bluuebunny/crossref_metadata_2025_split huggingface dataset:
Canadian RCM projected changes to high flows for Québec watersheds using regional frequency analysis
Authors: Clavet‐Gaumont J. , Sushama L. , Khaliq M. N. , Huziy O. , Roy R. 
Published: December 2012

ABSTRACTInformation related to changes in streamflow characteristics is important in the management and future planning of various water resources‐related projects in the context of a changing climate. In this study, projected changes to selected return levels of high flows for 21 watersheds, located mainly in the Québec province of Canada, are assessed following regional frequency analysis (RFA). This assessment is based on a ten‐member ensemble of Canadian regional climate model (CRCM) transient climate change simulations, of which five correspond to current 1970–1999 period and the remaining five are the matching simulations for the future 2041–2070 period. This is the first comprehensive study on high‐flow characteristics for the entire 21 watersheds in the context of a changing climate using the RFA approach, which allows better estimation of return levels, particularly for higher return periods, than single site/grid‐cell based analysis. Validation of the European Centre for Medium‐Range Weather Forecasts Re‐Analysis‐driven CRCM simulated 5‐, 10‐, 30‐ and 50‐year return levels against those observed at selected gauging stations suggests a general overestimation, with average differences of 9 and 12% (3–5%) for the 5‐ and 10‐year (30‐ and 50‐year) return levels, respectively. Results of ensemble averaged projected changes to regional return levels show increases for most of the watersheds. In particular, changes to 5‐ and 10‐year (compared to 30‐ and 50‐year) regional return levels are found to be statistically significant more often for northern watersheds compared to the rest. An evaluation of confidence in projected changes to selected regional return levels, based on five current/future period simulation pairs, reveal a higher level of confidence for northern watersheds. When regional level projected changes are developed at the CRCM grid‐cell level, a pattern similar to that for regional level changes is noticed, though with slightly increased range of changes.
Matrix metalloproteinase‐12 is associated with overall survival in Chinese patients with gastric cancer
Authors: Zheng Jianyong , Chu Dake , Wang Desheng , Zhu Yongsheng , Zhang Xiaoyin , Ji Gang , Zhao Haihong , Wu Guosheng , Du Jianjun , Zhao Qingchuan 
Published: December 2012

AbstractBackground and ObjectivesMatrix metalloproteinase‐12 (MMP‐12) plays an important role in invasion and metastasis of human solid tumor cells. This study aimed to investigate the association of MMP‐12 with overall survival in human gastric cancer.MethodsGastric cancer and adjacent normal tissue specimens were collected from 165 patients who had not received neoadjuvant chemotherapy. MMP‐12 expression was determined by immunohistochemical staining, and the results were analyzed statistically in relation to the overall survival of the patients.ResultsMMP‐12 expression was increased in gastric cancer compared with that observed in normal tissues. Increased MMP‐12 expression was associated with tumor invasion, lymph node metastasis, distant metastasis, and TNM stage. No correlations were detected between MMP‐12 expression and age, sex, differentiation status, tumor site, or Lauren classification. Moreover, patients with MMP‐12 positive gastric cancer tended to have worse overall survival compared with those patients without MMP‐12 expression.ConclusionsThe study results showed that increased expression of MMP‐12 was associated with tumor progression in gastric cancer. It also provided the first evidence for MMP‐12 expression in gastric cancer as an independent prognostic factor. J. Surg. Oncol. 2013;107:746–751. © 2012 Wiley Periodicals, Inc.
Investigation of the Polymerization Behavior and Regioselectivity of Fluorene Diamine‐Based Benzoxazines
Authors: Wang Jun , He Xuan‐Yu , Liu Jun‐Ting , Liu Wen‐Bin , Yang Lei 
Published: December 2012

AbstractA series of fluorene diamine‐based benzoxazine monomers are prepared from the reaction of 9,9‐bis‐(4‐aminophenyl)‐fluorene with paraformaldehyde and unsubstituted or substituted phenols. Unsubstituted and substituted phenol‐based benzoxazines show different polymerization behaviors and give polymers with different thermal properties. The ortho and para positions on the phenol for benzoxazines based on phenol and m‐cresol could concurrently participate in the crosslinking reaction during thermal ring‐opening polymerization to form Mannich and methylene bridges at high temperature. The glass‐transition temperature and thermal stability of the resulting polymers are much higher than those of other substituted phenol‐based polybenzoxazines and bisphenol fluorene‐based polybenzoxazines.
Cross‐talk between microRNAs, nuclear factor E2‐related factor 2, and heme oxygenase‐1 in ochratoxin A‐induced toxic effects in renal proximal tubular epithelial cells
Authors: Stachurska Anna , Ciesla Maciej , Kozakowska Magdalena , Wolffram Siegfried , Boesch‐Saadatmandi Christine , Rimbach Gerald , Jozkowicz Alicja , Dulak Jozef , Loboda Agnieszka 
Published: December 2012

ScopeOchratoxin A (OTA) is a mycotoxin exhibiting nephrotoxic and potential carcinogenic activity. We investigated the cross‐talk between microRNAs, nuclear factor E2‐related factor 2 (Nrf2), and heme oxygenase‐1 (HO‐1) in ochratoxin A‐mediated effects.Methods and resultsIn porcine renal proximal tubular cells, OTA increased expression of profibrotic transforming growth factors β (TGFβ) while concomitantly decreasing expression of Nrf2, HO‐1, and erythropoietin. Adenoviral overexpression of Nrf2 counteracted OTA‐mediated reduction in HO‐1 and erythropoietin expression and cell proliferation as well as increase in reactive oxygen species (ROS) generation and TGFβ expression. Additionally, inhibition of HO activity enhanced whereas adenoviral overexpression of HO‐1 reduced expression of TGFβ. Moreover, antioxidants, N‐acetyl‐cysteine and desferioxamine, prevented OTA‐mediated enhancement of ROS generation, and TGFβ expression. Finally, OTA modulated microRNA processing by upregulating LINeage protein 28 and DiGeorge syndrome critical region‐8, increasing the total pool of cellular microRNAs and elevating the expression of miR‐132 and miR‐200c. Inhibition of miR‐132 by specific antagomir restored the OTA‐driven reduction in Nrf2 expression. Moreover, anti‐miR‐132 and anti‐miR‐200c counteracted OTA‐mediated decrease in HO‐1 levels as well as increase in ROS production and TGFβ expression.ConclusionWe showed that attenuation of Nrf2 and HO‐1 expression through induction of miR‐132 and miR‐200c by OTA elevates ROS levels and profibrotic TGFβ expression.
Expression and localization of creatine kinase in the preimplantation embryo
Authors: Forsey Katherine E. , Ellis Peter J. , Sargent Carole A. , Sturmey Roger G. , Leese Henry J. 
Published: December 2012

AbstractCreatine Kinase (CK) catalyses the “creatine shuttle,” the reversible conversion of creatine phosphate to creatine with the liberation of ATP. This article examines the potential role of the creatine shuttle in the provision of ATP during mouse preimplantation embryo development. Using quantitative PCR, transcripts of four subunit isoforms of CK—CKM, CKB, CKMT1, and CKMT2—were detectable at all developmental stages, from the presumptive zygote to late blastocyst, but there was no obvious pattern in gene expression. By contrast, total CK biochemical activity, measured by a novel method, was relatively constant from the 2‐ to 8‐cell stage, before exhibiting a significant decrease in activity at the blastocyst stage. Immunocytochemical studies revealed a marked association of CKB with the mitotic spindle in 2‐ and 4‐cell mouse embryos, consistent with the proposition that the creatine shuttle plays a key role in local delivery of ATP during cytokinesis. Endogenous creatine was detected in the blastocyst at a level of 0.53 pmol/embryo. In conclusion, we believe that creatine phosphate can now be added to the list of potential sources of ATP during preimplantation development. Mol. Reprod. Dev. 80: 185–192, 2013. © 2013 Wiley Periodicals, Inc.
Monitoring bovine fetal fibroblast reprogramming utilizing a bovine NANOG promoter‐driven EGFP reporter system
Authors: Lei Lei , Li Lei , Du Fuliang , Chen Chien‐Hong , Wang Huayan , Keefer Carol L. 
Published: December 2012

AbstractNANOG is an essential transcription factor involved in the proliferation and maintenance of embryonic stem cells (ESC) and reprogramming of somatic cells to a pluripotent state. Oct4 and Nanog promoter‐driven enhanced green fluorescent protein (EGFP) reporters have been employed for establishing lines of induced pluripotent stem cells (iPSC) from mouse, human, and pig. In ruminants, including cattle, in which no fully validated ESC lines have been established, iPSC generated by reprogramming somatic cells to an ESC‐like state may prove useful in the production of genetically modified livestock. In this study, utility of the bovine NANOG reporter was tested for use with cattle. Seven proximal bovine NANOG promoter fragments of different size were fused to the LUC gene, and were tested in mouse ESC lines using a dual‐luciferase assay. Three of the bovine NANOG promoters, 315 bp (−134/+181), 446 bp (−265/+181), and 1,100 bp (−919/+181), were fused to a nuclear localized signal EGFP reporter gene. The fidelity of these constructs was analyzed by transfection into mouse ESC and bovine fetal fibroblasts (bFFs), and subsequent reprogramming of the bFF. Fusion of the transgenic bFF with human teratocarcinoma (NTERA2) cells induced nuclear expression of the EGFP reporter. Similarly, bFF‐derived somatic cell nuclear transfer (SCNT) embryos expressed EGFP in a stage‐ and location‐appropriate manner. Following reprogramming of transgenic bFFs for 10 days with an Oct4‐Sox2‐Klf4‐cMyc vector, iPSC expressed EGFP and alkaline phosphatase. These results indicate that NANOG reporters can be used to monitor nuclear reprogramming of bFFs and to distinguish cell allocation in SCNT‐derived embryos. Mol. Reprod. Dev. 80: 193–203, 2013. © 2013 Wiley Periodicals, Inc.
Topology optimization of structures using meshless density variable approximants
Authors: Luo Zhen , Zhang Nong , Wang Yu , Gao Wei 
Published: December 2012

SUMMARYThis paper proposes a new structural topology optimization method using a dual‐level point‐wise density approximant and the meshless Galerkin weak‐forms, totally based on a set of arbitrarily scattered field nodes to discretize the design domain. The moving least squares (MLS) method is used to construct shape functions with compactly supported weight functions, to achieve meshless approximations of system state equations. The MLS shape function with the zero‐order consistency will degenerate to the well‐known ‘Shepard function’, while the MLS shape function with the first‐order consistency refers to the widely studied ‘MLS shape function’. The Shepard function is then applied to construct a physically meaningful dual‐level density approximant, because of its non‐negative and range‐restricted properties. First, in terms of the original set of nodal density variables, this study develops a nonlocal nodal density approximant with enhanced smoothness by incorporating the Shepard function into the problem formulation. The density at any node can be evaluated according to the density variables located inside the influence domain of the current node. Second, in the numerical implementation, we present a point‐wise density interpolant via the Shepard function method. The density of any computational point is determined by the surrounding nodal densities within the influence domain of the concerned point. According to a set of generic design variables scattered at field nodes, an alternative solid isotropic material with penalization model is thus established through the proposed dual‐level density approximant. The Lagrangian multiplier method is included to enforce the essential boundary conditions because of the lack of the Kronecker delta function property of MLS meshless shape functions. Two benchmark numerical examples are employed to demonstrate the effectiveness of the proposed method, in particular its applicability in eliminating numerical instabilities. Copyright © 2012 John Wiley & Sons, Ltd.
Howard's algorithm in a phase‐field topology optimization approach
Authors: Wallin Mathias , Ristinmaa Matti 
Published: December 2012

SUMMARYThe topology optimization problem is formulated in a phase‐field approach. The solution procedure is based on the Allan–Cahn diffusion model where the conservation of volume is enforced by a global constraint. The functional defining the minimization problem is selected such that no penalization is imposed for full and void materials. Upper and lower bounds of the density function are enforced by infinite penalty at the bounds. A gradient term that introduces cost for boundaries and thereby regularizing the problem is also included in the objective functional. Conditions for stationarity of the functional are derived, and it is shown that the problem can be stated as a variational inequality or a max–min problem, both defining a double obstacle problem. The numerical examples used to demonstrate the method are solved using the FEM, whereas the double obstacle problem is solved using Howard's algorithm. Copyright © 2012 John Wiley & Sons, Ltd.
A two‐level method in space and time for the Navier‐Stokes equations
Authors: Liu Qingfang , Hou Yanren , Liu Qingchang 
Published: December 2012

AbstractA two‐level method in space and time for the time‐dependent Navier‐Stokes equations is considered in this article. The approximate solution uM∈HM is decomposed into the large eddy component v∈Hm(m < M) and the small eddy component w∈H. We obtain the large eddy component v by solving a standard Galerkin equation in a coarse‐level subspace Hm with a time step length k, whereas the small eddy component w is derived by solving a linear equation in an orthogonal complement subspace H with a time step length pk, where p is a positive integer. The analysis shows that our two‐level scheme has long‐time stability and can reach the same accuracy as the standard Galerkin method in fine‐level subspace HM for an appropriate configuration of p and m. Moreover, some numerical examples are provided to complement our theoretical analysis. © 2012 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2013
Some error estimates of finite volume element method for parabolic optimal control problems
Authors: Luo Xianbing , Chen Yanping , Huang Yunqing , Hou Tianliang 
Published: December 2012

SUMMARYIn this paper, the finite volume element method (FVEM) is applied to solve the distributed optimal control problems governed by parabolic equation. We use the method of variational discretization concept to approximate the problems. We consider a semi‐discrete and a fully discrete piecewise linear FVEMs. For the semi‐discrete method, the optimal order error estimates in continuous L ∞ (J; L2) and L ∞ (J; H1)‐norm are obtained; the suboptimal error estimates in continuous L ∞ (J; L ∞ )‐norm are also obtained. For the fully discrete method, the optimal order error estimates in discrete L2(J; L2) and L ∞ (J; L2)‐norm are derived. Numerical experiments are presented to test these theoretical results. Copyright © 2012 John Wiley & Sons, Ltd.
Synthesis and properties of networking waterborne polyurethane/silica nanocomposites by addition of poly(ester amine) dendrimer
Authors: Han Wensong 
Published: December 2012

AbstractThe second‐generation poly(ester amine) dendrimer was prepared by Michael addition reaction and esterification reaction at first. Then, a series of novel waterborne polyurethane (WPU)‐based composites were prepared by the addition of poly(ester amine) dendrimer into the WPU. The structures and the morphology of the WPU composites were measured with Fourier transform infrared spectrometer, scanning electron microscopy, and X‐ray diffraction. SEM images revealed that the nanosilica was well dispersed in the WPU matrix. The mechanical properties of the WPU composites were improved with the addition of poly (ester amine) dendrimer. The dynamic mechanical thermal analysis results showed that the WPU composites had higher glass transition temperature than that of pure WPU, especially after incorporation of poly(ester amine) dendrimer. This conclusion is in good agreement with the differential scanning calorimetry results. The thermal properties of the pure WPU and its composites were investigated by thermogravimetric analysis. The results showed that the initial decompose temperature began from about 250°C, and had a little increase when introducing poly(ester amine) dendrimer into the WPU matrix. POLYM. COMPOS., 2012. © 2013 Society of Plastics Engineers
Intergenerational transmission of educational attainment: Three levels of parent–child communication as mediators
Authors: Chi Liping 
Published: December 2012

AbstractAlthough the intergenerational transmission of educational attainment has been confirmed by many researchers, its mechanism still remains controversial. Parent–child communication has been regarded as one of the important mediators. The present study primarily aimed to examine the potentially mediating role of parent–child communication in the transmission of educational attainment, based on a sample of 366 Chinese fifth and sixth graders. Parent–child communication was measured against the three levels of the parents' communication ability, the quality of the father–child and mother–child communications, and the relation between the two dyadic communications. The results duplicated the positive effect of parents' educational attainment on children's academic achievement. Moreover, it was found that parents' communication ability alone played a mediating role, and that the three levels of parent–child communication constructed a “mediator chain” between the parents' educational attainment and the children's academic achievement. Finally, the intergenerational transmission of educational attainment in China and the mediating role of the three levels of parent–child communication were discussed.
Measuring adult Attention Deficit Hyperactivity Disorder using the Quantified Behavior Test Plus
Authors: Edebol Hanna , Helldin Lars , Norlander Torsten 
Published: December 2012

AbstractAttention Deficit Hyperactivity Disorder (ADHD) occurs in approximately 5% of the adult population and includes cardinal symptoms of hyperactivity, inattention, and impulsivity that may be difficult to identify with clinical routine methods. Continuous performance tests are objective measures of inattention and impulsivity that, combined with objective measures of motor activity, facilitate identification of ADHD among adults. The aim of the present study was to examine the sensitivity, specificity, and a composite measure of ADHD using objective measures of the ADHD‐cardinal symptoms in adult participants with ADHD and non‐ADHD normative participants. Cardinal symptoms were measured in 55 participants having ADHD, 202 non‐ADHD normative participants, as well as 84 ADHD normative participants using the Quantified Behavior Test Plus. This test measures inattention and impulsivity using a continuous performance test, and hyperactivity using a motion‐tracking system. A predictive variable for the detection of ADHD called Prediction of ADHD yielded 86% sensitivity and 83% specificity. A composite measure of ADHD cardinal symptoms was developed using a Weighed Core Symptoms scale that indicated the total amount of ADHD symptoms on a numeric scale from 0 to 100. The total amount of ADHD symptoms was measured on a scale and predicted with the categorical variable in a majority of the cases in the present study. Further studies are needed in order to confirm the results with regard to additional clinical and normative samples. Careful consideration of potential sex and diagnostic subtype differences are noteworthy aspects for future examinations of the new instruments.
Investigating differences in treatment effect estimates between propensity score matching and weighting: a demonstration using STAR*D trial data
Authors: Ellis Alan R. , Dusetzina Stacie B. , Hansen Richard A. , Gaynes Bradley N. , Farley Joel F. , Stürmer Til 
Published: December 2012

ABSTRACTPurposeThe choice of propensity score (PS) implementation influences treatment effect estimates not only because different methods estimate different quantities, but also because different estimators respond in different ways to phenomena such as treatment effect heterogeneity and limited availability of potential matches. Using effectiveness data, we describe lessons learned from sensitivity analyses with matched and weighted estimates.MethodsWith subsample data (N = 1292) from Sequenced Treatment Alternatives to Relieve Depression, a 2001–2004 effectiveness trial of depression treatments, we implemented PS matching and weighting to estimate the treatment effect in the treated and conducted multiple sensitivity analyses.ResultsMatching and weighting both balanced covariates but yielded different samples and treatment effect estimates (matched RR 1.00, 95% CI: 0.75–1.34; weighted RR 1.28, 95% CI: 0.97–1.69). In sensitivity analyses, as increasing numbers of observations at both ends of the PS distribution were excluded from the weighted analysis, weighted estimates approached the matched estimate (weighted RR 1.04, 95% CI 0.77–1.39 after excluding all observations below the 5th percentile of the treated and above the 95th percentile of the untreated). Treatment appeared to have benefits only in the highest and lowest PS strata.ConclusionsMatched and weighted estimates differed due to incomplete matching, sensitivity of weighted estimates to extreme observations, and possibly treatment effect heterogeneity. PS analysis requires identifying the population and treatment effect of interest, selecting an appropriate implementation method, and conducting and reporting sensitivity analyses. Weighted estimation especially should include sensitivity analyses relating to influential observations, such as those treated contrary to prediction. Copyright © 2012 John Wiley & Sons, Ltd.
Tracking control of high‐concentration photovoltaic systems for minimizing power losses
Authors: Kim Yong Sin , Kang Sung‐Mo , Winston Roland 
Published: December 2012

ABSTRACTThis paper presents three key factors that cause system mismatches and power losses in high‐concentration photovoltaic (HCPV) systems. The first factor is the I–V mismatch within a module, similar to the manufacturing mismatches in conventional photovoltaic modules. The second factor is the misalignments amongst modules, and the third factor is the tracking control. Unlike in the conventional photovoltaic systems, the second and the third factors in HCPV systems introduce larger electro‐optical mismatches due to narrow acceptance angles. We have developed a model to address these three factors. It allows an accurate estimation of power losses in HCPV systems, which enabled us to propose configurations to reduce power losses without adding additional electrical components to the system. Simulation results show that the power harvest can be increased as much as 8.5% for a system using open‐loop controls by simply increasing the number of strings at the time of calibration. Experimental test results are presented for validation. Copyright © 2012 John Wiley & Sons, Ltd.