bluuebunny/crossref_metadata_2025_split huggingface dataset:
Diffusion and Phase Transformation at the Interface between an Austenitic Substrate and a Thermally Sprayed Coating of Ledeburitic Cold‐Work Tool Steel
Authors: Röttger Arne , Weber Sebastian , Theisen Werner , Rajasekeran Balasundaram , Vaßen Robert 
Published: February 2011

AbstractAn overlay coating against wear or corrosion on components is required for various technical applications. Thermal spraying is a well‐established and near‐net‐shape deposition method. In this work, high‐velocity oxy‐fuel spraying of two different ledeburitic cold‐work tool steels was employed to produce wear‐resistant Fe‐base coatings on a stainless steel substrate. This work focuses on the investigation of diffusion processes across the coating/substrate interface. Specimens were heat‐treated for different dwell times and then analyzed by means of EBSD, XRD, OM, as well as SEM. Results of phase formation and diffusion profiles were compared with equilibrium and diffusion calculations obtained with ThermoCALC® and DICTRA®. The influence of diffusion processes across the coating/substrate interface on the mechanical properties, such as adhesive bond strength and hardness, was investigated by shear tests and microhardness profiles.
The Pathology of Bleomycin-Induced Fibrosis Is Associated with Loss of Resident Lung Mesenchymal Stem Cells That Regulate Effector T-cell Proliferation
Authors: Jun Du , Garat Chrystelle , West James , Thorn Nathalie , Chow Kelsey , Cleaver Timothy , Sullivan Timothy , Torchia Enrique C. , Childs Christine , Shade Theodore , Tadjali Mehrdad , Lara Abigail , Nozik-Grayck Eva , Malkoski Stephen , Sorrentino Brian , Meyrick Barbara , Klemm Dwight , Rojas Mauricio , Wagner David H. , Majka Susan M. 
Published: February 2011

Abstract
Tissue-resident mesenchymal stem cells (MSCs) are important regulators of tissue repair or regeneration, fibrosis, inflammation, angiogenesis, and tumor formation. Here, we define a population of resident lung MSCs (luMSCs) that function to regulate the severity of bleomycin injury via modulation of the T-cell response. Bleomycin-induced loss of these endogenous luMSCs and elicited fibrosis (pulmonary fibrosis), inflammation, and pulmonary arterial hypertension (PAH). Replacement of resident stem cells by administration of isolated luMSCs attenuated the bleomycin-associated pathology and mitigated the development of PAH. In addition, luMSC modulated a decrease in numbers of lymphocytes and granulocytes in bronchoalveolar fluid and demonstrated an inhibition of effector T-cell proliferation in vitro. Global gene expression analysis indicated that the luMSCs are a unique stromal population differing from lung fibroblasts in terms of proinflammatory mediators and profibrotic pathways. Our results demonstrate that luMSCs function to protect lung integrity after injury; however, when endogenous MSCs are lost, this function is compromised illustrating the importance of this novel population during lung injury. The definition of this population in vivo in both murine and human pulmonary tissue facilitates the development of a therapeutic strategy directed at the rescue of endogenous cells to facilitate lung repair during injury.
Self-Renewal Versus Lineage Commitment of Embryonic Stem Cells: Protein Kinase C Signaling Shifts the Balance
Authors: Dutta Debasree , Ray Soma , Home Pratik , Larson Melissa , Wolfe Michael W. , Paul Soumen 
Published: February 2011

Abstract
The intricate molecular mechanisms that regulate ESC pluripotency are incompletely understood. Prior research indicated that activation of the Janus kinase–signal transducer and activator of transcription (STAT3) pathway or inhibition of extracellular signal-regulated kinase/glycogen synthase kinase 3 (ERK/GSK3) signaling maintains mouse ESC (mESC) pluripotency. Here, we demonstrate that inhibition of protein kinase C (PKC) isoforms maintains mESC pluripotency without the activation of STAT3 or inhibition of ERK/GSK3 signaling pathways. Our analyses revealed that the atypical PKC isoform, PKCζ plays an important role in inducing lineage commitment in mESCs through a PKCζ–nuclear factor kappa-light-chain-enhancer of activated B cells signaling axis. Furthermore, inhibition of PKC isoforms permits derivation of germline-competent ESCs from mouse blastocysts and also facilitates reprogramming of mouse embryonic fibroblasts toward induced pluripotent stem cells. Our results indicate that PKC signaling is critical to balancing ESC self-renewal and lineage commitment.
CD24: A Novel Surface Marker for PDX1-Positive Pancreatic Progenitors Derived from Human Embryonic Stem Cells
Authors: Jiang Wei , Sui Xin , Zhang Donghui , Liu Meng , Ding Mingxiao , Shi Yan , Deng Hongkui 
Published: February 2011

Abstract
Human ESCs provide a promising cell resource for the treatment of type I diabetes mellitus. Although PDX1-positive pancreatic progenitors can be efficiently generated from human ESCs by stepwise induction, further in vitro differentiation into functional, mature beta cells is not efficient or reproducible. Purification of pancreatic progenitor cells could facilitate the identification of signals that regulate beta cell differentiation and maturation. Here, we report the identification of a novel surface marker for PDX1-positive pancreatic progenitors based on an in vitro human ESC differentiation system. By costaining PDX1 and a panel of cell surface antigens at the pancreatic progenitor stage of human ESC differentiation, we discovered a positive marker, CD24. CD24-positive cells coexpressed most of the key transcription factors of pancreatic progenitors, and the expression of important pancreatic genes was greatly enriched in CD24-positive cells compared with the CD24-negative cells. In addition, CD24-positive cells could differentiate into insulin-producing cells but CD24-negative cells could not. These results indicate that CD24 could be a surface marker for PDX1-positive pancreatic progenitors derived from human ESCs. Enrichment of pancreatic progenitors with this marker will facilitate the investigation of beta cell maturation during the human ESC differentiation.
Authoring identity amidst the treacherous terrain of science: A multiracial feminist examination of the journeys of three women of color in science
Authors: Johnson Angela , Brown Jaweer , Carlone Heidi , Cuevas Azita K. 
Published: February 2011

AbstractThe study of the identity processes of women of color in science‐based fields helps us (a) find ways to support similar women, and (b) study the dynamics of inequity, within and beyond science. Participants in this study (a Black woman, a Latina, and an American Indian woman) survived inadequate high schools and discouraging college science departments to win formal recognition (fellowships, publications). Using multiracial feminist theory, including intersectionality, and practice theory, we conceptualize authoring of identity as an ongoing process. Qualitative methods were designed around Black feminist precepts of caring and personal accountability, the use of concrete experience and of dialogue (Collins, 2000a). Participants' opportunities to author legitimate science identities were constrained by their location in the matrix of oppression. They reported conflicts between their identities as women of color and as credible science students, and having racist, sexist identities ascribed to them. All became more adept at fending off negative ascription and all found settings with less identity conflict; their ability to read a situation and quickly adjust, la facultad (Anzaldúa, 1999) helped them survive. But the fact that they have needed to do this is unjust. © 2011 Wiley Periodicals, Inc., Inc. J Res Sci Teach 48: 339–366, 2011
Concept mapping and the cartography of cognition
Authors: Wandersee James H. 
Published: February 2011

AbstractSince concept maps are designed to find out what the learner knows about a subject and are, in effect, maps of cognition, this article synthesizes relevant facts, concepts, and principles from cartography and applies them to concept mapping. The metaphor of the map and its applicability for representing scientific knowledge are discussed. The context of concept mapping is presented and suggestions for successful application of the technique in the science classroom are offered. Finally, researchers are invited to conduct studies that investigate the graphic representation of scientific knowledge in order to create, evaluate, and improve the graphics and graphic metacognitive tools (such as concept mapping) which are used in science teaching.
The elaboration of concepts in three biology textbooks: Facilitating student learning
Authors: Lloyd Carol V. 
Published: February 2011

AbstractAs the levels of scientific literacy and science achievement have become issues of concern, the necessity of investigating possible causes becomes more urgent. Since textbooks have been shown to have a tremendous impact on curriculum, this is one variable of science instruction that needs further investigation. The purpose of this article is to describe how three biology books present the content related to photosynthesis through the construct of elaboration. The textbooks were selected for their differences in target audiences, as defined by student abilities. Results are discussed in terms of quantity of elaboration, relevance of ideas used to elaborate major concepts, relationship of the nature of elaboration to intended readers, and the general relationship between how texts present information and student learning.
Molecular genetics and molecular biology of dyslexia
Authors: Kere Juha 
Published: February 2011

AbstractDevelopmental dyslexia has been recognized as a distinct entity among learning disabilities as early as the late 1800s and its partially genetic nature has been firmly established by family and twin studies. The application of genetic mapping and molecular cloning methods has revealed specific genes that contribute to the genetic risk, but those known now do not yet suffice for explaining all of it. More importantly, the first genes, some of them found by the study of rare families, have indicated specific neurodevelopmental processes important for the development of dyslexia, including control of neuronal migration for the DYX1C1, DCDC2, and KIAA0319 genes, and a role of axonal and dendritic guidance suggested by the ROBO1 gene. I anticipate that forthcoming research within only a few years will yield molecular networks with fundamental roles in the molecular biology of dyslexia, and may aid in resolving relationships between comorbid disorders. WIREs Cogni Sci 2011 2 441–448 DOI: 10.1002/wcs.138This article is categorized under:

Neuroscience > Development
Assembly of a New Cadmium(II)‐bis(Triazole) Coordination Polymer Templated by Keggin Polyoxometalate
Authors: Ying Jun , Liu Xiao‐Jing , Tian Ai‐Xiang , Wang Xiu‐Li 
Published: February 2011

AbstractThrough utilizing the flexible bis(triazole) ligand 1,3‐bis(1,2,4‐triazol‐1‐y1)propane (btp), the new Keggin POM‐templated compound, [Cd2(H2O)2(btp)4(SiMo12O40)]·2H2O (1), was synthesized under hydrothermal conditions. It was characterized by single‐crystal X‐ray diffraction, elemental analysis, IR spectroscopy, thermogravimetric analysis, photoluminescence spectroscopy, and cyclic voltammetry. In compound 1, the [SiMo12O40]4– polyanions serving as template induce the Cd–bis(triazole) coordination polymer to construct a ladder‐like chain. In the 1D chain, two btp ligands act as “middle rails”. The template polyanions insert into the grids of the 1D chain. Furthermore, these chains can construct a 3D supramolecular structure through hydrogen bondings.
Expanding Laparoscopic Cholecystectomy to Rural Mongolia
Authors: Straub Catherine M. , Price Raymond R. , Matthews Douglas , Handrahan Diana L. , Sergelen Davaatseren 
Published: February 2011

AbstractBackgroundAlthough laparoscopic cholecystectomy was first introduced in Mongolia in 1994, the benefits of the laparoscopic approach have been largely unavailable to the majority of the population. The burden of gallbladder disease in Mongolia is significant. Despite the barriers to expanding laparoscopic surgery in Mongolia (lack of physical resources and adequate training opportunities, a difficult political situation, and an austere environment), the Health Sciences University of Mongolia (HSUM) began looking for ways to further the development of laparoscopy for the entire country, including the rural areas where half the population resides.MethodsCombined didactic and practical training courses lasting 2 weeks were developed collaboratively by a private nongovernmental organization and HSUM. The courses were taught at tertiary care centers in the capital city (Ulaanbaatar) and in a smaller, rural city (Erdenet), the regional northern referral center. Demographic data, preoperative diagnosis, ultrasound and operative findings, operative times, length of hospital stay, and intraoperative and postoperative complication rates were compared from 2007–2008 from hospitals in Ulaanbaatar and Erdenet.ResultsA total of 36 surgeons participated in the training classes, and a total of 410 laparoscopic cholecystectomies were performed. Ultrasound was used as a diagnostic tool in all cases. There was no significant difference in intraoperative or postoperative complications between hospitals in the capital, where the procedures were performed by skilled laparoscopic surgeons, and in Erdenet, where the training courses first introduced laparoscopic cholecystectomy. Neither were there differences in complication rates between cases during the teaching and nonteaching periods.ConclusionsLaparoscopic cholecystectomy can be expanded safely to the regional diagnostic referral centers in rural Mongolia through short‐term training courses as a method to markedly improve access and outcomes for the 50% of the country previously denied the benefits of minimally invasive surgery.
Setting the Bar for Laparoscopic Resection of Sporadic Insulinoma
Authors: Richards Melanie L. , Thompson Geoffrey B. , Farley David R. , Kendrick Michael L. , Service John F. , Vella Adrian , Grant Clive S. 
Published: February 2011

AbstractBackgroundLaparoscopic insulinoma resection (LIR) for sporadic disease is increasingly supported as a feasible and safe operation in small series of patients. To determine whether LIR is an acceptable alternative to the open operation, it is necessary to compare LIR to historical controls. The purpose of this study was to identify the skills and technology needed for LIR and establish outcome standards.MethodsA database of patients with benign sporadic insulinoma who underwent an open procedure at the Mayo Clinic was reviewed for demographics, imaging, operative/pathology reports, and outcomes. Outcomes were compared to a world‐wide meta‐analysis of patients who had undergone LIR reported in the English literature between 1996 and 2009.ResultsTwo hundred fifteen patients underwent a primary open operation for benign sporadic insulinoma. Solitary tumors were found in 97%. Meta‐analysis identified 232 patients who underwent LIR. The open and LIR groups underwent comparable operations that included enucleations (64 vs. 68%) and distal pancreatectomies (28 vs. 35%) (p = 0.06). The mean estimated blood loss, operating time, and length of stay were comparable between the open and LIR groups (p = NS). Pancreatic fistula occurred more often in the LIR group (24 vs. 11%, p < 0.05). A curative operation was performed in 98% of control patients and in 99% of the LIR group (p = NS).ConclusionsMultiple insulinomas are rare and a focused resection guided by imaging may be performed. LIR is associated with an increased incidence of pancreatic fistula. Success of LIR will depend on accurate multimodality preoperative imaging, skilled use of lap‐US to replace palpation for localization, and safe methods to dissect the tumor adjacent to the pancreatic duct.
Impacts of changes in climate variability on regional vegetation in China: NDVI‐based analysis from 1982 to 2000
Authors: Meng Meng , Ni Jian , Zong Meijuan 
Published: February 2011

AbstractThree methods were used to distinguish the characteristics of changes in climate variability and normalized difference vegetation index (NDVI) during the period from 1982 to 2000 in China. Great changes in climate variability and an increased trend in NDVI were observed. The changes in precipitation variability were greater than the changes in temperature variability in each month, which is attributed to changes in the monsoon system in East Asia. The abrupt changes in climate and NDVI were more significant in 1983 than in the other years due to the impacts of El Niño/Southern Oscillation (ENSO). Using these results, the influences of changes in climate variability on vegetation were studied in the whole nation, and eight regions were defined according to the vegetation division map of China. The results show that abrupt climate changes at a small scale cannot cause abrupt NDVI changes directly. At a nationwide level, over a longer time scale the persistence of above/below average temperature determines the changes in NDVI; at a shorter time scale, changes in the magnitude of precipitation influence NDVI significantly. Such regional climate variability affects vegetation in different ways owing to the diversity of vegetation types, climatic conditions and topography of the land.
Percentage of protein, lipids, and carbohydrates in the diet of badger (Meles meles) populations across Europe
Authors: Remonti Luigi , Balestrieri Alessandro , Prigioni Claudio 
Published: February 2011

AbstractAlthough originally evolved as predators, several species of mammalian carnivores exhibit a great trophic diversity, ranging from hypercarnivory to a high consumption of vegetable food. Habitat characteristics influence food availability and consequently could affect the nutritional composition of the diet of generalist species. By reviewing the available literature, we tested the hypothesis that intraspecific differences in the food habits of badgers (Meles meles) living in different habitats across Europe could affect the percentage of macronutrients (i.e., protein, lipids, and carbohydrates) in their diet. Notwithstanding the different composition of the diet, the percentage of protein and lipids fed by badgers did not vary among temperate forest‐pasture mosaics, Mediterranean woodlands, or scrublands and arable lands, suggesting a certain form of regulation of the diet balance. The percentage of carbohydrates was similar in the first two habitats, while it was fivefold higher in arable lands, where cereals were the main food of badgers and were consumed throughout the year. Earthworm consumption by badgers was positively related to the latitude, while the lack of any latitudinal or altitudinal pattern in protein consumption reflected the absence of a gradient in carnivory. A slight inverse latitudinal gradient in lipids consumption probably depended on the use, in southern Europe, of vegetal foods rich in lipids. We hypothesize that in agricultural landscapes dominated by crop cultivations, the decline of animal prey (i.e., earthworms, insects, and vertebrates) due to habitat loss forced badgers to increase the percentage of protein in their diet by over‐eating cereals, with the consequence of a disproportionate increase in carbohydrate consumption.
Plant clipping may cause overestimation of soil respiration in a Tibetan alpine meadow, southwest China
Authors: Li Guoyong , Sun Shucun 
Published: February 2011

AbstractThe chamber‐based method is currently the most popular approach used for measuring soil respiration of various ecosystems. When this method is applied, aboveground plant tissues within the chamber need to be clipped some time (usually 24 h) before measuring soil respiration. However, plant clipping may change soil temperature and hence soil respiration because soil respiration is highly temperature‐dependent, particularly in cold regions. To determine to what extent soil respiration may be changed by the clipping, we measured soil temperature and respiration of an alpine meadow of southwest China using a chamber‐based method over an annual cycle. Based on the measurements, an exponential equation was built to describe the relationship between soil respiration and temperature. Concurrently we measured the soil temperature in clipped and unclipped plots on sunny days of the study months in another independent experiment; subsequently soil respiration was estimated for these plots using the exponential equation. Though daily mean soil temperature was insignificantly different between the clipped and unclipped plots, the clipping increased soil temperature at 5 cm depth by up to 4.3°C at daytime but decreased by up to 1.4°C at nighttime during the growing season. The changes were 2.2 and 1.5°C at daytime and nighttime, respectively, in the non‐growing season. It was calculated that the clipping manipulation caused an overestimation of soil respiration by 28.6 and 21.2% for the growing and non‐growing seasons, respectively; nevertheless, this calculated overestimation should differ from the actual one because the data were collected on sunny days only.
Integrated Countercurrent Two‐Stage Extraction and Cream Demulsification in Enzyme‐Assisted Aqueous Extraction of Soybeans
Authors: de Moura J. M. L. N. , Maurer D. , Jung S. , Johnson L. A. 
Published: February 2011

AbstractCountercurrent two‐stage extraction and cream demulsification were fully integrated and demonstrated on laboratory scale (2 kg soybeans) wherein the enzyme used for demulsifying the cream was used in the extraction steps of enzyme‐assisted aqueous extraction processing (EAEP). Protease enzyme (Protex 6L) entered the integrated EAEP process in the demulsification step and the skim, which contained the enzyme, resulting from breaking the cream emulsion was recycled upstream into the second extraction stage and then to the first extraction stage. Oil, protein and solids extraction yields of 96.1 ± 1.4%, 89.3 ± 1.0%, and 81.2 ± 2.0%, respectively, were achieved with steady‐state operation of integrated EAEP. Higher degrees of protein hydrolysis (DH) were obtained when using the integrated process compared with the process when not recycling the enzyme. Higher extents of hydrolysis probably increased emulsion formation thereby affecting lipid distribution among the fractions. Overall free oil recovery was reduced due to more oil shifting to the skim fraction.
Initial evidence for the role of CACNA1C on subcortical brain morphology in patients with bipolar disorder
Authors: Perrier E. , Pompei F. , Ruberto G. , Vassos E. , Collier D. , Frangou S. 
Published: February 2011

AbstractBackgroundThe polymorphism rs1006737 within the CACNA1C gene is associated with increased risk for bipolar disorder (BD) and variations in brain morphology and function of subcortical regions. Here we sought to investigate the influence of CACNA1C polymorphism on key subcortical brain structures implicated in the pathophysiology of BD.MethodsStructural magnetic resonance imaging scans were acquired from 41 euthymic patients with BD and 40 healthy controls, who were also genotyped for the CACNA1C rs1006737 polymorphism. The effect of diagnosis, genotype and their interaction was examined in predefined volumes of interest in the basal ganglia, hypothalamus and amygdala extracted using SPM5.ResultsCarriers of the CACNA1C rs1006737 risk allele showed increased grey matter density in the right amygdala and right hypothalamus irrespective of diagnosis. An interaction between genotype and diagnosis was observed in the left putamen which was smaller in BD patients carrying the risk allele than in healthy controls.Conclusions:The CACNA1C rs1006737 polymorphism influences anatomical variation within subcortical regions involved in emotional processing.