bluuebunny/crossref_metadata_2025_split huggingface dataset:
Temperature Response of PNIPAM Derivatives at Planar Surfaces: Comparison between Polyelectrolyte Multilayers and Adsorbed Microgels
Authors: Burmistrova Anna , Steitz Roland , von Klitzing Regine 
Published: November 2010

AbstractTwo strategies for the design of thermosensitive coatings based on poly‐N‐isopropyl acrylamide (PNIPAM) derivatives are presented: 1) polyelectrolyte multilayers containing a diblock copolymer with a large PNIPAM block and 2) adsorption of PNIPAM microgels. The multilayers show only a small but irreversible response to the increase of outer temperature due to the strong interdigitation between the charged part and the temperature‐sensitive block, while the adsorbed microgels show a pronounced and reversible response. It will be shown that the microgel number density can be easily controlled at the substrate. The swelling and shrinking of two extremes in density are characterized: densely packed microgels, which are considered as a film, and individual microgels, which are able to swell and shrink also lateral to the surface.
Influence of N‐Alkyl Substituents and Counterions on the Structural and Mesomorphic Properties of Guanidinium Salts: Experiment and Quantum Chemical Calculations
Authors: Butschies Martin , Sauer Sven , Kessler Elena , Siehl Hans‐Ullrich , Claasen Birgit , Fischer Peter , Frey Wolfgang , Laschat Sabine 
Published: November 2010

AbstractA series of N‐4‐(4′‐alkoxybiphenyl)‐N′,N′,N”,N“‐tetramethylguanidinium salts was synthesized with varying alkoxy chain lengths and additional N‐alkyl substituents, each with a number of different counterions. X‐ray crystal‐structure analyses of 1b I, 1b PF6, 2a I, and 4a I reveal bilayer structures in the solid state and, for the 1b and 1b PF6 salts, a hydrogen‐bond‐type connectivity between the guanidinium N‐H group and the anion is found. For the N‐alkyl homologues 2a I and 4a I the anion is still oriented close to the head group, although at a larger distance. Ion pairs are present also in solution, as demonstrated by 1H NMR: the N‐H chemical shift shows a good linear correlation with the radius, and hence the hardness, of the anion. The intramolecular conformational flexibility of 1b I, 2b I, 3b I, and 4b I was studied by temperature‐dependent 1H NMR spectroscopy and discrete activation barriers were determined for rotations about each of the three CN partial double bonds of the guanidinium core. The relative heights of the individual barriers change between the N‐H and the N‐alkylguanidinium salts. A fourth barrier is observed for the rotation about the Nbiphenyl bond. DFT calculations of charge densities show that the positive charge resides primarily on the central carbon atom. Rotational barriers were calculated for N′‐substituted 2‐amino‐1,3‐dimethylimidazolidinium cations as models, and are in qualitatively good agreement with the NMR data. Mesomorphic properties were studied by differential‐scanning calorimetry, polarizing optical microscopy, and X‐ray diffraction (WAXS/SAXS). All liquid‐crystalline guanidinium salts exhibit smectic A mesophases. Clearing temperatures show a linear correlation with the anionic radius. Substitution of the N‐H group with methyl, ethyl, or propyl results in decreasing mesophase widths and a concomitant shrinkage of the layer spacings.
Endothelial Cell Energy Metabolism, Proliferation, and Apoptosis in Pulmonary Hypertension
Authors: Xu Weiling , Erzurum Serpil C. 
Published: November 2010

AbstractPulmonary arterial hypertension (PAH) is a fatal disease characterized by impaired regulation of pulmonary hemodynamics and excessive growth and dysfunction of the endothelial cells that line the arteries in PAH lungs. Establishment of methods for culture of pulmonary artery endothelial cells from PAH lungs has provided the groundwork for mechanistic translational studies that confirm and extend findings from model systems and spontaneous pulmonary hypertension in animals. Endothelial cell hyperproliferation, survival, and alterations of biochemical‐metabolic pathways are the unifying endothelial pathobiology of the disease. The hyperproliferative and apoptosis‐resistant phenotype of PAH endothelial cells is dependent upon the activation of signal transducer and activator of transcription (STAT) 3, a fundamental regulator of cell survival and angiogenesis. Animal models of PAH, patients with PAH, and human PAH endothelial cells produce low nitric oxide (NO). In association with the low level of NO, endothelial cells have reduced mitochondrial numbers and cellular respiration, which is associated with more than a threefold increase in glycolysis for energy production. The shift to glycolysis is related to low levels of NO and likely to the pathologic expression of the prosurvival and proangiogenic signal transducer, hypoxia‐inducible factor (HIF)‐1, and the reduced mitochondrial antioxidant manganese superoxide dismutase (MnSOD). In this article, we review the phenotypic changes of the endothelium in PAH and the biochemical mechanisms accounting for the proliferative, glycolytic, and strongly proangiogenic phenotype of these dysfunctional cells, which consequently foster the panvascular progressive pulmonary remodeling in PAH. © 2011 American Physiological Society.Compr Physiol1:357‐372, 2011.
Functional connectivity and neurological recovery
Authors: Corbetta Maurizio 
Published: November 2010

AbstractModern theories of brain function emphasize the importance of distributed functional networks and synchronized activity within and between networks in mediating cognitive functions. This view highlights the importance of considering brain‐behavior relationships after focsal lesions not only as the result of local structural damage but also as a more widespread alteration of the physiological state of networks connected to the lesion. Recent findings demonstrate coherent activity in large‐scale brain networks not only during task performance, but also, surprisingly, at rest in the absence of stimuli, tasks, or overt responses. Moreover, breakdown of coherent activity at rest, even in regions that are structurally intact, correlates with behavioral deficits and with their recovery after injury. This network perspective is fundamental to understand not only healthy brain function, but also the pathophysiology of brain injuries, mechanisms of functional recovery, and the basis for novel interventions for therapy. © 2010 Wiley Periodicals, Inc. Dev Psychobiol 54:239‐253, 2012.
Effects of maternal breathing rate, psychiatric status, and cortisol on fetal heart rate
Authors: Monk Catherine , Fifer William P. , Myers Michael M. , Bagiella Emilia , Duong Jimmy K. , Chen Ivy S. , Leotti Lauren , Altincatal Arman 
Published: November 2010

AbstractWomen's experiences during pregnancy are predictive of variation in neurobehavioral profiles in their children. Few studies have assessed these relationships during the prenatal period. In 113 women in the 36th –38th gestational week (mean age 26.3 ± 5.4 years), electrocardiogram, blood pressure, respiration, salivary cortisol, and fetal heart rate (HR) were measured during baseline, a psychological challenge (Stroop color–word matching task), and a standardized paced breathing protocol. Subjects underwent the Structured Clinical Interview for DSM‐IV prior to testing and were grouped as: depressed, co–morbid for depression and anxiety, anxiety disorder only, and control. There was a significant main effect of maternal diagnostic group on fetal HR only during the Stroop task: fetuses of women in the co–morbid group had a greater HR increase compared to controls (p < .05). Overall, fetuses showed robust increases in HR during paced breathing (p < .0001), and there was no significant difference by maternal diagnosis. For both tasks, changes in fetal HR were independent of women's concurrent cardiorespiratory activity. Finally, although cortisol was higher in the co‐morbid group (p < .05), across all participants, there was a trend for maternal baseline cortisol to be positively associated with average fetal HR (p = .06). These findings indicate that variation in fetal HR reactivity—an index of emerging regulatory capacities—is likely influenced by multiple acute and chronic factors associated with women's psychobiology. © 2010 Wiley Periodicals, Inc. Dev Psychobiol 53:221–233, 2011.
Ti8O8(OOCR)16, a New Family of Titanium–Oxo Clusters: Potential NBUs for Reticular Chemistry
Authors: Frot Théo , Cochet Sébastien , Laurent Guillaume , Sassoye Capucine , Popall Michael , Sanchez Clément , Rozes Laurence 
Published: November 2010

AbstractThe reactions of titanium alkoxides with a large excess of different carboxylic acids under nonhydrolytic conditions leads to the reproducible formation of well‐defined nano‐building units (NBUs) with the formula [Ti8O8(OOCR)16] [R = C6H5, C(CH3)3, CH3]. The structures of these titanium–oxo–carboxylate clusters have been determined by crossingdifferent characterization techniques and methodologies (single‐crystal X‐ray diffraction, 13C and 1H NMR spectroscopy, and FTIR spectroscopy). These NBUs are obtained in high yields and, since all the alkoxo ligands have been removed by using solvothermal‐synthesis conditions, they present better stability upon hydrolysis than the often reported alkoxo–carboxylate–titanium–oxo clusters [TinO2n–x/2–y/2(OR′)x(OOCR)y] (n ≥ 2; x ≥ 1; y ≥ 1). In addition, the solubility and transferability of these clusters in common solvents can be tuned by selecting the nature of the organic ligand. Moreover, we also report for the first time, a robust post‐modification of the carboxylate ligands by transesterification reactions on the titanium–oxo clusters. These reactions keep the integrity of the octameric titanium–oxo core intact, while completely exchanging the organic shell of the cluster. This family of [Ti8O8(OOCR)16] clusters, which present 16 points of extension, a symmetric shape, and the ability to be post‐modified with conservation of the core structure, can therefore be considered as interesting NBUs to form new metal–organic frameworks.
Allele frequency distribution for D11S1304, D11S1998, and D11S934 and metabolic syndrome in TLGS
Authors: Daneshpour Maryam Sadat , Alfadhli Suad , Houshmand Massoud , Zeinali Sirous , Hedayati Mehdi , Zarkesh Maryam , Azizi Fereidoun 
Published: November 2010

AbstractDifferent variant frequencies may lead to different frequencies of the same variants in individuals with drugs resistance and disease susceptibility at the population level. In this study, the allele frequency of three STRs loci including D11S1304, D11S1998, and D11S934 was analyzed on a representative sample of 563 individuals from the capital city of Tehran. The sample included four different ethnic groups. In this sample, 130 individuals were affected with metabolic syndrome (Mets). Calculated parameters on the whole sample were: allele frequency, polymorphic information content values, observed and expected heterozygosity, discrimination power, matching probability, power of discrimination, power of exclusion, and paternity index. For all markers, no significant deviation from Hardy–Weinberg equilibrium was found in observed allele frequencies except D11S1998. There were no significant differences in the allele frequencies in short, medium and long alleles between the metabolic affected subjects and controls. The most significant findings of this study report allele frequency of some STRs on chromosome 11 for the first time in Iran and the observed differences between subjects affected with Mets as opposed to subjects in the control group.
New Highly Diastereoselective Perkin/Michael Addition Domino Reaction between Homophthalic Anhydride and Aromatic Aldehydes: A Facile Approach to Blue‐Fluorescent Dibenzo[c,h]chromenones
Authors: Bogdanov Milen G. , Mitrev Yavor , Tiritiris Ioannis 
Published: November 2010

AbstractA series of new trans‐11‐aryl‐6‐oxo‐6H‐dibenzo[c,h]chromene‐12‐carboxylic acids has been synthesised through anew Perkin/Michael addition domino reaction between homophthalic anhydride and aromatic aldehydes. The synthesis is straightforward and gives good overall yields by taking into account the concomitant formation of four C–C, C–O and C=C bonds. The structures of the newly synthesised compounds were established by spectroscopic methods (1H NMR, 13C NMR and IR) and X‐ray diffraction analysis, and the fluorescent properties were investigated. A probable reaction mechanism including three proven intermediates is proposed.
From the Decks to the Bridges: Optoelectronics in [2.2]Paracyclophane Chemistry
Authors: Elacqua Elizabeth , MacGillivray Leonard R. 
Published: November 2010

AbstractIn this microreview, we highlight optical properties of [2.2]paracyclophanes (pCps). We demonstrate how the spectroscopic properties that stem from the strained and π‐stacked structure have resulted in pCps being incorporated in materials science and polymer synthesis. As a result of chromophore substitution, internal charge transfer (ICT) between the two rings of the cyclophane core produce frameworks with unique optical properties. Deck‐substituted molecules and polymers have beensynthesized that possess donor and acceptor groups that affect internal charge transfer (ICT). We also demonstrate that bridge‐substituted [2.2]paracylophanes, although not well studied in this context, display unexpected optical properties owing to nonconventional ICT. A highlight is a recent templated solid‐state synthesis that affords a pCp that exhibits dramatic red‐shifted fluorescence.
Synthesis of Fused Oxa‐Aza Spiro Sugars from D‐Glucose‐Derived δ‐Lactone as Glycosidase Inhibitors
Authors: John Pal A. P. , Gupta Preeti , Suman Reddy Y. , Vankar Yashwant D. 
Published: November 2010

AbstractFour conformationally constrained fused oxa‐aza spiro sugars have been synthesized from perbenzylated D‐gluconolactone involving C‐glycosylation of ketoses by using Me3SiCN, ring‐closing metathesis, and diastereoselective dihydroxylation as key steps. Two of the four spiro sugars were found to be highly selective but moderate inhibitors of α‐mannosidase.
Molecular weight determination of high molecular mass (glyco)proteins using CGE‐on‐a‐chip, planar SDS‐PAGE and MALDI‐TOF‐MS
Authors: Müller Roland , Marchetti‐Deschmann Martina , Elgass Helmut , Breiteneder Heimo , Kratzmeier Martin , Allmaier Günter 
Published: November 2010

AbstractThe molecular weights (MW) of seven (glyco)proteins, of which five were plasma‐derived, with MWs higher than 200 kDa were determined with three techniques: CGE‐on‐a‐chip, SDS‐PAGE and MALDI‐TOF‐MS. While the analysis of medium to high MW proteins with SDS‐PAGE was an already well‐established technique, the usefulness of MALDI‐TOF‐MS for the exact MW determination of high mass proteins was only partly described in literature so far. CGE‐on‐a‐chip is the newest of all three applied techniques and was so far not applicable. Therefore, it was not evaluated for high MW (glyco)proteins. All proteins were analyzed under nonreducing as well as reducing conditions. In this work, it was demonstrated that all three described techniques were capable of determining the MW of all high molecular weight (glyco)proteins. The noncommercial CGE‐on‐a‐chip assay allowed for the first time the electrophoretic separation of proteins in the MW range from 14 to 1000 kDa. MW assignment was limited to 500 kDa in the case of SDS‐PAGE and 660 kDa in the case of the high MW CGE‐on‐a‐chip assay. With the proper matrix and sample preparation, analysis with a standard MALDI‐TOF‐MS provided accurate MWs for all high MW proteins up to 1 MDa.
Prediction and validation of sidesway collapse of two scale models of a 4‐story steel moment frame
Authors: Lignos D. G. , Krawinkler H. , Whittaker A. S. 
Published: November 2010

AbstractA research program is summarized in which collapse of a steel frame structure is predicted numerically and the accuracy of prediction is validated experimentally through earthquake simulator tests of two 1:8 scale models of a 4‐story code‐compliant prototype moment‐resisting frame. We demonstrate that (1) sidesway collapse can occur for realistic combinations of structural framing and earthquake ground motion; (2) P−Δeffects and component deterioration dominate behavior of the frame near collapse; (3) prediction of collapse is feasible using relatively simple analytical models provided that component deterioration is adequately represented in the analytical model; and (4) response of the framing system near collapse is sensitive to the history that every important component of the frames experiences, implying that symmetric cyclic loading histories that are routinely used to test components provide insufficient information for modeling deterioration near collapse. Copyright © 2010 John Wiley & Sons, Ltd.
Performance‐based earthquake engineering assessment of a self‐centering, post‐tensioned concrete bridge system
Authors: Lee Won K. , Billington Sarah L. 
Published: November 2010

AbstractHighway bridges in highly seismic regions can sustain considerable residual displacements in their columns following large earthquakes. These residual displacements are an important measure of post‐earthquake functionality, and often determine whether or not a bridge remains usable following an earthquake. In this study, a self‐centering system is considered that makes use of unbonded, post‐tensioned steel tendons to provide a restoring force to bridge columns to mitigate the problem of residual displacements. To evaluate the proposed system, a code‐conforming, case‐study bridge structure is analyzed both with conventional reinforced concrete columns and with self‐centering, post‐tensioned columns using a formalized performance‐based earthquake engineering (PBEE) framework. The PBEE analysis allows for a quantitative comparison of the relative performance of the two systems in terms of engineering parameters such as peak drift ratio as well as more readily understood metrics such as expected repair costs and downtime. The self‐centering column system is found to undergo similar peak displacements to the conventional system, but sustains lower residual displacements under large earthquakes, resulting in similar expected repair costs but significantly lower expected downtimes. Copyright © 2010 John Wiley & Sons, Ltd.
Effects of triclosan on soil microbial respiration
Authors: Butler Emma , Whelan Michael J , Ritz Karl , Sakrabani Ruben , van Egmond Roger 
Published: November 2010

Abstract
The antimicrobial substance triclosan has widespread use in personal care products and can enter the terrestrial environment if sewage sludge is applied to soil. The inhibitory effects of triclosan on basal and substrate-induced respiration (SIR) of three different soils were investigated. Soils were dosed and later redosed with four nominal triclosan concentrations, and respiration rates were measured over time. In each soil, a significant depression in basal respiration was noted after initial dosing, followed by a recovery. The initial extent of respiration inhibition was positively related to the triclosan dose, i.e., respiration was most inhibited at highest triclosan concentration. Differences in respiration inhibition between soils at equivalent dose were inversely correlated with organic matter and clay content, suggesting that the bioavailability of triclosan might have been reduced by sorption to organic carbon or by physical protection in micropores. Substrate-induced respiration was also reduced by the addition of triclosan and subsequently recovered. After redosing with triclosan, basal respiration was enhanced in all soils, suggesting that it was acting as a substrate. However, redosing resulted in SIR inhibition in all treatments above 10 mg triclosan kg−1 in all three soils, although all soils appeared to be more resistant to perturbation than following initial dosing. The present study suggests that triclosan inhibits soil respiration but that a subsequent acclimation of the microbial community occurs. Environ. Toxicol. Chem. 2011;30:360–366. © 2010 SETAC
Use of gene expression, biochemical and metabolite profiles to enhance exposure and effects assessment of the model androgen 17β-trenbolone in fish
Authors: Ekman Drew R , Villeneuve Daniel L , Teng Quincy , Ralston-Hooper Kimberly J , Martinović-Weigelt Dalma , Kahl Michael D , Jensen Kathleen M , Durhan Elizabeth J , Makynen Elizabeth A , Ankley Gerald T , Collette Timothy W 
Published: November 2010

AbstractThe impact of exposure by water to a model androgen, 17β-trenbolone (TRB), was assessed in fathead minnows using an integrated molecular approach. This included classical measures of endocrine exposure such as impacts on testosterone (T), 17β-estradiol (E2), and vitellogenin (VTG) concentrations in plasma, as well as determination of effects on the hepatic metabolome using proton nuclear magnetic resonance spectroscopy. In addition, the rates of production of T and E2 in ovary explants were measured, as were changes in a number of ovarian gene transcripts hypothesized to be relevant to androgen exposure. A temporally intensive 16-d test design was used to assess responses both during and after the TRB exposure (i.e., depuration/recovery). This strategy revealed time-dependent responses in females (little impact was seen in the males), in which changes in T and E2 production in the ovary, as well as levels in plasma, declined rapidly (within 1 d), followed shortly by a return to control levels. Gene expression measurements revealed dynamic control of transcript levels in the ovary and suggested potential mechanisms for compensation during the exposure phase of the test. Proton nuclear magnetic resonance spectroscopy revealed a number of hepatic metabolite changes that exhibited strong time and dose dependence. Furthermore, TRB appeared to induce the hepatic metabolome of females to become more like that of males at both high test concentrations of TRB (472 ng/L) and more environmentally relevant levels (33 ng/L). Environ. Toxicol. Chem. 2011;30:319–329. © 2010 SETAC
Resuspension of polychlorinated biphenyl-contaminated field sediment: release to the water column and determination of site-specific KDOC
Authors: Friedman Carey L , Lohmann Rainer , Burgess Robert M , Perron Monique M , Cantwell Mark G 
Published: November 2010

Abstract
Sediments from the New Bedford Harbor (NBH) U.S. Environmental Protection Agency (U.S. EPA) Superfund site (Massachusetts, USA), contaminated with polychlorinated biphenyls (PCBs), were resuspended under different water column redox conditions: untreated, oxidative, and reductive. The partitioning of PCBs to the overlying water column was measured with polyethylene samplers and compared to partitioning without resuspension. Greater concentrations of total aqueous (freely dissolved + dissolved organic carbon (DOC)-associated) PCBs were found in all resuspended treatments for PCBs with mid-range KOWs, but no difference was observed in total aqueous concentrations among different redox conditions. The magnitude of increased concentrations depended on resuspension time and congener KOW, but ranged from approximately one to eight times those found without resuspension. In a parallel study, DOC was flocculated and removed from smaller-scale NBH sediment resuspensions. In situ KDOCs were determined and used to calculate freely dissolved and DOC-associated fractions of the increase in total aqueous PCB concentrations due to resuspension. The importance of DOC-associated PCBs increased with increasing KOW. In situ KDOCs were approximately one to two orders of magnitude greater than those calculated with a commonly used linear free energy relationship (LFER). The present study demonstrates that resuspension of contaminated sediments releases PCBs to the water column, of which a significant fraction are DOC-associated (e.g., 28, 65, and 90% for PCBs 28, 66, and 110, respectively). Results also imply that site-specific PCB KDOCs are superior to those calculated with generic LFERs. Environ. Toxicol. Chem. 2011;30:377–384. © 2010 SETAC