bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simulating the spatial distribution of clay layer occurrence depth in alluvial soils with a Markov chain geostatistical approach
Authors: Li Weidong , Zhang Chuanrong 
Published: March 2009

AbstractThe spatial distribution information of clay layer occurrence depth (CLOD), particularly the spatial distribution maps of occurrence of clay layers at depths less than a certain threshold, in alluvial soils is crucial to designing appropriate plans and measures for precision agriculture and environmental management in alluvial plains. Markov chain geostatistics (MCG), which was proposed recently for simulating categorical spatial variables, can objectively decrease spatial uncertainty and consequently increase prediction accuracy in simulated results by using nonlinear estimators and incorporating various interclass relationships. In this paper, a MCG method was suggested to simulate the CLOD in a meso‐scale alluvial soil area by encoding the continuous variable with several threshold values into binary variables (for single thresholds) or a multi‐class variable (for all thresholds being considered together). Related optimal prediction maps, realization maps, and occurrence probability maps for all of these indicator‐coded variables were generated. The simulated results displayed the spatial distribution characteristics of CLOD within different soil depths in the study area, which are not only helpful to understanding the spatial heterogeneity of clay layers in alluvial soils but also providing valuable quantitative information for precision agricultural management and environmental study. The study indicated that MCG could be a powerful method for simulating discretized continuous spatial variables. Copyright © 2009 John Wiley & Sons, Ltd.
An accurate gradient and Hessian reconstruction method for cell‐centered finite volume discretizations on general unstructured grids
Authors: Betchen Lee J. , Straatman Anthony G. 
Published: March 2009

AbstractIn this paper, a novel reconstruction of the gradient and Hessian tensors on an arbitrary unstructured grid, developed for implementation in a cell‐centered finite volume framework, is presented. The reconstruction, based on the application of Gauss' theorem, provides a fully second‐order accurate estimate of the gradient, along with a first‐order estimate of the Hessian tensor. The reconstruction is implemented through the construction of coefficient matrices for the gradient components and independent components of the Hessian tensor, resulting in a linear system for the gradient and Hessian fields, which may be solved to an arbitrary precision by employing one of the many methods available for the efficient inversion of large sparse matrices. Numerical experiments are conducted to demonstrate the accuracy, robustness, and computational efficiency of the reconstruction by comparison with other common methods. Copyright © 2009 John Wiley & Sons, Ltd.
Linear quadratic regulation for systems with time‐varying delay
Authors: Zhang Huanshui , Xie Lihua , Wang Wei 
Published: March 2009

AbstractIn this paper we study the linear quadratic regulation (LQR) problem for discrete‐time systems with time‐varying delay in the control input channel. We assume that the time‐varying delay is of a known upper bound, then the LQR problem is transformed into the optimal control problem for systems with multiple input channels, each of which has single constant delay. The optimal controller is derived by establishing a duality between the LQR and a smoothing estimation for an associated system with a multiple delayed measurement. Copyright © 2009 John Wiley & Sons, Ltd.
Discrete state observability of hybrid systems
Authors: Di Benedetto Maria D. , Di Gennaro Stefano , D'Innocenzo Alessandro 
Published: March 2009

AbstractWe propose a novel definition of observability, motivated by safety critical applications, given with respect to a subset ofcriticaldiscrete states that model unsafe or unallowed behaviors. For the class of discrete event systems, we address the problem in the setting of formal (regular) languages and propose a novel observability verification algorithm. For the class of switching systems, we characterize the minimal set of extra output information to be provided by the continuous signals in order to satisfy observability conditions, and propose a milder observability notion that allows a bounded delay in state observation. For the class of hidden Markov models, we analyze decidability and complexity of the verification problem. Copyright © 2009 John Wiley & Sons, Ltd.
Decentralized adaptive fuzzy sliding mode control for reconfigurable modular manipulators
Authors: Zhu Mingchao , Li Yuanchun 
Published: March 2009

AbstractA stable decentralized adaptive fuzzy sliding mode control scheme is proposed for reconfigurable modular manipulators to satisfy the concept of modular software. For the development of the decentralized control, the dynamics of reconfigurable modular manipulators is represented as a set of interconnected subsystems. A first‐order Takagi–Sugeno fuzzy logic system is introduced to approximate the unknown dynamics of subsystem by using adaptive algorithm. The effect of interconnection term and fuzzy approximation error is removed by employing an adaptive sliding mode controller. All adaptive algorithms in the subsystem controller are derived from the sense of Lyapunov stability analysis, so that resulting closed‐loop system is stable and the trajectory tracking performance is guaranteed. The simulation results are presented to show the effectiveness of the proposed decentralized control scheme. Copyright © 2009 John Wiley & Sons, Ltd.
Gene Targeting in a HUES Line of Human Embryonic Stem Cells Via Electroporation
Authors: Ruby Katherine M. , Zheng Binhai 
Published: March 2009

Abstract
Genetic modification is critical for achieving the full potential of human embryonic stem (ES) cells as a tool for therapeutic development and for basic research. Targeted modifications in human ES cells have met with limited success because of the unique culture conditions for many human ES cell lines. The HUES lines of human ES cells were developed for ease of manipulation and are gaining increased utility in stem cell research. We tested conditions for gene targeting via electroporation in the HUES-9 human ES cell line and demonstrate here successful gene targeting at the gene encoding Fezf2 (also known as Fezl), a transcription factor involved in corticospinal neuron development. With a targeting strategy involving positive and negative selection that is applicable to all genes, we observed a gene targeting frequency of ∼1.5% for Fezf2, a gene not expressed in human ES cells. We found that conditions developed for gene targeting in mouse ES cells can be readily adapted to HUES cells with few key modifications. HUES-9 cells exhibit an intrinsically high efficiency of clonal expansion and sustain electroporation-based gene targeting procedures without any significant loss of pluripotency marker expression or karyotypic stability. Thus, human ES cell lines adapted for enzymatic passage and efficient clonal expansion can be highly amenable to genetic modifications, which will facilitate their application in basic science and clinical development.
Disclosure of potential conflicts of interest is found at the end of this article.
Bioluminescence Imaging of Olig2-Neural Stem Cells Reveals Improved Engraftment in a Demyelination Mouse Model
Authors: Sher Falak , van Dam Go , Boddeke Erik , Copray Sjef 
Published: March 2009

Abstract
A major issue in the potential application of neural stem cell (NSC)-based cell replacement therapy for demyelinating diseases is the question of the survival, functional behavior, and stability of implanted NSC-derived oligodendrocyte precursor cells (OPCs) over an extended period. To address this issue, we employed bioluminescence imaging (BLI) as a noninvasive longitudinal in vivo monitoring technique and followed the fate of NSCs isolated from luciferase–green fluorescent protein–actin transgenic mice after stereotactic implantation in the demyelinated corpus callosum of cuprizone-fed mice. We compared normal NSCs with NSCs that were primed to become OPCs by the induction of Olig2 overexpression (Olig2-NSCs). BLI, validated by immunohistochemistry, revealed that, after a steep cell loss after implantation during the first 3 weeks, approximately 10% of the Olig2-NSCs stably survived for 2 months after implantation, in contrast to &lt;1% of the normal NSCs. Immunohistochemistry, at the light and electron microscopic levels, revealed that the majority of the surviving Olig2-NSCs had differentiated into an oligodendrocytic cell lineage and contributed to remyelination of axons in the corpus callosum. The number of axons remyelinated by the implanted cells, however, was a small fraction of the total number of axons remyelinated by endogenous oligodendrocytes. Apparently, most of the implanted NSCs did not survive the transition into an inappropriate non-neurogenic niche, compressed by surrounding host tissue, in hostile, inflammatory conditions created by activated microglia. Only the ones that managed to differentiate rapidly into a mature neural cell type and become functionally integrated survived.
Disclosure of potential conflicts of interest is found at the end of this article.
Tubulin heterodimers remain functional for one cell cycle after the inactivation of tubulin‐folding cofactor D in fission yeast cells
Authors: Fedyanina Olga S. , Book Adam J. , Grishchuk Ekaterina L. 
Published: March 2009

AbstractTubulin‐folding cofactor D plays a major role in the formation of functional tubulin heterodimers, the subunits of microtubules (MTs) that are essential for cell division. Previous work has suggested that, in Schizosaccharomyces pombe, cofactor D function is required during G1 or S phases of the cell cycle, and when it fails to function due to the temperature‐sensitive mutation alp1‐t1, cells are unable to segregate their chromosomes in the subsequent mitosis. Here we report that another mutation in the cofactor D gene, alp1‐1315, causes failures in either the first or second mitosis in cells synchronized in G1 or G2 phases, respectively. Other results, however, suggest that the kinetics of viability loss in these mutants does not depend on progression through the cell cycle. When cofactor D function is perturbed in cells blocked in G2, cytoplasmic MTs appear normal for 2–3 h but thereafter they disintegrate quickly, so that only a few short MTs remain. These residual MTs are, however, stably maintained, suggesting that they do not require active cofactor D function. The abrupt disassembly of MT cytoskeleton at restrictive temperature in non‐cycling cofactor D mutant cells strongly suggests that the life‐span of folded tubulin dimers might be downregulated. Indeed, this period is significantly shorter than the previously determined dissociation time of bovine tubulins in vitro. The death of mutant cells occurs inevitably after 2–3 h at restrictive temperature in the following mitosis, and is explained by the idea that MT structures formed in the absence of cofactor D cannot support normal cell division. Copyright © 2009 John Wiley & Sons, Ltd.
Inferior meatus endoscopy and directed treatment for epiphora: Early experience with a novel approach
Authors: Rogers G. Aaron , Murchison Ann P. , Wojno Ted H. , DelGaudio John M. 
Published: March 2009

ObjectivesEpiphora results from obstruction along the nasolacrimal (NL) system. The inferior meatus (IM) is not routinely evaluated. IM pathology is common in patients with epiphora, allowing surgery to be directed at the IM.MethodsRetrospective review of patients referred for epiphora. Patients underwent office endoscopy of the IM. Patients with identifiable pathology underwent intervention directed at the IM.ResultsSeventeen patients were evaluated, four with bilateral epiphora. Two had no IM disease, and one with pathology refused surgery. The remaining 14 (18 sides) had IM pathology. Two patients were successfully treated in the office. Twelve patients underwent surgery (16 sides). Three NLD orifices were obstructed by a cyst, and the remaining 13 by hypertrophied soft tissue at the level of the NLD orifice. Thirteen of 14 sides with distal NLD pathology had resolution or dramatic improvement and patent NL ducts with IM treatment alone. Obstruction extending proximal to Hasner's valve was found in four NL systems, and three developed recurrent epiphora. Median follow‐up was 9 months.ConclusionsIM endoscopy identified pathology in most constant epiphora patients in this study. Pathology at the distal NL system portends a better outcome, whereas extension to the proximal NL duct had poorer outcome.
Gamma tubulin: A promising indicator of recurrence in squamous cell carcinoma of the larynx
Authors: Syed Mohammed Iqbal , Syed Sheeba , Minty Fay , Harrower Steven , Singh Jatinder , Chin Andy , McLellan Douglas R. , Parkinson Eric K. , Clark Louise J. 
Published: March 2009

ObjectiveCentrosome amplification as detected by gamma tubulin (GT) immunostaining is associated with genetic instability and tumor aggressiveness. We assessed GT for its ability to predict recurrence of squamous cell carcinoma of the larynx (SCCL).Study DesignCase series with chart review.Materials and MethodsFive micron sections of 35 archival SCCL samples were subjected to antigen retrieval and immunostaining with antibody to GT. The keratin antibody CK5 served as a positive control for antigen retrieval, and tonsillar tissue was used as a negative control.ResultsOf the 35 tumors analyzed, 22 were associated with recurrence(R) and 13 were not (NR). Fourteen of the 22 R tumors, but 0 of 13 of the NR tumours had a GT staining score of 2+ or 3+ (P < 0.0002). GT was also related to recurrence in node‐negative tumors (P < 0.006) but was unrelated to T stage (P = 0.726).ConclusionsGT staining appears to be a better predictor of tumor recurrence than T stage and also predicts recurrence in N0 tumors.
Host range and distribution of fruit-infesting pestiferous fruit flies (Diptera, Tephritidae) in selected areas of Central Tanzania
Authors: Mwatawala M.W. , De Meyer M. , Makundi R.H. , Maerere A.P. 
Published: March 2009

AbstractThe host range of major fruit fly pests in Central Tanzania was evaluated from October 2004 to October 2006. Samples of 48 potential hosts were collected and incubated for fruit fly emergence.Bactrocera invadenswas the dominant species in incidence expressed as the ratio of infested to total number samples collected, as well as infestation rate, expressed as number of flies emerging per unit weight. Eight new host fruits are reported. Infestation by native pests, such asCeratitis capitataandC. cosyra, was minor compared toB. invadens.Ceratitis rosawas the dominant species in temperate fruits, and Cucurbitaceae were mainly infested byBactrocera cucurbitae, a specialized cucurbit feeder. Among commercial fruits, high infestation incidences were observed in mango and guava, but they decreased throughout the fruiting season. Low infestation rates were observed in allCitrusspecies and in avocado, indicating these fruits as poor hosts for the studied fruit fly pests in this region. Widespread availability and abundance of fruit species studied here ensures year-round breeding ofB. invadens. Seasonal infestation differs, with mango being the most important host in October to January, while guava being important from February to August. Tropical almond showed very high incidence and infestation rate forB. invadensand might act as an important reservoir host, bridging the fruiting seasons of mango and guava. Soursop acts as an important host forC. cosyraafter the mango season.Ceratitis capitatais a pest of minor importance of the commercial fruits studied in this region.
Constitutive telomere length and gastric cancer risk: Case‐control analysis in Chinese Han population
Authors: Liu Xiaonan , Bao Guoqiang , Huo Tingting , Wang Zizhong , He Xianli , Dong Guanglong 
Published: March 2009

The shortening of telomeres may result in chromosome instability and thus promote tumorigenesis. Previous studies have demonstrated clear involvement of telomere shortening in the carcinogenesis of several malignancies. However, the association between constitutive telomere shortening and gastric cancer development has yet to be established. Therefore, in the present study, we measured average telomere length using quantitative real‐time PCR in peripheral blood lymphocytes from a gastric cancer (GC) case‐control study consisting of 396 cases and 378 controls. The results showed that GC patients had significantly shorter average telomere length than matched controls (mean ± SD 0.89 ± 0.19 vs 1.06 ± 0.25, P < 0.001). We further categorized telomere length using the 50% value in the controls as a cut‐off point and assessed the association between telomere length and GC risk using multivariate logistic regression analysis. We found that short telomere length was associated with a significantly increased GC risk (adjusted odds ratio = 2.14, 95% confidence interval = 1.52–2.93). Quartile stratification revealed a dose–response relationship between telomere shortening and GC risk (P for trend < 0.001). Stratified analysis showed that sex, age, and alcohol drinking, but not smoking and Helicobacter pylori infection, seem to have a modulating effect on the average telomere length in both cases and controls. We also found that telomere shortening and smoking had a significant joint effect on GC risk. Collectively, our findings provide the first evidence linking the short telomere length in peripheral blood lymphocytes to elevated GC risk, which warrants further investigation in other populations. (Cancer Sci 2009; 100: 1300–1305)
Refined localization of the Escherichia coli F4ab/F4ac receptor locus on pig chromosome 13
Authors: Joller D. , Jørgensen C. B. , Bertschinger H. U. , Python P. , Edfors I. , Cirera S. , Archibald A. L. , Bürgi E. , Karlskov‐Mortensen P. , Andersson L. , Fredholm M. , Vögeli P. 
Published: March 2009

SummaryDiarrhoea in newborn and weaned pigs caused by enterotoxigenic Escherichia coli (ETEC) expressing F4 fimbriae leads to considerable losses in pig production. In this study, we refined the mapping of the receptor locus for ETEC F4ab/F4ac adhesion (F4bcR) by joint analysis of Nordic and Swiss data. A total of 236 pigs from a Nordic experimental herd, 331 pigs from a Swiss experimental herd and 143 pigs from the Swiss performing station were used for linkage analysis. Genotyping data of six known microsatellite markers, two newly developed markers (MUC4gt and HSA125gt) and an intronic SNP in MUC4 (MUC4‐8227) were used to create the linkage map. The region for F4bcR was refined to the interval SW207–S0075 on pig chromosome 13. The most probable position of F4bcR was in the SW207–MUC4 region. The order of six markers was supported by physical mapping on the BAC fingerprint contig from the Wellcome Trust Sanger Institute. Thus, the region for F4bcR could be reduced from 26 to 14 Mb.
Gene‐expression profiles in human nasal polyp tissues and identification of genetic susceptibility in aspirin‐intolerant asthma
Authors: Sekigawa T. , Tajima A. , Hasegawa T. , Hasegawa Y. , Inoue H. , Sano Y. , Matsune S. , Kurono Y. , Inoue I. 
Published: March 2009

SummaryBackground
Aspirin‐intolerant asthma (AIA) is a subtype of asthma induced by non‐steroidal anti‐inflammatory drugs and characterized by an aggressive mucosal inflammation of the lower airway (asthma) and the upper airways (rhinitis and nasal polyp). The lower airway lesion and the nasal polyp in AIA are postulated to have common pathogenic features involving aspirin sensitivity that would be reflected in the gene expression profile of AIA polyps.Objective
This study was conducted to clarify the pathogenesis of AIA using gene expression analysis in nasal polyps, and identify genetic susceptibilities underlying AIA in a case–control association study.Methods
Global gene expression of nasal polyps from nine AIA patients was examined using microarray technology in comparison with nasal polyps from five eosinophilic sinusitis (ES) patients, a related disease lacking aspirin sensitivity. Based on the AIA‐specific gene expression profile of nasal polyp, candidate genes for AIA susceptibility were selected and screened by a case–control design of 219 AIA patients, 374 non‐asthmatic control (CTR), and 282 aspirin‐tolerant asthmatic (ATA) subjects.Results
One hundred and forty‐three elevated and three decreased genes were identified as AIA‐specific genes that were enriched in immune response according to Gene Ontology analysis. In addition, a k‐means‐based algorithm was applied to cluster the genes, and a subclass characteristic of AIA comprising 18 genes that were also enriched in immune response was identified. By examining the allelic associations of single nucleotide polymorphisms (SNPs) of AIA candidate genes relevant to an immune response with AIA, two SNPs, one each of INDO and IL1R2, showed significant associations with AIA (P=0.011 and 0.026 after Bonferroni's correction, respectively, in AIA vs. CTR). In AIA–ATA association analysis, modest associations of the two SNPs with AIA were observed.Conclusion
These results indicate that INDO and IL1R2, which were identified from gene expression analyses of nasal polyps in AIA, represent susceptibility genes for AIA.
Modulation of in vivo and in vitro cytokine production over the course of pregnancy in allergic and non‐allergic mothers
Authors: Breckler Liza Anne , Hale Jasmine , Jung Wiebke , Westcott Lauren , Dunstan Janet A. , Thornton Catherine A. , Prescott Susan L. 
Published: March 2009

Breckler LA, Hale J, Jung W, Westcott L, Dunstan JA, Thornton CA, Prescott SL. Modulation of in vivo and in vitro cytokine production over the course of pregnancy in allergic and non‐allergic mothers. Pediatr Allergy Immunol 2010: 21: 14–21. © 2009 The Authors Journal compilation © 2009 Blackwell MunksgaardCytokines secreted during pregnancy may influence immune development of the foetus. This study aimed to determine if maternal allergy alters patterns of systemic cytokine production throughout and after pregnancy. Maternal plasma cytokines and allergen‐specific production of interleukin (IL)‐10, IL‐13 and interferon (IFN)‐γ were measured in allergic (n = 63) and non‐allergic (n = 70) pregnant women who had a full set of sequential peripheral blood samples collected at 20‐, 30‐, 36‐wk gestation and 6‐wk post‐partum. Maternal allergy was strictly defined by both allergen sensitization and doctor‐diagnosed asthma, eczema or rhinitis. IL‐13 responses to allergen were higher for allergic mothers at all time‐points (20 wk: p < 0.001; 30 wk: p = 0.001; 36 wk: p < 0.001; post‐partum: p < 0.001). For the non‐allergic group, IL‐13 levels to house dust mite decreased from 20‐ to 36‐wk gestation (Friedman anova p = 0.012) and were significantly lower at 36 wk compared with post‐partum (p = 0.002). In contrast, IL‐13 production by allergic mothers did not change from 20 wk through to post‐partum. For both allergic and non‐allergic mothers, in vitro IFN‐γ production was lower at all pregnancy time‐points compared with post‐partum levels. Allergic women had an increased propensity for peripheral blood allergen‐specific T helper‐2 responses during pregnancy, and failed to downregulate these responses in comparison with non‐allergic women. This may be a factor that contributes to the increased risk of atopy in infants born to allergic mothers.