bluuebunny/crossref_metadata_2025_split huggingface dataset:
Detection of Liquid Water in PEM Fuel Cells' Channels: Design and Validation of a Microsensor
Authors: Conteau D. , Bonnet C. , Funfschilling D. , Weber M. , Didierjean S. , Lapicque F. 
Published: May 2010

AbstractSuitable water management is a critical issue to reach the full potential of PEM fuel cells: whereas the membrane must be hydrated enough, liquid droplets formed by water in excess can block the flow in the gas distribution channels and hinder the fuel cell performance. In order to detect the presence of droplets in cathode flow channel, an electrochemical sensor has been developed and tested in a dedicated emulation cell. It is based on the widely used principle of two‐electrode cells for conductivity measurements; the collected signal is converted to impedance values. The sensor, mounted in a gas flow channel grooved in a graphite plate, reacts to the passage of water droplets, either being injected into the continuous air stream or produced by condensation of humidified air at the graphite plate. The time variation of the electrical impedance could be correlated to the observations allowed by the high‐speed digital camera. Water droplets separated from each other by less than a second can be distinguished by the sensor, which is of a sufficient rapidity.
Preparation and Characterisation of Non‐aqueous Proton‐Conducting Membranes with the Low Content of Ionic Liquids
Authors: Baek J.‐S. , Park J.‐S. , Sekhon S. S. , Yang T.‐H. , Shul Y.‐G. , Choi J.‐H. 
Published: May 2010

AbstractIn this study, we prepared ionic liquid based composite membranes applicable for anhydrous and high temperature polymer electrolyte membrane fuel cells (PEMFCs). It is intended to minimise an increase in ionic conductivity of composite membranes by reducing the content of ionic liquids up to 30 wt% along with the addition of acids having the same anions as the ionic liquids. For this purpose, we prepared the composite membrane by solution recasting with 5 wt% Nafion solution, ionic liquids such as 1‐ethyl‐3‐methylimidazolium trifluoro‐methanesulphonate (EMITf) and 1‐ethyl‐3‐methylimidazolium tetrafluoroborate (EMIBF4), and acids such as trifluoromethanesulphonic acid (HTf) and tetra‐fluoroboric acid (HBF4). The composite membranes were characterised by using small‐angle X‐ray scattering (SAXS), thermogravimetric analyser (TGA) and impedance spectroscopy. It was observed that the addition of the acids results in an increase in the proton conductivity of the composite membranes by reducing the viscosity of ionic liquids inside the composite membranes and also by providing additional proton ions due to the dissociation of the acids. In addition, the composite membranes exhibited better thermal stability over 300 °C.
Lanthanum Germanate‐Based Apatites as Electrolyte for SOFCs
Authors: Marrero‐López D. , Díaz‐Carrasco P. , Peña‐Martínez J. , Ruiz‐Morales J. C. , Ramos‐Barrado J. R. 
Published: May 2010

AbstractGermanate apatites with composition La10–xGe5.5Al0.5O26.75–3x/2 have been evaluated for the first time as possible electrolytes for solid oxide fuel cells (SOFCs). Different electrode materials have been considered in this study, i.e. manganite, ferrite, nickelates and cobaltite as cathode materials; and NiO–CGO composite and chromium–manganite as anodes. The chemical compatibility and electrochemical performance of these electrodes with La9.8Ge5.5Al0.5O26.45 have been studied by X‐ray powder diffraction (XRPD) and impedance spectroscopy. The XRPD analysis did not reveal appreciable bulk reactivity with the formation of reaction products between the germanate electrolyte and these electrodes up to 1,200 °C. However, a significant cation interdiffusion was observed by energy dispersive spectroscopy (EDS) at the electrode/electrolyte interface, which leads to a significant decrease of the performance of these electrodes.
N‐Ace: Using solvent accessibility and physicochemical properties to identify protein N‐acetylation sites
Authors: Lee Tzong‐Yi , Hsu Justin Bo‐Kai , Lin Feng‐Mao , Chang Wen‐Chi , Hsu Po‐Chiang , Huang Hsien‐Da 
Published: May 2010

AbstractProtein acetylation, which is catalyzed by acetyltransferases, is a type of post‐translational modification and crucial to numerous essential biological processes, including transcriptional regulation, apoptosis, and cytokine signaling. As the experimental identification of protein acetylation sites is time consuming and laboratory intensive, several computational approaches have been developed for identifying the candidates of experimental validation. In this work, solvent accessibility and the physicochemical properties of proteins are utilized to identify acetylated alanine, glycine, lysine, methionine, serine, and threonine. A two‐stage support vector machine was applied to learn the computational models with combinations of amino acid sequences, and the accessible surface area and physicochemical properties of proteins. The predictive accuracy thus achieved is 5% to 14% higher than that of models trained using only amino acid sequences. Additionally, the substrate specificity of the acetylated site was investigated in detail with reference to the subcellular colocalization of acetyltransferases and acetylated proteins. The proposed method, N‐Ace, is evaluated using independent test sets in various acetylated residues and predictive accuracies of 90% were achieved, indicating that the performance of N‐Ace is comparable with that of other acetylation prediction methods. N‐Ace not only provides a user‐friendly input/output interface but also is a creative method for predicting protein acetylation sites. This novel analytical resource is now freely available at http://N‐Ace.mbc.NCTU.edu.tw/. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2010
Structure‐based quantitative structure‐activity relationship studies of checkpoint kinase 1 inhibitors
Authors: Du Juan , Xi Lili , Lei Beilei , Lu Jing , Li Jiazhong , Liu Huanxiang , Yao Xiaojun 
Published: May 2010

AbstractStructure‐based quantitative structure‐activity relationship (QSAR) studies on a series of checkpoint kinase 1 (Chk1) inhibitors were performed to find the key structural features responsible for their inhibitory activity. Molecular docking was employed to explore the binding mode of all inhibitors at the active site of Chk1 and determine the active conformation for the QSAR studies. Ligand and structure‐based descriptors incorporating the ligand‐receptor interaction were generated based on the docked complex. Genetic Algorithm‐Multiple Linear Regression (GA‐MLR) method was used to build 2D QSAR model. The 2D QSAR model gave a squared correlation coefficient R2 of 0.887, cross‐validated Q2 of 0.837 and the prediction squared correlation coefficient R of 0.849, respectively. Furthermore, three‐dimensional quantitative structure‐activity relationship (3D QSAR) model using comparative molecular field analysis (CoMFA) with R2 of 0.983, Q2 of 0.550 and R of 0.720 was also developed. The obtained results are helpful for the design of novel Chk1 inhibitors with improved activities. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2010
IGFBP‐6 plays a role as an oncosuppressor gene in NPC pathogenesis through regulating EGR‐1 expression
Authors: Kuo Yuan‐Sung , Tang Yueh‐Bih , Lu Tung‐Ying , Wu Han‐Chung , Lin Chin‐Tarng 
Published: May 2010

AbstractNasopharyngeal carcinoma (NPC) is prevalent in south‐eastern Asia, particularly southern China, Singapore and Taiwan. The aim of this study was to identify the pivotal genes that may be altered during NPC progression. Using cDNA microarray analysis, we compared the expression of 18 genes between NPC and normal nasomucosal cells. qRT–PCR analysis found the expression of IBFBP‐6 in NPC cell lines and immunolocalization of IGFBP‐6 in NPC to be very weak. To explore the effects of IGFBP‐6 on NPC tumour growth, we constructed inducible plasmids containing full‐length IGFBP‐6 cDNA (pBIG2i‐IGFBP‐6) and established pBIG2i‐IGFBP‐6‐transfected NPC stable cell lines (NPC‐TW01‐pBIG2i‐IGFBP‐6). We then performed functional analysis of the IGFBP‐6 in cell lines in vitro and in vivo. Over‐expression of IGFBP‐6 significantly suppressed the proliferation, invasion and metastatic activity of NPC cells and increased their apoptosis. We found the EGR‐1, caspase‐1 and TSP‐1 genes to be markedly up‐regulated when NPC‐pBIG2i‐IGFBP‐6 was treated with doxycycline. Knocking down EGR‐1 with EGR‐1 siRNA resulted in a decrease in expression of caspase‐1, TSP‐1 and EGR‐1 but not the expression of IGFBP‐6. However, in knockdown cells the unchanged expression of IGFBP‐6 did not inhibit the migration of NPC cells. Chromatin immunoprecipitation and luciferase reporter assay experiments showed that IGFBP‐6 bound the EGR‐1 promoter regions and activated EGR‐1 promoter. We conclude that IGFBP‐6 can regulate the progression of NPC by regulating the expression of EGR‐1. These results suggest that IGFBP‐6 could be used as a new target in NPC therapy. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Impact of gate dielectric thickness on the electrical properties of AlGaN/GaN MISHFETs on Si(111) substrate
Authors: Eickelkamp Martin , Fahle Dirk , Lindner Johannes , Heuken Michael , Lautensack Christian , Kalisch Holger , Jansen Rolf H. , Vescan Andrei 
Published: May 2010

AbstractWe report on the fabrication and characterization of AlGaN/GaN metal–insulator–semiconductor heterostructure field effect transistors (MISHFETs) using HfO2 and Al2O3 as gate dielectric, deposited by atomic layer deposition (ALD). Improved device performance has been observed for all MISHFET devices as compared to the reference HFET. The additional dielectric layer underneath the gate metallization leads to a significant decrease of gate leakage currents and thus prevents device degradation and losses. Furthermore, the 2DEG sheet carrier concentration increases depending on the k‐value of the oxide as well as the oxide thickness. The thin (3–9 nm) dielectric layer is serving simultaneously as surface passivation, mitigating dc‐to‐rf dispersion. However, less has been reported about the impact of gate insulator thickness on the electrical performance, in particular in terms of dc‐to‐rf dispersion. In this paper, full recovery of dc drain current is demonstrated with a MISHFET with 9 nm Al2O3 oxide thickness.
Integrated fluorescence sensor based on ring‐shaped organic photodiodes
Authors: Lamprecht Bernhard , Abel Tobias , Kraker Elke , Haase Anja , Konrad Christian , Tscherner Martin , Köstler Stefan , Ditlbacher Harald , Mayr Torsten 
Published: May 2010

AbstractWe demonstrate a novel sensor type, which is based on the monolithic integration of luminescent optical sensor spots together with ring‐shaped thin‐film organic photodiodes on one substrate. The organic photodiodes serve as integrated fluorescence detectors, simplifying the detection system by minimizing the number of required optical components. The proposed concept enables filter‐less discrimination between excitation light and generated fluorescence light. The functionality of the concept is demonstrated by an integrated oxygen sensor, exhibiting excellent performance. The sensor spots are excited by an assembled organic light emitting diode. The integrated optical sensor platform is suitable for the parallel detection of multiple parameters. Sensor schemes for the analytical parameters carbon dioxide, temperature and ammonia, are proposed.magnified image(© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Trial design issues and treatment effect modeling in multi‐regional schizophrenia trials
Authors: Chen Yeh‐Fong , Wang Sue‐Jane , Khin Ni A. , Hung H. M. James , Laughren Thomas P. 
Published: May 2010

AbstractIn recent years, we have seen an increasing trend of foreign data as part of clinical trial data submitted in new drug applications (NDA) to US Food and Drug Administration (FDA). To understand the design and analysis characteristics, we studied schizophrenia multi‐regional clinical trials (MRCTs). The schizophrenia data set consisted of a total of 12 585 patients collected from 33 clinical trials with 63.8% patients from North America, the largest region. The data set constituted 10 schizophrenia drug programs in support of NDAs submitted to FDA from December 1993 to December 2005.Two main objectives were pursued. First, we investigated some study design issues including potential heterogeneity of treatment effect via meta analysis and placebo response pattern over time. Second, we performed empirical modeling in two ways, supervised and unsupervised, to explain potential impact of baseline covariates on treatment effect in MRCTs.Based on our analysis results, placebo response appeared to increase over time and primarily attributed to US region. On average, the observed treatment effect in the US was generally smaller than non‐US region. Both supervised and unsupervised empirical modeling selected baseline Positive and Negative Syndrome Scale total score as one of the most important covariates explaining a treatment effect. Region also played a role in explaining potential treatment effect heterogeneity. When baseline body weight was considered as a covariate in an empiric model, our results indicated that it alone did not seem to be an important factor in explaining regional difference. Published in 2010 by John Wiley & Sons, Ltd.
Safety in Surgery: Is Selection the Missing Link?
Authors: Paice Alistair G. , Aggarwal Rajesh , Darzi Ara 
Published: May 2010

AbstractHealth care providers comprise an example of a “high risk organization.” Safety failings within these organizations have the potential to cause significant public harm. Significant safety improvements in other high risk organizations such as the aviation industry have led to the concept of a high reliability organization (HRO)—a high risk organization that has enjoyed a prolonged safety record. A strong organizational culture is common to all successful HROs, encompassing powerful systems of selection and training. Aircrew selection processes provide a good example of this and are examined in detail in this article using the Royal Air Force process as an example. If the lessons of successful HROs are to be applied to health care organizations, candidate selection to specialties such as surgery must become more objective and robust. Other HROs can provide valuable lessons in how this may be approached.
Les urgences urologiques au centre hospitalier national de Nouakchott : aspects épidémiologiques, cliniques et thérapeutiques
Authors: Tfeil Y. Ould , Elmoctar C.A. Ould , Ca M.O. , Jdoud C. Ould 
Published: May 2010

Résumé

But
Présenter les aspects épidémiologiques, cliniques et thérapeutiques des urgences urologiques en milieu africain.

Matériel et methods
Nous avons réalisé une étude rétrospective sur une période de cinq ans colligeant toutes les urgences urologiques reçues par l’équipe de garde au service d’urologie du centre hospitalier national de Nouakchott.

Résultats
Nous avons enregistré 1 200 patients. L’âge moyen de nos patients était de 58,8 ans (un mois à 94 ans). Ces patients avaient un âge supérieur ou égal à 60 ans dans 50,7 % des cas. Le rapport selon le sexe (M/F) était de 20,32. Les affections les plus fréquentes étaient la rétention aiguë d’urine (53 %) et les infections urogénitales qui représentaient dans leur ensemble 16,8 % des cas. Les gangrènes des organes génitaux externes représentaient 4,3 % des urgences et le priapisme 1,8 %. En urgence, 300 interventions chirurgicales ont été effectuées. Les principaux gestes réalisés étaient la pose d’un cystocathétérismesus-pubien(59,7 %) et le débridement d’une gangrène des organes génitaux externes + cystostomie de dérivation (16 %).

Conclusions
L’urgence urologique la plus fréquente dans notre pays était la rétention aiguë d’urine. Certaines pathologies graves, comme la gangrène des organes génitaux externes et le priapisme, n’y sont pas rares.
An empirical comparative evaluation of requirements engineering methods
Authors: España Sergio , Condori-Fernandez Nelly , González Arturo , Pastor Óscar 
Published: May 2010

Abstract
Requirements Engineering (RE) is a relatively young discipline, and still many advances have been achieved during the last decades. In particular, numerous RE approaches are proposed in the literature with the aim of understanding a certain problem (e.g. information systems development) and establishing a knowledge base that is shared between domain experts and developers (i.e. a requirements specification). However, there is a growing concern for empirical validations that assess RE proposals and statements. This paper is related to the assessment of the quality of functional requirements specifications, using the Method Evaluation Model (MEM) as a theoretical framework. The MEM distinguishes the actual efficacy and the perceived efficacy of a method. In order to assess the actual efficacy or RE methods, the conceptual model quality framework by Lindland et al. can be applied; in this paper, we focus on the completeness and granularity of requirements models and extend this framework by defining four new metrics (e.g. degree of functional encapsulations completeness with respect to a reference model, number of functional fragmentation errors). In order to assess the perceived efficacy, conventional questionnaires can be used. A laboratory experiment with master students has been carried out, in order to compare (using the proposed metrics) two RE methods; namely, Use Cases and Communication Analysis. With respect to actual efficacy, results indicate greater model quality (in terms of completeness and granularity) when Communication Analysis guidelines are followed. With respect to perceived efficacy, we found that Use Cases was perceived to be slightly easier to use than Communication Analysis. However, Communication Analysis was perceived to be more useful in terms of determining the proper business processes granularity. The paper discusses these results and highlights some key issues for future research in this area.
On the benefits of quantification in AspectJ systems
Authors: Valente Marco Tulio , Couto Cesar , Faria Jaqueline , Soares Sérgio 
Published: May 2010

AbstractIn this paper, we argue that the most favorable uses of aspects happen when their code relies extensively on quantified statements, i.e., statements that may affect many parts of a system. When this happens, aspects better contribute to separation of concerns, since the otherwise duplicated and tangled code related to the implementation of a crosscutting concern is confined in a single block of code. We provide in the paper both qualitative and quantitative arguments in favor of quantification. We also propose two new metrics to capture in a simple way the amount of quantification employed in the aspects of a given system. Finally, we describe an Eclipse plugin, called ConcernMetrics that estimates the proposed metrics directly from the object-oriented code of an existing system, i.e., before crosscutting concerns are extracted to aspects. Our main motivation is to help developers and maintainers to decide in a cost-effective way if it is worthwhile to use aspects in their systems.
Prevalence of newly diagnosed endometriosis in women attending the general practitioner
Authors: Ferrero Simone , Arena Elisa , Morando Amatore , Remorgida Valentino 
Published: May 2010

AbstractObjectiveTo investigate the prevalence of newly diagnosed endometriosis in premenopausal women who requested a consultation with their general practitioner because of non‐gynecological problems.MethodParticipants in the study were invited to complete a questionnaire investigating the presence of pain symptoms and infertility. On the basis of the characteristics of these symptoms, some patients underwent gynecological examination and transvaginal ultrasound. Radiological examinations were performed when bowel or bladder endometriosis were suspected.ResultsA total of 1291 women without a previous diagnosis of endometriosis were included in the study. On the basis of the symptoms, 108 women were referred to a gynecologist. After gynecological examination and transvaginal ultrasound, endometriosis was suspected in 51 women (47.2%). The diagnosis of endometriosis was confirmed by radiological investigations and/or surgery in 46 patients; the diagnosis of endometriosis was presumed in 2 other women but it was not confirmed by radiological investigations and/or surgery. The prevalence of endometriosis diagnosed by magnetic resonance imaging and/or surgery was 3.6% (46/1291).ConclusionThe prevalence of newly diagnosed symptomatic endometriosis in this study was at least 3.6%. A simple evaluation of symptoms (pain and infertility) that can be performed by a general practitioner facilitates the diagnosis of endometriosis.
Methylenetetrahydrofolate reductase C677T gene mutation as risk factor for sudden sensorineural hearing loss: association with plasma homocysteine, folate and cholesterol concentrations
Authors: Lee E J , Cho Y J , Yoon Y J 
Published: May 2010

AbstractObjective:Impaired cochlear perfusion appears to be the most important event in the development of sudden sensorineural hearing loss. Methylenetetrahydrofolate reductase gene mutations at nucleotide 677 cause reduced methylenetetrahydrofolate reductase enzyme activity, resulting in vascular impairment.Methods:Thirty-three patients and 68 control subjects underwent audiological and haematological investigation.Results:No statistically significant association was found between sudden sensorineural hearing loss and the methylenetetrahydrofolate reductase C677T gene mutation. Mean homocysteine and cholesterol concentrations were significantly higher in patients than in controls. Mean folate levels were significantly lower in patients than in controls. Amongst patients with sudden sensorineural hearing loss, no significant differences in mean cholesterol, homocysteine or folate concentration were found, comparing patients with methylenetetrahydrofolate reductase C677T mutation genotypes with those without.Conclusion:No statistically significant association was found between the methylenetetrahydrofolate reductase C677T gene mutation and sudden sensorineural hearing loss. There was a statistically significant difference between the homocysteine, folate and cholesterol concentrations of sudden sensorineural hearing loss patients, compared with controls. However, there was no statistically significant difference in these levels, comparing patients with and without the methylenetetrahydrofolate reductase C677T mutation.
Dysphonia secondary to traumatic avulsion of the vocal fold in infants
Authors: Bray D , Cavalli L , Eze N , Mills N , Hartley B E J 
Published: May 2010

AbstractObjective:Airway compromise due to paediatric intubation injuries is well documented; however, intubation injuries may also cause severe voice disorders. We report our experience and review the world literature on the voice effects of traumatic paediatric intubation.Case series:We report five cases of children referred to Great Ormond Street Hospital for Children who suffered traumatic avulsion of the vocal fold at the time of, or secondary to, endotracheal intubation. All children had significant dysphonia and underwent specialist voice therapy.Conclusions:The mechanisms of injury, risk factors and management of the condition are discussed. Children suffering traumatic intubation require follow up throughout childhood and beyond puberty as their vocal needs and abilities change. At the time of writing, none of the reported patients had yet undergone reconstructive or medialisation surgery. However, regular specialist voice therapy evaluation is recommended for such patients, with consideration of phonosurgical techniques including injection laryngoplasty or thyroplasty.