bluuebunny/crossref_metadata_2025_split huggingface dataset:
A 66‐year tropical cyclone record for south‐east Africa: temporal trends in a global context
Authors: Fitchett Jennifer M. , Grab Stefan W. 
Published: February 2014

ABSTRACTThis study investigates changes in the frequency and timing of tropical cyclone landfalls over the south‐west Indian Ocean during the last 66 years. Little is known about the spatial and temporal trends of such storm landfalls during recent historical times, specifically the last ca. 100 years. By analysing three storm track records spanning periods of 66–161 years, we establish that much of the perceived change in storm numbers can be attributed to improvements in storm detection methods over the past century. Furthermore, we find no statistically significant trends in the frequency of tropical cyclone landfalls over Madagascar and Mozambique over the past 6 decades, despite more comprehensive records during the most recent period. There is, however, considerable interannual variability in the number of storms making landfall over the countries investigated; most probably driven by cyclical atmospheric forcing, including El Niño‐Southern Oscillation (ENSO) and the Quasi‐Biennial Oscillation (QBO). Recent trends indicate an increasing number of tropical cyclones tracking to the south of Madagascar, potentially associated with the southward shift of the 26 °C isotherm, combined with a decrease in the steering flow during La Niña years.
Statistical downscaling of multi‐site daily rainfall in a South Australian catchment using a Generalized Linear Model
Authors: Beecham Simon , Rashid Mamunur , Chowdhury Rezaul K. 
Published: February 2014

ABSTRACTThe intention of this study was to identify a suitable Generalized Linear Model (GLM) for modelling multi‐site daily rainfall in the Onkaparinga catchment in South Australia and to examine the suitability of the model for downscaling of General Circulation Model (GCM) rainfall projections. A GLM was applied and multi‐site daily rainfall was downscaled using National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis datasets. Nineteen large‐scale atmospheric and circulation variables were selected at first and these were eventually reduced, based on correlation with daily rainfall, to 10 final variables to be used in the model. First, logistic regression was used to identify the wet and dry days, then wet day rainfall was modelled using a gamma distribution. The model was fitted for a calibration period (1991–2010) and it was then validated over the period 1981–1990. Several summary statistics including mean, standard deviation, number of wet days, maximum rainfall amount and lag 1 and lag 2 autocorrelations were used to check the model performance. The 2.5th and 97.5th percentiles of the simulated rainfall statistics were plotted against the observed rainfall statistics and it was shown that most of the observed statistics were within these bounds. Area averaged and station wise monthly, seasonal and annual totals for observed and simulated rainfall were estimated and compared. The overall performance of the GLM to downscale rainfall was considered satisfactory. However, a few discrepancies were observed in different performance statistics. Parameterization of the model to capture the local convective variability of rainfall would increase the model performance. It was found overall that the GLM can be applied for downscaling of GCM rainfall projections for this catchment.
Homogenization of monthly precipitation time series in Croatia
Authors: Zahradníček Pavel , Rasol Dubravka , Cindrić Ksenija , Štěpánek Petr 
Published: February 2014

ABSTRACTVarious types of studies require a sufficiently long series of data processed identically over the entire area. For climate analysis, it is necessary that analysed time series are homogeneous, which means that their variations are caused only by variations in weather and climate. Unfortunately, most of the climatological series are inhomogeneous and contain outliers that may significantly affect the analysis results. The 137 stations with precipitation measurement belonging to the meteorological station network governed by the Meteorological and Hydrological Service of Croatia were selected for the present analysis. Most of the data series cover a period from the late 1940s or early 1950s through the year 2010. For quality control and homogenization, an approach based on the software ProClimDB/Anclim was applied. In this study, we describe the results from the quality control and homogenization process for monthly precipitation sums as well as the spatial relationship of precipitation in the Croatian region. The precipitation network in Croatia is fairly homogeneous as only 23% of the 137 analysed stations are found to be inhomogeneous.
Statistical downscaling methods based on APCC multi‐model ensemble for seasonal prediction over South Korea
Authors: Kang Suchul , Hur Jina , Ahn Joong‐Bae 
Published: February 2014

ABSTRACTAn investigation was conducted to optimize the application of the multi‐model ensemble (MME) technique for statistical downscaling using 1‐ to 6‐month lead hindcasts obtained from six operational coupled general circulation models (GCMs) participating in the APEC Climate Center (APCC) MME prediction system. Three different statistical downscaling MME methods (SDMMEs) were compared and estimated over South Korea. The study results revealed that under the same number of ensemble members, simple changes in the statistical downscaling method, such as an applicative order or a type of MME, can help to improve the predictability. The first method, the conventional technique, performed MME using data downscaled from the single‐model ensemble means of each GCM (SDMME‐Sm), whereas the second and third methods, newly designed in this study, calculated the simple ensemble mean (SDMME‐Ae) and the weighted ensemble mean (SDMME‐We) after statistical downscaling for each member of all model ensembles. These three methods were applied to predict temperature and precipitation for the 6‐month summer‐fall season over 23 years (1983–2005) at 60 weather stations over South Korea. The predictors were variables from hindcasts integrated by the six coupled GCMs. According to the analysis, both SDMME‐Ae and SDMME‐We showed increased predictability compared with SDMME‐Sm. In particular, SDMME‐We showed more significant improvement in long‐term prediction. In addition, in order to assess the dependence of predictability on the number of downscaled ensemble members and the type of MME, an additional experiment was performed, the results of which revealed that the model performance was closely related to the number of downscaled ensemble members. However, after approximately 30 ensemble members, the predictive skills became rapidly saturated when using the SDMME‐Ae method. SDMME‐We overcame the limited skills that can be achieved by merely increasing the number of downscaled ensemble members, thereby improving the performance.
Team Proactivity as a Linking Mechanism between Team Creative Efficacy, Transformational Leadership, and Risk‐Taking Norms and Team Creative Performance
Authors: Shin Yuhyung , Eom Chanyoung 
Published: February 2014

AbstractDespite the growing body of research on creativity in team contexts, very few attempts have been made to explore the team‐level antecedents and the mediating processes of team creative performance on the basis of a theoretical framework. To address this gap, drawing on Paulus and Dzindolet's (2008) group creativity model, this study proposed team creative efficacy, transformational leadership, and risk‐taking norms as antecedents of team creative performance and team proactivity as an intervening mechanism between these relationships. The results of team‐level regression analyses conducted on the leaders and members of 103 Korean work teams showed that team creative efficacy and risk‐taking norms were positively associated with team creative performance. Furthermore, the relationships between team creative efficacy and team creative performance and between risk‐taking norms and team creative performance were mediated by team proactivity. These findings offer new insights regarding the antecedents and the mediator of creative performance in team contexts and important implications for theory and practice.
How strawberry plants cope with limited phosphorus supply: Nursery‐crop formation and phosphorus and nitrogen uptake dynamics
Authors: Li Hong , Li Tingxian , Fu Gang , Hu Kelin 
Published: February 2014

AbstractHealthy, well‐rooted planting stocks are important for profitable fruit production of strawberry (Fragaria × ananassa Duch.). Adequate nutrient inputs and crop‐rotation practices are among the most important measures to insure a successful, rapid development of strawberry nursery plants. However, relationships between macronutrient use and strawberry‐nursery‐plant formation in different rotation environments are not well understood. Our objectives were to assess strawberry plant P : N nutrition and nursery development under various limited and unlimited P inputs applied at different growth stages and to examine how nursery plants cope with limited P inputs. The field studies were conducted in a wheat–ryegrass–ryegrass–strawberry (WRRS) system in 2008 and in another corn–ryegrass–ryegrass–strawberry (CRRS) system in 2009 in Nova Scotia, Canada. The nursery crop was cv. Strawberry Festival and the experimental treatments consisted of three mother‐stock P (MSP) rates (0, 6.6, and13.2 P kg ha–1) and five daughter‐plant P (DPP) rates (0, 13.2, 26.4, 39.6, and 52.8 kg P ha–1), representing 0%–125% of the regional recommendations for strawberry nursery. The P treatments were arranged with three blocks in a split‐plot design in each field. The results showed that the effects and interactions of the MSP and DPP treatments were significant (P < 5%) on whole‐plant P and N acquisition and nursery productivity. Two‐year whole‐plant total P and N acquisition varied between (13.2 ± 2.0) kg P ha–1 and (46 ± 7.3) kg N ha–1 (n = 270) in both nursery systems. There was a quadratic regression relationship between nursery runners and daughter plants with plant P and N acquisition (0.33 < R<?h.3>2 < 0.42, P < 5%). Soil pH levels declined with time and were positively correlated with nursery‐plant formation. Too many runners (18–22 per mother stock) might reduce nursery‐plant formation. Limited P inputs (37.5%–62.5% of regular recommendation) might result in a suitable plant P : N ratio (0.12–0.13) and adequate daughter plant‐to‐runner ratios (1.4–1.7) for optimum nursery formation (14–16 daughter plants per mother stock). Nutrient P was the single controlled factor influencing the N acquisition of nursery plants. High P inputs (> 39.6 P ha–1 or > 75% of regular recommendation) may harm the crops. Therefore, this study implies that low‐input horticulture can improve the nutrition management of strawberry nursery.
Effect of ultrasonic power on soil organic carbon fractions
Authors: Poeplau Christopher , Don Axel 
Published: February 2014

AbstractUltrasonic dispersion is a prevalent tool for soil fractionation. It is widely ignored that variation in ultrasonic power might lead to significantly different dispersion. We evaluated the effect of power variation with constant energy on the fine fraction mass, its organic C content and quality. All parameters increased significantly with power. The term “stable aggregates” as used in fractionation schemes cannot be defined by ultrasonic energy alone but power needs to be standardized, too.
Fragmented pattern of tumor regression and lateral intramural spread may influence margin appropriateness after TEM for rectal cancer following neoadjuvant CRT
Authors: Perez Rodrigo O. , Habr‐Gama Angelita , Smith Fraser M. , Kosinski Lauren , São Julião Guilherme P. , Grzona Esteban , Rawet Viviane , Vianna Maria Regina , Proscurshim Igor , Lynn Patrício Bernardo , Gama‐Rodrigues Joaquim 
Published: February 2014

ABSTRACTBackgroundThe main tenets of local excision of rectal cancer following neoadjuvant chemoradiation (CRT) are that the mucosal scar represents the main focus of residual disease and a solid conglomerate around this rather than being scattered (fragmented) through the bowel wall.MethodsRetrospective review of a prospective cohort of patients with residual rectal ycT1‐2N0 adenocarcinoma with small residual tumors (≤3 cm) following CRT who underwent transanal endoscopic microsurgery (TEM) with 1‐cm margins around the residual mucosal abnormality was performed. Distribution and morphology (solid vs. fragmented) of tumor spread were studied and correlated to postoperative oncological outcomes.ResultsThirty patients were included. Twenty percent (n = 6) were ypT1, 60% (n = 18) were ypT2, and 20% (n = 6) were ypT3 tumors. Fragmentation was present in 37%. The mean distance between foci of residual scattered tumor was 3.6 ± 2.0 mm. Lateral spread under normal mucosa was present in 19 specimens (53%; mean extension 4.8 ± 2.4 mm). With a median follow up of 32 months, none of these findings impacted upon development of recurrence.ConclusionsBoth occult lateral spread and fragmented tumor patterns are common findings after CRT. Despite the potential of occult spread to mislead surgeon choice of resection margin, its presence did not influence oncological outcome in this series. J. Surg. Oncol. 2014 109:853–858. © 2014 Wiley Periodicals, Inc.
The Implication of 1,3‐Dipolar Cycloaddition of Azomethine Ylides to the Synthesis of Main‐Chain Porphyrin Oligomers
Authors: Konev Alexander S. , Lukyanov Daniil A. , Vlasov Petr S. , Levin Oleg V. , Virtsev Alexander A. , Kislyakov Ivan M. , Khlebnikov Alexander F. 
Published: February 2014

The polycycloaddition of azomethine ylides to dipolarophiles is described for the first time. Use of (cis,cis)‐bis‐aziridines as a source of azomethine ylides allows selective polyaddition to be realized, which leads to oligomers exclusively with trans‐substituted pyrrolidine rings and modest molecular weights (ca. 5–10 kDa). The fluorescent, electrochemical, electrochromic, and non‐linear optical properties of the main‐chain free‐base porphyrin oligomer, synthesized by the developed procedure, are studied. An enhancement of the optical power limiting effect in a porphyrin oligomer solution is registered against that of the monomer.
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Microwave‐Assisted Synthesis of Glycopolymer‐Functionalized Silver Nanoclusters: Combining the Bioactivity of Sugar with the Fluorescence and Cytotoxicity of Silver
Authors: Lu Wei , Ma Wenjuan , Lu Jiawei , Li Xiao , Zhao Yun , Chen Gaojian 
Published: February 2014

Copolymers of 2‐(methacrylamido)glucopyranose (MAG) and methacrylic acid (MAA) are synthesized by RAFT polymerization and then used as templates to prepare glycopolymer‐functionalized Ag nanoclusters (Gly‐Ag NCs) through microwave irradiation. Polymers and the resulting nanoclusters are characterized by NMR, GPC, UV‐Vis, SEM, TEM, AAS and fluorescence spectroscopy. The bio‐activity of the fluorescent Gly‐Ag NCs are further examined using GLUT‐1 over‐expressing cancer cells K562. Gly‐Ag NCs show efficient binding ability toward K562 cells and inhibit the cell viability in a dose dependent manner (IC50 = 0.65 μg mL–1), indicating their potential biological applications for both cancer imaging and targeted cancer therapy.
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Cross‐talk Between Host, Microbiome and Probiotics: A Systems Biology Approach for Analyzing the Effects of Probiotic Enterococcus faecium NCIMB 10415 in Piglets
Authors: Twardziok S. O. , Pieper R. , Aschenbach J. R. , Bednorz C. , Brockmann G. A. , Fromm M. , Klingspor S. , Kreuzer S. , Lodemann U. , Martens H. , Martin L. , Richter J. F. , Scharek‐Tedin L. , Siepert B. F. , Starke I. C. , Tedin K. , Vahjen W. , Wieler L. H. , Zakrzewski S. S. , Zentek J. , Wrede P. 
Published: February 2014

AbstractA comprehensive data‐set from a multidisciplinary feeding experiment with the probiotic Enterococcus faecium was analyzed to elucidate effects of the probiotic on growing piglets. Sixty‐two piglets were randomly assigned to a control (no probiotic treatment) and a treatment group (E. faecium supplementation). Piglets were weaned at 26 d. Age‐matched piglets were sacrificed for the collection of tissue samples at 12, 26, 34 and 54 d. In addition to zootechnical data, the composition and activity of intestinal microbiota, immune cell types, and intestinal responses were determined. Our systems analysis revealed clear effects on several measured variables in 26 and 34 days old animals, while response patterns varied between piglets from different age groups. Correlation analyses identified reduced associations between intestinal microbial communities and immune system reactions in the probiotic group. In conclusion, the developed model is useful for comparative analyses to unravel systems effects of dietary components and their time resolution. The model identified that effects of E. faecium supplementation most prominently affected the interplay between intestinal microbiota and the intestinal immune system. These effects, as well as effects in other subsystems, clustered around weaning, which is the age where piglets are most prone to diarrhea.
Gadofosveset‐based biomarker of tissue albumin concentration: Technical validation in vitro and feasibility in vivo
Authors: Richardson Owen C. , Bane Octavia , Scott Marietta L.J. , Tanner Steven F. , Waterton John C. , Sourbron Steven P. , Carroll Timothy J. , Buckley David L. 
Published: February 2014

PurposeThere is currently no adequate method of mapping physiologic and pathophysiologic tissue albumin concentrations in human subjects. The objective of this study was to devise and evaluate a biomarker of regional albumin concentration using gadofosveset‐enhanced MRI.Theory and MethodsA binding and relaxation model was devised and evaluated in vitro in solutions of albumin at 3.0 Tesla (T) and 4.7T. The method was evaluated in the heart in seven volunteers at 3.0T.ResultsMRI‐derived estimates of albumin concentration were in good agreement with true values over the range 0.1–1.0 mM (Pearson correlation coefficients of 0.85 and 0.88 for 3.0T and 4.7T, respectively). The mean calculated albumin concentration in the myocardium for the volunteers was 0.02 mM (range, 0.01–0.03 mM).ConclusionAccurate estimates of albumin concentration in vitro suggest this may be a viable noninvasive alternative to existing techniques. In the myocardium the MRI‐derived estimates of albumin concentration indicate the practical feasibility of the technique but were below expected values. Gadofosveset‐enhanced MR relaxometry has potential in providing biomarkers of regional albumin concentration; further evaluation is required before it can be used reliably in vivo. Magn Reson Med 73:244–253, 2015. © 2014 Wiley Periodicals, Inc.
Cross‐sectional area reference values of nerves in the lower extremities using ultrasonography
Authors: Seok Hung Youl , Jang Jae Hong , Won Sun Jae , Yoon Joon Shik , Park Kyung Seok , Kim Byung-Jo 
Published: February 2014

ABSTRACTIntroduction: Cross‐sectional area (CSA) reference values of lower extremity nerves using ultrasonography have only been reported in a few studies and have been limited to white populations. Methods: For this study, 94 healthy Korean volunteers were recruited for measurement of the CSA at 7 sites of lower extremity nerves. The side‐to‐side difference in CSA was calculated for each nerve, and reference ranges were derived. External validity evaluation for the reference values was performed with 10 newly recruited volunteers at a different institution. Results: Nerve CSA was correlated significantly with body mass index, weight, and height; however, the absolute value of the side‐to‐side difference had no significant correlation with demographic factors. The external validity was adequate for all sites, ranging from 80% to 100%. Conclusions: The lower extremity nerve CSA values obtained in this study may provide normal reference values for the Asian population. Muscle Nerve 50: 564–570, 2014
Effects of electrical stimulation pattern on quadriceps force production and fatigue
Authors: Deley Gaelle , Laroche Davy , Babault Nicolas 
Published: February 2014

ABSTRACTIntroduction: Mixed stimulation programs (MIX) that switch from constant frequency trains (CFT) to variable frequency trains have been proposed to offset the rapid fatigue induced by CFT during electrical stimulation. However, this has never been confirmed with long stimulation patterns, such as those used to evoke functional contractions. The purpose of this study was to test the hypothesis that MIX programs were less fatiguing than CFTs in strength training‐like conditions (6‐s contractions, 30‐min). Methods: Thirteen healthy subjects underwent 2 sessions corresponding to MIX and CFT programs. Measurements included maximal voluntary isometric torque and torque evoked by each contraction. Results: There were greater decreases of voluntary and evoked torque (P < 0.05) after CFT than MIX, and mean torque was 13 ± 1% higher during the MIX session (P < 0.05). Conclusions: These findings confirm that combining train types might be a useful strategy to offset rapid fatigue during electrical stimulation sessions with long‐duration contractions. Muscle Nerve 49: 760–763, 2014
Multigrid with FFT smoother for a simplified 2D frictional contact problem
Authors: Zhao Jing , Vollebregt Edwin A. H. , Oosterlee Cornelis W. 
Published: February 2014

SUMMARYThis paper aims to develop a fast multigrid (MG) solver for a Fredholm integral equation of the first kind, arising from the 2D elastic frictional contact problem. After discretization on a rectangular contact area, the integral equation gives rise to a linear system with the coefficient matrix being dense, symmetric positive definite and Toeplitz. A so‐called fast Fourier transform (FFT) smoother is proposed. This is based on a preconditioner M that approximates the inverse of the original coefficient matrix, and that is determined using the FFT technique. The iterates are then updated by Richardson iteration: adding the current residuals preconditioned with the Toeplitz preconditioner M. The FFT smoother significantly reduces most components of the error but enlarges several smooth components. This causes divergence of the MG method. Two approaches are studied to remedy this feature: subdomain deflation (SD) and row sum modification (RSM). MG with the FFT + RSM smoother appears to be more efficient than using the FFT + SD smoother. Moreover, the FFT + RSM smoother can be applied as an efficient iterative solver itself. The two methods related to RSM also show rapid convergence in a test with a wavy surface, where the Toeplitz structure is lost. Copyright © 2014 John Wiley & Sons, Ltd.
Smoothed aggregation algebraic multigrid for stochastic PDE problems with layered materials
Authors: Brezina Marian , Doostan Alireza , Manteuffel Tom , McCormick Steve , Ruge John 
Published: February 2014

SUMMARYWe consider two algebraic multilevel solvers for the solution of discrete problems arising from PDEs with random inputs. Our focus is on problems with large jumps in material coefficients. The model problem considered is that of a diffusion problem with uncertainties in the diffusion coefficients and realization values differing dramatically between different layers in the spatial domain, with the location of the interfaces between the layers assumed to be known. The stochastic discretization is based on the generalized polynomial chaos, and the spatial problem is discretized using conforming finite elements. A multigrid solver based on smoothed aggregation is presented, and numerical experiments are provided demonstrating convergence properties of the multigrid solver. The observed convergence is shown to depend only weakly on the stochastic discretization and, for the discretized stochastic PDE problem, generally mimics that of the corresponding deterministic problem. Copyright © 2014 John Wiley & Sons, Ltd.