bluuebunny/crossref_metadata_2025_split huggingface dataset:
Model‐based rational strategy for chromatographic resin selection
Authors: Nfor Beckley K. , Zuluaga Diego S. , Verheijen Peter J. T. , Verhaert Peter D. E. M. , van der Wielen Luuk A. M. , Ottens and Marcel 
Published: August 2011

AbstractA model‐based rational strategy for the selection of chromatographic resins is presented. The main question being addressed is that of selecting the most optimal chromatographic resin from a few promising alternatives. The methodology starts with chromatographic modeling, parameters acquisition, and model validation, followed by model‐based optimization of the chromatographic separation for the resins of interest. Finally, the resins are rationally evaluated based on their optimized operating conditions and performance metrics such as product purity, yield, concentration, throughput, productivity, and cost. Resin evaluation proceeds by two main approaches. In the first approach, Pareto frontiers from multiobjective optimization of conflicting objectives are overlaid for different resins, enabling direct visualization and comparison of resin performances based on the feasible solution space. The second approach involves the transformation of the resin performances into weighted resin scores, enabling the simultaneous consideration of multiple performance metrics and the setting of priorities. The proposed model‐based resin selection strategy was illustrated by evaluating three mixed mode adsorbents (ADH, PPA, and HEA) for the separation of a ternary mixture of bovine serum albumin, ovalbumin, and amyloglucosidase. In order of decreasing weighted resin score or performance, the top three resins for this separation were ADH > PPA > HEA. The proposed model‐based approach could be a suitable alternative to column scouting during process development, the main strengths being that minimal experimentation is required and resins are evaluated under their ideal working conditions, enabling a fair comparison. This work also demonstrates the application of column modeling and optimization to mixed mode chromatography. © 2011 American Institute of Chemical Engineers Biotechnol. Prog., 2011
CO2 Subsequent Chemistry: Direct Synthesis of Dimethyl Carbonate by Carboxylation of Methanol with Cerium‐based Mixed Oxides
Authors: Hofmann Heiko Jürgen , Brandner Armin , Claus Peter 
Published: August 2011

AbstractIn der vorliegenden Arbeit wird die Synthese von Cer‐basierten Mischoxiden über eine Oxalat‐Gel‐Methode und deren Eignung in der Katalyse der Carboxylierung von Methanol mit CO2 beschrieben. Die Beurteilung der Aktivität erfolgt in flüssiger Phase. Am Beispiel von Ceroxid wird der Einfluss des Drucks, der Temperatur und der Zusammensetzung des Eduktgemisches in der Gas‐ und Flüssigphase untersucht. Die Lage des Gleichgewichtes sowie die strukturellen Eigenschaften der Katalysatoren, charakterisiert durch Röntgenbeugung, FTIR‐ und UV/VIS‐Spektroskopie sowie Physisorption, werden diskutiert.
NK cells can generate from precursors in the adult human liver
Authors: Moroso Viviana , Famili Farbod , Papazian Natalie , Cupedo Tom , van der Laan Luc J. W. , Kazemier Geert , Metselaar Herold J. , Kwekkeboom Jaap 
Published: August 2011

AbstractHepatic NK cells constitute ∼40% of hepatic lymphocytes and are phenotypically and functionally distinct from blood NK cells. Whether hepatic NK cells derive from precursors in the BM or develop locally from hepatic progenitors is still unknown. Here, we identify all five known sequential stages of NK‐cell development in the adult human liver and demonstrate that CD34+ hepatic progenitors can generate functional NK cells. While early NK‐cell precursors (NKPs) were similar in liver and blood, hepatic stage 3 NKPs displayed immunophenotypical differences, suggesting the onset of a liver‐specific NK‐cell development. Hepatic stage 3 NKPs were RORCneg and did not produce IL‐17 or IL‐22, excluding them from the lymphoid tissue‐inducer (LTi) subset. In vitro culture of hepatic NKPs gave rise to functional NK cells exhibiting strong cytotoxicity against K562 targets. To determine whether hepatic NKPs are stably residing in the liver, we analyzed donor and recipient‐derived cells in transplanted livers. Shortly after liver transplantation all donor NKPs in liver grafts were replaced by recipient‐derived ones, indicating that hepatic NKPs are recruited from the bloodstream. Together, our results show that NKPs are continuously recruited from peripheral blood into the liver and can potentially differentiate into liver‐specific NK cells.
Syntheses, Structure, Physical Properties, and Electronic Structures of DyCuxAl12–x (4.0 ≤ x ≤ 6.0)
Authors: Lin Hua , Cai Wei‐Zhao , Shi Yong‐Fang , Chen Ling 
Published: August 2011

AbstractThe title phases are synthesized from an elemental mixture by high temperature solid‐state reactions and the single‐crystal structure refinement of DyCu5.51(4)Al6.49(4) reveals its ThMn12‐type structure. The structure can be viewed as a 3D condensed network of Dy‐centered, 20 vertex [Al4Cu8M8] polyhedra, in which Cu/Al disorder has been observed on the M site (8j). A homogeneous range of DyCuxAl12–x (4.0 ≤ x ≤ 6.0) has been observed. The metallic electrical conductivities of DyCuxAl12–x decrease as x increases following the decreasing trend of the densities of states at the Fermi level based on tight‐bonding linear muffin‐tin orbital (TB‐LMTO) calculations.
Positive fantasies predict low academic achievement in disadvantaged students
Authors: Kappes Heather Barry , Oettingen Gabriele , Mayer Doris 
Published: August 2011

AbstractUnlike other forms of positive thinking (e.g., expectations), research finds that positive fantasies (experiencing one's thoughts and mental images about the future positively) predict low effort and little success in several domains. However, for vocational education students of low socioeconomic status and minority ethnicity, for whom the present environment is especially difficult, perhaps it would be appropriate to indulge in positive fantasies that depict the future as bright and easily attained. Three studies show that this is not the case. Positive future fantasies measured early in the program predicted more days absent (Studies 2–3) and lower grades at the end of the program (Studies 1–3), even when adjusting for initial academic competence, expectations of successful achievement, and self‐discipline. Expectations of successful achievement predicted fewer days absent and higher grades only when measured midway through the school year, once participants had experience with their own academic standing (Study 3). Results indicate that positive fantasies, which allow people to indulge in images of a bright future, predict poor achievement even in vocational students immersed in a particularly difficult environment. Copyright © 2011 John Wiley & Sons, Ltd.
Tumor suppressor protein kinase Chk2 is a mediator of anoikis of intestinal epithelial cells
Authors: Yoo Byong Hoon , Berezkin Alexander , Wang Yanfei , Zagryazhskaya Anna , Rosen Kirill V. 
Published: August 2011

AbstractResistance of carcinoma cells to anoikis, apoptosis that is normally induced by detachment of nonmalignant epithelial cells from the extracellular matrix, is thought to be critical for carcinoma progression. Molecular mechanisms that control anoikis of nonmalignant and cancer cells are understood poorly. In an effort to understand them we found that detachment of nonmalignant intestinal epithelial cells triggers upregulation of Chk2, a pro‐apoptotic protein kinase that has never been implicated in anoikis and has been thought to kill cells mainly under the conditions compromising genome integrity. We found that enforced downregulation of Chk2 protects intestinal epithelial cells from anoikis. Chk2 can kill cells by stabilizing p53 tumor suppressor protein or via p53‐independent mechanisms, and we established that Chk2‐mediated anoikis of intestinal epithelial cells is p53‐independent. We further found that, unlike nonmalignant intestinal epithelial cells whose anoikis is triggered by detachment‐induced Chk2 upregulation, intestinal epithelial cells carrying oncogenic ras, a known inhibitor of anoikis, remain anoikis‐resistant in response to enforced Chk2 upregulation. By contrast, drugs, such as topoisomerase I inhibitors, that can kill cells via Chk2‐indpendent mechanisms, efficiently triggered anoikis of ras‐transformed cells. Thus, oncogenic ras can prevent Chk2 from triggering anoikis even when levels of this protein kinase are elevated in cancer cells, and the use of therapeutic agents that kill cells in a Chk‐2‐independent, rather than Chk‐2‐dependent, manner could represent an efficient strategy for overcoming ras‐induced anoikis resistance of these cells. We conclude that Chk‐2 is an important novel component of anoikis‐promoting machinery of intestinal epithelial cells.
Therapeutic apheresis in critically ill patients
Authors: Sanford Kimberly W. , Balogun Rasheed A. 
Published: August 2011

AbstractTherapeutic apheresis procedures in critically ill patients comprises of therapeutic plasma exchange in most cases but also less commonly, erythrocytapheresis (red cell exchange), thrombocytapheresis, or leukocytapheresis. These procedures present a number of challenges to the apheresis healthcare team, and there are myriad beneficial and adverse effects for patients. In this patient population, one has to weigh the risks against the benefits and especially in those situations where apheresis is requested as a treatment when other alternative therapies have failed. Therapeutic plasma exchange is capable of removing toxins, pathologic auto‐ and allo‐antibodies but will also remove beneficial medications, clotting factors and cations which are chelated by citrate anticoagulant. Herein, we review clinically significant issues that are commonly encountered in patients that are in the intensive care unit and have conditions that require therapeutic apheresis. J. Clin. Apheresis 2011. © 2011 Wiley‐Liss, Inc.
Digestive flexibility during fasting in the characid fishHyphessobrycon luetkenii
Authors: Gaucher Lucia , Vidal Nicolás , D'Anatro, Alejandro , Naya Daniel E. 
Published: August 2011

AbstractDigestive flexibility is a widespread phenomenon among animals, and the congruence between empirical data and optimal digestion models strongly supports the idea that it has evolved by natural selection. However, current understanding of the evolution of this amazing flexibility is far from being comprehensive. Evidence from vertebrate tetrapods suggests that there are two major mechanisms for intestinal down‐regulation during fasting periods: a decrease in the number of enterocytes in the mucosal epithelium in endothermic species, and a transitional epithelium in concert with a marked hypotrophy of enterocytes in ectothermic species. Here, we analyze the intestinal changes, at the morphological and histological levels, occurring after 9 and 16 days of fasting in a small characid fish species (Hyphessobrycon luetkenii). We found that short‐term fasting was correlated with a marked down‐regulation of gut size (i.e., caeca and intestine dry mass fall to a 42.3%, while intestinal length was reduced to a 73.9% of the feeding values) and that these changes were accompanied by a shift in intestinal epithelial organization from a simple columnar to pseudostratified one. This result, in conjunction with data on changes in enterocyte turnover rates during fasting in other fish species, suggests that gut regulation at both levels, cell renewal rate and epithelia configuration, is the basal condition to all tetrapods. More data, especially in some key taxonomic groups (e.g., fish that follow an endothermic strategy), will be needed in order to reach a clear understanding of digestive flexibility evolution. J. Morphol., 2011. © 2011 Wiley Periodicals, Inc.
Spectral characterization of squeaking in ceramic‐on‐ceramic total hip arthroplasty: Comparison of in vitro and in vivo values
Authors: Sariali Elhadi , Jin Zhongmin , Stewart Todd , Fisher John 
Published: August 2011

AbstractSqueaking is a cause for concern in total hip arthroplasty (THA). However, the definition of this sound remains vague. Our goals were to characterize spectrally the squeaking in vitro under lubricated conditions and to compare the in vitro frequencies to in vivo frequencies. Four patients, who presented with a squeaking after ceramic‐on‐ceramic THA were investigated. In addition, 3 alumina ceramic 32 mm diameter components were tested in vitro under edge loading conditions using a friction simulator. Tests were conducted under lubricated conditions without and with the addition of a third body alumina particle. In vitro, no squeaking occurred under edge loading conditions. However, with the addition of a third body particle in the contact region, squeaking was obtained; the dominant frequency was 2.6 kHz. In vivo, the main recorded sound frequencies were: 2.3, 2.24, and 2.46 kHz for squeakers during walking and 1.45 kHz for a squeaker rising from a bent position. The in vivo recordings had a dominant frequency similar to, but slightly lower than, the in vitro values. Two types of squeaking were found in vivo and characterized spectrally. The rising squeaker had intermittent squeaking corresponding to a lower fundamental frequency compared to the walking squeakers. This finding suggests two different mechanism of squeaking. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 30:185–189, 2012
The interrelation of trabecular microstructural parameters of the greater tubercle measured for different species
Authors: Hölzer Andreas , Pietschmann Matthias F. , Rösl Christine , Hentschel Markus , Betz Oliver , Matsuura Maiko , Jansson Volkmar , Müller Peter E. 
Published: August 2011

AbstractIn the present study the trabecular microstructural parameters (bone volume fraction, trabecular thickness, trabecular separation, trabecular number, connectivity density, degree of anisotropy, and structure model index) of the greater tubercle of the humeral head were measured for human healthy, human osteopenic, ovine, bovine, and porcine bones using micro‐computed tomography. Except for trabecular thickness and degree of anisotropy the values of the trabecular microstructural parameters generally differed significantly between species. Thus, only the species for which the implant is designed should be used for in vitro mechanical tests on the stability of implants in trabecular bone. Multivariate regression analysis showed that the microstructural parameters have similar principal interrelations in all species. The most significant relations were found between trabecular thickness and bone volume fraction (median (over all species) p < 0.001), trabecular number and bone volume fraction (p = 0.001), the structural change from plates to rods and bone volume fraction (p < 0.001) as well as between connectivity density and trabecular number (p < 0.001). Trabecular thickness, trabecular number, and the structural change from plates to rods each contributed to the bone volume fraction approximately to the same extent. Based on the similar principal interrelations of the trabecular microstructural parameters found in all investigated species the design of trabecular microstructure in the greater tubercle follows similar phenomenological mechanisms in all species. Thus, in vivo experiments on trabecular bone healing and osteoporosis research for application in humans can be conducted in ovine, bovine, or porcine species. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 30:429–434, 2012
Proteome profile of the pipping muscle in broiler embryos
Authors: Sokale Adebayo , Peebles Edgar D. , Zhai Wei , Pendarvis Ken , Burgess Shane , Pechan Tibor 
Published: August 2011

AbstractThis study is the first proteomics analysis of the muscularis complexus (pipping muscle) in chicken (Gallus gallus) broiler embryos. We used differential detergent fractionation and nano‐HPLC‐MS/MS analysis to identify 676 proteins from all cellular components. The identified proteins were functionally classified in accordance with their involvement in various cellular activities.
Ranking support vector machine for multiple kernels output combination in protein–protein interaction extraction from biomedical literature
Authors: Yang Zhihao , Lin Yuan , Wu Jiajin , Tang Nan , Lin Hongfei , Li Yanpeng 
Published: August 2011

AbstractKnowledge about protein–protein interactions (PPIs) unveils the molecular mechanisms of biological processes. However, the volume and content of published biomedical literature on protein interactions is expanding rapidly, making it increasingly difficult for interaction database curators to detect and curate protein interaction information manually. We present a multiple kernel learning‐based approach for automatic PPI extraction from biomedical literature. The approach combines the following kernels: feature‐based, tree, and graph and combines their output with Ranking support vector machine (SVM). Experimental evaluations show that the features in individual kernels are complementary and the kernel combined with Ranking SVM achieves better performance than those of the individual kernels, equal weight combination and optimal weight combination. Our approach can achieve state‐of‐the‐art performance with respect to the comparable evaluations, with 64.88%F‐score and 88.02% AUC on the AImed corpus.
Low‐voltage and high‐stability p‐type doped blue organic light‐emitting diodes with bilayer hole‐injection layers
Authors: Lu Lin , Yu Jianning , Long Li , Yu Fangfang , Zhang Jianhua , Zhang Hao , Wei Bin 
Published: August 2011

AbstractWe report low‐voltage and high‐stability blue organic light‐emitting diodes (OLEDs) with a peak at 470 nm, which are composed of tetrafluorotetracyano‐quinodimethane (F4‐TCNQ) doped 4,4′4″‐Tris(N‐(2‐naphthyl)‐N‐phenyl‐amino)‐triphenylamine(2T‐NATA) and additional 2T‐NATA as a hole injection layer. Compared to undoped devices, the operating voltage of p‐type doped blue OLEDs can decrease by 1.5 V. Furthermore, the use of 2T‐NATA as a blocking layer to fluorine diffusion was found to improve device lifetime and chromatic stability greatly, the half‐luminance decay reached about 3800 h at the initial luminance of 3000 cd/m2. The role of the thickness of F4‐TCNQ doped 2T‐NATA has also been investigated.
NetDS: a Cytoscape plugin to analyze the robustness of dynamics and feedforward/feedback loop structures of biological networks
Authors: Le Duc-Hau , Kwon Yung-Keun 
Published: August 2011

Abstract
Summary: NetDS is a novel Cytoscape plugin that conveniently simulates dynamics related to robustness, and examines structural properties with respect to feedforward/feedback loops. It can evaluate how robustly a network sustains a stable state against mutations by employing a Boolean network model. In addition, the plugin can examine all feedforward/feedback loops appearing in a network and determine whether or not a pair of loops is coupled. Random networks can also be generated to evaluate whether or not an interesting finding in real biological networks is significantly random.
Availability: NetDS is freely available for non-commercial purposes at http://netds.sourceforge.net/.
Contact: kwonyk@ulsan.ac.kr
Supplementary information: Supplementary data are available at Bioinformatics online.
Trends in adolescent alcohol use: effects of age, sex and cohort on prevalence and heritability
Authors: Geels Lot M. , Bartels Meike , van Beijsterveldt Toos C. E. M. , Willemsen Gonneke , van der Aa Niels , Boomsma Dorret I. , Vink Jacqueline M. 
Published: August 2011

ABSTRACTAims  To determine the effect of age, sex and cohort on the prevalence and genetic architecture of adolescent alcohol use (AAU).Design  Survey study in participants registered with the Netherlands Twin Register.Setting  Twins from the general population.Participants  Two cohorts (data collected in 1993 and 2005–08) of twins aged 13–15, 16–17 and 18–21 years. In 1993 and 2005–08 a total of 3269 and 8207 twins, respectively, took part.Measurements  Survey data on initiation and frequency of alcohol use and quantity of alcohol consumed.Findings  The prevalence of alcohol initiation increased between 1993 and 2005–08 for both males and females. The largest difference was for girls observed at ages 13–15, where the prevalence increased from 59.5% to 72.4%. We also found increases in prevalence across cohorts for quantity of alcohol consumed and non‐significant increases for frequency of alcohol use. From age 16 onwards, boys drank more frequently and larger quantities than girls. Genetic model fitting revealed that the genetic architecture of AAU did not differ between birth cohorts, nor were there differences between boys and girls. Genetic factors explained between 21% and 55% of individual differences in alcohol measures throughout adolescence. Shared environment explained between 17% and 64% of variance in alcohol use, across different age groups and alcohol measures.Conclusions  In the Netherlands, the prevalence of alcohol initiation, frequency and quantity has increased in adolescents over a 15‐year period, but there are no changes in the genetic architecture of adolescent alcohol use.
Ingredients for protist coexistence: competition, endosymbiosis and a pinch of biochemical interactions
Authors: Müller Johann P. , Hauzy Céline , Hulot Florence D. 
Published: August 2011

Summary1. The interaction between mutualism, facilitation or interference and exploitation competition is of major interest as it may govern species coexistence. However, the interplay of these mechanisms has received little attention. This issue dates back to Gause, who experimentally explored competition using protists as a model [Gause, G.F. (1935) Vérifications expérimentales de la théorie mathématique de la lutte pour la vie. Actualités Scientifiques et Industrielles, 277]. He showed the coexistence of Paramecium caudatum with a potentially allelopathic species, Paramecium bursaria.2. Paramecium bursaria hosts the green algae Chlorella vulgaris. Therefore, P. bursaria may benefit from carbohydrates synthesised by the algae. Studying endosymbiosis with P. bursaria is possible as it can be freed of its endosymbiont. In addition, C. vulgaris is known to produce allelochemicals, and P. bursaria may benefit also from allelopathic compounds.3. We designed an experiment to separate the effects of resource exploitation, endosymbiosis and allelopathy and to assess their relative importance for the coexistence of P. bursaria with a competitor that exploits the same resource, bacteria. The experiment was repeated with two competitors, Colpidium striatum or Tetrahymena pyriformis.4. Results show that the presence of the endosymbiont enables the coexistence of competitors, while its loss leads to competitive exclusion. These results are in agreement with predictions based on resource equilibrium density of monocultures (R*) supporting the idea that P. bursaria’s endosymbiont is a resource provider for its host. When P. bursaria and T. pyriformis coexist, the density of the latter shows large variation that match the effects of culture medium of P. bursaria. Our experiment suggests these effects are because of biochemicals produced in P. bursaria culture.5. Our results expose the hidden diversity of mechanisms that underlie competitive interactions. They thus support Gauses’s speculation (1935) that allelopathic effects might have been involved in his competition experiments. We discuss how a species engaged both in competition for a resource and in costly interference such as allelopathy may counterbalance these costs with a resource‐provider endosymbiont.