bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Coordination Chemistry Study of Solvated Thorium(IV) Ions in Two Oxygen‐Donor Solvents
Authors: Torapava Natallia , Lundberg Daniel , Persson Ingmar 
Published: October 2011

AbstractThe structures of the dimethyl sulfoxide (dmso) and N,N′‐dimethylpropyleneurea (dmpu) solvated thorium(IV) ions have been studied in solution by extended X‐ray absorption fine structure (EXAFS), and the structure of the solid oxonium bis[nonakis(κO‐dimethyl sulfoxide)]thorium(IV) trifluoromethanesulfonate dihydrate, (H3O)[Th((CH3)2SO)9]2(CF3SO3)9·2H2O (1) has been determined by single‐crystal X‐ray diffraction and EXAFS. Compound 1 was crystallized by evaporating a saturated dmso solution. It consists of two individual nonakis(κO‐dimethyl sulfoxide)thorium(IV) units, both of which have a tricapped trigonal prismatic configuration, as also found in nonakis(dimethyl sulfoxide)thorium(IV) perchlorate previously reported. Mean Th–O bond lengths of 2.47 and 2.43 Å are found for the two structural units, respectively, for which the differences may be explained by differences in occupancy and temperature factors. The EXAFS data of 1 revealed mean Th–O and S–O bond lengths of 2.449(3) and 1.525(3) Å, respectively, and a Th–O–S bond angle of 135.2(5)° to give a Th···S distance of 3.665(7) Å. In dmso solution, the mean Th–O and S–O bond lengths are 2.447(3) and 1.534(3) Å, respectively, the Th–O–S bond angle is 133.5(5)°, and there is a Th···S distance of 3.672(7) Å. The Th–O bond‐length distribution is somewhat asymmetric in both samples with Rmax values of 2.424 and 2.422 Å for 1 and solution, respectively. In dmpu solution, the Th–O and C–O bond lengths are 2.404(5) and 1.264(2) Å, respectively, and there is a Th–O–C angle of 157.1(5)° to give a Th···C distance of 3.594(7) Å. The observed Th–O bond length indicates strongly that thorium(IV) is eight‐coordinate in dmpu.
Design, Synthesis, Molecular Docking and Crystal Structure Prediction of New Azasugar Analogues of α‐Glucosidase Inhibitors
Authors: Pistarà Venerando , Rescifina Antonio , Punzo Francesco , Greco Graziella , Barbera Vincenzina , Corsaro Antonino 
Published: October 2011

AbstractThis work deals with the design and synthesis of α‐glucosidase inhibitors. In order to perform this task, a molecular docking study was carried out with the N‐terminal catalytic subunit of human maltase glucoamylase, which evidenced a partially empty, hydrophobic part of the docking pocket. As a consequence, we decided to improve the docking abilities of the known α‐glucosidase inhibitor MDL 73495 and carried out the synthesis of new N‐glycosyl‐derived analogues. The addition of a hydrophobic methyl group at C‐5′ax, the concomitant elimination of the equatorial hydroxy group, the inversion of the configuration at C‐4 in the sugar unit and the substitution of the hydroxy group at C‐6′ with an amino group led to 6′‐deoxy‐6′‐amino‐6a. This compound showed the lowest in silico binding affinity among a set of compounds, whose experimental activity has been reported. Bearing these results in mind, we synthesized 6a and 6b. Because of the lack of large amounts of products, which are necessary to perform crystallization, the crystal structures of 6a and 6b were predicted in silico. These can be considered as models for future X‐ray powder diffraction characterization of these two compounds.
Chalcogenoacetylenes Obtained by Indium(III) Catalysis: Dual Catalytic Activation of Diorgano Dichalcogenides and Csp–H Bonds
Authors: Rampon Daniel S. , Giovenardi Rodrigo , Silva Tiago L. , Rambo Raoní S. , Merlo Aloir A. , Schneider Paulo H. 
Published: October 2011

AbstractA new approach for the one‐pot synthesis of alkynyl chalcogenides, exemplified mainly by selenides, was developed in which dual activation of diorgano dichalcogenides and terminal acetylenes is achieved by using an indium(III) catalyst. The method has advantages of broad substrate scope, simple operation, mild reaction conditions, and good yields. A plausible reaction mechanism is proposed.
A meta‐analysis of the effects of speakers' accents on interpersonal evaluations
Authors: Fuertes Jairo N. , Gottdiener William H. , Martin Helena , Gilbert Tracey C. , Giles Howard 
Published: October 2011

AbstractThis paper reports a meta‐analysis of the empirical literature on the effects of speakers' accents on interpersonal evaluations. Our review of the published literature uncovered 20 studies that have compared the effects of standard accents (i.e., the accepted accent of the majority population) versus non‐standard accents (i.e., accents that are considered foreign or spoken by minorities) on evaluations about the speakers. These 20 studies yielded 116 independent effect sizes on an array of characteristics that were selected by the original researchers. We classified each of the characteristics as belonging to one of three domains that have been traditionally discussed in this area, namely status (e.g., intelligence, social class), solidarity (trustworthiness, in‐group–out‐group member), and dynamism (level of activity and liveliness). The effect was particularly strong when American Network accented speakers were compared with non–standard‐accented speakers. These results underscore prior research showing that speakers' accents have powerful effects on how others perceive them. These and other results are discussed in the context of the literature along with implications for future research in this area. Copyright © 2011 John Wiley & Sons, Ltd.
The role of rock surface hardness and internal moisture in tafoni development in sandstone
Authors: Mol Lisa , Viles Heather A. 
Published: October 2011

ABSTRACTThe development of cavernous weathering features such as tafoni remains poorly understood. In particular, the roles played by internal moisture and case hardening remain unclear. In this study, Electric Resistivity Tomography (ERT) has been used to map moisture distribution within inner walls of tafoni developed in sandstone, and an Equotip device used to measure rock surface hardness as a proxy measure of the degree of weathering and case hardening. Seven large tafoni in the Golden Gate Highlands National Park (South Africa), varying in size and degree of development have been monitored. A dynamic relationship between surface hardness, degree of weathering and internal moisture regimes has been found. We propose a new conceptual model which illustrates the complex interaction between case hardening and internal moisture and suggests a new direction for cavernous weathering research. Copyright © 2011 John Wiley & Sons, Ltd.
Transient CO2 leakage and injection in wellbore‐reservoir systems for geologic carbon sequestration
Authors: Pan Lehua , Oldenburg Curtis M. , Pruess Karsten , Wu Yu‐Shu 
Published: October 2011

AbstractAt its most basic level, the injection of CO2 into deep reservoirs for geologic carbon sequestration (GCS) involves a system comprising the wellbore and the target reservoir, the wellbore being the only conduit available to emplace the CO2. Wellbores in general have also been identified as the most likely conduit for CO2 and brine leakage from GCS sites, especially those in sedimentary basins with historical hydrocarbon production. We have developed a coupled wellbore and reservoir model for simulating the dynamics of CO2 injection and leakage through wellbores, and we have applied the model to situations relevant to geologic CO2 storage involving upward flow (e.g. leakage) and downward flow (injection). The new simulator integrates a wellbore‐reservoir system by assigning the wellbore and reservoir to two different sub‐domains in which flow is controlled by appropriate laws of physics. In the reservoir, we model flow using a standard multiphase Darcy flow approach. In the wellbores, we use the drift‐flux model and related conservation equations for describing transient two‐phase non‐isothermal wellbore flow of CO2‐water mixtures. Applications to leakage test problems reveal transient flows that develop into quasi‐steady states within a day if the reservoir can maintain constant conditions at the wellbore. Otherwise, the leakage dynamics could be much more complicated than the simple quasi‐steady‐state flow, especially when one of the phases flowing in from the reservoir is near its residual saturation. A test problem of injection into a depleted (low‐pressure) gas reservoir shows transient behavior out to several hundred days with sub‐critical conditions in the well disappearing after 240 days. © 2011 Society of Chemical Industry and John Wiley & Sons, Ltd
Synthesis of cyclic carbonates from CO2 and diols via electrogenerated cyanomethyl anion
Authors: Wang Huan , Wu La‐Xia , Zhao Jian‐Qing , Li Rui‐Na , Zhang Ai‐Jian , Kajiura Hisashi , Li Yong‐Ming , Lu Jia‐Xing 
Published: October 2011

AbstractThe electrogenerated cyanomethyl anion reacts with diols in the presence of CO2 to yield the corresponding cyclic carbonates in moderated yields. The reported methodology has been carried out under mild conditions, avoiding any addition of classical bases, catalysts. In this communication, the effects of reaction conditions – such as supporting electrolyte, cathode material, current densities, charge amount, diol concentration – have been investigated to optimize the carbonates yield. © 2011 Society of Chemical Industry and John Wiley & Sons, Ltd
Quantitative liver function tests improve the prediction of clinical outcomes in chronic hepatitis C: Results from the hepatitis C antiviral long-term treatment against cirrhosis trial
Authors: Everson Gregory T. , Shiffman Mitchell L. , Hoefs John C. , Morgan Timothy R. , Sterling Richard K. , Wagner David A. , Lauriski Shannon , Curto Teresa M. , Stoddard Anne , Wright Elizabeth C. 
Published: October 2011

Abstract

Risk for future clinical outcomes is proportional to the severity of liver disease in patients with chronic hepatitis C virus (HCV). We measured disease severity by quantitative liver function tests (QLFTs) to determine cutoffs for QLFTs that identified patients who were at low and high risk for a clinical outcome. Two hundred and twenty-seven participants in the Hepatitis C Antiviral Long-term Treatment Against Cirrhosis (HALT-C) Trial underwent baseline QLFTs and were followed for a median of 5.5 years for clinical outcomes. QLFTs were repeated in 196 patients at month 24 and in 165 patients at month 48. Caffeine elimination rate (kelim), antipyrine (AP) clearance (Cl), MEGX concentration, methionine breath test (MBT), galactose elimination capacity (GEC), dual cholate (CA) clearances and shunt, perfused hepatic mass (PHM), and liver and spleen volumes (by single-photon emission computed tomography) were measured. Baseline QLFTs were significantly worse (P = 0.0017 to P < 0.0001) and spleen volumes were larger (P < 0.0001) in the 54 patients who subsequently experienced clinical outcomes. QLFT cutoffs that characterized patients as “low” and “high risk” for clinical outcome yielded hazard ratios ranging from 2.21 (95% confidence interval [CI]: 1.29–3.78) for GEC to 6.52 (95% CI: 3.63–11.71) for CA clearance after oral administration (Cloral). QLFTs independently predicted outcome in models with Ishak fibrosis score, platelet count, and standard laboratory tests. In serial studies, patients with high-risk results for CA Cloral or PHM had a nearly 15-fold increase in risk for clinical outcome. Less than 5% of patients with “low risk” QLFTs experienced a clinical outcome. Conclusion: QLFTs independently predict risk for future clinical outcomes. By improving risk assessment, QLFTs could enhance the noninvasive monitoring, counseling, and management of patients with chronic HCV. (Hepatology 2012)
Human liver cell spheroids in extended perfusion bioreactor culture for repeated-dose drug testing
Authors: Tostões Rui M. , Leite Sofia B. , Serra Margarida , Jensen Janne , Björquist Petter , Carrondo Manuel J. T. , Brito Catarina , Alves Paula M. 
Published: October 2011

Abstract

Primary cultures of human hepatocyte spheroids are a promising in vitro model for long-term studies of hepatic metabolism and cytotoxicity. The lack of robust methodologies to culture cell spheroids, as well as a poor characterization of human hepatocyte spheroid architecture and liver-specific functionality, have hampered a widespread adoption of this three-dimensional culture format. In this work, an automated perfusion bioreactor was used to obtain and maintain human hepatocyte spheroids. These spheroids were cultured for 3–4 weeks in serum-free conditions, sustaining their phase I enzyme expression and permitting repeated induction during long culture times; rate of albumin and urea synthesis, as well as phase I and II drug-metabolizing enzyme gene expression and activity of spheroid hepatocyte cultures, presented reproducible profiles, despite basal interdonor variability (n = 3 donors). Immunofluorescence microscopy of human hepatocyte spheroids after 3–4 weeks of long-term culture confirmed the presence of the liver-specific markers, hepatocyte nuclear factor 4α, albumin, cytokeratin 18, and cytochrome P450 3A. Moreover, immunostaining of the atypical protein kinase C apical marker, as well as the excretion of a fluorescent dye, evidenced that these spheroids spontaneously assemble a functional bile canaliculi network, extending from the surface to the interior of the spheroids, after 3–4 weeks of culture. Conclusion: Perfusion bioreactor cultures of primary human hepatocyte spheroids maintain a liver-specific activity and architecture and are thus suitable for drug testing in a long-term, repeated-dose format. (Hepatology 2012)
Unfolded protein responses in bacteria and mitochondria: A central role for the ClpXP machine
Authors: Truscott Kaye N. , Bezawork‐Geleta Ayenachew , Dougan David A. 
Published: October 2011

AbstractIn the crowded environment of a cell, the protein quality control machinery, such as molecular chaperones and proteases, maintains a population of folded and hence functional proteins. The accumulation of unfolded proteins in a cell is particularly harmful as it not only reduces the concentration of active proteins but also overburdens the protein quality control machinery, which in turn, can lead to a significant increase in nonproductive folding and protein aggregation. To circumvent this problem, cells use heat shock and unfolded protein stress response pathways, which essentially sense the change to protein homeostasis upregulating protein quality control factors that act to restore the balance. Interestingly, several stress response pathways are proteolytically controlled. In this review, we provide a brief summary of targeted protein degradation by AAA+ proteases and focus on the role of ClpXP proteases, particularly in the signaling pathway of the Escherichia coli extracellular stress response and the mitochondrial unfolded protein response. © 2011 IUBMB IUBMB Life, 63(11): 955–963, 2011
Gadofosveset trisodium‐enhanced abdominal perforator MRA
Authors: Zou Zhitong , Kate Lee Hwayoung , Levine Joshua L. , Greenspun David T. , Allen Robert J. , Vasile Julie , Rohde Christine , Prince Martin R. 
Published: October 2011

AbstractPurpose:To compare image quality including the number of perforators visualized, vessel contrast ratios, and vessel sharpness with blood pool and extracellular contrast agents in abdominal perforator flap magnetic resonance angiography (MRA).Materials and Methods:Preoperative perforator flap MRA was performed prone on 64 consecutive patients undergoing breast reconstruction (32 receiving 20 mL gadobenate dimeglumine and 32 receiving 10 mL gadofosveset trisodium) on transverse 3D fat‐suppressed spoiled gradient echo images using high spatial resolution. Image quality was assessed qualitatively on a 4‐point scale. On a computer workstation the number of perforators visualized was counted, arterial, venous, muscle, fat, and abdominal perforator signal intensities were measured to calculate signal intensity and contrast ratios, and vessel sharpness was evaluated.Results:The qualitative image quality score was higher for gadofosveset (2.7) than gadobenate (2.0) and CTA (2.0). The mean number of perforators visualized with gadofosveset was 6.8 on right and 10.4 on left compared to 4.6 on right and 6.6 on left for gadobenate (P < 0.0001). The artery‐to‐fat contrast ratio was comparable, suggesting the difference was not related to magnitude of enhancement. Perforator‐to‐muscle contrast ratio was greater for gadofosveset, 2.3, compared to gadobenate 1.5 (P = 0.002). Vessel sharpness was also greater for gadofosveset (P = 0.006).Conclusion:Perforator MRA image quality including number of perforators visualized, perforator‐to‐muscle contrast, and vessel sharpness is higher with gadofosveset trisodium compared with gadobenate dimeglumine. J. Magn. Reson. Imaging 2012;35:711‐716. © 2011 Wiley Periodicals, Inc.
Ovary‐predominant wnt4 expression during gonadal differentiation is not conserved in the rainbow trout (Oncorhynchus mykiss)
Authors: Nicol Barbara , Guerin Adele , Fostier Alexis , Guiguen Yann 
Published: October 2011

AbstractThe Wnt/β‐catenin pathway is crucial for ovarian differentiation in mammals, and WNT4 is an important protein that regulates this process. While the role of Wnt4 in gonadal differentiation is relatively well characterized in mammals, little is known regarding its role in teleost fish. Therefore, we investigated the potential activity of wnt4 in gonadal differentiation in rainbow trout (Oncorhynchus mykiss), focusing on the teleost and salmonid gene duplications. Phylogenetic and synteny analyses demonstrated that teleost fish possess two wnt4 genes, wnt4a and wnt4b, as a consequence of the teleost‐specific whole‐genome duplication (3R). In rainbow trout, we also identified an additional wnt4 gene, which is a wnt4a paralog that likely resulted from the salmonid‐specific whole‐genome duplication (4R). These two Wnt4a proteins (Wnt4a1 and Wnt4a2) share a high identity (>80%) with other vertebrate Wnt4 proteins, whereas Wnt4b is clearly more divergent (60% identity). During embryogenesis and adulthood, the wnt4a1/2 transcripts were expressed in various tissues, including the ovaries and testes. In contrast, wnt4b expression was restricted to the nervous system, suggesting a sub‐ or a neo‐functionalization of this divergent paralog. During early gonadal differentiation in both males and females, the wnt4a1/2 transcripts were detected in the somatic cells surrounding the germ cells, with a slight sexual dimorphism in favor of males. These results demonstrate that, unlike mammals, rainbow trout do not display an ovary‐predominant wnt4 expression profile during early gonadal differentiation. Mol. Reprod. Dev. 79:51–63, 2012. © 2011 Wiley Periodicals, Inc.
The hp‐d‐adaptive finite cell method for geometrically nonlinear problems of solid mechanics
Authors: Schillinger D. , Düster A. , Rank E. 
Published: October 2011

SUMMARYThe finite cell method (FCM) combines the fictitious domain approach with the p‐version of the finite element method and adaptive integration. For problems of linear elasticity, it offers high convergence rates and simple mesh generation, irrespective of the geometric complexity involved. This article presents the integration of the FCM into the framework of nonlinear finite element technology. However, the penalty parameter of the fictitious domain is restricted to a few orders of magnitude in order to maintain local uniqueness of the deformation map. As a consequence of the weak penalization, nonlinear strain measures provoke excessive stress oscillations in the cells cut by geometric boundaries, leading to a low algebraic rate of convergence. Therefore, the FCM approach is complemented by a local overlay of linear hierarchical basis functions in the sense of the hp‐d method, which synergetically uses the h‐adaptivity of the integration scheme. Numerical experiments show that the hp‐d overlay effectively reduces oscillations and permits stronger penalization of the fictitious domain by stabilizing the deformation map. The hp‐d‐adaptive FCM is thus able to restore high convergence rates for the geometrically nonlinear case, while preserving the easy meshing property of the original FCM. Accuracy and performance of the present scheme are demonstrated by several benchmark problems in one, two, and three dimensions and the nonlinear simulation of a complex foam sample. Copyright © 2011 John Wiley & Sons, Ltd.
Dual boundary method for assembled plate structures undergoing large deflection
Authors: Di Pisa C. , Aliabadi M. H. , Young A. 
Published: October 2011

SUMMARYIn this paper, the dual boundary element method is combined with a multiregion formulation to simulate plate assembly undergoing large deflection. The incremental load approach is used to treat the geometrical nonlinearity, and radial basis functions are used to approximate the derivatives of the large deflection terms. The dual reciprocity method is used to transfer all the domain integrals to the boundary. Once the solution at the boundary is obtained for the assembly, a J −integral for large deflection is implemented to extract the fracture parameters. Copyright © 2011 John Wiley & Sons, Ltd.
Fetal thigh volume by 3D sonography using XI VOCAL: reproducibility and reference range for Brazilian healthy fetuses between 20 and 40 weeks
Authors: Araujo Edward , Cavalcante Rafael Oliveira , Nardozza Luciano Marcondes Machado , Rolo Liliam Cristine , Ruano Rodrigo , de Paula Martins Wellington , Moron Antonio Fernandes 
Published: October 2011

ObjectiveTo provide reference values for fetal thigh volume using three‐dimensional (3D) ultrasound and the eXtended Imaging Virtual Organ Computer‐aided AnaLysis (XI VOCAL) method.MethodsThis is a cross‐sectional study that enrolled 425 healthy pregnant women between the 20th and 40th weeks of gestation. The XI VOCAL was performed along the axial cross‐section in ten sequential areas for the volumetric calculations, having the proximal and distal echogenic diaphysis as references. Second‐degree polynomial regression models, with the determination of percentiles, were created to evaluate the relation between the fetal thigh volume and gestational age (GA). Intraoperator and interoperator reproducibility was evaluated using intraclass correlation coefficient.ResultsThe mean fetal thigh volume varied from 8.00 (3.90–11.90 cm3) to 122.14 cm3 (105.0–153.50 cm3) at 20 and 40 weeks of gestation, respectively. Fetal thigh volume was strongly correlated with gestational age, and the reference values can be obtained by the following mathematical equation: fetal thigh volume (cm3) = 68.70–7.63 × GA + 0.23 × GA2 (R2 = 0.946). The intraoperator and interoperator reproducibility were excellent, with an intraclass correlation coefficient = 1.000 and 0.999, respectively.ConclusionsThe reference range of fetal thigh volume was determined by 3D‐ultrasound using the XI VOCAL method. Copyright © 2011 John Wiley & Sons, Ltd.