bluuebunny/crossref_metadata_2025_split huggingface dataset:
Statistical process control in nursing research
Authors: Polit Denise F. , Chaboyer Wendy 
Published: November 2011

AbstractIn intervention studies in which randomization to groups is not possible, researchers typically use quasi‐experimental designs. Time series designs are strong quasi‐experimental designs but are seldom used, perhaps because of technical and analytic hurdles. Statistical process control (SPC) is an alternative analytic approach to testing hypotheses about intervention effects using data collected over time. SPC, like traditional statistical methods, is a tool for understanding variation and involves the construction of control charts that distinguish between normal, random fluctuations (common cause variation), and statistically significant special cause variation that can result from an innovation. The purpose of this article is to provide an overview of SPC and to illustrate its use in a study of a nursing practice improvement intervention. © 2011 Wiley Periodicals, Inc. Res Nurs Health 35:82–93, 2012
Acid‐modified carbon nanotubes distribution and mechanical enhancement in polystyrene/elastomer blends
Authors: Fan Xi , Wang Zhicheng , Wang Ke , Deng Hua , Chen Feng , Fu Qiang 
Published: November 2011

AbstractThe incorporation of carbon nanotubes (CNTs) is expected as an effective path for tailoring mechanical properties of polymer blends. In this study, acid‐modified multiwalled CNTs (A‐MWCNTs) were introduced into polystyrene/maleic anhydride‐g‐(styrene‐ethylene‐butadiene‐styrene) (PS/SEBS‐MA) blends. By altering the mass ratio of PS/SEBS‐MA from 80/20 to 60/40, the biphase structure of blend was changed from sea‐island‐like type to quasi co‐continuous structure, of different mechanical behaviors. In 80/20 mass ratio, the impact strength was improved while the tensile strength was unchanged with increasing A‐MWCNTs content, whereas a simultaneously toughening and strengthening effect was achieved for the compound with 60/40 mass ratio. Scanning electron microscopy, polarized light microscopy, dynamic mechanical analysis, and rheological measurements were carried out to detect the distribution of A‐MWCNTs in the blends. The results demonstrated as increasing the nanotube loading from 0 to 3 wt%, A‐MWCNTs might gradually migrate into continuous PS phase in 80/20 mass ratio, due to the low content of SEBS‐MA, while they were totally packed in SEBS‐MA region within the entire loading range used in 60/40 mass ratio due to its high content of SEBS‐MA. This study provides guidance on the design and preparation of high performance ternary polymer/elastomer/inorganic filler composites. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Anthrax toxin protective antigen—Insights into molecular switching from prepore to pore
Authors: Bann James G. 
Published: November 2011

AbstractThe protective antigen is a key component of the anthrax toxin, as it allows entry of the enzymatic components edema factor and lethal factor into the host cell, through the formation of a membrane spanning pore. This event is absolutely critical for the pathogenesis of anthrax, and although we have yet to understand the mechanism of pore formation, recent developments have provided key insights into how this process may occur. Based on the available data, a model is proposed for the kinetic steps for protective antigen conversion from prepore to pore. In this model, the driving force for pore formation is the formation of the phi (ϕ)‐clamp, a region that forms a leak‐free seal around the translocating polypeptide. Formation of the ϕ‐clamp elicits movements within the prepore that provide steric freedom for the subsequent conformational changes required to form the membrane spanning pore.
Global search for stable screw dislocation cores in III‐N semiconductors
Authors: Kraeusel S. , Hourahine B. 
Published: November 2011

AbstractThe promise of the broad range of direct band gaps of the {Al, Ga, In}N system is limited by the crystal quality of current material. As grown defect densities of InN, when compared with the more mature GaN, are extremely high and InN is strongly influenced by these defects. This is particularly important due to the unusual position of the charge neutrality level of InN, leading to both the well‐known surface charge accumulation and difficulties in p‐type doping. While impurities and native defects clearly impact on the bulk carrier density in InN, the effects of threading dislocations on the electrical properties are still in dispute. Issues such as whether the dislocation line is charged or contains dangling bonds remain open. We present the results of a global search for possible dislocation core reconstructions for a range of screw dislocations in wurtzite III‐N material, utilizing empirical Stillinger–Weber inter‐atomic potentials. In addition, we investigate a wide range of non‐stoichiometric core structures.
High carrier concentration in high Al‐composition AlGaN‐channnel HEMTs
Authors: Hashimoto Shin , Akita Katsushi , Yamamoto Yoshiyuki , Ueno Masaki , Nakamura Takao , Yafune Norimasa , Sakuno Keiichi , Tokuda Hirokuni , Kuzuhara Masaaki , Takeda Kenichiro , Iwaya Motoaki , Amano Hiroshi 
Published: November 2011

AbstractHigh Al‐composition (Al = 51%) and low Al‐composition (Al = 20%) AlGaN‐channel high‐electron‐mobility transistors (HEMTs) on AlN layers with very high carrier concentration were demonstrated. In two types of HEMTs, 2‐dimensional electron gases (2DEG) were clearly observed and peak carrier concentration and sheet carrier concentration were approximately 1020 cm‐3 and higher than 2 × 1013 cm‐2, respectively. From the X‐ray diffraction (XRD) measurements, it was observed that the AlGaN channel layers on the AlN layers were partially relaxed and the degree of relaxation decreased with increasing Al‐composition of AlGaN channel layers. Therefore the misfit dislocations in the high Al‐composition HEMTs were considered to be lower than those in the low Al‐composition HEMTs. Furthermore, it was revealed that very high Al‐composition of AlGaN barrier layers can be grown coherently on the AlGaN channel layers in consequence of the partly relaxation of the AlGaN channel layers, which of lattice constants of a‐axis were smaller than that of fully relaxed AlGaN channel layers. Therefore very high carrier concentration of 2DEG can be obtained in spite of the high Al‐composition of AlGaN channel layers. We considered that this high carrier concentration of 2DEG was necessary to demonstrate high Al‐composition AlGaN‐channel HEMTs. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Arrays of 850 nm photodiodes and vertical cavity surface emitting lasers for 25 to 40 Gbit/s optical interconnects
Authors: Lott J. A. , Payusov A. S. , Blokhin S. A. , Moser P. , Ledentsov N. N. , Bimberg D. 
Published: November 2011

AbstractWe report the design and characterization of arrays of compact, energy efficient, multi‐ and single‐mode GaAs‐based 850 nm vertical cavity surface emitting lasers (VCSELs) and complementary p‐i‐n photodiodes (PDs) for 25 to 40 Gb/s optical interconnection applications in computing and data communications. Using foundry service epitaxial growth and processing we obtain over 50k operational devices from each 76.2 mm‐diameter wafer. Using randomly selected on‐wafer‐probed, individually‐probed, and packaged VCSEL and PD dice for single‐channel link tests we consistently achieve record error‐free operation (defined as a bit error ratio (BER) of less than 1x10‐12) at 25 Gbit/s over up to 500 m of OM3 multimode optical fiber. We use our high speed VCSELs to characterize our high speed PDs and vice versa, and achieve open optical eye diagrams at up to 40 Gbit/s (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
IT‐supported innovation management in the automotive supplier industry to drive idea generation and leverage innovation
Authors: Neumann Martin , Riel Andreas , Brissaud Daniel 
Published: November 2011

SUMMARYInnovative product development is highly dependent on new product ideas and product information. This especially applies to companies that obtain their competitive advantages by technological lead like the automotive supplier industry. Innovation management in these industries has to focus on an efficient idea generation, implementation and capitalisation, and on technology tracking. This paper gives an insight into the industry‐sector‐specific characteristics of innovation management within the automotive supplier industry, and outlines a basic scheme of an innovation management system that aims at improving the existing innovation management at the automotive supplier Kolbenschmidt Pierburg AG. Copyright © 2011 John Wiley & Sons, Ltd.
Morphogen gradients in development: from form to function
Authors: Christian Jan L. 
Published: November 2011

AbstractMorphogens are substances that establish a graded distribution and elicit distinct cellular responses in a dose‐dependent manner. They function to provide individual cells within a field with positional information, which is interpreted to give rise to spatial patterns. Morphogens can consist of intracellular factors that set up a concentration gradient by diffusion in the cytoplasm. More commonly, morphogens comprise secreted proteins that form an extracellular gradient across a field of cells. Experimental studies and computational analyses have provided support for a number of diverse strategies by which extracellular morphogen gradients are formed. These include free diffusion in the extracellular space, restricted diffusion aided by interactions with heparan sulfate proteoglycans, transport on lipid‐containing carriers or transport aided by soluble binding partners. More specialized modes of transport have also been postulated such as transcytosis, in which repeated rounds of secretion, endocytosis, and intracellular trafficking move morphogens through cells rather than around them, or cytonemes, which consist of filopodial extensions from signal‐receiving cells that are hypothesized to reach out to morphogen‐sending cells. Once the gradient has formed, cells must distinguish small differences in morphogen concentration and store this information even after the gradient has dissipated. This is often achieved by translating ligand concentration into a proportional increase in numbers of activated cell surface receptors that are internalized and continue to signal from endosomal compartments. Ultimately, this leads to activation of one or a few transcription factors that transduce this information into qualitatively distinct gene responses inside the nucleus. WIREs Dev Biol 2012, 1:3–15. doi: 10.1002/wdev.2This article is categorized under:

Establishment of Spatial and Temporal Patterns > Gradients
Comparisons of the embryonic development of Drosophila, Nasonia, and Tribolium
Authors: Lynch Jeremy A. , El‐Sherif Ezzat , Brown Susan J. 
Published: November 2011

AbstractStudying the embryogenesis of diverse insect species is crucial to understanding insect evolution. Here, we review current advances in understanding the development of two emerging model organisms: the wasp Nasonia vitripennis and the beetle Tribolium castaneum in comparison with the well‐studied fruit fly Drosophila melanogaster. Although Nasonia represents the most basally branching order of holometabolous insects, it employs a derived long germband mode of embryogenesis, more like that of Drosophila, whereas Tribolium undergoes an intermediate germband mode of embryogenesis, which is more similar to the ancestral mechanism. Comparing the embryonic development and genetic regulation of early patterning events in these three insects has given invaluable insights into insect evolution. The similar mode of embryogenesis of Drosophila and Nasonia is reflected in their reliance on maternal morphogenetic gradients. However, they employ different genes as maternal factors, reflecting the evolutionary distance separating them. Tribolium, on the other hand, relies heavily on self‐regulatory mechanisms other than maternal cues, reflecting its sequential nature of segmentation and the need for reiterated patterning. WIREs Dev Biol 2012, 1:16–39. doi: 10.1002/wdev.3This article is categorized under:

Comparative Development and Evolution > Model Systems
Comparative Development and Evolution > Body Plan Evolution
Salivary gland organogenesis
Authors: Knosp Wendy M. , Knox Sarah M. , Hoffman Matthew P. 
Published: November 2011

AbstractOur understanding of vertebrate salivary gland organogenesis has been largely informed by the study of the developing mouse submandibular gland (SMG), which will be the major focus of this review. The mouse SMG has been historically used as a model system to study epithelial–mesenchymal interactions, growth factor–extracellular matrix (ECM) interactions, and branching morphogenesis. SMG organogenesis involves interactions between a variety of cell types and their stem/progenitor cells, including the epithelial, neuronal, and mesenchymal cells, and their ECM microenvironment, or niche. Here, we will review recent literature that provides conceptual advances in understanding the molecular mechanisms of salivary gland development. We will describe SMG organogenesis, introduce the model systems used to study development, and outline the key signaling pathways and cellular processes involved. We will also review recent research focusing on the identification of stem/progenitor cells in the SMG and how they are directed along a series of cell fate decisions to form a functional gland. The mechanisms that drive SMG organogenesis provide a template to regenerate functional salivary glands in patients who suffer from salivary hypofunction due to irreversible glandular damage after irradiation or removal of tumors. Additionally, these mechanisms may also control growth and development of other organ systems. WIREs Dev Biol 2012, 1:69–82. doi: 10.1002/wdev.4This article is categorized under:

Vertebrate Organogenesis > From a Tubular Primordium: Branched
The microRNA regulation of stem cells
Authors: Huang Xiao Albert , Lin Haifan 
Published: November 2011

AbstractThe microRNA (miRNA) pathway, as a fundamental mechanism of gene regulation, plays a key role in controlling the establishment, self‐renewal, and differentiation of stem cells. Such regulation is manifested as fine tuning the temporal‐ and tissue‐specificity of gene expression. This fine‐tuning function is achieved by (1) miRNAs form positive and negative feedback loops with transcription factors and epigenetic factors to exert concerted control of given biological processes and/or (2) different miRNAs converge to control one or more mRNA targets in a signaling pathway. These regulatory mechanisms are found in embryonic stem cells, iPS cells, and adult tissue stem cells. The distinct expression profiles of miRNAs and their regulatory roles in various types of stem cells render these RNAs potentially effective tools for clinical diagnosis and therapy. WIREs Dev Biol 2012, 1:83–95. doi: 10.1002/wdev.5This article is categorized under:

Gene Expression and Transcriptional Hierarchies > Regulatory RNA
Adult Stem Cells, Tissue Renewal, and Regeneration > Tissue Stem Cells and Niches
Adult Stem Cells, Tissue Renewal, and Regeneration > Stem Cell Differentiation and Reversion
Adult Stem Cells, Tissue Renewal, and Regeneration > Stem Cells and Disease
The role of RNA in mammalian prion protein conversion
Authors: Gomes Mariana P. B. , Vieira Tuane C. R. G. , Cordeiro Yraima , Silva Jerson L. 
Published: November 2011

AbstractPrion diseases remain a challenge to modern science in the 21st century because of their capacity for transmission without an encoding nucleic acid. PrPSc, the infectious and alternatively folded form of the PrP prion protein, is capable of self‐replication, using PrPC, the properly folded form of PrP, as a template. This process is associated with neuronal death and the clinical manifestation of prion‐based diseases. Unfortunately, little is known about the mechanisms that drive this process. Over the last decade, the theory that a nucleic acid, such as an RNA molecule, might be involved in the process of prion structural conversion has become more widely accepted; such a nucleic acid would act as a catalyst rather than encoding genetic information. Significant amounts of data regarding the interactions of PrP with nucleic acids have created a new foundation for understanding prion conversion and the transmission of prion diseases. Our knowledge has been enhanced by the characterization of a large group of RNA molecules known as non‐coding RNAs, which execute a series of important cellular functions, from transcriptional regulation to the modulation of neuroplasticity. The RNA‐binding properties of PrP along with the competition with other polyanions, such as glycosaminoglycans and nucleic acid aptamers, open new avenues for therapy. WIREs RNA 2012, 3:415–428. doi: 10.1002/wrna.118This article is categorized under:

RNA Structure and Dynamics > Influence of RNA Structure in Biological Systems
RNA Interactions with Proteins and Other Molecules > Protein–RNA Interactions: Functional Implications
RNA in Disease and Development > RNA in Disease
Preoperative Brain Natriuretic Peptide (BNP) Is a Better Predictor of Adverse Cardiac Events Compared to Preoperative Scoring System in Patients Who Underwent Abdominal Surgery
Authors: Mercantini Paolo , Di Somma Salvatore , Magrini Laura , Kazemi Nava Andrea , Scarinci Andrea , La Torre Marco , Ferri Mario , Ferri Enrico , Petrucciani Niccolò , Ziparo Vincenzo 
Published: November 2011

AbstractBackgroundCardiovascular disease is the leading cause of perioperative death in surgical patients. A variety of clinical scoring systems have been developed to predict adverse cardiovascular events. B‐type natriuretic peptide (BNP) is a sensitive and specific predictor of left ventricular systolic dysfunction and predicts first cardiovascular event and death in the general population. We present a prospective, single‐center, observational cohort study of patients undergoing major abdominal surgery and evaluate the role of BNP in predicting adverse cardiac events.MethodA total of 205 patients were included in the study. All patients were assessed by a cardiological clinical evaluation, a 12‐lead ECG report, and a preoperative and postoperative blood sample for plasmatic BNP assessment. The primary end point was the predictive power of preoperative BNP levels for adverse cardiac events until 30 days after discharge.ResultsThirty‐one of 205 (15%) patients had adverse cardiac events in the postoperative period up to 30 days after discharge. Five patients (2.4%) of these died of cardiac events. Preoperative BNP values were significantly increased in the 31 patients compared to the other patients in the postoperative period [mean = 112.93 pg/ml (range = 5–2,080) vs. 178.99 pg/ml (range = 5–3,980); median = 117 vs. 23 pg/ml; 95% CI = 49–181; p < 0.0001]. At logistic regression, a preoperative BNP value of >36 pg/ml was the only effective predictor of adverse cardiac events.ConclusionWe have demonstrated that elevated preoperative BNP levels are independent predictors of adverse cardiac events in a cohort of patients undergoing major abdominal surgery in a general surgery department, and this is the first study about this specific cohort of patients.
Thermal, food and vegetation effects on winter bird species richness of Mediterranean oakwoods
Authors: Carrascal L. M. , Villén‐Pérez S. , Seoane J. 
Published: November 2011

AbstractA better understanding of species–energy relationships needs to be developed using fine‐grained approaches that involve the use of small geographical scales of known characteristics, such as habitat heterogeneity, food availability, direct measures of temperature, and functional groups of species. We carried out a 2‐year study to analyze the effects of the thermal environment and food availability, while controlling for the influence of habitat structure, on winter species richness of birds living in oakwoods of a mountanious region of Central Spain of Mediterranean continental climate. The guild of ground‐foraging birds was selected as model organisms considering its susceptibility to winter conditions associated with unpredictable snowfalls. The spatial variation in species richness of this guild was determined by food availability, but only for those stable and predictable resources not affected by frequent snowfall (shrubs producing fruits; a complete lack of association was found with arthropod abundance on the ground). Thermal effects associated directly with air temperature, and mediated indirectly by vegetation structure providing a mosaic of sun‐shade patches, were also very influential. These patterns were highly repeatable across years. Daytime temperature had no influence on determining spatial variation in species richness, but night (minimum) temperature was a very important predictor (explained considering the lower temperatures at night, the longer duration of night, and the inability of diurnal birds to develop active behavioral thermoregulation during nighttime). This result highlights the need to consider physiological processes mediating species–environment relationships when analyzing the relationship between climatic variables and biodiversity phenomena.
Low Levels of Lipogenic Enzymes in Peritumoral Adipose Tissue of Colorectal Cancer Patients
Authors: Notarnicola Maria , Miccolis Angelica , Tutino Valeria , Lorusso Dionigi , Caruso Maria Gabriella 
Published: November 2011

AbstractLipoprotein lipase (LPL) is the crucial enzyme for intravascular catabolism of triglyceride‐rich lipoproteins. Fatty acid synthase (FAS) is a key anabolic enzyme that catalyzes the terminal steps in the novo biosynthesis of 18:2n‐6. The involvement of both LPL and FAS in tumor biology has been widely demonstrated in different studies and to verify whether there are regional differences in the expression of these enzymes in visceral adipose tissue from patients with colorectal cancer might be representative of events which sustain tumor growth. The objective of this study was to evaluate LPL and FAS activity and expression of their genes in adipose tissue adjacent to neoplasia and distant from it from patients operated for colorectal cancer. LPL enzymatic activity was evaluated by a fluorescent method and FAS activity by a radiometer assay. Reverse‐transcription and real‐time PCR were used to detect mRNA levels of two enzymes. Our findings show a significant reduction in both LPL and FAS gene expression and activity levels in adipose tissue adjacent to tumor lesion compared to those detected in paired tissue distant from neoplasia. These results underline the influence of tumor microenvironment on lipid metabolism in adipose tissue, demonstrating a tumor‐induced impairment in the formation and lipid storing capacity of adipose tissue in patients with colorectal cancer.