bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chiral Polymers
Authors: Kakuchi Toyoji , Sakai Ryosuke 
Published: January 2009

AbstractA number of chiral polymers are comprehensively described in this paper. The syntheses and characteristic features of various chiral polymers are introduced according to the origin of their chirality. The structure and synthetic methodology of polymers with a configurational chirality are systematically described, which includes enantiomer‐selective polymerization, asymmetric synthesis polymerization, and chirality induction. Helical polymers are described as one of the main issues in this article. Thus, helix‐sense‐selective polymerization, helicity induction, and chiral amplification are discussed in detail. This article also further includes the function and application of chiral polymers involving polymer‐supported chiral catalyst, chiral stationary phase for high‐performance liquid chromatography, a stimulus‐responsive polymer, and a scaffold for constructing three‐dimensionally well‐defined functionality arrays.
Genetic variation in 5HTTLPR is associated with emotional resilience
Authors: Stein Murray B. , Campbell‐Sills Laura , Gelernter Joel 
Published: January 2009

AbstractEmotional resilience can be defined as the ability to maintain healthy and stable levels of psychological functioning in the wake of stress and trauma. Although genes that contribute to psychopathology (often in interaction with environmental stressors) are being detected with increasing consistency, genes that influence resilience to stress have been less studied. In this study, 423 undergraduate college students completed a psychometrically sound 10‐item self‐report measure of resilience (CDRISC‐10) and provided blood for DNA. Linear and logistic regression analyses were used to model relationships between the serotonin transporter promoter polymorphism (5HTTLPR) and CDRISC‐10 scores and categories, respectively. CDRISC‐10 scores were normally distributed (mean 26.17, SD 5.88 [range 5–40]). In models adjusting for ancestry proportion scores (to mitigate confounding by population stratification) and other covariates, each copy of the “s” allele of 5HTTLPR was associated with ∼1‐point lower CDRISC‐10 score. Each copy of the “s” allele was associated with increased (adjusted OR = 1.53, 95% CI 1.06–2.21, P = 0.024) odds of being in the low resilient category (>1 SD below the mean), compared to being homozygous for the “l” allele. These findings suggest that variation in 5HTTLPR is associated with individual differences in emotional resilience, defined as an individual's ability to withstand and bounce back from stress. This relationship may explain the frequently observed interaction between 5HTTLPR and life stressors in predicting adverse mental health outcomes (e.g., depressive symptoms). Replication is needed, in concert with identification of other genes that influence emotional resilience and related phenotypes. © 2009 Wiley‐Liss, Inc.
Selective Propene Epoxidation on Immobilized Au6–10 Clusters: The Effect of Hydrogen and Water on Activity and Selectivity
Authors: Lee Sungsik , Molina Luis M. , López María J. , Alonso Julio A. , Hammer Bjørk , Lee Byeongdu , Seifert Sönke , Winans Randall E. , Elam Jeffrey W. , Pellin Michael J. , Vajda Stefan 
Published: January 2009

AbstractEpoxidieren leicht gemacht: Subnanometergroße Goldcluster auf amorphem Aluminiumoxid sind ein hoch aktiver und selektiver Katalysator für die Epoxidierung von Propen. Am höchsten ist die Selektivität bei Gasmischungen, die Sauerstoff und Wasser enthalten, sodass der Einsatz von Wasserstoff vermieden werden kann. Ab‐initio‐Dichtefunktionalrechnungen lieferten Informationen über Schlüsselintermediate und Reaktionswege. Demnach beruht die Aktivität des Katalysators auf der Bildung von Propenoxid‐Metallacyclen. Al grün, Au gelb, O rot, C grau.magnified image
Plug‐Based Microfluidics with Defined Surface Chemistry to Miniaturize and Control Aggregation of Amyloidogenic Peptides
Authors: Meier Matthias , Kennedy‐Darling Julia , Choi Se Hoon , Norstrom Eric M. , Sisodia Sangram S. , Ismagilov Rustem F. 
Published: January 2009

AbstractSmall with control: For miniaturization of protein aggregation experiments the interfacial chemistry must be controlled to avoid protein aggregation caused by interfacial adsorption. Plug‐based microfluidics with defined surface chemistry (see schematic picture) can then be used to perform hundreds of aggregation experiments with volume‐limited samples, such as cerebrospinal fluid from mice.magnified image
Efficacy of peritoneal dialysis of tolbutamide in rats under conditions of the plasma unbound fraction being increased
Authors: Makita Takashi , Aiba Tetsuya , Izuwa Yuki , Komori Yukiko , Kawasaki Hiromu , Kurosaki Yuji 
Published: January 2009

AbstractPeritoneal dialysis of a highly protein‐bound compound, tolbutamide, was examined in rats to clarify whether the efficacy of the peritoneal dialysis of such compounds increases proportionally as their unbound fractions increase. As expected, it was shown that the tolbutamide concentration of the peritoneal dialysate rose as the unbound fraction of tolbutamide increased. However, the efficacy of peritoneal dialysis of tolbutamide was proportionally elevated only when the unbound fraction was slightly increased by sulfamethoxazole treatment. When the unbound fraction of tolbutamide was increased 7.8 times by sulfadimethoxine treatment, the dialysis efficacy was increased to only 58% of that expected. This discrepancy between the observed and expected values regarding dialysis efficacy was more marked when experiments were performed in rats with experimentally induced acute renal failure. Pharmacokinetic analysis indicated that the intrinsic dialysis clearance of tolbutamide decreased when its unbound fraction was greatly increased. These findings suggest that peritoneal dialysis may be mediated not only by passive diffusion, but also by concentration‐dependent processes. The efficacy of the peritoneal dialysis of therapeutic compounds may be overestimated if the estimation is based only on their unbound fraction measured under control conditions. Copyright © 2009 John Wiley & Sons, Ltd.
Simple strategy of reactivation of a partially inactivated penicillin g acylase biocatalyst in organic solvent and its impact on the synthesis of β‐lactam antibiotics
Authors: Romero Oscar , Vergara José , Fernández‐Lafuente Roberto , Guisán José Manuel , Illanes Andrés , Wilson Lorena 
Published: January 2009

AbstractSome reactions of organic synthesis require to be performed in rather aggressive media, like organic solvents, that frequently impair enzyme operational stability to a considerable extent. We have studied the option of developing a reactivation strategy to increase biocatalyst lifespan under such conditions, under the hypothesis that organic solvent enzyme inactivation is a reversible process. Glyoxyl agarose immobilized penicillin G acylase and cross‐linked enzyme aggregates of the enzyme were considered as biocatalysts performing in dioxane medium. Reactivation strategy consisted in re‐incubation in aqueous medium of the partly inactivated biocatalysts in organic medium, best conditions of reactivation being studied with respect to dioxane concentration and level of enzyme inactivation attained prior to reactivation. Best results were obtained with glyoxyl agarose immobilized penicillin G acylase at all levels of residual activity studied, with reactivations up to 50%; for the case of a biocatalyst inactivated down to 75% of its initial activity, full recovery of enzyme activity was obtained after reactivation. The potential of this strategy was evaluated in the thermodynamically controlled synthesis of deacetoxycephalosporin G in a sequential batch reactor operation, where a 20% increase in the cumulative productivity was obtained by including an intermediate stage of reactivation after 50% inactivation. Biotechnol. Bioeng. 2009;103: 472–479. © 2009 Wiley Periodicals, Inc.
Automatic relevance determination for multi‐way models
Authors: Mørup Morten , Hansen Lars Kai 
Published: January 2009

AbstractEstimating the adequate number of components is an important yet difficult problem in multi‐way modeling. We demonstrate how a Bayesian framework for model selection based on automatic relevance determination (ARD) can be adapted to the Tucker and CandeComp/PARAFAC (CP) models. By assigning priors for the model parameters and learning the hyperparameters of these priors the method is able to turn off excess components and simplify the core structure at a computational cost of fitting the conventional Tucker/CP model. To investigate the impact of the choice of priors we based the ARD on both Laplace and Gaussian priors corresponding to regularization by the sparsity promoting l1‐norm and the conventional l2‐norm, respectively. While the form of the priors had limited effect on the results obtained the ARD approach turned out to form a useful, simple, and efficient tool for selecting the adequate number of components of data within the Tucker and CP structure. For the Tucker and CP model the approach performs better than heuristics such as the Bayesian information criterion (BIC), Akaikes information criterion (AIC), DIFFIT and the numerical convex hull (NumConvHull) while operating only at the cost of estimating an ordinary CP/Tucker model. For the CP model the ARD approach performs almost as well as the core consistency diagnostic (CorConDiag). Thus, the ARD framework is a simple yet efficient tool for the estimation of the adequate number of components in multi‐way models. A Matlab implementation of the proposed algorithm is available for download at www.erpwavelab.org. Copyright © 2009 John Wiley & Sons, Ltd.
A Homochiral 2D Copper(II) Coordination Framework
Authors: Fielden John , Quasdorf Kyle , Ellern Arkady , Kögerler Paul 
Published: January 2009

AbstractReaction of copper(II) salts with (S)‐phenylethylaminodiacetate [(S)‐peadaa] results in the 2D coordination network (S)‐[Cu(peadaa)]n (space group P21), which displays an unusual Cu···Cu connectivity mode. Solid‐state circular dichroism (CD) indicates a strong interaction between the ligand chiral centre and the metal centres, whereas magnetic measurements show both antiferromagnetic coupling and strong ligand field effects. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Nucleophilic Reactivities of Azulene and Fulvenes
Authors: Kędziorek Mariusz , Mayer Peter , Mayr Herbert 
Published: January 2009

AbstractThe kinetics of the reactions of azulene (1), 6,6‐dimethylfulvene (2), 6‐[4‐(dimethylamino)phenyl]fulvene (3) and 6‐(julolidin‐9‐yl)fulvene (4) with a set of benzhydrylium ions (reference electrophiles) have been investigated in MeCN. The second‐order rate constants for these reactions correlate linearly with the electrophilicity parameters (E) of the benzhydrylium ions. According to the linear free‐enthalpy relationship log k2(20 °C) = s(N + E), the nucleophilicity parameters N and s of the π‐nucleophiles 1–4 were determined and compared with those of other types of nucleophiles. Azulene (1, N = 6.66) is about 10 times more nucleophilic than N‐methylpyrrole and comparable to 2‐methylindole. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Ion‐Selective Organic Electrochemical Junction Transistors Based on Poly(3,4‐ethylenedioxythiophene) Doped with Poly(styrene sulfonate)
Authors: Mousavi Zekra , Ekholm Andréas , Bobacka Johan , Ivaska Ari 
Published: January 2009

AbstractIon‐selective organic electrochemical junction transistors (IS‐OEJTs) were prepared and their performance was studied for the detection of potassium, calcium, and silver ions. In this kind of sensors the conducting polymer poly(3,4‐ethylenedioxythiophene) (PEDOT) doped with poly(styrene sulfonate) (PSS), PEDOT : PSS, is utilized for transduction of chemical information to electronic information in the solid state. In order to achieve selectivity, the channel region of the transistors was coated with ionophore‐based polymeric membranes.
Seismic evaluation of 1940s asymmetric wood‐frame building using conventional measurements and high‐definition laser scanning
Authors: Mosalam Khalid M. , Takhirov Shakhzod M. , Hashemi Alidad 
Published: January 2009

AbstractThis study presents results from shake table experiments of a wood‐frame building conducted at the University of California, Berkeley. A 13.5‐ft × 19.5‐ft two‐story wood‐frame building representing San Francisco 1940s design of a residential building with a garage space on the first story (house‐over‐garage) was tested. The test building was subjected to scaled ground motion based on Los Gatos record from Loma Prieta 1989 earthquake. The strong motion time history was scaled to match design spectra of a site in Richmond district of San Francisco. The test results demonstrated the seismic vulnerability of the test building due to soft story mechanism and significant twisting when shaken in two horizontal directions. In addition to conventional instrumentation for measuring acceleration and position of selected points of the test building, high‐definition laser scanning technology was employed to assess global and local anomalies of the building after the shake table tests. The analysis conducted in this study showed very good correlation between conventional data recorded from position transducers and the laser scans. These laser scans expanded limits of conventional data at discrete points and allowed analyzing the whole building after shaking. Copyright © 2009 John Wiley & Sons, Ltd.
A comparision of interpolation methods for producing digital elevation models at the field scale
Authors: Erdogan Saffet 
Published: January 2009

AbstractDigital elevation models have been used in many applications since they came into use in the late 1950s. It is an essential tool for applications that are concerned with the Earth's surface such as hydrology, geology, cartography, geomorphology, engineering applications, landscape architecture and so on. However, there are some differences in assessing the accuracy of digital elevation models for specific applications. Different applications require different levels of accuracy from digital elevation models. In this study, the magnitudes and spatial patterning of elevation errors were therefore examined, using different interpolation methods. Measurements were performed with theodolite and levelling. Previous research has demonstrated the effects of interpolation methods and the nature of errors in digital elevation models obtained with indirect survey methods for small‐scale areas. The purpose of this study was therefore to investigate the size and spatial patterning of errors in digital elevation models obtained with direct survey methods for large‐scale areas, comparing Inverse Distance Weighting, Radial Basis Functions and Kriging interpolation methods to generate digital elevation models. The study is important because it shows how the accuracy of the digital elevation model is related to data density and the interpolation algorithm used. Cross validation, split‐sample and jack‐knifing validation methods were used to evaluate the errors. Global and local spatial auto‐correlation indices were then used to examine the error clustering. Finally, slope and curvature parameters of the area were modelled depending on the error residuals using ordinary least regression analyses. In this case, the best results were obtained using the thin plate spline algorithm. Copyright © 2009 John Wiley & Sons, Ltd.
The application of caesium‐137 measurements to investigate floodplain deposition in a large semi‐arid catchment in Queensland, Australia: a low‐fallout environment
Authors: Amos Kathryn J. , Croke Jacky C. , Timmers Heiko , Owens Philip N. , Thompson Celia 
Published: January 2009

AbstractFloodplains comprise geomorphologically important sources and sinks for sediments and associated pollutants, yet the sedimentology of large dryland floodplains is not well understood. Processes occurring on such floodplains are often difficult to observe, and techniques used to investigate smaller perennial floodplains are often not practical in these environments. This study assesses the utility of 137Cs inventory and depth‐profile techniques for determining relative amounts of floodplain sedimentation in the Fitzroy River, northeastern Australia; a 143 000 km2 semi‐arid river system. Caesium‐137 inventories were calculated for floodplain and reference location bulk soil cores collected from four sites. Depth profiles of 137Cs concentration from each floodplain site and a reference location were recorded. The areal density of 137Cs at reference locations ranged from 13 to 978 Bq m–2 (0–1367 Bq m–2 at the 95% confidence interval), and the mean value ± 2 (standard error of the mean) was 436 ± 264 Bq m–2, similar to published data from other Southern Hemisphere locations. Floodplain inventories ranged from 68 to 1142 Bq m–2 (0–1692 Bq m–2 at the 95% confidence interval), essentially falling within the range of reference inventory values, thus preventing calculation of erosion or deposition. Depth‐profiles of 137Cs concentration indicate erosion at one site and over 66 cm of deposition at another since 1954. Analysis of 239+240Pu concentrations in a depositional core substantiated the interpretation made from 137Cs data, and depict a more tightly constrained peak in concentration. Average annual deposition rates range from 0 to 15 mm. The similarity between floodplain and reference bulk inventories does not necessarily indicate a lack of erosion or deposition, due to low 137Cs fallout in the region and associated high measurement uncertainties, and a likely influence of gully and bank eroded sediments with no or limited adsorbed 137Cs. In this low‐fallout environment, detailed depth‐profile data are necessary for investigating sedimentation using 137Cs. Copyright © 2009 John Wiley & Sons, Ltd.
Storage of sediment‐associated heavy metals along the channelized Odra River, Poland
Authors: Ciszewski Dariusz , Turner Jonathan 
Published: January 2009

AbstractThe importance of long‐term storage of heavy metals in groyne fields, functioning over 150 years, is investigated for the River Odra (Oder), western Poland. Construction of groynes along the Odra preceded rapid development of heavy industrialization in the largest coal mine districts in Poland and the Czech Republic that resulted in persistent riverine pollution. The 187 km long Middle Odra reach was repeatedly channelized from the first half of the eighteenth century to the turn of the twentieth century, during which time partially filled groyne fields were dissected by new bank lines and groyne systems, with older groyne fields partially keyed into the floodplain. Consequently, concentrations of zinc, lead, cadmium, and copper within historically deposited groyne field sediments exceed local geochemical background levels by more than 60, 40, 15 and 10 times, respectively. Sediments contaminated with heavy metals occur within three distinctive geomorphic zones: zone I is up to 250 m wide and furthest from the present channel, comprising decimeter‐thick polluted sediments, overlying eighteenth century sand and gravel bars; zone II represents the former nineteenth century groyne fields, with widths between 10 and 100 m, filled with as much as 3 m of polluted sediments; zone III represents the twentieth century groyne fields, which are several to a dozen metres wide and filled with polluted sediments averaging depths of more than 2 m. This investigation indicates that large and extensive sediment quantities of moderately polluted sediments are stored immediately along the banks of the River Odra. These sediments could be a significant secondary pollution source and therefore careful maintenance of contemporary bank protection structures is required. Copyright © 2009 John Wiley & Sons, Ltd.
Labeling, biodistribution and evaluation of [125I] gemcitabine: a potential agent for tumor diagnosis and radiotherapy
Authors: El‐Kawy O. A. , Hashem A. M. , Amin M. A. , El‐Wetery A. S. 
Published: January 2009

AbstractIn this study, the optimization of gemcitabine labeling with iodine‐125 and its biological evaluation are described. Gemcitabine was labeled via direct electrophilic substitution using chloramine‐T as an oxidizing agent. The optimum amounts of reactants were 75 µg gemcitabine, 75 µg chloramine‐T and 18 MBq carrier‐free Na125I. The labeled gemcitabine was stable for more than 20 h. Results of the in vivo evaluation revealed that the new tracer, [125I] gemcitabine, tends to localize in tissues with high proliferation rate with preferential accumulation in cancerous tissues. Imaging should be carried at 2‐h postinjection. The in vitro cell growth inhibition assay showed that the effect of [125I] gemcitabine was stronger than the effect of tenfold cold gemcitabine, which strongly suggested that its cytotoxicity was mainly due to radiotoxicity rather than chemotherapeutic activity. The binding assay revealed that [125I] gemcitabine uptake by the Ehrlich cells was high and that it bound well to DNA where the decay of the radionuclide introduced lethal irreversible double‐strand breaks. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis of [14C] labeled 2‐methoxypyrimidine‐5‐carboxylic acid
Authors: Murthy Akula , Ullas Giliyar 
Published: January 2009

AbstractA versatile method for 14C labeling of 2‐methoxypyrimidine‐5‐carboxylic acid at the 2‐position has been developed after encountering difficulties with traditional approaches to label the carboxyl function. The method developed can also be used for 14C labeling other positions of the pyrimidine ring system. Copyright © 2009 John Wiley & Sons, Ltd.
Survival of E. coli O157:H7 during manufacture of dry‐cured Westphalian ham surface‐treated with allyl isothiocyanate or hot mustard powder
Authors: Graumann Gary H , Holley Richard A 
Published: January 2009

AbstractBACKGROUND: Escherichia coli O157:H7 can survive commercial manufacture of some uncooked fermented meats. External application of microencapsulated allyl isothiocyanate (AIT) or hot (non‐deheated) yellow mustard powder was used to inactivate the pathogen during dry‐cured Westphalian ham manufacture.RESULTS: Within 45/80 days, E. coli O157:H7 numbers were reduced 5 log10 CFU g−1 by 400 µg kg−1 AIT or 60 g kg−1 mustard powder, but 80 days were required in the untreated control. Mustard powder but not AIT reduced numbers of lactic acid bacteria and staphylococci. Mustard powder or ≥ 300 µg kg−1 AIT inhibited yeasts and moulds but did not affect ham pH or water activity.CONCLUSION: The commercial Westphalian ham process without AIT or mustard powder treatment was validated capable of reducing E. coli O157:H7 5 log10 CFU g−1. Surface treatments with ≥ 300 µg kg−1 microencapsulated AIT or 60 g kg−1 yellow mustard powder reduced the time required for this reduction by 40–50%. AIT volatility from microcapsules or hot mustard powder during application of these compounds may restrict their use in production facilities. Copyright © 2009 Society of Chemical Industry