bluuebunny/crossref_metadata_2025_split huggingface dataset:
Water filtration properties of novel composite membranes combining solution electrospinning and needleless melt electrospinning methods
Authors: Li Xiaohu , Yang Weimin , Li Haoyi , Wang Yan , Bubakir Mahmoud M , Ding Yumei , Zhang Youchen 
Published: November 2014

ABSTRACTNew composite polyvinyl alcohol (PVA)/polypropylene (PP) membranes were prepared by combining both solution electrospinning and melt electrospinning methods. Self‐designed and made needleless melt electrospinning device was used to fabricate PP membranes which acted as the support layer. PVA membrane on the surface was fabricated via solution electrospinning. The electrospun PVA/PP composite membranes were characterized by the pore size distribution, pure water flux, and rejection ratio, then compared with general composite membranes. Characterizations revealed that the fiber diameter of solution electrospun PVA membrane and melt electrospun PP membrane were 0.171 ± 0.027 and 2.24 ± 0.33 μm, respectively, and the average pore size was 0.832 μm and 27.29 μm, which was much smaller than the nonwoven membrane. The rejection ratio to the 500 nm particles of the PVA/PP composite membrane could reach more than 96%, which was much larger than that of the PVA/non‐woven substrate of 90%, and the melt electrospun PP membrane of 80%, and still maintained high permeate flux of 32,346 L/m2h under the pressure of 0.24 bar. This approach of compositing the solution electrospun membranes and melt electrospun membranes could be useful in designing novel microfiltration membrane owning both higher flux and higher rejection ratio. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41601.
Development and validation of the Surgical Outcome Risk Tool (SORT)
Authors: Protopapa K L , Simpson J C , Smith N C E , Moonesinghe S R 
Published: November 2014

Abstract

Background
Existing risk stratification tools have limitations and clinical experience suggests they are not used routinely. The aim of this study was to develop and validate a preoperative risk stratification tool to predict 30-day mortality after non-cardiac surgery in adults by analysis of data from the observational National Confidential Enquiry into Patient Outcome and Death (NCEPOD) Knowing the Risk study.

Methods
The data set was split into derivation and validation cohorts. Logistic regression was used to construct a model in the derivation cohort to create the Surgical Outcome Risk Tool (SORT), which was tested in the validation cohort.

Results
Prospective data for 19 097 cases in 326 hospitals were obtained from the NCEPOD study. Following exclusion of 2309, details of 16 788 patients were analysed (derivation cohort 11 219, validation cohort 5569). A model of 45 risk factors was refined on repeated regression analyses to develop a model comprising six variables: American Society of Anesthesiologists Physical Status (ASA-PS) grade, urgency of surgery (expedited, urgent, immediate), high-risk surgical specialty (gastrointestinal, thoracic, vascular), surgical severity (from minor to complex major), cancer and age 65 years or over. In the validation cohort, the SORT was well calibrated and demonstrated better discrimination than the ASA-PS and Surgical Risk Scale; areas under the receiver operating characteristic (ROC) curve were 0·91 (95 per cent c.i. 0·88 to 0·94), 0·87 (0·84 to 0·91) and 0·88 (0·84 to 0·92) respectively (P &lt; 0·001).

Conclusion
The SORT allows rapid and simple data entry of six preoperative variables, and provides a percentage mortality risk for individuals undergoing surgery.
Systematic review and meta-analysis comparing three techniques for pancreatic remnant closure following distal pancreatectomy
Authors: Zhang H , Zhu F , Shen M , Tian R , Shi C J , Wang X , Jiang J X , Hu J , Wang M , Qin R Y 
Published: November 2014

Abstract

Background
Established closure techniques for the pancreatic remnant after distal pancreatectomy include stapler, suture and anastomotic closure. However, controversy remains regarding the ideal technique; therefore, the aim of this study was to compare closure techniques and risk of postoperative pancreatic fistula (POPF).

Methods
A systematic review was carried out according to PRISMA guidelines for studies published before January 2014 that compared at least two closure techniques for the pancreatic remnant in distal pancreatectomy. A random-effects model was constructed using weighted odds ratios (ORs).

Results
Thirty-seven eligible studies matched the inclusion criteria and 5252 patients who underwent distal pancreatectomy were included. The primary outcome measure, the POPF rate, ranged 0 from to 70 per cent. Meta-analysis of the 31 studies comparing stapler versus suture closure showed that the stapler technique had a significantly lower rate of POPF, with a combined OR of 0·77 (95 per cent c.i. 0·61 to 0·98; P = 0·031). Anastomotic closure was associated with a significantly lower POPF rate than suture closure (OR 0·55, 0·31 to 0·98; P = 0·042). Combined stapler and suture closure had significantly lower POPF rates than suture closure alone, but no significant difference compared with stapler closure alone.

Conclusion
The use of stapler closure or anastomotic closure for the pancreatic remnant after distal pancreatectomy significantly reduces POPF rates compared with suture closure. The combination of stapler and suture closure shows superiority over suture closure alone.
A Novel Tyrosine–Heme CO Covalent Linkage in F43Y Myoglobin: A New Post‐translational Modification of Heme Proteins
Authors: Yan Dao‐Jing , Li Wei , Xiang Yu , Wen Ge‐Bo , Lin Ying‐Wu , Tan Xiangshi 
Published: November 2014

AbstractHeme post‐translational modification plays a key role in tuning the structure and function of heme proteins. We herein report a novel tyrosine–heme covalent CO bond in an artificially produced sperm whale myoglobin (Mb) mutant, F43Y Mb, which formed spontaneously in vivo between the Tyr43 hydroxy group and the heme 4‐vinyl group. This highlights the diverse chemistry of heme post‐translational modifications, and lays groundwork for further investigation of the structural and functional diversity of covalently‐bound heme proteins.
A Stochastic Model for Liquid Dispersion in a Trickle‐Bed Reactor
Authors: Liu Peng , Huang Zi‐Bin , Zhu Jun , Yu Kun , Cheng Zhen‐Min 
Published: November 2014

AbstractA stochastic model was developed to describe the liquid radial dispersion in a trickle‐bed reactor, which has conventionally been modeled by the effective diffusion model. To establish the stochastic model, the column was divided into some layers of particles in the axial direction and several annulus rings in each layer in the radial direction. The liquid spreading was regarded as a fluid transport process and the matrix of transfer probability was derived based on the coordinates of the particle network in the cross‐section of the column. With this transfer probability matrix and the initial liquid distribution, the liquid distribution in the downstream was predicted. In order to evaluate the model parameters, experimental data of the liquid dispersion were obtained from electrical capacitance tomography images and tracer injection. Good agreement was obtained between the stochastic model and the experimental liquid distribution data.
Kaltgasspritzen zur Mikrostrukturierung von Bauteiloberflächen
Authors: Schmidt Kilian , Buhl Sebastian , Hund David , Ripperger Siegfried 
Published: November 2014

AbstractEin thermisches Spritzverfahren zur Strukturierung von metallischen Oberflächen mit Mikropartikeln wird vorgestellt. Stickstoff, zusammen mit Titandioxid‐Mikropartikeln, wird komprimiert, erhitzt und über eine angepasste Laval‐Düse auf Titan‐Probeplättchen gesprüht. Theoretische Betrachtungen und CFD‐Simulationen zeigen, dass die auf die Oberfläche auftreffenden Partikel mit dieser fest verbunden werden müssten durch den Effekt des sogenannten Kaltgasspritzens. Die Partikelhaftung auf der Oberfläche wird durch Ultraschallreinigungsversuche quantifiziert.
Katalysatoren des Leuna Werkes: ein Beitrag zur Geschichte der technischen heterogenen Katalyse – Teil I: Die Entwicklungen von 1921 bis 1945
Authors: Becker Karl 
Published: November 2014

AbstractDie Entwicklung und Realisierung der ersten großtechnischen Hochdrucksynthesen, der Ammoniaksynthese, der Methanolsynthese sowie der Synthese von Kohlenwasserstoffen aus Kohle, Teeren und Ölen war der Verdienst der BASF in Ludwigshafen und ab 1917 ihrer Tochter in Leuna. Auf Basis der damit verfügbaren Rohstoffe folgte eine Fülle weiterer Synthesen. Eine entscheidende Rolle haben dabei technische Katalysatoren gespielt. Es wird versucht, die faszinierende Geschichte dieser Katalysatoren bis 1945 nachzuvollziehen.
Filter & hold: a mixed continuous‐/discrete‐time technique for time‐constant scaling
Authors: Tavares Vítor Grade , Duarte Cândido , Guedes de Oliveira Pedro , Príncipe José Carlos 
Published: November 2014

SummaryThe work reported in this paper introduces a periodic switching technique applied to continuous‐time filters, whose outcome is an equivalent filter with scaled time‐constants. The principle behind the method is based on a procedure that extends the integration time by periodically interrupting the normal integration of the filter. The net result is an up scaling of the time constant, inversely proportional to the switching duty‐cycle. This is particularly suitable for reducing the area occupied by passive devices in integrated circuits, as well as to accurately calibrate the filter dynamics. Previous works have been following this concept in an entirely continuous‐time perspective, either focusing on specific circuits or using approximations to provide an extended analysis. This paper includes input/output sampling to derive a closed‐form representation for the scaling technique herein coined as ‘Filter & Hold’ (F&H). A detailed mathematical analysis is described, demonstrating that the F&H concept represents an exact filtering solution. Simulation results and experimental measurements are provided to further validate the theoretical analysis for an F&H vector‐filter prototype. Copyright © 2014 John Wiley & Sons, Ltd.
Regulatory elements retained during chordate evolution: Coming across tunicates
Authors: Vassalli Quirino Attilio , Anishchenko Evgeniya , Caputi Luigi , Sordino Paolo , D'Aniello Salvatore , Locascio Annamaria 
Published: November 2014

SummaryUnderstanding the role of conserved noncoding elements (CNEs) throughout the genome is taking advantage of the improved efficiency of genome‐sequencing techniques and bioinformatics tools. Tunicates diverged before the vertebrate whole genome duplications and, therefore, represent an optimal model system to study the evolution of complex regulatory networks. Here, we review the current knowledge on the characterization of CNEs during embryonic development, focusing on the evolutionary similarity and divergence between tunicates and other chordates. Many vertebrate specific CNEs that regulate developmental processes were identified based on high level of sequence conservation, but only few of them have been recognized in tunicates or other invertebrates because of genomic sequences divergence. We discuss recent studies demonstrating that a combination of different methodologies, based not only on high sequence identity, can collectively be used to identify CNEs with regulatory activity in phylogenetically distant species. Here, a low sequence constraints approach was successfully used to search orthologous chordate gene regions for cross‐species conserved regulatory elements that control developmental genes. genesis 53:66–81, 2015. © 2014 Wiley Periodicals, Inc.
Ammonium‐Salt‐Tagged IMesAuCl Complexes and Their Application in Gold‐Catalyzed Cycloisomerization Reactions in Water
Authors: Belger Katrin , Krause Norbert 
Published: November 2014

AbstractThe total synthesis and characterization of ammonium‐salt‐tagged IMesAuCl complexes is described. Moreover, we have demonstrated their catalytic activity and recyclability in cycloisomerization reactions of allenic and acetylenic alcohols in water. The water‐soluble gold catalysts can be stabilized by the addition of LiCl.
Combined hillslope diffusion and sediment transport simulation applied to landscape dynamics modelling
Authors: Salles Tristan , Duclaux Guillaume 
Published: November 2014

AbstractWe present a new numerical approach for simulating geomorphic and stratigraphic processes that combines open‐channel flow with non‐uniform sediment transport law and semi‐empirical diffusive mass wasting. It is designed to facilitate modelling of surface processes across multiple space‐ and time‐scales, and under a variety of environmental and tectonic conditions. The physics of open‐channel flow is primarily based on an adapted Lagrangian formulation of shallow‐water equations. The interaction between flow and surface geology is performed by a non‐uniform total‐load sediment transport law. Additional hillslope processes are simulated using a semi‐empirical method based on a diffusion approach. In the implementation, the resolution of flow dynamics is made on a triangulated grid automatically mapped and adaptively remeshed over a regular orthogonal stratigraphic mesh. These new methods reduce computational time while preserving stability and accuracy of the physical solutions. In order to illustrate the potential of this method for landscape and sedimentary system modelling, we present a set of three generic experiments focusing on assessing the influence of contrasting erodibilities on the evolution of an active bedrock landscape. The modelled ridges morphometrics satisfy established relationships for drainage network geometry and slope distribution, and provide quantitative information on the relative impact of hillslope and channel processes, sediment discharge and alluviation. Our results suggest that contrasting erodibility can stimulate autogenic changes in erosion rate and influence the landscape morphology and preservation. This approach offers new opportunities to investigate joint landscape and sedimentary systems response to external perturbations. The possibility to define and track a large number of materials makes the implementation highly suited to model source‐to‐sink problems where material dispersion is the key question that needs to be addressed, such as natural resources exploration and basin analysis. Copyright © 2014 John Wiley & Sons, Ltd.
Soil moisture response to snowmelt timing in mixed‐conifer subalpine forests
Authors: Harpold Adrian A. , Molotch Noah P. , Musselman Keith N. , Bales Roger C. , Kirchner Peter B. , Litvak Marcy , Brooks Paul D. 
Published: November 2014

AbstractWestern US forest ecosystems and downstream water supplies are reliant on seasonal snowmelt. Complex feedbacks govern forest–snow interactions in which forests influence the distribution of snow and the timing of snowmelt but are also sensitive to snow water availability. Notwithstanding, few studies have investigated the influence of forest structure on snow distribution, snowmelt and soil moisture response. Using a multi‐year record from co‐located observations of snow depth and soil moisture, we evaluated the influence of forest‐canopy position on snow accumulation and snow depth depletion, and associated controls on the timing of soil moisture response at Boulder Creek, Colorado, Jemez River Basin, New Mexico, and the Wolverton Basin, California. Forest‐canopy controls on snow accumulation led to 12–42 cm greater peak snow depths in openversusunder‐canopy positions. Differences in accumulation and melt across sites resulted in earlier snow disappearance in open positions at Jemez and earlier snow disappearance in under‐canopy positions at Boulder and Wolverton sites. Irrespective of net snow accumulation, we found that peak annual soil moisture was nearly synchronous with the date of snow disappearance at all sites with an average deviation of 12, 3 and 22 days at Jemez, Boulder and Wolverton sites, respectively. Interestingly, sites in the Sierra Nevada showed peak soil moisture prior to snow disappearance at both our intensive study site and the nearby snow telemetry stations. Our results imply that the duration of soil water stress may increase as regional warming or forest disturbance lead to earlier snow disappearance and soil moisture recession in subalpine forests. Copyright © 2014 John Wiley & Sons, Ltd.
Spatio‐temporal distribution of actual evapotranspiration in the Indus Basin Irrigation System
Authors: Liaqat Umar Waqas , Choi Minha , Awan Usman Khalid 
Published: November 2014

AbstractStrategic planning of optimal water use requires an accurate assessment of actual evapotranspiration (ETa) to understand the environmental and hydrological processes of the world's largest contiguous irrigation networks, including the Indus Basin Irrigation System (IBIS) in Pakistan. The Surface Energy Balance System (SEBS) has been used successfully for accurate estimations of ETa in different river basins throughout the world. In this study, we examined the application of SEBS using publically available remote sensing data to assess spatial variations in water consumption and to map water stress from daily to annual scales in the IBIS. Ground‐based ETa was calculated by the advection‐aridity method, from nine meteorological sites, and used to evaluate the intra‐annual seasonality in the hydrological year 2009–2010. In comparison with the advection‐aridity, SEBS computed daily ETa was slightly underestimated with a bias of −0.15 mm day−1 during the kharif (wet; April–September) season, and it was overestimated with a bias of 0.23 mm day−1 in the rabi (dry; October–March) season. Monthly values of the ETa estimated by SEBS were significantly (P < 0.05) controlled by mean air temperature and rainfall, among other climatological variables (relative humidity, sunshine hours and wind speed). Because of the seasonal (kharif and rabi) differences in the water and energy budget in the huge canal command areas of the IBIS, ETa and rainfall were positively correlated in the kharif season and were negatively correlated during the rabi season. In addition, analysis of the evaporation process showed that mixed‐cropping and rice–wheat dominated areas had lower and higher water consumption rates, respectively, in comparison with other cropping systems in the basin. Basin areas under water stress were identified by means of spatial variations in the relative evapotranspiration, which had an average value of 0.59 and 0.42 during the kharif and the rabi seasons, respectively. The hydrological parameters used in this study provide useful information for understanding hydrological processes at different spatial and temporal scales. Results of this study further suggest that the SEBS is useful for evaluation of water resources in semi‐arid to arid regions over longer periods, if the data inputs are carefully handled. Copyright © 2014 John Wiley & Sons, Ltd.
A convergence analysis for a sweeping preconditioner for block tridiagonal systems of linear equations
Authors: Bağcı Hakan , Pasciak Joseph E. , Sirenko Kostyantyn Y. 
Published: November 2014

SummaryWe study sweeping preconditioners for symmetric and positive definite block tridiagonal systems of linear equations. The algorithm provides an approximate inverse that can be used directly or in a preconditioned iterative scheme. These algorithms are based on replacing the Schur complements appearing in a block Gaussian elimination direct solve by hierarchical matrix approximations with reduced off‐diagonal ranks. This involves developing low rank hierarchical approximations to inverses. We first provide a convergence analysis for the algorithm for reduced rank hierarchical inverse approximation. These results are then used to prove convergence and preconditioning estimates for the resulting sweeping preconditioner. Copyright © 2014 John Wiley & Sons, Ltd.
Dynamics of pulmonary venous flow in fetuses with intrauterine growth restriction
Authors: Bravo‐Valenzuela Nathalie J. M. , Zielinsky Paulo , Huhta James C. , Acacio Gregório L. , Nicoloso Luiz H. , Piccoli Antonio , Busato Stefano , Klein Caroline 
Published: November 2014

AbstractObjectiveTo test the hypothesis that the pulmonary vein pulsatility index (PVPI) is higher in fetuses with growth restriction (IUGR) than in normal fetuses.MethodsTwenty‐two fetuses with IUGR and twenty‐one (21) fetuses with appropriate growth for gestational age from healthy mothers were studied. PVPI was calculated by Doppler echocardiography [maximal velocity (systolic or diastolic peak) − pre‐systolic peak / mean velocity]. Obstetric ultrasound was used to assess fetal biometry and Doppler to assess the uterine, umbilical and middle cerebral arteries PI. Statistical analysis used t test and Pearson's correlation.ResultsMean gestational age was 31.5 +/− 2.1 weeks in the control group and 31.4 +/− 3.1 weeks in IUGR (P = 0.91). The PI of uterine and umbilical arteries were higher in IUGR than in controls (P < 0.001). Mean PVPI in IUGR fetuses was 1.31 +/− 0.41, and in controls it was 0.83 +/− 0.11 (P < 0.001).ConclusionThe pulsatility index of pulmonary venous flow in fetuses with growth restriction is higher than in normal fetuses, probably as a result of left atrial dynamics alteration secondary or not to fetal left ventricular diastolic dysfunction. © 2014 John Wiley & Sons, Ltd.
RSV: Immunoprophylaxis and non‐invasive respiratory support in ex‐preterms: A northern UK perspective
Authors: Tinnion Robert , Spencer Jill , Moss Samantha , Fenton Alan 
Published: November 2014

SummaryRecent guidance has suggested that immunoprophylaxis with monoclonal antibody against respiratory syncytial virus (RSV) should be extended to ex‐preterm infants who are moderate‐to‐late‐preterm and discharged home during the RSV season. Noninvasive respiratory support (NIV) for infants with bronchiolitis is becoming widespread with little supporting evidence for efficacy over nonpressure support methods. We used multicentre prospective audit and service evaluation to evaluate whether extension of current practice in line with the guidance would provide a clinical or cost benefit, and whether NIV provides any benefits in the ex‐preterm population. The prevalence of bronchiolitic illness requiring admission in our population was similar to other studies (2.5%). We found that the majority of ex‐preterm infants with RSV positive bronchiolitis who required NIV did not meet the extended criteria for immunisation. Our data suggest that extending RSV prophylaxis as recommended would be unlikely to reduce numbers of infants requiring respiratory support for RSV. NIV use has been widely adopted (9% of ‘bronchiolitic’ admissions) in our region but the data do not support it as a useful adjunct for ex‐preterms with RSV positive illness requiring respiratory support: it does not appear to reduce the need for subsequent formal ventilation. Our study does not support a case for change to more widespread, protocol driven immunisation for RSV. Further research is needed in a randomised, controlled setting to examine the use of NIV in bronchiolitis in a wider context. Pediatr Pulmonol. 2015; 50:1119–1127. © 2014 Wiley Periodicals, Inc.