bluuebunny/crossref_metadata_2025 huggingface dataset:
Increase in hippocampal theta oscillations during spatial decision making
Authors: Belchior Hindiael , Lopes‐dos‐Santos Vítor , Tort Adriano B.L. , Ribeiro Sidarta
Published: February 2014

The processing of spatial and mnemonic information is believed to depend on hippocampal theta oscillations (5–12 Hz). However, in rats both the power and the frequency of the theta rhythm are modulated by locomotor activity, which is a major confounding factor when estimating its cognitive correlates. Previous studies have suggested that hippocampal theta oscillations support decision‐making processes. In this study, we investigated to what extent spatial decision making modulates hippocampal theta oscillations when controlling for variations in locomotion speed. We recorded local field potentials from the CA1 region of rats while animals had to choose one arm to enter for reward (goal) in a four‐arm radial maze. We observed prominent theta oscillations during the decision‐making period of the task, which occurred in the center of the maze before animals deliberately ran through an arm toward goal location. In speed‐controlled analyses, theta power and frequency were higher during the decision period when compared to either an intertrial delay period (also at the maze center), or to the period of running toward goal location. In addition, theta activity was higher during decision periods preceding correct choices than during decision periods preceding incorrect choices. Altogether, our data support a cognitive function for the hippocampal theta rhythm in spatial decision making. © 2014 The Authors Hippocampus Published by Wiley Periodicals, Inc.
Spatial memory in sedentary and trained diabetic rats: Molecular mechanisms
Authors: Diegues João Carlos , Pauli José Rodrigo , Luciano Eliete , de Almeida Leme José Alexandre Curiacos , de Moura Leandro Pereira , Dalia Rodrigo Augusto , de Araújo Michel Barbosa , Sibuya Clarice Yoshiko , de Mello Maria Alice Rostom , Gomes Ricardo José
Published: February 2014

Diabetes mellitus is a chronic disease that has been associated with memory loss, neurological disorders, and Alzheimer's disease. Some studies show the importance of physical exercise to prevent and minimize various neurological disorders. It is believed that the positive effects of exercise on brain functions are mediated by brain insulin and insulin‐like growth factor‐1 (IGF‐1) signaling. In this study, we investigate the role of swimming exercise training on hippocampus proteins related to insulin/IGF‐1 signaling pathway in Type 1 diabetic rats and its effects on spatial memory. Wistar rats were divided into four groups namely sedentary control, trained control, sedentary diabetic (SD), and trained diabetic (TD). Diabetes was induced by Alloxan (ALX) (32 mg/kg b.w.). The training program consisted in swimming 5 days/week, 1 h/day, per 6 weeks, supporting an overload corresponding to 90% of the anaerobic threshold. We employed ALX‐induced diabetic rats to explore learning and memory abilities using Morris water maze test. At the end of the training period, the rats were sacrificed 48 h after their last exercise bout when blood samples were collected for serum glucose, insulin, and IGF‐1 determinations. Hippocampus was extracted to determinate protein expression (IR, IGF‐1R, and APP) and phosphorylation (AKT‐1, AKT‐2, Tau, and β‐amyloide proteins) by Western Blot analysis. All dependent variables were analyzed by two‐way analysis of variance with significance level of 5%. Diabetes resulted in hyperglycemia and hypoinsulinemia in both SD and TD groups (P < 0.05); however, in the training‐induced group, there was a reduction in blood glucose in TD. The average frequency in finding the platform decreased in SD rats; however, exercise training improved this parameter in TD rats. Aerobic exercise decreased Tau phosphorylation and APP expression, and increased some proteins related to insulin/IGF‐1 pathway in hippocampus of diabetic rats. Thus, these molecular adaptations from exercise training might contribute to improved spatial learning and memory in diabetic organisms. © 2014 Wiley Periodicals, Inc.
The Role of the Interaction Frame in the Theoretical Description of Solid Effect Dynamic Nuclear Polarization
Authors: Kwiatkowski Grzegorz , Karabanov Alexander , Köckenberger Walter
Published: February 2014

The enhancement of the nuclear spin polarization generated by dynamic nuclear polarization depends on two competing processes: the perturbation of the thermal equilibrium by the applied microwave field and the tendency of relaxation processes to re‐establish the thermal state. Hence, it is important to correctly incorporate relaxation processes in the theoretical description of dynamic nuclear polarization to obtain meaningful simulations. A difficulty arises in the choice of the correct interaction frame when building an appropriate relaxation superoperator. In the Zeeman frame, the rate constants introduced to define longitudinal and transverse relaxation can become mixed if the non‐secular part of the hyperfine interaction between an electron in a paramagnetic centre and the nuclear spins is strong. Deriving the relaxation superoperator in the interaction frame that is defined by the eigenbasis of the stationary Hamiltonian eliminates this issue. However, when using this strategy, not all the non‐secular terms arising in a relaxation model based on local magnetic field fluctuations are taken properly into account if dipolar interactions between nuclear spins dominate over hyperfine interactions. An analytical treatment of this problem is presented that is corroborated by a set of numerical simulations focussing on the case of solid effect dynamic nuclear polarization. The advantage and possible errors arising when using either of the two strategies are briefly summarised and discussed.
Emotional suppression and well‐being in immigrants and majority group members in the Netherlands
Authors: Stupar Snežana , van de Vijver Fons J. R. , Fontaine Johnny R. J.
Published: February 2014

We were interested in interethnic differences in emotional suppression. We propose a model in which suppression of specific emotional experiences (suppressive behaviours during interactions with others) mediates the relationship between emotional suppression tendency (intention to suppress emotions) and well‐being, operationalised as mood disturbance, life dissatisfaction and depressive and physical symptoms. The sample consisted of 427 majority group members and 344 non‐Western and 465 Western immigrants in the Netherlands. Non‐Western immigrants scored higher on emotional suppression tendency and lower on well‐being than the other groups. We did not find interethnic differences in suppression of specific emotional experiences. The full mediation model was supported in all groups. Interethnic differences in well‐being could not be accounted for by differences in emotional suppression.
The effects of presenting delays before and after task completion on self‐control responding in children with behavior disorders
Authors: Gadaire Dana M. , Fisher Wayne W. , Steege Mark
Published: February 2014

We examined relations between self‐control responding and environmental variables with 3 children with behavior disorders. Differential delays were presented before or after task completion in a single‐session reversal design. Delays presented before task completion produced more impulsive responding than those presented after task completion for all participants.
Growth evaluation method by live imaging of Daphnia magna and its application to the estimation of an insect growth regulator
Authors: Suzuki Akiko , Kato Yasuhiko , Matsuura Tomoaki , Watanabe Hajime
Published: February 2014

The zooplankton Daphnia magna has been widely used as a test organism to assess the toxicity of chemical substances because of its important position in aquatic ecology and its ease of handling. Among the various endpoints for toxicity evaluation, growth rate is one of the most critical and many studies have been conducted. However, measurement of growth rate was time‐consuming and not an ideal endpoint in terms of screening. In this study, we demonstrated a live imaging method to monitor the growth of daphnids by area measurement. In this method, daphnid images were directly obtained from a swimming chamber and these images were processed for the evaluation of growth. The reliability of this method was confirmed by comparison with the conventional dry weight method of the same animals. The body area of daphnids using this method showed a strong correlation with the dry weight method, with R2 = 0.930. In addition, we quantified the effect of a toxicant, fenoxycarb, on the growth of the animal. Fenoxycarb concentrations of 0, 0.027, 0.27 and 2.7 µg l–1 were tested and their effects on growth were estimated by the live imaging method. In the toxicity test, the area of daphnids decreased significantly with increasing fenoxycarb concentration. These results indicate that the present live imaging method is a reliable approach for daphnid toxicity testing. This method is promising for high‐throughput Daphnia toxicity tests and real‐time individual observations. Copyright © 2014 John Wiley & Sons, Ltd.
Predictors of Excess Mortality After Fracture: A Population-Based Cohort Study
Authors: Melton L Joseph , Atkinson Elizabeth J , Sauver Jennifer L St. , Achenbach Sara J , Therneau Terry M , Rocca Walter A , Amin Shreyasee
Published: February 2014

To determine the extent to which excess mortality after fractures attributable to particular causes at specific skeletal sites can be predicted using data about all medical diagnoses, we conducted a historical cohort study among 1991 Olmsted County, Minnesota, residents aged ≥50 years who experienced any fracture in 1989 to 1991 and who were followed passively for up to 22 years for death from any cause. We used a machine learning approach, gradient boosting machine (GBM) modeling, to determine whether the comorbid conditions present at the time of fracture and those that arose subsequently could, in aggregate, identify patients at the greatest increased risk of death. During 21,867 person-years of follow-up, 1245 deaths were observed when 1061 were expected (standardized mortality ratio, 1.2; 95% confidence interval [CI] 1.1–1.2). Patients presented with a median history of 26 comorbid conditions each as assessed by the Clinical Classification Software system and 57 each over the total duration of follow-up. Using all available information, the excess deaths could be predicted with good accuracy (c-index ≥0.80) in 89% of the GBM models built for patients with different types of fracture; in one-third of the models, the c-index was ≥0.90. The conditions most prominent in the GBM prediction models were also reflected in the specific causes of death that were elevated, suggesting the influence of confounding on the relationship. However, the predominant comorbid conditions were mainly those responsible for mortality in the general population, rather than the specific diseases most closely associated with secondary osteoporosis. To reduce long-term deaths in the fracture population as a whole, a more general approach to the fracture patient is indicated. © 2014 American Society for Bone and Mineral Research.
Effects of Odanacatib on the Radius and Tibia of Postmenopausal Women: Improvements in Bone Geometry, Microarchitecture, and Estimated Bone Strength
Authors: Cheung Angela M , Majumdar Sharmila , Brixen Kim , Chapurlat Roland , Fuerst Thomas , Engelke Klaus , Dardzinski Bernard , Cabal Antonio , Verbruggen Nadia , Ather Shabana , Rosenberg Elizabeth , de Papp Anne E
Published: February 2014

The cathepsin K inhibitor odanacatib (ODN), currently in phase 3 development for postmenopausal osteoporosis, has a novel mechanism of action that reduces bone resorption while maintaining bone formation. In phase 2 studies, odanacatib increased areal bone mineral density (aBMD) at the lumbar spine and total hip progressively over 5 years. To determine the effects of ODN on cortical and trabecular bone and estimate changes in bone strength, we conducted a randomized, double-blind, placebo-controlled trial, using both quantitative computed tomography (QCT) and high-resolution peripheral (HR-p)QCT. In previously published results, odanacatib was superior to placebo with respect to increases in trabecular volumetric BMD (vBMD) and estimated compressive strength at the spine, and integral and trabecular vBMD and estimated strength at the hip. Here, we report the results of HR-pQCT assessment. A total of 214 postmenopausal women (mean age 64.0 ± 6.8 years and baseline lumbar spine T-score –1.81 ± 0.83) were randomized to oral ODN 50 mg or placebo, weekly for 2 years. With ODN, significant increases from baseline in total vBMD occurred at the distal radius and tibia. Treatment differences from placebo were also significant (3.84% and 2.63% for radius and tibia, respectively). At both sites, significant differences from placebo were also found in trabecular vBMD, cortical vBMD, cortical thickness, cortical area, and strength (failure load) estimated using finite element analysis of HR-pQCT scans (treatment differences at radius and tibia = 2.64% and 2.66%). At the distal radius, odanacatib significantly improved trabecular thickness and bone volume/total volume (BV/TV) versus placebo. At a more proximal radial site, odanacatib attenuated the increase in cortical porosity found with placebo (treatment difference = –7.7%, p = 0.066). At the distal tibia, odanacatib significantly improved trabecular number, separation, and BV/TV versus placebo. Safety and tolerability were similar between treatment groups. In conclusion, odanacatib increased cortical and trabecular density, cortical thickness, aspects of trabecular microarchitecture, and estimated strength at the distal radius and distal tibia compared with placebo. © 2014 American Society for Bone and Mineral Research
High-Resolution Genome Screen for Bone Mineral Density in Heterogeneous Stock Rat
Authors: Alam Imranul , Koller Daniel L , Cañete Toni , Blázquez Gloria , López-Aumatell Regina , Martínez-Membrives Esther , Díaz-Morán Sira , Tobeña Adolf , Fernández-Teruel Alberto , Stridh Pernilla , Diez Margarita , Olsson Tomas , Johannesson Martina , Baud Amelie , Econs Michael J , Foroud Tatiana
Published: February 2014

We previously demonstrated that skeletal mass, structure, and biomechanical properties vary considerably in heterogeneous stock (HS) rat strains. In addition, we observed strong heritability for several of these skeletal phenotypes in the HS rat model, suggesting that it represents a unique genetic resource for dissecting the complex genetics underlying bone fragility. The purpose of this study was to identify and localize genes associated with bone mineral density in HS rats. We measured bone phenotypes from 1524 adult male and female HS rats between 17 and 20 weeks of age. Phenotypes included dual-energy X-ray absorptiometry (DXA) measurements for bone mineral content and areal bone mineral density (aBMD) for femur and lumbar spine (L3–L5), and volumetric BMD measurements by CT for the midshaft and distal femur, femur neck, and fifth lumbar vertebra (L5). A total of 70,000 polymorphic single-nucleotide polymorphisms (SNPs) distributed throughout the genome were selected from genotypes obtained from the Affymetrix rat custom SNPs array for the HS rat population. These SNPs spanned the HS rat genome with a mean linkage disequilibrium coefficient between neighboring SNPs of 0.95. Haplotypes were estimated across the entire genome for each rat using a multipoint haplotype reconstruction method, which calculates the probability of descent for each genotyped locus from each of the eight founder HS strains. The haplotypes were tested for association with each bone density phenotype via a mixed model with covariate adjustment. We identified quantitative trait loci (QTLs) for BMD phenotypes on chromosomes 2, 9, 10, and 13 meeting a conservative genomewide empiric significance threshold (false discovery rate [FDR] = 5%; p < 3 × 10−6). Importantly, most QTLs were localized to very small genomic regions (1–3 megabases [Mb]), allowing us to identify a narrow set of potential candidate genes including both novel genes and genes previously shown to have roles in skeletal development and homeostasis. © 2014 American Society for Bone and Mineral Research.
Cortical Bone Assessed With Clinical Computed Tomography at the Proximal Femur
Authors: Johannesdottir Fjola , Turmezei Tom , Poole Kenneth ES
Published: February 2014

Hip fractures are the most serious of all fragility fractures in older people of both sexes. Trips, stumbles, and falls result in fractures of the femoral neck or trochanter, and the incidence of these two common fractures is increasing worldwide as populations age. Although clinical risk factors and chance are important in causation, the ability of a femur to resist fracture also depends on the size and spatial distribution of the bone, its intrinsic material properties, and the loads applied. Over the past two decades, clinical quantitative computed tomography (QCT) studies of living volunteers have provided insight into how the femur changes with advancing age to leave older men and women at increased risk of hip fractures. In this review, we focus on patterns of cortical bone loss associated with hip fracture, age-related changes in cortical bone, and the effects of drugs used to treat osteoporosis. There are several methodologies available to measure cortical bone in vivo using QCT. Most techniques quantify bone density (g/cm3), mass (g), and thickness (mm) in selected, predefined or “traditional” regions of interest such as the “femoral neck” or “total hip” region. A recent alternative approach termed “computational anatomy,” uses parametric methods to identify systematic differences, before displaying statistically significant regions as color-scaled maps of density, mass, or thickness on or within a representative femur model. This review will highlight discoveries made using both traditional and computational anatomy methods, focusing on cortical bone of the proximal femur. © 2014 American Society for Bone and Mineral Research.
Endotracheal tube biofilm and ventilator‐associated pneumonia with mechanical ventilation
Authors: De Souza Paula Regina , De Andrade Denise , Cabral Danielle Bezerra , Watanabe Evandro
Published: February 2014

Objective: To analyze biofilm on internal and external surfaces of endotracheal tubes after their use in critical care patients, and to produce evidence of association between use of the tube, presence of biofilm, and the occurrence of pneumonia. Methods: This was a clinical study performed at the Intensive Care Unit of an emergency hospital in the interior of São Paulo state, Brazil. Data collection involved 30 endotracheal tubes used on adult patients for a period of ≥48 h of mechanical ventilation for scanning electron microscopy. Results: Analysis of the biofilm on the 30 tubes by scanning electron microscopy showed various abiotic and biotic structures, predominately on the internal surface, such as: fibrin network, erythrocytes, leukocytes, cocci, bacilli, and molds, among others. The intubation period of the endotracheal tube for ≥8 days represented one of the risk factors for ventilator‐associated pneumonia (RR 7.41, P < 0.001). Conclusions: The presence of the endotracheal tube permits microbial colonization, overall contributing to the development of biofilm and the occurrence of pneumonia. Microsc. Res. Tech. 77:305–312, 2014. © 2014 Wiley Periodicals, Inc.
A first Glimpse at the genome of the Baikalian amphipod Eulimnogammarus verrucosus
Authors: Rivarola‐Duarte Lorena , Otto Christian , Jühling Frank , Schreiber Stephan , Bedulina Daria , Jakob Lena , Gurkov Anton , Axenov‐Gribanov Denis , Sahyoun Abdullah H. , Lucassen Magnus , Hackermüller Jörg , Hoffmann Steve , Sartoris Franz , Pörtner Hans‐Otto , Timofeyev Maxim , Luckenbach Till , Stadler Peter F.
Published: February 2014

Eulimnogammarus verrucosus is an amphipod endemic to the unique ecosystem of Lake Baikal and serves as an emerging model in ecotoxicological studies. We report here on a survey sequencing of its genome as a first step to establish sequence resources for this species. From a single lane of paired‐end sequencing data, we estimated the genome size as nearly 10 Gb and we obtained an overview of the repeat content. At least two‐thirds of the genome are non‐unique DNA, and a third of the genomic DNA is composed of just five families of repetitive elements, including low‐complexity sequences. Attempts to use off‐the‐shelf assembly tools failed on the available low‐coverage data both before and after removal of highly repetitive components. Using a seed‐based approach we nevertheless assembled short contigs covering 33 pre‐microRNAs and the homeodomain‐containing exon of nine Hox genes. The absence of clear evidence for paralogs implies that a genome duplication did not contribute to the large genome size. We furthermore report the assembly of the mitochondrial genome using a new, guided “crystallization” procedure. The initial results presented here set the stage for a more complete sequencing and analysis of this large genome. J. Exp. Zool. (Mol. Dev. Evol.) 322B: 177–189, 2014. © 2014 Wiley Periodicals, Inc.
New frontiers in the evolution of fin development
Authors: Freitas Renata , Gómez‐Skarmeta José Luis , Rodrigues Pedro Nuno
Published: February 2014

The locomotory appendages of vertebrates have undergone significant changes during evolution, which likely promoted a wide range of adaptive strategies. These appendages first evolved as unpaired finfolds in the dorsal midline of early chordates, more than 500 million years ago. Later on, during vertebrates' radiation, two sets of locomotory appendages emerged, developing from both sides of the latero‐ventral body wall. The morphology of these paired fins in fishes at different phylogenetic positions suggests an evolutionary tendency for increasing elaboration of the endoskeleton and concomitant reduction of the distal dermoskeleton. This evolutionary process culminated with the origin of limbs in the lineages leading to tetrapods. The developmental programs responsible for the evolution of vertebrate appendages have been a major topic for evolutionary developmental biology recently. Gene expression comparisons performed in chordates explored how these mechanisms were transferred from a midline to latero‐ventral position. On another front, gene function assays have begun to test classical hypotheses concerning the transition from fish fins to tetrapod limbs. In this review, we highlight these recent findings on the evolution of vertebrate fin development. First, we discuss new perspectives on the transition from midline to paired appendages focus on (i) origin and molecular regionalization of the lateral plate mesoderm and (ii) novel ectodermic competency zones for fin induction. Next, we review recent work exploring how tetrapod limbs evolved from fish fins, considering (i) molecular and structural changes in the distal ectoderm of fins and (ii) modulation of 5′HoxD transcription during fin endoskeleton development. J. Exp. Zool. (Mol. Dev. Evol.) 322B: 540–552, 2014. © 2014 Wiley Periodicals, Inc.
Volume analyzer SYNAPSE VINCENT for liver analysis
Authors: Ohshima Shunsuke
Published: February 2014

In recent years, there has been an active movement to ensure the greater safety of actual surgeries, by simulating it preoperatively with the use of three‐dimensional image visualization technologies. Along with this movement, the Ministry of Health, Labour and Welfare has named “Image‐supported navigation in hepatectomy” as part of advanced medical techniques. This method aims to improve the safety during a surgery by calculating the volume of the liver dominated by each blood vessel or simulating, prior to surgery, the volume of resection zone or the remaining liver volume. These calculations and simulations are carried out using the three‐dimensional images produced by extractions of the liver, vascular and tumor regions from the computed tomography images, which were collected using the tomography apparatus prior to hepatectomy. In order to facilitate the achievement of such preoperative simulations, the volume analyzer SYNAPSE VINCENT (VINCENT, hereafter) by Fujifilm, in its Liver Analysis Application, comes equipped with unique features. This paper will introduce the technologies behind those unique features and provide a direction for future research and developments.
Usefulness of multi‐3‐dimensional computed tomograms fused with multiplanar reconstruction images and peroral cholangioscopy findings in hilar cholangiocarcinoma
Authors: Nagakawa Yuichi , Kasuya Kazuhiko , Bunso Kyo , Hosokawa Yuichi , Kuwabara Hiroshi , Nakagima Tetsushi , Osakabe Hiroaki , Tsuchiya Takayoshi , Itoi Takao , Tsuchida Akihiko
Published: February 2014

Multiplanar reconstruction (MPR) images are used for assessing horizontal and vertical extent of hilar cholangiocarcinoma, while peroral cholangioscopy (POCS) is used for diagnosing ductal spread and mapping biopsy. We fused conventional 3‐dimensional computed tomography (3DCT) with MPR images and POCS findings for preoperative assessment of cholangiocarcinoma. The extent of cancer was assessed using MPR images, which were plotted and fused onto 3DCT cholangiography. In addition, the results of mapping biopsy performed under POCS were marked on virtual endoscopic imaging and transferred onto a 3DCT image. Once an angiographic CT image was fused, a multi‐3DCT image was created. The incision line was determined based on these images. Multi‐3DCT images were created for 13 patients with hilar cholangiocarcinoma. Of 10 patients who underwent POCS, superficial spread was observed in two. Resection was performed in 12 patients. In two cases, the cut end of the intrahepatic bile duct was positive, resulting in 83.3% diagnostic accuracy for horizontal spread. In all patients, the estimated number of bile ducts was the same as the number of the actual resections. R0 resection was achieved in 10 patients (83.3%). Multi‐3DCT imaging proved useful in diagnosing longitudinal ductal spread of hilar cholangiocarcinoma.
Intra‐host diversity and evolution of hepatitis C virus endemic to Côte d'Ivoire
Authors: Forbi Joseph C. , Campo David S. , Purdy Michael A. , Dimitrova Zoya E. , Skums Pavel , Xia Guo‐liang , Punkova Lili T. , Ganova‐Raeva Lilia M. , Vaughan Gilberto , Ben‐Ayed Yousr , Switzer William M. , Khudyakov Yury E.
Published: February 2014

Hepatitis C virus (HCV) infection presents an important, but underappreciated public health problem in Africa. In Côte d'Ivoire, very little is known about the molecular dynamics of HCV infection. Plasma samples (n = 608) from pregnant women collected in 1995 from Côte d'Ivoire were analyzed in this study. Only 18 specimens (∼3%) were found to be HCV PCR‐positive. Phylogenetic analysis of the HCV NS5b sequences showed that the HCV variants belong to genotype 1 (HCV1) (n = 12, 67%) and genotype 2 (HCV2) (n = 6, 33%), with a maximum genetic diversity among HCV variants in each genotype being 20.7% and 24.0%, respectively. Although all HCV2 variants were genetically distant from each other, six HCV1 variants formed two tight sub‐clusters belonging to HCV1a and HCV1b. Analysis of molecular variance (AMOVA) showed that the genetic structure of HCV isolates from West Africa with Côte d'Ivoire included were significantly different from Central African strains (P = 0.0001). Examination of intra‐host viral populations using next‐generation sequencing of the HCV HVR1 showed a significant variation in intra‐host genetic diversity among infected individuals, with some strains composed of sub‐populations as distant from each other as viral populations from different hosts. Collectively, the results indicate a complex HCV evolution in Côte d'Ivoire, similar to the rest of West Africa, and suggest a unique HCV epidemic history in the country. J. Med. Virol. 86:765‒771, 2014. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.
Model order reduction applied to the numerical study of electrical motor based on POD method taking into account rotation movement
Authors: Henneron T. , Clénet S.
Published: February 2014

In order to reduce the computation time and the memory resources required to solve an electromagnetic field problem, model order reduction approaches can be applied to reduce the size of the linear equation system obtained after discretisation. In the literature, the POD is widely used in engineering. In this paper, we propose to apply the POD in the case of a finite element problem accounting for the movement. The efficiency of this method is evaluated by considering an electrical motor and by comparing with the full model in terms of computational time and accuracy. Copyright © 2014 John Wiley & Sons, Ltd.
The use of synoptic climatology with general circulation model output over New Zealand
Authors: Parsons Simon , McDonald Adrian J. , Renwick James A.
Published: February 2014

A cluster analysis‐based synoptic classification scheme, known as the Kidson types, was applied to reanalyses and Coupled Model Inter‐comparison Project phase 3 (CMIP3) general circulation model (GCM) output over New Zealand to identify the potential for future changes in regional circulation. Results indicate that a number of GCM 20th century control runs reproduce the type frequencies observed in reanalysis data. Application to future scenario runs for the periods 2046–2065 and 2081–2100 displays little variation in the annual frequency of the synoptic types relative to the 20th century, especially when uncertainty associated with the model ensemble is considered. This is surprising in the context of previous work on possible future movements in jet position and subsequent impacts on weather patterns. A sensitivity analysis that mimics the movement of the jet position was performed, revealing that the annual type frequencies are relatively insensitive to change. To determine whether this is a problem with the synoptic typing scheme, a correlation‐based classification technique was also used, but showed similar results. This work highlights issues with applying synoptic classification schemes to GCM output and indicates that if such schemes are to be used they should be designed and tested with this application in mind.
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

This 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

The 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

Various 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

An 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

Despite 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

Healthy, 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 < R2 < 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

Ultrasonic 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

Background

The 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.

Methods

Retrospective 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.

Results

Thirty 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.

Conclusions

Both 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.
Simultaneous determination of trace migration of phthalate esters in honey and royal jelly by GC–MS
Authors: Zhou Jinhui , Qi Yitao , Wu Hongmei , Diao Qingyun , Tian Feifei , Li Yi
Published: February 2014

A simple, rapid, and reliable liquid–liquid extraction coupled to GC–MS method was developed and validated for the quantification of 22 phthalate esters (PAEs) in honey and royal jelly. Instrument parameters for GC–MS were tested to obtain the satisfactory separation between 22 PAEs with high sensitivity. The extraction procedure was optimized in order to achieve the best recovery. The following criteria were used to validate the developed method: linearity, LOD, lower LOQ, precision, accuracy, matrix effect and carry‐over. Correlation coefficients were >0.999 by applying the linear regression model based on the least‐squares method with a weighting factor (1/x). The intra‐ and interday precision were within 12.7% in terms of RSD, and the accuracy was within −11.8% in terms of relative error. The mean extraction recoveries ranged between 80.1 and 110.9% for honey and royal jelly. No significant matrix effect and carry‐over for PAEs were observed for the analysis of honey and royal jelly samples. A total of 20 real samples were analyzed for a mini‐survey using the developed method. Seven PAEs in honey samples and five PAEs in royal jelly samples were found, indicating potential contamination with several PAEs.
In‐syringe‐assisted dispersive liquid–liquid microextraction coupled to gas chromatography with mass spectrometry for the determination of six phthalates in water samples
Authors: Clavijo Sabrina , del Rosario Brunetto María , Cerdà Víctor
Published: February 2014

A fully automated method for the determination of six phthalates in environmental water samples is described. It is based in the novel sample preparation concept of in‐syringe dispersive liquid–liquid microextraction, coupled as a front end to GC–MS, enabling the integration of the extraction steps and sample injection in an instrumental setup that is easy to operate. Dispersion was achieved by aspiration of the organic (extractant and disperser) and the aqueous phase into the syringe very rapidly. The denser‐than‐water organic droplets released in the extraction step, were accumulated at the head of the syringe, where the sedimented fraction was transferred to a rotary micro‐volume injection valve where finally was introduced by an air stream into the injector of the GC through a stainless‐steel tubing used as interface. Factors affecting the microextraction efficiency were optimized using multivariate optimization. Figures of merit of the proposed method were evaluated under optimal conditions, achieving a detection limit in the range of 0.03–0.10 μg/L, while the RSD% value was below 5% (n = 5). A good linearity (0.9956 ≥ r2 ≥ 0.9844) and a broad linear working range (0.5–120 μg/L) were obtained. The method exhibited enrichment factors and recoveries, ranging from 14.11–16.39 and 88–102%, respectively.
Rapid LC‐MS‐based metabolomics method to study the Fusarium infection of barley
Authors: Cajka Tomas , Vaclavikova Marta , Dzuman Zbynek , Vaclavik Lukas , Ovesna Jaroslava , Hajslova Jana
Published: February 2014

Ultra high performance liquid chromatography with quadrupole/time‐of‐flight mass spectrometry was applied to evaluate the potential of nontarget metabolomic fingerprinting in order to distinguish Fusarium‐infected and control barley samples. First, the sample extraction and instrumental conditions were optimized to obtain the broadest possible representation of polar/medium‐polar compounds occurring in extracts obtained from barley grain samples. Next, metabolomic fingerprints of extracts obtained from nine barley varieties were acquired under ESI conditions in both positive and negative mode. Each variety of barley was tested in two variants: artificially infected by Fusarium culmorum at the beginning of heading and a control group (no infection). In addition, the dynamics of barley infection development was monitored using this approach. The experimental data were statistically evaluated by principal component analysis, hierarchical clustering analysis, and orthogonal partial least‐squares discriminant analysis. The differentiation of barley in response to F. culmorum infection was feasible using this metabolomics‐based method. Analysis in positive mode provided a higher number of molecular features as compared to that performed under negative mode setting. However, the analysis in negative mode permitted the detection of deoxynivalenol and deoxynivalenol‐3‐glucoside considered as resistance‐indicator metabolites in barley.