bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of poly(3‐hydroxybutyrate‐co‐4‐hydroxybutyrate‐co‐3‐hydroxyhexanoate) on growth and osteogenic differentiation of human bone marrow‐derived mesenchymal stem cells
Authors: Wei Xing , Hu Ya‐Jun , Xie Wen‐Peng , Lin Ruo‐Ling , Chen Guo‐Qiang 
Published: July 2008

AbstractAs a new member of polyhydroxyalkanoate (PHA) family, the novel polyester poly(3‐hydroxybutyrate‐co‐4‐hydroxybutyrate‐co‐3‐hydroxyhexanoate) (P(3HB‐4HB‐3HHx)) was produced by recombinant Aeromonas hydrophila 4AK4 and used for the first time to test its biocompatibility. It was shown that P(3HB‐4HB‐3HHx) had higher hydrophobicity, surface energy, and rougher surface than the well‐studied polymers poly(L‐lactic acid) (PLA) and poly(3‐hydroxybutyrate‐co‐3‐hydroxyhexanoate) (PHBHHx). Human mesenchymal stem cells (MSCs) attached better on P(3HB‐4HB‐3HHx) film than on tissue culture plates (TCPs), PLA film, and PHBHHx film. MSC proliferation on P(3HB‐4HB‐3HHx) film was 126% higher than that on TCPs, 84% higher than that on PHBHHx film, and 312% higher than that on PLA film (p < 0.01). P(3HB‐4HB‐3HHx) also supported osteogenic differentiation of MSCs. Previous studies found that all PHA materials tested were either less than or equal to TCPs for supporting cell growth. Among all PHA materials tested, P(3HB‐4HB‐3HHx) was the only PHA material to significantly promote cell proliferation compared with TCPs. P(3HB‐4HB‐3HHx) could be exploited for applications in bone tissue engineering. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res 2008
Best practices in community‐based prevention for youth substance reduction: towards strengths‐based positive development policy
Authors: Cheon Jeong Woong 
Published: July 2008

AbstractSubstance use among youth remains a major public health and safety concern. One fundamental way to address youth substance use prevention is to keep young people on a positive trajectory by engaging them in positive activities from early years of their childhood. In this article, the author offers a best practice analysis of systematic review about 12 selected community‐based preventions, and proposes policy changes towards incorporating a strengths perspective. A substantive, methodological, and value‐based critical analysis of the strongly effective preventions was conducted. A strengths‐based positive youth development perspective is specified as one feasible needed improvement and subsequent policy changes in the school district as well as in the local, state, and federal levels are proposed along with the suggestion of a mandated community youth participation strategy. © 2008 Wiley Periodicals, Inc.
QSPR study on GC relative retention time of organic pesticides on different chromatographic columns
Authors: Hu Ruzhu , Yin Chunsheng , Wang Yang , Lu Chunhui , Ge Tiefei 
Published: July 2008

AbstractIn the present study, Lu index and distance‐based atom type topological index (DAI) previously developed in our team, were introduced and combined with molecular electronegativity χep to characterize quantitative structure‐property relationship of GC relative retention time (RRT) for several types of structurally diverse organic pesticides on the four kinds of chromatographic columns. Using multiple linear regression technique, four several‐variable models are obtained with the estimations correlation coefficient (R2) being between 0.9655 and 0.9285, and the correlation coefficient (R2cv) in the leave‐one‐out cross‐validation procedure are between 0.9560 and 0.9143, respectively. The results in this study indicate that the three topological indices Lu index, DAI, and molecular electronegativity χep can predict the gas chromatographic RRT of organic pesticides with diverse hetero‐atoms.
Tailoring orthogonal proteomic routines to understand protein separation during ion exchange chromatography
Authors: Cabrera Rosa , Zhelyazkova Petya , Galvis Leonardo , Fernandez‐Lahore Marcelo 
Published: July 2008

AbstractSurface charge, molecular weight, and folding state are known to influence protein chromatographic behaviour onto ion exchangers. Experimentally, information related to such factors can be gathered via 2‐DE methods. The application of 2‐D PAGE under denaturing/reducing conditions was already shown to reveal separation trends within a large protein population from cell extracts. However, ion‐exchange chromatography normally runs under native conditions. A tailored protocol consisting in a first separation based on IEF on ImmobilineTM strips under native conditions followed by a second dimension SDS‐PAGE run was adopted. The chromatographic versus electrophoretic separation behaviours of two model proteins, thaumatin (TAU) and BSA, were compared to better understand which proteomic routine would be better suited to anticipate IEX chromatographic separations. It was observed that the information contained in the pI value obtained with the adapted 2‐DE protocol showed better correlation with the IEX chromatographic behaviour. On the other hand, chromatographic separations performed in the presence of urea as a denaturant have demonstrated the potential influence of hydrodynamic radius/conformation on protein separation. Moreover, the information provided by such 2‐D system correlated well with the chromatographic behaviour of an additional set of pure proteins. An initial prediction of protein ion‐exchange chromatographic behaviour could be possible utilizing an experimental approach based on 2‐DE running under milder chemical conditions. This technique provides information that more closely resembles the separation behaviour observed with a complex biotechnological feedstock.
Evaluation of the coupling between ultra performance liquid chromatography and evaporative light scattering detector for selected phytochemical applications
Authors: Russo Rossana , Guillarme Davy , Rudaz Serge , Bicchi Carlo , Veuthey Jean‐Luc 
Published: July 2008

AbstractFast analysis in LC can be performed with sub‐2 μm particles at very high pressures (up to 1000 bar) known as ultra performance LC (UPLC). With this configuration, it is possible to obtain fast and/or highly efficient separations compared to conventional LC. For the analysis of compounds without chromophores, the evaporative light scattering detector (ELSD) is an attractive alternative because of its quasi‐universality, versatility, low‐cost and good sensitivity. The UPLC–ELSD was investigated in terms of sensitivity and apparent efficiency, with a conventional ELSD instrument, for two types of commercially available nebulisers, using different mobile phase flow rates and column ids. Results were finally compared with the UPLC–UV configuration. Three applications with phytochemical compounds were selected to highlight the potential of this approach (i.e. the isocratic separations of artemisinin and its derivatives, of calystegines and the gradient separation of several tropane alkaloids). Depending on the used column length, baseline separations were obtained in 3–10 min, with an average apparent efficiency ranging from 7000 to 30 000 plates.
Regioregular Phenyl and Phenoxy Substituted Polythiophenes for Bulk Heterojunction Solar Cells
Authors: Ouhib F. , Dupuis G. , Hiorns R.C. , Khoukh A. , Bailly S. , Martinez H. , de Bettignies R. , Desbrières J. , Dagron‐Lartigau C. 
Published: July 2008

AbstractSummary: Poly[3‐(4‐octylphenyl) thiophene] (POPT) and poly[3‐(4‐octylphenoxy) thiophene] (POPOT) with high head‐to‐tail regioregularities have been synthesised and photovoltaic properties have been investigated. POPT‐blend‐PCBM exhibits an interesting behaviour in bulk heterojunction whereas POPOT presents poor photovoltaic performances. UV‐visible absorption and AFM images of the blends are presented to explain these results.
Comparison of Operating Mechanisms for the Poly(N‐vinylcarbazole) Based Non‐Volatile Memory Devices
Authors: Choi Jin‐Sik , Suh Dong Hack 
Published: July 2008

AbstractSummary: The organic non‐volatile memory devices (NVMs) based on poly(N‐vinylcarbazole) (PVK) with the different structures and compositions were fabricated and evaluated. The resistance states in the devices were controlled by the external electric field and exhibited the distinctive properties; the device with a single PVK layer was a write‐once read‐many‐times memory by the field induced filament as a conduction path and its memory properties depended on the PVK thickness, the PVK/Al/PVK structured device was operated by a space charge limited current model and was sensitive to preparing condition of the internal Al layer, and the device performances with the PVK based charge transfer complex depended on the composition of the CT materials and the surface condition of the bottom electrode.
Polymer Composites with Plasmonic Metal Nanoparticles
Authors: Dammer Ondřej , Vlčková Blanka , Podhájecká Klára , Procházka Marek , Pfleger Jiří 
Published: July 2008

AbstractSummary: A two‐phase method has been adapted for the preparation of polymer composites consisting of regioregular poly(3‐octylthiophene‐2,5‐diyl) and Au or Ag nanoparticles. This work compares optical and morphological properties of nanocomposites formed by mixing metal organosols and polymer solution (type I composites) with nanocomposites formed by in‐situ reduction in polymer solutions (type II composites). Both types contained very small metal nanoparticles (1–10 nm). Interestingly, more than ten‐fold enhancement of Raman scattering of the polymer by the electromagnetic (EM) mechanism of SERS (surface‐enhanced Raman scattering) resulted from the coupling of the polymer with plasmonic Au nanoparticles into a nanocomposite system.
Estimation and extrapolation of optimal treatment and testing strategies
Authors: Robins James , Orellana Liliana , Rotnitzky Andrea 
Published: July 2008

AbstractWe review recent developments in the estimation of an optimal treatment strategy or regime from longitudinal data collected in an observational study. We also propose novel methods for using the data obtained from an observational database in one health‐care system to determine the optimal treatment regime for biologically similar subjects in a second health‐care system when, for cultural, logistical, or financial reasons, the two health‐care systems differ (and will continue to differ) in the frequency of, and reasons for, both laboratory tests and physician visits. Finally, we propose a novel method for estimating the optimal timing of expensive and/or painful diagnostic or prognostic tests. Diagnostic or prognostic tests are only useful in so far as they help a physician to determine the optimal dosing strategy, by providing information on both the current health state and the prognosis of a patient because, in contrast to drug therapies, these tests have no direct causal effect on disease progression. Our new method explicitly incorporates this no direct effect restriction. Copyright © 2008 John Wiley & Sons, Ltd.
Retardation in somatosensory cortex development induced by postnatal BrdU treatment in mice
Authors: Béldi Melinda , Takács József , Bárdos György , Világi Ildikó 
Published: July 2008

AbstractCerebral dysgeneses are in the background of several neurological and mental disturbances. The aim of the present study was to investigate structural and activity changes following disturbed postnatal neuronal development in mice. Newborn C57Bl6 mice were exposed to 5‐bromo‐2′‐deoxyuridine (BrdU: daily 50 μg/g body weight) during a period between postnatal days P0–P5 or P0–P11, respectively, and neuronal malformation and malfunctioning of somatosensory (barrel field) cortex was analyzed in adolescent animals. Alterations in histological architecture of interneuronal and glial elements were studied and correlated with electrophysiological modifications. Between P30 and P35 days litters underwent ex vivo electrophysiological experiments to examine the changes in basic excitability and in synaptic efficacy. Parallel immunohistochemistry was performed to detect BrdU, GABA and GFAP.There were no BrdU immunopositive cell nuclei in control animals, but marked staining was observed in both BrdU treated groups. Lessening in the number of GABAergic neurons was observed in the treated groups. GFAP immunohistochemical analysis has shown an increased number of activated astroglial cells in treated animals. Reduction of the number of GABAergic neurons was observed in the treated groups. Electrophysiological recordings on cortical slices showed increased excitability in the treated groups.
Expression of Rho GTPases Rho‐A and Rac1 in the adult and developing gerbil cerebellum
Authors: Richard Vaea , Dulon Didier , Hafidi Aziz 
Published: July 2008

AbstractRho GTPases proteins are essential for cytoskeletal reorganization and play important roles in the development of neuronal dendrites and axons. Several studies have implicated two members of the Rho GTPase family Rho‐A and Rac1 activities in the neuronal polarization and the formation of axons and dendrites. In order to correlate cellular expressions of Rho‐A and Rac1 with neuronal polarity (axons versus dendrite formation) in the central nervous system, the cerebellum and immunochemical techniques have been chosen. In the adult cerebellar cortex differential pattern of distribution between Rho‐A and Rac1 was observed. While Rac1 expression was restricted to Purkinje cell (somata, dendrites and axons), Rho‐A was ubiquitously distributed within the cerebellar cortex. Rac1 was localized in the Purkinje cell dendritic arborization (largest and tiny dendrites) and in their axons. This pattern of distribution was also observed during the postnatal development and followed the dendritic morphogenesis of Purkinje cell. Rho‐A was highly expressed in the adult Purkinje cells somata, in cells of the granular layer, in glia within the white matter and in axons. Intense staining was observed in Bergmann glia cell bodies and processes. In the developing cerebellum, Rho‐A was highly present in cells of the external and internal granule layers and in the Purkinje cell layer. Bergmann glia cell bodies and processes had the most intense staining during the development. The present study reveals a high expression of Rac1 and Rho‐A during Purkinje cell neurites outgrowth period which occurred after birth in the cerebellum. In addition Rho‐A is highly expressed in granule cell progenitor cells present in the external granular layer and therefore may play an important role in granule cell progenitor migration.
Tectonic control of mafic intrusions in the Tastau volcanoplutonic complex (eastern Kazakhstan)
Authors: Dokukina K.A. , Vladimirov V.G. 
Published: July 2008

Abstract
We discovered unusual very small (2 to 70 cm) mafic bodies intruded into metamorphosed Early Carboniferous sandstone and shale in the Late Paleozoic Tastau volcanoplutonic complex (Char shear zone, eastern Kazakhstan). The small intrusions possibly emplaced during shearing when sediments experienced cataclasis and ensuing viscosity decrease. The shear rate was comparable to that in historic crustal earthquakes. Rapid shear motion concurrent with magmatism caused fragmentation of the injecting low-viscosity melt and its dispersal in globular and other bodies along linear breccia zones. The origin of the intrusions is explained in a tectonic model.
Check Your Data Freedom: A Taxonomy to Assess Life Science Database Openness
Authors: Dulong de Rosnay Melanie 
Published: July 2008

AbstractMolecular biology data are subject to terms of use that vary widely between databases and curating institutions. This research presents a taxonomy of contractual and technical restrictions applicable to databases in life science. It builds upon research led by Science Commons demonstrating why open data and the freedom to integrate facilitates innovation and how this openness can be achieved. The taxonomy describes technical and legal restrictions applicable to life science databases, and its metadata have been used to assess terms of use of databases hosted by Life Science Resource Name (LSRN) Schema. While a few public domain policies are standardized, most terms of use are not harmonized, difficult to understand and impose controls that prevent others from effectively reusing data. Identifying a small number of restrictions allows one to quickly appreciate which databases are open. A checklist for data openness is proposed in order to assist database curators who wish to make their data more open to make sure they do so.
A ward without walls? District nurses’ perceptions of their workload management priorities and job satisfaction
Authors: Stuart Elaine Haycock , Jarvis Alison , Daniel Katie 
Published: July 2008

Aim.  To explore district nurses’ workload management, job satisfaction and the challenges they face.Background.  This paper reports qualitative findings from a qualitative and quantitative study to identify a district nursing perspective on use of time, challenges and work satisfaction. District nursing is under increasing pressure because of the increasing shift to care in the community, early hospital discharge and changes in demography with an ageing population and more people with chronic illnesses.Design.  Qualitive.Method.  The study took place in one Scottish Health Board and data were collected in February and March 2005. The qualitative approach involved a total of 31 district nurses and senior managers in focus group discussions or individual interviews.Results.  Three main themes were identified: (1) the priorities of district nurses and their views on work unrelated to ‘hands on’ clinical care, (2) aspects of district nursing considered stressful and (3) district nurses’ job satisfaction.Conclusion.  District nurses and managers agree that caring work with patients is the priority for the service and provides job satisfaction. Many nurses feel overwhelmed by their workload and have little control over the admission of patients to their caseload; they are mainly demand led and therefore reactive care providers. A culture of long hours has developed as district nurses struggle to meet the needs of patients. Feeling devalued lowers satisfaction and Agenda for Change is perceived as de‐valuing the skills of community nurses.Relevance to clinical practice.  More clerical support is required so district nurses can deliver care to patients. District nurses can better represent their workload and how it is managed through expressing the nature of assessing risk and caring for patients as opposed to defining patients care needs by medical diagnoses. Extending the hours of the full district nursing service would benefit patients and staff.
Transcriptional regulation of plant senescence: from functional genomics to systems biology
Authors: Breeze E. , Harrison E. , Page T. , Warner N. , Shen C. , Zhang C. , Buchanan‐Wollaston V. 
Published: July 2008

AbstractLeaf senescence is an active process that involves the increased expression of many hundreds of genes. Many putative transcription factors show enhanced transcription during leaf senescence in Arabidopsis and functional analysis of these should help to indicate their role in controlling gene expression during leaf senescence. In this paper, we describe the analysis of knockout insertion mutants in two different senescence‐enhanced genes, one encodes a heat shock transcription factor and the other a zinc finger protein. Plants mutated in these genes show accelerated leaf senescence and reduced tolerance to drought stress, indicating that expression of these genes during senescence has a protective role to maintain viability during this essential developmental process. Analysis of gene expression changes in both mutants compared to the wild‐type plants indicates an increased rate of senescence but does not show clearly the pathway that is dependent on these genes for expression. The complexities of signalling networks in plant stress and the plasticity of plant responses mean that the direct consequences of mutation are very difficult to define. The usefulness of this type of approach to address the burning question of how senescence is regulated is discussed, and an alternative approach aimed at a more global analysis of gene regulation using systems biology methods is described.
Transcription factors regulating leaf senescence in Arabidopsis thaliana
Authors: Balazadeh S. , Riaño‐Pachón D. M. , Mueller‐Roeber B. 
Published: July 2008

AbstractSenescence is a highly regulated process, eventually leading to cell and tissue disintegration: a physiological process associated with nutrient (e.g. nitrogen) redistribution from leaves to reproductive organs. Senescence is not observed in young leaves, indicating that repressors efficiently act to suppress cell degradation during early leaf development and/or that senescence activators are switched on when a leaf ages. Thus, massive regulatory network re‐wiring likely constitutes an important component of the pre‐senescence process. Transcription factors (TFs) have been shown to be central elements of such regulatory networks. Here, we used quantitative real‐time polymerase chain reaction (qRT‐PCR) analysis to study the expression of 1880 TF genes during pre‐senescence and early‐senescence stages of leaf development, using Arabidopsis thaliana as a model. We show that the expression of 185 TF genes changes when leaves develop from half to fully expanded leaves and finally enter partial senescence. Our analysis identified 41 TF genes that were gradually up‐regulated as leaves progressed through these developmental stages. We also identified 144 TF genes that were down‐regulated during senescence. A considerable number of the senescence‐regulated TF genes were found to respond to abiotic stress, and salt stress appeared to be the major factor controlling their expression. Our data indicate a peculiar fine‐tuning of developmental shifts during late‐leaf development that is controlled by TFs.
Genetics: how the UKPDS contributed to determining the genetic landscape of Type 2 diabetes
Authors: Gloyn A. L. , McCarthy M. I. 
Published: July 2008

AbstractThe identification and functional characterisation of genetic variants that either cause or predispose to diabetes is a major focus of biomedical research. The molecular basis is now known for the majority of monogenic forms of diabetes arising from pancreatic β‐cell dysfunction; however finding the genetic variants underlying susceptibility to Type 2 diabetes (T2DM) has been a greater technical, statistical and biological challenge. The advent of biology–agnostic approaches made possible by the improved arsenal of research platforms and genetic tools available has increased the number of known T2DM genes dramatically and provided important insights into the pathophysiology of T2DM. Over the past 18 months, the list of T2DM susceptibility genes has grown from three to close to 20, illustrating the substantial progress which has been made. These recent milestones have not only illustrated the limited knowledge we have of the pancreatic β‐cell, but have also reinforced our belief in the involvement of common genetic variants in the genes involved in monogenic forms of diabetes in the susceptibility to T2DM and have clearly shown a primary role for pancreatic β‐cell dysfunction in T2DM. Both of these concepts were explored in the early work of the UK Prospective Diabetes Study (UKPDS) genetics research groups.