bluuebunny/crossref_metadata_2025 huggingface dataset:
Rate of change in early Huntington's disease: A clinicometric analysis
Authors: Meyer Christina , Landwehrmeyer Bernhard , Schwenke Carsten , Doble Adam , Orth Michael , Ludolph Albert C. ,   on behalf of the EHDI Study Group
Published: November 2011

Sensitive outcome measures for patients with Huntington's disease (HD) are required for future clinical trials. Longitudinal data were collected from a 3‐year study of 379 patients suffering from early HD who were not treated by antipsychotics. Progression of UHDRS item scores was evaluated by linear regression and slope, whereas correlation coefficient, standard error, and P values were estimated on the basis of the data of eight evaluations from screening to study end (36 months). For the functional assessment dimension, the proportion of “no” responses at baseline and at study end was determined. Linear progression was observed for the motor score and for all three functional measures (i.e., functional assessment score, independence assessment score, and total functional capacity score). In contrast, there was little evidence for progression of the behavioral assessment score over the study period, whereas the cognitive assessment score was intermediate. Twenty‐two motor‐score items showed linear progression, with a slope of >0.003. These included all chorea items, finger tapping and pronation/supination (left and right), gait, tongue protrusion, and tandem walking. Different symptom domains and individual items evolved at different rates in this group of patients suffering from early HD. It may be possible to select sensitive items to create a simplified version of the UHDRS, which would be more efficient and more sensitive for the assessment of disease progression in clinical trials and natural history studies. © 2011 Movement Disorder Society
Project VALOR: design and methods of a longitudinal registry of post‐traumatic stress disorder (PTSD) in combat‐exposed Veterans in the Afghanistan and Iraqi military theaters of operations
Authors: Rosen Raymond C. , Marx Brian P. , Maserejian Nancy N. , Holowka Darren W. , Gates Margaret A. , Sleeper Lynn A. , Vasterling Jennifer J. , Kang Han K. , Keane Terence M.
Published: November 2011

Few studies have investigated the natural history of post‐traumatic stress disorder (PTSD). Project VALOR (Veterans' After‐discharge Longitudinal Registry) was designed as a longitudinal patient registry assessing the course of combat‐related PTSD among 1600 male and female Veterans who served in Operation Enduring Freedom (OEF) in Afghanistan or Operation Iraqi Freedom (OIF). Aims of the study include investigating patterns and predictors of progression or remission of PTSD and treatment utilization. The study design was based on recommendations from the Agency for Healthcare Quality and Research for longitudinal disease registries and used a pre‐specified theoretical model to select the measurement domains for data collection and interpretation of forthcoming results. The registry will include 1200 male and female Veterans with a recent diagnosis of PTSD in the Department of Veteran Affairs (VA) electronic medical record and a comparison group of 400 Veterans without a medical record‐based PTSD diagnosis, to also allow for case‐control analyses. Data are collected from administrative databases, electronic medical records, a self‐administered questionnaire, and a semi‐structured diagnostic telephone interview. Project VALOR is a unique and timely registry study that will evaluate the clinical course of PTSD, psychosocial correlates, and health outcomes in a carefully selected cohort of returning OEF/OIF Veterans. Copyright © 2011 John Wiley & Sons, Ltd.
TLC Bioautographic Method for Detecting Lipase Inhibitors
Authors: Hassan Abdel Moniem Sadek
Published: November 2011

Introduction

Bioautographic assays using TLC play an important role in the search for active compounds from plants. A TLC bioautographic assay has previously been established for the detection of acetylcholinesterase inhibitors but not for lipases.

Objective

Development of a TLC bioautographic method for detecting lipase inhibitors in plant extracts.

Methodology

After migration of the plant extracts, the TLC plate was sprayed with α‐naphtyl acetate and enzyme solutions before incubation at 37°C for 20 min. Finally, the solution of Fast Blue B salt was sprayed onto the TLC plate giving a purple background colouration.

Results

Lipase inhibitors were visualised as white spots on the TLC plates. Orlistat (a known lipase inhibitor) inhibited lipase down to 0.01 µg. Methanolic extracts of Camellia sinensis (L.) kuntz and Rosmarinus officinalis L after migration on TLC gave enzymatic inhibition when applied in amounts of 82 and 56 µg, respectively. On the other hand the methanolic extract of Morus alba leaves did not exhibit any lipase inhibitory activity.

Conclusion

The screening test was able to detect lipase inhibition by pure reference substances and by compounds present in complex matrices, such as plant extracts. Copyright © 2011 John Wiley & Sons, Ltd.
Growth of Cu(In,Ga)Se2 thin films by a novel single‐stage route based on pulsed electron deposition
Authors: Rampino S. , Bissoli F. , Gilioli E. , Pattini F.
Published: November 2011

We report a novel route for growing Cu(In,Ga)Se2 (CIGS) thin films, based upon the Pulsed Electron Deposition (PED) technique. Unlike other well‐known deposition techniques, PED process allows the stoichiometric deposition of CIGS layers in a single stage, without requiring any further treatments for Cu/(In + Ga) ratio adjustment nor selenization. The structural properties of polycrystalline CIGS films strongly depend on the growth temperature, whereas post‐deposition annealing enhances the grain size and the <112> out‐of‐plane preferred orientation of the chalcopyrite structure, without affecting the film composition. Preliminary measurements of the performances of solar cells based on these films confirm the great potentiality of PED‐grown CIGS as absorber layers. Copyright © 2011 John Wiley & Sons, Ltd.
Proper calibration of ultrasonic power enabled the quantitative analysis of the ultrasonication‐induced amyloid formation process
Authors: Yamaguchi Kei‐ichi , Matsumoto Tomoharu , Kuwata Kazuo
Published: November 2011

To elucidate the mechanisms of ultrasonication on the amyloid fibril formation, we quantitatively determined the ultrasonic power using both calorimetry and potassium iodide (KI) oxidation, and under the properly calibrated ultrasonic power, we investigated the ultasonication‐induced amyloid formation process of the mouse prion protein (mPrP(23–231)). These methods revealed that the ultrasonic power in our system ranged from 0.3 to 2.7 W but entirely dependent on the positions of the ultrasonic stage. Intriguingly, the nucleation time of the amyloid fibrils was found to be shortened almost proportionally to the ultrasonic power, indicating that the probability of the occurrence of nucleus formation increases proportionally to the ultrasonic power. Moreover, mPrP(23–231) formed two types of aggregates: rigid fibrils and short fibrils with disordered aggregates, depending on the ultrasonic power. The nucleation of rigid fibrils required an ultrasonic power larger than 1.5 W. While at the strong ultrasonic power larger than 2.6 W, amyloid fibrils were formed early, but simultaneously fine fragmentation of fibrils occurred. Thus, an ultrasonic power of approximately 2.0 W would be suitable for the formation of rigid mPrP(23–231) fibrils under the conditions utilized (ultrasonication applied for 30 s every 9 min). As ultrasonication has been widely used to amplify the scrapie form of the prion protein, or other amyloids in vitro, the calorimetry and KI oxidation methods proposed here might help determining the adequate ultrasonic powers necessary to amplify them efficiently.
Triplet exciton transfer mechanism between phosphorescent organic dye molecules
Authors: Steinbacher Frank S. , Krause Ralf , Hunze Arvid , Winnacker Albrecht
Published: November 2011

We fabricate simple, solution processed layers containing two kinds of phosphorescent, organic dyes in a poly(methyl methacrylate) (PMMA) matrix. After optical excitation, the close proximity of the emitter molecules with different triplet energies T1 causes a transfer of excitons from the more highly excited dye to the lower one. Optical characterization by photoluminescence (PL) and time resolved PL (TRPL) measurements leads to qualitative and quantitative investigations of the underlying exciton transfer principle. It can be shown that Dexter transfer is not able to describe the experimentally obtained data while an established model for exciton migration between fluorescent molecules, based on Förster theory, presents a consistent picture. Using this model, experimentally obtained values for the characteristic interaction distance R0 agree well with theoretical predictions by basic Förster theory.
Comparative study on nano‐scale III‐V MOSFETs with various channel materials using quantum‐corrected Monte Carlo simulation
Authors: Homma Takahiro , Hasegawa Kei , Watanabe Hisanao , Hara Shinsuke , Fujishiro Hiroki I.
Published: November 2011

We investigate the ability of the nano‐scale III‐V MOSFETs with InGaAs, GaAs or InP channels by using the quantum‐corrected Monte Carlo (MC) simulation. The InGaAs channel shows the largest average electron velocity at the bottleneck, vs, because of the smallest electron effective mass, m * in the Γ valley. However, it is degraded by the electron rebound from the drain through the accumulation in the L valleys, when the gate voltage, Vgs, is highly biased. The electron rebound is more pronounced in the GaAs channel, because of the narrow Γ ‐ L valley separation. Meanwhile, the InP channel shows the smallest vs because of the largest m * in the Γ valley. However, the electron rebound is less pronounced, because of the smaller accumulation in the L valleys. On the other hand, the electron density at the potential bottleneck, nb, is largest in the InP channel, because of the largest gate capacitance owing to the highest density of states, DOS. Eventually, the InP channel shows the largest drain current, Ids (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
31 GHz power characteristics of GaN HEMTs with slightly etched AlGaN layer at ohmic contact
Authors: Hirose Mayumi , Takada Yoshiharu , Matsushita Keiichi , Takagi Kazutaka , Tsuda Kunio
Published: November 2011

Slight etching of an AlGaN layer at ohmic contact was investigated to reduce contact resistance in AlGaN/GaN HEMTs in Ka‐band operation. In the etching process, etched depth was precisely controlled by ICP‐RIE system with a mixture of BCl3 and Cl2 gases. The relation between ohmic contact resistance and etched depth was examined to determine the optimum depth. It was found that a resistance at an etched depth of 5 nm was reduced to 44% of that in the case of the conventional process. This process was applied to fabrication of GaN HEMTs with a gate length of 0.2 μm, and Ka‐band power characteristics were measured. The linear gain of the device was 11.4 dB, the maximum power‐added efficiency was 45%, and the output power density was 5.1 W/mm, under the conditions of a frequency of 31 GHz, a drain bias of 24 V, and a class‐AB operation. The values are higher than those in the case of the conventional process by 0.5 dB for the linear gain, 2 points for the power‐added efficiency, and 11% for the output power. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Radiative transfer over resolved topographic features for high‐resolution weather prediction
Authors: Manners J. , Vosper S. B. , Roberts N.
Published: November 2011

Regional numerical weather prediction models are now routinely run at near kilometre‐scale resolutions where surface features are well resolved and mean grid‐box slopes are highly significant. The resolved topography has an important effect on the radiative transfer at the surface which is not generally represented using fast two‐stream radiation codes. This paper presents a parametrisation of surface radiative transfer for resolved topography suitable for use with a two‐stream code. For the short‐wave bands, the first‐order effects are the interaction of direct solar radiation with surface slopes and shading by surrounding terrain. In the infrared (long‐wave bands), the first‐order effect is the transfer of radiation between visible points on the terrain making use of the sky‐view factor for a sloping surface and the enhanced area of the slope. Energy is conserved over an extended region where the mean flux into the surface will be independent of resolution. These effects are included in the radiation scheme of the Met Office Unified Model and case‐studies are run over the UK using horizontal grid resolutions from 100 m to 1.5 km. The scheme adds fine detail to the forecast which is shown to have a significant impact on forecast skill. Under clear‐sky conditions, short‐wave surface effects can lead to temperature differences of up to 2.5 K, and long‐wave effects to differences of up to 1 K. The magnitude of these effects are expected to be much greater for more complex terrain. A consistent extension to the scheme is outlined to take account of second‐order effects using short‐wave diffuse albedo and long‐wave surface emissivity. These lead to a net change in the surface flux due to multiple surface reflections and should be considered in conjunction with a treatment of sub‐grid terrain complexity. Copyright © 2011 British Crown copyright, the Met Office. Published by John Wiley & Sons Ltd.
Liquid extraction surface analysis mass spectrometry (LESA‐MS) as a novel profiling tool for drug distribution and metabolism analysis: the terfenadine example
Authors: Eikel Daniel , Vavrek Marissa , Smith Sheri , Bason Carol , Yeh Suzie , Korfmacher Walter A. , Henion Jack D.
Published: November 2011

Liquid extraction surface analysis mass spectrometry (LESA‐MS) is a novel surface profiling technique that combines micro‐liquid extraction from a solid surface with nano‐electrospray mass spectrometry. One potential application is the examination of the distribution of drugs and their metabolites by analyzing ex vivo tissue sections, an area where quantitative whole body autoradiography (QWBA) is traditionally employed. However, QWBA relies on the use of radiolabeled drugs and is limited to total radioactivity measured whereas LESA‐MS can provide drug‐ and metabolite‐specific distribution information. Here, we evaluate LESA‐MS, examining the distribution and biotransformation of unlabeled terfenadine in mice and compare our findings to QWBA, whole tissue LC/MS/MS and MALDI‐MSI. The spatial resolution of LESA‐MS can be optimized to ca. 1 mm on tissues such as brain, liver and kidney, also enabling drug profiling within a single organ. LESA‐MS can readily identify the biotransformation of terfenadine to its major, active metabolite fexofenadine. Relative quantification can confirm the rapid absorption of terfendine after oral dosage, its extensive first pass metabolism and the distribution of both compounds into systemic tissues such as muscle, spleen and kidney. The elimination appears to be consistent with biliary excretion and only trace levels of fexofenadine could be confirmed in brain. We found LESA‐MS to be more informative in terms of drug distribution than a comparable MALDI‐MS imaging study, likely due to its favorable overall sensitivity due to the larger surface area sampled. LESA‐MS appears to be a useful new profiling tool for examining the distribution of drugs and their metabolites in tissue sections. Copyright © 2011 John Wiley & Sons, Ltd.
SmartGuard: An autonomous robotic system for inspecting substation equipment
Authors: Wang Binhai , Guo Rui , Li Bingqiang , Han Lei , Sun Yong , Wang Mingrui
Published: November 2011

Substation equipment inspection is necessary for the power industry. With the dramatic increase in the number of substations, unmanned substations are required by the industry. This paper presents SmartGuard, a completely autonomous robotic system that can inspect substation equipment. SmartGuard consists of a robot and a data center. The robot can patrol in a substation and inspect equipment with a visible‐light camera and an infrared thermograph. The acquired images and temperature information are analyzed by the data center. The data center can fuse infrared and visible‐light images and find abnormal hot spots and abnormal appearance. There are 13 SmartGuards currently serving 12 substations, some of which have been working for more than 2 years. The feedback from the field shows that SmartGuard significantly improves the efficiency and reliability of substation inspection. © 2011 Wiley Periodicals, Inc.
Comparison of alternative models for linking drug exposure with adverse effects
Authors: Abrahamowicz Michal , Beauchamp Marie‐Eve , Sylvestre Marie‐Pierre
Published: November 2011

Pharmacoepidemiology investigates associations between time‐varying medication use/dose and risk of adverse events. Applied research typically relies on a priori chosen simple conventional models, such as current dose or any use in the past 3 months. However, different models imply different risk predictions, and only one model can be etiologically correct in any specific applications. We first formally defined several candidate models mapping the time vector of past drug doses (X (t), t  =  1, … ,u) into the value of a time‐varying exposure metric M(u) at current time u. In addition to conventional one‐parameter models, we considered two‐parameter models accounting for recent dose increase or withdrawal and a flexible spline‐based weighted cumulative exposure (WCE) model that defines M(u) as the weighted sum of past doses. In simulations, we generated event times assuming one of the models was correct and then analyzed the data with all candidate models. We demonstrated that the minimum AIC criterion is able to identify the correct model as the best‐fitting model or one of the equivalent (within 4 AIC points of the minimum) models in a vast majority of simulated samples, especially with 500 or more events. We also showed how relying on an incorrect a priori chosen model may largely reduce the power to test for an association. Finally, we demonstrated how the flexible WCE estimates may help with model diagnostics even if the correct model is not WCE. We illustrated the practical advantages of AIC‐based a posteriori model selection and WCE modeling in a real‐life pharmacoepidemiology example. Copyright © 2011 John Wiley & Sons, Ltd.
Outcome‐dependent sampling for longitudinal binary response data based on a time‐varying auxiliary variable
Authors: Schildcrout Jonathan S. , Mumford Sunni L. , Chen Zhen , Heagerty Patrick J. , Rathouz Paul J.
Published: November 2011

Outcome‐dependent sampling (ODS) study designs are commonly implemented with rare diseases or when prospective studies are infeasible. In longitudinal data settings, when a repeatedly measured binary response is rare, an ODS design can be highly efficient for maximizing statistical information subject to resource limitations that prohibit covariate ascertainment of all observations. This manuscript details an ODS design where individual observations are sampled with probabilities determined by an inexpensive, time‐varying auxiliary variable that is related but is not equal to the response. With the goal of validly estimating marginal model parameters based on the resulting biased sample, we propose a semi‐parametric,sequential offsetted logistic regressions(SOLR) approach. The SOLR strategy first estimates the relationship between the auxiliary variable and the response and covariate data by using an offsetted logistic regression analysis where the offset is used to adjust for the biased design. Results from the auxiliary variable model are then combined with the known or estimated sampling probabilities to formulate a second offset that is used to correct for the biased design in the ultimate target model relating the longitudinal binary response to covariates. Because the target model offset is estimated with SOLR, we detail asymptotic standard error estimates that account for uncertainty associated with the auxiliary variable model. Motivated by an analysis of the BioCycle Study (Gaskins et al., Effect of daily fiber intake on reproductive function: the BioCycle Study.American Journal of Clinical Nutrition2009; 90(4): 1061–1069) that aims to describe the relationship between reproductive health (determined by luteinizing hormone levels) and fiber consumption, we examine properties of SOLR estimators and compare them with other common approaches. Copyright © 2011 John Wiley & Sons, Ltd.
Dunnett‐type inference in the frailty Cox model with covariates
Authors: Herberich Esther , Hothorn Torsten
Published: November 2011

A frequent objective in medical research is the investigation of differences in patient survival between several experimental treatments and one standard treatment. In order to assess these differences statistically, we have to apply adjustments for multiple comparisons to prevent an increased number of false‐positive findings. The most prominent procedure of this type is the Bonferroni correction, which maintains the error level but leads to conservative results. On the basis of a general statistical framework for simultaneous inference, we propose a new statistical procedure for many‐to‐one comparisons of treatments with adjustment for covariates for clustered survival data modeled by a frailty Cox model. In contrast to the Bonferroni method, dependencies between estimated effects are taken into account. The resulting simultaneous confidence intervals for the hazard ratios of the experimental treatments compared with a control can be interpreted in terms of both statistical significance and clinical importance. The quality of the new procedure is judged by the coverage probability for the simultaneous confidence intervals. Simulation results show an acceptable performance in balanced and various unbalanced designs. The practical merits are demonstrated by a reanalysis of a chronic myelogeneous leukemia clinical trial. The procedure presented here works well for multiple comparisons with a control with adjustment for covariates for survival data from multicenter clinical trials. Copyright © 2011 John Wiley & Sons, Ltd.
Multihomed SIP‐based network mobility for the scheduled public transit service
Authors: Lee Chao‐Hsien , Huang Chung‐Ming , Tseng Po‐Han
Published: November 2011

Network mobility (NEMO) enables a group of nodes to connect to the back‐end infrastructure during the movement. Because a vehicle must provide passengers good enough transmission quality, various access techniques, for example, 3 G/3.5 G, Wi‐Fi or dedicated short range communication, can be simultaneously equipped to aggregate bandwidth and tolerate link failure. This paper extends the Session Initiation Protocol (SIP)‐based NEMO framework to support multihoming. First, IEEE 802.21 Media Independent Handover (MIH) is integrated to manage multiple egress interfaces in an on‐board unit (OBU). Second, a dynamic synchronization mechanism using the SIP SUBSCRIBE and NOTIFY methods is proposed to manage multiple OBUs in a vehicle. Furthermore, the framework is applied to public transportation systems, for example, bus, train, or mass rapid transit. Passengers may need to transit several times during their journeys. The transit behavior must induce a flood of signaling messages for location update. In this paper, the SIP REFER method is exploited to reduce signaling messages while a group of passengers have scheduled their transit in advance. Copyright © 2011 John Wiley & Sons, Ltd.
Genetic variation of pre‐mRNA alternative splicing in human populations
Authors: Lu Zhi‐Xiang , Jiang Peng , Xing Yi
Published: November 2011

The precise splicing outcome of a transcribed gene is controlled by complex interactions between cis regulatory splicing signals and trans‐acting regulators. In higher eukaryotes, alternative splicing is a prevalent mechanism for generating transcriptome and proteome diversity. Alternative splicing can modulate gene function, affect organismal phenotype and cause disease. Common genetic variation that affects splicing regulation can lead to differences in alternative splicing between human individuals and consequently impact expression level or protein function. In several well‐documented examples, such natural variation of alternative splicing has indeed been shown to influence disease susceptibility and drug response. With new microarray and sequencing‐based genomic technologies that can analyze eukaryotic transcriptomes at the exon or nucleotide level, it has become possible to globally compare the alternative splicing profiles across human individuals in any tissue or cell type of interest. Recent large‐scale transcriptome studies using high‐density splicing‐sensitive microarray and deep RNA sequencing (RNA‐Seq) have revealed widespread genetic variation of alternative splicing in humans. In the future, an extensive catalog of alternative splicing variation in human populations will help elucidate the molecular underpinnings of complex traits and human diseases, and shed light on the mechanisms of splicing regulation in human cells. WIREs RNA 2012, 3:581–592. doi: 10.1002/wrna.120

This article is categorized under:

RNA Evolution and Genomics > Computational Analyses of RNA

RNA Processing > Splicing Regulation/Alternative Splicing

RNA in Disease and Development > RNA in Disease
Cancellous Bone Graft and Kirschner Wire Fixation as a Treatment for Cavitary-Type Scaphoid Nonunions Exhibiting DISI
Authors: Kirkham Stuart G. , Millar Michael J.
Published: November 2011

Background

Cavitary-type scaphoid non-unions represent one of the most difficult treatment challenges amongst all scaphoid non-unions as they exhibit bone loss, scaphoid shortening, flexion (‘humpback’) deformity and dorsal intercalated segmental instability (DISI), creating altered carpal mechanics which may proceed to the degenerative changes of scapholunate advanced collapse of the wrist. Our technique and its rationale are presented in the largest-to-date series on cavitary scaphoid non-unions exhibiting DISI.

Methods

Our technique for treatment of these cavitary nonunions is presented through a series of 27 patients. Results Union was achieved in (26/27) 96% of cases, with no complications. Carpal mechanics was restored, with an average carpal height index of 1.52±0.06, and an average scapholunate angle was 46±9°. Average follow-up was 2.2 years.

Conclusion

In this subset of patients, we believe this technique is less technically demanding than the use of either cortico-cancellous grafts or various compression screws. Our success equals or betters that of other published techniques, with all patients enjoying a full return to work, even in occupations demanding heavy labour. We believe that scaphoid union, coupled with the often difficult restoration of carpal height and intra-carpal angles, has produced very good functional outcomes in the management of these challenging cases.
Olfactomedin-4 is a glycoprotein secreted into mucus in active IBD
Authors: Gersemann Michael , Becker Svetlana , Nuding Sabine , Antoni Lena , Ott German , Fritz Peter , Oue Naohide , Yasui Wataru , Wehkamp Jan , Stange Eduard F.
Published: November 2011

Background: Olfactomedin-4 (OLFM4) is a glycoprotein characteristic of intestinal stem cells and apparently involved in mucosal defense of the stomach and colon. Here we studied its expression, regulation and function in IBD.

Methods: The expression of OLFM4, mucins Muc1 and Muc2, the goblet cell differentiation factor Hath1 and the proinflammatory cytokine IL-8 was measured in inflamed or noninflamed colon in IBD patients and controls. OLFM4 protein was located by immunohistochemistry, quantified by Dot Blot and its binding capacity to defensins HBD1-3 was investigated. The influence of bacteria with or without the Notch blocker dibenzazepine (DBZ) and of several cytokines on OLFM4 expression was determined in LS174T cells.

Results: OLFM4 mRNA and protein were significantly upregulated in inflamed CD (4.3 and 1.7-fold) and even more pronounced in UC (24.8 and 3.7-fold). OLFM4 expression was correlated to IL-8 but not to Hath1. In controls immunostaining was restricted to the lower crypts but in inflamed IBD it expanded up to the epithelial surface including the mucus. OLFM4 bound to HBD1-3 without profoundly inactivating these defensins. In LS174T-cells OLFM4 mRNA was significantly augmented after incubation with Escherichia coli K12, Escherichia coli Nissle and Bacteroides vulgatus. DBZ downregulated OLFM4 expression and blocked bacterial induction whereas IL-22 but not TNF-α was stimulatory.

Conclusions: OLFM4 is overexpressed in active IBD and secreted into mucus. The induction is triggered by bacteria through the Notch pathway and also by the cytokine IL-22. OLFM4 seems to be of functional relevance in IBD as a mucus component, possibly by binding defensins.
THE CHALLENGES OF OFFERING PUBLIC SECOND TRIMESTER ABORTION SERVICES IN SOUTH AFRICA: HEALTH CARE PROVIDERS' PERSPECTIVES
Authors: HARRIES J. , LINCE N. , CONSTANT D. , HARGEY A. , GROSSMAN D.
Published: November 2011

Around 25% of abortions in South Africa are performed in the second trimester. This study aimed to better understand what doctors, nurses and hospital managers involved in second trimester abortion care thought about these services and how they could be improved. Nineteen in-depth interviews with abortion-related service providers and managers in the Western Cape Province, South Africa, were undertaken. Data were analysed using a thematic analysis approach. Participants expressed resistance to the dilation and evacuation (D&E) procedure, as this required more active provider involvement. Medical abortion was preferred as it required less provider involvement in the abortion process. A shortage of providers willing to perform D&E resulted in most public sector services being outsourced to private sector doctors. Respondents noted an increased demand for services and a concomitant lack of infrastructure, physical space and personnel to respond to these demands, sometimes resulting in fragmented or poor quality care. At medical induction sites, most thought introducing the combined mifepristone–misoprostol regimen would improve service capacity, although they were concerned about cost. Improving contraceptive services was also seen as a much-needed intervention to improve care and prevent abortion. Ongoing training, including values clarification, as well as emotional support and team-building for providers are needed to ensure sustainable, high-quality second trimester abortion services.
Risk Factors for Selective Cognitive Decline in Dialyzed Patients with End-Stage Renal Disease: Evidence from Verbal Fluency Analysis
Authors: Harciarek Michał , Williamson John B. , Biedunkiewicz Bogdan , Lichodziejewska-Niemierko Monika , Dębska-Ślizień Alicja , Rutkowski Bolesław
Published: November 2011

Although dialyzed patients often have cognitive problems, little is known about the nature of these deficits. We hypothesized that, in contrast to semantic fluency relying mainly on temporal lobes, phonemic fluency, preferentially depending on functions of frontal-subcortical systems, would be particularly sensitive to the constellation of physiological pathological processes associated with end-stage renal disease and dialysis. Therefore, we longitudinally compared phonemic and semantic fluency performance between 49 dialyzed patients and 30 controls. Overall, patients performed below controls only on the phonemic fluency task. Furthermore, their performance on this task declined over time, whereas there was no change in semantic fluency. Moreover, this decline was related to the presence of hypertension and higher blood urea nitrogen. We suggest that these findings may be due to a combination of vascular and topic effects that impact more on fronto-subcortical than temporal lobe networks, but this speculation requires direct confirmation. (JINS, 2012,18, 162–167)
Party organizational strength and party unity in post-communist Europe
Authors: Tavits Margit
Published: November 2011

The existing comparative literature focuses on political institutions to explain party unity in parliament, and largely ignores the role of party characteristics in this process. This study argues that the strength of political party organization directly and independently influences the level of party unity. Organizational strength makes the party a valuable asset to individual legislators, thus increasing their willingness to be disciplined. Therefore, parties with strong organizations are likely to be more unified in parliament than those with weak organizations. I find support for this argument with data from four post-communist democracies: the Czech Republic, Estonia, Hungary, and Poland. Narratives suggest that the proposed causal mechanism is plausible.
Expertise in Video Gaming and Driving Skills
Authors: Jäncke Lutz , Klimmt Christoph
Published: November 2011

We assessed whether video game experience exerts substantial influence on standardised measures of driving skill. Three subject groups (n = 90) with different video game experiences (frequent, moderate and without extensive experience) performed standard driving tests on a driving simulator, computerised tests measuring driving skills, and standard attention tests. Even extensive video game experience had no influence on performance in computerised tests measuring driving skills. But there was a strong influence of video game experience on computerised attention tests, with frequent gamers outperforming the control subjects in several attention measures. These findings show that the evaluation of driving skill should rely strongly on driving skills tests which are specifically designed for this particular purpose. The use of standard computerised attention tests for the assessment of driving skills runs the risk of introducing a performance bias during testing attributable to frequent video game use.
On the importance of wave‐like structures in the occurrence of equatorial plasma bubbles: A case study
Authors: Narayanan V. Lakshmi , Taori A. , Patra A. K. , Emperumal K. , Gurubaran S.
Published: November 2011

Coordinated observations of equatorial plasma bubbles (EPBs) have been made with an all‐sky airglow imager, narrow bandwidth photometer, VHF radar, and ionosonde over the Indian sector on the night of 23 March 2009. The prereversal enhancement (PRE) in the vertical plasma drift during the postsunset hours on this day was moderate. Range type spread F was found to occur immediately after the satellite traces were noted in the ionograms. This was well recorded in measurements made by all‐sky imager, narrow band photometer, and VHF radar. The airglow emission intensities also revealed the presence of a large‐scale wave‐like structure (LSWS) together with the plasma bubbles that coincided with plume structures observed in the VHF radar echoes. The periodicity of the occurrence of bubbles (and plumes) and their interdepletion distances suggest the presence of small‐scale wave‐like structures (SSWS) on this night. The results are compared with the ionosonde observations made on the night of 21 February 2008. The PRE and the maximum height attained by the F layer were very similar to that of 23 March 2009. In addition, the ionograms showed the presence of satellite traces. However, no subsequent evolution of spread F was noticed. Considering the satellite traces to have their origin in LSWS, these observations imply that though the presence of LSWS is important for the triggering of EPBs, they alone are not sufficient. However, the coexistence of both LSWS and SSWS may have the potential to trigger EPBs.
Magnetospheric location of the equatorward prebreakup arc
Authors: Sergeev V. , Nishimura Y. , Kubyshkina M. , Angelopoulos V. , Nakamura R. , Singer H.
Published: November 2011

We address the long‐standing problem of the location and origin of the equatorwardmost Pre‐Breakup auroral Arc (PBA) by combining energetic particle observations from NOAA Polar Operational Environmental Satellites (POES) overpasses of prebreakup arcs with auroral imaging and magnetospheric observations from the Time History of Events and Macroscale Interactions during Substorms (THEMIS) mission. The prebreakup arc was observed within a few minutes of auroral breakup and ∼1–2 hours in MLT from the breakup meridian. For three ideal conjunctions out of 16 PBA crossings, we also construct a dynamically‐adapted magnetospheric model after adding concurrent magnetic observations by the GOES spacecraft. Model‐predicted isotropy boundaries of energetic particles are compared with observations, informing us about model uncertainties. Direct mapping with adapted models as well as particle flux comparisons between the ionosphere and the magnetosphere confirm that the PBA source lies within the region of the steep equatorial magnetic field gradient, where the equatorial field is also small (5–20 nT). That equatorial location, at roughly 8–10 Re, is likely the earthwardmost edge of the thin cross‐tail current sheet. From observations we find that the prebreakup arc nearly coincides in latitude with the energy‐dispersed, 30–300 keV electron isotropy boundary. Here the non‐adiabatic electron precipitation from the high flux region of the outer radiation belt near its outer edge produces a narrow, intense energetic electron precipitation region, called the energetic electron arc (EEA). Two fortuitous conjunctions with DMSP also confirm that energetic (>20 keV) EEA electrons and lower energy, inverted‐V electrons associated with the PBA are collocated. We suggest that EEA formation is an inherent part of the PBA formation process. By creating an enhanced conductance strip, the EEA (a seed arc) produces ionospheric polarization that leads to field‐aligned current generation and associated field‐aligned electron precipitation. We also discuss implications of our findings for the substorm onset mechanism.
Modeling clear‐sky solar radiation across a range of elevations in Hawai‘i: Comparing the use of input parameters at different temporal resolutions
Authors: Longman Ryan J. , Giambelluca Thomas W. , Frazier Abby G.
Published: November 2011

Estimates of clear sky global solar irradiance using the parametric model SPCTRAL2 were tested against clear sky radiation observations at four sites in Hawai‘i using daily, mean monthly, and 1 year mean model parameter settings. Atmospheric parameters in SPCTRAL2 and similar models are usually set at site‐specific values and are not varied to represent the effects of fluctuating humidity, aerosol amount and type, or ozone concentration, because time‐dependent atmospheric parameter estimates are not available at most sites of interest. In this study, we sought to determine the added value of using time dependent as opposed to fixed model input parameter settings. At the AERONET site, Mauna Loa Observatory (MLO) on the island of Hawai‘i, where daily measurements of atmospheric optical properties and hourly solar radiation observations are available, use of daily rather than 1 year mean aerosol parameter values reduced mean bias error (MBE) from 18 to 10 W m−2 and root mean square error from 25 to 17 W m−2. At three stations in the HaleNet climate network, located at elevations of 960, 1640, and 2590 m on the island of Maui, where aerosol‐related parameter settings were interpolated from observed values for AERONET sites at MLO (3397 m) and Lāna‘i (20 m), and precipitable water was estimated using radiosonde‐derived humidity profiles from nearby Hilo, the model performed best when using constant 1 year mean parameter values. At HaleNet Station 152, for example, MBE was 18, 10, and 8 W m−2 for daily, monthly, and 1 year mean parameters, respectively.
Heat wave frequency variability over North America: Two distinct leading modes
Authors: Wu Zhiwei , Lin Hai , Li Jianping , Jiang Zhihong , Ma Tingting
Published: November 2011

Seasonal prediction of heat wave variability is a scientific challenge and of practical importance. This study investigates the heat wave frequency (HWF) variability over North America (NA) during the past 53 summers (1958–2010). It is found that the NA HWF is dominated by two distinct modes: the interdecadal (ID) mode and the interannual (IA) mode. The ID mode primarily depicts a HWF increasing pattern over most of the NA continent except some western coastal areas. The IA mode resembles a tripole HWF anomaly pattern with three centers over the northwestern, central, and southern NA. The two leading modes have different dynamic structures and predictability sources. The ID mode is closely associated with the prior spring sea surface temperature anomaly (SSTA) in the tropical Atlantic and tropical western Pacific that can persist throughout the summer, whereas the IA mode is linked to the development of El Niño–Southern Oscillation. A simplified general circulation model is utilized to examine the possible physical mechanism. For the ID mode the tropical Atlantic SSTA can induce a Gill‐type response which extends to NA, while the northwestern Pacific SSTA excites a Rossby wave train propagating eastward toward NA. These two flow patterns jointly contribute to the formation of the large‐scale circulation anomalies associated with the ID mode. For the IA mode the corresponding circulation anomalies are basically similar to a Pacific‐North America pattern. The subsidence associated with high‐pressure anomalies warms and dries the boundary layer, inhibiting cloud formation. The resulting surface radiative heating further warms the surface. For the low‐pressure anomalies the situation is just opposite. Through such processes these SSTAs can exert profound influences on the HWF variability over NA.
Analogous nutrient limitations in unicellular diazotrophs and Prochlorococcus in the South Pacific Ocean
Authors: Moisander Pia H , Zhang Ruifeng , Boyle Edward A , Hewson Ian , Montoya Joseph P , Zehr Jonathan P
Published: November 2011

Growth limitation of phytoplankton and unicellular nitrogen (N2) fixers (diazotrophs) were investigated in the oligotrophic Western South Pacific Ocean. Based on change in abundances of nifH or 23S rRNA gene copies during nutrient-enrichment experiments, the factors limiting net growth of the unicellular diazotrophs UCYN-A (Group A), Crocosphaera watsonii, γ-Proteobacterium 24774A11, and the non-diazotrophic picocyanobacterium Prochlorococcus, varied within the region. At the westernmost stations, numbers were enhanced by organic carbon added as simple sugars, a combination of iron and an organic chelator, or iron added with phosphate. At stations nearest the equator, the nutrient-limiting growth was not apparent. Maximum net growth rates for UCYN-A, C. watsonii and γ-24774A11 were 0.19, 0.61 and 0.52 d−1, respectively, which are the first known empirical growth rates reported for the uncultivated UCYN-A and the γ-24774A11. The addition of N enhanced total phytoplankton biomass up to 5-fold, and the non-N2-fixing Synechococcus was among the groups that responded favorably to N addition. Nitrogen was the major nutrient-limiting phytoplankton biomass in the Western South Pacific Ocean, while availability of organic carbon or iron and organic chelator appear to limit abundances of unicellular diazotrophs. Lack of phytoplankton response to nutrient additions in the Pacific warm pool waters suggests diazotroph growth in this area is controlled by different factors than in the higher latitudes, which may partially explain previously observed variability in community composition in the region.
Magnitude and regulation of bacterioplankton respiratory quotient across freshwater environmental gradients
Authors: Berggren Martin , Lapierre Jean-François , del Giorgio Paul A
Published: November 2011

Bacterioplankton respiration (BR) may represent the largest single sink of organic carbon in the biosphere and constitutes an important driver of atmospheric carbon dioxide (CO2) emissions from freshwaters. Complete understanding of BR is precluded by the fact that most studies need to assume a respiratory quotient (RQ; mole of CO2 produced per mole of O2 consumed) to calculate rates of BR. Many studies have, without clear support, assumed a fixed RQ around 1. Here we present 72 direct measurements of bacterioplankton RQ that we carried out in epilimnetic samples of 52 freshwater sites in Québec (Canada), using O2 and CO2 optic sensors. The RQs tended to converge around 1.2, but showed large variability (s.d.=0.45) and significant correlations with major gradients of ecosystem-level, substrate-level and bacterial community-level characteristics. Experiments with natural bacterioplankton using different single substrates suggested that RQ is intimately linked to the elemental composition of the respired compounds. RQs were on average low in net autotrophic systems, where bacteria likely were utilizing mainly reduced substrates, whereas we found evidence that the dominance of highly oxidized substrates, for example, organic acids formed by photo-chemical processes, led to high RQ in the more heterotrophic systems. Further, we suggest that BR contributes to a substantially larger share of freshwater CO2 emissions than presently believed based on the assumption that RQ is ∼1. Our study demonstrates that bacterioplankton RQ is not only a practical aspect of BR determination, but also a major ecosystem state variable that provides unique information about aquatic ecosystem functioning.
Anaerobic oxidation of methane at different temperature regimes in Guaymas Basin hydrothermal sediments
Authors: Biddle Jennifer F , Cardman Zena , Mendlovitz Howard , Albert Daniel B , Lloyd Karen G , Boetius Antje , Teske Andreas
Published: November 2011

Anaerobic oxidation of methane (AOM) was investigated in hydrothermal sediments of Guaymas Basin based on δ13C signatures of CH4, dissolved inorganic carbon and porewater concentration profiles of CH4 and sulfate. Cool, warm and hot in-situ temperature regimes (15–20 °C, 30–35 °C and 70–95 °C) were selected from hydrothermal locations in Guaymas Basin to compare AOM geochemistry and 16S ribosomal RNA (rRNA), mcrA and dsrAB genes of the microbial communities. 16S rRNA gene clone libraries from the cool and hot AOM cores yielded similar archaeal types such as Miscellaneous Crenarchaeotal Group, Thermoproteales and anaerobic methane-oxidizing archaea (ANME)-1; some of the ANME-1 archaea formed a separate 16S rRNA lineage that at present seems to be limited to Guaymas Basin. Congruent results were obtained by mcrA gene analysis. The warm AOM core, chemically distinct by lower porewater sulfide concentrations, hosted a different archaeal community dominated by the two deep subsurface archaeal lineages Marine Benthic Group D and Marine Benthic Group B, and by members of the Methanosarcinales including ANME-2 archaea. This distinct composition of the methane-cycling archaeal community in the warm AOM core was confirmed by mcrA gene analysis. Functional genes of sulfate-reducing bacteria and archaea, dsrAB, showed more overlap between all cores, regardless of the core temperature. 16S rRNA gene clone libraries with Euryarchaeota-specific primers detected members of the Archaeoglobus clade in the cool and hot cores. A V6-tag high-throughput sequencing survey generally supported the clone library results while providing high-resolution detail on archaeal and bacterial community structure. These results indicate that AOM and the responsible archaeal communities persist over a wide temperature range.