bluuebunny/crossref_metadata_2025 huggingface dataset:
An update on the use of indacaterol in patients with COPD
Authors: Brienza Nadia S. , Amor-Carro Óscar , Ramos-Barbón David
Published: November 2010

Current guidelines for the management of chronic obstructive pulmonary disease (COPD) establish that bronchodilator medications are central to the symptomatic treatment of the disease. Regular treatment with long-acting bronchodilators is recommended as more effective and convenient than short-acting bronchodilators, because the long-acting agents provide greater bronchodilator efficacy and symptomatic relief, increased tolerance to exercise, and improved rate of exacerbations and quality of life test scores. Dosing regimens requiring less frequent dosing also provide improved treatment compliance. Indacaterol is a novel once-daily ultra-long-acting β2-agonist bronchodilator now approved in the European Union for maintenance bronchodilator treatment of airflow obstruction in adult patients with COPD, to be administered as 150 or 300 µg once-daily dose by means of a single-dose dry powder inhaler. This review focuses on providing a clinical practice-oriented synopsis of the data generated from the randomized trials during the clinical development of indacaterol, published as of the time of writing. Indacaterol has been shown to provide effective 24-h bronchodilation and a fast onset of action, with an efficacy at least comparable or superior to current bronchodilator therapy standards and with a favourable safety and tolerability profile within the β2-agonist drug class.
Validated instruments used to measure attitudes of healthcare students and professionals towards patients with physical disability: a systematic review
Authors: Lam Wai Yim , Gunukula Sameer K , McGuigan Denise , Isaiah New , Symons Andrew B , Akl Elie A
Published: November 2010

Background

Instruments to detect changes in attitudes towards people with disabilities are important for evaluation of training programs and for research. While we were interested in instruments specific for medical students, we aimed to systematically review the medical literature for validated survey instruments used to measure attitudes of healthcare students and professionals towards patients with physical disability.

Methods

We electronically searched Medline, EMBASE, PsycINFO, Health and Psychosocial Instruments. We included papers reporting on the development and/or validation of survey instruments to measure attitudes of healthcare students and professionals towards patients with physical disability. We excluded papers in which the attitudes were not measured in a provider-patient context. Two reviewers carried out titles and abstracts screening, full texts screening, and data abstraction in a duplicate and independent manner using standardized and pilot tested forms.

Results

We identified seven validated survey instruments used for healthcare students and professionals. These instruments were originally developed for the following target populations: general population (n = 4); dental students (n = 1); nursing students (n = 1); and rehabilitation professionals (n = 1). The types of validity reported for these instruments were content validity (n = 3), criterion-related validity (n = 1), construct validity (n = 2), face validity (n = 1), discriminant validity (n = 1), and responsiveness (n = 1). The most widely validated and used tool (ATDP) was developed in the late 1960s while the most recent instrument was developed in the early 1990s.

Conclusion

Of the seven identified validated instruments, less than half were specifically designed for healthcare students and professionals and none for medical students. There is a need to develop and validate a contemporary instrument specifically for medical students.
Admixture mapping of end stage kidney disease genetic susceptibility using estimated mutual information ancestry informative markers
Authors: Shlush Liran I , Bercovici Sivan , Wasser Walter G , Yudkovsky Guennady , Templeton Alan , Geiger Dan , Skorecki Karl
Published: November 2010

Background

The question of a genetic contribution to the higher prevalence and incidence of end stage kidney disease (ESKD) among African Americans (AA) remained unresolved, until recent findings using admixture mapping pointed to the association of a genomic locus on chromosome 22 with this disease phenotype. In the current study we utilize this example to demonstrate the utility of applying a multi-step admixture mapping approach.

Methods

A multi-step case only admixture mapping study, consisted of the following steps was designed: 1) Assembly of the sample dataset (ESKD AA); 2) Design of the estimated mutual information ancestry informative markers (n = 2016) screening panel 3); Genotyping the sample set whose size was determined by a power analysis (n = 576) appropriate for the initial screening panel; 4) Inference of local ancestry for each individual and identification of regions with increased AA ancestry using two different ancestry inference statistical approaches; 5) Enrichment of the initial screening panel; 6) Power analysis of the enriched panel 7) Genotyping of additional samples. 8) Re-analysis of the genotyping results to identify a genetic risk locus.

Results

The initial screening phase yielded a significant peak using the ADMIXMAP ancestry inference program applying case only statistics. Subgroup analysis of 299 ESKD patients with no history of diabetes yielded peaks using both the ANCESTRYMAP and ADMIXMAP ancestry inference programs. The significant peak was found on chromosome 22. Genotyping of additional ancestry informative markers on chromosome 22 that took into account linkage disequilibrium in the ancestral populations, and the addition of samples increased the statistical significance of the finding.

Conclusions

A multi-step admixture mapping analysis of AA ESKD patients replicated the finding of a candidate risk locus on chromosome 22, contributing to the heightened susceptibility of African Americans to develop non-diabetic ESKD, and underscores the importance of using mutual information and multiple ancestry inference approaches to achieve a robust analysis, using relatively small datasets of "affected" only individuals. The current study suggests solutions to some limitations of existing admixture mapping methodologies, such as considerations regarding the distribution of ancestry information along the genome and its effects on power calculations and sample size.
Consensus statement of the European guidelines on clinical management of HIV‐1 tropism testing
Authors: Vandekerckhove LPR , Wensing AMJ , Kaiser R , Brun‐Vezinet F , Clotet B , De Luca A , Dressler S , Garcia F , Geretti AM , Klimkait T , Korn K , Masquelier B , Perno CF , Schapiro J , Soriano V , Sönnerborg A , Vandamme ÀM , Verhofstede C , Walter H , Zazzi M , Boucher CA
Published: November 2010

7‐11 November 2010, Tenth International Congress on Drug Therapy in HIV Infection, Glasgow, UK
High level of adherence to HAART among refugees and internally displaced persons on HAART in western equatorial region of Southern Sudan
Authors: Salami O , Buzu A , Nzeme C
Published: November 2010

7‐11 November 2010, Tenth International Congress on Drug Therapy in HIV Infection, Glasgow, UK
Development of a single‐tube, low‐cost, analytical process to extract, separate and determine efavirenz and rifampicin plasma concentrations in HIV/TB co‐infected patients
Authors: Fox D , O’Connor R , Mallon P , McMahon G
Published: November 2010

7‐11 November 2010, Tenth International Congress on Drug Therapy in HIV Infection, Glasgow, UK
Population pharmacokinetic modelling of once‐daily ritonavir‐boosted darunavir in HIV‐infected patients
Authors: Dickinson L , Jackson AGA , Garvey LJ , Watson V , Khoo SH , Winston A , Boffito M , Davies GR , Back DJ
Published: November 2010

7‐11 November 2010, Tenth International Congress on Drug Therapy in HIV Infection, Glasgow, UK
Sry: the master switch in mammalian sex determination
Authors: Kashimada Kenichi , Koopman Peter
Published: November 2010

SRY, the mammalian Y-chromosomal testis-determining gene, induces male sex determination. Recent studies in mice reveal that the major role of SRY is to achieve sufficient expression of the related gene Sox9, in order to induce Sertoli cell differentiation, which in turn drives testis formation. Here, we discuss the cascade of events triggered by SRY and the mechanisms that reinforce the differentiation of the testes in males while actively inhibiting ovarian development.
A homeodomain feedback circuit underlies step-function interpretation of a Shh morphogen gradient during ventral neural patterning
Authors: Lek Madelen , Dias José M. , Marklund Ulrika , Uhde Christopher W. , Kurdija Sanja , Lei Qiubo , Sussel Lori , Rubenstein John L. , Matise Michael P. , Arnold Hans-Henning , Jessell Thomas M. , Ericson Johan
Published: November 2010

The deployment of morphogen gradients is a core strategy to establish cell diversity in developing tissues, but little is known about how small differences in the concentration of extracellular signals are translated into robust patterning output in responding cells. We have examined the activity of homeodomain proteins, which are presumed to operate downstream of graded Shh signaling in neural patterning, and describe a feedback circuit between the Shh pathway and homeodomain transcription factors that establishes non-graded regulation of Shh signaling activity. Nkx2 proteins intrinsically strengthen Shh responses in a feed-forward amplification and are required for ventral floor plate and p3 progenitor fates. Conversely, Pax6 has an opposing function to antagonize Shh signaling, which provides intrinsic resistance to Shh responses and is important to constrain the inductive capacity of the Shh gradient over time. Our data further suggest that patterning of floor plate cells and p3 progenitors is gated by a temporal switch in neuronal potential, rather than by different Shh concentrations. These data establish that dynamic, non-graded changes in responding cells are essential for Shh morphogen interpretation, and provide a rationale to explain mechanistically the phenomenon of cellular memory of morphogen exposure.
The prevalence of thyroid disorders during early pregnancy in China: the benefits of universal screening in the first trimester of pregnancy
Authors: Wang Weiwei , Teng Weiping , Shan Zhongyan , Wang Sen , Li Jianxin , Zhu Lin , Zhou Jin , Mao Jinyuan , Yu Xiaohui , Li Jia , Chen Yanyan , Xue Haibo , Fan Chenling , Wang Hong , Zhang Hongmei , Li Chenyang , Zhou Weiwei , Gao Bo , Shang Tao , Zhou Jiaren , Ding Bin , Ma Ying , Wu Ying , Xu Hui , Liu Wei
Published: November 2010

Context

Maternal thyroid disorders during early pregnancy can influence pregnancy outcome and fetal development. The recent Endocrine Society Clinical Practice Guideline recommends a case-finding approach in which pregnant women who are at high risk for developing thyroid disease are tested.

Objective

The purpose of this study was to use the first trimester-specific reference intervals of thyroid-related hormones to explore the prevalence of thyroid dysfunction during early pregnancy and to analyze effectiveness of different screening strategies.

Design

A multicenter cohort study.

Method

A total of 2899 pregnant women were enrolled in this study during their first trimester of gestation. Levels of TSH, free thyroxine, free triiodothyronine, and thyroid peroxidase antibodies (TPOAb) were measured and thyroid disorders of pregnant women were diagnosed based on the first trimester-specific reference intervals.

Results

The prevalence of hypothyroidism was significantly higher in the high-risk group than in the non-high-risk group (10.9 vs 7.0%, χ2=7.1, P=0.008). The prevalence of hyperthyroidism was not significantly different between the high-risk group and the non-high-risk group (2.7 vs 1.6%, χ2=2.27, P=0.13). Elevated levels of TPOAb and a personal history of thyroid disease increased the risk of thyroid dysfunction.

Conclusions

A case-finding strategy for screening thyroid function in the high-risk group would miss about 81.6% pregnant women with hypothyroidism and 80.4% pregnant women with hyperthyroidism.
One Hundred Years of Pleiotropy: A Retrospective
Authors: Stearns Frank W
Published: November 2010

Pleiotropy is defined as the phenomenon in which a single locus affects two or more distinct phenotypic traits. The term was formally introduced into the literature by the German geneticist Ludwig Plate in 1910, 100 years ago. Pleiotropy has had an important influence on the fields of physiological and medical genetics as well as on evolutionary biology. Different approaches to the study of pleiotropy have led to incongruence in the way that it is perceived and discussed among researchers in these fields. Furthermore, our understanding of the term has changed quite a bit since 1910, particularly in light of modern molecular data. This review traces the history of the term “pleiotropy” and reevaluates its current place in the field of genetics.
Genetic Evidence That Polysumoylation Bypasses the Need for a SUMO-Targeted Ub Ligase
Authors: Mullen Janet R , Das Mukund , Brill Steven J
Published: November 2010

Saccharomyces cerevisiae cells lacking the Slx5–Slx8 SUMO-targeted Ub ligase display increased levels of sumoylated and polysumoylated proteins, and they are inviable in the absence of the Sgs1 DNA helicase. One explanation for this inviability is that one or more sumoylated proteins accumulate to toxic levels in sgs1Δslx5Δ cells. To address this possibility, we isolated a second-site suppressor of sgs1Δslx5Δ synthetic lethality and identified it as an allele of the ULP2 SUMO isopeptidase. The suppressor, ulp2–D623H, behaved like the ulp2Δ allele in its sensitivity to heat, DNA replication stress, and DNA damage. Surprisingly, deletion of ULP2, which is known to promote the accumulation of poly-SUMO chains, suppressed sgs1Δslx5Δ synthetic lethality and the slx5Δ sporulation defect. Further, ulp2Δ's growth sensitivities were found to be suppressed in ulp2Δslx5Δ double mutants. This mutual suppression indicates that SLX5–SLX8 and ULP2 interact antagonistically. However, the suppressed strain sgs1Δslx5Δulp2–D623H displayed even higher levels of sumoylated proteins than the corresponding double mutants. Thus, sgs1Δslx5Δ synthetic lethality cannot be due simply to high levels of bulk sumoylated proteins. We speculate that the loss of ULP2 suppresses the toxicity of the sumoylated proteins that accumulate in slx5Δ–slx8Δ cells by permitting the extension of poly-SUMO chains on specific target proteins. This additional modification might attenuate the activity of the target proteins or channel them into alternative pathways for proteolytic degradation. In support of this latter possibility we find that the WSS1 isopeptidase is required for suppression by ulp2Δ.
Winter Cover Crops Affect Monoculture Maize Yield and Nitrogen Leaching under Irrigated Mediterranean Conditions
Authors: Salmerón Montserrat , Cavero José , Quílez Dolores , Isla Ramón
Published: November 2010

Under semiarid Mediterranean conditions irrigated maize (Zea mays L.) has been associated with nitrate pollution of surface water and groundwater. Cover crops grown during the intercrop period of maize could reduce N leaching. A 2‐yr experiment was conducted in drainage lysimeters with three cover crops: barley (Hordeum vulgare L), winter rape (Brassica rapa L.), or common vetch (Vicia sativa L.). Bare soil was used as control treatment. Maize was fertilized with 300 kg ha−1 N in the control, and this amount was reduced after a cover crop according to the N content in the aboveground cover crop biomass. Barley and winter rape biomass had a higher N content than vetch (130–170 vs. 50 kg ha−1). The vetch treatment did not reduce N leaching or affect maize yield. The barley and winter rape treatments reduced N leaching by 80% compared to the control (25 kg ha−1 yr−1) mainly due to a reduction of NO3–N concentration in drainage. Maize yield was reduced by 2.7 Mg ha−1 after barley and winter rape but still high (≈14 Mg ha−1). This reduction was due to an N deficiency caused by lower soil N in spring after the cover crop and insufficient N mineralization and/or lack of synchronization with maize N uptake. To use nonlegume winter cover crops to reduce N leaching in monoculture maize it is necessary to consider that N mineralization may not be sufficient to fulfill maize N requirements and N fertilizer adjustment tools should be developed.
Double‐Cropping Sorghum for Biomass
Authors: Goff Ben M. , Moore Kenneth J. , Fales Steven L. , Heaton Emily A.
Published: November 2010

Double‐cropping systems have been suggested as a way to increase annual dry matter production per hectare, while simultaneously delivering environmental benefits. Past research seems to indicate that there is a genotypic effect for the suitability of a crop for use within double‐cropping systems; however, despite sorghum's [Sorghum bicolor (L.) Moench] diverse genetic background, there has not been a great deal of work done to explore this response for this crop. Twelve sorghum varieties were grown as sole crops and within a double‐cropping system with winter triticale [× Triticosecale Wittmack] in central and northern Iowa. Results showed that although the single‐cropping system produced slightly higher biomass yields, there were no significant differences in total production between the two systems for several of the sorghum varieties. These varieties were characterized as earlier maturing ones that had nearly maximized dry matter production at the time of harvest for the double‐cropping system, and thus, any potential loss in sorghum yield was supplemented by the biomass production from the triticale crop. However when the chemical composition of the crops was considered, the theoretical ethanol yield of the single‐cropping system was greater than the double‐cropping system for all sorghum varieties. Although triticale was capable of offsetting any potential loss in dry matter, as an ethanol feedstock it was inferior to sorghum.
Adapting CROPGRO for Simulating Spring Canola Growth with Both RZWQM2 and DSSAT 4.0
Authors: Saseendran S. A. , Nielsen D. C. , Ma L. , Ahuja L. R.
Published: November 2010

Currently, canola (Brassica napus L.) is gaining importance as a potential feedstock in biodiesel production industries, increasing the demand for canola production acreage. Agricultural system models that simulate canola growth and yield will help to assess the feasibility of canola production under various agroclimatic conditions. In this study, we adapted the CROPGRO model for simulation of spring canola in both Root Zone Water Quality Model (RZWQM2) and Decision Support System for Agrotechnology Transfer (DSSAT 4.0). Soil water, phenology, leaf area index (LAI), biomass, plant height, and grain yield data from irrigation experiments conducted in 2005 on a Weld silt loam soil (fine, smectitic, mesic Aridic Argiustoll) in the semiarid climate at Akron, CO were used for model parameterization and calibration. Similar data from 1993, 1994, and 2006 were used for validation. Species and cultivar parameters for canola were developed using data from literature or by calibrating the existing CROPGRO‐faba bean (Vicia faba L.) parameters. Grain yields across various irrigation levels and seasons were simulated reasonably well by RZWQM2 with root mean square error (RMSE) of 215 kg ha−1 and index of agreement (d) of 0.98. Seasonal biomass development was simulated with RMSEs between 341 and 903 kg ha−1, d between 0.55 and 0.99, and R2 between 0.85 and 0.98. The CROPGRO‐canola parameters developed were also tested within the DSSAT 4.0 cropping systems model and found to produce results with similar accuracy.
Noninvasive MR characterization of structural and functional components of reperfused infarct
Authors: Saeed Maythem , Martin Alastair J. , Saloner David , Do Loi , Wilson Mark
Published: November 2010

Background: Left ventricular (LV) remodeling is a highly complex phenomenon that starts soon after infarction and progresses to extensive regional and global architectural changes over time.

Purpose: To noninvasively comprehensively characterize transient (edema, hemorrhage, microvascular obstruction (MO)) and persistent structural (infarct size) components of reperfused infarct up to 10 weeks and to determine their relation to LV function.

Material and Methods: Farm pigs were used for the study. Under fluoroscopy the left anterior descending (LAD) coronary artery was occluded for 90 min. MR imaging was performed at 3 days ( n=14 pigs), 5 weeks ( n=10), and 10 weeks ( n=6) after reperfusion. The following MR imaging sequences were used: (i) cine; (ii) T2-weighted turbo spin echo; (iii) T2*-weighted turbo spin echo; (iv) tagged; (v) phase-contrast velocity-encoded; (vi) first-pass perfusion; and (vii) delayed contrast-enhanced (DE-MR imaging). After imaging, animals were euthanized at 3 days ( n=4), 5 weeks ( n=4), and 10 weeks ( n=6) and hearts were stained with triphenyltetrazolium chloride to define acute, subacute, and scar infarct and interstitial hemorrhage.

Results: T2, T2*, and DE-MR imaging demonstrated transient interstitial edema, interstitial hemorrhage, and MO, respectively. MO was observed in 85% of animals and 60% of these showed hemorrhages. Cine, tagged, and phase-contrast velocity-encoded images documented the persistent impairment in 3D strain of infarcted segments, which on first-pass perfusion showed persistent perfusion deficit. MR imaging demonstrated the progressive increase in LV volumes and decreased ejection fraction over time. The changes in LV between 5 and 10 weeks were not related to the presence of interstitial edema, interstitial hemorrhage, MO or increase in infarct size.

Conclusion: The various MR sequences described in this study allowed the demonstration of transient and persistent components of reperfused infarct. The progressive deterioration of global LV function was not related to the transient reperfusion components (edema, hemorrhage or MO) or change in infarct size. The results imply that MR imaging has the potential to identify progressive deterioration of LV function unrelated to reperfusion injury components or infarct size.
Jak2 Tyrosine Kinase: A Potential Therapeutic Target for AT1 Receptor Mediated Cardiovascular Disease
Authors: Kirabo Annet , Sayeski Peter P.
Published: November 2010

Patients with hypertension often manifest a dysregulated renin-angiotensin-aldosterone system (RAAS). Most of the available treatment approaches for hypertension are targeted towards the RAAS including direct renin inhibition, ACE inhibition, angiotensin II type 1 receptor (AT1-R) blockade, and aldosterone receptor antagonism. The Jak2 signaling pathway is intricately coupled to the AT1-R signaling processes involved in hypertension. Here, we review the involvement of Jak2 in the pathogenesis of hypertension, and its potential as a therapeutic target for treatment of AT1-R mediated cardiovascular disease. Jak2 may provide a rational therapeutic approach for patients whose blood pressure is not controlled by standard therapies.
The Use of Natural Polymers in Tissue Engineering: A Focus on Electrospun Extracellular Matrix Analogues
Authors: Sell Scott A. , Wolfe Patricia S. , Garg Koyal , McCool Jennifer M. , Rodriguez Isaac A. , Bowlin Gary L.
Published: November 2010

Natural polymers such as collagens, elastin, and fibrinogen make up much of the body’s native extracellular matrix (ECM). This ECM provides structure and mechanical integrity to tissues, as well as communicating with the cellular components it supports to help facilitate and regulate daily cellular processes and wound healing. An ideal tissue engineering scaffold would not only replicate the structure of this ECM, but would also replicate the many functions that the ECM performs. In the past decade, the process of electrospinning has proven effective in creating non-woven ECM analogue scaffolds of micro to nanoscale diameter fibers from an array of synthetic and natural polymers. The ability of this fabrication technique to utilize the aforementioned natural polymers to create tissue engineering scaffolds has yielded promising results, both in vitro and in vivo, due in part to the enhanced bioactivity afforded by materials normally found within the human body. This review will present the process of electrospinning and describe the use of natural polymers in the creation of bioactive ECM analogues in tissue engineering.
Increased B7-H1 Expression on Dendritic Cells Correlates with Programmed Death 1 Expression on T Cells in Simian Immunodeficiency Virus-Infected Macaques and May Contribute to T Cell Dysfunction and Disease Progression
Authors: Xu Huanbin , Wang Xiaolei , Pahar Bapi , Moroney-Rasmussen Terri , Alvarez Xavier , Lackner Andrew A. , Veazey Ronald S.
Published: November 2010

Suppression of dendritic cell (DC) function in HIV-1 infection is thought to contribute to inhibition of immune responses and disease progression, but the mechanism of this suppression remains undetermined. Using the rhesus macaque model, we show B7-H1 (programmed death [PD]-L1) is expressed on lymphoid and mucosal DCs (both myeloid DCs and plasmacytoid DCs), and its expression significantly increases after SIV infection. Meanwhile, its receptor, PD-1, is upregulated on T cells in both peripheral and mucosal tissues and maintained at high levels on SIV-specific CD8+ T cell clones in chronic infection. However, both B7-H1 and PD-1 expression in SIV controllers was similar to that of controls. Expression of B7-H1 on both peripheral myeloid DCs and plasmacytoid DCs positively correlated with levels of PD-1 on circulating CD4+ and CD8+ T cells, viremia, and declining peripheral CD4+ T cell levels in SIV-infected macaques. Importantly, blocking DC B7-H1 interaction with PD-1+ T cells could restore SIV-specific CD4+ and CD8+ T cell function as evidenced by increased cytokine secretion and proliferative capacity. Combined, the results indicate that interaction of B7-H1–PD-1 between APCs and T cells correlates with impairment of CD4+ Th cells and CTL responses in vivo, and all are associated with disease progression in SIV infection. Blockade of this pathway may have therapeutic implications for HIV-infected patients.
Organic and Inorganic Blocking Layers for Solution‐Processed Colloidal PbSe Nanocrystal Infrared Photodetectors
Authors: Sarasqueta Galileo , Choudhury Kaushik Roy , Subbiah Jegadesan , So Franky
Published: November 2010

A PbSe solution‐processed nanocrystal‐based infrared photodetector incorporating carrier blocking layers is demonstrated, and significant reduction of dark current is achieved. Detectivity values close to 1012 Jones are achieved by using poly[(9,9′‐dioctylfluorenyl‐2,7‐diyl)‐co‐(4,4′‐(N‐(4‐sec‐butyl))diphenylamine)] (TFB) and ZnO nanocrystals (NC) as the electron blocker and hole blocker, respectively. An improvement in lifetime is also observed in the devices with the ZnO NCs hole blocking layer.
Chemically Stable Pr and Y Co‐Doped Barium Zirconate Electrolytes with High Proton Conductivity for Intermediate‐Temperature Solid Oxide Fuel Cells
Authors: Fabbri Emiliana , Bi Lei , Tanaka Hidehiko , Pergolesi Daniele , Traversa Enrico
Published: November 2010

A chemically stable and highly proton‐conductive electrolyte is developed by partially substituting the Zr site of Y‐doped barium zirconate (BZY) with 10 mol% of Pr. Compared to BZY, BaZr0.7Pr0.1Y0.2O3‐δ (BZPY) shows improved sinterability as revealed by dilatometric measurements and scanning electron microscopy (SEM) analysis. Dense samples are obtained after sintering at 1500˚C for 8 h. Moreover, BZPY shows good chemical stability in the wide range of fuel‐cell operating conditions. The larger density and the enhanced grain growth, compared to BZY, allow the volume content of grain boundaries, which generally show a high resistance for proton transport, to be reduced and, thus, a high proton conductivity can be achieved in the temperature range of interest for practical applications (above 10−2 Scm−1 at 600˚C). The good sinterability, chemical stability, and high conductivity of the BZPY electrolyte enabled the fabrication of single‐cell prototypes based on a thin BZPY membrane by a simple and cost‐saving co‐pressing method. Electrochemical impedance spectroscopy (EIS) analysis performed during fuel‐cell tests under open‐circuit conditions confirms the good electrical performance of BZPY as electrolyte material. To improve the present fuel‐cell performance adapted cathode materials for this BZPY electrolyte need to be developed.
Preparation and characterization of polyamide reverse‐osmosis membranes with good chlorine tolerance
Authors: Son Seung Hee , Jegal Jonggeon
Published: November 2010

To prepare reverse‐osmosis membranes with good permeation properties and good chlorine tolerance, polyamide (PA) composite membranes were prepared with a conventional interfacial polymerization method. Diamine compounds, including metaphenylene diamine (MPD), 2,6‐diaminotoluene (2,6‐DAT), 2,4‐diaminotoluene, 3,4‐diaminotoluene, 2,4‐diaminoanisol, 4‐chlorometaphenylene diamine, and N,N′‐diphenylethyldiamine, were polymerized with trimesoyl chloride (TMC) or isophthaloyl chloride to form PA polymers. The polymers were then tested for chlorine tolerance and hydrophilicity. Among the diamines tested, 2,6‐DAT and MPD were used for the formation of thin‐film composite (TFC) membranes by their interfacial polymerization with TMC on the surface of microporous polysulfone supports. Their performance and chlorine tolerance were test under various conditions. The TFC membranes prepared from 2,6‐DAT and TMC showed better chlorine tolerance than the membrane prepared from MPD and TMC, and the permeation properties of these membranes were comparable to each other. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Nanocomposite polyvinyl alcohol fibers for medical applications
Authors: Mikołajczyk Teresa , Rabiej Stanisław , Boguń Maciej , Szparaga Grzegorz , Draczyński Zbigniew
Published: November 2010

It was investigated how the HAp and SiO2 nanoadditives introduced into the material of fibers made from polyvinyl alcohol (PVA) affects the structure, sorption, and strength properties of those fibers. The conditions of the fibers' production were selected with the aim of obtaining the nanocomposite PVA fibers which would be soluble in water and in body fluids. These fibers are intended to be used for the production of a biocomposite with another biodegradable polymer. The determination was made of the effect of two different deformations applied at the fiber production stage on the structure and properties of the fibers. Using the WAXS method, the supramolecular structure of the fibers was determined. Nanocomposite PVA fibers obtained in this work have an oriented crystalline structure with a rather low level of crystallinity, reaching 40%, and a relatively high orientation index of crystallites: 0.48–0.54. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Semiconductive Conjugated Polymers
Authors: Koßmehl Gerhard
Published: November 2010

A review is given about the syntheses and electrical properties of conjugated poly(arylenevinylenes), poly(arylenebutadienylenes), poly‐(arylenepolyenylenes), polymeric cyanine dyes, polymeric azomethines, and polymeric azines. All these polymers are organic semiconductors and photoconductors. — Variations in chemical structure cause changes in the electrical conductivities: Electron donating substituents in aromatic units respectively heteroaromatic electron excess systems give rise to enhanced electrical conductivities whereas electron accepting substituents respectively heteroaromatic electron deficient systems effect in the opposite direction. Generally the nitrogen containing polymers have lower electrical conductivities. Surprisingly polymeric azomethines prepared from aromatic diamines with electron deficient systems respectively from aromatic diamines with electron accepting substituents have higher electrical conductivities than ordinary polymeric azomethines.
Ion Diffusion in the 2d‐System AgxTaS2: In situ Observation of Electrointercalation and Homogenisation
Authors: Ramos C. , Lerf A. , Butz T.
Published: November 2010

We monitored the nuclear quadrupole interaction (NQI) of 181Ta by perturbed angular correlation in AgxTaS2 crystals both in situ during electrointercalation and upon subsequent homogenisation up to 1100 K. The electrointercalation starts with the simultaneous formation of two 2nd stage phases differing in Ag lattice site occupation. Homogenisation of Ag0.18TaS2 and Ag0.38TaS2 yields valuable information on the miscibility gaps and gives evidence for Daumas‐Hérold defects.
Solid State Reactions Between Silicon Carbide and Various Transition Metals
Authors: Backhaus‐Ricoult M.
Published: November 2010

The chemical interfacial reaction between silicon carbide and transition metals (Ti, Fe, Ni, (Fe, Ni)‐alloys) has been studied in order to better understand the reaction mechanism taking place and model it using the available thermodynamics and kinetics data of the reacting systems. Titanium silicide and titanium carbide have been identified by microprobe, X‐ray techniques and scanning electron microscopy as being phases resulting of the reaction between silicon carbide and titanium. In the same way, reaction between SiC and nickel yields nickel silicides and graphite, whereas the reaction between SiC and iron leads to the build‐up of silicon rich alloys and graphite.
The Determination of Translational Intracrystalline Diffusion Constants of Molecules in Faujasite‐Type Zeolites with the Aid of Deuteron‐NMR‐Spectroscopy
Authors: Burmeister R. , Schwarz H. , Boddenberg B.
Published: November 2010

From the shapes and widths of the deuteron liquid and solid state spectra of benzene, p‐xylene and ethene sorbed in the zeolites NaX, AgNaX, and NaY the dynamics of the anisotropic reorientational and of the site exchange motions are assessed. Intracrystalline diffusivities are obtained which are generally lower in NaY than in NaX.
7Li NMR Spin‐Lattice Relaxation and Ionic Diffusion in Lithium Thioborate Glasses
Authors: Grüne M. , Meierkord H. , Müller‐Warmuth W. , Hebel P. Zum , Krebs B. , Wulff M.
Published: November 2010

7Li NMR spin‐lattice relaxation rates at 16 MHz and 117 MHz have been measured at various temperatures for glasses in the non‐oxide chalcogenide system B2S3 — Li2S — LiX with X = Cl, Br, I. As compared with the corresponding oxide glasses these materials are distinguished by a higher ionic conductivity, and the relaxation maxima are better accessible. The relaxation rates display anomalous temperature and frequency dependences. Attempts to interpret the non‐BPP‐type relaxation in terms of appropriate diffusion models are discussed.
Non‐Periodic Local Motion of Silver Ions in β‐Ag3SI
Authors: Funke K. , Kantimm Th. , Maue Th. , Zurwellen D. , Seebode J. , Zachmann G.
Published: November 2010

The electrical conductivity of pressed pellets of β‐Ag3SI has been measured at frequencies from 107 Hz to 1013 Hz, at 295 K. Below 2 · 109 Hz the conductivity is found to be constant. At higher frequencies it increases, attaining a v2 frequency dependence at about 4 · 1010 Hz and eventually displaying a broad maximum centred at ca. 6 · 1011 Hz. Above 1012 Hz we observe the excitation of transverse optical phonons. ‐ In the 1010 Hz to 1010 Hz frequency regime the experimental conductivity is compared with conductivity spectra calculated on the basis of the following simple single‐particle models: (I) Brownian motion in a two‐dimensional harmonic potential, (ii) a microscopically reversible version of a two‐dimensional type of localized diffusion. In either treatment. the local motion turns out to be non‐periodic.
Defect Concentration Relaxation During Interdiffusion Between MnO and FeO
Authors: Schmalzried H. , Ueshima Y.
Published: November 2010

For the diffusional equilibration process between crystals of MnO and FeO it was investigated how far the usual assumption of local thermodynamic point defect equilibrium holds (given the intensive variables, T, P, and μo2 (gas)). To this end, accurate component concentration profiles which were normalized for the given linear diffusion geometry with t, have been determined. From the fact that these profiles do not coincide for different diffusion times it is concluded that deviations from the local point defect equilibrium occur. The largest deviations are found at the beginning of the interdiffusion process. The point defect relaxation (cation vacancy annihilation) takes place preferentially at the outer surfaces of the crystals, which have access to the oxygen gas atmosphere. — These cation vacancy processes can be studied directly with the help of a solid state galvanic cell, in which the evolving oxygen gas from the crystal surface is coulometrically titrated. The experimental data are in accordance with theoretical calculations which have been performed in order to understand under which conditions point defect concentration relaxation has an influence on chemical interdiffusion processes.
Dispersive Energy Transport in Disordered Molecular Crystals
Authors: Von Borczyskowski C. , Kirski T.
Published: November 2010

Chemically mixed molecular crystals of dichlorobenzene (DCB) in dibromobenzene (DBB) exhibit dispersive energy transport within the DCB sublattice. With increasing DCB concentration dynamic percolation is observed at cp = 4.5%. Above cp a Kohlrausch‐type relaxation reveals the fractal spectral dimension ds ≈ 4/3 when assuming a superimposed waiting time distribution parameter γ = 1/2.
Spectral Hole‐Burning: Applications to Optical Image Storage
Authors: Caro Cosimo De , Renn Alois , Wild Urs P.
Published: November 2010

Spectral hole‐burning was used to record information in the inhomogeneous broadened absorption band of free base chlorin in polyvinylbutyral at 1.7 K. The wavelength multiplexing property of these materials allows to store many images in the form of holograms in a single spot of about 5 mm diameter. The gray level pattern of the image is translated into a pattern of a spatially varying hole depth. Such a storage device can be considered three‐dimensional, involving the two spatial dimensions of the thin sample film and the dimension of the optical wavelength. If in addition an electric field is applied, a four‐dimensional storage device is created having two spatial, one wavelength and one electric field dimensions. Addressing a specific image is achieved by merely adjusting the read‐out wavelength and the value of the electric field to the values used during the storage process. No moving parts are involved at all. It is demonstrated that in chlorin at least 25 images can be stored in a single 1 cm−1 interval and in the electric field range of ± 100 kV/cm.
Trends in bioanalytical methods for the determination and quantification of club drugs: 2000–2010
Authors: Brown Stacy D. , Melton Tyler C.
Published: November 2010

The term ‘club drug’ can be loosely defined as any substance used to enhance social settings. Such drugs are commonly found at raves or similar all‐night dance parties and include methamphetamine, 3,4‐methylenedioxymethamphetamine, gamma‐hydroxybutyrate (GHB), ketamine (KET), and flunitrazepam (FLU). These drugs have potentially dangerous side effects including hallucinations, paranoia, amnesia and hyperthermia. In addition, GHB, KET and FLU are considered predatory drugs due to their roles in drug‐facilitated sexual assault. Forensic and regulatory agencies routinely have the need for determination and accurate quantification of these drugs in biological fluids, especially in cases of mortality or criminal investigations. This review presents the chromatographic and spectroscopic methods published for such analyses over the last decade, including sample preparation techniques and validation data. Copyright © 2010 John Wiley & Sons, Ltd.
Mesenchymal stem cells protect islets from hypoxia/reoxygenation‐induced injury
Authors: Lu Yanrong , Jin Xi , Chen Younan , Li Shengfu , Yuan Yu , Mai Gang , Tian Bole , Long Dan , Zhang Jie , Zeng Li , Li Youping , Cheng Jingqiu
Published: November 2010

Hypoxia/reoxygenation (H/R)‐induced injury is the key factor associated with islet graft dysfunction. This study aims to examine the effect of mesenchymal stem cells (MSCs) on islet survival and insulin secretion under H/R conditions. Islets from rats were isolated, purified, cultured with or without MSCs, and exposed to hypoxia (O2 ≤ 1%) for 8 h and reoxygenation for 24 and 48 h, respectively. Islet function was evaluated by measuring basal and glucose‐stimulated insulin secretion (GSIS). Apoptotic islet cells were quantified using Annexin V‐FITC. Anti‐apoptotic effects were confirmed by mRNA expression analysis of hypoxia‐resistant molecules, HIF‐1α, HO‐1, and COX‐2, using semi‐quantitative retrieval polymerase chain reaction (RT‐PCR). Insulin expression in the implanted islets was detected by immunohistological analysis. The main results show that the stimulation index (SI) of GSIS was maintained at higher levels in islets co‐cultured with MSCs. The MSCs protected the islets from H/R‐induced injury by decreasing the apoptotic cell ratio and increasing HIF‐1α, HO‐1, and COX‐2 mRNA expression. Seven days after islet transplantation, insulin expression in the MSC‐islets group significantly differed from that of the islets‐alone group. We proposed that MSCs could promote anti‐apoptotic gene expression by enhancing their resistance to H/R‐induced apoptosis and dysfunction. This study provides an experimental basis for therapeutic strategies based on enhancing islet function. Copyright © 2010 John Wiley & Sons, Ltd.
Drying of Sodium Acetate in a Pulsed Fluid Bed Dryer
Authors: de Souza L. F. G. , Nitz M. , Lima P. A. , Taranto O. P.
Published: November 2010

Sodium acetate crystals obtained from the reaction of acetic acid with sodium hydroxide are usually dried in rotary or fluidized beds. In this study, a batch pulsed fluid bed dryer with a 0.18 m2 cross‐sectional area was used in an attempt to reduce energy consumption and increase productivity. Drying curves of sodium acetate were determined for different conditions: inlet air temperature of 65 and 80 °C and pulsation frequency of 0 rpm (conventional fluidized bed), 500 and 900 rpm (pulsed fluid bed). A 22 factorial design was used to analyze the results. The intermittent flow helped to break agglomerates and provided better contact between particles and the gas. Drying rates were higher under pulsed fluidization when compared to conventional fluidization. Conventional fluidized bed drying consumed 2.5 times more energy at 80 °C. The influence of temperature on the drying rate was also evident.
Extension of the pore diffusion approach for modelling binary adsorption of lead and arsenic ions in a fixed‐bed column packed with atlantic cod fish scales
Authors: Basu A. , Rahaman M. S. , Islam M. R.
Published: November 2010

The removal of lead and arsenic ions using Atlantic Cod (Gadus morhua) fish scale involves ion exchange, chemisorption, and precipitation of its constituents and is competitive with respect to adsorption onto the negatively charged heterogeneous substrates. The nonlinear sorption equilibrium concept is preceded by pore diffusion of the solute and is utilised for numerical modelling of this binary adsorption. Numerical simulation data demonstrate reasonable agreements with experimental results of dynamic column tests. Sensitivity analyses confirm that parameters such as porosity, adsorption coefficient, mobility of ions, and number of sorption sites contribute significantly to breakthrough interval of contaminant in dynamic columns. At lower pH values (7–8.04), the adsorption coefficients of cations such as lead are significantly lower than at pH value of 11.0.
Modification of NAY by LA3+ for the dehydration of lactic acid: The effect of preparation protocol on catalyst microstructure and catalytic performance
Authors: Yu Dinghua , Sun Peng , Tang Zhenchen , Li Zhixian , Huang He
Published: November 2010

La‐modified NaY zeolites have been prepared through impregnation and in situ synthesis methods. The surface structure of the obtained zeolites was then characterised by XRD, UV–Vis DRS, FT‐Far‐IR, Raman spectra, H2‐TPR, N2 adsorption, and NH3‐TPD. The results of the catalytic dehydration reaction of lactic acid showed that the La/NaY catalyst prepared by impregnation method exhibited higher selectivity to acrylic acid than the La–NaY prepared by the in situ synthesis. The characterisation results indicated that the enhanced catalytic performance could be attributed to the difference of La3+ ion location caused by the different preparation protocols, which would influence the electric field distribution of zeolites cages, the reactant adsorption, chemical activation, and the reaction path.

Les zéolithes NaY modifiées avec du lanthane (La) ont été préparées grâce à des méthodes d'imprégnation et de synthèse in situ. La structure de la surface des zéolithes ainsi obtenues a été ensuite caractérisée par DRX, spectrophotomètre UV–VIS DR, FT‐Far‐IR, spectroscopie Raman, réduction thermo‐programmée de H2, adsorption de N2 et désorption thermo‐programmée de NH3. Les résultats de la réaction de déshydratation catalytique de l'acide lactique montrent que le catalyseur La/NAY préparé grâce à la méthode d'imprégnation a fait preuve d'une plus grande sélectivité à l'acide acrylique que le catalyseur La/NAY préparé grâce à la synthèse in situ. Les résultats de caractérisation indiquent que le meilleur rendement catalytique peut être dû aux différences d'emplacement de l'ion La3+ causées par les différents protocoles de préparation, qui peuvent influer sur la distribution du champ électrique des cages de zéolithes, l'adsorption du réactif, l'activation chimique et le chemin réactionnel. Can. J. Chem. Eng. © 2010 Canadian Society for Chemical Engineering
Condensed forms for the symmetric eigenvalue problem on multi‐threaded architectures
Authors: Bientinesi Paolo , Igual Francisco D. , Kressner Daniel , Petschow Matthias , Quintana‐Ortí Enrique S.
Published: November 2010

We investigate the performance of the routines in LAPACK and the Successive Band Reduction (SBR) toolbox for the reduction of a dense matrix to tridiagonal form, a crucial preprocessing stage in the solution of the symmetric eigenvalue problem, on general‐purpose multi‐core processors. In response to the advances of hardware accelerators, we also modify the code in the SBR toolbox to accelerate the computation by off‐loading a significant part of the operations to a graphics processor (GPU). The performance results illustrate the parallelism and scalability of these algorithms on current high‐performance multi‐core and many‐core architectures. Copyright © 2010 John Wiley & Sons, Ltd.
Electrostatic Probes for Studying Transport Properties in Tokamak Plasmas
Authors: Uehara K. , Sadamoto Y. , Amemiya H. , Nagashima Y.
Published: November 2010

Electrostatic probes for measuring the boundary plasma in tokamaks are reviewed and presented. Transport properties in JFT‐2, the ion temperature and the magnetic surface in JFT‐2M and floating potential fluctuations during the strong additional heating in JT‐60 are measured by several types of electrostatic probe the above‐mentioned purposes. The Langmuir probe including the double probe is applied to measure the spatial profile of boundary plasma in JFT‐2. The ion sensitive probe, the rotating cylindrical double probe, the asymmetric double probe and the differential double probe are applied to measure the ion temperature and magnetic surface in JFT‐2M. The reciprocating Langmuir probe applied to JFT‐2M observes the potential and density fluctuations and a new type probe is proposed for the quick diagnostic of core hot plasmas as a development of this probe. The fluctuation observed in JT‐60 is identified to be the ion cyclotron instability of the hot plasma caused by the strong anisotropy of the ion distribution function (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)