMG activity of the SPC muscle corresponding to the expiratory cycle of the respiration was observed. In both study conditions, phasic expiratory EMG activity increased immediately after the advent of the breathing from the closed system. Tidal volumes and frequencies also increased rapidly during forced breathing. An increase in the resistance to airflow increased the activity of the SPC muscle. This augmented respiratory activity probably assists the patency of the upper airway. The augmented respiratory activity was independent of the local reflex pathways. Respiratory-related activity of the SPC muscle may help dilate and stiffen the pharyngeal airway, promoting airway patency.

Dietary soybean protein concentrate-induced intestinal disorder in marine farmed Atlantic salmon, Salmo salar is associated with alterations in gut microbiota.

PubMed

Green, Timothy J; Smullen, Richard; Barnes, Andrew C

2013-09-27

The aquaculture industry has made substantial progress in reducing the fishmeal content of feeds for carnivorous species, driven by demand for improved sustainability and reduced cost. Soybean protein concentrate (SPC) is an attractive replacement for fishmeal, but intestinal disorders have been reported in Atlantic salmon (Salmo salar) fed these diets at high seawater temperatures, with preliminary evidence suggesting SPC induces these disorders by altering the intestinal microbiota. We compared the intestinal microbiota of marine-farmed S. salar fed experimental diets with varying levels of SPC in mid- and late-summer. Terminal restriction fragment length polymorphism (T-RFLP) and 16S rRNA clone library analysis revealed the microbiota adherent to the intestinal tract of salmon is complex at the population level, but simple and highly variable at the individual level. Temporal changes were observed with the bacterial diversity increasing in the intestinal tract in late summer. A Verrucomicrobia was the most frequently observed ribotype in early summer, whilst an Aliivibrio was the most frequently observed ribotype in late summer. Feeding SPC to salmon increased the bacterial diversity of the intestinal tract and resulted in the presence of bacteria not normally associated with marine fish (Escherichia and Propionibacterium). These diet-induced changes to the intestinal-microbiome could be ameliorated by inclusion of a prebiotic (mannan-oligosaccharide or MOS) to the diet. None of the experimental diets induced inflammation of the intestine as assessed by histopathology and expression of inflammatory cytokines. Our results support the "dysbiosis" hypothesis that SPC adversely affects the intestinal microbiota of Atlantic salmon. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

Interfacial thermodynamics of water and six other liquid solvents.

PubMed

Pascal, Tod A; Goddard, William A

2014-06-05

We examine the thermodynamics of the liquid-vapor interface by direct calculation of the surface entropy, enthalpy, and free energy from extensive molecular dynamics simulations using the two-phase thermodynamics (2PT) method. Results for water, acetonitrile, cyclohexane, dimethyl sulfoxide, hexanol, N-methyl acetamide, and toluene are presented. We validate our approach by predicting the interfacial surface tensions (IFT--excess surface free energy per unit area) in excellent agreement with the mechanical calculations using Kirkwood-Buff theory. Additionally, we evaluate the temperature dependence of the IFT of water as described by the TIP4P/2005, SPC/Ew, TIP3P, and mW classical water models. We find that the TIP4P/2005 and SPC/Ew water models do a reasonable job of describing the interfacial thermodynamics; however, the TIP3P and mW are quite poor. We find that the underprediction of the experimental IFT at 298 K by these water models results from understructured surface molecules whose binding energies are too weak. Finally, we performed depth profiles of the interfacial thermodynamics which revealed long tails that extend far into what would be considered bulk from standard Gibbs theory. In fact, we find a nonmonotonic interfacial free energy profile for water, a unique feature that could have important consequences for the absorption of ions and other small molecules.

Modified SPC for short run test and measurement process in multi-stations

NASA Astrophysics Data System (ADS)

Koh, C. K.; Chin, J. F.; Kamaruddin, S.

2018-03-01

Due to short production runs and measurement error inherent in electronic test and measurement (T&M) processes, continuous quality monitoring through real-time statistical process control (SPC) is challenging. Industry practice allows the installation of guard band using measurement uncertainty to reduce the width of acceptance limit, as an indirect way to compensate the measurement errors. This paper presents a new SPC model combining modified guard band and control charts (\\bar{\\text{Z}} chart and W chart) for short runs in T&M process in multi-stations. The proposed model standardizes the observed value with measurement target (T) and rationed measurement uncertainty (U). S-factor (S f) is introduced to the control limits to improve the sensitivity in detecting small shifts. The model was embedded in automated quality control system and verified with a case study in real industry.

Structure and dynamics of complex liquid water: Molecular dynamics simulation

NASA Astrophysics Data System (ADS)

S, Indrajith V.; Natesan, Baskaran

2015-06-01

We have carried out detailed structure and dynamical studies of complex liquid water using molecular dynamics simulations. Three different model potentials, namely, TIP3P, TIP4P and SPC-E have been used in the simulations, in order to arrive at the best possible potential function that could reproduce the structure of experimental bulk water. All the simulations were performed in the NVE micro canonical ensemble using LAMMPS. The radial distribution functions, gOO, gOH and gHH and the self diffusion coefficient, Ds, were calculated for all three models. We conclude from our results that the structure and dynamical parameters obtained for SPC-E model matched well with the experimental values, suggesting that among the models studied here, the SPC-E model gives the best structure and dynamics of bulk water.

Direct Coexistence Methods to Determine the Solubility of Salts in Water from Numerical Simulations. Test Case NaCl.

PubMed

Manzanilla-Granados, Héctor M; Saint-Martín, Humberto; Fuentes-Azcatl, Raúl; Alejandre, José

2015-07-02

The solubility of NaCl, an equilibrium between a saturated solution of ions and a solid with a crystalline structure, was obtained from molecular dynamics simulations using the SPC/E and TIP4P-Ew water models. Four initial setups on supersaturated systems were tested on sodium chloride (NaCl) solutions to determine the equilibrium conditions and computational performance: (1) an ionic solution confined between two crystal plates of periodic NaCl, (2) a solution with all the ions initially distributed randomly, (3) a nanocrystal immersed in pure water, and (4) a nanocrystal immersed in an ionic solution. In some cases, the equilibration of the system can take several microseconds. The results from this work showed that the solubility of NaCl was the same, within simulation error, for the four setups, and in agreement with previously reported values from simulations with the setup (1). The system of a nanocrystal immersed in supersaturated solution was found to equilibrate faster than others. In agreement with laser-Doppler droplet measurements, at equilibrium with the solution the crystals in all the setups had a slight positive charge.

The Impact of Rechargeable Batteries: Quantifying the Cost and Weight for a Marine Infantry Battalion

DTIC Science & Technology

2011-12-01

Suitcase Portable Charger (SPC), Vehicle - Mounted Charger (VMC), Solar Portable Power System (SPACES) 15. NUMBER OF PAGES 77 16. PRICE CODE 17...battery (MCCOC, 2010): the Soldier Portable Charger (SPC), the Vehicle Mounted Charger (VMC), and the Solar Portable Alternative Communication Energy...Suitcase Portable Charger TO&E Table of Organization and Equipment UHF Ultra High Frequency VHF Very High Frequency VMC Vehicle Mounted

Mitigating an increase of specific power consumption in a cryogenic air separation unit at reduced oxygen production

NASA Astrophysics Data System (ADS)

Singla, Rohit; Chowdhury, Kanchan

2017-02-01

Specific power consumed in a Linde double column air separation unit (ASU) increases as the quantity of oxygen produced at a given purity is decreased due to the changes of system requirement or market demand. As the plant operates in part load condition, the specific power consumption (SPC) increases as the total power consumption remains the same. In order to mitigate the increase of SPC at lower oxygen production, the operating pressure of high pressure column (HPC) can be lowered by extending the low pressure column (LPC) by a few trays and adding a second reboiler. As the duty of second reboiler in LPC is increased, the recovery of oxygen decreases with a lowering of the HPC pressure. This results in mitigation of the increase of SPC of the plant. A Medium pressure ASU with dual reboiler that produces pressurised gaseous and liquid products of oxygen and nitrogen is simulated in Aspen Hysys 8.6®, a commercial process simulator to determine SPC at varying oxygen production. The effects of reduced pressure of air feed into the cold box on the size of heat exchangers (HX) are analysed. Operation strategy to obtain various oxygen production rates at varying demand is also proposed.

Review of the patient positioning reproducibility in head-and-neck radiotherapy using Statistical Process Control.

PubMed

Moore, Sarah J; Herst, Patries M; Louwe, Robert J W

2018-05-01

A remarkable improvement in patient positioning was observed after the implementation of various process changes aiming to increase the consistency of patient positioning throughout the radiotherapy treatment chain. However, no tool was available to describe these changes over time in a standardised way. This study reports on the feasibility of Statistical Process Control (SPC) to highlight changes in patient positioning accuracy and facilitate correlation of these changes with the underlying process changes. Metrics were designed to quantify the systematic and random patient deformation as input for the SPC charts. These metrics were based on data obtained from multiple local ROI matches for 191 patients who were treated for head-and-neck cancer during the period 2011-2016. SPC highlighted a significant improvement in patient positioning that coincided with multiple intentional process changes. The observed improvements could be described as a combination of a reduction in outliers and a systematic improvement in the patient positioning accuracy of all patients. SPC is able to track changes in the reproducibility of patient positioning in head-and-neck radiation oncology, and distinguish between systematic and random process changes. Identification of process changes underlying these trends requires additional statistical analysis and seems only possible when the changes do not overlap in time. Copyright © 2018 Elsevier B.V. All rights reserved.

Comparison of bulk-tank standard plate count and somatic cell count for Wisconsin dairy farms in three size categories.

PubMed

Ingham, S C; Hu, Y; Ané, C

2011-08-01

The objective of this study was to evaluate possible claims by advocates of small-scale dairy farming that milk from smaller Wisconsin farms is of higher quality than milk from larger Wisconsin farms. Reported bulk tank standard plate count (SPC) and somatic cell count (SCC) test results for Wisconsin dairy farms were obtained for February to December, 2008. Farms were sorted into 3 size categories using available size-tracking criteria: small (≤118 cows; 12,866 farms), large (119-713 cattle; 1,565 farms), and confined animal feeding operations (≥714 cattle; 160 farms). Group means were calculated (group=farm size category) for the farms' minimum, median, mean, 90th percentile, and maximum SPC and SCC. Statistical analysis showed that group means for median, mean, 90th percentile, and maximum SPC and SCC were almost always significantly higher for the small farm category than for the large farm and confined animal feeding operations farm categories. With SPC and SCC as quality criteria and the 3 farm size categories of ≤118, 119 to 713, and ≥714 cattle, the claim of Wisconsin smaller farms producing higher quality milk than Wisconsin larger farms cannot be supported. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Mediator effect of statistical process control between Total Quality Management (TQM) and business performance in Malaysian Automotive Industry

NASA Astrophysics Data System (ADS)

Ahmad, M. F.; Rasi, R. Z.; Zakuan, N.; Hisyamudin, M. N. N.

2015-12-01

In today's highly competitive market, Total Quality Management (TQM) is vital management tool in ensuring a company can success in their business. In order to survive in the global market with intense competition amongst regions and enterprises, the adoption of tools and techniques are essential in improving business performance. There are consistent results between TQM and business performance. However, only few previous studies have examined the mediator effect namely statistical process control (SPC) between TQM and business performance. A mediator is a third variable that changes the association between an independent variable and an outcome variable. This study present research proposed a TQM performance model with mediator effect of SPC with structural equation modelling, which is a more comprehensive model for developing countries, specifically for Malaysia. A questionnaire was prepared and sent to 1500 companies from automotive industry and the related vendors in Malaysia, giving a 21.8 per cent rate. Attempts were made at findings significant impact of mediator between TQM practices and business performance showed that SPC is important tools and techniques in TQM implementation. The result concludes that SPC is partial correlation between and TQM and BP with indirect effect (IE) is 0.25 which can be categorised as high moderator effect.

Formation of porous crystals via viscoelastic phase separation

NASA Astrophysics Data System (ADS)

Tsurusawa, Hideyo; Russo, John; Leocmach, Mathieu; Tanaka, Hajime

2017-10-01

Viscoelastic phase separation of colloidal suspensions can be interrupted to form gels either by glass transition or by crystallization. With a new confocal microscopy protocol, we follow the entire kinetics of phase separation, from homogeneous phase to different arrested states. For the first time in experiments, our results unveil a novel crystallization pathway to sponge-like porous crystal structures. In the early stages, we show that nucleation requires a structural reorganization of the liquid phase, called stress-driven ageing. Once nucleation starts, we observe that crystallization follows three different routes: direct crystallization of the liquid phase, the Bergeron process, and Ostwald ripening. Nucleation starts inside the reorganized network, but crystals grow past it by direct condensation of the gas phase on their surface, driving liquid evaporation, and producing a network structure different from the original phase separation pattern. We argue that similar crystal-gel states can be formed in monatomic and molecular systems if the liquid phase is slow enough to induce viscoelastic phase separation, but fast enough to prevent immediate vitrification. This provides a novel pathway to form nanoporous crystals of metals and semiconductors without dealloying, which may be important for catalytic, optical, sensing, and filtration applications.

Solubility of KF and NaCl in water by molecular simulation.

PubMed

Sanz, E; Vega, C

2007-01-07

The solubility of two ionic salts, namely, KF and NaCl, in water has been calculated by Monte Carlo molecular simulation. Water has been modeled with the extended simple point charge model (SPC/E), ions with the Tosi-Fumi model and the interaction between water and ions with the Smith-Dang model. The chemical potential of the solute in the solution has been computed as the derivative of the total free energy with respect to the number of solute particles. The chemical potential of the solute in the solid phase has been calculated by thermodynamic integration to an Einstein crystal. The solubility of the salt has been calculated as the concentration at which the chemical potential of the salt in the solution becomes identical to that of the pure solid. The methodology used in this work has been tested by reproducing the results for the solubility of KF determined previously by Ferrario et al. [J. Chem. Phys. 117, 4947 (2002)]. For KF, it was found that the solubility of the model is only in qualitative agreement with experiment. The variation of the solubility with temperature for KF has also been studied. For NaCl, the potential model used predicts a solubility in good agreement with the experimental value. The same is true for the hydration chemical potential at infinite dilution. Given the practical importance of solutions of NaCl in water the model used in this work, whereas simple, can be of interest for future studies.

Effects of gramicidin-A on the adsorption of phospholipids to the air–water interface

PubMed Central

Biswas, Samares C.; Rananavare, Shankar B.; Hall, Stephen B.

2012-01-01

Prior studies suggest that the hydrophobic surfactant proteins, SP-B and SP-C, promote adsorption of the lipids in pulmonary surfactant to an air–water interface by stabilizing a negatively curved rate-limiting structure that is intermediate between bilayer vesicles and the surface film. This model predicts that other peptides capable of stabilizing negative curvature should also promote lipid adsorption. Previous reports have shown that under appropriate conditions, gramicidin-A (GrA) induces dioleoyl phosphatidylcholine (DOPC), but not dimyristoyl phosphatidylcholine (DMPC), to form the negatively curved hexagonal-II (HII) phase. The studies reported here determined if GrA would produce the same effects on adsorption of DMPC and DOPC that the hydrophobic surfactant proteins have on the surfactant lipids. Small angle X-ray scattering and 31P-nuclear magnetic resonance confirmed that at the particular conditions used to study adsorption, GrA induced DOPC to form the HII phase, but DMPC remained lamellar. Measurements of surface tension showed that GrA in vesicles produced a general increase in the rate of adsorption for both phospholipids. When restricted to the interface, however, in preexisting films, GrA with DOPC, but not with DMPC, replicated the ability of the surfactant proteins to promote adsorption of vesicles containing only the lipids. The correlation between the structural and functional effects of GrA with the two phospholipids, and the similar effects on adsorption of GrA with DOPC and the hydrophobic surfactant proteins with the surfactant lipids fit with the model in which SP-B and SP-C facilitate adsorption by stabilizing a rate-limiting intermediate with negative curvature. PMID:16242116

Enhanced degradation of benzene by percarbonate activated with Fe(II)-glutamate complex.

PubMed

Fu, Xiaori; Gu, Xiaogang; Lu, Shuguang; Miao, Zhouwei; Xu, Minhui; Zhang, Xiang; Danish, Muhammad; Cui, Hang; Farooq, Usman; Qiu, Zhaofu; Sui, Qian

2016-04-01

Effective degradation of benzene was achieved in sodium percarbonate (SPC)/Fe(II)-Glu system. The presence of glutamate (Glu) could enhance the regeneration of Fe(III) to Fe(II), which ensures the benzene degradation efficiency at wider pH range and eliminate the influence of HCO3 (-) in low concentration. Meanwhile, the significant scavenging effects of high HCO3 (-) concentration could also be overcome by increasing the Glu/SPC/Fe(II)/benzene molar ratio. Free radical probe compound tests, free radical scavenger tests, and electron paramagnetic resonance (EPR) analysis were conducted to explore the reaction mechanism for benzene degradation, in which hydroxyl radical (HO•) and superoxide anion radical (O2 (•-)) were confirmed as the predominant species responsible for benzene degradation. In addition, the results obtained in actual groundwater test strongly indicated that SPC/Fe(II)-Glu system is applicable for the remediation of benzene-contaminated groundwater in practice.

Update on voiding dysfunction managed with suprapubic catheterization

PubMed Central

2017-01-01

As the population ages the prevalence of long-term urinary catheters, especially in the elderly, is going to increase. Urinary catheters are usually placed to manage urinary retention or incontinence that cannot be managed any other way. There is significant morbidity associated with an indwelling catheter. The commonest problems are catheter blockages, infection and bladder stones. These will occur with a similar incidence with either a suprapubic or a urethral catheter. Urethral complications such as strictures, scrotal infection and erosion are less common with suprapubic catheterization (SPC). However the benefit of having a SPC needs to be balanced against the risks involved in inserting the catheter suprapubically. Patient reported symptoms show that a SPC is more comfortable and better tolerated than a urethral catheter. However there needs to be more research into developing better catheters that reduce the frequency of urinary infections and blockages and hence catheter morbidity. PMID:28791237

An efficient approach for cloning the dNDP-glucose synthase gene from actinomycetes and its application in Streptomyces spectabilis, a spectinomycin producer.

PubMed

Hyun, C; Kim, S S; Sohng, J K; Hahn, J; Kim, J; Suh, J

2000-02-01

Specifically designed PCR primers were applied to amplify a segment of dTDP-glucose synthase gene from six actinomycete strains. About 300-bp or 580-bp DNA fragments were obtained from all the organisms tested. By DNA sequence analysis, seven amplified fragments showed high homology with dTDP-glucose synthase genes that participate in the biosynthesis of secondary metabolites or in deoxy-sugar moieties in lipopolysaccharides. In addition, we have cloned a 45-kb region of DNA from Streptomyces spectabilis ATCC27741, a spectinomycin producer which contained the dTDP-glucose synthase and dTDP-glucose 4,6-dehydratase genes named spcD and spcE, respectively. The spcE gene was expressed in Escherichia coli and the activity was assayed in cell extracts. The enzyme showed substrate specificity only to dTDP-glucose.

Supra-pubic versus urethral catheter after robot-assisted radical prostatectomy: systematic review of current evidence.

PubMed

Bertolo, Riccardo; Tracey, Andrew; Dasgupta, Prokar; Rocco, Bernardo; Micali, Salvatore; Bianchi, Giampaolo; Hampton, Lance; Tewari, Ash K; Porpiglia, Francesco; Autorino, Riccardo

2018-03-29

To provide latest evidence on the use of suprapubic catheter (SPC) versus urethral catheter (UC) after robot-assisted laparoscopic radical prostatectomy (RARP). A systematic revision of literature was performed up to September 2017 using different search engines (Pubmed, Ovid, Scopus) to identified studies comparing the use of SPC versus standard UC after RARP. Identification and selection of the studies were conducted according to the preferred reporting items for systematic reviews and meta-analysis criteria. For continuous outcomes, the weighted mean difference (WMD) was used as a summary measure, whereas the odds ratio (OR) or risk ratio (RR) with 95% confidence interval (CI) was calculated for binary variables. RR was preferred in cases of a high number of events to avoid overestimation. Pooled estimates were calculated using the random-effect model to account for clinical heterogeneity. All statistical analyses were performed using Review manager 5 (Cochrane Collaboration, Oxford, UK). Eight studies were identified and included in this systematic review, namely 3 RCTs, 4 non-randomized prospective studies, and one retrospective study. A total of 966 RARP cases were collected for the cumulative analysis. Among them, 492 patients received standard UC and 474 SPC placement after RARP. UC patients had higher baseline PSA (WMD 0.44 ng/ml; p = 0.02). Visual Analog Scale (VAS) score was found to be significantly lower in patients with SPC at postoperative day 7 (WMD 0.53; 95% CI 0.13-0.93; p = 0.009). Regarding penile pain, a significant difference in favor of the SPC group was found at postoperative day 7 assessment (WMD 1.2; 95% CI 0.82-1.6; p < 0.001). More patients in the SPC group reported "not at all" or "minimal pain" at this time point (OR 0.17, 95% CI 0.06, 0.44; p < 0.001). No significant differences were found in terms of continence recovery rate at 6-12 weeks between the groups (UC 78.7%, 88.2%; RR 0.92, 95% CI 0.84, 1.01; p = 0.09). Similarly, no differences were found in terms of catheter-related issues (p = 0.17). However, UC patients had lower likelihood of overall complications (OR 0.44, 95% CI 0.21-0.89, p = 0.02). Available evidence suggests that the use of SPC can be a viable option for postoperative urine drainage after RARP, as it can translate into decreased postoperative pain without carrying a significant higher risk of catheter-related complications. Further investigation seems to be warranted, ideally within the framework of a multicentre randomized study with standardized analysis of outcomes.

Phase separations in mixtures of a liquid crystal and a nanocolloidal particle.

PubMed

Matsuyama, Akihiko

2009-11-28

We present a mean field theory to describe phase separations in mixtures of a liquid crystal and a nanocolloidal particle. By taking into account a nematic, a smectic A ordering of the liquid crystal, and a crystalline ordering of the nanoparticle, we calculate the phase diagrams on the temperature-concentration plane. We predict various phase separations, such as a smectic A-crystal phase separation and a smectic A-isotropic-crystal triple point, etc., depending on the interactions between the liquid crystal and the colloidal surface. Inside binodal curves, we find new unstable and metastable regions, which are important in the phase ordering dynamics. We also find a crystalline ordering of the nanoparticles dispersed in a smectic A phase and a nematic phase. The cooperative phenomena between liquid-crystalline ordering and crystalline ordering induce a variety of phase diagrams.

Skeletal dosimetry based on µCT images of trabecular bone: update and comparisons

NASA Astrophysics Data System (ADS)

Kramer, R.; Cassola, V. F.; Vieira, J. W.; Khoury, H. J.; de Oliveira Lira, C. A. B.; Robson Brown, K.

2012-06-01

Two skeletal dosimetry methods using µCT images of human bone have recently been developed: the paired-image radiation transport (PIRT) model introduced by researchers at the University of Florida (UF) in the US and the systematic-periodic cluster (SPC) method developed by researchers at the Federal University of Pernambuco in Brazil. Both methods use µCT images of trabecular bone (TB) to model spongiosa regions of human bones containing marrow cavities segmented into soft tissue volumes of active marrow (AM), trabecular inactive marrow and the bone endosteum (BE), which is a 50 µm thick layer of marrow on all TB surfaces and on cortical bone surfaces next to TB as well as inside the medullary cavities. With respect to the radiation absorbed dose, the AM and the BE are sensitive soft tissues for the induction of leukaemia and bone cancer, respectively. The two methods differ mainly with respect to the number of bone sites and the size of the µCT images used in Monte Carlo calculations and they apply different methods to simulate exposure from radiation sources located outside the skeleton. The PIRT method calculates dosimetric quantities in isolated human bones while the SPC method uses human bones embedded in the body of a phantom which contains all relevant organs and soft tissues. Consequently, the SPC method calculates absorbed dose to the AM and to the BE from particles emitted by radionuclides concentrated in organs or from radiation sources located outside the human body in one calculation step. In order to allow for similar calculations of AM and BE absorbed doses using the PIRT method, the so-called dose response functions (DRFs) have been developed based on absorbed fractions (AFs) of energy for electrons isotropically emitted in skeletal tissues. The DRFs can be used to transform the photon fluence in homogeneous spongiosa regions into absorbed dose to AM and BE. This paper will compare AM and BE AFs of energy from electrons emitted in skeletal tissues calculated with the SPC and the PIRT method and AM and BE absorbed doses and AFs calculated with PIRT-based DRFs and with the SPC method. The results calculated with the two skeletal dosimetry methods agree well if one takes the differences between the two models properly into account. Additionally, the SPC method will be updated with larger µCT images of TB.

Phase transformations during the growth of paracetamol crystals from the vapor phase

NASA Astrophysics Data System (ADS)

Belyaev, A. P.; Rubets, V. P.; Antipov, V. V.; Bordei, N. S.

2014-07-01

Phase transformations during the growth of paracetamol crystals from the vapor phase are studied by differential scanning calorimetry. It is found that the vapor-crystal phase transition is actually a superposition of two phase transitions: a first-order phase transition with variable density and a second-order phase transition with variable ordering. The latter, being a diffuse phase transition, results in the formation of a new, "pretransition," phase irreversibly spent in the course of the transition, which ends in the appearance of orthorhombic crystals. X-ray diffraction data and micrograph are presented.

Use of a case-mix approach to study the trends in the incidence of second primary cancers.

PubMed

Gass, Boris; Marrer, Emilie; Bara, Simona; Ligier, Karine; Molinié, Florence; Colonna, Marc; Daubisse-Marliac, Laetitia; Trétarre, Brigitte; Lapôtre-Ledoux, Bénédicte; Woronoff, Anne-Sophie; Guizard, Anne-Valérie; Bouvier, Véronique; Troussard, Xavier; Gaiddon, Christian; Klein, Delphine; Velten, Michel; Jégu, Jérémie

2018-05-01

To analyze trends in second primary cancer (SPC) incidence by using a case-mix approach to standardize on first cancer site distribution. Cases registered by 13 French cancer registries between 1989 and 2010 and followed-up until June 2013 were included. The person-year approach was used to compute standardized incidence ratios (SIRs) of metachronous SPC. Usual SIRs and cancer site-specific weighted SIRs called "case-mix SIRs" (cmSIRs) were estimated by sex and calendar period of first cancer diagnosis. Calendar trends in SIRs and cmSIRs were compared. More than 2.9 million person-years at risk were included. Among males, SIRs dropped from 1.49 to 1.23 between 1989-1994 and 2005-2010, while cmSIRs decreased from 1.40 to 1.27. This difference seems mainly related to a stronger representation of prostate cancers (at lower risk of SPC) and a weaker contribution of bladder and head and neck cancers (at higher risk of SPC) in recent periods of diagnosis. Among females, both SIRs and cmSIRs have remained stable at around 1.22 and 1.21, respectively. The cmSIR is an indicator that is not influenced by changes in first cancer site distribution. Its use should be encouraged to assess second cancer incidence control. Copyright © 2018 Elsevier Inc. All rights reserved.

Genome-wide haploinsufficiency screen reveals a novel role for γ-TuSC in spindle organization and genome stability

PubMed Central

Choy, John S.; O'Toole, Eileen; Schuster, Breanna M.; Crisp, Matthew J.; Karpova, Tatiana S.; McNally, James G.; Winey, Mark; Gardner, Melissa K.; Basrai, Munira A.

2013-01-01

How subunit dosage contributes to the assembly and function of multimeric complexes is an important question with implications in understanding biochemical, evolutionary, and disease mechanisms. Toward identifying pathways that are susceptible to decreased gene dosage, we performed a genome-wide screen for haploinsufficient (HI) genes that guard against genome instability in Saccharomyces cerevisiae. This led to the identification of all three genes (SPC97, SPC98, and TUB4) encoding the evolutionarily conserved γ-tubulin small complex (γ-TuSC), which nucleates microtubule assembly. We found that hemizygous γ-TuSC mutants exhibit higher rates of chromosome loss and increases in anaphase spindle length and elongation velocities. Fluorescence microscopy, fluorescence recovery after photobleaching, electron tomography, and model convolution simulation of spc98/+ mutants revealed improper regulation of interpolar (iMT) and kinetochore (kMT) microtubules in anaphase. The underlying cause is likely due to reduced levels of Tub4, as overexpression of TUB4 suppressed the spindle and chromosome segregation defects in spc98/+ mutants. We propose that γ-TuSC is crucial for balanced assembly between iMTs and kMTs for spindle organization and accurate chromosome segregation. Taken together, the results show how gene dosage studies provide critical insights into the assembly and function of multisubunit complexes that may not be revealed by using traditional studies with haploid gene deletion or conditional alleles. PMID:23825022

Genome-wide haploinsufficiency screen reveals a novel role for γ-TuSC in spindle organization and genome stability.

PubMed

Choy, John S; O'Toole, Eileen; Schuster, Breanna M; Crisp, Matthew J; Karpova, Tatiana S; McNally, James G; Winey, Mark; Gardner, Melissa K; Basrai, Munira A

2013-09-01

How subunit dosage contributes to the assembly and function of multimeric complexes is an important question with implications in understanding biochemical, evolutionary, and disease mechanisms. Toward identifying pathways that are susceptible to decreased gene dosage, we performed a genome-wide screen for haploinsufficient (HI) genes that guard against genome instability in Saccharomyces cerevisiae. This led to the identification of all three genes (SPC97, SPC98, and TUB4) encoding the evolutionarily conserved γ-tubulin small complex (γ-TuSC), which nucleates microtubule assembly. We found that hemizygous γ-TuSC mutants exhibit higher rates of chromosome loss and increases in anaphase spindle length and elongation velocities. Fluorescence microscopy, fluorescence recovery after photobleaching, electron tomography, and model convolution simulation of spc98/+ mutants revealed improper regulation of interpolar (iMT) and kinetochore (kMT) microtubules in anaphase. The underlying cause is likely due to reduced levels of Tub4, as overexpression of TUB4 suppressed the spindle and chromosome segregation defects in spc98/+ mutants. We propose that γ-TuSC is crucial for balanced assembly between iMTs and kMTs for spindle organization and accurate chromosome segregation. Taken together, the results show how gene dosage studies provide critical insights into the assembly and function of multisubunit complexes that may not be revealed by using traditional studies with haploid gene deletion or conditional alleles.

Development of ipsilateral chest wall spindle cell carcinoma in a patient with invasive ductal breast carcinoma during postoperative adjuvant therapy: A case report.

PubMed

Li, Kaifu; Kang, Hua; Wang, Yajun; Hai, Tao; Wang, Bixiao

2018-05-01

Metaplastic breast carcinoma (MBC) is rare subtype of breast carcinoma and is regarded as ductal carcinoma that undergoes metaplasia into a glandular growth pattern. Spindle cell carcinoma (SPC) is a subtype of MBC with a predominant spindle cell component. The patient was a 52-year-old female with invasive ductal breast carcinoma who underwent a modified radical mastectomy and an axillary node dissection. A new lump was observed underneath the surgical site between the pectoralis major and pectoralis minor muscles 45 days after the patient underwent sequential postoperative chemotherapy and radiotherapy. It was speculated that the new lesion had developed during postoperative adjuvant therapy. And the new lesion was regarded as a recurrence. We performed a wide dissection of the tumor with negative margins. The pathology of the tumor indicated SPC. Then, the patient received chemotherapy and demonstrated a poor response. Local recurrence and pulmonary metastasis developed shortly afterwards, and the patient succumbed to the disease within 5 months. Local recurrence with metaplastic SPC transformed from invasive ductal breast carcinoma during postoperative chemotherapy and radiotherapy is rare. The failure of subsequent chemotherapy and the progression of disease indicate the aggressive nature of SPC and its decreased sensitivity to chemotherapy and radiotherapy. Further studies must be performed to improve the prognosis of these patients.

A Physical Model for Three-Phase Compaction in Silicic Magma Reservoirs

NASA Astrophysics Data System (ADS)

Huber, Christian; Parmigiani, Andrea

2018-04-01

We develop a model for phase separation in magma reservoirs containing a mixture of silicate melt, crystals, and fluids (exsolved volatiles). The interplay between the three phases controls the dynamics of phase separation and consequently the chemical and physical evolution of magma reservoirs. The model we propose is based on the two-phase damage theory approach of Bercovici et al. (2001, https://doi.org/10.1029/2000JB900430) and Bercovici and Ricard (2003, https://doi.org/10.1046/j.1365-246X.2003.01854.x) because it offers the leverage of considering interface (in the macroscopic limit) between phases that can deform depending on the mechanical work and phase changes taking place locally in the magma. Damage models also offer the advantage that pressure is defined uniquely to each phase and does not need to be equal among phases, which will enable us to consider, in future studies, the large capillary pressure at which fluids are mobilized in mature, crystal-rich, magma bodies. In this first analysis of three-phase compaction, we solve the three-phase compaction equations numerically for a simple 1-D problem where we focus on the effect of fluids on the efficiency of melt-crystal separation considering the competition between viscous and buoyancy stresses only. We contrast three sets of simulations to explore the behavior of three-phase compaction, a melt-crystal reference compaction scenario (two-phase compaction), a three-phase scenario without phase changes, and finally a three-phase scenario with a parameterized second boiling (crystallization-induced exsolution). The simulations show a dramatic difference between two-phase (melt crystals) and three-phase (melt-crystals-exsolved volatiles) compaction-driven phase separation. We find that the presence of a lighter, significantly less viscous fluid hinders melt-crystal separation.

Shear induced structures in crystallizing cocoa butter

NASA Astrophysics Data System (ADS)

Mazzanti, Gianfranco; Guthrie, Sarah E.; Sirota, Eric B.; Marangoni, Alejandro G.; Idziak, Stefan H. J.

2004-03-01

Cocoa butter is the main structural component of chocolate and many cosmetics. It crystallizes in several polymorphs, called phases I to VI. We used Synchrotron X-ray diffraction to study the effect of shear on its crystallization. A previously unreported phase (phase X) was found and a crystallization path through phase IV under shear was observed. Samples were crystallized under shear from the melt in temperature controlled Couette cells, at final crystallization temperatures of 17.5^oC, 20^oC and 22.5^oC in Beamline X10A of NSLS. The formation of phase X was observed at low shear rates (90 s-1) and low crystallization temperature (17.5^oC), but was absent at high shear (720 s-1) and high temperature (20^oC). The d-spacing and melting point suggest that this new phase is a mixture rich on two of the three major components of cocoa butter. We also found that, contrary to previous reports, the transition from phase II to phase V can happen through the intermediate phase IV, at high shear rates and temperature.

Using Statistical Process Control for detecting anomalies in multivariate spatiotemporal Earth Observations

NASA Astrophysics Data System (ADS)

Flach, Milan; Mahecha, Miguel; Gans, Fabian; Rodner, Erik; Bodesheim, Paul; Guanche-Garcia, Yanira; Brenning, Alexander; Denzler, Joachim; Reichstein, Markus

2016-04-01

The number of available Earth observations (EOs) is currently substantially increasing. Detecting anomalous patterns in these multivariate time series is an important step in identifying changes in the underlying dynamical system. Likewise, data quality issues might result in anomalous multivariate data constellations and have to be identified before corrupting subsequent analyses. In industrial application a common strategy is to monitor production chains with several sensors coupled to some statistical process control (SPC) algorithm. The basic idea is to raise an alarm when these sensor data depict some anomalous pattern according to the SPC, i.e. the production chain is considered 'out of control'. In fact, the industrial applications are conceptually similar to the on-line monitoring of EOs. However, algorithms used in the context of SPC or process monitoring are rarely considered for supervising multivariate spatio-temporal Earth observations. The objective of this study is to exploit the potential and transferability of SPC concepts to Earth system applications. We compare a range of different algorithms typically applied by SPC systems and evaluate their capability to detect e.g. known extreme events in land surface processes. Specifically two main issues are addressed: (1) identifying the most suitable combination of data pre-processing and detection algorithm for a specific type of event and (2) analyzing the limits of the individual approaches with respect to the magnitude, spatio-temporal size of the event as well as the data's signal to noise ratio. Extensive artificial data sets that represent the typical properties of Earth observations are used in this study. Our results show that the majority of the algorithms used can be considered for the detection of multivariate spatiotemporal events and directly transferred to real Earth observation data as currently assembled in different projects at the European scale, e.g. http://baci-h2020.eu/index.php/ and http://earthsystemdatacube.net/. Known anomalies such as the Russian heatwave are detected as well as anomalies which are not detectable with univariate methods.

Adsorption isotherms of water on mica: redistribution and film growth.

PubMed

Malani, Ateeque; Ayappa, K G

2009-01-29

Adsorption isotherms of water on muscovite mica are obtained using grand canonical Monte Carlo simulations over a wide range of relative vapor pressures, p/p(0) at 298 K. Three distinct stages are observed in the adsorption isotherm. A sharp rise in the water coverage occurs for 0 < p/p(0) < 0.1. This is followed by a relatively slow increase in the coverage for 0.1 < or = p/p(0) < or = 0.7. Above p/p(0) = 0.7, a second increase in the coverage occurs due to the adsorption of water with bulklike features. The derived film thickness and isotherm shape for the simple point charge (SPC) water model is in excellent agreement with recent experiments of Balmer et al. [ Langmuir 2008 , 24 , 1566 ]. A novel observation is the significant redistribution of water between adsorbed layers as the water film develops. This redistribution is most pronounced for 0.1 < or = p/p(0) < or = 0.7, where water is depleted from the inner layers and film growth is initiated on the outer layer. During this stage, potassium hydration is found to play a dominant role in the rearrangement of water near the mica surface. The analysis of structural features reveals a strongly bound first layer of water molecules occupying the ditrigonal cavities between the potassium ions. In-plane structure of oxygen in the second layer, which forms part of the first hydration shell of potassium, reveals a liquidlike structure with the oxygen-oxygen pair correlation function displaying features similar to bulk water. Isosteric heats of adsorption were found to be in good agreement with the differential microcalorimetric data of Rakhmatkariev ( Clays Clay Miner. 2006 , 54 , 402 ), over the entire range of pressures investigated. Both SPC and extended simple point charge (SPC/E) water models were found to yield qualitatively similar adsorption and structural characteristics, with the SPC/E model predicting lower coverages than the SPC model for p/p(0) > 0.7.

Using in-situ Glider Data to Improve the Interpretation of Time-Series Data in the San Pedro Channel

NASA Astrophysics Data System (ADS)

Teel, E.; Liu, X.; Seegers, B. N.; Ragan, M. A.; Jones, B. H.; Levine, N. M.

2016-02-01

Oceanic time-series have provided insight into biological, physical, and chemical processes and how these processes change over time. However, time-series data collected near coastal zones have not been used as broadly because of regional features that may prevent extrapolation of local results. Though these sites are inherently more affected by local processes, broadening the application of coastal data is crucial for improved modeling of processes such as total carbon drawdown and the development of oxygen minimum zones. Slocum gliders were deployed off the coast of Los Angeles from February to July of 2013 and 2014 providing high temporal and spatial resolution data of the San Pedro Channel (SPC), which includes the San Pedro Ocean Time Series (SPOT). The data were collapsed onto a standardized grid and primary and secondary characteristics of glider profiles were analyzed by principal component analysis to determine the processes impacting SPC and SPOT. The data fell into four categories: active upwelling, offshore intrusion, subsurface bloom, and surface bloom. Waters across the SPC were most similar to offshore water masses, even during the upwelling season when near-shore blooms are commonly observed. The SPOT site was found to be representative of the SPC 86% of the time, suggesting that the findings from SPOT are applicable for the entire SPC. Subsurface blooms were common in both years with co-located chlorophyll and particle maxima, and results suggested that these subsurface blooms contribute significantly to the local primary production. Satellite estimation of integrated chlorophyll was poor, possibly due to the prevalence of subsurface blooms and shallow optical depths during surface blooms. These results indicate that high resolution in-situ glider deployments can be used to determine the spatial domain of coastal time-series data, allowing for broader application of these datasets and greater integration into modeling efforts.

Acceleration performance of individual European sea bass Dicentrarchus labrax measured with a sprint performance chamber: comparison with high-speed cinematography and correlates with ecological performance.

PubMed

Vandamm, Joshua P; Marras, Stefano; Claireaux, Guy; Handelsman, Corey A; Nelson, Jay A

2012-01-01

Locomotor performance can influence the ecological and evolutionary success of a species. For fish, favorable outcomes of predator-prey encounters are often presumably due to robust acceleration ability. Although escape-response or "fast-start" studies utilizing high-speed cinematography are prevalent, little is known about the contribution of relative acceleration performance to ecological or evolutionary success in a species. This dearth of knowledge may be due to the time-consuming nature of analyzing film, which imposes a practical limit on sample sizes. Herein, we present a high-throughput potential alternative for measuring fish acceleration performance using a sprint performance chamber (SPC). The acceleration performance of a large number of juvenile European sea bass (Dicentrarchus labrax) from two populations was analyzed. Animals from both hatchery and natural ontogenies were assessed, and animals of known acceleration ability had their ecological performance measured in a mesocosm environment. Individuals from one population also had their acceleration performance assessed by both high-speed cinematography and an SPC. Acceleration performance measured in an SPC was lower than that measured by classical high-speed video techniques. However, short-term repeatability and interindividual variation of acceleration performance were similar between the two techniques, and the SPC recorded higher sprint swimming velocities. Wild fish were quicker to accelerate in an SPC and had significantly greater accelerations than all groups of hatchery-raised fish. Acceleration performance had no significant effect on ecological performance (as assessed through animal growth and survival in the mesocosms). However, it is worth noting that wild animals did survive predation in the mesocosm better than farmed ones. Moreover, the hatchery-originated fish that survived the mesocosm experiment, when no predators were present, displayed significantly increased acceleration performance during their 6 mo in the mesocosm; this performance was found to be inversely proportional to growth rate.

CO2 diffusion in champagne wines: a molecular dynamics study.

PubMed

Perret, Alexandre; Bonhommeau, David A; Liger-Belair, Gérard; Cours, Thibaud; Alijah, Alexander

2014-02-20

Although diffusion is considered as the main physical process responsible for the nucleation and growth of carbon dioxide bubbles in sparkling beverages, the role of each type of molecule in the diffusion process remains unclear. In the present study, we have used the TIP5P and SPC/E water models to perform force field molecular dynamics simulations of CO2 molecules in water and in a water/ethanol mixture respecting Champagne wine proportions. CO2 diffusion coefficients were computed by applying the generalized Fick's law for the determination of multicomponent diffusion coefficients, a law that simplifies to the standard Fick's law in the case of champagnes. The CO2 diffusion coefficients obtained in pure water and water/ethanol mixtures composed of TIP5P water molecules were always found to exceed the coefficients obtained in mixtures composed of SPC/E water molecules, a trend that was attributed to a larger propensity of SPC/E water molecules to form hydrogen bonds. Despite the fact that the SPC/E model is more accurate than the TIP5P model to compute water self-diffusion and CO2 diffusion in pure water, the diffusion coefficients of CO2 molecules in the water/ethanol mixture are in much better agreement with the experimental values of 1.4 - 1.5 × 10(-9) m(2)/s obtained for Champagne wines when the TIP5P model is employed. This difference was deemed to rely on the larger propensity of SPC/E water molecules to maintain the hydrogen-bonded network between water molecules and form new hydrogen bonds with ethanol, although statistical issues cannot be completely excluded. The remarkable agreement between the theoretical CO2 diffusion coefficients obtained within the TIP5P water/ethanol mixture and the experimental data specific to Champagne wines makes us infer that the diffusion coefficient in these emblematic hydroalcoholic sparkling beverages is expected to remain roughly constant whathever their proportions in sugars, glycerol, or peptides.

Remote Ischaemic Preconditioning and Sevoflurane Postconditioning Synergistically Protect Rats from Myocardial Injury Induced by Ischemia and Reperfusion Partly via Inhibition TLR4/MyD88/NF-κB Signaling Pathway.

PubMed

Zhang, Jiru; Zhang, Jing; Yu, Peng; Chen, Min; Peng, Qingfeng; Wang, Zhiqiang; Dong, Nan

2017-01-01

A combination sevoflurane postconditioning (SPC) and remote ischemic preconditioning (RIPC) is proved effective in an ex vivo rat heart perfusion model. However, the combined effect of those two interventions is not tested in rat myocardial ischemia/reperfusion (I/R) model, and the underlying mechanisms remain to be elucidated. This study aimed to investigate the effect in vivo using a rat myocardial I/R model and illuminate the related mechanisms. Forty male Sprague-Dawley rats were randomly divided into the following 5 groups: i) sham-operated control; ii) I/R; iii) I/R + RIPC; iv) I/R + SPC; v) I/R + RIPC + SPC. The hemodynamic parameters were recorded at the end of reperfusion. The histological changes including the infarct size were assessed using Triphenyltetrazolium chloride (TTC) staining and H&E staining. In addition, the circulating levels of cardiac enzymes (CK-MB, hs-cTnT, and cTnT) inflammatory cytokines (IL-6, IL-8, and TNF-α) were detected. The expression levels of apoptosis-related proteins (C-Caspase 3, PARP, Bax, and Bcl-2), proinflammatory factors (TLR4, HMGB-1, MyD88, and p65), and IKB-α were measured by Western blot analysis. Real-time PCR was performed to detect mRNA levels of the proinflammatory factors. Both SPC and RIPC significantly reduced the infarct size, cardiac enzyme release, inflammatory cytokine secretion, and proinflammatory factor expression, and increased IKB-α expression compared to I/R group. Furthermore, the combination of those two strategies had synergic infarct size limiting and anti-inflammatory effects. The finding of this study suggested that the combination of SPC and RIPC had a potentially cardioprotective effect through inhibiting TLR4/MyD88/NF-κB signaling. © 2017 The Author(s) Published by S. Karger AG, Basel.

Novel theranostic zinc phthalocyanine-phospholipid complex self-assembled nanoparticles for imaging-guided targeted photodynamic treatment with controllable ROS production and shape-assisted enhanced cellular uptake.

PubMed

Ma, Jinyuan; Li, Yang; Liu, Guihua; Li, Ai; Chen, Yilin; Zhou, Xinyi; Chen, Dengyue; Hou, Zhenqing; Zhu, Xuan

2018-02-01

The novel drug delivery system based on self-assembly of zinc phthalocyanine-soybean phosphatidylcholine (ZnPc-SPC) complex was developed by a co-solvent method followed by a nanoprecipitaion technique. DSPE-PEG-methotrexate (DSPE-PEG-MTX) was introduced on the surface of ZnPc-SPC self-assembled nanoparticles (ZS) to endow them with folate receptor-targeting property. NMR, XRD, FTIR, and UV-vis-NIR analysis demonstrated the weak molecular interaction between ZnPc and SPC. The ZS functionalized with DSPE-PEG-MTX (ZSPM) was successfully constructed with an average particle size of ∼170nm, a narrow size distribution, and could remain physiologically stable for at least 7days. In vitro cellular uptake and cytotoxicity studies demonstrated that ZSPM exhibited stronger cellular uptake efficacy and photodynamic cytotoxicity against HeLa and MCF-7 cells than ZS functionalized with DSPE-mPEG (ZSP) and free ZnPc. More importantly, ZSPM showed the enhanced accumulation effect at the tumor region compared with ZSP by the active-plus-passive targeting via enhanced permeability and retention (EPR) effect and folate receptor-mediated endocytosis. Furthermore, in vivo antitumor effect and histological analysis demonstrated the superior tumor growth inhibition effect of ZSPM. In addition, the needle-shape ZSP (ZSPN) exhibited better in vitro cellular uptake and in vivo tumor accumulation compared with ZSP due to the shape-assisted effect. Moreover, the interesting off-on switch effect of reactive oxygen species (ROS) production of ZnPc-SPC complex-based nanoparticles was discovered to achieve photodynamic treatment in a controllable way. These findings suggested that the ZnPc-SPC complex-based self-assembled nanoparticles could serve as a promising and effective formulation to achieve tumor-targeting fluorescence imaging and enhanced photodynamic treatment. Copyright © 2017. Published by Elsevier B.V.

Mob/oriT, a mobilizable site-specific recombination system for unmarked genetic manipulation in Bacillus thuringiensis and Bacillus cereus.

PubMed

Wang, Pengxia; Zhu, Yiguang; Zhang, Yuyang; Zhang, Chunyi; Xu, Jianyi; Deng, Yun; Peng, Donghai; Ruan, Lifang; Sun, Ming

2016-06-10

Bacillus thuringiensis and Bacillus cereus are two important species in B. cereus group. The intensive study of these strains at the molecular level and construction of genetically modified bacteria requires the development of efficient genetic tools. To insert genes into or delete genes from bacterial chromosomes, marker-less manipulation methods were employed. We present a novel genetic manipulation method for B. thuringiensis and B. cereus strains that does not leave selection markers. Our approach takes advantage of the relaxase Mob02281 encoded by plasmid pBMB0228 from Bacillus thuringiensis. In addition to its mobilization function, this Mob protein can mediate recombination between oriT sites. The Mob02281 mobilization module was associated with a spectinomycin-resistance gene to form a Mob-Spc cassette, which was flanked by the core 24-bp oriT sequences from pBMB0228. A strain in which the wild-type chromosome was replaced with the modified copy containing the Mob-Spc cassette at the target locus was obtained via homologous recombination. Thus, the spectinomycin-resistance gene can be used to screen for Mob-Spc cassette integration mutants. Recombination between the two oriT sequences mediated by Mob02281, encoded by the Mob-Spc cassette, resulted in the excision of the Mob-Spc cassette, producing the desired chromosomal alteration without introducing unwanted selection markers. We used this system to generate an in-frame deletion of a target gene in B. thuringiensis as well as a gene located in an operon of B. cereus. Moreover, we demonstrated that this system can be used to introduce a single gene or an expression cassette of interest in B. thuringiensis. The Mob/oriT recombination system provides an efficient method for unmarked genetic manipulation and for constructing genetically modified bacteria of B. thuringiensis and B. cereus. Our method extends the available genetic tools for B. thuringiensis and B. cereus strains.

Tunable photonic crystals with partial bandgaps from blue phase colloidal crystals and dielectric-doped blue phases.

PubMed

Stimulak, Mitja; Ravnik, Miha

2014-09-07

Blue phase colloidal crystals and dielectric nanoparticle/polymer doped blue phases are demonstrated to combine multiple components with different symmetries in one photonic material, creating a photonic crystal with variable and micro-controllable photonic band structure. In this composite photonic material, one contribution to the band structure is determined by the 3D periodic birefringent orientational profile of the blue phases, whereas the second contribution emerges from the regular array of the colloidal particles or from the dielectric/nanoparticle-doped defect network. Using the planewave expansion method, optical photonic bands of the blue phase I and II colloidal crystals and related nanoparticle/polymer doped blue phases are calculated, and then compared to blue phases with no particles and to face-centred-cubic and body-centred-cubic colloidal crystals in isotropic background. We find opening of local band gaps at particular points of Brillouin zone for blue phase colloidal crystals, where there were none in blue phases without particles or dopants. Particle size and filling fraction of the blue phase defect network are demonstrated as parameters that can directly tune the optical bands and local band gaps. In the blue phase I colloidal crystal with an additionally doped defect network, interestingly, we find an indirect total band gap (with the exception of one point) at the entire edge of SC irreducible zone. Finally, this work demonstrates the role of combining multiple - by symmetry - differently organised components in one photonic crystal material, which offers a novel approach towards tunable soft matter photonic materials.

Expression of mutant Sftpcin murine alveolar epithelia drives spontaneous lung fibrosis.

PubMed

Nureki, Shin-Ichi; Tomer, Yaniv; Venosa, Alessandro; Katzen, Jeremy; Russo, Scott J; Jamil, Sarita; Barrett, Matthew; Nguyen, Vivian; Kopp, Meghan; Mulugeta, Surafel; Beers, Michael F

2018-06-19

Epithelial cell dysfunction is postulated as an important component in the pathogenesis of Idiopathic Pulmonary Fibrosis (IPF). Mutations in the Surfactant Protein C [SP-C] gene [SFTPC], an alveolar type 2 (AT2) cell restricted protein, have been found in sporadic and familial IPF. To causally link these events, we developed a knock-in mouse model capable of regulated expression of an IPF-associated Isoleucine to Threonine substitution at codon 73 [I73T] in Sftpc (SP-CI73T). Tamoxifen treated SP-CI73T cohorts developed rapid increases in SftpcI73T mRNA and misprocessed proSP-CI73T protein accompanied by increased early mortality (days 7-14). This acute phase was marked by diffuse parenchymal lung injury, tissue infiltration by monocytes, polycellular alveolitis, and elevations in bronchoalveolar lavage and AT2 mRNA contents of select inflammatory cytokines. Resolution of alveolitis (2-4 weeks), commensurate with a rise in TGFB1, was followed by aberrant remodeling marked by collagen deposition, AT2 cell hyperplasia, a-SMA positive cells, and restrictive lung physiology. The translational relevance of the model was supported by detection of multiple IPF biomarkers previously reported in human cohorts. These data provide proof of principle that mutant SP-C expression in vivo causes spontaneous lung fibrosis strengthening the role of AT2 dysfunction as a key upstream driver of IPF pathogenesis.

Control of the orientation and photoinduced phase transitions of macrocyclic azobenzene.

PubMed

Uchida, Emi; Sakaki, Kouji; Nakamura, Yumiko; Azumi, Reiko; Hirai, Yuki; Akiyama, Haruhisa; Yoshida, Masaru; Norikane, Yasuo

2013-12-16

Photoinduced phase transitions caused by photochromic reactions bring about a change in the state of matter at constant temperature. Herein, we report the photoinduced phase transitions of crystals of a photoresponsive macrocyclic compound bearing two azobenzene groups (1) at room temperature on irradiation with UV (365 nm) and visible (436 nm) light. The trans/trans isomer undergoes photoinduced phase transitions (crystal-isotropic phase-crystal) on UV light irradiation. The photochemically generated crystal exhibited reversible phase transitions between the crystal and the mesophase on UV and visible light irradiation. The molecular order of the randomly oriented crystals could be increased by irradiating with linearly polarized visible light, and the value of the order parameter was determined to be -0.84. Heating enhances the thermal cis-to-trans isomerization and subsequent cooling returned crystals of the trans/trans isomer. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Responses to Nitroprusside Following Hemorrhage in Anesthetized Pigs

DTIC Science & Technology

1991-08-01

well as SPC Bharatkumar Gandhi and SPC Johnny Singson. We also thank Mary Thomas for her secretarial assistance and Charles E. Wade, Ph.D., for his...anesthesia and operation in the head-up position. Anesth Analg 1977; 56:391-394. 9. Larsen R, Teichmann J, Hilfiker 0, Busse C, Sonntag H. Nitroprusside...JN, Burke LP. Nitroprusside. Ann Intern Med 1979; 91:752-757. O’Benar et al .-- Page 26 OFFICIAI. DISTRIBUTION I.IST (’o mmander US Army Medical

Single-Cycle Terahertz Pulse Generation from OH1 Crystal via Cherenkov Phase Matching

NASA Astrophysics Data System (ADS)

Uchida, Hirohisa; Oota, Kengo; Okimura, Koutarou; Kawase, Kodo; Takeya, Kei

2018-06-01

OH1 crystal is an organic nonlinear optical crystal with a large nonlinear optical constant. However, it has dispersion of refractive indices in the terahertz (THz) frequency. This limits the frequencies that satisfy the phase matching conditions for THz wave generation. In this study, we addressed the phase matching conditions for THz wave generation by combining an OH1 crystal with prism-coupled Cherenkov phase matching. We observed the generation of single-cycle THz pulses with a spectrum covering a frequency range of 3 THz. These results prove that combining prism-coupled Cherenkov phase matching with nonlinear optical crystals yields a THz wave generation method that is insusceptible to crystal dispersion.

Single-Cycle Terahertz Pulse Generation from OH1 Crystal via Cherenkov Phase Matching

NASA Astrophysics Data System (ADS)

Uchida, Hirohisa; Oota, Kengo; Okimura, Koutarou; Kawase, Kodo; Takeya, Kei

2018-03-01

OH1 crystal is an organic nonlinear optical crystal with a large nonlinear optical constant. However, it has dispersion of refractive indices in the terahertz (THz) frequency. This limits the frequencies that satisfy the phase matching conditions for THz wave generation. In this study, we addressed the phase matching conditions for THz wave generation by combining an OH1 crystal with prism-coupled Cherenkov phase matching. We observed the generation of single-cycle THz pulses with a spectrum covering a frequency range of 3 THz. These results prove that combining prism-coupled Cherenkov phase matching with nonlinear optical crystals yields a THz wave generation method that is insusceptible to crystal dispersion.

Temperature-insensitive phase-matched optical harmonic conversion crystal

DOEpatents

Barker, Charles E.; Eimerl, David; Velsko, Stephan P.; Roberts, David

1993-01-01

Temperature-insensitive, phase-matched harmomic frequency conversion of laser light at a preferred wavelength of 1.064 microns can be achieved by use of a crystal of deuterated l-arginine phosphate. The crystal is cut and oriented so that the laser light propagates inside the crystal along one of several required directions, which correspond to a temperature-insensitive, phase-matching locus. The method of measuring and calculating the temperature-insensitive, phase-matching angles can be extended to other fundamental wavelengths and other crystal compositions.

Temperature-insensitive phase-matched optical harmonic conversion crystal

DOEpatents

Barker, C.E.; Eimerl, D.; Velsko, S.P.; Roberts, D.

1993-11-23

Temperature-insensitive, phase-matched harmonic frequency conversion of laser light at a preferred wavelength of 1.064 microns can be achieved by use of a crystal of deuterated l-arginine phosphate. The crystal is cut and oriented so that the laser light propagates inside the crystal along one of several required directions, which correspond to a temperature-insensitive, phase-matching locus. The method of measuring and calculating the temperature-insensitive, phase-matching angles can be extended to other fundamental wavelengths and other crystal compositions. 12 figures.

Tenacious self-reliance in health maintenance may jeopardize late life survival.

PubMed

Hamm, Jeremy M; Chipperfield, Judith G; Perry, Raymond P; Parker, Patti C; Heckhausen, Jutta

2017-11-01

Although an active pursuit of health goals is typically adaptive, there may be circumstances in very late life when it is not. Our 10-year study of community-dwelling individuals (n = 220, 79-98 years-old) examined whether investing substantial effort into personal health (high selective primary control) in the absence of help-seeking strategies (low compensatory primary control) jeopardized survival for very old adults who varied in functional independence (low, high). Cox proportional hazard models showed selective primary control (SPC) predicted 10-year mortality risk for only those with low compensatory primary control (CPC) and high initial functional independence. For these individuals, each standard deviation increase in SPC predicted a 101% higher risk of death. Results are consistent with the lines-of-defense model (Heckhausen et al., 2013) and suggest that, for very old adults with little previous need for help-seeking strategies, tenacious self-reliance (high SPC, low CPC) may have life-shortening consequences. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Application of statistical process control to qualitative molecular diagnostic assays.

PubMed

O'Brien, Cathal P; Finn, Stephen P

2014-01-01

Modern pathology laboratories and in particular high throughput laboratories such as clinical chemistry have developed a reliable system for statistical process control (SPC). Such a system is absent from the majority of molecular laboratories and where present is confined to quantitative assays. As the inability to apply SPC to an assay is an obvious disadvantage this study aimed to solve this problem by using a frequency estimate coupled with a confidence interval calculation to detect deviations from an expected mutation frequency. The results of this study demonstrate the strengths and weaknesses of this approach and highlight minimum sample number requirements. Notably, assays with low mutation frequencies and detection of small deviations from an expected value require greater sample numbers to mitigate a protracted time to detection. Modeled laboratory data was also used to highlight how this approach might be applied in a routine molecular laboratory. This article is the first to describe the application of SPC to qualitative laboratory data.

Transient increase in the levels of gamma-tubulin complex in reorientation of cortical microtubules by gravity in azuki bean epicotyls

NASA Astrophysics Data System (ADS)

Soga, Kouichi; Kotake, Toshihisa; Wakabayashi, Kazuyuki; Kamisaka, Seiichiro; Hoson, Takayuki

Azuki bean (Vigna angularis Ohwi et Ohashi) seedlings were exposed to centrifugal hypergravity, and the changes in the orientation of cortical microtubules and the expression of genes cording γ-tubulin complex (VaTUBG and VaSpc98p) were examined. By 300 g treatment, the percentage of cells with transverse microtubules was decreased, while that with longitudinal microtubules was increased in epicotyls. Hypergravity increased the expression of VaTUBG and VaSpc98p transiently. Also, the expression of both genes was increased transiently by removal of hypergravity stimulus. Lanthanum and gadolinium ions, potential blockers of mechanosensitive calcium ion-permeable channels (mechanoreceptors), nullified reorientation of microtubules as well as up-regulation of expression of VaTUBG and VaSpc98p by hypergravity. These results suggest that mechanoreceptors on the plasma membrane may perceive the gravity signal, which leads to reorientation of cortical microtubules by transiently stimulating the formation of γ-tubulin complex.

Inspection system qualification and integration into the mask manufacturing environment

NASA Astrophysics Data System (ADS)

LaVoy, Rosanne; Fujioka, Ron

1995-12-01

Integration of a mask inspection system into a manufacturing environment poses new challenges to both the inspection engineer and the equipment supplier. Traditional specifications (limited primarily to sensitivity and uptime) are no longer sufficient to successfully integrate a system into a 7 by 24 manufacturing area with multiple systems. Issues such as system sensitivity matching, sensitivity characterization by defect type, operator training and certification standards, and real-time SPC control of the systems must be addressed. This paper outlines some of the techniques Intel Mask Operation uses for integration of a new inspection system into the manufacturing line. Specifically moving a beta- site type tool out of the beta-site mode and into volume production. Examples are presented, including installation for manufacturing (including ergonomic modifications), techniques for system-to-system matching, use of SPC charts to monitor system performance, and operator training/certifications. Relationships between system PMs, or other environmental changes, and the system sensitivity SPC control charts also are discussed.

Noncovalent Polymerization of Mesogens Crystallizes Lysozyme: Correlation between Nonamphiphilic Lyotropic Liquid Crystal Phase and Protein Crystal Formation

PubMed Central

Simon, Karen A.; Shetye, Gauri S.; Englich, Ulrich; Wu, Lei; Luk, Yan-Yeung

2011-01-01

Crystallization of proteins is important for fundamental studies and biopharmaceutical development but remains largely an empirical science. Here, we report the use of organic salts that can form a class of unusual non-amphiphilic lyotropic liquid crystals to crystallize the protein lysozyme. Certain non-amphiphilic organic molecules with fused aromatic rings and two charges can assemble into stable thread-like noncovalent polymers that may further form liquid crystal phases in water, traditionally termed chromonic liquid crystals. Using five of these mesogenic molecules as additives to induce protein crystallization, we discover that molecules that can form liquid crystal phases in water are highly effective at inducing the crystal formation of lysozyme, even at concentrations significantly lower than that required for forming liquid crystal phases. This result reveals an example of inducing protein crystallization by the molecular assembly of the additives, and is consistent with a new mechanism by which the strong hydration of an assembly process provides a gradual means to compete for the water molecules to enable solvated proteins to form crystals. PMID:21786812

Crystallization of the glassy grain boundary phase in silicon nitride ceramics

NASA Technical Reports Server (NTRS)

Drummond, Charles H., III

1991-01-01

The role was studied of the intergranular glassy phase in silicon nitride as-processed with yttria as a sintering aid. The microstructure, crystallization, and viscosity of the glassy phase were areas studied. Crystallization of the intergranular glassy phase to more refractory crystalline phases should improve the high temperature mechanical properties of the silicon nitride. The addition of a nucleating agent will increase the rate of crystallization. The measurement of the viscosity of the glassy phase will permit the estimation of the high temperature deformation of the silicon nitride.

The detective quantum efficiency of photon-counting x-ray detectors using cascaded-systems analyses

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

Tanguay, Jesse; Yun, Seungman; School of Mechanical Engineering, Pusan National University, Jangjeon-dong, Geumjeong-gu, Busan 609-735

Purpose: Single-photon counting (SPC) x-ray imaging has the potential to improve image quality and enable new advanced energy-dependent methods. The purpose of this study is to extend cascaded-systems analyses (CSA) to the description of image quality and the detective quantum efficiency (DQE) of SPC systems. Methods: Point-process theory is used to develop a method of propagating the mean signal and Wiener noise-power spectrum through a thresholding stage (required to identify x-ray interaction events). The new transfer relationships are used to describe the zero-frequency DQE of a hypothetical SPC detector including the effects of stochastic conversion of incident photons to secondarymore » quanta, secondary quantum sinks, additive noise, and threshold level. Theoretical results are compared with Monte Carlo calculations assuming the same detector model. Results: Under certain conditions, the CSA approach can be applied to SPC systems with the additional requirement of propagating the probability density function describing the total number of image-forming quanta through each stage of a cascaded model. Theoretical results including DQE show excellent agreement with Monte Carlo calculations under all conditions considered. Conclusions: Application of the CSA method shows that false counts due to additive electronic noise results in both a nonlinear image signal and increased image noise. There is a window of allowable threshold values to achieve a high DQE that depends on conversion gain, secondary quantum sinks, and additive noise.« less

[Statistical Process Control (SPC) can help prevent treatment errors without increasing costs in radiotherapy].

PubMed

Govindarajan, R; Llueguera, E; Melero, A; Molero, J; Soler, N; Rueda, C; Paradinas, C

2010-01-01

Statistical Process Control (SPC) was applied to monitor patient set-up in radiotherapy and, when the measured set-up error values indicated a loss of process stability, its root cause was identified and eliminated to prevent set-up errors. Set up errors were measured for medial-lateral (ml), cranial-caudal (cc) and anterior-posterior (ap) dimensions and then the upper control limits were calculated. Once the control limits were known and the range variability was acceptable, treatment set-up errors were monitored using sub-groups of 3 patients, three times each shift. These values were plotted on a control chart in real time. Control limit values showed that the existing variation was acceptable. Set-up errors, measured and plotted on a X chart, helped monitor the set-up process stability and, if and when the stability was lost, treatment was interrupted, the particular cause responsible for the non-random pattern was identified and corrective action was taken before proceeding with the treatment. SPC protocol focuses on controlling the variability due to assignable cause instead of focusing on patient-to-patient variability which normally does not exist. Compared to weekly sampling of set-up error in each and every patient, which may only ensure that just those sampled sessions were set-up correctly, the SPC method enables set-up error prevention in all treatment sessions for all patients and, at the same time, reduces the control costs. Copyright © 2009 SECA. Published by Elsevier Espana. All rights reserved.

Systematic assessment of survey scan and MS2-based abundance strategies for label-free quantitative proteomics using high-resolution MS data.

PubMed

Tu, Chengjian; Li, Jun; Sheng, Quanhu; Zhang, Ming; Qu, Jun

2014-04-04

Survey-scan-based label-free method have shown no compelling benefit over fragment ion (MS2)-based approaches when low-resolution mass spectrometry (MS) was used, the growing prevalence of high-resolution analyzers may have changed the game. This necessitates an updated, comparative investigation of these approaches for data acquired by high-resolution MS. Here, we compared survey scan-based (ion current, IC) and MS2-based abundance features including spectral-count (SpC) and MS2 total-ion-current (MS2-TIC), for quantitative analysis using various high-resolution LC/MS data sets. Key discoveries include: (i) study with seven different biological data sets revealed only IC achieved high reproducibility for lower-abundance proteins; (ii) evaluation with 5-replicate analyses of a yeast sample showed IC provided much higher quantitative precision and lower missing data; (iii) IC, SpC, and MS2-TIC all showed good quantitative linearity (R(2) > 0.99) over a >1000-fold concentration range; (iv) both MS2-TIC and IC showed good linear response to various protein loading amounts but not SpC; (v) quantification using a well-characterized CPTAC data set showed that IC exhibited markedly higher quantitative accuracy, higher sensitivity, and lower false-positives/false-negatives than both SpC and MS2-TIC. Therefore, IC achieved an overall superior performance than the MS2-based strategies in terms of reproducibility, missing data, quantitative dynamic range, quantitative accuracy, and biomarker discovery.

Systematic Assessment of Survey Scan and MS2-Based Abundance Strategies for Label-Free Quantitative Proteomics Using High-Resolution MS Data

PubMed Central

2015-01-01

Survey-scan-based label-free method have shown no compelling benefit over fragment ion (MS2)-based approaches when low-resolution mass spectrometry (MS) was used, the growing prevalence of high-resolution analyzers may have changed the game. This necessitates an updated, comparative investigation of these approaches for data acquired by high-resolution MS. Here, we compared survey scan-based (ion current, IC) and MS2-based abundance features including spectral-count (SpC) and MS2 total-ion-current (MS2-TIC), for quantitative analysis using various high-resolution LC/MS data sets. Key discoveries include: (i) study with seven different biological data sets revealed only IC achieved high reproducibility for lower-abundance proteins; (ii) evaluation with 5-replicate analyses of a yeast sample showed IC provided much higher quantitative precision and lower missing data; (iii) IC, SpC, and MS2-TIC all showed good quantitative linearity (R2 > 0.99) over a >1000-fold concentration range; (iv) both MS2-TIC and IC showed good linear response to various protein loading amounts but not SpC; (v) quantification using a well-characterized CPTAC data set showed that IC exhibited markedly higher quantitative accuracy, higher sensitivity, and lower false-positives/false-negatives than both SpC and MS2-TIC. Therefore, IC achieved an overall superior performance than the MS2-based strategies in terms of reproducibility, missing data, quantitative dynamic range, quantitative accuracy, and biomarker discovery. PMID:24635752

Silage or fresh by-product of peach palm as roughage in the feeding of lambs.

PubMed

dos Santos Cabral, Ícaro; Azevêdo, José Augusto Gomes; de Almeida, Flávio Moreira; Pereira, Luiz Gustavo Ribeiro; de Araújo, Gherman Garcia Leal; Nogueira, Abdon Santos; Souza, Lígia Lins; de Oliveira, Gisele Andrade; de Oliveira Filho, Carlos Alberto Alves

2015-03-01

The objective of this study was to evaluate intake and apparent digestibility of agro-industrial by-product of peach palm in diets for lambs. Twenty castrated, crossbred Santa Ines lambs, with average age of 150 days and body weight of 22.4 ± 3.4 kg, were distributed in a completely randomized design with four experimental diets composed of the following: fresh by-product of peach palm enriched with urea + ammonia sulfate (FU); fresh peach palm by-product + concentrate (FP); silage of peach palm by-product + concentrate (SP); and silage of peach palm by-product enriched with 15% of cornmeal + concentrate (SPC). Intake was recorded daily, and the digestibility coefficients were estimated with the internal marker indigestible acid detergent fiber (iADF). Diet FU resulted in the lowest intake and digestibility of the nutrients evaluated. Animals receiving diet FP showed higher intakes of dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber (NDF), total digestible nutrients (TDN), and digestible energy (DE) in relation to animals fed diets SP and SPC. Diets SP and SPC showed higher coefficients of digestibility of DM, OM, CP, and NDF than diet FP. Diet SP reduced the intakes of DM, OM, ether extract (EE), non-fibrous carbohydrate (NFC), TDN, and DE and the digestibility coefficients of DM, OM, and NFC as compared with diet SPC. Feedlot lambs fed a diet with fresh peach palm by-product + concentrate (diet FP) have higher nutrient intake.

Shock and Microstructural Characterization of the α-ω Phase Transition in Titanium Crystals

NASA Astrophysics Data System (ADS)

Morrow, Benjamin M.; Rigg, Paulo A.; Jones, David R.; Addessio, Francis L.; Trujillo, Carl P.; Saavedra, Ramon A.; Martinez, Daniel T.; Cerreta, Ellen K.

2017-12-01

A multicrystal comprised of a small number of large crystals of high-purity titanium and a [0001] oriented high-purity single crystal titanium sample were shock loaded using gas gun plate impact experiments. Tests were performed at stresses above the α {-}ω phase transition stress (for high-purity polycrystalline specimens) to observe the behavior of oriented crystals under similar conditions. Post-mortem characterization of the shocked microstructure was conducted on the single crystal sample to measure textures, and quantify phases and twinning. The apparent activation of plastic and transformation mechanisms was dependent upon crystal orientation. Specifically, the [0001] crystal showed a higher Hugoniot elastic limit than the [10\\bar{1}0] or [3\\bar{1}\\bar{4}4] orientations. The slope of velocity as a function of time was lower in the [0001] orientation than the other orientations during plastic deformation, indicating sluggish transformation kinetics for the α to ω phase transition for the [0001] oriented crystal. Microtexture measurements of a recovered [0001] oriented single crystal revealed the presence of retained ω phase after unloading, with orientations of the constituent phase fractions indicative of the forward α → ω transition, rather than the reverse ω → α transition, suggesting that the material never achieved a state of 100% ω phase.

Preliminary experiments on phase conjugation for flow visualization. [barium titanate single crystals

NASA Technical Reports Server (NTRS)

Weimer, D.; Howes, W. L.

1984-01-01

Barium titanate single crystals are discussed in the context of: the procedure for polarizing a crystal; a test for phase conjugation; transients in the production of phase conjugation; real time readout by a separate laser of a hologram induced within the crystal, including conjugation response times to on-off switching of each beam; and a demonstration of a Twyman-Green interferometer utilizing phase conjugation.

Phase Separation and Crystallization of Hemoglobin C in Transgenic Mouse and Human Erythrocytes

PubMed Central

Canterino, Joseph E.; Galkin, Oleg; Vekilov, Peter G.; Hirsch, Rhoda Elison

2008-01-01

Individuals expressing hemoglobin C (β6 Glu→Lys) present red blood cells (RBC) with intraerythrocytic crystals that form when hemoglobin (Hb) is oxygenated. Our earlier in vitro liquid-liquid (L-L) phase separation studies demonstrated that liganded HbC exhibits a stronger net intermolecular attraction with a longer range than liganded HbS or HbA, and that L-L phase separation preceded and enhanced crystallization. We now present evidence for the role of phase separation in HbC crystallization in the RBC, and the role of the RBC membrane as a nucleation center. RBC obtained from both human homozygous HbC patients and transgenic mice expressing only human HbC were studied by bright-field and differential interference contrast video-enhanced microscopy. RBC were exposed to hypertonic NaCl solution (1.5–3%) to induce crystallization within an appropriate experimental time frame. L-L phase separation occurred inside the RBC, which in turn enhanced the formation of intraerythrocytic crystals. RBC L-L phase separation and crystallization comply with the thermodynamic and kinetics laws established through in vitro studies of phase transformations. This is the first report, to the best of our knowledge, to capture a temporal view of intraerythrocytic HbC phase separation, crystal formation, and dissolution. PMID:18621841

Labelling and 'Dear Doctor' letters: are they noncommittal?

PubMed

van Grootheest, A C Kees; Edwards, I Ralph

2002-01-01

Over the past few years, a number of drugs have been withdrawn for safety reasons, either by drug approval authorities, or by the manufacturer. A recent example is the withdrawal of cerivastatin in connection with rhabdomyolysis. Several other drugs have also been taken off the market as a security measure, not because the nature of the risk involved was unknown but because the risk had proved apparently uncontainable. It seems that the inclusion of a warning or contraindication in the Summary of Product Characteristics (SPC) or sending a 'Dear Doctor' letter is insufficient to ensure compliant prescription behaviour. There appears to be a discrepancy between the careful use of evidence underpinning the SPC content and formal warnings and changes to the SPC and the effect they have on the prescription and dispensing of the drugs involved. This results in undue loss or damage for both the manufacturer and the patient. There are no easy solutions to tackle this problem; the ineffectiveness of labelling and 'Dear Doctor' letters has ramifications for the whole regulatory/ industrial/educational complex. We discuss briefly four possible strategies for improving the current situation, with the emphasis on the place the prescriber has in this process. The first strategy is education-based. Clinicians need to know about the comparative merits of the effectiveness and risk of drugs, as well as how they work pharmacologically, toxicologically, and what interactions they have with each other. The second strategy involves improving the information available for clinicians. Frequently, physicians do not consult the SPC for verification, leaving aside whether they have taken notice of the contents of the official SPC in the first place. It is recommended that the accessibility of SPCs is enhanced for doctors and pharmacists, drawing attention specifically to any changes. There needs to be a single body of information that covers every drug. The third strategy involves communication. There is much to be done in this area both in terms of follow-up and understanding of health professional's behaviour and how to empower best practise. The final strategy involves professional freedom. It goes without saying that doctors who issue off-label prescriptions may need to justify their actions. Deviating from the SPC should always be a considered decision and health professionals need to be aware of the additional responsibilities associated with such a decision. The dispensing pharmacist can play an important role in the implementation of warnings and contraindications.

Spirochaeta psychrophila sp. nov., a psychrophilic spirochaete isolated from subseafloor sediment, and emended description of the genus Spirochaeta.

PubMed

Miyazaki, Masayuki; Sakai, Sanae; Yamanaka, Yuko; Saito, Yumi; Takai, Ken; Imachi, Hiroyuki

2014-08-01

An obligately anaerobic, psychrophilic spirochaete, strain MO-SPC1(T), was isolated from a methanogenic microbial community grown in a continuous-flow bioreactor. Originally, this community was obtained from subseafloor sediments off the Shimokita Peninsula of Japan in the north-western Pacific Ocean. The cells were motile, Gram-stain-negative, helical, 0.25-0.55×3.6-15 µm, with a wavelength of approximately 0.5-0.6 µm. Strain MO-SPC1(T) grew at 0-18 °C (optimally at 15 °C), at pH 6.0-7.5 (optimally at pH 6.8-7.0) and in 20-70 g NaCl l(-1) (optimally at 30-40 NaCl l(-1)). The strain grew chemo-organotrophically with mono-, di- and polysaccharides. The major end products of glucose fermentation were acetate, ethanol, hydrogen and carbon dioxide. The abundant polar lipids of strain MO-SPC1(T) were diphosphatidylglycerol, phosphatidylglycerol, unknown phospholipids and an unknown lipid. The major cellular fatty acids (>5% of the total) were C(14 : 0), C(16 : 0), iso-C(13 : 0), iso-C(14 : 0), iso-C(15 : 0), anteiso-C(13 : 0) and anteiso-C(15 : 0). To the best of our knowledge, this is the first report of the fatty acids iso-C(13 : 0) and anteiso-C(13 : 0) from a species of the genus Spirochaeta. Isoprenoid quinones were not found. The G+C content of the genomic DNA was 39.8 mol%. 16S rRNA gene sequence-based phylogenetic analysis showed that strain MO-SPC1(T) was affiliated with the genus Spirochaeta, and its closest relatives were Spirochaeta isovalerica MA-2(T) (95.6% sequence identity) and Spirochaeta litoralis R1(T) (89.4%). Based on its phenotypic characteristics and phylogenetic traits, strain MO-SPC1(T) is placed in a separate taxon at the level of a novel species within the genus Spirochaeta, for which the name Spirochaeta psychrophila sp. nov. is proposed, reflecting its true psychrophilic physiology. The type strain is MO-SPC1(T) ( = JCM 17280(T) = DSM 23951(T)). To our knowledge, this is the first report of an isolate of the phylum Spirochaetes from a deep-sea sedimentary environment, and of an obligately psychrophilic nature. © 2014 IUMS.

Quantum Liquid Crystal Phases in Strongly Correlated Fermionic Systems

ERIC Educational Resources Information Center

Sun, Kai

2009-01-01

This thesis is devoted to the investigation of the quantum liquid crystal phases in strongly correlated electronic systems. Such phases are characterized by their partially broken spatial symmetries and are observed in various strongly correlated systems as being summarized in Chapter 1. Although quantum liquid crystal phases often involve…

Observation of solid–solid transitions in 3D crystals of colloidal superballs

PubMed Central

Meijer, Janne-Mieke; Pal, Antara; Ouhajji, Samia; Lekkerkerker, Henk N. W.; Philipse, Albert P.; Petukhov, Andrei V.

2017-01-01

Self-organization in anisotropic colloidal suspensions leads to a fascinating range of crystal and liquid crystal phases induced by shape alone. Simulations predict the phase behaviour of a plethora of shapes while experimental realization often lags behind. Here, we present the experimental phase behaviour of superball particles with a shape in between that of a sphere and a cube. In particular, we observe the formation of a plastic crystal phase with translational order and orientational disorder, and the subsequent transformation into rhombohedral crystals. Moreover, we uncover that the phase behaviour is richer than predicted, as we find two distinct rhombohedral crystals with different stacking variants, namely hollow-site and bridge-site stacking. In addition, for slightly softer interactions we observe a solid–solid transition between the two. Our investigation brings us one step closer to ultimately controlling the experimental self-assembly of superballs into functional materials, such as photonic crystals. PMID:28186101

fcc-bcc phase transition in plasma crystals using time-resolved measurements

NASA Astrophysics Data System (ADS)

Dietz, C.; Bergert, R.; Steinmüller, B.; Kretschmer, M.; Mitic, S.; Thoma, M. H.

2018-04-01

Three-dimensional plasma crystals are often described as Yukawa systems for which a phase transition between the crystal structures fcc and bcc has been predicted. However, experimental investigations of this transition are missing. We use a fast scanning video camera to record the crystallization process of 70 000 microparticles and investigate the existence of the fcc-bcc phase transition at neutral gas pressures of 30, 40, and 50 Pa. To analyze the crystal, robust phase diagrams with the help of a machine learning algorithm are calculated. This work shows that the phase transition can be investigated experimentally and makes a comparison with numerical results of Yukawa systems. The phase transition is analyzed in dependence on the screening parameter and structural order. We suggest that the transition is an effect of gravitational compression of the plasma crystal. Experimental investigations of the fcc-bcc phase transition will provide an opportunity to estimate the coupling strength Γ by comparison with numerical results of Yukawa systems.

Formulation of a Broad-Spectrum, All-Weather, Solid-Based, Peracetate - Solvent Dry Decontaminant Concentrate

DTIC Science & Technology

2010-04-01

PAB 17 2.5.2 PAB/SPC Mixtures 17 2.5.3 PAB/SPC Mixtures with Ethylene Carbonate 19 2.5.4 Peroxydone/PAB Mixtures 19 2.5.4.1 Chem Agent Testing 19...Effect of Surfactant and Ethylene Carbonate (EC) Penetrant on Decontamination of HD on CARC Painted Panels 20 5. Effect of Surfactant, Alone, on...previous peroxide-based decontaminants7൓ (i.e., Triton® X-100 (non-ionic surfactant) and propylene carbonate [PC]) could not be used. However, there

Pressure-induced transformations in glassy water: A computer simulation study using the TIP4P/2005 model

NASA Astrophysics Data System (ADS)

Wong, Jessina; Jahn, David A.; Giovambattista, Nicolas

2015-08-01

We study the pressure-induced transformations between low-density amorphous (LDA) and high-density amorphous (HDA) ice by performing out-of-equilibrium molecular dynamics (MD) simulations. We employ the TIP4P/2005 water model and show that this model reproduces qualitatively the LDA-HDA transformations observed experimentally. Specifically, the TIP4P/2005 model reproduces remarkably well the (i) structure (OO, OH, and HH radial distribution functions) and (ii) densities of LDA and HDA at P = 0.1 MPa and T = 80 K, as well as (iii) the qualitative behavior of ρ(P) during compression-induced LDA-to-HDA and decompression-induced HDA-to-LDA transformations. At the rates explored, the HDA-to-LDA transformation is less pronounced than in experiments. By studying the LDA-HDA transformations for a broad range of compression/decompression temperatures, we construct a "P-T phase diagram" for glassy water that is consistent with experiments and remarkably similar to that reported previously for ST2 water. This phase diagram is not inconsistent with the possibility of TIP4P/2005 water exhibiting a liquid-liquid phase transition at low temperatures. A comparison with previous MD simulation studies of SPC/E and ST2 water as well as experiments indicates that, overall, the TIP4P/2005 model performs better than the SPC/E and ST2 models. The effects of cooling and compression rates as well as aging on our MD simulations results are also discussed. The MD results are qualitatively robust under variations of cooling/compression rates (accessible in simulations) and are not affected by aging the hyperquenched glass for at least 1 μs. A byproduct of this work is the calculation of TIP4P/2005 water's diffusion coefficient D(T) at P = 0.1 MPa. It is found that, for T ≥ 210 K, D(T) ≈ (T - TMCT)-γ as predicted by mode coupling theory and in agreement with experiments. For TIP4P/2005 water, TMCT = 209 K and γ = 2.14, very close to the corresponding experimental values TMCT = 221 K and γ = 2.2.

Pressure-induced transformations in glassy water: A computer simulation study using the TIP4P/2005 model.

PubMed

Wong, Jessina; Jahn, David A; Giovambattista, Nicolas

2015-08-21

We study the pressure-induced transformations between low-density amorphous (LDA) and high-density amorphous (HDA) ice by performing out-of-equilibrium molecular dynamics (MD) simulations. We employ the TIP4P/2005 water model and show that this model reproduces qualitatively the LDA-HDA transformations observed experimentally. Specifically, the TIP4P/2005 model reproduces remarkably well the (i) structure (OO, OH, and HH radial distribution functions) and (ii) densities of LDA and HDA at P = 0.1 MPa and T = 80 K, as well as (iii) the qualitative behavior of ρ(P) during compression-induced LDA-to-HDA and decompression-induced HDA-to-LDA transformations. At the rates explored, the HDA-to-LDA transformation is less pronounced than in experiments. By studying the LDA-HDA transformations for a broad range of compression/decompression temperatures, we construct a "P-T phase diagram" for glassy water that is consistent with experiments and remarkably similar to that reported previously for ST2 water. This phase diagram is not inconsistent with the possibility of TIP4P/2005 water exhibiting a liquid-liquid phase transition at low temperatures. A comparison with previous MD simulation studies of SPC/E and ST2 water as well as experiments indicates that, overall, the TIP4P/2005 model performs better than the SPC/E and ST2 models. The effects of cooling and compression rates as well as aging on our MD simulations results are also discussed. The MD results are qualitatively robust under variations of cooling/compression rates (accessible in simulations) and are not affected by aging the hyperquenched glass for at least 1 μs. A byproduct of this work is the calculation of TIP4P/2005 water's diffusion coefficient D(T) at P = 0.1 MPa. It is found that, for T ≥ 210 K, D(T) ≈ (T - T(MCT))(-γ) as predicted by mode coupling theory and in agreement with experiments. For TIP4P/2005 water, T(MCT) = 209 K and γ = 2.14, very close to the corresponding experimental values T(MCT) = 221 K and γ = 2.2.

Cupric oxide inclusions in cuprous oxide crystals grown by the floating zone method

NASA Astrophysics Data System (ADS)

Frazer, Laszlo; Chang, Kelvin B.; Poeppelmeier, Kenneth R.; Ketterson, John B.

2015-06-01

Phase-pure cuprous oxide (Cu2O) crystals are difficult to grow since cupric oxide can form within the crystal as the crystal is cooled to ambient conditions. Vacancies are the solute which causes precipitation of macroscopic defects. Therefore, even when a mostly phase-pure single crystal is used as a feed rod, cupric oxide inclusions persist in the recrystallized solid. Control of the thermal profile during crystal growth, however, can improve phase-purity; a slow counter-rotation rate of the feed and seed rods results in fewer inclusions. Cupric oxide can be removed by annealing, which produces a factor of 540 ± 70 increase in phase-purity.

Cupric oxide inclusions in cuprous oxide crystals grown by the floating zone method

PubMed Central

Frazer, Laszlo; Chang, Kelvin B; Poeppelmeier, Kenneth R; Ketterson, John B

2015-01-01

Phase-pure cuprous oxide (Cu2O) crystals are difficult to grow since cupric oxide can form within the crystal as the crystal is cooled to ambient conditions. Vacancies are the solute which causes precipitation of macroscopic defects. Therefore, even when a mostly phase-pure single crystal is used as a feed rod, cupric oxide inclusions persist in the recrystallized solid. Control of the thermal profile during crystal growth, however, can improve phase-purity; a slow counter-rotation rate of the feed and seed rods results in fewer inclusions. Cupric oxide can be removed by annealing, which produces a factor of 540 ± 70 increase in phase-purity. PMID:27877798

Formation of the molecular crystal structure during the vacuum sublimation of paracetamol

NASA Astrophysics Data System (ADS)

Belyaev, A. P.; Rubets, V. P.; Antipov, V. V.; Bordei, N. S.

2015-04-01

The results from structural and thermal studies on the formation of molecular crystals during the vacuum sublimation of paracetamol from its vapor phase are given. It is established that the vapor-crystal phase transition proceeds in a complicated way as the superposition of two phase transitions: a first-order phase transition with a change in density, and a second-order phase transition with a change in ordering. It is shown that the latter is a smeared phase transition that proceeds with the formation of a pretransitional phase that is irreversibly dissipated during phase transformation, leading to the formation of crystals of the rhombic syngony. Data from differential scanning calorimetry and X-ray diffraction analysis are presented along with microphotographs.

Defect-induced local variation of crystal phase transition temperature in metal-halide perovskites.

PubMed

Dobrovolsky, Alexander; Merdasa, Aboma; Unger, Eva L; Yartsev, Arkady; Scheblykin, Ivan G

2017-06-26

Solution-processed organometal halide perovskites are hybrid crystalline semiconductors highly interesting for low-cost and efficient optoelectronics. Their properties are dependent on the crystal structure. Literature shows a variety of crystal phase transition temperatures and often a spread of the transition over tens of degrees Kelvin. We explain this inconsistency by demonstrating that the temperature of the tetragonal-to-orthorhombic phase transition in methylammonium lead triiodide depends on the concentration and nature of local defects. Phase transition in individual nanowires was studied by photoluminescence microspectroscopy and super-resolution imaging. We propose that upon cooling from 160 to 140 K, domains of the crystal containing fewer defects stay in the tetragonal phase longer than highly defected domains that readily transform to the high bandgap orthorhombic phase at higher temperatures. The existence of relatively pure tetragonal domains during the phase transition leads to drastic photoluminescence enhancement, which is inhomogeneously distributed across perovskite microcrystals.Understanding crystal phase transition in materials is of fundamental importance. Using luminescence spectroscopy and super-resolution imaging, Dobrovolsky et al. study the transition from the tetragonal to orthorhombic crystal phase in methylammonium lead triiodide nanowires at low temperature.

Solar Wind Electrons Alphas and Protons (SWEAP) Investigation: Design of the Solar Wind and Coronal Plasma Instrument Suite for Solar Probe Plus

NASA Astrophysics Data System (ADS)

Kasper, Justin C.; Abiad, Robert; Austin, Gerry; Balat-Pichelin, Marianne; Bale, Stuart D.; Belcher, John W.; Berg, Peter; Bergner, Henry; Berthomier, Matthieu; Bookbinder, Jay; Brodu, Etienne; Caldwell, David; Case, Anthony W.; Chandran, Benjamin D. G.; Cheimets, Peter; Cirtain, Jonathan W.; Cranmer, Steven R.; Curtis, David W.; Daigneau, Peter; Dalton, Greg; Dasgupta, Brahmananda; DeTomaso, David; Diaz-Aguado, Millan; Djordjevic, Blagoje; Donaskowski, Bill; Effinger, Michael; Florinski, Vladimir; Fox, Nichola; Freeman, Mark; Gallagher, Dennis; Gary, S. Peter; Gauron, Tom; Gates, Richard; Goldstein, Melvin; Golub, Leon; Gordon, Dorothy A.; Gurnee, Reid; Guth, Giora; Halekas, Jasper; Hatch, Ken; Heerikuisen, Jacob; Ho, George; Hu, Qiang; Johnson, Greg; Jordan, Steven P.; Korreck, Kelly E.; Larson, Davin; Lazarus, Alan J.; Li, Gang; Livi, Roberto; Ludlam, Michael; Maksimovic, Milan; McFadden, James P.; Marchant, William; Maruca, Bennet A.; McComas, David J.; Messina, Luciana; Mercer, Tony; Park, Sang; Peddie, Andrew M.; Pogorelov, Nikolai; Reinhart, Matthew J.; Richardson, John D.; Robinson, Miles; Rosen, Irene; Skoug, Ruth M.; Slagle, Amanda; Steinberg, John T.; Stevens, Michael L.; Szabo, Adam; Taylor, Ellen R.; Tiu, Chris; Turin, Paul; Velli, Marco; Webb, Gary; Whittlesey, Phyllis; Wright, Ken; Wu, S. T.; Zank, Gary

2016-12-01

The Solar Wind Electrons Alphas and Protons (SWEAP) Investigation on Solar Probe Plus is a four sensor instrument suite that provides complete measurements of the electrons and ionized helium and hydrogen that constitute the bulk of solar wind and coronal plasma. SWEAP consists of the Solar Probe Cup (SPC) and the Solar Probe Analyzers (SPAN). SPC is a Faraday Cup that looks directly at the Sun and measures ion and electron fluxes and flow angles as a function of energy. SPAN consists of an ion and electron electrostatic analyzer (ESA) on the ram side of SPP (SPAN-A) and an electron ESA on the anti-ram side (SPAN-B). The SPAN-A ion ESA has a time of flight section that enables it to sort particles by their mass/charge ratio, permitting differentiation of ion species. SPAN-A and -B are rotated relative to one another so their broad fields of view combine like the seams on a baseball to view the entire sky except for the region obscured by the heat shield and covered by SPC. Observations by SPC and SPAN produce the combined field of view and measurement capabilities required to fulfill the science objectives of SWEAP and Solar Probe Plus. SWEAP measurements, in concert with magnetic and electric fields, energetic particles, and white light contextual imaging will enable discovery and understanding of solar wind acceleration and formation, coronal and solar wind heating, and particle acceleration in the inner heliosphere of the solar system. SPC and SPAN are managed by the SWEAP Electronics Module (SWEM), which distributes power, formats onboard data products, and serves as a single electrical interface to the spacecraft. SWEAP data products include ion and electron velocity distribution functions with high energy and angular resolution. Full resolution data are stored within the SWEM, enabling high resolution observations of structures such as shocks, reconnection events, and other transient structures to be selected for download after the fact. This paper describes the implementation of the SWEAP Investigation, the driving requirements for the suite, expected performance of the instruments, and planned data products, as of mission preliminary design review.

Drug utilization and off-label drug use in Spanish pediatric gastroenterology outpatients.

PubMed

Ruíz-Antorán, Belén; Piñeiro, Roi; Avendaño, Cristina; Román, Enriqueta; Cilleruelo, María Luz; Gutiérrez-Junquera, Carolina; Centeno, Gustavo; Cilleruelo, María José

2013-02-01

The clinical use of medicines outside the conditions authorized in their Summary of Product Characteristics (SPC) (off-label use) is a common practice in pediatrics. The aim of the present study was to describe and quantify the medicines received by children attended in the pediatric gastroenterology department, their off-label use, and compliance with accepted rules for said use. A retrospective observational study was performed on all of the patients who had their first consultation in pediatric gastroenterology between January 1 and October 31, 2010. All of the clinical information and medicines prescribed were analyzed. Off-label use was defined as the use of medicines in indications not included in the officially approved SPC or in ages not included or recommended in the SPC as well as the use of doses, intervals, or administration routes different from those considered in the SPC. A total of 695 patients (52.8% male) were included, 48.2% younger than 2 years. Two-hundred seven patients (29.8%) received 331 prescriptions. The most commonly used medicines were anti-H2 and proton pump inhibitors. Of all the prescriptions, 33.2% were considered off-label, and up to 47.3% of the prescribed patients had at least 1 medicine under off-label conditions. The medical records contained no documentation on information given to the parents regarding off-label use. The study found a high percentage of off-label use of medicines in the Pediatric Gastroenterology outpatient setting, especially in children younger than 2 years. Several initiatives were derived from the present study and implemented in our hospital.

Cis-acting sequences from a human surfactant protein gene confer pulmonary-specific gene expression in transgenic mice

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

Korfhagen, T.R.; Glasser, S.W.; Wert, S.E.

1990-08-01

Pulmonary surfactant is produced in late gestation by developing type II epithelial cells lining the alveolar epithelium of the lung. Lack of surfactant at birth is associated with respiratory distress syndrome in premature infants. Surfactant protein C (SP-C) is a highly hydrophobic peptide isolated from pulmonary tissue that enhances the biophysical activity of surfactant phospholipids. Like surfactant phospholipid, SP-C is produced by epithelial cells in the distal respiratory epithelium, and its expression increases during the latter part of gestation. A chimeric gene containing 3.6 kilobases of the promoter and 5{prime}-flanking sequences of the human SP-C gene was used to expressmore » diphtheria toxin A. The SP-C-diphtheria toxin A fusion gene was injected into fertilized mouse eggs to produce transgenic mice. Affected mice developed respiratory failure in the immediate postnatal period. Morphologic analysis of lungs from affected pups showed variable but severe cellular injury confined to pulmonary tissues. Ultrastructural changes consistent with cell death and injury were prominent in the distal respiratory epithelium. Proximal components of the tracheobronchial tree were not severely affected. Transgenic animals were of normal size at birth, and structural abnormalities were not detected in nonpulmonary tissues. Lung-specific diphtheria toxin A expression controlled by the human SP-C gene injured type II epithelial cells and caused extensive necrosis of the distal respiratory epithelium. The absence of type I epithelial cells in the most severely affected transgenic animals supports the concept that developing type II cells serve as precursors to type I epithelial cells.« less

Evaluation of a combinatorial approach to prion inactivation using an oxidizing agent, SDS, and proteinase K.

PubMed

Smith, Jodi D; Nicholson, Eric M; Greenlee, Justin J

2013-07-25

Prions demonstrate an unusual resistance to methods effective at inactivating conventional microorganisms. This has resulted in a very tangible and difficult infection control challenge to the medical and veterinary communities, as well as animal agriculture and related industries. Currently accepted practices of harsh chemical treatments such as prolonged exposure to sodium hydroxide or sodium hypochlorite, or autoclaving are not suitable in many situations. Less caustic and more readily applicable treatments to contaminated environments are therefore desirable. We recently demonstrated that exposure of the RML scrapie agent to a commercial product containing sodium percarbonate (SPC-P) with or without sodium dodecyl sulfate (SDS) rendered PrP(Sc) sensitive to proteinase K (PK), but did not eliminate infectivity. The current study was designed to evaluate the efficacy of a combinatorial approach to inactivating prions by exposing RML-positive brain homogenate to SPC-P and SDS followed by PK. Treated samples were evaluated for PrP(Sc)-immunoreactivity by western blot, and residual infectivity by mouse bioassay. Treatment of infected brain homogenate with SPC-P and SDS followed by PK exposure resulted in a 4-5 log10 reduction in infectivity when bioassayed in tga20 mice. This study demonstrates that exposure of the RML scrapie agent to SPC-P and SDS followed by PK markedly reduces, but does not eliminate infectivity. The results of this study encourage further investigation into whether consecutive or concomitant exposure to sodium percarbonate, SDS, and a protease may serve as a viable and non-caustic option for prion inactivation.

Extremely stable soluble high molecular mass multi-protein complex with DNase activity in human placental tissue.

PubMed

Burkova, Evgeniya E; Dmitrenok, Pavel S; Sedykh, Sergey E; Buneva, Valentina N; Soboleva, Svetlana E; Nevinsky, Georgy A

2014-01-01

Human placenta is an organ which protects, feeds, and regulates the grooving of the embryo. Therefore, identification and characterization of placental components including proteins and their multi-protein complexes is an important step to understanding the placenta function. We have obtained and analyzed for the first time an extremely stable multi-protein complex (SPC, ∼ 1000 kDa) from the soluble fraction of three human placentas. By gel filtration on Sepharose-4B, the SPC was well separated from other proteins of the placenta extract. Light scattering measurements and gel filtration showed that the SPC is stable in the presence of NaCl, MgCl2, acetonitrile, guanidinium chloride, and Triton in high concentrations, but dissociates efficiently in the presence of 8 M urea, 50 mM EDTA, and 0.5 M NaCl. Such a stable complex is unlikely to be a casual associate of different proteins. According to SDS-PAGE and MALDI mass spectrometry data, this complex contains many major glycosylated proteins with low and moderate molecular masses (MMs) 4-14 kDa and several moderately abundant (79.3, 68.5, 52.8, and 27.2 kDa) as well as minor proteins with higher MMs. The SPC treatment with dithiothreitol led to a disappearance of some protein bands and revealed proteins with lower MMs. The SPCs from three placentas efficiently hydrolyzed plasmid supercoiled DNA with comparable rates and possess at least two DNA-binding sites with different affinities for a 12-mer oligonucleotide. Progress in study of placental protein complexes can promote understanding of their biological functions.

Synthesis of Caffeine/Maleic Acid Co-crystal by Ultrasound-assisted Slurry Co-crystallization.

PubMed

Apshingekar, Prafulla P; Aher, Suyog; Kelly, Adrian L; Brown, Elaine C; Paradkar, Anant

2017-01-01

A green approach has been used for co-crystallization of noncongruent co-crystal pair of caffeine/maleic acid using water. Ultrasound is known to affect crystallization; hence, the effect of high power ultrasound on the ternary phase diagram has been investigated in detail using a slurry co-crystallization approach. A systematic investigation was performed to understand how the accelerated conditions during ultrasound-assisted co-crystallization will affect different regions of the ternary phase diagram. Application of ultrasound showed considerable effect on the ternary phase diagram, principally on caffeine/maleic acid 2:1 (disappeared) and 1:1 co-crystal (narrowed) regions. Also, the stability regions for pure caffeine and maleic acid in water were narrowed in the presence of ultrasound, expanding the solution region. The observed effect of ultrasound on the phase diagram was correlated with solubility of caffeine and maleic acid and stability of co-crystal forms in water. Copyright © 2016. Published by Elsevier Inc.

Atomic density functional and diagram of structures in the phase field crystal model

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

Ankudinov, V. E., E-mail: vladimir@ankudinov.org; Galenko, P. K.; Kropotin, N. V.

2016-02-15

The phase field crystal model provides a continual description of the atomic density over the diffusion time of reactions. We consider a homogeneous structure (liquid) and a perfect periodic crystal, which are constructed from the one-mode approximation of the phase field crystal model. A diagram of 2D structures is constructed from the analytic solutions of the model using atomic density functionals. The diagram predicts equilibrium atomic configurations for transitions from the metastable state and includes the domains of existence of homogeneous, triangular, and striped structures corresponding to a liquid, a body-centered cubic crystal, and a longitudinal cross section of cylindricalmore » tubes. The method developed here is employed for constructing the diagram for the homogeneous liquid phase and the body-centered iron lattice. The expression for the free energy is derived analytically from density functional theory. The specific features of approximating the phase field crystal model are compared with the approximations and conclusions of the weak crystallization and 2D melting theories.« less

On the synthesis of AlPO4-21 molecular sieve by vapor phase transport method and its phase transformation to AlPO4-15 molecular sieve

NASA Astrophysics Data System (ADS)

Shao, Hui; Chen, Jingjing; Chen, Xia; Leng, Yixin; Zhong, Jing

2015-04-01

An experimental design was applied to the synthesis of AlPO4-21 molecular sieve (AWO structure) by vapor phase transport (VPT) method, using tetramethylguanidine (TMG) as the template. In this study, the effects of crystallization time, crystallization temperature, phosphor content, template content and water content in the synthesis gel were investigated. The materials obtained were characterized by X-ray diffraction, scanning electron microscopy and fourier transform infrared spectroscopy (FT-IR). Microstructural analysis of the crystal growth in vapor synthetic conditions revealed a revised crystal growth route from zeolite AlPO4-21 to AlPO4-15 in the presence of the TMG. Homogenous hexagonal prism AlPO4-21 crystals with size of 7 × 3 μm were synthesized at a lower temperature (120 °C), which were completely different from the typical tabular parallelogram crystallization microstructure of AlPO4-21 phase. The crystals were transformed into AlPO4-21 phase with higher crystallization temperature, longer crystallization time, higher P2O5/Al2O3 ratio and higher TMG/Al2O3 ratio.

Economic Statistical Design of Integrated X-bar-S Control Chart with Preventive Maintenance and General Failure Distribution

PubMed Central

Caballero Morales, Santiago Omar

2013-01-01

The application of Preventive Maintenance (PM) and Statistical Process Control (SPC) are important practices to achieve high product quality, small frequency of failures, and cost reduction in a production process. However there are some points that have not been explored in depth about its joint application. First, most SPC is performed with the X-bar control chart which does not fully consider the variability of the production process. Second, many studies of design of control charts consider just the economic aspect while statistical restrictions must be considered to achieve charts with low probabilities of false detection of failures. Third, the effect of PM on processes with different failure probability distributions has not been studied. Hence, this paper covers these points, presenting the Economic Statistical Design (ESD) of joint X-bar-S control charts with a cost model that integrates PM with general failure distribution. Experiments showed statistically significant reductions in costs when PM is performed on processes with high failure rates and reductions in the sampling frequency of units for testing under SPC. PMID:23527082

A Database of Tornado Events as Perceived by the USArray Transportable Array Network

NASA Astrophysics Data System (ADS)

Tytell, J. E.; Vernon, F.; Reyes, J. C.

2015-12-01

Over the course of the deployment of Earthscope's USArray Transportable Array (TA) network there have numerous tornado events that have occurred within the changing footprint of its network. The Array Network Facility based in San Diego, California, has compiled a database of these tornado events based on data provided by the NOAA Storm Prediction Center (SPC). The SPC data itself consists of parameters such as start-end point track data for each event, maximum EF intensities, and maximum track widths. Our database is Antelope driven and combines these data from the SPC with detailed station information from the TA network. We are now able to list all available TA stations during any specific tornado event date and also provide a single calculated "nearest" TA station per individual tornado event. We aim to provide this database as a starting resource for those with an interest in investigating tornado signatures within surface pressure and seismic response data. On a larger scale, the database may be of particular interest to the infrasound research community

Product/Process (P/P) Models For The Defense Waste Processing Facility (DWPF): Model Ranges And Validation Ranges For Future Processing

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

Jantzen, C.; Edwards, T.

Radioactive high level waste (HLW) at the Savannah River Site (SRS) has successfully been vitrified into borosilicate glass in the Defense Waste Processing Facility (DWPF) since 1996. Vitrification requires stringent product/process (P/P) constraints since the glass cannot be reworked once it is poured into ten foot tall by two foot diameter canisters. A unique “feed forward” statistical process control (SPC) was developed for this control rather than statistical quality control (SQC). In SPC, the feed composition to the DWPF melter is controlled prior to vitrification. In SQC, the glass product would be sampled after it is vitrified. Individual glass property-compositionmore » models form the basis for the “feed forward” SPC. The models transform constraints on the melt and glass properties into constraints on the feed composition going to the melter in order to guarantee, at the 95% confidence level, that the feed will be processable and that the durability of the resulting waste form will be acceptable to a geologic repository.« less

Treatment of complex Remazol dye effluent using sawdust- and coal-based activated carbons.

PubMed

Vijayaraghavan, K; Won, Sung Wook; Yun, Yeoung-Sang

2009-08-15

A complex Remazol dye effluent, comprised of four reactive dyes and auxiliary chemicals, was decolorized using SPS-200 (sawdust-based) and SPC-100 (coal-based) activated carbons. A detailed characterization revealed that the pore diameter of the activated carbon played an important role in dye adsorption. The solution pH had no significant effect on the adsorption capacity in the pH range of 2-10.7. According to the Langmuir model, the maximum uptakes of SPS-200 were 415.4, 510.3, 368.5 and 453.0 mg g(-1) for Reactive Black 5 (RB5), Reactive Orange 16 (RO16), Remazol Brilliant Blue R (RBBR) and Remazol Brilliant Violet 5R (RBV), respectively. Conversely, those of SPC-100 were slightly lower, at 150.8, 197.4, 178.3 and 201.1 mg g(-1) for RB5, RO16, RBBR and RBV, respectively. In the case of Remazol effluent, SPS-200 exhibited a decolorization efficiency of 100% under unadjusted pH conditions at 10.7, compared to that of 52% for SPC-100.

Design of experiments enhanced statistical process control for wind tunnel check standard testing

NASA Astrophysics Data System (ADS)

Phillips, Ben D.

The current wind tunnel check standard testing program at NASA Langley Research Center is focused on increasing data quality, uncertainty quantification and overall control and improvement of wind tunnel measurement processes. The statistical process control (SPC) methodology employed in the check standard testing program allows for the tracking of variations in measurements over time as well as an overall assessment of facility health. While the SPC approach can and does provide researchers with valuable information, it has certain limitations in the areas of process improvement and uncertainty quantification. It is thought by utilizing design of experiments methodology in conjunction with the current SPC practices that one can efficiently and more robustly characterize uncertainties and develop enhanced process improvement procedures. In this research, methodologies were developed to generate regression models for wind tunnel calibration coefficients, balance force coefficients and wind tunnel flow angularities. The coefficients of these regression models were then tracked in statistical process control charts, giving a higher level of understanding of the processes. The methodology outlined is sufficiently generic such that this research can be applicable to any wind tunnel check standard testing program.

Testing the Solar Probe Cup, An Instrument Designed to Touch The Sun

NASA Technical Reports Server (NTRS)

Whittlesey, Phyllis; Case, Anthony; Kasper, Justin; Wright, Kenneth; Alterman, Benjamin; Cirtain, Jonathan; Bookbinder, Jay; Korreck, Kelly; Stevens, Michael; Schneider, Todd;

Testing the Solar Probe Cup, an Instrument Designed to Touch the Sun

NASA Technical Reports Server (NTRS)

Whittlesey, Phyllis L.; Case, Anthony W.; Kasper, Justin Christophe; Wright, Kenneth H., Jr.; Alterman, Ben; Cirtain, Jonathan W.; Bookbinder, Jay; Korreck, Kelly E.; Stevens, Michael Louis

2014-01-01

Solar Probe Plus will be the first, fastest, and closest mission to the sun, providing the first direct sampling of the sub-Alfvenic corona. The Solar Probe Cup (SPC) is a unique re-imagining of the traditional Faraday Cup design and materials for immersion in this high temperature environment. Sending an instrument of this type into a never-seen particle environment requires extensive characterization prior to launch to establish sufficient measurement accuracy and instrument response. To reach this end, a slew of tests for allowing SPC to see ranges of appropriate ions and electrons, as well as a facility that reproduces solar photon spectra and fluxes for this mission. Having already tested the SPC at flight like temperatures with no significant modification of the noise floor, we recently completed a round of particle testing to see if the deviations in Faraday Cup design fundamentally change the operation of the instrument. Results and implications from these tests will be presented, as well as performance comparisons to cousin instruments such as those on the WIND spacecraft.

A Comparative Analysis of the Sugar Phosphate Cyclase Superfamily Involved in Primary and Secondary Metabolism

PubMed Central

Wu, Xiumei; Flatt, Patricia M.; Schlörke, Oliver; Zeeck, Axel; Dairi, Tohru

2011-01-01

Sugar Phosphate Cyclases (SPCs) catalyze the cyclization of sugar phosphates to produce a variety of cyclitol intermediates that serve as the building blocks of many primary metabolites, e.g., aromatic amino acids, and clinically relevant secondary metabolites, e.g., aminocyclitol/aminoglycoside and ansamycin antibiotics. Feeding experiments with isotopically-labeled cyclitols revealed that cetoniacytone A, a unique C7N-aminocyclitol antibiotic isolated from an insect endophytic Actinomyces sp., is derived from 2-epi-5-epi-valiolone, a product of SPC. Using heterologous probes from the 2-epi-5-epi-valiolone synthase class of SPCs, an SPC homolog gene, cetA, was isolated from the cetoniacytone producer. CetA is closely related to BE-orf9 found in the BE-40644 biosynthetic gene cluster from Actinoplanes sp. strain A40644. Recombinant expression of cetA and BE-orf9 and biochemical characterization of the gene products confirmed their function as 2-epi-5-epi-valiolone synthases. Further phylogenetic analysis of SPC sequences revealed a new clade of SPCs that may regulate the biosynthesis of a novel set of secondary metabolites. PMID:17195255

High-pressure crystal structures of an insensitive energetic crystal: 1,1-diamino-2,2-dinitroethene

DOE PAGES

Dreger, Zbigniew A.; Stash, Adam I.; Yu, Zhi -Gang; ...

2015-12-03

Understanding the insensitivity/stability of insensitive high explosive crystals requires detailed structural information at high pressures and high temperatures of interest. Synchrotron single crystal x-ray diffraction experiments were used to determine the high-pressure structures of 1,1-diamino-2,2-dinitroethene (FOX-7), a prototypical insensitive high explosive. The phase transition around 4.5 GPa was investigated and the structures were determined at 4.27 GPa (α’-phase) and 5.9 GPa (ε-phase). The α’-phase (monoclinic, P2 1/ n), structurally indistinguishable from the ambient α-phase, transforms to the new ε-phase (triclinic, P1). The most notable features of the ε-phase, compared to the α’-phase, are: formation of planar layers and flattening ofmore » molecules. Density functional theory (DFT-D2) calculations complemented the experimental results. Furthermore, the results presented here are important for understanding the molecular and crystalline attributes governing the high-pressure insensitivity/stability of insensitive high explosive crystals.« less

High-pressure crystal structures of an insensitive energetic crystal: 1,1-diamino-2,2-dinitroethene

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

Dreger, Zbigniew A.; Stash, Adam I.; Yu, Zhi -Gang

Understanding the insensitivity/stability of insensitive high explosive crystals requires detailed structural information at high pressures and high temperatures of interest. Synchrotron single crystal x-ray diffraction experiments were used to determine the high-pressure structures of 1,1-diamino-2,2-dinitroethene (FOX-7), a prototypical insensitive high explosive. The phase transition around 4.5 GPa was investigated and the structures were determined at 4.27 GPa (α’-phase) and 5.9 GPa (ε-phase). The α’-phase (monoclinic, P2 1/ n), structurally indistinguishable from the ambient α-phase, transforms to the new ε-phase (triclinic, P1). The most notable features of the ε-phase, compared to the α’-phase, are: formation of planar layers and flattening ofmore » molecules. Density functional theory (DFT-D2) calculations complemented the experimental results. Furthermore, the results presented here are important for understanding the molecular and crystalline attributes governing the high-pressure insensitivity/stability of insensitive high explosive crystals.« less

Formation of co-crystals: Kinetic and thermodynamic aspects

NASA Astrophysics Data System (ADS)

Gagnière, E.; Mangin, D.; Puel, F.; Rivoire, A.; Monnier, O.; Garcia, E.; Klein, J. P.

2009-04-01

Co-crystallisation is a recent method of great interest for the pharmaceutical industry, since pharmaceutical co-crystals represent useful materials for drug products. In this study, an active pharmaceutical ingredient (carbamazepine (CBZ)) co-crystallized with a vitamin (nicotinamide (NCT)) was chosen as a model substance. This work was focused on the construction of a phase diagram for the system CBZ/NCT, split in six domains for kinetic reasons (the different solid phases which might appear during the crystallisation) and in four domains according to thermodynamic aspects (the stable final phase obtained). Although co-crystals are not ionic compounds, the supersaturation of co-crystals can be evaluated by considering the solubility product. Batch crystallisation operations were carried out in a stirred vessel equipped with an in situ video probe. This latter device was a powerful analysis tool to monitor the CBZ/NCT co-crystals and single CBZ crystals since these two crystalline phases grown in ethanol exhibited needle and platelet habits. As concerns kinetics, the different solid phases which might appear during the experiments were observed and competed against each others. In accordance with thermodynamics, the stable solid form was obtained at the end of the operation. Finally some preliminary results indicate that the nucleation of co-crystals may be favoured by the presence of CBZ crystals. Epitaxial relationships between CBZ/NCT co-crystals and CBZ crystals were suspected.

Crystallization, X-ray diffraction analysis and SIRAS/molecular-replacenent phasing of three crystal forms of Anabaena sensory rhodopsin transducer

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

Vogeley, Lutz; Luecke, Hartmut, E-mail: hudel@uci.edu

2006-04-01

Crystals of Anabaena sensory rhodopsin transducer, the transducer for the cyanobacterial photosensor Anabaena sensory rhodopsin, obtained in the space groups P4, C2 and P2{sub 1}2{sub 1}2{sub 1} diffract to 1.8, 2.1 and 2.0 Å, respectively. Phases for these crystal forms were obtained by SIRAS phasing using an iodide quick-soak derivative (P4) and molecular replacement (C2 and P2{sub 1}2{sub 1}2{sub 1}). Anabaena sensory rhodopsin transducer (ASRT) is a 14.7 kDa soluble signaling protein associated with the membrane-embedded light receptor Anabaena sensory rhodopsin (ASR) from Anabaena sp., a freshwater cyanobacterium. Crystals of ASRT were obtained in three different space groups, P4, C2more » and P2{sub 1}2{sub 1}2{sub 1}, which diffract to 1.8, 2.1 and 2.0 Å, respectively. Phases for one of these crystal forms (P4) were obtained by SIRAS phasing using an iodide quick-soak derivative and a partial model was built. Phases for the remaining crystal forms were obtained by molecular replacement using the partial model from the P4 crystal form.« less

Ice Nuclei measurements across Europe within BACCHUS

NASA Astrophysics Data System (ADS)

Rinaldi, Matteo; Nicosia, Alessia; Santachiara, Gianni; Decesari, Stefano; Paglione, Marco; Sandrini, Silvia; Gilardoni, Stefania; Cristofanelli, Paolo; Marinoni, Angela; Bonasoni, Paolo; Facchini, Maria Cristina; Belosi, Franco

2017-04-01

Ice in clouds is formed prevalently via heterogeneous nucleation involving aerosol particles known as ice nucleating particles (INPs). A wide variety of measurement techniques have been developed for detecting INPs in different activation modes. In this study, concentrations of INPs were detected by the membrane filter technique, using a dynamic filter processing chamber (DFPC). Experimental campaigns were carried out in the framework of BACCHUS (FP7-603445) and Air-Sea Lab (CNR) projects in different locations and seasons: San Pietro Capofiume (SPC), a rural background site in the Po Valley (Italy) (winter campaign: SPC1; summer campaign: SPC2); Mace Head (MH), a North Atlantic coastal site in Western Ireland, during August 2015, with the aim of investigating the dominant sources of INP in the North Atlantic Marine Boundary Layer; Monte Cimone (MC) Global Atmospheric Watch (GAW) station, a high altitude site (2165 m asl) in the Apennine Mounts facing the Po Valley (summer campaign: MC1; winter campaign: MC2) and Capogranitola (CG) a coastal site facing the Strait of Sicily, representative of the Mediterranean background, in April 2016. Samples were collected using a parallel PM1 - PM10 sampling. The concentration of INP was detected at different temperatures and supersaturations with respect to ice and water (Santachiara et al., 2010). Measurements with the DFPC below water saturation (Sw< 1) are considered representative of deposition nucleation, while above water saturation (Sw ≥ 1) of deposition and condensation-freezing. In detail, measurements were carried out at -22°C (MH and CG) and -18°C (MH, MC and CG), with Sw = 0.96 and Sw = 1.02. The lower average concentration in the PM10 fraction was measured at MH (10 m-3) and the highest at SPC (310 m-3, during SPC1). Comparison of INP in the PM1 and PM10 size ranges shows the importance of measuring the freezing activity of particles larger than one micrometer (Mason et al., 2016). Saharan dust transport episodes were observed during the campaigns SPC2 and MC1. These episodes are characterized by increased INP concentration in the PM10 size range, particularly at Sw=1.02, and enhanced total super-micrometer particle concentration. However, observations show a decrease of the activated fraction during these events. This could depend on aging processes during long range transport of mineral dust, e.g. coating with sulphate, sea salt, etc. (Levin et al., 2005). Levin, Z., et al (2005) J. Geophys. Res., D20202. Mason, R.H., et al (2016) Atmos. Chem. Phys., 16, 1637-1651. Santachiara, G., et al (2010) Atmospheric Research 96, 266-272.

A Comparison of the Effect of Two Power Toothbrushes on the Gingival Health and Plaque Status of Subjects with Moderate Gingivitis.

PubMed

Starke, Michelle; Delaurenti, Marcia; Ward, Marilyn; Souza, Sonia; Milleman, Kimberly R; Milleman, Jeffery L

2017-03-01

To compare the effect of the Philips Sonicare DiamondClean plus Premium plaque control brush head with the Oral-B 7000 plus CrossAction brush head on gingivitis and supragingival plaque reduction following a 42-day period of home use. This was a randomized, parallel, examiner-blind, prospective clinical trial conducted on generally healthy subjects. Eligible subjects met the following eligibility criteria: age 18-65, non-smoker, routine manual toothbrush user, ≥ 50 sites of gingival bleeding per the Gingival Bleeding Index (GBI), and ≥ 1.8 plaque score per the Modified Plaque Index (MPI), assessed three to six hours following the last oral hygiene procedure. Eligible subjects were enrolled in the study and randomly assigned to use either a Philips Sonicare DiamondClean with Premium plaque control brush head power toothbrush (SPC) or an Oral-B® 7000 with CrossAction™ brush head power toothbrush (OCA), for twice daily home use over a period of 42 days. All subjects were dispensed a standard fluoride-containing dentifrice and both toothbrushes were to be used in their respective Deep Clean modes. Safety and efficacy evaluations were performed at 14 and 42 days following Baseline. Two-hundred eighty-four subjects completed this trial (142 subjects per treatment group). Least squares mean (95% CI) estimates for reduction and percent reduction of gingivitis per Modified Gingival Index (MGI) following 42 days of product use for the SPC group were 1.17 (1.10, 1.24) and 45.68% (42.95%, 48.40%); for the OCA group they were 0.69 (0.62, 0.76) and 26.83% (24.10%, 29.56%). The mean difference (95% CI) between the two treatment groups was 0.48 (0.38, 0.58) and 18.85% (14.99%, 22.70%) for reduction and percent reduction, respectively. The lower limit of the 95% CI for the difference in Overall score between the two treatment groups was greater than the predefined non-inferiority margin (i.e., -0.10 or -5%); therefore SPC was declared non-inferior to OCA. In addition, since the 95% CI for the difference did not include zero, SPC was declared superior to OCA in the reduction of gingivitis per MGI at Day 42 (p-value < 0.0001). Similarly, for MGI at Day 14 and for GBI and MPI at Day 14 and Day 42, significantly larger reductions were observed for SPC compared to OCA (p-value < 0.0001). Philips Sonicare DiamondClean with Premium plaque control brush head (SPC) was statistically superior to the Oral-B 7000 with CrossAction brush head (OCA) in reducing gingival inflammation, gingival bleeding, and supragingival plaque following 14 and 42 days of home use. Both products were safe for use.

The stability of a crystal with diamond structure for patchy particles with tetrahedral symmetry.

PubMed

Noya, Eva G; Vega, Carlos; Doye, Jonathan P K; Louis, Ard A

2010-06-21

The phase diagram of model anisotropic particles with four attractive patches in a tetrahedral arrangement has been computed at two different values of the range of the potential, with the aim of investigating the conditions under which a diamond crystal can be formed. We find that the diamond phase is never stable for our longer-ranged potential. At low temperatures and pressures, the fluid freezes into a body-centered-cubic solid that can be viewed as two interpenetrating diamond lattices with a weak interaction between the two sublattices. Upon compression, an orientationally ordered face-centered-cubic crystal becomes more stable than the body-centered-cubic crystal, and at higher temperatures, a plastic face-centered-cubic phase is stabilized by the increased entropy due to orientational disorder. A similar phase diagram is found for the shorter-ranged potential, but at low temperatures and pressures, we also find a region over which the diamond phase is thermodynamically favored over the body-centered-cubic phase. The higher vibrational entropy of the diamond structure with respect to the body-centered-cubic solid explains why it is stable even though the enthalpy of the latter phase is lower. Some preliminary studies on the growth of the diamond structure starting from a crystal seed were performed. Even though the diamond phase is never thermodynamically stable for the longer-ranged model, direct coexistence simulations of the interface between the fluid and the body-centered-cubic crystal and between the fluid and the diamond crystal show that at sufficiently low pressures, it is quite probable that in both cases the solid grows into a diamond crystal, albeit involving some defects. These results highlight the importance of kinetic effects in the formation of diamond crystals in systems of patchy particles.

Controlled In Meso Phase Crystallization – A Method for the Structural Investigation of Membrane Proteins

PubMed Central

Kubicek, Jan; Schlesinger, Ramona; Baeken, Christian; Büldt, Georg; Schäfer, Frank; Labahn, Jörg

2012-01-01

We investigated in meso crystallization of membrane proteins to develop a fast screening technology which combines features of the well established classical vapor diffusion experiment with the batch meso phase crystallization, but without premixing of protein and monoolein. It inherits the advantages of both methods, namely (i) the stabilization of membrane proteins in the meso phase, (ii) the control of hydration level and additive concentration by vapor diffusion. The new technology (iii) significantly simplifies in meso crystallization experiments and allows the use of standard liquid handling robots suitable for 96 well formats. CIMP crystallization furthermore allows (iv) direct monitoring of phase transformation and crystallization events. Bacteriorhodopsin (BR) crystals of high quality and diffraction up to 1.3 Å resolution have been obtained in this approach. CIMP and the developed consumables and protocols have been successfully applied to obtain crystals of sensory rhodopsin II (SRII) from Halobacterium salinarum for the first time. PMID:22536388

Understanding the structure of chocolate

NASA Astrophysics Data System (ADS)

Schenk, H.; Peschar, R.

2004-10-01

Crystallization of cocoa-butter in the β phase from the melt under static conditions is only possible using the memory effect of cocoa-butter. Under all other conditions polymorphs with lower melting temperatures develop, whereas the β phase is the preferred one in chocolate. SAXS experiments proved 1,3-distearoyl-2-oleoylglycerol seeds with triple chain-length packing initiate the β-crystallization. Models for the different phases may be based on the crystal structure determinations of triacylglycerols. A new, patented, way of chocolate making is in development in which the traditional tempering process is replaced by another pre-crystallization process. The process is based on the use of seed crystals in the liquid phase and driven by a feedback system.

An Investigation into the Polymorphism and Crystallization of Levetiracetam and the Stability of its Solid Form.

PubMed

Xu, Kailin; Xiong, Xinnuo; Guo, Liuqi; Wang, Lili; Li, Shanshan; Tang, Peixiao; Yan, Jin; Wu, Di; Li, Hui

2015-12-01

Levetiracetam (LEV) crystals were prepared using different solvents at different temperatures. The LEV crystals were systematically characterized by X-ray powder diffraction (XRPD) and morphological analysis. The results indicated that many kinds of crystal habits exist in a solid form of LEV. To investigate the effects of LEV concentration, crystallization temperature, and crystallization type on crystallization and solid phase transformation of LEV, multiple methods were performed for LEV aqueous solution to determine if a new solid form exists in solid-state LEV. However, XRPD data demonstrate that the LEV solid forms possess same spatial arrangements that are similar to the original solid form. This result indicates that the LEV concentration, crystallization temperature, and crystallization type in aqueous solution have no influence on the crystallization and solid phase transformation of LEV. Moreover, crystallization by sublimation, melt cooling, and quench cooling, as well as mechanical effect, did not result in the formation of new LEV solid state. During melt cooling, the transformation of solid form LEV is a direct process from melting amorphous phase to the original LEV crystal phase, and the conversion rate is very quick. In addition, stability investigation manifested that LEV solid state is very stable under various conditions. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

Modelling Assisted Design and Synthesis of Highly Porous Materials for Chemical Adsorbents

DTIC Science & Technology

2010-10-01

two phases of crystal, a monoclinic phase within the solution, and after removal from solution a trigonal phase is obtained. The single crystal...days. Single crystal X-ray data showed there existed a monoclinic phase within the solution that, upon removal from solution, rapidly converted to a... monoclinic to trigonal upon desolvation, as the new peak which has emerged matches the simulated PXRD of the trigonal phase. Also, as the sample is

The role of superheating in the formation of Glass Mountain obsidians (Long Valley, CA) inferred through crystallization of sanidine

NASA Astrophysics Data System (ADS)

Waters, Laura E.; Andrews, Benjamin J.

2016-10-01

The Glass Mountain obsidians (Long Valley, CA) are crystal poor (<8 vol%) and highly evolved (high SiO2, low Sr), and therefore, their formation required extremely efficient separation of melts from a crystal-rich source. A petrologic and experimental investigation of the mineral phases in Glass Mountain lavas identifies conditions under which phenocrysts grew and the driving mechanism for crystallization, which places constraints on the possible processes that generated the obsidians. The obsidian in this study (GM-11) is saturated in nine phases (sanidine + quartz + plagioclase + titanomagnetite + ilmenite + zircon + apatite + allanite + biotite), and results of high-resolution SEM compositional mapping and electron microprobe analysis reveal that individual sanidine crystals are normally zoned and span a range of compositions (Or40-78). Sanidines have a "granophyric" texture, characterized by intergrowths of quartz and sanidine. Mineral phases in the natural sample are compared to H2O-saturated phase equilibrium experiments conducted in cold-seal pressure vessels, over a range of conditions (700-850 °C; 75-225 MPa), and all are found to be plausible phenocrysts. Comparison of sanidine compositions from the natural sample with those grown in phase equilibrium experiments demonstrates that sanidine in the natural sample occurs in a reduced abundance. Further comparison with phase equilibrium experiments suggests that sanidine compositions track progressive loss of dissolved melt water (±cooling), suggesting that crystallization in the natural obsidian was driven predominantly by degassing resulting from decompression. It is paradoxical that an effusively (slowly) erupted lava should contain multiple phenocryst phases, including sanidine crystals that span a range of compositions with granophyric textures, and yet remain so crystal poor. To resolve this paradox, it is necessary that the solidification mechanism (degassing or cooling) that produced the sanidine crystals (and other mineral phases) must have an associated kinetic effect(s) that efficiently hinders crystal nucleation and growth. Decompression experiments conducted in this study and from the literature collectively demonstrate that the simplest way to inhibit nucleation during degassing-induced crystallization is to initiate degassing ± cooling from superliquidus conditions, and therefore, the Glass Mountain obsidians were superheated prior to crystallization.

Crystallization of spray-dried lactose/protein mixtures in humid air

NASA Astrophysics Data System (ADS)

Shawqi Barham, A.; Kamrul Haque, Md.; Roos, Yrjö H.; Kieran Hodnett, B.

2006-10-01

An in situ crystallization technique with X-ray diffraction analysis complemented by ex situ scanning electron microscopy and chromatographic analysis of the α/( α+ β) solid-state anomeric ratios has been developed to study the crystallization of lactose/protein mixtures in humid air. This technique was used to determine changes in phase composition and morphology during crystallization. Following an induction period during which water is sorbed, crystallization is rapid and the predominant phase observed using the in situ method in spray-dried lactose/sodium-caseinate, albumin and gelatin is α-lactose monohydrate. However, in the case of spray-dried lactose/whey protein isolate (WPI) the predominant phase that appears is the α/ β mixed phase with smaller amounts of α-lactose monohydrate. With pure lactose the α/ β mixed phase appears as a transient shortly after the onset of crystallization and α-lactose monohydrate and β-lactose both appear as stable crystalline phases at longer times. Another transient phase with 2 θ=12.2°, 20.7° and 21.8° was observed in spray-dried lactose/albumin. This phase decomposed as α-lactose monohydrate developed. Three phases seem to persist in the case of spray-dried lactose/gelatin, namely the phase with peaks at 2 θ=12.2°, 20.7° and 21.8°, α-lactose monohydrate and β-lactose for the duration of the in situ experiment.

Application Of Empirical Phase Diagrams For Multidimensional Data Visualization Of High Throughput Microbatch Crystallization Experiments.

PubMed

Klijn, Marieke E; Hubbuch, Jürgen

2018-04-27

Protein phase diagrams are a tool to investigate cause and consequence of solution conditions on protein phase behavior. The effects are scored according to aggregation morphologies such as crystals or amorphous precipitates. Solution conditions affect morphological features, such as crystal size, as well as kinetic features, such as crystal growth time. Common used data visualization techniques include individual line graphs or symbols-based phase diagrams. These techniques have limitations in terms of handling large datasets, comprehensiveness or completeness. To eliminate these limitations, morphological and kinetic features obtained from crystallization images generated with high throughput microbatch experiments have been visualized with radar charts in combination with the empirical phase diagram (EPD) method. Morphological features (crystal size, shape, and number, as well as precipitate size) and kinetic features (crystal and precipitate onset and growth time) are extracted for 768 solutions with varying chicken egg white lysozyme concentration, salt type, ionic strength and pH. Image-based aggregation morphology and kinetic features were compiled into a single and easily interpretable figure, thereby showing that the EPD method can support high throughput crystallization experiments in its data amount as well as its data complexity. Copyright © 2018. Published by Elsevier Inc.

Surface Protonation at the Rutile (110) Interface: Explicit Incorporation of Solvation Structure within the Refined MUSIC Model Framework

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

Machesky, Michael L.; Predota, M.; Wesolowski, David J

The detailed solvation structure at the (110) surface of rutile ({alpha}-TiO{sub 2}) in contact with bulk liquid water has been obtained primarily from experimentally verified classical molecular dynamics (CMD) simulations of the ab initio-optimized surface in contact with SPC/E water. The results are used to explicitly quantify H-bonding interactions, which are then used within the refined MUSIC model framework to predict surface oxygen protonation constants. Quantum mechanical molecular dynamics (QMD) simulations in the presence of freely dissociable water molecules produced H-bond distributions around deprotonated surface oxygens very similar to those obtained by CMD with nondissociable SPC/E water, thereby confirming thatmore » the less computationally intensive CMD simulations provide accurate H-bond information. Utilizing this H-bond information within the refined MUSIC model, along with manually adjusted Ti-O surface bond lengths that are nonetheless within 0.05 {angstrom} of those obtained from static density functional theory (DFT) calculations and measured in X-ray reflectivity experiments (as well as bulk crystal values), give surface protonation constants that result in a calculated zero net proton charge pH value (pHznpc) at 25 C that agrees quantitatively with the experimentally determined value (5.4 {+-} 0.2) for a specific rutile powder dominated by the (110) crystal face. Moreover, the predicted pH{sub znpc} values agree to within 0.1 pH unit with those measured at all temperatures between 10 and 250 C. A slightly smaller manual adjustment of the DFT-derived Ti-O surface bond lengths was sufficient to bring the predicted pH{sub znpc} value of the rutile (110) surface at 25 C into quantitative agreement with the experimental value (4.8 {+-} 0.3) obtained from a polished and annealed rutile (110) single crystal surface in contact with dilute sodium nitrate solutions using second harmonic generation (SHG) intensity measurements as a function of ionic strength. Additionally, the H-bond interactions between protolyzable surface oxygen groups and water were found to be stronger than those between bulk water molecules at all temperatures investigated in our CMD simulations (25, 150 and 250 C). Comparison with the protonation scheme previously determined for the (110) surface of isostructural cassiterite ({alpha}-SnO{sub 2}) reveals that the greater extent of H-bonding on the latter surface, and in particular between water and the terminal hydroxyl group (Sn-OH) results in the predicted protonation constant for that group being lower than for the bridged oxygen (Sn-O-Sn), while the reverse is true for the rutile (110) surface. These results demonstrate the importance of H-bond structure in dictating surface protonation behavior, and that explicit use of this solvation structure within the refined MUSIC model framework results in predicted surface protonation constants that are also consistent with a variety of other experimental and computational data.« less

Surface protonation at the rutile (110) interface: explicit incorporation of solvation structure within the refined MUSIC model framework.

PubMed

Machesky, Michael L; Predota, Milan; Wesolowski, David J; Vlcek, Lukas; Cummings, Peter T; Rosenqvist, Jörgen; Ridley, Moira K; Kubicki, James D; Bandura, Andrei V; Kumar, Nitin; Sofo, Jorge O

2008-11-04

The detailed solvation structure at the (110) surface of rutile (alpha-TiO2) in contact with bulk liquid water has been obtained primarily from experimentally verified classical molecular dynamics (CMD) simulations of the ab initio-optimized surface in contact with SPC/E water. The results are used to explicitly quantify H-bonding interactions, which are then used within the refined MUSIC model framework to predict surface oxygen protonation constants. Quantum mechanical molecular dynamics (QMD) simulations in the presence of freely dissociable water molecules produced H-bond distributions around deprotonated surface oxygens very similar to those obtained by CMD with nondissociable SPC/E water, thereby confirming that the less computationally intensive CMD simulations provide accurate H-bond information. Utilizing this H-bond information within the refined MUSIC model, along with manually adjusted Ti-O surface bond lengths that are nonetheless within 0.05 A of those obtained from static density functional theory (DFT) calculations and measured in X-ray reflectivity experiments (as well as bulk crystal values), give surface protonation constants that result in a calculated zero net proton charge pH value (pHznpc) at 25 degrees C that agrees quantitatively with the experimentally determined value (5.4+/-0.2) for a specific rutile powder dominated by the (110) crystal face. Moreover, the predicted pHznpc values agree to within 0.1 pH unit with those measured at all temperatures between 10 and 250 degrees C. A slightly smaller manual adjustment of the DFT-derived Ti-O surface bond lengths was sufficient to bring the predicted pHznpcvalue of the rutile (110) surface at 25 degrees C into quantitative agreement with the experimental value (4.8+/-0.3) obtained from a polished and annealed rutile (110) single crystal surface in contact with dilute sodium nitrate solutions using second harmonic generation (SHG) intensity measurements as a function of ionic strength. Additionally, the H-bond interactions between protolyzable surface oxygen groups and water were found to be stronger than those between bulk water molecules at all temperatures investigated in our CMD simulations (25, 150 and 250 degrees C). Comparison with the protonation scheme previously determined for the (110) surface of isostructural cassiterite (alpha-SnO2) reveals that the greater extent of H-bonding on the latter surface, and in particular between water and the terminal hydroxyl group (Sn-OH) results in the predicted protonation constant for that group being lower than for the bridged oxygen (Sn-O-Sn), while the reverse is true for the rutile (110) surface. These results demonstrate the importance of H-bond structure in dictating surface protonation behavior, and that explicit use of this solvation structure within the refined MUSIC model framework results in predicted surface protonation constants that are also consistent with a variety of other experimental and computational data.

Phase-field crystal simulation facet and branch crystal growth

NASA Astrophysics Data System (ADS)

Chen, Zhi; Wang, Zhaoyang; Gu, Xinrui; Chen, Yufei; Hao, Limei; de Wit, Jos; Jin, Kexin

2018-05-01

Phase-field crystal model with one mode is introduced to describe morphological transition. The relationship between growth morphology and smooth density distribution was investigated. The results indicate that the pattern selection of dendrite growth is caused by the competition between interface energy anisotropy and interface kinetic anisotropy based on the 2D phase diagram. When the calculation time increases, the crystal grows to secondary dendrite at the dimensionless undercooling equal to - 0.4. Moreover, when noise is introduced in the growth progress, the symmetry is broken in the growth mode, and there becomes irregular fractal-like growth morphology. Furthermore, the single crystal shape develops into polycrystalline when the noise amplitude is large enough. When the dimensionless undercooling is less than - 0.3, the noise has a significant effect on the growth shape. In addition, the growth velocity of crystal near to liquid phase line is slow, while the shape far away from the liquid adapts to fast growth. Based on the simulation results, the method was proved to be effective, and it can easily obtain different crystal shapes by choosing the different points in 2D phase diagram.

Phase coexistence and domain configuration in Pb(Mg1/3Nb2/3)O3-0.34PbTiO3 single crystal revealed by synchrotron-based X-ray diffractive three-dimensional reciprocal space mapping and piezoresponse force microscopy

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

Wang, Ruixue; Xu, Han; Yang, Bin

The crystalline phases and domain configuration in the morphotropic phase boundary composition Pb(Mg1/3Nb2/3)O3-0.34PbTiO3 (PMN-0.34PT) single crystal have been investigated by synchrotronbased X-ray 3D Reciprocal Space Mapping (3D-RSM) and Piezoresponse Force Microscopy. The coexistence of tetragonal (T) and monoclinic MC phases in this PMN-0.34PT single crystal is confirmed. The affiliation of each diffraction spot in the 3D-RSM was identified with the assistance of qualitative simulation. Most importantly, the twinning structure between different domains in such a mixed phase PMN-PT crystal is firmly clarified, and the spatial distribution of different twin domains is demonstrated. In addition, the lattice parameters of T andmore » MC phases in PMN-0.34PT single crystal as well as the tilting angles of crystal lattices caused by the interfacial lattice mismatch are determined.« less

Extensional Flow-Induced Dynamic Phase Transitions in Isotactic Polypropylene.

PubMed

Ju, Jianzhu; Wang, Zhen; Su, Fengmei; Ji, Youxin; Yang, Haoran; Chang, Jiarui; Ali, Sarmad; Li, Xiangyang; Li, Liangbin

2016-09-01

With a combination of fast extension rheometer and in situ synchrotron radiation ultra-fast small- and wide-angle X-ray scattering, flow-induced crystallization (FIC) of isotactic polypropylene (iPP) is studied at temperatures below and above the melting point of α crystals (Tmα). A flow phase diagram of iPP is constructed in strain rate-temperature space, composing of melt, non-crystalline shish, α and α&β coexistence regions, based on which the kinetic and dynamic competitions among these four phases are discussed. Above Tmα , imposing strong flow reverses thermodynamic stabilities of the disordered melt and the ordered phases, leading to the occurrence of FIC of β and α crystals as a dynamic phase transition. Either increasing temperature or stain rate favors the competiveness of the metastable β over the stable α crystals, which is attributed to kinetic rate rather than thermodynamic stability. The violent competitions among four phases near the boundary of crystal-melt may frustrate crystallization and result in the non-crystalline shish winning out. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Large three-dimensional photonic crystals based on monocrystalline liquid crystal blue phases.

PubMed

Chen, Chun-Wei; Hou, Chien-Tsung; Li, Cheng-Chang; Jau, Hung-Chang; Wang, Chun-Ta; Hong, Ching-Lang; Guo, Duan-Yi; Wang, Cheng-Yu; Chiang, Sheng-Ping; Bunning, Timothy J; Khoo, Iam-Choon; Lin, Tsung-Hsien

2017-09-28

Although there have been intense efforts to fabricate large three-dimensional photonic crystals in order to realize their full potential, the technologies developed so far are still beset with various material processing and cost issues. Conventional top-down fabrications are costly and time-consuming, whereas natural self-assembly and bottom-up fabrications often result in high defect density and limited dimensions. Here we report the fabrication of extraordinarily large monocrystalline photonic crystals by controlling the self-assembly processes which occur in unique phases of liquid crystals that exhibit three-dimensional photonic-crystalline properties called liquid-crystal blue phases. In particular, we have developed a gradient-temperature technique that enables three-dimensional photonic crystals to grow to lateral dimensions of ~1 cm (~30,000 of unit cells) and thickness of ~100 μm (~ 300 unit cells). These giant single crystals exhibit extraordinarily sharp photonic bandgaps with high reflectivity, long-range periodicity in all dimensions and well-defined lattice orientation.Conventional fabrication approaches for large-size three-dimensional photonic crystals are problematic. By properly controlling the self-assembly processes, the authors report the fabrication of monocrystalline blue phase liquid crystals that exhibit three-dimensional photonic-crystalline properties.

Development of non-bonded interaction parameters between graphene and water using particle swarm optimization.

PubMed

Bejagam, Karteek K; Singh, Samrendra; Deshmukh, Sanket A

2018-05-05

New Lennard-Jones parameters have been developed to describe the interactions between atomistic model of graphene, represented by REBO potential, and five commonly used all-atom water models, namely SPC, SPC/E, SPC/Fw, SPC/Fd, and TIP3P/Fs by employing particle swarm optimization (PSO) method. These new parameters were optimized to reproduce the macroscopic contact angle of water on a graphene sheet. The calculated line tension was in the order of 10 -11 J/m for the droplets of all water models. Our molecular dynamics simulations indicate the preferential orientation of water molecules near graphene-water interface with one OH bond pointing toward the graphene surface. Detailed analysis of simulation trajectories reveals the presence of water molecules with ≤∼1, ∼2, and ∼4 hydrogen bonds at the surface of air-water interface, graphene-water interface, and bulk region of the water droplet, respectively. Presence of water molecules with ≤∼1 and ∼2 hydrogen bonds suggest the existence of water clusters of different sizes at these interfaces. The trends observed in the libration, bending, and stretching bands of the vibrational spectra are closely associated with these structural features of water. The inhomogeneity in hydrogen bond network of water at the air-water and graphene-water interface is manifested by broadening of the peaks in the libration band for water present at these interfaces. The stretching band for the molecules in water droplet shows a blue shift as compared to the pure bulk water, which conjecture the presence of weaker hydrogen bond network in a droplet. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Changes in sevoflurane plasma concentration with delivery through the oxygenator during on-pump cardiac surgery.

PubMed

Nitzschke, R; Wilgusch, J; Kersten, J F; Trepte, C J; Haas, S A; Reuter, D A; Goetz, A E; Goepfert, M S

2013-06-01

It is unclear what factors affect the uptake of sevoflurane administered through the membrane oxygenator during cardiopulmonary bypass (CPB) and whether this can be monitored via the oxygenator exhaust gas. Stable delivery of sevoflurane was administered to 30 elective cardiac surgery patients at 1.8 vol% (inspiratory) via the anaesthetic circuit and ventilator. During CPB, sevoflurane was administered in the oxygenator fresh gas supply (Compactflo Evolution™; Sorin Group, Milano, Italy). Sevoflurane plasma concentration (SPC) was measured using gas chromatography. Changes were correlated with bispectral index (BIS), patient temperature, haematocrit, plasma albumin concentration, oxygenator fresh gas flow, and the sevoflurane concentration in the oxygenator exhaust at predefined time points. The mean SPC pre-bypass was 54.9 µg ml(-1) [95% confidence interval (CI): 50.6-59.1]. SPC decreased to 43.2 µg ml(-1) (95% CI: 40.3-46.1; P<0.001) after initiation of CPB, and was lower still during rewarming and weaning from bypass, 39.4 µg ml(-1) (95% CI: 36.6-42.3; P<0.001). BIS did not exceed a value of 55. SPCs were higher during hypothermia (P<0.001) and with an increase in oxygenator fresh gas flow (P=0.015), and lower with haemodilution (P=0.027). No correlation was found between SPC and the concentration of sevoflurane in the oxygenator exhaust gas (r=-0.04; 95% CI: -0.18 to 0.09; P=0.53). The uptake of sevoflurane delivered via the membrane oxygenator during CPB seems to be affected by hypothermia, haemodilution, and changes in the oxygenator fresh gas supply flow. Measuring the concentration of sevoflurane in the exhaust from the oxygenator is not useful for monitoring sevoflurane administration during bypass.

GP perceptions of the adequacy of community-based care for patients with advanced heart failure in a UK region (NI): a qualitative study

PubMed Central

Chen, Jingwen Jessica; Gamble, Kathryn; Graham-Wisener, Lisa; McGlade, Kieran; Doherty, Jennifer; Donnelly, Patrick; Stone, Carol A

2018-01-01

Objective To assess the adequacy of community-based services available in Northern Ireland (NI) and to meet the multidimensional needs of patients living with New York Heart Association Stage III and IV heart failure (HF), as experienced and perceived by general practitioners (GP). Methods Semistructured interviews were conducted with GPs recruited via the University Department of General Practice and Northern Ireland Medical and Dental Agency. Interviews were transcribed, independently coded and analysed using a six-step thematic analysis approach. Results Twenty semistructured interviews were conducted. GPs reported managing patients in a ‘reactive rather than proactive’ way, responding only to acute medical needs, with hospital admission the default option due to lack of community-based expertise and services. Care provided by HF specialists was highly regarded but ‘access and coordination’ were lacking, related to inequity of access to Heart Failure Nursing Teams, lack of access to specialist advice and inadequate handover of information to GPs. Conversations regarding current and future care needs and preferences were important, but GPs described ‘neglecting conversations with the patient’, due to time constraints, prognostic uncertainty and fear of causing distress. They expressed the view that ‘specialist palliative care (SPC) is only a credible option in end stages’ related to limited understanding of the scope of SPC, a perception that timing of referral must depend on prognosis and concern that SPC services are cancer-focused. Conclusions Despite the extensive body of research which evidences the unmet multidimensional needs of patients with advanced HF, and more recent evidence for the effectiveness of integrated SPC in improving quality of life for patients with HF, health and social care services within NI have not adapted to assess and meet these needs. PMID:29632677

Clinical features and prognostic factors in patients with head and neck cancer: Results from a multicentric study.

PubMed

Leoncini, Emanuele; Vukovic, Vladimir; Cadoni, Gabriella; Pastorino, Roberta; Arzani, Dario; Bosetti, Cristina; Canova, Cristina; Garavello, Werner; La Vecchia, Carlo; Maule, Milena; Petrelli, Livia; Pira, Enrico; Polesel, Jerry; Richiardi, Lorenzo; Serraino, Diego; Simonato, Lorenzo; Ricciardi, Walter; Boccia, Stefania

2015-06-01

The purpose of this study is to evaluate whether demographics, lifestyle habits, clinical data and alcohol dehydrogenase polymorphisms rs1229984 and rs1573496 associated with first primary head and neck (HNC) are associated with overall survival, recurrence, and second primary cancer (SPC). We conducted a follow-up study in five centres including 801 cases. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated for overall survival, recurrence and SPC. Five-years overall survival was 62% for HNC cases, 55% for oral cavity, 53% for oropharynx, 41% for hypopharynx, and 71% for larynx. Predictors of survival were older ages (HR=1.18 for 5 years increase; CI: 1.07-1.30), higher tumour stage (HR=4.16; CI: 2.49-6.96), and high alcohol consumption (HR=3.93; CI: 1.79-8.63). A combined therapy (HR=3.29; CI: 1.18-9.13) was associated with a worst prognosis for oral cavity cancer. The only predictor was higher tumour stage (HR=2.25; CI: 1.26-4.03) for recurrence, and duration of smoking (HR=1.91; CI: 1.00-3.68) for SPC. ADH1B rs1229984 polymorphism HRs for HNC and oesophageal cancer death and for alcohol related cancer death were 0.67 (95% CI: 0.42-1.08), and 0.64 (95% CI: 0.40-1.03), respectively. The survival expectation differs among HNC sites. Increasing age and stage, and high alcohol consumption were unfavourable predictors of HNC survival overall. Duration of tobacco consumption before the first primary tumour was a risk factor for SPC. Copyright © 2015 Elsevier Ltd. All rights reserved.

The role of external drains and peritoneal conduits in the treatment of recurrent chronic subdural hematoma.

PubMed

Santarius, Thomas; Qureshi, Hammad U; Sivakumaran, Ram; Kirkpatrick, Peter J; Kirollos, Ramez W; Hutchinson, Peter J

2010-06-01

A considerable body of evidence supporting the use of external drainage after evacuation of primary chronic subdural hematoma (CSDH) exists in the literature. However, no systematic study of the value of postoperative drainage in the treatment of recurrent CSDH has been published. The aim of the study was to investigate external drains and subdural-to-peritoneal conduit in the treatment of recurrent CSDH. A retrospective review of cases of CSDH treated in our institution between October 2002 and October 2006 was conducted. During the study period, 408 patients had burr hole evacuation. Sixty-four patients (15.9%) had treatment for recurrence. One patient had craniotomy, and the remaining 63 had another burr hole evacuation: 36 without placement of a drain (BHO), 14 with external drainage (SED), and 13 with placement of subdural-peritoneal catheter (SPC). Fifteen patients (24%) developed a secondary recurrence requiring a third drainage procedure. Postoperative drainage (SED or SPC) was associated with a significantly lower secondary recurrence rate when compared to BHO: 3/27 (11%) versus 12/36 (33%) (χ(2), P=.040). There was no significant difference in recurrence rates between SED and SPC. Postoperative complications included acute subdural hematoma (2), subdural empyema (2), brain edema (2), pneumonia (3), and in-hospital death (2). None of the complications was associated with the use of a specific technique. The results indicate that, as in the treatment of primary CSDHs, the use of drain (SED or SPC) with burr hole evacuation is safe and is associated with lower recurrence rate. Further investigation is needed to clarify the indications of currently available surgical techniques in the treatment of recurrent CSDH. Copyright © 2010 Elsevier Inc. All rights reserved.

PEG-lipid-PLGA hybrid nanoparticles loaded with berberine-phospholipid complex to facilitate the oral delivery efficiency.

PubMed

Yu, Fei; Ao, Mingtao; Zheng, Xiao; Li, Nini; Xia, Junjie; Li, Yang; Li, Donghui; Hou, Zhenqing; Qi, Zhongquan; Chen, Xiao Dong

2017-11-01

The natural product berberine (BBR), present in various plants, arouses great interests because of its numerous pharmacological effects. However, the further development and application of BBR had been hampered by its poor oral bioavailability. In this work, we report on polymer-lipid hybrid nanoparticles (PEG-lipid-PLGA NPs) loaded with BBR phospholipid complex using a solvent evaporation method for enhancing the oral BBR efficiency. The advantage of this new drug delivery system is that the BBR-soybean phosphatidylcholine complex (BBR-SPC) could be used to enhance the liposolubility of BBR and improve the affinity with the biodegradable polymer to increase the drug-loading capacity and controlled/sustained release. The entrapment efficiency of the PEG-lipid-PLGA NPs/BBR-SPC was observed to approach approximately 89% which is more than 2.4 times compared with that of the PEG-lipid-PLGA NPs/BBR. To the best of our knowledge, this is the first report on using polymer material for effective encapsulation of BBR to improve its oral bioavailability. The prepared BBR delivery systems demonstrated a uniform spherical shape, a well-dispersed core-shell structure and a small particle size (149.6 ± 5.1 nm). The crystallographic and thermal analysis has indicated that the BBR dispersed in the PEG-lipid-PLGA NPs matrix is in an amorphous form. More importantly, the enhancement in the oral relative bioavailability of the PEG-lipid-PLGA NPs/BBR-SPC was ∼343% compared with that of BBR. These positive results demonstrated that PEG-lipid-PLGA NPs/BBR-SPC may have the potential for facilitating the oral drug delivery of BBR.

The α' subunit of β-conglycinin and the A1-5 subunits of glycinin are not essential for many hypolipidemic actions of dietary soy proteins in rats.

PubMed

Chen, Qixuan; Wood, Carla; Gagnon, Christine; Cober, Elroy R; Frégeau-Reid, Judith A; Gleddie, Stephen; Xiao, Chao Wu

2014-08-01

This study examined the effects of dietary soy protein (SP) lacking different storage protein subunits and isoflavones (ISF) on the abdominal fat, blood lipids, thyroid hormones, and enzymatic activities in rats. Weanling Sprague-Dawley rats (8 males and 8 females/group) were fed diets containing either 20 % casein without or with supplemental isoflavones or alcohol-washed SP isolate or SP concentrates (SPC) prepared from 6 different soy bean lines for 8 weeks. Feeding of diets containing SPC regardless of their subunit compositions significantly lowered relative liver weights, blood total, free, and LDL cholesterol in both genders (P < 0.05) and also reduced serum free fatty acids (FFA) and abdominal fat in females (P < 0.05) compared to the casein or casein + ISF diets. Dietary SPC significantly elevated the plasma free triiodothyronine (T3) in both genders and total T3 in females compared to the casein diet (P < 0.05). The SPC lacking β-conglycinin α' and either the glycinin A1-3 or A1-5 subunits increased total T3 in males and reduced plasma enzymatic activities of creatine kinase and lactate dehydrogenase compared to casein or casein + ISF diet (P < 0.05). Soy isoflavones were mainly responsible for the hypocholesterolemic effects and increased plasma free T3, whereas reduction in FFA, abdominal fat, liver weight and increased plasma total T3 were the effects of the soy proteins. Neither the α' subunit of β-conglycinin nor the A1-5 subunits of glycinin are essential for the hypolipidemic properties of soy proteins.

Plant Products Affect Growth and Digestive Efficiency of Cultured Florida Pompano (Trachinotus carolinus) Fed Compounded Diets

PubMed Central

Lech, Gregory P.; Reigh, Robert C.

2012-01-01

Costs of compounded diets containing fish meal as a primary protein source can be expected to rise as fish meal prices increase in response to static supply and growing demand. Alternatives to fish meal are needed to reduce production costs in many aquaculture enterprises. Some plant proteins are potential replacements for fish meal because of their amino acid composition, lower cost and wide availability. In this study, we measured utilization of soybean meal (SBM) and soy protein concentrate (SPC) by Florida pompano fed compounded diets, to determine the efficacy of these products as fish meal replacements. We also calculated apparent digestibility coefficients (ADCs) for canola meal (CM), corn gluten meal (CGM), and distillers dried grains with solubles (DDGS), following typical methods for digestibility trials. Juvenile Florida pompano were fed fish-meal-free diets containing graded levels of SBM and SPC, and weight gain was compared to a control diet that contained SBM, SPC, and fish meal. Fish fed diets that contained 25–30 percent SBM in combination with 43–39 percent SPC had weight gain equivalent to fish fed the control diet with fish meal, while weight gain of fish fed other soy combinations was significantly less than that of the control group. Apparent crude protein digestibility of CGM was significantly higher than that of DDGS but not significantly different from CM. Apparent energy digestibility of DDGS was significantly lower than CGM but significantly higher than CM. Findings suggested that composition of the reference diet used in a digestibility trial affects the values of calculated ADCs, in addition to the chemical and physical attributes of the test ingredient. PMID:22536344

Transcranial direct current stimulation versus user training on improving online myoelectric control for amputees

NASA Astrophysics Data System (ADS)

Pan, Lizhi; Zhang, Dingguo; Jiang, Ning; Sheng, Xinjun; Zhu, Xiangyang

2017-08-01

Objective. Transcranial direct current stimulation (tDCS) and user training (UT) are two types of methods to improve myoelectric control performance for amputees. In this study, we compared the independent effect between tDCS and UT, and investigated the combined effect of tDCS and UT. Approach. An online paradigm of simultaneous and proportional control (SPC) based on electromyography (EMG) was adopted. The proposed experiments were conducted on six naïve unilateral trans-radial amputees. The subjects each received three types of 20 min interventions: active tDCS with motor training (tDCS  +  UT), active tDCS with quiet sitting (tDCS), and sham tDCS with motor training (UT). The interventions were applied at one week intervals in a randomized order. The subjects performed online control of a feedback arrow with two degrees of freedom (DoFs) to accomplish target reaching motor tasks in pre-sessions and post-sessions. We compared the performance, measured by completion rate, completion time, and efficiency coefficient, between pre-sessions and post-sessions. Main results. The results showed that the intervention tDCS  +  UT and tDCS significantly improved the online SPC performance (i.e. improved the completion rate; reduced the completion time; and improved the efficiency coefficient), while intervention UT did not significantly change the performance. The results also showed that the online SPC performance after intervention tDCS  +  UT and tDCS was not significantly different, but both were significantly better than that after intervention UT. Significance. tDCS could be an effective intervention to improve the online SPC performance in a short time.

Description of Leifsonia kafniensis sp. nov. and Leifsonia antarctica sp. nov.

PubMed

Pindi, Pavan Kumar; Kishore, K Hara; Reddy, G S N; Shivaji, S

2009-06-01

Strains KFC-22(T) and SPC-20(T) are yellow-pigmented, Gram-positive, aerobic, non-motile, rod-shaped bacteria that were isolated from a soil sample near the Kafni glacier in the Himalayan mountain ranges in India, and from a spade core sediment sample from the Antarctic Ocean at Larsemann Hill, respectively. In both cases, the cell-wall peptidoglycan contained 2,4-diaminobutyric acid as the diamino acid, anteiso-C(15 : 0), anteiso-C(17 : 0) and iso-C(16 : 0) were the predominant fatty acids and MK-11 was the major isoprenoid quinone in the cell membrane. On the basis of the above-mentioned characteristics, both strains can be assigned to the genus Leifsonia. The strains share 16S rRNA gene sequence similarity of 97.7 % and DNA relatedness of only 10 %, indicating that they represent different species. A blast analysis indicated that Leifsonia pindariensis PON10(T) was the closest phylogenetic neighbour of strains SPC-20(T) and KFC-22(T), showing 16S rRNA gene sequence similarities of 97.3 and 97.7 %, respectively. However, at the whole-genome level, strains KFC-22(T) and SPC-20(T) shared 42 and 11 % DNA-DNA relatedness, respectively, with L. pindariensis PON10(T). In addition, both strains exhibited several phenotypic differences with respect to L. pindariensis PON10(T). Thus, on the basis of the differences that the two strains exhibited with respect to L. pindariensis, both were identified as representing novel species of the genus Leifsonia, for which the names Leifsonia kafniensis sp. nov. (type strain KFC-22(T) =NCCB 100216(T) =LMG 24362(T)) and Leifsonia antarctica sp. nov. (type strain SPC-20(T) =NCCB 100227(T) =LMG 24541(T)) are proposed.

Suprapubic cystostomy for neurogenic bladder using Lowsley retractor method: a procedure revisited.

PubMed

Edokpolo, Leonard U; Foster, Harris E

2011-11-01

To report our experience with the Lowsley retractor method for suprapubic cystostomy (SPC) in patients with neurogenic bladder (NGB). A retrospective study was performed of 44 patients with NGB who underwent SPC with the Lowsley retractor method. The subjects were selected from 90 patients undergoing SPC by 1 surgeon from 1995 to 2010. The age, sex, indication, anesthesia type, catheter type, blood loss, fluids administered, and duration and complications were recorded. A total of 49 primary catheter placements were performed in 44 patients. A total of 23 men and 21 women were included. The etiology of NGB was spinal cord injury and multiple sclerosis in 38 subjects (86%). The mean age was 44 years (range 18-86). The cases were performed under general anesthesia, except for 8 (16%) that were successfully performed with local and monitored anesthesia. The operation time documented in 19 cases (39%) was 20.2 ± 5.5 minutes (range 11-31). The Foley catheter size ranged from 16F to 22F. The blood loss was minimal, and there were no intraoperative complications or incorrect catheter placements. One patient returned with significant hematuria 1 day after the procedure. No other minor or major complications were noted. Patients with NGB have been shown to have a greater risk of complication during percutaneous suprapubic catheter placement. SPC using the Lowsley retractor was described by Zeidman et al in 1988. Their report did not detail the patient characteristics or operative experience. To our knowledge, no other institutional experience with the technique has been reported. The present report describes the Lowsley retractor method as a quick and safe ambulatory procedure for patients with NGB. Published by Elsevier Inc.

Very late antigen-5 facilitates stromal progenitor cell differentiation into myofibroblast.

PubMed

Sen, Namita; Weingarten, Mark; Peter, Yakov

2014-11-01

Fibrotic disease is associated with abrogated stromal cell proliferation and activity. The precise identity of the cells that drive fibrosis remains obscure, in part because of a lack of information on their lineage development. To investigate the role of an early stromal progenitor cell (SPC) on the fibrotic process, we selected for, and monitored the stages of, fibroblast development from a previously reported free-floating anchorage-independent cell (AIC) progenitor population. Our findings demonstrate that organotypic pulmonary, cardiac, and renal fibroblast commitment follows a two-step process of attachment and remodeling in culture. Cell differentiation was confirmed by the inability of SPCs to revert to the free-floating state and functional mesenchymal stem/stromal cell (MSC) differentiation into osteoblast, adipocyte, chondrocyte, and fibroblastic lineages. The myofibroblastic phenotype was reflected by actin stress-fiber formation, α-smooth muscle production, and a greater than threefold increase in proliferative activity compared with that of the progenitors. SPC-derived pulmonary myofibroblasts demonstrated a more than 300-fold increase in fibronectin-1 (Fn1), collagen, type 1, α1, integrin α-5 (Itga5), and integrin β-1 (Itgb1) transcript levels. Very late antigen-5 (ITGA5/ITGB1) protein cluster formations were also prevalent on the differentiated cells. Normalized SPC-derived myofibroblast expression patterns reflected those of primary cultured lung myofibroblasts. Intratracheal implantation of pulmonary AICs into recipient mouse lungs resulted in donor cell FN1 production and evidence of epithelial derivation. SPC derivation into stromal tissue in vitro and in vivo and the observation that MSC and fibroblast lineages share a common ancestor could potentially lead to personalized antifibrotic therapies. ©AlphaMed Press.

Reversible shear-induced crystallization above equilibrium freezing temperature in a lyotropic surfactant system

PubMed Central

Rathee, Vikram; Krishnaswamy, Rema; Pal, Antara; Raghunathan, V. A.; Impéror-Clerc, Marianne; Pansu, Brigitte; Sood, A. K.

2013-01-01

We demonstrate a unique shear-induced crystallization phenomenon above the equilibrium freezing temperature in weakly swollen isotropic and lamellar mesophases with bilayers formed in a cationic-anionic mixed surfactant system. Synchrotron rheological X-ray diffraction study reveals the crystallization transition to be reversible under shear (i.e., on stopping the shear, the nonequilibrium crystalline phase melts back to the equilibrium mesophase). This is different from the shear-driven crystallization below , which is irreversible. Rheological optical observations show that the growth of the crystalline phase occurs through a preordering of the phase to an phase induced by shear flow, before the nucleation of the phase. Shear diagram of the phase constructed in the parameter space of shear rate vs. temperature exhibits and transitions above the equilibrium crystallization temperature , in addition to the irreversible shear-driven nucleation of in the phase below . In addition to revealing a unique class of nonequilibrium phase transition, the present study urges a unique approach toward understanding shear-induced phenomena in concentrated mesophases of mixed amphiphilic systems. PMID:23986497

Fluorescence Approaches to Growing Macromolecule Crystals

NASA Technical Reports Server (NTRS)

Pusey, Marc; Forsythe, Elizabeth; Achari, Aniruddha

2006-01-01

Trace fluorescent labeling, typically < 1%, can be a powerful aid in macromolecule crystallization. Precipitation concentrates a solute, and crystals are the most densely packed solid form. The more densely packed the fluorescing material, the more brightly the emission from it, and thus fluorescence intensity of a solid phase is a good indication of whether one has crystals or not. The more brightly fluorescing crystalline phase is easily distinguishable, even when embedded in an amorphous precipitate. This approach conveys several distinct advantages: one can see what the protein is doing in response to the imposed conditions, and distinguishing between amorphous and microcrystalline precipitated phases are considerably simpler. The higher fluorescence intensity of the crystalline phase led us to test if we could derive crystallization conditions from screen outcomes which had no obvious crystalline material, but simply "bright spots" in the precipitated phase. Preliminary results show that the presence of these bright spots, not observable under white light, is indeed a good indicator of potential crystallization conditions.

Ultra fast polymer network blue phase liquid crystals

NASA Astrophysics Data System (ADS)

Hussain, Zakir; Masutani, Akira; Danner, David; Pleis, Frank; Hollfelder, Nadine; Nelles, Gabriele; Kilickiran, Pinar

2011-06-01

Polymer-stabilization of blue phase liquid crystal systems within a host polymer network are reported, which enables ultrafast switching flexible displays. Our newly developed method to stabilize the blue phase in an existing polymer network (e.g., that of a polymer network liquid crystal; PNLC) has shown wide temperature stability and fast response speeds. Systems where the blue phase is stabilized in an already existing polymer network are attractive candidates for ultrafast LCDs. The technology also promises to be applied to flexible PNLC and/or polymer dispersed liquid crystal (PDLC) displays using plastic substrate such as polyethylene terephthalate (PET).

Application of the statistical process control method for prospective patient safety monitoring during the learning phase: robotic kidney transplantation with regional hypothermia (IDEAL phase 2a-b).

PubMed

Sood, Akshay; Ghani, Khurshid R; Ahlawat, Rajesh; Modi, Pranjal; Abaza, Ronney; Jeong, Wooju; Sammon, Jesse D; Diaz, Mireya; Kher, Vijay; Menon, Mani; Bhandari, Mahendra

2014-08-01

Traditional evaluation of the learning curve (LC) of an operation has been retrospective. Furthermore, LC analysis does not permit patient safety monitoring. To prospectively monitor patient safety during the learning phase of robotic kidney transplantation (RKT) and determine when it could be considered learned using the techniques of statistical process control (SPC). From January through May 2013, 41 patients with end-stage renal disease underwent RKT with regional hypothermia at one of two tertiary referral centers adopting RKT. Transplant recipients were classified into three groups based on the robotic training and kidney transplant experience of the surgeons: group 1, robot trained with limited kidney transplant experience (n=7); group 2, robot trained and kidney transplant experienced (n=20); and group 3, kidney transplant experienced with limited robot training (n=14). We employed prospective monitoring using SPC techniques, including cumulative summation (CUSUM) and Shewhart control charts, to perform LC analysis and patient safety monitoring, respectively. Outcomes assessed included post-transplant graft function and measures of surgical process (anastomotic and ischemic times). CUSUM and Shewhart control charts are time trend analytic techniques that allow comparative assessment of outcomes following a new intervention (RKT) relative to those achieved with established techniques (open kidney transplant; target value) in a prospective fashion. CUSUM analysis revealed an initial learning phase for group 3, whereas groups 1 and 2 had no to minimal learning time. The learning phase for group 3 varied depending on the parameter assessed. Shewhart control charts demonstrated no compromise in functional outcomes for groups 1 and 2. Graft function was compromised in one patient in group 3 (p<0.05) secondary to reasons unrelated to RKT. In multivariable analysis, robot training was significantly associated with improved task-completion times (p<0.01). Graft function was not adversely affected by either the lack of robotic training (p=0.22) or kidney transplant experience (p=0.72). The LC and patient safety of a new surgical technique can be assessed prospectively using CUSUM and Shewhart control chart analytic techniques. These methods allow determination of the duration of mentorship and identification of adverse events in a timely manner. A new operation can be considered learned when outcomes achieved with the new intervention are at par with outcomes following established techniques. Statistical process control techniques allowed for robust, objective, and prospective monitoring of robotic kidney transplantation and can similarly be applied to other new interventions during the introduction and adoption phase. Copyright © 2014 European Association of Urology. Published by Elsevier B.V. All rights reserved.

Analytical studies on the crystal melt interface shape in the Czochralski process for oxide single crystals

NASA Astrophysics Data System (ADS)

Jeong, Ja Hoon; Kang, In Seok

2000-09-01

Effects of the operating conditions on the crystal-melt interface shape are analytically investigated for the Czochralski process of the oxide single crystals. The ideas, which were used for the silicon single-crystal growth by Jeong et al. (J. Crystal Growth 177 (1997) 157), are extended to the oxide single-crystal growth problem by considering the internal radiation in the crystal phase and the melt phase heat transfer with the high Prandtl number. The interface shape is approximated in the simplest form as a quadratic function of radial position and an expression for the deviation from the flat interface shape is derived as a function of operating conditions. The radiative heat transfer rate between the interface and the ambient is computed by calculating the view factors for the curved interface shape with the assumption that the crystal phase is completely transparent. For the melt phase, the well-known results from the thermal boundary layer analysis are applied for the asymptotic case of high Prandtl number based on the idea that the flow field near the crystal-melt interface can be modeled as either a uniaxial or a biaxial flow. Through this work, essential information on the interface shape deformation and the effects of operating conditions are brought out for the oxide single-crystal growth.

Crucibleless crystal growth and Radioluminescence study of calcium tungstate single crystal fiber

NASA Astrophysics Data System (ADS)

Silva, M. S.; Jesus, L. M.; Barbosa, L. B.; Ardila, D. R.; Andreeta, J. P.; Silva, R. S.

2014-11-01

In this article, single phase and high optical quality scheelite calcium tungstate single crystal fibers were grown by using the crucibleless laser heated pedestal growth technique. The as-synthesized calcium tungstate powders used for shaping seed and feed rods were investigated by X-ray diffraction technique. As-grown crystals were studied by Raman spectroscopy and Radioluminescence measurements. The results indicate that in both two cases, calcined powder and single crystal fiber, only the expected scheelite CaWO4 phase was observed. It was verified large homogeneity in the crystal composition, without the presence of secondary phases. The Radioluminescence spectra of the as-grown single crystal fibers are in agreement with that present in Literature for bulk single crystals, presented a single emission band centered at 420 nm when irradiated with β-rays.

Directed self-assembly of liquid crystalline blue-phases into ideal single-crystals

NASA Astrophysics Data System (ADS)

Martínez-González, Jose A.; Li, Xiao; Sadati, Monirosadat; Zhou, Ye; Zhang, Rui; Nealey, Paul F.; de Pablo, Juan J.

2017-06-01

Chiral nematic liquid crystals are known to form blue phases--liquid states of matter that exhibit ordered cubic arrangements of topological defects. Blue-phase specimens, however, are generally polycrystalline, consisting of randomly oriented domains that limit their performance in applications. A strategy that relies on nano-patterned substrates is presented here for preparation of stable, macroscopic single-crystal blue-phase materials. Different template designs are conceived to exert control over different planes of the blue-phase lattice orientation with respect to the underlying substrate. Experiments are then used to demonstrate that it is indeed possible to create stable single-crystal blue-phase domains with the desired orientation over large regions. These results provide a potential avenue to fully exploit the electro-optical properties of blue phases, which have been hindered by the existence of grain boundaries.

Influence of Surrounding Dielectrics on the Data Retention Time of Doped Sb2Te Phase Change Material

NASA Astrophysics Data System (ADS)

Jedema, Friso; in `t Zandt, Micha; Wolters, Rob; Gravesteijn, Dirk

2011-02-01

The crystallization properties of as-deposited and laser written amorphous marks of doped Sb2Te phase change material are found to be only dependent on the top dielectric layer. A ZnS:SiO2 top dielectric layer yields a higher crystallization temperature and a larger crystal growth activation energy as compared to a SiO2 top dielectric layer, leading to superior data retention times at ambient temperatures. The observed correlation between the larger crystallization temperatures and larger crystal growth activation energies indicates that the viscosity of the phase change material in the amorphous state is dependent on the interfacial energy between the phase change material and the top dielectric layer.

Influence of crystal phases on electro-optic properties of epitaxially grown lanthanum-modified lead zirconate titanate films

NASA Astrophysics Data System (ADS)

Masuda, Shin; Seki, Atsushi; Masuda, Yoichiro

2010-02-01

We describe here how we have improved the crystal qualities and controlled the crystal phase of the lanthanum-modified lead zirconate titanate (PLZT) film without changing the composition ratio using an oxygen-pressure crystallization process. A PLZT film deposited on a SrTiO3 substrate with the largest electro-optic (EO) coefficient of 498 pm/V has been achieved by controlling the crystal phase of the film. Additionally, a fatigue-free lead zirconate titanate (PZT) capacitor with platinum electrodes has been realized by reducing the oxygen vacancies in the films.

A 106-fold enhancement in the conductivity of a discotic liquid crystal doped with only 1% (w/w) gold nanoparticles

NASA Astrophysics Data System (ADS)

Holt, Lucy A.; Bushby, Richard J.; Evans, Stephen D.; Burgess, Andrew; Seeley, Gordon

2008-03-01

The presence of 1% (w/w) of methylbenzene thiol coated gold nanoparticles increases the conductivity of the discotic liquid crystal 2,3,6,7,10,11-hexakis(hexyloxy)triphenylene (HAT6) by about two orders of magnitude in all three phases (crystal, columnar liquid crystal, and isotropic liquid). However, when a field (above a certain critical value) is applied to the isotropic phase, the conductivity rapidly increases by another three or four orders of magnitude after which the higher conductivity is maintained regardless of phase, field, or temperature. This increase in conductivity is attributed to the formation of chains of gold nanoparticles. A similar phenomenon is observed for 1% (w/w) gold nanoparticles in the isotropic phase of hexadecane. However, the liquid crystal/nanoparticle mixture preserves its high conductivity when it is cooled into the crystalline phase whereas that of the hexadecane/nanoparticle mixture is lost. In hexadecane, crystal grain boundaries are expected to form in a random fashion and this disrupts the conductive pathways. However, if HAT6 crystallizes via the homeotropically aligned columnar phase, the grain boundaries form predominantly surface to surface (electrode to electrode) so that the conductive nanoparticle chains are trapped in a stabilizing solid matrix.

On crystal versus fiber formation in dipeptide hydrogelator systems.

PubMed

Houton, Kelly A; Morris, Kyle L; Chen, Lin; Schmidtmann, Marc; Jones, James T A; Serpell, Louise C; Lloyd, Gareth O; Adams, Dave J

2012-06-26

Naphthalene dipeptides have been shown to be useful low-molecular-weight gelators. Here we have used a library to explore the relationship between the dipeptide sequence and the hydrogelation efficiency. A number of the naphthalene dipeptides are crystallizable from water, enabling us to investigate the comparison between the gel/fiber phase and the crystal phase. We succeeded in crystallizing one example directly from the gel phase. Using X-ray crystallography, molecular modeling, and X-ray fiber diffraction, we show that the molecular packing of this crystal structure differs from the structure of the gel/fiber phase. Although the crystal structures may provide important insights into stabilizing interactions, our analysis indicates a rearrangement of structural packing within the fibers. These observations are consistent with the fibrillar interactions and interatomic separations promoting 1D assembly whereas in the crystals the peptides are aligned along multiple axes, allowing 3D growth. This observation has an impact on the use of crystal structures to determine supramolecular synthons for gelators.

Discovery of a metastable Al20Sm4 phase

NASA Astrophysics Data System (ADS)

Ye, Z.; Zhang, F.; Sun, Y.; Mendelev, M. I.; Ott, R. T.; Park, E.; Besser, M. F.; Kramer, M. J.; Ding, Z.; Wang, C.-Z.; Ho, K.-M.

2015-03-01

We present an efficient genetic algorithm, integrated with experimental diffraction data, to solve a nanoscale metastable Al20Sm4 phase that evolves during crystallization of an amorphous magnetron sputtered Al90Sm10 alloy. The excellent match between calculated and experimental X-ray diffraction patterns confirms an accurate description of this metastable phase. Molecular dynamic simulations of crystal growth from the liquid phase predict the formation of disordered defects in the devitrified crystal.

Phase transitions of antibiotic clarithromycin forms I, IV and new form VII crystals.

PubMed

Ito, Masataka; Shiba, Rika; Watanabe, Miteki; Iwao, Yasunori; Itai, Shigeru; Noguchi, Shuji

2018-06-01

Metastable crystal form I of the antibiotic clarithromycin has a pharmaceutically valuable characteristic that its crystalline phase transition can be applied for its sustained release from tablets. The phase transition of form I was investigated in detail by single crystal and powder X-ray analyses, dynamic vapor sorption analysis and thermal analysis. The single crystal structure of form I revealed that form I was not an anhydrate crystal but contained a partially occupied water molecule in the channel-like void space. Dynamic vapor sorption (DVS) analysis demonstrated that form I crystals reversibly sorbed water molecules in two steps when the relative humidity (RH) increased and finally transited to hydrate form IV at 95% RH. DVS analysis also showed that when the RH decreased form IV crystals lost water molecules at 40% RH and transited to the newly identified anhydrate crystal form VII. Form VII reversibly transited to form IV at lower RH than form I, suggesting that form I is more suitable for manufacturing a sustained-release tablet of CAM utilizing the crystalline phase transition. Copyright © 2018 Elsevier B.V. All rights reserved.

Zak phase induced multiband waveguide by two-dimensional photonic crystals.

PubMed

Yang, Yuting; Xu, Tao; Xu, Yun Fei; Hang, Zhi Hong

2017-08-15

Interface states in photonic crystals provide efficient approaches to control the flow of light. Photonic Zak phase determines the bulk band properties of photonic crystals, and, by assembling two photonic crystals with different bulk band properties together, deterministic interface states can be realized. By translating each unit cell of a photonic crystal by half the lattice constant, another photonic crystal with identical common gaps but a different Zak phase at each photonic band can be created. By assembling these two photonic crystals together, multiband waveguide can thus be easily created and then experimentally characterized. Our experimental results have good agreement with numerical simulations, and the propagation properties of these measured interface states indicate that this new type of interface state will be a good candidate for future applications of optical communications.

RH-temperature phase diagrams of hydrate forming deliquescent crystalline ingredients.

PubMed

Allan, Matthew; Mauer, Lisa J

2017-12-01

Several common deliquescent crystalline food ingredients (including glucose and citric acid) are capable of forming crystal hydrate structures. The propensity of such crystals to hydrate/dehydrate or deliquesce is dependent on the environmental temperature and relative humidity (RH). As an anhydrous crystal converts to a crystal hydrate, water molecules internalize into the crystal structure resulting in different physical properties. Deliquescence is a solid-to-solution phase transformation. RH-temperature phase diagrams of the food ingredients alpha-d-glucose and citric acid, along with sodium sulfate, were produced using established and newly developed methods. Each phase diagram included hydrate and anhydrate deliquescence boundaries, the anhydrate-hydrate phase boundary, and the peritectic temperature (above which the hydrate was no longer stable). This is the first report of RH-temperature phase diagrams of glucose and citric acid, information which is beneficial for selecting storage and processing conditions to promote or avoid hydrate formation or loss and/or deliquescence. Copyright © 2017 Elsevier Ltd. All rights reserved.

Crystal phase-based epitaxial growth of hybrid noble metal nanostructures on 4H/fcc Au nanowires

NASA Astrophysics Data System (ADS)

Lu, Qipeng; Wang, An-Liang; Gong, Yue; Hao, Wei; Cheng, Hongfei; Chen, Junze; Li, Bing; Yang, Nailiang; Niu, Wenxin; Wang, Jie; Yu, Yifu; Zhang, Xiao; Chen, Ye; Fan, Zhanxi; Wu, Xue-Jun; Chen, Jinping; Luo, Jun; Li, Shuzhou; Gu, Lin; Zhang, Hua

2018-03-01

Crystal-phase engineering offers opportunities for the rational design and synthesis of noble metal nanomaterials with unusual crystal phases that normally do not exist in bulk materials. However, it remains a challenge to use these materials as seeds to construct heterometallic nanostructures with desired crystal phases and morphologies for promising applications such as catalysis. Here, we report a strategy for the synthesis of binary and ternary hybrid noble metal nanostructures. Our synthesized crystal-phase heterostructured 4H/fcc Au nanowires enable the epitaxial growth of Ru nanorods on the 4H phase and fcc-twin boundary in Au nanowires, resulting in hybrid Au-Ru nanowires. Moreover, the method can be extended to the epitaxial growth of Rh, Ru-Rh and Ru-Pt nanorods on the 4H/fcc Au nanowires to form unique hybrid nanowires. Importantly, the Au-Ru hybrid nanowires with tunable compositions exhibit excellent electrocatalytic performance towards the hydrogen evolution reaction in alkaline media.

A polarization-independent liquid crystal phase modulation using polymer-network liquid crystal with orthogonal alignment layers

NASA Astrophysics Data System (ADS)

Chen, Ming-Syuan; Lin, Wei-Chih; Tsou, Yu-Shih; Lin, Yi-Hsin

2012-10-01

A polarization-independent liquid crystal (LC) phase modulation using polymer-network liquid crystals with orthogonal alignments layers (T-PNLC) is demonstrated. T-PNLC consists of three layers. LC directors in the two layers near glass substrates are orthogonal to each other. In the middle layer, LC directors are perpendicular to the glass substrate. The advantages of such T-PNLC include polarizer-free, larger phase shift (~0.4π rad) than the residual phase type (<0.05π rad), and low operating voltage (< 30Vrms). It does not require bias voltage for avoiding scattering because the refractive index of liquid crystals matches that of polymers. The phase shift of T-PNLC is affected by the cell gap and the curing voltages. The potential applications are laser beam steering, spatial light modulators and electrically tunable micro-lens arrays.

Application of machine learning and expert systems to Statistical Process Control (SPC) chart interpretation

NASA Technical Reports Server (NTRS)

Shewhart, Mark

1991-01-01

Statistical Process Control (SPC) charts are one of several tools used in quality control. Other tools include flow charts, histograms, cause and effect diagrams, check sheets, Pareto diagrams, graphs, and scatter diagrams. A control chart is simply a graph which indicates process variation over time. The purpose of drawing a control chart is to detect any changes in the process signalled by abnormal points or patterns on the graph. The Artificial Intelligence Support Center (AISC) of the Acquisition Logistics Division has developed a hybrid machine learning expert system prototype which automates the process of constructing and interpreting control charts.

Single Photon Counting Performance and Noise Analysis of CMOS SPAD-Based Image Sensors.

PubMed

Dutton, Neale A W; Gyongy, Istvan; Parmesan, Luca; Henderson, Robert K

2016-07-20

SPAD-based solid state CMOS image sensors utilising analogue integrators have attained deep sub-electron read noise (DSERN) permitting single photon counting (SPC) imaging. A new method is proposed to determine the read noise in DSERN image sensors by evaluating the peak separation and width (PSW) of single photon peaks in a photon counting histogram (PCH). The technique is used to identify and analyse cumulative noise in analogue integrating SPC SPAD-based pixels. The DSERN of our SPAD image sensor is exploited to confirm recent multi-photon threshold quanta image sensor (QIS) theory. Finally, various single and multiple photon spatio-temporal oversampling techniques are reviewed.

Solubility of methane in water: the significance of the methane-water interaction potential.

PubMed

Konrad, Oliver; Lankau, Timm

2005-12-15

The influence of the methane-water interaction potential on the value of the Henry constant obtained from molecular dynamics simulations was investigated. The SPC, SPC/E, MSPC/E, and TIP3P potentials were used to describe water and the OPLS-UA and TraPPE potentials for methane. Nonbonding interactions between unlike atoms were calculated both with one of four mixing rules and with our new methane-water interaction potential. The Henry constants obtained from simulations using any of the mixing rules differed significantly from the experimental ones. Good agreement between simulation and experiment was achieved with the new potential over the whole temperature range.

PISCES: An Integral Field Spectrograph Technology Demonstration for the WFIRST Coronagraph

NASA Technical Reports Server (NTRS)

McElwain, Michael W.; Mandell, Avi M.; Gong, Qian; Llop-Sayson, Jorge; Brandt, Timothy; Chambers, Victor J.; Grammer, Bryan; Greeley, Bradford; Hilton, George; Perrin, Marshall D.;

PISCES: an integral field spectrograph technology demonstration for the WFIRST coronagraph

NASA Astrophysics Data System (ADS)

McElwain, Michael W.; Mandell, Avi M.; Gong, Qian; Llop-Sayson, Jorge; Brandt, Timothy; Chambers, Victor J.; Grammer, Bryan; Greeley, Bradford; Hilton, George; Perrin, Marshall D.; Stapelfeldt, Karl R.; Demers, Richard; Tang, Hong; Cady, Eric

2016-07-01

We present the design, integration, and test of the Prototype Imaging Spectrograph for Coronagraphic Exoplanet Studies (PISCES) integral field spectrograph (IFS). The PISCES design meets the science requirements for the Wide-Field InfraRed Survey Telescope (WFIRST) Coronagraph Instrument (CGI). PISCES was integrated and tested in the integral field spectroscopy laboratory at NASA Goddard. In June 2016, PISCES was delivered to the Jet Propulsion Laboratory (JPL) where it was integrated with the Shaped Pupil Coronagraph (SPC) High Contrast Imaging Testbed (HCIT). The SPC/PISCES configuration will demonstrate high contrast integral field spectroscopy as part of the WFIRST CGI technology development program.

Specific targeting and toxicity of sulphonated aluminium phthalocyanine photosensitised liposomes directed to cells by monoclonal antibody in vitro.

PubMed Central

Morgan, J.; Gray, A. G.; Huehns, E. R.

1989-01-01

A partially purified fraction of the water soluble photosensitive dye sulphonated aluminium phthalocyanine (AlSPc) was encapsulated in liposomes which were then linked to a targeting monoclonal antibody 791T/36 using a heterobifunctional linking agent. The photocytotoxic effects of the liposomes were determined on two cell lines bearing an antigen with which the targeting antibody binds: 791T, an osteosarcoma and C170, a colorectal carcinoma; and a control cell line not bearing the antigen; DW-BCL, an Epstein-Barr virus immortalised B-cell line. Antibody dependent cytotoxicity was observed in 791T and C170 cells and was proportional to the number of antigens on the cells, the AlSPc concentration and the time of exposure to activating red light. No significant toxicity was seen using untargeted liposomes, control cells or free AlSPc fraction under similar conditions. Targeted cells and controls kept in the dark also showed no significant toxicity. A possible mechanism of action is postulated and simple adaptations which demonstrate the versatility of the model are discussed. Some suggestions as to the clinical situations to which this system might be applied in the form of photodynamic therapy (PDT) are made. PMID:2930700

Modelling catheter-vein biomechanical interactions during an intravenous procedure.

PubMed

Weiss, Dar; Gefen, Amit; Einav, Shmuel

2016-02-01

A reliable intravenous (IV) access into the upper extremity veins requires the insertion of a temporary short peripheral catheter (SPC). This so common procedure is, however, associated with a risk of developing short peripheral catheter thrombophlebitis (SPCT) which causes distress and potentially prolongs patient hospitalization. We have developed and studied a biomechanical SPC-vein computational model during an IV procedure, and explored the biomechanical effects of repeated IV episodes on onset and reoccurrences of SPCT. The model was used to determine the effects of different insertion techniques as well as inter-patient biological variability on the catheter-vein wall contact pressures and wall deformations. We found that the maximal pressure exerted upon the vein wall was inhomogeneously distributed, and that the bending region was exposed to significantly greater pressures and deformations. The maximal exerted contact pressure on the inner vein's wall was 2938 Pa. The maximal extent of the SPC penetration into the vein wall reached 3.6 μm, which corresponds to approximately 100% of the average height of the inner layer, suggesting local squashing of endothelial cells at the contact site. The modelling describes a potential biomechanical damage pathway that can explain the reoccurrence of SPCT.

In vitro generation of type-II pneumocytes can be initiated in human CD34(+) stem cells.

PubMed

Srikanth, Lokanathan; Venkatesh, Katari; Sunitha, Manne Mudhu; Kumar, Pasupuleti Santhosh; Chandrasekhar, Chodimella; Vengamma, Bhuma; Sarma, Potukuchi Venkata Gurunadha Krishna

2016-02-01

Human CD34(+) stem cells differentiated into type-II pneumocytes in Dulbecco's modified Eagle medium (DMEM) having hydrocortisone, insulin, fibroblast growth factor (FGF), epidermal growth factor (EGF) and bovine serum albumin (BSA), expressing surfactant proteins-B (SP-B) and C (SP-C), alkaline phosphatase (ALP) and lysozyme. FACS-enumerated pure CD34(+) cells, isolated from human peripheral blood, were cultured in DMEM and showed positive reaction with anti-human CD34 monoclonal antibodies in immunocytochemistry. These cells were cultured in DMEM having hydrocortisone, insulin, FGF, EGF and BSA (HIFEB-D) medium having an air-liquid interface. They differentiated into type-II pneumocytes with expression of SP-B and SP-C genes and disappearance of CD34 expression as assessed using real-time PCR. In reverse transcription-PCR amplicons showed 208 and 907 bp confirming SP-B and SP-C expressions. These cells expressed ALP with an activity of 1.05 ± 0.09 mM ml(-1) min(-1) and lysozyme that killed E. coli. The successful differentiation of human CD34(+) stem cells into type-II pneumocytes, and transplantation of such cells obtained from the patient's stem cell could be the futuristic approach to regenerate diseased lung alveoli.

Automated process control for plasma etching

NASA Astrophysics Data System (ADS)

McGeown, Margaret; Arshak, Khalil I.; Murphy, Eamonn

1992-06-01

This paper discusses the development and implementation of a rule-based system which assists in providing automated process control for plasma etching. The heart of the system is to establish a correspondence between a particular data pattern -- sensor or data signals -- and one or more modes of failure, i.e., a data-driven monitoring approach. The objective of this rule based system, PLETCHSY, is to create a program combining statistical process control (SPC) and fault diagnosis to help control a manufacturing process which varies over time. This can be achieved by building a process control system (PCS) with the following characteristics. A facility to monitor the performance of the process by obtaining and analyzing the data relating to the appropriate process variables. Process sensor/status signals are input into an SPC module. If trends are present, the SPC module outputs the last seven control points, a pattern which is represented by either regression or scoring. The pattern is passed to the rule-based module. When the rule-based system recognizes a pattern, it starts the diagnostic process using the pattern. If the process is considered to be going out of control, advice is provided about actions which should be taken to bring the process back into control.

Static dielectric constant of water within a bilayer using recent water models: a molecular dynamics study

NASA Astrophysics Data System (ADS)

Meneses-Juárez, Efrain; Rivas-Silva, Juan Francisco; González-Melchor, Minerva

2018-05-01

The water confined within a surfactant bilayer is studied using different water models via molecular dynamics simulations. We considered four representative rigid models of water: the SPC/E and the TIP4P/2005, which are commonly used in numerical calculations and the more recent TIP4Q and SPC/ε models, developed to reproduce the dielectric behaviour of pure water. The static dielectric constant of the confined water was analyzed as a function of the temperature for the four models. In all cases it decreases as the temperature increases. Additionally, the static dielectric constant of the bilayer-water system was estimated through its expression in terms of the fluctuations in the total dipole moment, usually applied for isotropic systems. The estimated dielectric was compared with the available experimental data. We found that the TIP4Q and the SPC/ε produce closer values to the experimental data than the other models, particularly at room temperature. It was found that the probability of finding the sodium ion close to the head of the surfactant decreases as the temperature increases, thus the head of the surfactant is more exposed to the interaction with water when the temperature is higher.

Systematic review of the use of Statistical Process Control methods to measure the success of pressure ulcer prevention.

PubMed

Clark, Michael; Young, Trudie; Fallon, Maureen

2018-06-01

Successful prevention of pressure ulcers is the end product of a complex series of care processes including, but not limited to, the assessment of vulnerability to pressure damage; skin assessment and care; nutritional support; repositioning; and the use of beds, mattresses, and cushions to manage mechanical loads on the skin and soft tissues. The purpose of this review was to examine where and how Statistical Process Control (SPC) measures have been used to assess the success of quality improvement initiatives intended to improve pressure ulcer prevention. A search of 7 electronic bibliographic databases was performed on May 17th, 2017, for studies that met the inclusion criteria. SPC methods have been reported in 9 publications since 2010 to interpret changes in the incidence of pressure ulcers over time. While these methods offer rapid interpretation of changes in incidence than is gained from a comparison of 2 arbitrarily selected time points pre- and post-implementation of change, more work is required to ensure that the clinical and scientific communities adopt the most appropriate SPC methods. © 2018 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

A Longitudinal Study of Commonly Used Admissions Measures and Disenrollment from Medical School and Graduate Medical Education Probation or Termination from Training.

PubMed

Dong, Ting; Gilliland, William R; Cruess, David; Hutchinson, Jeffrey; Morres, Lisa; Curtis, Jerri; Hewitt-Clarke, Gail-Selina; Durning, Steven J

2018-04-27

This is an empirical study to better understand commonly used medical school admission measures and disenrollment decisions during undergraduate medical education as well as graduate medical education (GME) probation or termination decisions. Based on the data of USUHS medical students matriculating between 1998 and 2011 (N = 2,460), we compared medical school graduates and those disenrolled from medical school on MCAT scores, undergraduate BCPM (Biology, Chemistry, Physics, Math) GPA, and undergraduate overall GPA. We also reported more specific reasons for disenrollment decisions. Next, we compared the students who were referred to the student promotion committee (SPC) with other students on these measures. Moving onto GME, we compared trainees who were put on probation or terminated from training with those who were not on MCAT and undergraduate GPA measures. In addition, we examined the association between being referred to the SPC and GME probation or termination. There were 2,347 graduates and 113 disenrolled students from medical school (4.8%). For the disenrolled students, 43 (38.7%) students were disenrolled for exclusively (or primarily) non-academic reasons, and 68 (61.3%) were disenrolled for exclusively (or primarily) academic reasons. The t-tests showed statistically significant differences on the MCAT score of the first attempt (t(2,449) = 7.22, P < 0.01, Cohen's d = 0.70), average MCAT score (t(2,449) = 4.22, P < 0.01, Cohen's d = 0.41), and highest MCAT score (t(2,449) = 3.51, P < 0.01, Cohen's d = 0.34). Logistic regression model selection also revealed that the best predictor for disenrollment was the first MCAT score (exp(b) = 0.83, 95% CI = (0.78, 0.88)). No significant differences on these measures were found from the group comparisons on SPC and GME probation or termination. There was no significant association between SPC appearance and GME probation or termination. Academic difficulties, especially in the basic sciences, appear to be the most common factor for disenrollment from medical school. These students also had lower MCAT scores, particularly on the first attempt. The MCAT performance indicators and undergraduate GPA were consistently lower, but not statistically significant, for those who appeared before SPC or were put on probation or terminated from training during GME.

The clinical phenotype of hereditary versus sporadic prostate cancer: HPC definition revisited.

PubMed

Cremers, Ruben G; Aben, Katja K; van Oort, Inge M; Sedelaar, J P Michiel; Vasen, Hans F; Vermeulen, Sita H; Kiemeney, Lambertus A

2016-07-01

The definition of hereditary prostate cancer (HPC) is based on family history and age at onset. Intuitively, HPC is a serious subtype of prostate cancer but there are only limited data on the clinical phenotype of HPC. Here, we aimed to compare the prognosis of HPC to the sporadic form of prostate cancer (SPC). HPC patients were identified through a national registry of HPC families in the Netherlands, selecting patients diagnosed from the year 2000 onward (n = 324). SPC patients were identified from the Netherlands Cancer Registry (NCR) between 2003 and 2006 for a population-based study into the genetic susceptibility of PC (n = 1,664). Detailed clinical data were collected by NCR-registrars, using a standardized registration form. Follow-up extended up to the end of 2013. Differences between the groups were evaluated by cross-tabulations and tested for statistical significance while accounting for familial dependency of observations by GEE. Differences in progression-free and overall survival were evaluated using χ(2) testing with GEE in a proportional-hazards model. HPC patients were on average 3 years younger at diagnosis, had lower PSA values, lower Gleason scores, and more often locally confined disease. Of the HPC patients, 35% had high-risk disease (NICE-criteria) versus 51% of the SPC patients. HPC patients were less often treated with active surveillance. Kaplan-Meier 5-year progression-free survival after radical prostatectomy was comparable for HPC (78%) and SPC (74%; P = 0.30). The 5-year overall survival was 85% (95%CI 81-89%) for HPC versus 80% (95%CI 78-82%) for SPC (P = 0.03). HPC has a favorable clinical phenotype but patients more often underwent radical treatment. The major limitation of HPC is the absence of a genetics-based definition of HPC, which may lead to over-diagnosis of PC in men with a family history of prostate cancer. The HPC definition should, therefore, be re-evaluated, aiming at a reduction of over-diagnosis and overtreatment among men with multiple relatives diagnosed with PC. Prostate 76:897-904, 2016. © 2016 The Authors. The Prostate published by Wiley Periodicals, Inc. © 2016 The Authors. The Prostate published by Wiley Periodicals, Inc.

Phase diagrams and crystal growth

NASA Astrophysics Data System (ADS)

Venkrbec, Jan

1980-04-01

Phase diagrams are briefly treated as generalized property-composition relationships, with respect to crystal technology optimization. The treatment is based on mutual interaction of three systems related to semiconductors: (a) the semiconducting material systems, (b0 the data bank, (c) the system of crystallization methods. A model is proposed enabling optimatization on the path from application requirements to the desired material. Further, several examples of the selection as to the composition of LED and laser diode material are given. Some of molten-solution-zone methods are being successfully introduced for this purpose. Common features of these methods, the application of phase diagrams, and their pecularities compared with other crystallization methods are illustrated by schematic diagrams and by examples. LPE methods, particularly the steady-state LPE methods such as Woodall's ISM and Nishizawa's TDM-CVP, and the CAM-S (Crystallization Method Providing Composition Autocontrol in Situ) have been chosen as examples. Another approach of exploiting phase diagrams for optimal material selection and for determination of growth condition before experimentation through a simple calculation is presented on InP-GaP solid solutions. Ternary phase diagrams are visualized in space through calculation and constructions based on the corresponding thermodynamic models and anaglyphs. These make it easy to observe and qualitatively analyze the crystallization of every composition. Phase diagrams can be also used as a powerful tool for the deduction of new crystallization methods. Eutectic crystallization is an example of such an approach where a modified molten-solution-zone method can give a sandwich structure with an abrupt concentration change. The concentration of a component can range from 0 to 100% in the different solid phases.

A polarization-independent liquid crystal phase modulation using polymer-network liquid crystals in a 90° twisted cell

NASA Astrophysics Data System (ADS)

Lin, Yi-Hsin; Chen, Ming-Syuan; Lin, Wei-Chih; Tsou, Yu-Shih

2012-07-01

A polarization-independent liquid crystal phase modulation using polymer-network liquid crystals in a 90° twisted cell (T-PNLC) is demonstrated. T-PNLC consists of three layers. Liquid crystal (LC) directors in the two layers near glass substrates are orthogonal to each other and those two layers modulate two eigen-polarizations of an incident light. As a result, two eigen-polarizations of an incident light experience the same phase shift. In the middle layer, LC directors are perpendicular to the glass substrate and contribute no phase shift. The phase shift of T-PNLC is electrically tunable and polarization-independent. T-PNLC does not require any bias voltage for operation. The phase shift is 0.28 π rad for the voltage of 30 Vrms. By measuring and analyzing the optical phase shift of T-PNLC at the oblique incidence of transverse magnetic wave, the pretilt angle of LC directors and the effective thickness of three layers are obtained and discussed. The potential applications are spatial light modulators, laser beam steering, and micro-lens arrays.

Homeotropic alignment of multiple bent-core liquid crystal phases using a polydimethylsiloxane alignment layer

NASA Astrophysics Data System (ADS)

Carlson, Eric D.; Foley, Lee M.; Guzman, Edward; Korblova, Eva D.; Visvanathan, Rayshan; Ryu, SeongHo; Gim, Min-Jun; Tuchband, Michael R.; Yoon, Dong Ki; Clark, Noel A.; Walba, David M.

2017-08-01

The control of the molecular orientation of liquid crystals (LCs) is important in both understanding phase properties and the continuing development of new LC technologies including displays, organic transistors, and electro-optic devices. Many techniques have been developed for successfully inducing alignment of calamitic LCs, though these techniques typically do not translate to the alignment of bent-core liquid crystals (BCLCs). Some techniques have been utilized to align various phases of BCLCs, but these techniques are often unsuccessful for general alignment of multiple materials and/or multiple phases. Here, we demonstrate that glass cells treated with polydimethylsiloxane (PDMS) thin films induce high quality homeotropic alignment of multiple mesophases of four BCLCs. On cooling to the lowest temperature phase the homeotropic alignment is lost, and spherulitic growth is seen in crystal and crystal-like phases including the dark conglomerate (DC) and helical nanofilament (HNF) phases. Evidence of homeotropic alignment is observed using polarized optical microscopy. We speculate that the methyl groups on the surface of the PDMS films strongly interact with the aliphatic tails of each mesogens, resulting in homeotropic alignment.

Kinetics and pathways for crystallization of amorphous mullite and YAG

NASA Astrophysics Data System (ADS)

Johnson, Bradley Richard

The crystallization behavior of quenched mullite (3Al2O 3•2SiO2) and YAG (Y3Al5O 12) composition glasses (made using containerless methods) were characterized with the ultimate goal of producing single crystal, structural, ceramic oxide fibers from these materials. The kinetics for crystallization were determined from thermal analysis experiments. From the results, time-temperature-transformation (TTT) curves were calculated. The crystallization pathways were determined by examining the crystal structure, microstructure, and chemical composition of heat treated specimens using x-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). A machine was also designed and built to facilitate controlled crystallization of amorphous fibers. Quenched, Y3Al5O12 composition beads crystallized at temperatures as low as 840°C. The as-received specimens contained a few, small YAG crystals, in addition to a mixture of different amorphous phases. The coexistence of two different amorphous phases of the same composition, but having different densities is termed polyamorphism, and this has been reported to occur in Y3Al5O12 composition quenched melts. Although various crystallization pathways have been reported for chemically synthesized YAG precursors, these specimens crystallized directly into YAG, which was the only phase formed. Quenched, 3Al2O3•2SiO2 composition mullite beads and fibers crystallized at temperatures as low as 920°C. Due to phase separation in the quenched melts, multiple phases with slightly different compositions and different crystallization activation energies crystallized. These phases were not equilibrium, 3:2 mullite, but metastable, alumina-rich, pseudotetragonal mullite. The residual, amorphous, silica-rich phase existed as numerous, 7--10 nm sized inclusions embedded within pseudotetragonal mullite. A large amount of internal strain was detected in pseudotetragonal mullite, and the source of this strain was suggested to be the embedded, silica-rich inclusions. Pseudotetragonal mullite gradually converted to equilibrium, orthorhombic, 3:2 mullite between 1000--1400°C. This was characterized by assimilation of the embedded, silica-rich inclusions and the elimination of internal strain. Additionally, recrystallization of numerous, small, strain- and inclusion-free, 3:2 mullite grains was observed to occur as the process proceeded to completion.

Phase equilibria in the lysozyme-ammonium sulfate-water system.

PubMed

Moretti, J J; Sandler, S I; Lenhoff, A M

2000-12-05

Ternary phase diagrams were measured for lysozyme in ammonium sulfate solutions at pH values of 4 and 8. Lysozyme, ammonium sulfate, and water mass fractions were assayed independently by UV spectroscopy, barium chloride titration, and lyophilization respectively, with mass balances satisfied to within 1%. Protein crystals, flocs, and gels were obtained in different regions of the phase diagrams, and in some cases growth of crystals from the gel phase or from the supernatant after floc removal was observed. These observations, as well as a discontinuity in protein solubility between amorphous floc precipitate and crystal phases, indicate that the crystal phase is the true equilibrium state. The ammonium sulfate was generally found to partition unequally between the supernatant and the dense phase, in disagreement with an assumption often made in protein phase equilibrium studies. The results demonstrate the potential richness of protein phase diagrams as well as the uncertainties resulting from slow equilibration. Copyright 2000 John Wiley & Sons, Inc.

Computerized Liquid Crystal Phase Identification by Neural Networks Analysis of Polarizing Microscopy Textures

NASA Astrophysics Data System (ADS)

Karaszi, Zoltan; Konya, Andrew; Dragan, Feodor; Jakli, Antal; CPIP/LCI; CS Dept. of Kent State University Collaboration

Polarizing optical microscopy (POM) is traditionally the best-established method of studying liquid crystals, and using POM started already with Otto Lehman in 1890. An expert, who is familiar with the science of optics of anisotropic materials and typical textures of liquid crystals, can identify phases with relatively large confidence. However, for unambiguous identification usually other expensive and time-consuming experiments are needed. Replacement of the subjective and qualitative human eye-based liquid crystal texture analysis with quantitative computerized image analysis technique started only recently and were used to enhance the detection of smooth phase transitions, determine order parameter and birefringence of specific liquid crystal phases. We investigate if the computer can recognize and name the phase where the texture was taken. To judge the potential of reliable image recognition based on this procedure, we used 871 images of liquid crystal textures belonging to five main categories: Nematic, Smectic A, Smectic C, Cholesteric and Crystal, and used a Neural Network Clustering Technique included in the data mining software package in Java ``WEKA''. A neural network trained on a set of 827 LC textures classified the remaining 44 textures with 80% accuracy.

Phase diagram of a symmetric electron–hole bilayer system: a variational Monte Carlo study

NASA Astrophysics Data System (ADS)

Sharma, Rajesh O.; Saini, L. K.; Prasad Bahuguna, Bhagwati

2018-05-01

We study the phase diagram of a symmetric electron–hole bilayer system at absolute zero temperature and in zero magnetic field within the quantum Monte Carlo approach. In particular, we conduct variational Monte Carlo simulations for various phases, i.e. the paramagnetic fluid phase, the ferromagnetic fluid phase, the anti-ferromagnetic Wigner crystal phase, the ferromagnetic Wigner crystal phase and the excitonic phase, to estimate the ground-state energy at different values of in-layer density and inter-layer spacing. Slater–Jastrow style trial wave functions, with single-particle orbitals appropriate for different phases, are used to construct the phase diagram in the (r s , d) plane by finding the relative stability of trial wave functions. At very small layer separations, we find that the fluid phases are stable, with the paramagnetic fluid phase being particularly stable at and the ferromagnetic fluid phase being particularly stable at . As the layer spacing increases, we first find that there is a phase transition from the ferromagnetic fluid phase to the ferromagnetic Wigner crystal phase when d reaches 0.4 a.u. at r s   =  20, and before there is a return to the ferromagnetic fluid phase when d approaches 1 a.u. However, for r s   <  20 and a.u., the excitonic phase is found to be stable. We do not find that the anti-ferromagnetic Wigner crystal is stable over the considered range of r s and d. We also find that as r s increases, the critical layer separations for Wigner crystallization increase.

Structure, dielectric and electric properties of diisobutylammonium hydrogen sulfate crystal

NASA Astrophysics Data System (ADS)

Bednarchuk, Tamara J.; Kinzhybalo, Vasyl; Markiewicz, Ewa; Hilczer, Bożena; Pietraszko, Adam

2018-02-01

Diisobutylammonium hydrogen sulfate, a new organic-inorganic hybrid compound, was successfully synthesized and three structural phases in 298-433 K temperature range were revealed by differential scanning calorimetry and X-ray powder diffraction studies. Single crystal X-ray diffraction data were used to describe the crystal structures in each particular case. In phase III (below 336/319 K on heating/cooling) the crystal arrangement appears to be within the triclinic symmetry with P-1 space group. During heating in the 336-339 K region (and 319-337 K on cooling) the crystal exists in the phase II, characterized by monoclinic symmetry with P21/c space group. Consequently, above 339 K (during heating, and 337 K during cooling temperature sequences), i.e. in phase I the crystal exhibits orthorhombic symmetry (Cmce space group). Ferroelastic domain structure was observed in phase III. These phase boundaries (III→II and II→I) were accompanied by the presence of small anomalies, apparent in the dielectric permittivity and electric conductivity experimental data. Fast proton transport with activation energy of 0.23 eV was observed in the high temperature phase I and related to phonon assisted proton diffusion conditioned by disorder of diisobutylammonium (diba) cations, as well as by high thermal displacements of oxygen and sulfur atoms of hydrogen sulfate anion (hs).

Prediction of a New Phase of Cu x S near Stoichiometric Composition

DOE PAGES

Khatri, Prashant; Huda, Muhammad N.

2015-01-01

Cumore » 2 S is known to be a promising solar absorber material due to its suitable band gap and the abundance of its constituent elements. 2 S is known to have complex phase structures depending on the concentration of vacancies. Its instability of phases is due to favorable formation of vacancies and the mobility of atoms within the crystal. Understanding its phase structures is of crucial important for its application as solar absorber material. In this paper, we have predicted a new crystal phase of copper sulfide ( x S) around chemical composition of x = 1.98 by utilizing crystal database search and density functional theory. We have shown that this new crystal phase of x S is more favorable than low chalcocite structure even at stoichiometric composition of x = 2 . However, vacancy formation probability was found to be higher in this new phase than the low chalcocite structure.« less

Thermodynamics around the first-order ferromagnetic phase transition of Fe2P single crystals

NASA Astrophysics Data System (ADS)

Hudl, M.; Campanini, D.; Caron, L.; Höglin, V.; Sahlberg, M.; Nordblad, P.; Rydh, A.

2014-10-01

The specific heat and thermodynamics of Fe2P single crystals around the first-order paramagnetic to ferromagnetic (FM) phase transition at TC≃217 K are empirically investigated. The magnitude and direction of the magnetic field relative to the crystal axes govern the derived H -T phase diagram. Strikingly different phase contours are obtained for fields applied parallel and perpendicular to the c axis of the crystal. In parallel fields, the FM state is stabilized, while in perpendicular fields the phase transition is split into two sections, with an intermediate FM phase where there is no spontaneous magnetization along the c axis. The zero-field transition displays a textbook example of a first-order transition with different phase stability limits on heating and cooling. The results have special significance since Fe2P is the parent material to a family of compounds with outstanding magnetocaloric properties.

Monoolein Lipid Phases as Incorporation and Enrichment Materials for Membrane Protein Crystallization

PubMed Central

Wallace, Ellen; Dranow, David; Laible, Philip D.; Christensen, Jeff; Nollert, Peter

2011-01-01

The crystallization of membrane proteins in amphiphile-rich materials such as lipidic cubic phases is an established methodology in many structural biology laboratories. The standard procedure employed with this methodology requires the generation of a highly viscous lipidic material by mixing lipid, for instance monoolein, with a solution of the detergent solubilized membrane protein. This preparation is often carried out with specialized mixing tools that allow handling of the highly viscous materials while minimizing dead volume to save precious membrane protein sample. The processes that occur during the initial mixing of the lipid with the membrane protein are not well understood. Here we show that the formation of the lipidic phases and the incorporation of the membrane protein into such materials can be separated experimentally. Specifically, we have investigated the effect of different initial monoolein-based lipid phase states on the crystallization behavior of the colored photosynthetic reaction center from Rhodobacter sphaeroides. We find that the detergent solubilized photosynthetic reaction center spontaneously inserts into and concentrates in the lipid matrix without any mixing, and that the initial lipid material phase state is irrelevant for productive crystallization. A substantial in-situ enrichment of the membrane protein to concentration levels that are otherwise unobtainable occurs in a thin layer on the surface of the lipidic material. These results have important practical applications and hence we suggest a simplified protocol for membrane protein crystallization within amphiphile rich materials, eliminating any specialized mixing tools to prepare crystallization experiments within lipidic cubic phases. Furthermore, by virtue of sampling a membrane protein concentration gradient within a single crystallization experiment, this crystallization technique is more robust and increases the efficiency of identifying productive crystallization parameters. Finally, we provide a model that explains the incorporation of the membrane protein from solution into the lipid phase via a portal lamellar phase. PMID:21909395

Single crystals of selected titanates and tungstates

NASA Technical Reports Server (NTRS)

Loiacono, G. M.

1972-01-01

The compound preparation and crystal growth of a number of mixed titanate compositions was investigated. None of the compounds studied were found to melt congruently and therefore, crystal growth was extremely difficult. Various single crystal preparation methods always resulted in mixed phases from which 1-2 mm size crystals could be separated. It is concluded from this study that before successful single crystal growth can be accomplished, a detailed study of the phase diagrams in each of the systems of interest must be completed.

Formation of an amorphous phase and its crystallization in the immiscible Nb-Zr system by mechanical alloying

NASA Astrophysics Data System (ADS)

Al-Aqeeli, N.; Suryanarayana, C.; Hussein, M. A.

2013-10-01

Mechanical alloying of binary Nb-Zr powder mixtures was carried out to evaluate the formation of metastable phases in this immiscible system. The milled powders were characterized for their constitution and structure by X-ray diffraction and transmission electron microscopy methods. It was shown that an amorphous phase had formed on milling the binary powder mixture for about 10 h and that it had crystallized on subsequent milling up to 50-70 h, referred to as mechanical crystallization. Thermodynamic and structural arguments have been presented to explain the formation of the amorphous phase and its subsequent crystallization.

Phase coexistence and domain configuration in Pb(Mg{sub 1/3}Nb{sub 2/3})O{sub 3}-0.34PbTiO{sub 3} single crystal revealed by synchrotron-based X-ray diffractive three-dimensional reciprocal space mapping and piezoresponse force microscopy

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

Wang, Ruixue; Yang, Bin, E-mail: binyang@hit.edu.cn; Sun, Enwei

The crystalline phases and domain configuration in the morphotropic phase boundary composition Pb(Mg{sub 1/3}Nb{sub 2/3})O{sub 3}-0.34PbTiO{sub 3} (PMN-0.34PT) single crystal have been investigated by synchrotron-based X-ray 3D Reciprocal Space Mapping (3D-RSM) and Piezoresponse Force Microscopy. The coexistence of tetragonal (T) and monoclinic M{sub C} phases in this PMN-0.34PT single crystal is confirmed. The affiliation of each diffraction spot in the 3D-RSM was identified with the assistance of qualitative simulation. Most importantly, the twinning structure between different domains in such a mixed phase PMN-PT crystal is firmly clarified, and the spatial distribution of different twin domains is demonstrated. In addition, themore » lattice parameters of T and M{sub C} phases in PMN-0.34PT single crystal as well as the tilting angles of crystal lattices caused by the interfacial lattice mismatch are determined.« less

Phase selection during crystallization of undercooled liquid eutectic lead-tin alloys

NASA Technical Reports Server (NTRS)

Fecht, H. J.

1991-01-01

During rapid solidification substantial amounts of undercooling are in general required for formation of metastable phases. Crystallization at varying levels of undercooling and melting of metastable phases were studied during slow cooling and heating of emulsified PB-Sn alloys. Besides the experimental demonstration of the reversibility of metastable phase equilibra, two different principal solidification paths have been identified and compared with the established metastable phase diagram and predictions from classical nucleation theory. The results suggest that the most probable solidification path is described by the 'step rule' resulting in the formation of metastable phases at low undercooling, whereas the stable eutectic phase mixture crystallizes without metastable phase formation at high undercooling.

Solid-Phase and Oscillating Solution Crystallization Behavior of (+)- and (-)-N-Methylephedrine.

PubMed

Tulashie, Samuel Kofi; Polenske, Daniel; Seidel-Morgenstern, Andreas; Lorenz, Heike

2016-11-01

This work involves the study of the solid-phase and solution crystallization behavior of the N-methylephedrine enantiomers. A systematic investigation of the melt phase diagram of the enantiomeric N-methylephedrine system was performed considering polymorphism. Two monotropically related modifications of the enantiomer were found. Solubilities and the ternary solubility phase diagrams of N-methylephedrine enantiomers in 2 solvents [isopropanol:water, 1:3 (Vol) and (2R, 3R)-diethyl tartrate] were determined in the temperature ranges between 15°C and 25°C, and 25°C and 40°C, respectively. Preferential nucleation and crystallization experiments at higher supersaturation leading to an unusual oscillatory crystallization behavior as well as a successful preferential crystallization experiment at lower supersaturation are presented and discussed. Copyright © 2016. Published by Elsevier Inc.

A multivariate and stochastic approach to identify key variables to rank dairy farms on profitability.

PubMed

Atzori, A S; Tedeschi, L O; Cannas, A

2013-05-01

The economic efficiency of dairy farms is the main goal of farmers. The objective of this work was to use routinely available information at the dairy farm level to develop an index of profitability to rank dairy farms and to assist the decision-making process of farmers to increase the economic efficiency of the entire system. A stochastic modeling approach was used to study the relationships between inputs and profitability (i.e., income over feed cost; IOFC) of dairy cattle farms. The IOFC was calculated as: milk revenue + value of male calves + culling revenue - herd feed costs. Two databases were created. The first one was a development database, which was created from technical and economic variables collected in 135 dairy farms. The second one was a synthetic database (sDB) created from 5,000 synthetic dairy farms using the Monte Carlo technique and based on the characteristics of the development database data. The sDB was used to develop a ranking index as follows: (1) principal component analysis (PCA), excluding IOFC, was used to identify principal components (sPC); and (2) coefficient estimates of a multiple regression of the IOFC on the sPC were obtained. Then, the eigenvectors of the sPC were used to compute the principal component values for the original 135 dairy farms that were used with the multiple regression coefficient estimates to predict IOFC (dRI; ranking index from development database). The dRI was used to rank the original 135 dairy farms. The PCA explained 77.6% of the sDB variability and 4 sPC were selected. The sPC were associated with herd profile, milk quality and payment, poor management, and reproduction based on the significant variables of the sPC. The mean IOFC in the sDB was 0.1377 ± 0.0162 euros per liter of milk (€/L). The dRI explained 81% of the variability of the IOFC calculated for the 135 original farms. When the number of farms below and above 1 standard deviation (SD) of the dRI were calculated, we found that 21 farms had dRI<-1 SD, 32 farms were between -1 SD and 0, 67 farms were between 0 and +1 SD, and 15 farms had dRI>+1 SD. The top 10% of the farms had a dRI greater than 0.170 €/L, whereas the bottom 10% farms had a dRI lower than 0.116 €/L. This stochastic approach allowed us to understand the relationships among the inputs of the studied dairy farms and to develop a ranking index for comparison purposes. The developed methodology may be improved by using more inputs at the dairy farm level and considering the actual cost to measure profitability. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

C.E.R.A. administered once monthly corrects and maintains stable hemoglobin levels in chronic kidney disease patients not on dialysis: the observational study MICENAS II.

PubMed

Martínez-Castelao, Alberto; Cases, Aleix; Coll, Elisabeth; Bonal, Jordi; Galceran, Josep M; Fort, Joan; Moreso, Francesc; Torregrosa, Vicente; Guirado, Lluís; Ruiz, Pilar

2015-01-01

C.E.R.A. (continuous erythropoietin receptor activator, pegilated-rHuEPO ß) corrects and maintains stable hemoglobin levels in once-monthly administration in chronic kidney disease (CKD) patients. The aim of this study was to evaluate the management of anemia with C.E.R.A. in CKD patients not on dialysis in the clinical setting. Two hundred seventy two anemic CKD patients not on dialysis treated with C.E.R.A. were included in this retrospective, observational, multicentric study during 2010. Demographical characteristics, analytical parameters concerning anemia, treatment data and iron status were recorded. C.E.R.A. achieved a good control of anemia in both naïve patients (mean Hemoglobin 11.6g/dL) and patients converted from a previous ESA (mean Hemoglobin 11.7g/dL). Most naïve patients received C.E.R.A. once monthly during the correction phase and required a low monthly dose (median dose 75 µg/month). The same median dose was required in patients converted from a previous ESA, and it was lower than recommended in the Summary of Product Characteristics (SPC). Iron status was adequate in 75% of anemic CKD patients, but only 50% of anemic patients with iron deficiency received iron supplementation. C.E.R.A. corrects and maintains stable hemoglobin levels in anemic CKD patients not on dialysis, requiring conversion doses lower than those recommended by the SPC, and achieving target hemoglobin levels with once-monthly dosing frequency both in naïve and converted patients.

The expression of HoxB5 and SPC in neonatal rat lung after exposure to fluoxetine.

PubMed

Taghizadeh, Razieh; Taghipour, Zahra; Karimi, Akbar; Shamsizadeh, Ali; Taghavi, Mohammad Mohsen; Shariati, Mahdi; Shabanizadeh, Ahmad; Jafari Naveh, Hamid Reza; Bidaki, Reza; Aminzadeh, Fariba

2016-01-01

Approximately 10% of pregnant women suffer from pregnancy-associated depression. Fluoxetine, as a selective serotonin reuptake inhibitor, is being employed as a therapy for depressive disorders. The present study aimed to determine the effects of fluoxetine on neonatal lung development. Thirty pregnant Wistar rats (weighing 200-250 g) were treated daily with 7 mg/kg fluoxetine from gestation day 0 to gestation day 21, via gavage. The control group received a similar volume of distilled water only. Following delivery, the newborns and their lungs were immediately weighed in both of the groups. The right lung was fixed for histological assessments while the left lung was used for evaluation of the expression of SPC and HoxB5 by the real-time polymerase chain reaction method. Results have indicated that even though the body weight and the number of neonatal rats in both groups were the same, the lung weight of neonates exposed to fluoxetine was significantly different compared to the control group ( P <0.05). Expression of both genes was increased, nonetheless, only elevation of HoxB5 was significant ( P <0.05). Histological studies demonstrated that lung tissue in the fluoxetine treatment group morphologically appears to be similar to the pseudoglandular phase, whereas the control group lungs experienced more development. According to the upregulated expression of HoxB5 concerning histological findings, results of the present study showed that fluoxetine can influence lung growth and may in turn lead to delay in lung development. So establishment of studies to identify the effects of antidepressant drugs during pregnancy is deserved.

Switching plastic crystals of colloidal rods with electric fields

PubMed Central

Liu, Bing; Besseling, Thijs H.; Hermes, Michiel; Demirörs, Ahmet F.; Imhof, Arnout; van Blaaderen, Alfons

2014-01-01

When a crystal melts into a liquid both long-ranged positional and orientational order are lost, and long-time translational and rotational self-diffusion appear. Sometimes, these properties do not change at once, but in stages, allowing states of matter such as liquid crystals or plastic crystals with unique combinations of properties. Plastic crystals/glasses are characterized by long-ranged positional order/frozen-in-disorder but short-ranged orientational order, which is dynamic. Here we show by quantitative three-dimensional studies that charged rod-like colloidal particles form three-dimensional plastic crystals and glasses if their repulsions extend significantly beyond their length. These plastic phases can be reversibly switched to full crystals by an electric field. These new phases provide insight into the role of rotations in phase behaviour and could be useful for photonic applications. PMID:24446033

Switching plastic crystals of colloidal rods with electric fields

NASA Astrophysics Data System (ADS)

Liu, Bing; Besseling, Thijs H.; Hermes, Michiel; Demirörs, Ahmet F.; Imhof, Arnout; van Blaaderen, Alfons

2014-01-01

When a crystal melts into a liquid both long-ranged positional and orientational order are lost, and long-time translational and rotational self-diffusion appear. Sometimes, these properties do not change at once, but in stages, allowing states of matter such as liquid crystals or plastic crystals with unique combinations of properties. Plastic crystals/glasses are characterized by long-ranged positional order/frozen-in-disorder but short-ranged orientational order, which is dynamic. Here we show by quantitative three-dimensional studies that charged rod-like colloidal particles form three-dimensional plastic crystals and glasses if their repulsions extend significantly beyond their length. These plastic phases can be reversibly switched to full crystals by an electric field. These new phases provide insight into the role of rotations in phase behaviour and could be useful for photonic applications.

Monoclinic nanodomains in morphotropic phase boundary Pb(Mg{sub 1/3}Nb{sub 2/3})O{sub 3}–PbTiO{sub 3}

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

Sato, Y., E-mail: y-sato@sigma.t.u-tokyo.ac.jp; Hirayama, T.; Ikuhara, Y.

2014-02-24

Crystalline structure is a fundamental characteristic of many materials, and drastic changes in properties may accompany crystal phase transitions. A prominent example of this is the morphotropic phase boundary of (Pb(Mg{sub 1/3}Nb{sub 2/3})O{sub 3}-PbTiO{sub 3}) single crystal, a region that exhibits a high piezoelectric effect. Although the highest piezoelectricity is often attributed to a monoclinic crystal phase, formation of ferroelectric nanodomains (NDs) complicates understanding of this crystal structure. In this Letter, we report dedicated transmission electron microscopy and electron diffraction analysis to understand the crystal structure at the ND level. Splitting of diffraction spots, caused by very small lattice distortionmore » in the NDs, is important to understanding crystal structure and has been unambiguously observed. The results can be explained by monoclinic phase NDs. Combining these results with our previous findings on ND dynamics [Sato et al. Phys. Rev. Lett. 107, 187601 (2011)], monoclinic NDs can potentially make a considerable contribution to the piezoelectricity in these materials.« less

Destabilization of mayonnaise induced by lipid crystallization upon freezing.

PubMed

Miyagawa, Yayoi; Ogawa, Takenobu; Nakagawa, Kyuya; Adachi, Shuji

2016-01-01

The thermal and rheological history of mayonnaise during freezing and its dispersion stability after the freeze-thaw process were investigated. Mayonnaise was cooled to freeze and stored at -20 to -40 °C while monitoring the temperature; penetration tests were conducted on the mayonnaise, which was sampled at selected times during isothermal storage at -20 °C. Significant increases in the temperature and stress values due to water-phase crystallization and subsequent oil-phase crystallization were observed. The water phase crystallized during the cooling step in all the tested mayonnaise samples. The oil phases of the prepared mayonnaise (with rapeseed oil) and commercial mayonnaise crystallized during isothermal storage after 6 and 4 h, respectively, at -20 °C. The dispersion stability was evaluated from the separation ratio, which was defined as the weight ratio of separated oil after centrifuging to the total amount of oil in the commercial mayonnaise. The separation ratio rapidly increased after 4 h of freezing. This result suggests that crystallization of the oil phase is strongly related to the dispersion stability of mayonnaise.

Study of liquid?liquid demixing from drug solution

NASA Astrophysics Data System (ADS)

Lafferrère, Laurent; Hoff, Christian; Veesler, Stéphane

2004-09-01

In pharmaceutical industry, a deep understanding of the phase diagram is required in design of crystallization processes. We have investigated the phase diagram of a pharmaceutical compound (C 35H 41Cl 2N 3O 2) in a mixture of ethanol/water. This phase diagram exhibits a solid-solid (polymorphism) and a liquid-liquid-phase separation (LLPS) as a function of temperature and drug substance concentration. This study focuses on the LLPS which is metastable with respect to the crystallization of the two polymorphs FI and FII of C 35H 41Cl 2N 3O 2 in an ethanol/water mixture. The LLPS is metastable towards the solubility curve on the whole solvent-solute concentrations and temperature range studied. The LLPS occurred within the metastable zone for crystallization. In our experiments the liquid-liquid-phase transition prevented the drug from crystallizing, while it changed the medium and the conditions of crystallization, which consequently affected the process. The coexistence curves for the liquid phases, also named TL-L boundary, and the spinodal line were measured for a ternary mixture of water-drug-ethanol at atmospheric pressure over a temperature range of 10-50°C. This temperature range corresponds to that used in the crystallization process. Static Light Scattering, HPLC measurements and Karl-Fischer titration were applied to investigate the drug-phase diagram. The isoplethe section of the phase diagram exhibits four regions: one homogeneous (one liquid) and three two-phases (two regions with one liquid+one solid and one region with two liquids), the two solids phases being two polymorphs.

Interface dynamics and crystal phase switching in GaAs nanowires

NASA Astrophysics Data System (ADS)

Jacobsson, Daniel; Panciera, Federico; Tersoff, Jerry; Reuter, Mark C.; Lehmann, Sebastian; Hofmann, Stephan; Dick, Kimberly A.; Ross, Frances M.

2016-03-01

Controlled formation of non-equilibrium crystal structures is one of the most important challenges in crystal growth. Catalytically grown nanowires are ideal systems for studying the fundamental physics of phase selection, and could lead to new electronic applications based on the engineering of crystal phases. Here we image gallium arsenide (GaAs) nanowires during growth as they switch between phases as a result of varying growth conditions. We find clear differences between the growth dynamics of the phases, including differences in interface morphology, step flow and catalyst geometry. We explain these differences, and the phase selection, using a model that relates the catalyst volume, the contact angle at the trijunction (the point at which solid, liquid and vapour meet) and the nucleation site of each new layer of GaAs. This model allows us to predict the conditions under which each phase should be observed, and use these predictions to design GaAs heterostructures. These results could apply to phase selection in other nanowire systems.

Interface dynamics and crystal phase switching in GaAs nanowires.

PubMed

Jacobsson, Daniel; Panciera, Federico; Tersoff, Jerry; Reuter, Mark C; Lehmann, Sebastian; Hofmann, Stephan; Dick, Kimberly A; Ross, Frances M

2016-03-17

Controlled formation of non-equilibrium crystal structures is one of the most important challenges in crystal growth. Catalytically grown nanowires are ideal systems for studying the fundamental physics of phase selection, and could lead to new electronic applications based on the engineering of crystal phases. Here we image gallium arsenide (GaAs) nanowires during growth as they switch between phases as a result of varying growth conditions. We find clear differences between the growth dynamics of the phases, including differences in interface morphology, step flow and catalyst geometry. We explain these differences, and the phase selection, using a model that relates the catalyst volume, the contact angle at the trijunction (the point at which solid, liquid and vapour meet) and the nucleation site of each new layer of GaAs. This model allows us to predict the conditions under which each phase should be observed, and use these predictions to design GaAs heterostructures. These results could apply to phase selection in other nanowire systems.

Intermediate phases in [111]- and [001]-oriented PbMg1/3Nb2/3O3-29PbTiO3 single crystals

NASA Astrophysics Data System (ADS)

Kamzina, L. S.

2017-09-01

Phase transformations in [111]- and [001]-oriented PbMg1/3Nb2/3O3-29PbTiO3 single crystals have been studied using dielectric and optical measurements before and after applying an electric field. It is shown that the subsequence of phase transitions rhombohedral ( R)—tetragonal ( T)—cubic ( C) phases is observed in nonpolarized samples of both orientations as temperature increases. In the [111]-oriented crystal, an additional intermediate monoclinic phase (it is possible, M a ) is induced after preliminary polarization at room temperature and the R- M a - T- C phase transitions are observed on heating. In the [001]-oriented crystal, after its polarization, the monoclinic phase forms instead of the rhombohedral phase even at room temperature and the M a - T- C transitions occur on heating. The results are discussed from the point of view of the existence polar nanoregions with different local symmetries in a glasslike matrix.

The effect of deuteration and doping on the phase transition temperature of grown glycine phosphite single crystals

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

Perumal, R., E-mail: perumal-cgc@yahoo.co.uk; Chandru, A. Lakshmi; Babu, S. Moorthy

The Glycinium Phosphite (GPI) compound is a representative of hydrogen-bonded ferroelectric crystals. The ordering of protons could be expected below the room temperature (225 K). Crystals grown from the milipore water as well as deuterated solvents respectively. The corresponding hydrogen bond distance was stretched out due to the effect of isotopic substitution that increase the phase transition temperature. Further to improve the phase transition temperature, GPI crystal was doped with organic complexing agent and various metals and the obtained results are presented.

Glass formation and crystallization in high-temperature glass-ceramics and Si3N4

NASA Technical Reports Server (NTRS)

Drummond, Charles H., III

1991-01-01

The softening of glassy grain boundaries in ceramic matrix composites and Si3N4 at high temperatures reduces mechanical strength and the upper-use temperature. By crystallizing this glass to a more refractory crystalline phase, a material which performs at higher temperatures may result. Three systems were examined: a cordierite composition with ZrO2 as a nucleating agent; celsian compositions; and yttrium silicate glasses both in bulk and intergranular in Si3N4. For the cordierite compositions, a series of metastable phases was obtained. The crystallization of these compositions was summarized in terms of metastable ternary isothermal sections. Zircon formed at the expense of ZrO2 and spinel. In SiC composites, the transformations were slower. In celsian, two polymorphs were crystallized. One phase, hexacelsian, which always crystallized, even when metastable, had an undesirable volume change. The other phase, celsian, was very difficult to crystallize. In yttrium silicate bulk glasses, similar in composition to the intergranular glass in Si3N4, a number of polymorphs of Y2Si2O7 were crystallized. The conditions under which these polymorphs formed are compared with crystallization in Si3N4.

Effect of anisotropic MoS2 nanoparticles on the blue phase range of a chiral liquid crystal.

PubMed

Lavrič, Marta; Cordoyiannis, George; Kralj, Samo; Tzitzios, Vassilios; Nounesis, George; Kutnjak, Zdravko

2013-08-01

Liquid-crystalline blue phases are attracting significant interest due to their potential for applications related to tunable photonic crystals and fast optical displays. In this work a brief theoretical model is presented accounting for the impact of anisotropic nanoparticles on the blue phase stability region. This model is tested by means of high-resolution calorimetric and optical measurements of the effect of anisotropic, surface-functionalized MoS2 nanoparticles on the blue phase range of a chiral liquid crystal. The addition of these nanoparticles effectively increases the temperature range of blue phases and especially the cubic structure of blue phase I.

Self-consistent phonon theory of the crystallization and elasticity of attractive hard spheres.

PubMed

Shin, Homin; Schweizer, Kenneth S

2013-02-28

We propose an Einstein-solid, self-consistent phonon theory for the crystal phase of hard spheres that interact via short-range attractions. The approach is first tested against the known behavior of hard spheres, and then applied to homogeneous particles that interact via short-range square well attractions and the Baxter adhesive hard sphere model. Given the crystal symmetry, packing fraction, and strength and range of attractive interactions, an effective harmonic potential experienced by a particle confined to its Wigner-Seitz cell and corresponding mean square vibrational amplitude are self-consistently calculated. The crystal free energy is then computed and, using separate information about the fluid phase free energy, phase diagrams constructed, including a first-order solid-solid phase transition and its associated critical point. The simple theory qualitatively captures all the many distinctive features of the phase diagram (critical and triple point, crystal-fluid re-entrancy, low-density coexistence curve) as a function of attraction range, and overall is in good semi-quantitative agreement with simulation. Knowledge of the particle localization length allows the crystal shear modulus to be estimated based on elementary ideas. Excellent predictions are obtained for the hard sphere crystal. Expanded and condensed face-centered cubic crystals are found to have qualitatively different elastic responses to varying attraction strength or temperature. As temperature increases, the expanded entropic solid stiffens, while the energy-controlled, fully-bonded dense solid softens.

Control of composition and crystallinity in hydroxyapatite films deposited by electron cyclotron resonance plasma sputtering

NASA Astrophysics Data System (ADS)

Akazawa, Housei; Ueno, Yuko

2014-01-01

Hydroxyapatite (HAp) films were deposited by electron cyclotron resonance plasma sputtering under a simultaneous flow of H2O vapor gas. Crystallization during sputter-deposition at elevated temperatures and solid-phase crystallization of amorphous films were compared in terms of film properties. When HAp films were deposited with Ar sputtering gas at temperatures above 460 °C, CaO byproducts precipitated with HAp crystallites. Using Xe instead of Ar resolved the compositional problem, yielding a single HAp phase. Preferentially c-axis-oriented HAp films were obtained at substrate temperatures between 460 and 500 °C and H2O pressures higher than 1×10-2 Pa. The absorption signal of the asymmetric stretching mode of the PO43- unit (ν3) in the Fourier-transform infrared absorption (FT-IR) spectra was the narrowest for films as-crystallized during deposition with Xe, but widest for solid-phase crystallized films. While the symmetric stretching mode of PO43- (ν1) is theoretically IR-inactive, this signal emerged in the FT-IR spectra of solid-phase crystallized films, but was absent for as-crystallized films, indicating superior crystallinity for the latter. The Raman scattering signal corresponding to ν1 PO43- sensitively reflected this crystallinity. The surface hardness of as-crystallized films evaluated by a pencil hardness test was higher than that of solid-phase crystallized films.

Studies of Nucleation, Growth, Specific Heat, and Viscosity of Undercooled Melts of Quasicrystals and Polytetrahedral-Phase-Forming Alloys

NASA Technical Reports Server (NTRS)

Kelton, K. F.; Croat, T. K.; Gangopadhyay, A.; Holland-Moritz, D.; Hyers, Robert W.; Rathz, Thomas J.; Robinson, Michael B.; Rogers, Jan R.

2001-01-01

Undercooling experiments and thermal physical property measurements of metallic alloys on the International Space Station (ISS) are planned. This recently-funded research focuses on fundamental issues of the formation and structure of highly-ordered non-crystallographic phases (quasicrystals) and related crystal phases (crystal approximants), and the connections between the atomic structures of these phases and those of liquids and glasses. It extends studies made previously by us of the composition dependence of crystal nucleation processes in silicate and metallic glasses, to the case of nucleation from the liquid phase. Motivating results from rf-levitation and drop-tube measurements of the undercooling of Ti/Zr-based liquids that form quasicrystals and crystal approximants are discussed. Preliminary measurements by electrostatic levitation (ESL) are presented.

Phase diagram of a symmetric electron-hole bilayer system: a variational Monte Carlo study.

PubMed

Sharma, Rajesh O; Saini, L K; Bahuguna, Bhagwati Prasad

2018-05-10

We study the phase diagram of a symmetric electron-hole bilayer system at absolute zero temperature and in zero magnetic field within the quantum Monte Carlo approach. In particular, we conduct variational Monte Carlo simulations for various phases, i.e. the paramagnetic fluid phase, the ferromagnetic fluid phase, the anti-ferromagnetic Wigner crystal phase, the ferromagnetic Wigner crystal phase and the excitonic phase, to estimate the ground-state energy at different values of in-layer density and inter-layer spacing. Slater-Jastrow style trial wave functions, with single-particle orbitals appropriate for different phases, are used to construct the phase diagram in the (r s , d) plane by finding the relative stability of trial wave functions. At very small layer separations, we find that the fluid phases are stable, with the paramagnetic fluid phase being particularly stable at [Formula: see text] and the ferromagnetic fluid phase being particularly stable at [Formula: see text]. As the layer spacing increases, we first find that there is a phase transition from the ferromagnetic fluid phase to the ferromagnetic Wigner crystal phase when d reaches 0.4 a.u. at r s   =  20, and before there is a return to the ferromagnetic fluid phase when d approaches 1 a.u. However, for r s   <  20 and [Formula: see text] a.u., the excitonic phase is found to be stable. We do not find that the anti-ferromagnetic Wigner crystal is stable over the considered range of r s and d. We also find that as r s increases, the critical layer separations for Wigner crystallization increase.

Glassy phases and driven response of the phase-field-crystal model with random pinning.

PubMed

Granato, E; Ramos, J A P; Achim, C V; Lehikoinen, J; Ying, S C; Ala-Nissila, T; Elder, K R

2011-09-01

We study the structural correlations and the nonlinear response to a driving force of a two-dimensional phase-field-crystal model with random pinning. The model provides an effective continuous description of lattice systems in the presence of disordered external pinning centers, allowing for both elastic and plastic deformations. We find that the phase-field crystal with disorder assumes an amorphous glassy ground state, with only short-ranged positional and orientational correlations, even in the limit of weak disorder. Under increasing driving force, the pinned amorphous-glass phase evolves into a moving plastic-flow phase and then, finally, a moving smectic phase. The transverse response of the moving smectic phase shows a vanishing transverse critical force for increasing system sizes.

Vapor-crystal phase transition in synthesis of paracetamol films by vacuum evaporation and condensation

NASA Astrophysics Data System (ADS)

Belyaev, A. P.; Rubets, V. P.; Antipov, V. V.; Bordei, N. S.; Zarembo, V. I.

2014-03-01

We report on the structural and technological investigations of the vapor-crystal phase transition during synthesis of paracetamol films of the monoclinic system by vacuum evaporation and condensation in the temperature range 220-320 K. The complex nature of the transformation accompanied by the formation of a gel-like phase is revealed. The results are interpreted using a model according to which the vapor-crystal phase transition is not a simple first-order phase transition, but is a nonlinear superposition of two phase transitions: a first-order transition with a change in density and a second-order phase transition with a change in ordering. Micrographs of the surface of the films are obtained at different phases of formation.

Investigation of crystalline morphology in poly (ether ether ketone) using dielectric relaxation spectroscopy

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

Kalika, D.S.; Krishnaswamy, R.K.

1993-12-31

The relaxation behavior of poly (ether ether ketone) [PEEK] has been investigated using dielectric relaxation spectroscopy; the glass-rubber ({alpha}) relaxation and a sub-glass ({beta}) relaxation were examined for the amorphous material and both cold-crystallized and melt-crystallized specimens. Analysis of the data using the Cole-Cole modification of the Debye equation allowed determination of the dielectric relaxation strength and relaxation broadening parameter for both transitions as a function of material crystallization history. The crystallized specimens displayed a positive offset in isochronal loss temperature for both the {alpha} and {beta} relaxations, with the {alpha} relaxation broadened significantly. The measured dipolar response was interpretedmore » using a three-phase morphological model encompassing a crystalline phase, a mobile amorphous phase, and a rigid amorphous phase. Determination of phase fractions based on dipolar mobilization across the glass-rubber relaxation revealed a finite rigid amorphous phase fraction for both the cold-crystallized specimens which was relatively insensitive to thermal history and degree of crystallinity (W{sub RAP}40.20).« less

Phase separation and crystallization process of amorphous Fe{sub 78}B{sub 12}Si{sub 9}Ni{sub 1} alloy

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

Mukhgalin, V. V.; Lad’yanov, V. I.

2015-08-17

The influence of the melt heat treatment on the structure and crystallization process of the rapidly quenched amorphous Fe{sub 78}B{sub 12}Si{sub 9}Ni{sub 1} alloys have been investigated by means of x-ray diffraction, DSC and TEM. Amorphous phase separation has been observed in the alloys quenched after the preliminary high temperature heat treatment of the liquid alloy (heating above 1400°C). Comparative analysis of the pair distribution functions demonstrates that this phase separation accompanied by a changes in the local atomic arrangement. It has been found that crystallization process at heating is strongly dependent on the initial amorphous phase structure - homogeneousmore » or phase separated. In the last case crystallization goes through the formation of a new metastable hexagonal phase [a=12.2849(9) Ǻ, c=7.6657(8) Ǻ]. At the same time the activation energy for crystallization (Ea) reduces from 555 to 475 kJ mole{sup −1}.« less

Optical Diagnostics of Solution Crystal Growth

NASA Technical Reports Server (NTRS)

Kim, Yongkee; Reddy, B. R.; George, T. G.; Lal, R. B.

1996-01-01

Non-contact optical techniques such as, optical heterodyne, ellipsometry and interferometry, for real time in-situ monitoring of solution crystal growth are demonstrated. Optical heterodyne technique has the capability of measuring the growth rate as small as 1A/sec. In a typical Michelson interferometer set up, the crystal is illuminated by a Zeeman laser with frequency omega(sub 1) and the reference beam with frequency omega(sub 2). As the crystal grows, the phase of the rf signal changes with respect to the reference beam and this phase change is related to the crystal growth rate. This technique is demonstrated with two examples: (1) by measuring the copper tip expansion/shrinkage rate and (2) by measuring the crystal growth rate of L-Arginine Phosphate (LAP). The first test shows that the expansion/shrinkage rate of copper tip was fast in the beginning, and gets slower as the expansion begins to stabilize with time. In crystal growth, the phase change due the crystal growth is measured using a phase meter and a strip chart recorder. Our experimental results indicate a varied growth rate from 69.4 to 92.6A per sec. The ellipsometer is used to study the crystal growth interface. From these measurements and a theoretical modeling of the interface, the various optical parameters can be deduced. Interferometry can also be used to measure the growth rate and concentration gradient in the vicinity of the crystal.

Directed Self-Assembly of Liquid Crystalline Blue-Phases into Ideal Single-Crystals

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

Martinez-Gonzalez, Jose A.; Li, Xiao; Sadati, Monirosadat

Chiral nematic liquid crystals are known to form blue phases—liquid states of matter that exhibit ordered cubic arrangements of topological defects. Blue-phase specimens, however, are generally polycrystalline, consisting of randomly oriented domains that limit their performance in applications. A strategy that relies on nano-patterned substrates is presented here for preparation of stable, macroscopic single-crystal blue-phase materials. Different template designs are conceived to exert control over different planes of the blue-phase lattice orientation with respect to the underlying substrate. Experiments are then used to demonstrate that it is indeed possible to create stable single-crystal blue-phase domains with the desired orientation overmore » large regions. Lastly, these results provide a potential avenue to fully exploit the electro-optical properties of blue phases, which have been hindered by the existence of grain boundaries.« less

Temperature tuning of lasing emission from dye-doped liquid crystal at intermediate twisted phase

NASA Astrophysics Data System (ADS)

Liao, Kuan-Cheng; Lin, Ja-Hon; Jian, Li-Hao; Chen, Yao-Hui; Wu, Jin-Jei

2015-07-01

Temperature tuning of lasing emission from dye-doped cholesteric liquid crystal (CLC) at intermediate twisted phase has been demonstrated in this work. With heavily doping of 42.5% chiral molecules into the nematic liquid crystals, the shifts of photonic bandgap versus temperature is obviously as thermal controlling of the sample below the certain value. By the differential scanning calorimetr measuremet, we demonstrate the phase transition from the CLC to the smectic phase when the temperature is lowered to be about 15°C. Between CLC and smectic phase, the liquid crystal mixtures are operated at intermediate twisted phase that can be used the temperature related refractive mirror. After pump by the Q-switched Nd:YAG laser, the lasing emission from this dye doped LC mixtures has been demonstrated whose emission wavelength can be tuned from 566 to 637 nm with 1.4°C variation.

Directed Self-Assembly of Liquid Crystalline Blue-Phases into Ideal Single-Crystals

DOE PAGES

Martinez-Gonzalez, Jose A.; Li, Xiao; Sadati, Monirosadat; ...

2017-06-16

Chiral nematic liquid crystals are known to form blue phases—liquid states of matter that exhibit ordered cubic arrangements of topological defects. Blue-phase specimens, however, are generally polycrystalline, consisting of randomly oriented domains that limit their performance in applications. A strategy that relies on nano-patterned substrates is presented here for preparation of stable, macroscopic single-crystal blue-phase materials. Different template designs are conceived to exert control over different planes of the blue-phase lattice orientation with respect to the underlying substrate. Experiments are then used to demonstrate that it is indeed possible to create stable single-crystal blue-phase domains with the desired orientation overmore » large regions. Lastly, these results provide a potential avenue to fully exploit the electro-optical properties of blue phases, which have been hindered by the existence of grain boundaries.« less

Controllable fabrication of copper phthalocyanine nanostructure crystals.

PubMed

Liu, Fangmei; Sun, Jia; Xiao, Si; Huang, Wenglong; Tao, Shaohua; Zhang, Yi; Gao, Yongli; Yang, Junliang

2015-06-05

Copper phthalocyanine (CuPc) nanostructure crystals, including nanoflower, nanoribbon, and nanowire, were controllably fabricated by temperature gradient physical vapor deposition (TG-PVD) through controlling the growth parameters. In a controllable growth system with carrier gas N2, nanoflower, nanoribbon, and nanowire crystals were formed in a high-temperature zone, medium-temperature zone, and low-temperature zone, respectively. They were proved to be β-phase, coexist of α-phase and β-phase, and α-phase respectively based on x-ray diffraction results. Furthermore, ultralong CuPc nanowires up to several millimeters could be fabricated by TG-PVD without carrier gas, and they were well-aligned to form large-area CuPc nanowire crystal arrays by the Langmuir-Blodgett method. The nanostructure crystals showed unusual optical absorption spectra from the ultraviolet-visible to near-infrared range, which was explained by the diffraction and scattering caused by the wavelength-sized nanostructures. These CuPc nanostructure crystals show potential applications in organic electronic and optoelectronic devices.

Ikaite pseudomorphs in the Zaire deep-sea fan: An intermediate between calcite and porous calcite

NASA Astrophysics Data System (ADS)

Jansen, J. H. F.; Woensdregt, C. F.; Kooistra, M. J.; van der Gaast, S. J.

1987-03-01

Translucent brown aggregates of calcium-carbonate crystals have been found in cores from the Zaire deep-sea fan (west equatorial Africa). The aggregates are well preserved but very friable. Upon storage they become yellowish white and cloudy and release water. Chemical, mineralogical (XRD), petrographical, crystal-morphological, and stable-isotope data demonstrate that the crystals have passed through three phases: (1) an authigenic carbonate phase, probably calcium carbonate, which is represented by the external habit of the present crystals; (2) a translucent brown ikaite phase (CaCO3·6H2O), unstable at temperatures above 5 °C; and (3) a phase consisting of calcite microcrystals that are poorly cemented and form a porous mass within the crystal form of the morphologically unchanged first phase. The transformation from the first phase into ikaite was probably a kinetic replacement. The transformation from ikaite into the third phase occurred because of storage at room temperature. The presence of ikaite is indicative of a low-temperature, anaerobic, organic-carbon-rich marine environment. Ikaite is probably the precursor of a great number of porous calcite pseudomorphs, and possibly also of many marine authigenic microcrystalline carbonate nodules.

Third harmonic frequency generation by type-I critically phase-matched LiB3O5 crystal by means of optically active quartz crystal.

PubMed

Gapontsev, Valentin P; Tyrtyshnyy, Valentin A; Vershinin, Oleg I; Davydov, Boris L; Oulianov, Dmitri A

2013-02-11

We present a method of third harmonic generation at 355 nm by frequency mixing of fundamental and second harmonic radiation of an ytterbium nanosecond pulsed all-fiber laser in a type-I phase-matched LiB(3)O(5) (LBO) crystal where originally orthogonal polarization planes of the fundamental and second harmonic beams are aligned by an optically active quartz crystal. 8 W of ultraviolet light at 355 nm were achieved with 40% conversion efficiency from 1064 nm radiation. The conversion efficiency obtained in a type-I phase-matched LBO THG crystal was 1.6 times higher than the one achieved in a type-II LBO crystal at similar experimental conditions. In comparison to half-wave plates traditionally used for polarization alignment the optically active quartz crystal has much lower temperature dependence and requires simpler optical alignment.

Large Electro-Optic Kerr Effect in Ionic Liquid Crystals: Connecting Features of Liquid Crystals and Polyelectrolytes.

PubMed

Schlick, M Christian; Kapernaum, Nadia; Neidhardt, Manuel M; Wöhrle, Tobias; Stöckl, Yannick; Laschat, Sabine; Giesselmann, Frank

2018-06-06

The electro-optic Kerr effect in simple dipolar fluids such as nitrobenzene has been widely applied in electro-optical phase modulators and light shutters. In 2005, the discovery of the large Kerr effect in liquid-crystalline blue phases (Y. Hisakado et al., Adv. Mater. 2005, 17, 96-98.) gave new directions to the search for advanced Kerr effect materials. Even though the Kerr effect is present in all transparent and optically isotropic media, it is well known that the effect can be anomalously large in complex fluids, namely in the isotropic phase of liquid crystals or in polyelectrolyte solutions. Herein, it is shown that the Kerr effect in the isotropic phase of ionic liquid crystals combines the effective counterion polarization mechanism found in polyelectrolytes and the unique pretransitional growth of the Kerr constant found in the isotropic phase of nematic liquid crystals. Maximum Kerr constants in the order of several 10 -11  m V -2 (ten times higher than the Kerr constant of the toxic nitrobenzene and less temperature sensitive than Kerr constants of nematic liquid crystals) make ionic liquid crystals attractive as new class of functional materials in low-speed Kerr effect applications. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Reentrant equilibrium disordering in nanoparticle–polymer mixtures

DOE PAGES

Meng, Dong; Kumar, Sanat K.; Grest, Gary S.; ...

2017-01-31

A large body of experimental work has established that athermal colloid/polymer mixtures undergo a sequence of transitions from a disordered fluid state to a colloidal crystal to a second disordered phase with increasing polymer concentration. These transitions are driven by polymer-mediated interparticle attraction, which is a function of both the polymer density and size. It has been posited that the disordered state at high polymer density is a consequence of strong interparticle attractions that kinetically inhibit the formation of the colloidal crystal, i.e., the formation of a non-equilibrium gel phase interferes with crystallization. Here we use molecular dynamics simulations andmore » density functional theory on polymers and nanoparticles (NPs) of comparable size and show that the crystal-disordered phase coexistence at high polymer density for sufficiently long chains corresponds to an equilibrium thermodynamic phase transition. While the crystal is, indeed, stabilized at intermediate polymer density by polymer-induced intercolloid attractions, it is destabilized at higher densities because long chains lose significant configurational entropy when they are forced to occupy all of the crystal voids. Finally, our results are in quantitative agreement with existing experimental data and show that, at least in the nanoparticle limit of sufficiently small colloidal particles, the crystal phase only has a modest range of thermodynamic stability.« less

Apparatus and methods for using achromatic phase matching at high orders of dispersion

DOEpatents

Richman, Bruce; Trebino, Rick; Bisson, Scott; Sidick, Erkin

2001-01-01

Achromatic phase-matching (APM) is used for efficiently multiplying the frequency of broad bandwidth light by using a nonlinear optical medium comprising a second-harmonic generation (SHG) crystal. Stationary optical elements whose configuration, properties, and arrangement have been optimized to match the dispersion characteristics of the SHG crystal to at least the second order. These elements include a plurality of prismatic elements for directing an input light beam onto the SHG crystal such that each ray wavelength is aligned to match the phase-matching angle for the crystal at each wavelength of light to at least the second order and such that every ray wavelength overlap within the crystal.

Single Photon Counting Performance and Noise Analysis of CMOS SPAD-Based Image Sensors

PubMed Central

Dutton, Neale A. W.; Gyongy, Istvan; Parmesan, Luca; Henderson, Robert K.

2016-01-01

SPAD-based solid state CMOS image sensors utilising analogue integrators have attained deep sub-electron read noise (DSERN) permitting single photon counting (SPC) imaging. A new method is proposed to determine the read noise in DSERN image sensors by evaluating the peak separation and width (PSW) of single photon peaks in a photon counting histogram (PCH). The technique is used to identify and analyse cumulative noise in analogue integrating SPC SPAD-based pixels. The DSERN of our SPAD image sensor is exploited to confirm recent multi-photon threshold quanta image sensor (QIS) theory. Finally, various single and multiple photon spatio-temporal oversampling techniques are reviewed. PMID:27447643

Molecular dynamics simulations to study the solvent influence on protein structure

NASA Astrophysics Data System (ADS)

Dominguez, Hector

2016-05-01

Molecular simulations were carried out to study the influence of different water models in two protein systems. Most of the solvents used in protein simulations, e.g., SPC/E or TIP3P, fail to reproduce the bulk water static dielectric constant. Recently a new water model, TIP4P/ɛ, which reproduces the experimental dielectric constant was reported. Therefore, simulations for two different proteins, Lysozyme and Ubiquitin with SPC/E, TIP3P and TIP4P/ɛ solvents were carried out. Dielectric constants and structural properties were calculated and comparisons were conducted. The structural properties between the three models are very similar, however, the dielectric constants are different in each case.

Optically addressed and submillisecond response phase only liquid crystal spatial light modulator

NASA Astrophysics Data System (ADS)

Zhao, Xiangjie; Duan, Jiazhu; Zhang, Dayong; Luo, Yongquan

2014-10-01

Liquid crystal based phase only spatial light modulator has attracted many research interests since last decades because of its superior advantage. Until now the liquid crystal spatial light modulator has been applied in many fields, but the response speed of nematic LC limited its further application. In this paper, an optically addressed phase only LC spatial light modulator was proposed based on polymer network liquid crystal. Morphology effect on the light scattering of PNLC was studied, which was mainly consisted of fiber and fiber bundles. The morphology nearly determined the light scattering and electro-optical property. Due to the high threshold voltage, to address the PNLC phase modulator was also concerned. Optical addressing method was proposed, in which BSO crystal was selected to replace one of the glass substrate. The response speed of PNLC was so fast that the reorientation of liquid crystal director will follow the change of effective voltage applied on LC layer, which was related with the voltage signal and especially with electron transport of photo-induced carriers due to diffusion and drift. The on state dynamic response of phase change was investigated. Based on this device, beam steering was also achieved by loading 488nm laser strip on the optical addressed phase only spatial light modulator.

Orientation of liquid crystalline blue phases on unidirectionally orienting surfaces

NASA Astrophysics Data System (ADS)

Takahashi, Misaki; Ohkawa, Takuma; Yoshida, Hiroyuki; Fukuda, Jun-ichi; Kikuchi, Hirostugu; Ozaki, Masanori

2018-03-01

Liquid crystalline cholesteric blue phases (BPs) continue to attract interest due to their fast response times and quasi-polarization-independent phase modulation capabilities. Various approaches have recently been proposed to control the crystal orientation of BPs on substrates; however, their basic orientation properties on standard, unidirectionally orienting alignment layers have not been investigated in detail. Through analysis of the azimuthal orientation of Kossel diagrams, we study the 3D crystal orientation of a BP material—with a phase sequence of cholesteric, BP I, and BP II—on unidirectionally orienting surfaces prepared using two methods: rubbing and photoalignment. BP II grown from the isotropic phase is sensitive to surface conditions, with different crystal planes orienting on the two substrates. On the other hand, strong thermal hysteresis is observed in BPs grown through a different liquid crystal phase, implying that the preceding structure determines the orientation. More specifically, the BP II-I transition is accompanied by a rotation of the crystal such that the crystal direction defined by certain low-value Miller indices transform into different directions, and within the allowed rotations, different azimuthal configurations are obtained in the same cell depending on the thermal process. Our findings demonstrate that, for the alignment control of BPs, the thermal process is as important as the properties of the alignment layer.

Impact of the phase-mismatch in the SHG crystal and consequential self-action of the fundamental wave by cascaded second-order effects on the THG efficiency of a Q-switched 1342 nm Nd:YVO₄ laser.

PubMed

Koch, Peter; Bartschke, Juergen; L'huillier, Johannes A

2015-05-18

We report on the influence of self-focusing and self-defocusing in the phase-mismatched frequency doubling crystal on the third harmonic generation (THG) efficiency in a two crystal frequency tripling scheme. By detuning the temperature of the doubling crystal, the impact of a phase-mismatch in second harmonic generation (SHG) on the subsequent sum frequency mixing process was investigated. It was found that adjusting the temperature not only affected the power ratio of the second harmonic to the fundamental but also the beam diameter of the fundamental beam in the THG crystal, which was caused by self-focusing and self-defocusing of the fundamental beam, respectively. This self-action was induced by a cascaded χ(2) : χ(2) process in the phase-mismatched SHG crystal. Self-defocusing was observable for positive detuning and self-focusing for negative detuning of the phase-matching temperature. Hence, the THG efficiency was not symmetric with respect to the point of optimum phase-matching. Optimum THG was obtained for positive detuning and the resulting self-defocusing in combination with the focusing lens in front of the THG stage was also beneficial for the beam quality of the third harmonic.

Influences of powder granularity on crystallizing characteristics in mica-contained glass ceramic

NASA Astrophysics Data System (ADS)

Xu, L. N.; Kong, D. Y.; Tian, Q. B.; Lv, Z. J.

2017-09-01

A machinable mica-contained glass ceramic in the SiO2-Al2O3-MgO-F glassy system was prepared by ball milling and hot pressed sintering. Three kinds of powder sizes of base glass were chosen and the effects of the glass powder sizes on the crystallization were explored by x-ray diffraction and scanning electron microscopy techniques. The results indicate that mica crystal as a major phase and KFeSi2O6 and mullite as minor phases are crystallized. Applying pressure at 670°C has little influences on the types of crystal precipitated and the preferential growth of crystal. The powder sizes, however, have obvious effects on the morphology of precipitated mica crystals. In the glass sample with a powder size of d50=16.4 µm, the plate-shaped mica phase is precipitated. As the powder size decrease to 9.9 µm and 3.3 µm, however, the particle-shaped mica is formed instead of the plate-shaped crystals.

Crystallization kinetics of the phase change material GeSb 6Te measured with dynamic transmission electron microscopy

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

Winseck, M. M.; Cheng, H. -Y.; Campbell, G. H.

2016-03-30

GeSb 6Te is a chalcogenide-based phase change material that has shown great ptoential for use in solid-state memory devices. The crystallization kinetics of amorphous thin films of GeSb 6Te during laser crystallization were followed with dynamic transmission electron microscopy, a photo-emission electron microscopy technique with nanosecond-scale time resolution. Nine-frame movies of crystal growth were taken during laser crystallization. The nucleation rate is observed to be very low and the growth rates are very high, up to 10.8 m s –1 for amorphous as-deposited films and significantly higher for an amorphous film subject to sub-threshold laser annealing before crystallization. The measuredmore » growth rates exceed any directly measured growth rate of a phase change material. Here, the crystallization is reminiscent of explosive crystallization of elemental semiconductors both in the magnitude of the growth rate and in the resulting crystalline microstructures.« less

Polymer-stabilized liquid crystal blue phases.

PubMed

Kikuchi, Hirotsugu; Yokota, Masayuki; Hisakado, Yoshiaki; Yang, Huai; Kajiyama, Tisato

2002-09-01

Blue phases are types of liquid crystal phases that appear in a temperature range between a chiral nematic phase and an isotropic liquid phase. Because blue phases have a three-dimensional cubic structure with lattice periods of several hundred nanometres, they exhibit selective Bragg reflections in the range of visible light corresponding to the cubic lattice. From the viewpoint of applications, although blue phases are of interest for fast light modulators or tunable photonic crystals, the very narrow temperature range, usually less than a few kelvin, within which blue phases exist has always been a problem. Here we show the stabilization of blue phases over a temperature range of more than 60 K including room temperature (260-326 K). Furthermore, we demonstrate an electro-optical switching with a response time of the order of 10(-4) s for the stabilized blue phases at room temperature.

Tetragonal Lysozyme Nucleation and Crystal Growth: The Role of the Solution Phase

NASA Technical Reports Server (NTRS)

Pusey, Marc L.; Forsythe, Elizabeth; Sumida, John; Maxwell, Daniel; Gorti, Sridhar; Curreri, Peter A. (Technical Monitor)

2002-01-01

Experimental evidence indicates a dominant role of solution phase interactions in nucleating and growing tetragonal lysozyme crystals. These interactions are extensive, even at saturation, and may be a primary cause of misoriented regions in crystals grown on Earth. Microgravity, by limiting interfacial concentrations to diffusion-controlled levels, may benefit crystal quality by also reducing the extent of associated species present at the interface.

Phase transformations in 40-60-GPa shocked gneisses from the Haughton Crater (Canada): An Analytical Transmission Electron Microscopy (ATEM) study

NASA Technical Reports Server (NTRS)

Martinez, I.; Guyot, F.; Schaerer, U.

1992-01-01

In order to better understand phase transformations, chemical migration, and isotopic disequilibrium in highly shocked rocks, we have performed a microprobe and an ATEM study on gneisses shocked up to 60 GPa from the Haughton Crater. This study reveals the following chemical and structural characteristics: (1) SiO2 dominant areas are formed by a mixture of pure SiO2 polycrystalline quartz identified by electron diffraction pattern and chemical analysis and a silica-rich amorphous phase containing minor amounts of aluminium, potassium, and iron; (2) Areas with biotitelike composition are formed by less than 200-nm grains of iron-rich spinels embedded in a silica-rich amorphous phase that is very similar to the one described above; (3) Layers with feldsparlike composition are constituted by 100-200-nm-sized alumina-rich grains (the indexation of the crystalline structure is under progress) and the silica-rich amorphous phase; (4) Zones characterized by the unusual Al/Si ratio close to 1 are formed by spinel grains (200-nm-sized) embedded in the same silica-rich amorphous phase; and (5) The fracturated sillimanites contain domains with a lamellar structure, defined by the intercalation of 100-nm-wide lamellae of mullite crystals and of a silica-rich amorphous phase. These mullite crystals preserved the crystallographical orientation of the preshock sillimanite. All compositional domains, identified at the microprobe scale, can thus be explained by a mixture in different proportion between the following phases: (1) a silica-rich amorphous phase, with minor Al and K; (2) quartz crystals; (3) spinel crystals and alumina-rich crystals; (4) sillimanite; and (5) mullite. Such mixtures of amorphous phases and crystals in different proportions explain disturbed isotope systems in these rocks and chemical heterogeneities observed on the microprobe.

Special Features of the Structure of Single-Crystal Refractory Nickel Alloy Under Directed Crystallization

NASA Astrophysics Data System (ADS)

Bondarenko, Yu. A.; Echin, A. B.; Surova, V. A.; Kolodyazhnyi, M. Yu.

2017-05-01

The effect of the conditions of directed crystallization (the temperature gradient and the crystallization rate) on the dendrite spacing, on the size of the particles of the hardening γ'-phase in the arms and arm spaces of the dendrites, on the volume fraction and size of the pores, on the size of the particles of the eutectic γ/γ'-phase, and on the features of dendritic segregation in a single-crystal castable refractory alloy is studied.

Controllable light diffraction in woodpile photonic crystals filled with liquid crystal

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

Ho, Chih-Hua; Zeng, Hao; Wiersma, Diederik S.

2015-01-12

An approach to switching between different patterns of light beams transmitted through the woodpile photonic crystals filled with liquid crystals is proposed. The phase transition between the nematic and isotropic liquid crystal states leads to an observable variation of the spatial pattern transmitted through the photonic structure. The transmission profiles in the nematic phase also show polarization sensibility due to refractive index dependence on the field polarization. The experimental results are consistent with a numerical calculation by Finite Difference Time Domain method.

An unusual type of polymorphism in a liquid crystal

DOE PAGES

Li, Lin; Salamonczyk, Miroslaw; Shadpour, Sasan; ...

2018-02-19

Polymorphism is a remarkable concept in chemistry, materials science, computer science, and biology. Whether it is the ability of a material to exist in two or more crystal structures, a single interface connecting to two different entities, or alternative phenotypes of an organism, polymorphism determines function and properties. In materials science, polymorphism can be found in an impressively wide range of materials, including crystalline materials, minerals, metals, alloys, and polymers. Here in this paper we report on polymorphism in a liquid crystal. A bent-core liquid crystal with a single chiral side chain forms two structurally and morphologically significantly different liquidmore » crystal phases solely depending on the cooling rate from the isotropic liquid state. On slow cooling, the thermodynamically more stable oblique columnar phase forms, and on rapid cooling, a not heretofore reported helical microfilament phase. Since structure determines function and properties, the structural color for these phases also differs.« less

Discrete Time Crystals: Rigidity, Criticality, and Realizations.

PubMed

Yao, N Y; Potter, A C; Potirniche, I-D; Vishwanath, A

2017-01-20

Despite being forbidden in equilibrium, spontaneous breaking of time translation symmetry can occur in periodically driven, Floquet systems with discrete time-translation symmetry. The period of the resulting discrete time crystal is quantized to an integer multiple of the drive period, arising from a combination of collective synchronization and many body localization. Here, we consider a simple model for a one-dimensional discrete time crystal which explicitly reveals the rigidity of the emergent oscillations as the drive is varied. We numerically map out its phase diagram and compute the properties of the dynamical phase transition where the time crystal melts into a trivial Floquet insulator. Moreover, we demonstrate that the model can be realized with current experimental technologies and propose a blueprint based upon a one dimensional chain of trapped ions. Using experimental parameters (featuring long-range interactions), we identify the phase boundaries of the ion-time-crystal and propose a measurable signature of the symmetry breaking phase transition.

Topological Classification of Crystalline Insulators through Band Structure Combinatorics

NASA Astrophysics Data System (ADS)

Kruthoff, Jorrit; de Boer, Jan; van Wezel, Jasper; Kane, Charles L.; Slager, Robert-Jan

2017-10-01

We present a method for efficiently enumerating all allowed, topologically distinct, electronic band structures within a given crystal structure in all physically relevant dimensions. The algorithm applies to crystals without time-reversal, particle-hole, chiral, or any other anticommuting or anti-unitary symmetries. The results presented match the mathematical structure underlying the topological classification of these crystals in terms of K -theory and therefore elucidate this abstract mathematical framework from a simple combinatorial perspective. Using a straightforward counting procedure, we classify all allowed topological phases of spinless particles in crystals in class A . Employing this classification, we study transitions between topological phases within class A that are driven by band inversions at high-symmetry points in the first Brillouin zone. This enables us to list all possible types of phase transitions within a given crystal structure and to identify whether or not they give rise to intermediate Weyl semimetallic phases.

An unusual type of polymorphism in a liquid crystal

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

Li, Lin; Salamonczyk, Miroslaw; Shadpour, Sasan

Polymorphism is a remarkable concept in chemistry, materials science, computer science, and biology. Whether it is the ability of a material to exist in two or more crystal structures, a single interface connecting to two different entities, or alternative phenotypes of an organism, polymorphism determines function and properties. In materials science, polymorphism can be found in an impressively wide range of materials, including crystalline materials, minerals, metals, alloys, and polymers. Here in this paper we report on polymorphism in a liquid crystal. A bent-core liquid crystal with a single chiral side chain forms two structurally and morphologically significantly different liquidmore » crystal phases solely depending on the cooling rate from the isotropic liquid state. On slow cooling, the thermodynamically more stable oblique columnar phase forms, and on rapid cooling, a not heretofore reported helical microfilament phase. Since structure determines function and properties, the structural color for these phases also differs.« less

Crystal growth within a phase change memory cell.

PubMed

Sebastian, Abu; Le Gallo, Manuel; Krebs, Daniel

2014-07-07

In spite of the prominent role played by phase change materials in information technology, a detailed understanding of the central property of such materials, namely the phase change mechanism, is still lacking mostly because of difficulties associated with experimental measurements. Here, we measure the crystal growth velocity of a phase change material at both the nanometre length and the nanosecond timescale using phase-change memory cells. The material is studied in the technologically relevant melt-quenched phase and directly in the environment in which the phase change material is going to be used in the application. We present a consistent description of the temperature dependence of the crystal growth velocity in the glass and the super-cooled liquid up to the melting temperature.

Linear electro-optic properties of relaxor-based ferroelectric 0.24Pb(In1/2Nb1/2)O3-(0.76 − x)Pb(Mg1/3Nb2/3)O3-xPbTiO3 single crystals

PubMed Central

Wu, Fengmin; Yang, Bin; Sun, Enwei; Liu, Gang; Tian, Hao; Cao, Wenwu

2013-01-01

Linear electro-optic properties of 0.24Pb(In1/2Nb1/2)O3-(0.76 − x)Pb(Mg1/3Nb2/3)O3-xPbTiO3 single crystals, with compositions in the rhombohedral, morphotropic phase boundary (MPB) and tetragonal phases, have been investigated. Very large effective electro-optic coefficient γc (204 pm/V) was observed in a crystal with the MPB composition when it is poled along [001]. The rhombohedral phase (x = 0.27 and 0.30) single crystals poled along [111] direction and tetragonal phase (x = 0.39) single crystal poled along [001] direction are in single domain, and their electro-optic coefficients (γc = 76, 94, and 43 pm/V for the crystals with x = 0.27, 0.30, and 0.39, respectively) were found to be much higher than that of traditional electro-optic single crystal LiNbO3 (γc = 19.9 pm/V). The electro-optic coefficients of the single crystal in the rhombohedral phase have excellent temperature stability in the experimental temperature range of 10–40 °C. The half-wave voltage Vπ was calculated to be much lower (less than 1000 V) than that of LiNbO3 single crystal (2800 V). These superior properties make the ternary relaxor-PT single crystals very promising for electro-optic modulation applications. PMID:23922449

Antisolvent membrane crystallization of pharmaceutical compounds.

PubMed

Di Profio, Gianluca; Stabile, Carmen; Caridi, Antonella; Curcio, Efrem; Drioli, Enrico

2009-12-01

This article describes a modification of the conventional membrane crystallization technique in which a membrane is used to dose the solvent/antisolvent composition to generate supersaturation and induce crystallization in a drug solution. Two operative configurations are proposed: (a) solvent/antisolvent demixing crystallization, where the solvent is removed in at higher flow rate than the antisolvent so that phase inversion promotes supersaturation and (b) antisolvent addition, in which the antisolvent is dosed into the crystallizing drug solution. In both cases, solvent/antisolvent migration occurs in vapor phase and it is controlled by the porous membrane structure, acting on the operative process parameters. This mechanism is different than that observed when forcing the liquid phases through the pores and the more finely controllable supersaturated environment would generate crystals with the desired characteristics. Two organic molecules of relevant industrial implication, like paracetamol and glycine, were used to test the new systems. Experiments demonstrated that, by using antisolvent membrane crystallization in both configurations, accurate control of solution composition at the crystallization point has been achieved with effects on crystals morphology. 2009 Wiley-Liss, Inc. and the American Pharmacists Association

What’s in a drop? Correlating observations and outcomes to guide macromolecular crystallization experiments

PubMed Central

Luft, Joseph R.; Wolfley, Jennifer R.; Snell, Edward H.

2011-01-01

Observations of crystallization experiments are classified as specific outcomes and integrated through a phase diagram to visualize solubility and thereby direct subsequent experiments. Specific examples are taken from our high-throughput crystallization laboratory which provided a broad scope of data from 20 million crystallization experiments on 12,500 different biological macromolecules. The methods and rationale are broadly and generally applicable in any crystallization laboratory. Through a combination of incomplete factorial sampling of crystallization cocktails, standard outcome classifications, visualization of outcomes as they relate chemically and application of a simple phase diagram approach we demonstrate how to logically design subsequent crystallization experiments. PMID:21643490

Investigation of phase transitions in LiK 1- x(NH 4) xSO 4 mixed crystal

NASA Astrophysics Data System (ADS)

Freire, P. T. C.; Paraguassu, W.; Silva, A. P.; Pilla, O.; Teixeira, A. M. R.; Sasaki, J. M.; Mendes Filho, J.; Guedes, I.; Melo, F. E. A.

1999-02-01

We present Raman scattering results on LiK 1- x(NH 4) xSO 4 mixed crystal for temperatures between 100 and 300 K. We observed that in this temperature range the crystal undergoes two different phase transitions, which we call Bansal and Tomaszewski phase transitions. The introduction of ammonium ions in the potassium sites increases the C 66→C 3v4 (Bansal) phase transition temperature and decreases the Tomaszewski phase transition temperature. Finally, the most impressive effect of the presence of ammonium impurity in the LiKSO 4 structure is the decrease in the temperature hysteresis of Bansal phase transition and the almost complete destruction of hysteresis in the Tomaszewski phase transition, leading to a high temperature range of stability of the trigonal phase.

Phase behavior of thermotropic chiral liquid crystal with wide blue phase

NASA Astrophysics Data System (ADS)

Jessy, P. J.; Radha, S.; Nainesh, Patel

2018-04-01

We modified the phase transitions of a thermotropic chiral nematic liquid crystal system with various concentrations of chiral component and investigated their phase behavior and optical properties. The study shows that coupling between chirality and nematicity of liquid crystals lead to changes in phase morphology with extended temperature window of blue phase including human body temperatures and enhanced thermochromism performance. The temperature dependent refractive index analysis in the visible spectral region reveals that the optical modulation due to pitch variation of helical pattern results in the creation of new mesophases and more pronounced chirality in mixtures leading to blue phase which can be controlled by the chiral concentration. The appearance of extended blue phases with primary colors will pave way for the development of new photonic devices.

Defense waste processing facility (DWPF) liquids model: revisions for processing higher TIO 2 containing glasses

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

Jantzen, C. M.; Edwards, T. B.; Trivelpiece, C. L.

Radioactive high level waste (HLW) at the Savannah River Site (SRS) has successfully been vitrified into borosilicate glass in the Defense Waste Processing Facility (DWPF) since 1996. Vitrification requires stringent product/process (P/P) constraints since the glass cannot be reworked once it is poured into ten foot tall by two foot diameter canisters. A unique “feed forward” statistical process control (SPC) was developed for this control rather than statistical quality control (SQC). In SPC, the feed composition to the DWPF melter is controlled prior to vitrification. In SQC, the glass product would be sampled after it is vitrified. Individual glass property-compositionmore » models form the basis for the “feed forward” SPC. The models transform constraints on the melt and glass properties into constraints on the feed composition going to the melter in order to guarantee, at the 95% confidence level, that the feed will be processable and that the durability of the resulting waste form will be acceptable to a geologic repository. This report documents the development of revised TiO 2, Na 2O, Li 2O and Fe 2O 3 coefficients in the SWPF liquidus model and revised coefficients (a, b, c, and d).« less

Sun position calculator (SPC) for Landsat imagery with geodetic latitudes

NASA Astrophysics Data System (ADS)

Seong, Jeong C.

2015-12-01

Landsat imagery comes with sun position information such as azimuth and sun elevation, but they are available only at the center of a scene. To aid in the use of Landsat imagery for various solar radiation applications such as topographic correction, solar power, urban heat island, agriculture, climate and vegetation, it is necessary to calculate the sun position information at every pixel. This research developed a PC application that creates sun position data layers in ArcGIS at every pixel in a Landsat scene. The SPC program is composed of two major routines - converting universal transverse Mercator (UTM) projection coordinates to geographic longitudes and latitudes, and calculating sun position information based on the Meeus' routine. For the latter, an innovative method was also implemented to account for the Earth's flattening on an ellipsoid. The Meeus routine implemented in this research showed about 0.2‧ of mean absolute difference from the National Renewable Energy Laboratory (NREL) Solar Position Algorithm (SPA) routine when solar zenith and azimuth angles were tested with every 30 min data at four city locations (Fairbanks, Atlanta, Sydney and Rio Grande) on June 30, 2014. The Meeus routine was about ten times faster than the SPA routine. Professionals who need the Sun's position information for Landsat imagery will benefit from the SPC application.

Results of using the global positioning system to maintain the time and frequency synchronization in the Deep Space Network

NASA Technical Reports Server (NTRS)

Clements, P. A.; Kirk, A.; Unglaub, R.

1987-01-01

There are two hydrogen maser clocks located at each signal processing center (SPC) in the DSN. Close coordination of the time and frequency of the SPC clocks is needed to navigate spacecraft to the outer planets. A recent example was the Voyager spacecraft's encounter with Uranus in January 1986. The clocks were adjusted with the goal of minimizing time and frequency offsets between the SPCs at encounter. How time and frequency at each SPC is estimated using data acquired from the Global Positioning System Timing Receivers operating on the NBS-BIH (National Bureau of Standards-Bureau International de l'Heure) tracking schedule is described. These data are combined with other available timing receiver data to calculate the time offset estimates. The adjustment of the clocks is described. It was determined that long range hydrogen maser drift is quite predictable and adjustable within limits. This enables one to minimize time and frequency differences between the three SPCs for many months by matching the drift rates of the three standards. Data acquisition and processing techniques using a Kalman filter to make estimates of time and frequency offsets between the clocks at the SPCs and UTC(NBS) (Coordinated Universal Time realized at NBS) are described.

Statistical process control charts for attribute data involving very large sample sizes: a review of problems and solutions.

PubMed

Mohammed, Mohammed A; Panesar, Jagdeep S; Laney, David B; Wilson, Richard

2013-04-01

The use of statistical process control (SPC) charts in healthcare is increasing. The primary purpose of SPC is to distinguish between common-cause variation which is attributable to the underlying process, and special-cause variation which is extrinsic to the underlying process. This is important because improvement under common-cause variation requires action on the process, whereas special-cause variation merits an investigation to first find the cause. Nonetheless, when dealing with attribute or count data (eg, number of emergency admissions) involving very large sample sizes, traditional SPC charts often produce tight control limits with most of the data points appearing outside the control limits. This can give a false impression of common and special-cause variation, and potentially misguide the user into taking the wrong actions. Given the growing availability of large datasets from routinely collected databases in healthcare, there is a need to present a review of this problem (which arises because traditional attribute charts only consider within-subgroup variation) and its solutions (which consider within and between-subgroup variation), which involve the use of the well-established measurements chart and the more recently developed attribute charts based on Laney's innovative approach. We close by making some suggestions for practice.

Statistical monitoring of the hand, foot and mouth disease in China.

PubMed

Zhang, Jingnan; Kang, Yicheng; Yang, Yang; Qiu, Peihua

2015-09-01

In a period starting around 2007, the Hand, Foot, and Mouth Disease (HFMD) became wide-spreading in China, and the Chinese public health was seriously threatened. To prevent the outbreak of infectious diseases like HFMD, effective disease surveillance systems would be especially helpful to give signals of disease outbreaks as early as possible. Statistical process control (SPC) charts provide a major statistical tool in industrial quality control for detecting product defectives in a timely manner. In recent years, SPC charts have been used for disease surveillance. However, disease surveillance data often have much more complicated structures, compared to the data collected from industrial production lines. Major challenges, including lack of in-control data, complex seasonal effects, and spatio-temporal correlations, make the surveillance data difficult to handle. In this article, we propose a three-step procedure for analyzing disease surveillance data, and our procedure is demonstrated using the HFMD data collected during 2008-2009 in China. Our method uses nonparametric longitudinal data and time series analysis methods to eliminate the possible impact of seasonality and temporal correlation before the disease incidence data are sequentially monitored by a SPC chart. At both national and provincial levels, our proposed method can effectively detect the increasing trend of disease incidence rate before the disease becomes wide-spreading. © 2015, The International Biometric Society.

CONTROL CHART DASHBOARDS MANAGING YOUR NUMBERS INSTEAD OF YOU NUMBER MANAGING YOU

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

PREVETTE, S.S.

2006-11-15

This paper, which documents Fluor Hanford's application of Statistical Process Control (SPC) and Dashboards to support planning and decision making, is a sequel to ''Leading with Leading Indicators'' that was presented at WM 05. This year's paper provides more detail on management's use of SPC and control charts and discusses their integration into an executive summary using the popular color-cod3ed dashboard methodology. Fluor Hanford has applied SPC in a non-traditional (that is non-manufacturing) manner. Dr. Shewhart's 75-year-old control-chart methodologies have been updated to modern data processing, but are still founded on his sound, tried and true principles. These methods aremore » playing a key role in safety and quality at what has been called the world's largest environmental cleanup project. The US Department of Energy's (DOE's) Hanford Site played a pivotal role in the nation's defense, beginning in the 1940s when it was established as part of the Manhattan Project. After more than 50 years of producing nuclear weapons, Hanford--which covers 586 square miles in southeastern Washington state--is now focused on three outcomes: (1) restoring the Columbia River corridor for multiple uses; (2) transitioning the central plateau to support long-term waste management; and (3) putting DOE assets to work for the future.« less

Impact of Ultrasound on Short Peripheral Intravenous Catheter Placement on Vein Thrombosis Risk.

PubMed

Holder, Max R; Stutzman, Sonja E; Olson, DaiWai M

Approximately 90% of hospitalized patients have a short peripheral intravenous catheter (SPC) placed. Methods of inserting the catheter have evolved over time and now include the use of ultrasound (US)-guided procedures for placement. Little is known about the impact that US-guided procedures have on the vein. This study compared the rate of venous thrombosis in patients with and without US-guided catheter placement. This prospective, single-blind, observational study assessed for venous thrombosis in 153 veins from 135 patients. Veins were evaluated by a research nurse blinded to the method of placement between 48 and 72 hours after the SPC was placed. The Fisher exact test showed a significant difference between vessel compressibility and catheter insertion method (P = .0012). The proportion of noncompressible veins was significantly greater when US was used in comparison with freehand SPC insertion. The Mantel-Haenszel chi-square value of 10.34 (P = .0013) showed that US insertion technique is associated with a higher likelihood of noncompressible veins. This pilot study provides compelling evidence that the use of US to assist with catheter placement is associated with a higher rate of noncompressible veins at day 2 or 3. Further studies are needed with a larger sample to determine the generalizability of the results from this pilot study.

Intrinsic crystal phase separation in the antiferromagnetic superconductor Rb(y)Fe(2-x)Se2: a diffraction study.

PubMed

Yu Pomjakushin, V; Krzton-Maziopa, A; Pomjakushina, E V; Conder, K; Chernyshov, D; Svitlyk, V; Bosak, A

2012-10-31

The crystal and magnetic structures of the superconducting iron-based chalcogenides Rb(y)Fe(2-x)Se(2) have been studied by means of single-crystal synchrotron x-ray and high-resolution neutron powder diffraction in the temperature range 2-570 K. The ground state of the crystal is an intrinsically phase-separated state with two distinct-by-symmetry phases. The main phase has the iron vacancy ordered √5 × √5 superstructure (I4/m space group) with AFM ordered Fe spins. The minority phase does not have √5 × √5-type of ordering and has a smaller in-plane lattice constant a and larger tetragonal c-axis and can be well described by assuming the parent average vacancy disordered structure (I4/mmm space group) with the refined stoichiometry Rb(0.60(5))(Fe(1.10(5))Se)(2). The minority phase amounts to 8-10% mass fraction. The unit cell volume of the minority phase is 3.2% smaller than the one of the main phase at T = 2 K and has quite different temperature dependence. The minority phase merges with the main vacancy ordered phase on heating above the phase separation temperature T(P) = 475 K. The spatial dimensions of the phase domains strongly increase above T(P) from 1000 to >2500 Å due to the integration of the regions of the main phase that were separated by the second phase at low temperatures. Additional annealing of the crystals at a temperature T = 488 K, close to T(P), for a long time drastically reduces the amount of the minority phase.

75 FR 49865 - Extension of Comment Period; Airplane and Engine Certification Requirements in Supercooled Large...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-16

... Ice Crystal Icing Conditions AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of... airplanes most affected by these icing conditions, mixed phase and ice crystal conditions for all transport category airplanes, and supercooled large drop, mixed phase, and ice crystal icing conditions for all...

Polarizability of acetanilide and RDX in the crystal: effect of molecular geometry

NASA Astrophysics Data System (ADS)

Tsiaousis, D.; Munn, R. W.; Smith, P. J.; Popelier, P. L. A.

2004-10-01

Density-functional theory with the B3LYP functional at the 6-311++G** level is used to calculate the dipole moment and the static polarizability for acetanilide and 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX) in their in-crystal structures. For acetanilide the dipole moment is 2{1}/{2}% larger than for the gas-phase structure and for RDX (where there is a gross geometry change) it is 15% larger. The polarizability for the in-crystal structure is smaller than for the gas-phase structure by 3% for both species, whereas the in-crystal effective optical polarizability is larger than the gas-phase static polarizability for both crystals. Hence, effects in addition to the molecular geometry change in the crystal must be considered in order to interpret the effective polarizability completely.

Determination of the rate of crystal growth from the gas phase under conditions of turbulent free convection

NASA Astrophysics Data System (ADS)

Alad'Ev, S. I.

1987-04-01

Crystal growth in vertical and horizontal cylindrical vials, with the substrate and the source serving as the vial ends, is investigated analytically, assuming that the medium consists of a binary mixture of an active and an inert gas. The active gas is made up of the gaseous products of reactions taking place at the substrate and at the source. It is shown that turbulent free convection leads to an increase in crystal growth rate. All other conditions being equal, crystal growth in vertical vials is greater than that in horizontal ones; in both cases crystal growth rate increases with the vial radius, temperature gradient in the gas phase, and gas phase density. The results are compared with experimental data on the growth of Ge crystals in the Ge-GeI4 system.

Broadband one-dimensional photonic crystal wave plate containing single-negative materials.

PubMed

Chen, Yihang

2010-09-13

The properties of the phase shift of wave reflected from one-dimensional photonic crystals consisting of periodic layers of single-negative (permittivity- or permeability-negative) materials are demonstrated. As the incident angle increases, the reflection phase shift of TE wave decreases, while that of TM wave increases. The phase shifts of both polarized waves vary smoothly as the frequency changes across the photonic crystal stop band. Consequently, the difference between the phase shift of TE and that of TM wave could remain constant in a rather wide frequency range inside the stop band. These properties are useful to design wave plate or retarder which can be used in wide spectral band. In addition, a broadband photonic crystal quarter-wave plate is proposed.

Morphology and kinetics of crystals growth in amorphous films of Cr2O3, deposited by laser ablation

NASA Astrophysics Data System (ADS)

Bagmut, Aleksandr

2018-06-01

An electron microscopic investigation was performed on the structure and kinetics of the crystallization of amorphous Cr2O3 films, deposited by pulsed laser sputtering of chromium target in an oxygen atmosphere. The crystallization was initiated by the action of an electron beam on an amorphous film in the column of a transmission electron microscope. The kinetic curves were plotted on the basis of a frame-by-frame analysis of the video recorded during the crystallization of the film. It was found that the amorphous phase - crystal phase transition in Cr2O3 films occurs as a layer polymorphic crystallization and is characterized by the values of the dimensionless relative length unit δ0 ≈ 2000-3100. The action of the electron beam initiates the formation of crystals of two basic morphological forms: disk-shaped and sickle-shaped. Growth of a disk-shaped crystals is characterized by a constant rate v and the quadratic dependence of the fraction of the crystalline phase x on the time t. Sickle-shaped crystal at an initial stage, as it grows, becomes as ring-shaped and disk-shaped crystal. The growth of a sickle-shaped crystal is characterized by normal and tangential velocity components, which depend on the time as ∼√t and as ∼1/√t respectively The end point of the arc at the interface between the amorphous and crystalline phases as the crystal grows describes a curve, which is similar to the Fermat helix. For sickle-shaped, as well as for disk-shaped crystals, the degree of crystallinity x ∼ t2.

Strategies for the crystallization of viruses: using phase diagrams and gels to produce 3D crystals of Grapevine fanleaf virus.

PubMed

Schellenberger, Pascale; Demangeat, Gérard; Lemaire, Olivier; Ritzenthaler, Christophe; Bergdoll, Marc; Oliéric, Vincent; Sauter, Claude; Lorber, Bernard

2011-05-01

The small icosahedral plant RNA nepovirus Grapevine fanleaf virus (GFLV) is specifically transmitted by a nematode and causes major damage to vineyards worldwide. To elucidate the molecular mechanisms underlying the recognition between the surface of its protein capsid and cellular components of its vector, host and viral proteins synthesized upon infection, the wild type GFLV strain F13 and a natural mutant (GFLV-TD) carrying a Gly₂₉₇Asp mutation were purified, characterized and crystallized. Subsequently, the geometry and volume of their crystals was optimized by establishing phase diagrams. GFLV-TD was twice as soluble as the parent virus in the crystallization solution and its crystals diffracted X-rays to a resolution of 2.7 Å. The diffraction limit of GFLV-F13 crystals was extended from 5.5 to 3 Å by growth in agarose gel. Preliminary crystallographic analyses indicate that both types of crystals are suitable for structure determination. Keys for the successful production of GFLV crystals include the rigorous quality control of virus preparations, crystal quality improvement using phase diagrams, and crystal lattice reinforcement by growth in agarose gel. These strategies are applicable to the production of well-diffracting crystals of other viruses and macromolecular assemblies. Copyright © 2011 Elsevier Inc. All rights reserved.

Anxiety, depression and self-esteem in children with well-controlled asthma: case-control study.

PubMed

Letitre, Sarah L; de Groot, Eric P; Draaisma, Eelco; Brand, Paul L P

2014-08-01

Although asthma has been linked to psychological morbidity, this relationship may be confounded by poor asthma control. We aimed to compare the prevalence of anxiety, depression and low level of self-esteem in children with well-controlled asthma with that of healthy peers. Dedicated asthma clinic in a general hospital. 70 patients with mostly well-controlled asthma and 70 matched healthy controls. Comprehensive asthma education, management and follow-up for asthma patients. Validated Dutch versions of the Childhood Depression inventory (CDI), Revised Fear Survey for Children (RFSC), Self Perception Profile for Children (SPC-C) and Adolescents (SPC-A) and State-Trait Anxiety Inventory for Children (STAIC). Asthma control assessed by asthma control questionnaire. No significant differences were found in total scores between asthmatics and controls (95% CI for difference -0.2 to 2.9 for CDI, -5.9 to 11.2 for RFSC, -19.9 to 6.3 for SPC-C, -24.1 to 5.0 for SPC-A and -2.7 to 0.01 for STAIC). There were also no significant differences between asthmatics and controls in the prevalence of scores exceeding cut-off levels for clinically relevant anxiety (13.3 vs 13.0%, p=0.605), depression (12.9 vs 5.7%, p=0.243) or low self-esteem (21.4 vs 12.9%, p=0.175). A significant correlation was found between poorer asthma control and CDI (p=0.012) and anxiety trait symptoms (p<0.001). Children with well-controlled asthma enrolled in a comprehensive asthma management programme do not have an increased risk of anxiety, depression and poor self-esteem. Earlier reports of psychological comorbidity in asthma may have been related to inadequately controlled asthma. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

TU-FG-201-09: Predicting Accelerator Dysfunction

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

Able, C; Nguyen, C; Baydush, A

Purpose: To develop an integrated statistical process control (SPC) framework using digital performance and component data accumulated within the accelerator system that can detect dysfunction prior to unscheduled downtime. Methods: Seven digital accelerators were monitored for twelve to 18 months. The accelerators were operated in a ‘run to failure mode’ with the individual institutions determining when service would be initiated. Institutions were required to submit detailed service reports. Trajectory and text log files resulting from a robust daily VMAT QA delivery were decoded and evaluated using Individual and Moving Range (I/MR) control charts. The SPC evaluation was presented in amore » customized dashboard interface that allows the user to review 525 monitored parameters (480 MLC parameters). Chart limits were calculated using a hybrid technique that includes the standard SPC 3σ limits and an empirical factor based on the parameter/system specification. The individual (I) grand mean values and control limit ranges of the I/MR charts of all accelerators were compared using statistical (ranked analysis of variance (ANOVA)) and graphical analyses to determine consistency of operating parameters. Results: When an alarm or warning was directly connected to field service, process control charts predicted dysfunction consistently on beam generation related parameters (BGP)– RF Driver Voltage, Gun Grid Voltage, and Forward Power (W); beam uniformity parameters – angle and position steering coil currents; and Gantry position accuracy parameter: cross correlation max-value. Control charts for individual MLC – cross correlation max-value/position detected 50% to 60% of MLCs serviced prior to dysfunction or failure. In general, non-random changes were detected 5 to 80 days prior to a service intervention. The ANOVA comparison of BGP determined that each accelerator parameter operated at a distinct value. Conclusion: The SPC framework shows promise. Long term monitoring coordinated with service will be required to definitively determine the effectiveness of the model. Varian Medical System, Inc. provided funding in support of the research presented.« less

Blood phenylalanine concentrations in patients with PAH-deficient hyperphenylalaninaemia off diet without and with three different single oral doses of tetrahydrobiopterin: assessing responsiveness in a model of statistical process control.

PubMed

Lindner, M; Gramer, G; Garbade, S F; Burgard, P

2009-08-01

Tetrahydrobiopterin (BH(4)) cofactor loading is a standard procedure to differentiate defects of BH(4) metabolism from phenylalanine hydroxylase (PAH) deficiency. BH(4) responsiveness also exists in PAH-deficient patients with high residual PAH activity. Unexpectedly, single cases with presumed nil residual PAH activity have been reported to be BH(4) responsive, too. BH(4) responsiveness has been defined either by a >or=30% reduction of blood Phe concentration after a single BH(4) dose or by a decline greater than the individual circadian Phe level variation. Since both methods have methodological disadvantages, we present a model of statistical process control (SPC) to assess BH(4) responsiveness. Phe levels in 17 adult PKU patients of three phenotypic groups off diet were compared without and with three different single oral dosages of BH(4) applied in a double-blind randomized cross-over design. Results are compared for >or=30% reduction and SPC. The effect of BH(4) by >or=30% reduction was significant for groups (p < 0.01) but not for dose (p = 0.064), with no interaction of group with dose (p = 0.24). SPC revealed significant effects for group (p < 0.01) and the interaction for group with dose (p < 0.05) but not for dose alone (p = 0.87). After one or more loadings, seven patients would be judged to be BH(4) responsive either by the 30% criterion or by the SPC model, but only three by both. Results for patients with identical PAH genotype were not very consistent within (for different BH(4) doses) and between the two models. We conclude that a comparison of protein loadings without and with BH(4) combined with a standardized procedure for data analysis and decision would increase the reliability of diagnostic results.

Building information for systematic improvement of the prevention of hospital-acquired pressure ulcers with statistical process control charts and regression.

PubMed

Padula, William V; Mishra, Manish K; Weaver, Christopher D; Yilmaz, Taygan; Splaine, Mark E

2012-06-01

To demonstrate complementary results of regression and statistical process control (SPC) chart analyses for hospital-acquired pressure ulcers (HAPUs), and identify possible links between changes and opportunities for improvement between hospital microsystems and macrosystems. Ordinary least squares and panel data regression of retrospective hospital billing data, and SPC charts of prospective patient records for a US tertiary-care facility (2004-2007). A prospective cohort of hospital inpatients at risk for HAPUs was the study population. There were 337 HAPU incidences hospital wide among 43 844 inpatients. A probit regression model predicted the correlation of age, gender and length of stay on HAPU incidence (pseudo R(2)=0.096). Panel data analysis determined that for each additional day in the hospital, there was a 0.28% increase in the likelihood of HAPU incidence. A p-chart of HAPU incidence showed a mean incidence rate of 1.17% remaining in statistical control. A t-chart showed the average time between events for the last 25 HAPUs was 13.25 days. There was one 57-day period between two incidences during the observation period. A p-chart addressing Braden scale assessments showed that 40.5% of all patients were risk stratified for HAPUs upon admission. SPC charts complement standard regression analysis. SPC amplifies patient outcomes at the microsystem level and is useful for guiding quality improvement. Macrosystems should monitor effective quality improvement initiatives in microsystems and aid the spread of successful initiatives to other microsystems, followed by system-wide analysis with regression. Although HAPU incidence in this study is below the national mean, there is still room to improve HAPU incidence in this hospital setting since 0% incidence is theoretically achievable. Further assessment of pressure ulcer incidence could illustrate improvement in the quality of care and prevent HAPUs.

The energetics of adhesion in composite materials

NASA Astrophysics Data System (ADS)

Harding, Philip Hiram

Composite materials are used throughout modern society, and often the most important parameter in determining their properties is the adhesion at material interfaces within the composite. A broad investigation is completed, the global objective of which is to develop understanding of the role of adhesion in composite materials. The scope of this study ranges from macroscopic effects of adhesion on filled polymer composites to microscopic adhesion measurements with engineered interfaces. The surface of a filler material is systematically modified and surface characterization techniques are used to quantify the influence of the surface treatments on surface energetics and wetting properties. Filled polymer composites are prepared and composite mechanical properties determined with beam deflection tests. Filler surface treatments significantly alter the composite yield stress for composites which fail interfacially and are observed to increase or decrease mechanical strength, depending on the chemical nature of the modification. Thermodynamic adhesion mechanisms active at the filler-matrix interfaces are then explored by making direct interfacial strength measurements whereby a single spherical particle is introduced into the polymeric matrix. Interfacial strength is determined by submitting the single-particle composite (SPC) to uni-axial tension and relating the macroscopic stress at interfacial failure to that experienced at the interface. The technique provides a measurement of interfacial strength between two elastic materials, one unaffected by frictional forces, viscoelasticity, and thermal stresses. The SPC measurements are used to verify proposed adhesion mechanisms at the various filler-polymer interfaces and establish the role of adhesion in the filled polymer composites. The SPC technique is then used to investigate the adhesion promotion mechanism of organofunctional silanes, which are shown to be controlled by the compatibility and penetration of the silane organofunctional group. The effects of thermal residual stresses on interfacial strength are also investigated using the SPC technique. Processing conditions, i.e., time-temperature profiles, are used to systematically vary the thermal residual stresses within the polymeric matrix. The interfaces studied are deleteriously affected by increases in thermal residual stresses.

Two Enzymes of a Complete Degradation Pathway for Linear Alkylbenzenesulfonate (LAS) Surfactants: 4-Sulfoacetophenone Baeyer-Villiger Monooxygenase and 4-Sulfophenylacetate Esterase in Comamonas testosteroni KF-1

PubMed Central

Weiss, Michael; Denger, Karin; Huhn, Thomas

2012-01-01

Complete biodegradation of the surfactant linear alkylbenzenesulfonate (LAS) is accomplished by complex bacterial communities in two steps. First, all LAS congeners are degraded into about 50 sulfophenylcarboxylates (SPC), one of which is 3-(4-sulfophenyl)butyrate (3-C4-SPC). Second, these SPCs are mineralized. 3-C4-SPC is mineralized by Comamonas testosteroni KF-1 in a process involving 4-sulfoacetophenone (SAP) as a metabolite and an unknown inducible Baeyer-Villiger monooxygenase (BVMO) to yield 4-sulfophenyl acetate (SPAc) from SAP (SAPMO enzyme); hydrolysis of SPAc to 4-sulfophenol and acetate is catalyzed by an unknown inducible esterase (SPAc esterase). Transcriptional analysis showed that one of four candidate genes for BVMOs in the genome of strain KF-1, as well as an SPAc esterase candidate gene directly upstream, was inducibly transcribed during growth with 3-C4-SPC. The same genes were identified by enzyme purification and peptide fingerprinting-mass spectrometry when SAPMO was enriched and SPAc esterase purified to homogeneity by protein chromatography. Heterologously overproduced pure SAPMO converted SAP to SPAc and was active with phenylacetone and 4-hydroxyacetophenone but not with cyclohexanone and progesterone. SAPMO showed the highest sequence homology to the archetypal phenylacetone BVMO (57%), followed by steroid BVMO (55%) and 4-hydroxyacetophenone BVMO (30%). Finally, the two pure enzymes added sequentially, SAPMO with NADPH and SAP, and then SPAc esterase, catalyzed the conversion of SAP via SPAc to 4-sulfophenol and acetate in a 1:1:1:1 molar ratio. Hence, the first two enzymes of a complete LAS degradation pathway were identified, giving evidence for the recruitment of members of the very versatile type I BVMO and carboxylester hydrolase enzyme families for the utilization of a xenobiotic compound by bacteria. PMID:23001656

Designing a sun-pointing Faraday cup for solar probe plus

NASA Astrophysics Data System (ADS)

Case, A. W.; Kasper, J. C.; Daigneau, P. S.; Caldwell, D.; Freeman, M.; Gauron, T.; Maruca, B. A.; Bookbinder, J.; Korreck, K. E.; Cirtain, J. W.; Effinger, M. E.; Halekas, J. S.; Larson, D. E.; Lazarus, A. J.; Stevens, M. L.; Taylor, E. R.; Wright, K. H., Jr.

2013-06-01

The NASA Solar Probe Plus (SPP) mission will be the first spacecraft to pass through the sub-Alfvénic solar corona. The objectives of the mission are to trace the flow of energy that heats and accelerates the solar corona and solar wind, to determine the structure and dynamics of the plasma and magnetic fields at the sources of the solar wind, and to explore mechanisms that accelerate and transport energetic particles. The Solar Wind Electrons, Alphas, and Protons (SWEAP) Investigation instrument suite on SPP will measure the bulk solar wind conditions in the inner heliosphere. SWEAP consists of the Solar Probe Cup (SPC), a sun-pointing Faraday Cup, and the Solar Probe ANalyzers (SPAN), a set of 3 electrostatic analyzers that will reside in the penumbra of SPP's thermal protection system and measure solar wind ions and electrons. SPP is scheduled to launch in 2018 into an equatorial solar orbit where a sequence of Venus gravity assists will gradually lower its closest solar approach to within 9.5 solar radii (RS) of the center of the Sun. The photon flux at 9.5 RS is more than 500 times greater than at 1 AU and therefore presents a design challenge for SPC, which will point directly at the Sun. SPC is derived from the Faraday cup instruments successfully flown on spacecraft from the beginning of the space age, but updated with high temperature materials to operate through the solar encounters. Current work includes both instrument design and the development of a testing approach capable of demonstrating adequate performance in encounter conditions. This paper will briefly discuss the suite as a whole, and then focus on the design and capabilities of SPC. We will also present the planned calibration and characterization of the instrument and the testing required to demonstrate the technological readiness of the design.

Statistical quality control for volumetric modulated arc therapy (VMAT) delivery by using the machine's log data

NASA Astrophysics Data System (ADS)

Cheong, Kwang-Ho; Lee, Me-Yeon; Kang, Sei-Kwon; Yoon, Jai-Woong; Park, Soah; Hwang, Taejin; Kim, Haeyoung; Kim, Kyoung Ju; Han, Tae Jin; Bae, Hoonsik

2015-07-01

The aim of this study is to set up statistical quality control for monitoring the volumetric modulated arc therapy (VMAT) delivery error by using the machine's log data. Eclipse and a Clinac iX linac with the RapidArc system (Varian Medical Systems, Palo Alto, USA) are used for delivery of the VMAT plan. During the delivery of the RapidArc fields, the machine determines the delivered monitor units (MUs) and the gantry angle's position accuracy and the standard deviations of the MU ( σMU: dosimetric error) and the gantry angle ( σGA: geometric error) are displayed on the console monitor after completion of the RapidArc delivery. In the present study, first, the log data were analyzed to confirm its validity and usability; then, statistical process control (SPC) was applied to monitor the σMU and the σGA in a timely manner for all RapidArc fields: a total of 195 arc fields for 99 patients. The MU and the GA were determined twice for all fields, that is, first during the patient-specific plan QA and then again during the first treatment. The sMU and the σGA time series were quite stable irrespective of the treatment site; however, the sGA strongly depended on the gantry's rotation speed. The σGA of the RapidArc delivery for stereotactic body radiation therapy (SBRT) was smaller than that for the typical VMAT. Therefore, SPC was applied for SBRT cases and general cases respectively. Moreover, the accuracy of the potential meter of the gantry rotation is important because the σGA can change dramatically due to its condition. By applying SPC to the σMU and σGA, we could monitor the delivery error efficiently. However, the upper and the lower limits of SPC need to be determined carefully with full knowledge of the machine and log data.

Evaluation of Normalization Methods on GeLC-MS/MS Label-Free Spectral Counting Data to Correct for Variation during Proteomic Workflows

NASA Astrophysics Data System (ADS)

Gokce, Emine; Shuford, Christopher M.; Franck, William L.; Dean, Ralph A.; Muddiman, David C.

2011-12-01

Normalization of spectral counts (SpCs) in label-free shotgun proteomic approaches is important to achieve reliable relative quantification. Three different SpC normalization methods, total spectral count (TSpC) normalization, normalized spectral abundance factor (NSAF) normalization, and normalization to selected proteins (NSP) were evaluated based on their ability to correct for day-to-day variation between gel-based sample preparation and chromatographic performance. Three spectral counting data sets obtained from the same biological conidia sample of the rice blast fungus Magnaporthe oryzae were analyzed by 1D gel and liquid chromatography-tandem mass spectrometry (GeLC-MS/MS). Equine myoglobin and chicken ovalbumin were spiked into the protein extracts prior to 1D-SDS- PAGE as internal protein standards for NSP. The correlation between SpCs of the same proteins across the different data sets was investigated. We report that TSpC normalization and NSAF normalization yielded almost ideal slopes of unity for normalized SpC versus average normalized SpC plots, while NSP did not afford effective corrections of the unnormalized data. Furthermore, when utilizing TSpC normalization prior to relative protein quantification, t-testing and fold-change revealed the cutoff limits for determining real biological change to be a function of the absolute number of SpCs. For instance, we observed the variance decreased as the number of SpCs increased, which resulted in a higher propensity for detecting statistically significant, yet artificial, change for highly abundant proteins. Thus, we suggest applying higher confidence level and lower fold-change cutoffs for proteins with higher SpCs, rather than using a single criterion for the entire data set. By choosing appropriate cutoff values to maintain a constant false positive rate across different protein levels (i.e., SpC levels), it is expected this will reduce the overall false negative rate, particularly for proteins with higher SpCs.

Purification and characterisation of the fission yeast Ndc80 complex.

PubMed

Matsuo, Yuzy; Maurer, Sebastian P; Surrey, Thomas; Toda, Takashi

2017-07-01

The Ndc80 complex is a conserved outer kinetochore protein complex consisting of Ndc80 (Hec1), Nuf2, Spc24 and Spc25. This complex comprises a major, if not the sole, platform with which the plus ends of the spindle microtubules directly interact. In fission yeast, several studies indicate that multiple microtubule-associated proteins including the Dis1/chTOG microtubule polymerase and the Mal3/EB1 microtubule plus-end tracking protein directly or indirectly bind Ndc80, thereby ensuring stable kinetochore-microtubule attachment. However, the purification of the Ndc80 complex from this yeast has not been achieved, which hampers the in-depth investigation as to how the outer kinetochore attaches to the plus end of the spindle microtubule. Here we report the two-step purification of the fission yeast Ndc80 holo complex from bacteria. First, we purified separately two sub-complexes consisting of Ndc80-Nuf2 and Spc24-Spc25. Then, these two sub-complexes were mixed and applied to size-exclusion chromatography. The reconstituted Ndc80 holo complex is composed of four subunits with equal stoichiometry. The complex possesses microtubule-binding activity, and Total Internal Reflection Fluorescence (TIRF)-microscopy assays show that the complex binds the microtubule lattice. Interestingly, unlike the human complex, the fission yeast complex does not track depolymerising microtubule ends. Further analysis shows that under physiological ionic conditions, the Ndc80 holo complex does not detectably bind Dis1, but instead it interacts with Mal3/EB1, by which the Ndc80 complex tracks the growing microtubule plus end. This result substantiates the notion that the Ndc80 complex plays a crucial role in establishment of the dynamic kinetochore-microtubule interface by cooperating with chTOG and EB1. Copyright © 2017 The Francis Crick Institute. Published by Elsevier Inc. All rights reserved.

Replacement of dietary soy- with air classified faba bean protein concentrate alters the hepatic transcriptome in Atlantic salmon (Salmo salar) parr.

PubMed

De Santis, Christian; Crampton, Viv O; Bicskei, Beatrix; Tocher, Douglas R

2015-12-01

The production of carnivorous fish such as Atlantic salmon (Salmo salar) is dependent on the availability of high quality proteins for feed formulations. For a number of nutritional, strategic and economic reasons, the use of plant proteins has steadily increased over the years, however a major limitation is associated with the presence of anti-nutritional factors and the nutritional profile of the protein concentrate. Investigating novel raw materials involves understanding the physiological consequences associated with the dietary inclusion of protein concentrates. The primary aim of the present study was to assess the metabolic response of salmon to increasing inclusion of air-classified faba bean protein concentrate (BPC) in feeds as a replacement for soy protein concentrate (SPC). Specifically, we tested treatments with identical contents of fishmeal (222.4gkg(-1)) and progressively higher inclusion of BPC (0gkg(-1), 111.8gkg(-1), 223.6gkg(-1), 335.4gkg(-1), 447.2gkg(-1)) substituting SPC. This study demonstrated a dose-dependent metabolic response to a plant ingredient and was the first to compare the nutrigenomic transcriptional responses after substitution of terrestrial feed ingredients such as BPC and SPC without withdrawal of marine ingredients. It was found that after eight weeks a major physiological response in liver was only evident above 335.4gkg(-1) BPC and included decreased expression of metabolic pathways, and increased expression of genes regulating transcription and translation processes and the innate immune response. Furthermore, we showed that the nutritional stress caused by BPC resembled, at least at hepatic transcriptional level, that caused by soybean meal (included as a positive control in our experimental design). The outcomes of the present study suggested that Atlantic salmon parr might efficiently utilize moderate substitution of dietary SPC with BPC, with the optimum inclusion level being around 120gkg(-1)in the type of feeds tested here. Copyright © 2015 Elsevier Inc. All rights reserved.

Self-organized chiral colloidal crystals of Brownian square crosses.

PubMed

Zhao, Kun; Mason, Thomas G

2014-04-16

We study aqueous Brownian dispersions of microscale, hard, monodisperse platelets, shaped as achiral square crosses, in two dimensions (2D). When slowly concentrated while experiencing thermal excitations, the crosses self-organize into fluctuating 2D colloidal crystals. As the particle area fraction φA is raised, an achiral rhombic crystal phase forms at φA ≈ 0.52. Above φA ≈ 0.56, the rhombic crystal gives way to a square crystal phase that exhibits long-range chiral symmetry breaking (CSB) via a crystal-crystal phase transition; the observed chirality in a particular square crystallite has either a positive or a negative enantiomeric sense. By contrast to triangles and rhombs, which exhibit weak CSB as a result of total entropy maximization, square crosses display robust long-range CSB that is primarily dictated by how they tile space at high densities. We measure the thermal distribution of orientation angles γ of the crosses' arms relative to the diagonal bisector of the local square crystal lattice as a function of φA, and the average measured γ (φA) agrees with a re-scaled model involving efficient packing of rotated cross shapes. Our findings imply that a variety of hard achiral shapes can be designed to form equilibrium chiral phases by considering their tiling at high densities.

Method for solid state crystal growth

DOEpatents

Nolas, George S.; Beekman, Matthew K.

2013-04-09

A novel method for high quality crystal growth of intermetallic clathrates is presented. The synthesis of high quality pure phase crystals has been complicated by the simultaneous formation of both clathrate type-I and clathrate type-II structures. It was found that selective, phase pure, single-crystal growth of type-I and type-II clathrates can be achieved by maintaining sufficient partial pressure of a chemical constituent during slow, controlled deprivation of the chemical constituent from the primary reactant. The chemical constituent is slowly removed from the primary reactant by the reaction of the chemical constituent vapor with a secondary reactant, spatially separated from the primary reactant, in a closed volume under uniaxial pressure and heat to form the single phase pure crystals.

Prism-coupled Cherenkov phase-matched terahertz wave generation using a DAST crystal.

PubMed

Suizu, Koji; Shibuya, Takayuki; Uchida, Hirohisa; Kawase, Kodo

2010-02-15

Terahertz (THz) wave generation based on nonlinear frequency conversion is a promising method for realizing a tunable monochromatic high-power THz-wave source. Unfortunately, many nonlinear crystals have strong absorption in the THz frequency region. This limits efficient and widely tunable THz-wave generation. The Cherenkov phase-matching method is one of the most promising techniques for overcoming these problems. Here, we propose a prism-coupled Cherenkov phase-matching (PCC-PM) method, in which a prism with a suitable refractive index at THz frequencies is coupled to a nonlinear crystal. This has the following advantages. Many crystals can be used as THz-wave emitters; the phase-matching condition inside the crystal does not have to be observed; the absorption of the crystal does not prevent efficient generation of radiation; and pump sources with arbitrary wavelengths can be employed. Here we demonstrate PCC-PM THz-wave generation using the organic crystal 4-dimethylamino-N-metyl-4-stilbazolium tosylate (DAST) and a Si prism coupler. We obtain THz-wave radiation with tunability of approximately 0.1 to 10 THz and with no deep absorption features resulting from the absorption spectrum of the crystal. The obtained spectra did not depend on the pump wavelength in the range 1300 to 1450 nm. This simple technique shows promise for generating THz radiation using a wide variety of nonlinear crystals.

Practical physics behind growing crystals of biological macromolecules.

PubMed

Candoni, Nadine; Grossier, Romain; Hammadi, Zoubida; Morin, Roger; Veesler, Stéphane

2012-07-01

The aim of this review is to provide biocrystallographers who intend to tackle protein-crystallization with theory and practical examples. Crystallization involves two separate processes, nucleation and growth, which are rarely completely unconnected. Here we give theoretical background and concrete examples illustrating protein crystallization. We describe the nucleation of a new phase, solid or liquid, and the growth and transformation of existing crystals obtained by primary or secondary nucleation or by seeding. Above all, we believe that a thorough knowledge of the phase diagram is vital to the selection of starting position and path for any crystallization experiment.

A scanning electron microscope study of olivine crystal surfaces

NASA Technical Reports Server (NTRS)

Olsen, E. J.; Grossman, L.

1974-01-01

SEM photographs were taken of euhedral olivine grains from the Murchison C2 chondrite and several terrestrial and lunar occurrences. In general, the crystal faces of the meteorite grains are rough and uneven, with irregular growth patterns. They are very similar to crystal faces on terrestrial olivine grains that formed by sublimation from a vapor phase. They are very different from the relatively smooth and featureless surfaces of magmatic olivine crystals that precipitated from igneous melts. Qualitatively, the surface morphology of the crystal supports the contention that many euhedral crystals of olivine in C2 meteorites condensed from a gas phase.

The influence of soy oligosaccharides on apparent and true ileal amino acid digestibilities and fecal consistency in growing pigs.

PubMed

Smiricky, M R; Grieshop, C M; Albin, D M; Wubben, J E; Gabert, V M; Fahey, G C

2002-09-01

Fourteen ileally cannulated pigs (BW = 35 +/- 2 kg) were randomly allotted to a replicated 7 x 7 Latin square design experiment to evaluate the influence of the soybean oligosaccharides (OS), raffinose and stachyose, on ileal nutrient digestibility and fecal consistency. Semipurified diets containing soy protein concentrate (SPC) or soybean meal (SBM) as the sole protein sources were fed. Soy solubles (SS), a by-product of SBM processing containing 3.5% raffinose and 11.5% stachyose, were used to increase dietary raffinose and stachyose concentrations. The seven dietary treatments were SPC, SPC + 9% SS, SBM, SBM + 9% SS, SBM + 18% SS, SBM + 24,000 U alpha-galactosidase enzyme preparation/kg diet, and a low-protein casein (LPC) diet used to calculate true digestibility. Diets, with the exception of the LPC diet, were formulated to contain 17% CP. All diets contained 0.5% chromic oxide as a marker for ileal digestibility determination. The experimental periods were divided into a 5-d diet adaptation followed by 2-d of ileal digesta collection. Diets and digesta were analyzed for DM, N, Cr, amino acids (AA), raffinose, and stachyose. Fecal consistency was determined on d 6 and 7 of each experimental period. The apparent and true ileal AA digestibilities were not different (P < 0.05) for the SPC and SBM control diets. When SS was added to the SPC diet, apparent and true N and AA digestibilities were depressed (P < 0.05) with the exception of Trp and Pro. The apparent and true ileal N and AA digestibilities were not different (P > 0.05) between the SBM control and SBM + 9% SS diets with the exception of Glu. There was a linear decrease (P < 0.05) in apparent and true DM, Val, Gly, and Tyr digestibilities when increasing levels of SS were added to the SBM diet. The addition of alpha-galactosidase did not improve apparent or true ileal N or AA digestibilities except for apparent and true Val and Tyr. Ileal raffinose digestibility was improved (P < 0.05) by addition of a-galactosidase, but was not affected by any other dietary treatment. Ileal stachyose digestibility was not affected (P > 0.58) by treatment. Fecal consistency likewise was not affected (P > 0.36) by dietary treatment. In conclusion, soy OS reduced nutrient digestibilities, but the reductions were small, ranging from approximately 1.1 to 7.4 percentage units. This suggests that other factors may be negatively impacting SBM digestibility.

Crystallization and dynamical arrest of attractive hard spheres.

PubMed

Babu, Sujin; Gimel, Jean-Christophe; Nicolai, Taco

2009-02-14

Crystallization of hard spheres interacting with a square well potential was investigated by numerical simulations using so-called Brownian cluster dynamics. The phase diagram was determined over a broad range of volume fractions. The crystallization rate was studied as a function of the interaction strength expressed in terms of the second virial coefficient. For volume fractions below about 0.3 the rate was found to increase abruptly with increasing attraction at the binodal of the metastable liquid-liquid phase separation. The rate increased until a maximum was reached after which it decreased with a power law dependence on the second virial coefficient. Above a critical percolation concentration, a transient system spanning network of connected particles was formed. Crystals were formed initially as part of the network, but eventually crystallization led to the breakup of the network. The lifetime of the transient gels increased very rapidly over a small range of interaction energies. Weak attraction destabilized the so-called repulsive crystals formed in pure hard sphere systems and shifted the coexistence line to higher volume fractions. Stronger attraction led to the formation of a denser, so-called attractive, crystalline phase. Nucleation of attractive crystals in the repulsive crystalline phase was observed close to the transition.

Coexistence of twisted and untwisted crystals: An impurity/structural order model with implications for agate patterns

USGS Publications Warehouse

Comer, J.; Ortoleva, P.

2007-01-01

Coexistence of twisted and untwisted crystals is explained via a model that accounts for the coupling of the entropic and energetic effects of impurities and a supra-lattice-scale structural order parameter. It is shown that twisted impure crystals can be in equilibrium with untwisted purer ones. The model explains how coexistence can occur in agates and other systems under hydrostatic stress. The model implies that untwisted crystals grown under one set of conditions could undergo a phase separation that, when accompanied by an imposed compositional gradient, leads to commonly observed, alternating bands of twisted and untwisted crystals and, when occurring in the absence of an external gradient, mossy patterns of crystal texture can emerge. This phenomenon is not related to anisotropic applied stress. Rather coexistence is a consequence of a compositional segregation/twist phase transition. Since twist coexistence is a compositional equilibrium, it arises from the exchange between bulk phases; hence, the detailed nature of the atomic structure within an interface between twisted and untwisted zones is not relevant. The approach places crystal-twist phenomena within the theory of order/disorder phase transitions.

Forward flux sampling calculation of homogeneous nucleation rates from aqueous NaCl solutions.

PubMed

Jiang, Hao; Haji-Akbari, Amir; Debenedetti, Pablo G; Panagiotopoulos, Athanassios Z

2018-01-28

We used molecular dynamics simulations and the path sampling technique known as forward flux sampling to study homogeneous nucleation of NaCl crystals from supersaturated aqueous solutions at 298 K and 1 bar. Nucleation rates were obtained for a range of salt concentrations for the Joung-Cheatham NaCl force field combined with the Extended Simple Point Charge (SPC/E) water model. The calculated nucleation rates are significantly lower than the available experimental measurements. The estimates for the nucleation rates in this work do not rely on classical nucleation theory, but the pathways observed in the simulations suggest that the nucleation process is better described by classical nucleation theory than an alternative interpretation based on Ostwald's step rule, in contrast to some prior simulations of related models. In addition to the size of NaCl nucleus, we find that the crystallinity of a nascent cluster plays an important role in the nucleation process. Nuclei with high crystallinity were found to have higher growth probability and longer lifetimes, possibly because they are less exposed to hydration water.

Forward flux sampling calculation of homogeneous nucleation rates from aqueous NaCl solutions

NASA Astrophysics Data System (ADS)

Jiang, Hao; Haji-Akbari, Amir; Debenedetti, Pablo G.; Panagiotopoulos, Athanassios Z.

2018-01-01

We used molecular dynamics simulations and the path sampling technique known as forward flux sampling to study homogeneous nucleation of NaCl crystals from supersaturated aqueous solutions at 298 K and 1 bar. Nucleation rates were obtained for a range of salt concentrations for the Joung-Cheatham NaCl force field combined with the Extended Simple Point Charge (SPC/E) water model. The calculated nucleation rates are significantly lower than the available experimental measurements. The estimates for the nucleation rates in this work do not rely on classical nucleation theory, but the pathways observed in the simulations suggest that the nucleation process is better described by classical nucleation theory than an alternative interpretation based on Ostwald's step rule, in contrast to some prior simulations of related models. In addition to the size of NaCl nucleus, we find that the crystallinity of a nascent cluster plays an important role in the nucleation process. Nuclei with high crystallinity were found to have higher growth probability and longer lifetimes, possibly because they are less exposed to hydration water.

Micropatterned photoalignment for wavefront controlled switchable optical devices

NASA Astrophysics Data System (ADS)

Glazar, Nikolaus

Photoalignment is a well-established technique for surface alignment of the liquid crystal director. Previously, chrome masks were necessary for patterned photoalignment but were difficult to use, costly, and inflexible. To extend the capabilities of photoalignment we built an automated maskless multi-domain photoalignment device based on a DMD (digital multimirror device) projection system. The device is capable of creating arbitrary photoalignment patterns with micron-sized features. Pancharatnam-Berry phase (PB-phase) is a geometric phase that arises from cyclic change of polarization state. By varying the azimuthal anchoring angle in a hybrid-aligned liquid crystal cell we can control the spatial variation of the PB-phase shift. Using our automated photoalignment device to align the liquid crystal arbitrary wave front manipulations are possible. The PB-phase shift effect is maximized when the cell is tuned to have a half-wave retardation and disappears at full-wave retardation, so the cell can be switched on and off by applying a voltage. Two wavefront controlled devices developed using this technique will be discussed: A switchable liquid crystal phase shift mask for creating sub-diffraction sized photolithographic features, and a transparent diffractive display that utilizes a switchable liquid crystal diffraction grating.

Characterization of submillisecond response optical addressing phase modulator based on low light scattering polymer network liquid crystal

NASA Astrophysics Data System (ADS)

Xiangjie, Zhao; Cangli, Liu; Jiazhu, Duan; Dayong, Zhang; Yongquan, Luo

2015-01-01

Optically addressed conventional nematic liquid crystal spatial light modulator has attracted wide research interests. But the slow response speed limited its further application. In this paper, polymer network liquid crystal (PNLC) was proposed to replace the conventional nematic liquid crystal to enhance the response time to the order of submillisecond. The maximum light scattering of the employed PNLC was suppressed to be less than 2% at 1.064 μm by optimizing polymerization conditions and selecting large viscosity liquid crystal as solvent. The occurrence of phase ripple phenomenon due to electron diffusion and drift in photoconductor was found to deteriorate the phase modulation effect of the optical addressed PNLC phase modulator. The wavelength effect and AC voltage frequency effect on the on state dynamic response of phase change was investigated by experimental methods. These effects were interpreted by electron diffusion and drift theory based on the assumption that free electron was inhomogeneously distributed in accordance with the writing beam intensity distribution along the incident direction. The experimental results indicated that the phase ripple could be suppressed by optimizing the wavelength of the writing beam and the driving AC voltage frequency when varying the writing beam intensity to generate phase change in 2π range. The modulation transfer function was also measured.

Phase field modeling of rapid crystallization in the phase-change material AIST

NASA Astrophysics Data System (ADS)

Tabatabaei, Fatemeh; Boussinot, Guillaume; Spatschek, Robert; Brener, Efim A.; Apel, Markus

2017-07-01

We carry out phase field modeling as a continuum simulation technique in order to study rapid crystallization processes in the phase-change material AIST (Ag4In3Sb67Te26). In particular, we simulate the spatio-temporal evolution of the crystallization of a molten area of the phase-change material embedded in a layer stack. The simulation model is adapted to the experimental conditions used for recent measurements of crystallization rates by a laser pulse technique. Simulations are performed for substrate temperatures close to the melting temperature of AIST down to low temperatures when an amorphous state is involved. The design of the phase field model using the thin interface limit allows us to retrieve the two limiting regimes of interface controlled (low temperatures) and thermal transport controlled (high temperatures) dynamics. Our simulations show that, generically, the crystallization velocity presents a maximum in the intermediate regime where both the interface mobility and the thermal transport, through the molten area as well as through the layer stack, are important. Simulations reveal the complex interplay of all different contributions. This suggests that the maximum switching velocity depends not only on material properties but also on the precise design of the thin film structure into which the phase-change material is embedded.

Anisotropic lattice softening near the structural phase transition in the thermosalient crystal 1,2,4,5-tetrabromobenzene.

PubMed

Zakharov, Boris A; Michalchuk, Adam A L; Morrison, Carole A; Boldyreva, Elena V

2018-03-28

The thermosalient effect (crystal jumping on heating) attracts much attention as both an intriguing academic phenomenon and in relation to its potential for the development of molecular actuators but its mechanism remains unclear. 1,2,4,5-Tetrabromobenzene (TBB) is one of the most extensively studied thermosalient compounds that has been shown previously to undergo a phase transition on heating, accompanied by crystal jumping and cracking. The difference in the crystal structures and intermolecular interaction energies of the low- and high-temperature phases is, however, too small to account for the large stress that arises over the course of the transformation. The energy is released spontaneously, and crystals jump across distances that exceed the crystal size by orders of magnitude. In the present work, the anisotropy of lattice strain is followed across the phase transition by single-crystal X-ray diffraction, focusing on the structural evolution from 273 to 343 K. A pronounced lattice softening is observed close to the transition point, with the structure becoming more rigid immediately after the phase transition. The diffraction studies are further supported by theoretical analysis of pairwise intermolecular energies and zone-centre lattice vibrations. Only three modes are found to monotonically soften up to the phase transition, with complex behaviour exhibited by the remaining lattice modes. The thermosalient effect is delayed with respect to the structural transformation itself. This can originate from the martensitic mechanism of the transformation, and the accumulation of stress associated with vibrational switching across the phase transition. The finding of this study sheds more light on the nature of the thermosalient effect in 1,2,4,5-tetrabromobenzene and can be applicable also to other thermosalient compounds.

Thermotropic liquid crystals from biomacromolecules

PubMed Central

Liu, Kai; Chen, Dong; Marcozzi, Alessio; Zheng, Lifei; Su, Juanjuan; Pesce, Diego; Zajaczkowski, Wojciech; Kolbe, Anke; Pisula, Wojciech; Müllen, Klaus; Clark, Noel A.; Herrmann, Andreas

2014-01-01

Complexation of biomacromolecules (e.g., nucleic acids, proteins, or viruses) with surfactants containing flexible alkyl tails, followed by dehydration, is shown to be a simple generic method for the production of thermotropic liquid crystals. The anhydrous smectic phases that result exhibit biomacromolecular sublayers intercalated between aliphatic hydrocarbon sublayers at or near room temperature. Both this and low transition temperatures to other phases enable the study and application of thermotropic liquid crystal phase behavior without thermal degradation of the biomolecular components. PMID:25512508

On melt solutions for the growth of CaTiO3 crystals

NASA Astrophysics Data System (ADS)

Klimm, Detlef; Schmidt, Max; Wolff, Nora; Guguschev, Christo; Ganschow, Steffen

2018-03-01

When calcium titanate crystals are grown from stoichiometric melts, they crystallize in the cubic perovskite structure. Upon cooling to room temperature they undergo subsequent phase transitions to tetragonal and orthorhombic modifications. These phase transitions are disruptive and result in severely damaged crystals. This paper presents differential thermal analysis data for several prospective solvents, with the aim to identify a system offering the possibility to perform crystal growth of undistorted CaTiO3 crystals by crystallizing them significantly below the melting point directly in the low temperature modification. From mixtures CaF2:TiO2:CaTiO3 = 3:1:1 (molar ratio) the growth of undistorted, at least millimeter-sized CaTiO3 crystals is possible.

Competition between monomeric and dimeric crystals in schematic models for globular proteins.

PubMed

Fusco, Diana; Charbonneau, Patrick

2014-07-17

Advances in experimental techniques and in theoretical models have improved our understanding of protein crystallization. However, they have also left open questions regarding the protein phase behavior and self-assembly kinetics, such as why (nearly) identical crystallization conditions can sometimes result in the formation of different crystal forms. Here, we develop a patchy particle model with competing sets of patches that provides a microscopic explanation of this phenomenon. We identify different regimes in which one or two crystal forms can coexist with a low-density fluid. Using analytical approximations, we extend our findings to different crystal phases, providing a general framework for treating protein crystallization when multiple crystal forms compete. Our results also suggest different experimental routes for targeting a specific crystal form, and for reducing the dynamical competition between the two forms, thus facilitating protein crystal assembly.

Observation of microscopic dynamics of phase transition in ferroelectric crystals using fluorescence spectroscopy

NASA Astrophysics Data System (ADS)

Sedarous, Salah S.

1996-03-01

Despite the large quantity of data on the macroscopic changes in the physical properties of ferroelectric crystals during phase transition, there is a continued need for understanding their microscopic origin. Here we describe a novel method for examining the microscopic dynamics of the ferroelectric phase transition using time-resolved fluorescence spectroscopy. The fluorescence properties of organic chromophores embedded in the ferroelectric crystals triglycine sulfate and potassium dihydrogen phosphate are altered in response to the structural phase transitions. The lifetime and the fractional intensity decay show large changes around Tc and the order of the phase transition is readily recovered (first or second order). To explain the fluorescence lifetime data we present a novel theoretical model based on the concept of polaritons in these crystals. Deactivation of the excited state chromophore involves the participation of the vibrational modes of the chromophore. These modes are coupled to the polarization dispersion of the matrix and facilitate the coupling of the excited state to the collective modes in the crystal. The net result is the flow of energy from the excited state chromophore to the lattice phonon. The data indicate that changes in fluorescence lifetime can be used to examine directly the collective modes in these crystals. Our work provides important insight into the emergence of macroscopic phase transition behavior out of microscopic fluctuations.

Dielectric, magnetic, and lattice dynamics properties of Y-type hexaferrite Ba{sub 0.5}Sr{sub 1.5}Zn{sub 2}Fe{sub 12}O{sub 22}: Comparison of ceramics and single crystals

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

Kamba, S.; Goian, V.; Savinov, M.

2010-05-15

We prepared multiferroic Y-type hexaferrite Ba{sub 0.5}Sr{sub 1.5}Zn{sub 2}Fe{sub 12}O{sub 22} ceramics and compared their magnetic and dielectric properties with single crystal. Magnetic susceptibility and microwave resonance measurement revealed magnetic phase transition at T{sub C}=312 K, similar as in single crystal. Ferroelectric (FE) phase can be induced by external magnetic field in all investigated samples and the phase diagram in ceramics qualitatively resembles that of the single crystal. The range of magnetic fields, where the FE phase is induced, broadens after annealing of single crystal. Ceramics quenched after sintering exhibit several orders of magnitude lower conductivity than the single crystal.more » Heavily damped magnetic resonance was discovered in terahertz spectra at 10 K and its frequency softens below 5 GHz near T{sub C}. Number and symmetry of observed infrared (IR) and Raman active phonons correspond to paraelectric phase with D{sub 3d}{sup 5} hexagonal structure. No evidence for a structural phase transition was found in the IR and Raman spectra on cooling (in zero magnetic field) or in the room-temperature IR spectra with external static magnetic field up to 0.3 T.« less

Synthesis of Self-Bonded Pellets of ETS-4 Phase by New Methodology of Preparation

NASA Astrophysics Data System (ADS)

De Luca, P.; Mastroianni, C.; Nagy, J. B.

2018-06-01

We hereby present the results of a research in order to prepare self-bonded pellets of ETS-4 phase by a new methodology of preparation. In particular, the pellets were prepared by kneading crystals of ETS-4 phase and a dry gel, the latter being the precursor for the synthesis of the ETS-4 phase crystals. One of the innovative aspects that is proposed and highlighted in this work is represented by the fact that the dry-gel acts as a “binder”. It is characterized by the same chemical composition of crystals, thus avoiding contamination with other elements. In addition, dry-gel allows, the promotion of nucleation phenomena and thus the formation of new crystals of ETS-4 during the pellets baking phases. The pellets were characterized by X-ray diffraction (XRD), Electron microscopy (SEM) and mechanical strength by hardness tester.

Solvent effects and polymorphic transformation of organic nonlinear optical crystal L-pyroglutamic acid in solution growth processes . I. Solvent effects and growth morphology

NASA Astrophysics Data System (ADS)

Wang, W. S.; Aggarwal, M. D.; Choi, J.; Gebre, T.; Shields, Angela D.; Penn, Benjamin G.; Frazier, Donald O.

1999-03-01

Single crystals of a new promising nonlinear optical material for the tunable UV harmonic generation, L-pyroglutamic acid 60×20×20 mm 3 in size were obtained from aqueous solution by using the temperature-lowering method. Solubility of L-pyroglutamic acid in different solvents was measured. The single crystals showed different morphological characteristics and growth rate in different solvents with different crystallographic orientations. Methanol or ethanol solutions yielded needle-like crystals. In mixed solution such as methanol/H 2O or ethanol/ H 2O plate-like crystals with a thickness in the direction [0 1 0] were observed. The water as a good solvent, however, produced long prism-like crystals. The two polymorphs of L-pyroglutamic acid (α and β phases) were found for the first time. The growth shapes of α-phase is mainly a prism and β phases is a rhombic plate.The growth rate of α and β phases is mainly a function of the supersaturation of the L-pyroglutamic acid in solution.

Growth and structural characterization of large superconducting crystals of La 2 - x Ca 1 + x Cu 2 O 6

DOE PAGES

Schneeloch, J. A.; Guguchia, Z.; Stone, M. B.; ...

2017-12-01

Lmore » arge crystals of a 2 - x Ca 1 + x Cu 2 O 6 (a-Ca-2126) with x = 0:10 and 0.15 have been grown and converted to bulk superconductors by high-pressure oxygen annealing. The superconducting transition temperature, T c, is as high as 55 K; this can be raised to 60 K by post-annealing in air. Here we present structural and magnetic characterizations of these crystals using neutron scattering and muon spin rotation techniques. While the as-grown, non-superconducting crystals are single phase, we nd that the superconducting crystals contain 3 phases forming coherent domains stacked along the c axis: the dominant a-Ca-2126 phase, very thin (1.5 unit-cell) intergrowths of a 2CuO 4, and an antiferromagnetic a 8Cu 8O 20 phase. We propose that the formation and segregation of the latter phases increases the Ca concentration of the a-Ca-2126, thus providing the hole-doping that supports superconductivity.« less

Growth and structural characterization of large superconducting crystals of La 2 - x Ca 1 + x Cu 2 O 6

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

Schneeloch, J. A.; Guguchia, Z.; Stone, M. B.

Lmore » arge crystals of a 2 - x Ca 1 + x Cu 2 O 6 (a-Ca-2126) with x = 0:10 and 0.15 have been grown and converted to bulk superconductors by high-pressure oxygen annealing. The superconducting transition temperature, T c, is as high as 55 K; this can be raised to 60 K by post-annealing in air. Here we present structural and magnetic characterizations of these crystals using neutron scattering and muon spin rotation techniques. While the as-grown, non-superconducting crystals are single phase, we nd that the superconducting crystals contain 3 phases forming coherent domains stacked along the c axis: the dominant a-Ca-2126 phase, very thin (1.5 unit-cell) intergrowths of a 2CuO 4, and an antiferromagnetic a 8Cu 8O 20 phase. We propose that the formation and segregation of the latter phases increases the Ca concentration of the a-Ca-2126, thus providing the hole-doping that supports superconductivity.« less