bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nanodiamond Tipped and Coated Conical Carbon Tubular Structures
Authors: Chernomordik Boris , Dumpala Santoshrupa , Chen Zhiqiang Q. , Sunkara Mahendra K. 
Published: August 2008

AbstractStudies of diamond nucleation and growth on conical carbon tubular structures show that the nucleation preferentially occurs at the tips, but only occurs on the sidewalls when they are pretreated with diamond or other powder dispersions, forming a nanodiamond coating. The high‐resolution transmission electron microscopy (HRTEM) studies reveal that the diamond nucleation on the sidewalls may proceed through the formation of diamond nuclei within the walls at subsurface damage sites caused during pretreatment. In the case of experiments with low atomic hydrogen conditions, carbon onion structures are observed on the sidewalls but only with pretreatments.
Synthesis and pharmacological evaluation of 3‐(4‐chloro phenyl)‐2‐substituted‐3H‐quinazolin‐4‐ones as analgesic and anti‐inflammatory agents
Authors: Alagarsamy V. , Meena S. , Ramseshu K.V. , Raja Solomon V. , Thirumurugan K. 
Published: August 2008

AbstractA new series of 3‐(4‐chloro phenyl)‐2‐substituted‐3H‐quinazolin‐4‐ones were synthesized by reacting the amino group of 2‐hydrazino‐3‐(4‐chloro phenyl)‐3H‐quinazolin‐4‐one with different aldehydes and ketones. The compounds were investigated for their analgesic activity in albino mice, and for their anti‐inflammatory and ulcerogenic activities in Wistar rats. All test compounds exhibited analgesic and anti‐inflammatory activities. Compound VA2 (2‐(1‐ethylpropylidene‐hydrazino)‐3‐(4‐chloro phenyl)‐3H‐quinazolin‐4‐one) showed moderately more potent analgesic activity and compound VA3 (2‐(1‐methylbutylidene‐hydrazino)‐3‐(4‐chlorophenyl)‐3H‐quinazolin‐4‐one) showed moderately more potent anti‐inflammatory activity when compared with the reference standard, diclofenac sodium. The test compounds showed only mild ulcerogenic side effects when compared with aspirin. Drug Dev Res 69: 226–233, 2008 ©2008 Wiley‐Liss, Inc.
Affinity monolith preconcentrators for polymer microchip capillary electrophoresis
Authors: Yang Weichun , Sun Xiuhua , Pan Tao , Woolley Adam T. 
Published: August 2008

AbstractDevelopments in biology are increasing demands for rapid, inexpensive, and sensitive biomolecular analysis. In this study, polymer microdevices with monolithic columns and electrophoretic channels were used for biological separations. Glycidyl methacrylate‐co‐ethylene dimethacrylate monolithic columns were formed within poly(methyl methacrylate) microchannels by in situ photopolymerization. Flow experiments in these columns demonstrated retention and then elution of amino acids under conditions optimized for sample preconcentration. To enhance analyte selectivity, antibodies were immobilized on monoliths, and subsequent lysozyme treatment blocked nonspecific adsorption. The enrichment capability and selectivity of these affinity monoliths were evaluated by purifying fluorescently tagged amino acids from a mixture containing green fluorescent protein (GFP). Twenty‐fold enrichment and 91% recovery were achieved for the labeled amino acids, with a >25 000‐fold reduction in GFP concentration, as indicated by microchip electrophoresis analysis. These devices should provide a simple, inexpensive, and effective platform for trace analysis in complex biological samples.
Protein determination by microchip capillary electrophoresis using an asymmetric squarylium dye: Noncovalent labeling and nonequilibrium measurement of association constants
Authors: Sloat Amy L. , Roper Michael G. , Lin Xiuli , Ferrance Jerome P. , Landers James P. , Colyer Christa L. 
Published: August 2008

AbstractIn response to a growing interest in the use of smaller, faster microchip (μ‐chip) methods for the separation of proteins, advancements are proposed that employ the asymmetric squarylium dye Red‐1c as a noncovalent label in μ‐chip CE separations. This work compares on‐column and precolumn labeling methods for the proteins BSA, β‐lactoglobulin B (β‐LB), and α‐lactalbumin (α‐LA). Nonequilibrium CE of equilibrium mixtures (NECEEM) represents an efficient method to determine equilibrium parameters associated with the formation of intermolecular complexes, such as those formed between the dye and proteins in this work, and it allows for the use of weak affinity probes in protein quantitation. In particular, nonequilibrium methods employing both μ‐chip and conventional CE systems were implemented to determine association constants governing the formation of noncovalent complexes of the red luminescent squarylium dye Red‐1c with BSA and β‐LB. By our μ‐chip NECEEM method, the association constants Kassoc for β‐LB and BSA complexes with Red‐1c were found to be 3.53×103 and 1.65×105 M−1, respectively, whereas association constants found by our conventional CE‐LIF NECEEM method for these same protein–dye systems were some ten times higher. Despite discrepancies between the two methods, both confirmed the preferential interaction of Red‐1c with BSA. In addition, the effect of protein concentration on measured association constant was assessed by conventional CE methods. Although a small decrease in Kassoc was observed with the increase in protein concentration, our studies indicate that absolute protein concentration may affect the equilibrium determination less than the relative concentration of protein‐to‐dye.
Chaotropic salts: Novel modifiers for the capillary electrophoretic analysis of benzodiazepines
Authors: Su Hsiu‐Li , Lan Min‐Tsu , Lin Kuan‐Wen , Hsieh You‐Zung 
Published: August 2008

AbstractThis paper describes a CE method for analyzing benzodiazepines using the chaotropic salts lithium trifluoromethanesulfonate (LiOTf), lithium hexafluorophosphate (LiPF6), and lithium bis(trifluoromethanesulfonyl)imide (LiNTf2) as modifiers in the running buffer. Although adequate resolution of seven benzodiazepine analytes occurred under the influence of each of the chaotropic anions, the separation efficiency was highest when bis(trifluoromethanesulfonyl)imide (Tf2N−) was the modifier. We applied affinity CE in conjunction with linear analysis to determine the association constants for the formation of complexes between the Tf2N− anion and the benzodiazepines. According to the estimated Gibbs free energies, the interactions between this chaotropic anion and the benzodiazepines were either ion–dipole or ion–induced dipole interactions. Adding chaotropic salts as modifiers into CE buffers is a simple and reproducible technique for separating benzodiazepines.
Peaking cost compensation in Northwest China Power System
Authors: Xie J. , Bai X. , Feng D. , Gan D. 
Published: August 2008

AbstractThe operation scheduling model in Northwest China Power System (NCPS), which is undergoing industry restructuring, is established. The peaking value of generators is identified. Two peaking cost compensation mechanisms for generators are proposed: the first one is based on the theory of cooperative game, the second one based on engineering concept. Some of the characteristics of the suggested game model are analyzed, and several methods for resolving the combinational explosion problem involved in the game‐theoretic computation are described. Two numerical indices for quantifying the peaking capability of generators are proposed, the impacts of generator parameters, load variations, and transmission constraints are investigated. The effectiveness of the proposed methods is showed with the simulation results of a 4‐generator 8‐bus power system and NCPS. Copyright © 2008 John Wiley & Sons, Ltd.
Synaptic localization of GLT‐1a in the rat somatic sensory cortex
Authors: Melone Marcello , Bellesi Michele , Conti Fiorenzo 
Published: August 2008

AbstractGLT‐1a, the major glutamate transporter, plays an important role in both physiological and pathological conditions. Uncertainty regarding its localization in the cerebral cortex prompted us to re‐examine its cellular and subcellular localization in the rat somatic sensory cortex. GLT‐1a detection was sensitive to fixation; in optimal conditions ∼25% of GLT‐1a+ profiles were axon terminals. GLT‐1a/VGLUT1 double‐labeling and pre‐embedding electron microscopy studies showed that ∼50% of GLT‐1a+ profiles were in the vicinity of asymmetric synapses. Using pre‐embedding electron microscopy, we found that ∼70% of GLT‐1a located in the vicinity of asymmetric synapses was astrocytic and ∼30% was neuronal. Post‐embedding immunogold studies showed that the density of gold particles coding for GLT‐1a was much higher in astrocytic processes than in axon terminals, and that in the latter they were never at the active zone. In both astrocytic processes and axon terminals most gold particles were localized in a membrane region extending for about 250 nm from active zone margin, with a peak at 140 nm for astrocytic processes and at 80 for axon terminals. We conclude that, although GLT‐1a is expressed by both astrocytes and axon terminals, astrocytic GLT‐1a predominates at asymmetric synapses, and that the perisynaptic localization of GLT‐1a in cortex is well‐suited to modulate Glu concentrations at the cleft and also to restrict Glu spillover. © 2008 Wiley‐Liss, Inc.
Decreased neural activity in reward circuitry during personal reference in abstinent alcoholics—A fMRI study
Authors: de Greck Moritz , Supady Alexander , Thiemann Rene , Tempelmann Claus , Bogerts Bernhard , Forschner Lukas , Ploetz Klaus v. , Northoff Georg 
Published: August 2008

AbstractTwo of the most striking features in alcoholism are the irresistible craving for alcohol and the proceeding neglect of other activities and pleasures that were formerly relevant. Craving has been investigated extensively and is commonly due to a dysfunctional reward system. The neural basis of the neglect of self‐relevant interests, which can be described as altered personal reference, and its association to the reward system, however, remains unclear. Using fMRI, we investigated neural activity during a paradigm that tested for both reward and personal reference with regard to the same stimuli, i.e., alcoholic and nonalcoholic pictures, in healthy subjects and abstinent alcoholic patients. Alcoholic patients showed slightly reduced signal changes in the brain stem adjacent to ventral tegmental area (VTA) and in the ventromedial prefrontal cortex (VMPFC) during the reward task, while we found no alterations in the right and left ventral striatum (VS). The same regions (VS, VTA, and VMPFC), however, showed reduced signal changes during personal reference with lack of neural differentiation between high and low referenced stimuli in alcoholic patients. In summary, we demonstrate for the first time neurophysiological alterations in reward circuitry during personal reference in alcoholic patients. Our results underline the important role of the reward circuitry during personal reference in the pathophysiology of alcohol addiction. Hum Brain Mapp 2009. © 2008 Wiley‐Liss, Inc.
Maternal deprivation and overnutrition in early postnatal life and their primary prevention: Historical reminiscence of an “ecologic experiment” in Germany
Authors: Dörner Günter , Rodekamp Elke , Plagemann Andreas 
Published: August 2008

AbstractDuring critical developmental periods in early life, altered environmental conditions can lead to pre‐ and early postnatally acquired, life‐long malfunctions and subsequent diseases (Perinatal Programming). Avoiding unfavourable conditions during early development may thus open possibilities of primary prevention.At the beginning of the 21st century, demographic aging and increasing overweight prevalences are two major problems nearly world‐wide. Interestingly, during the second half of the last century, an outstanding “ecologic experiment” has taken place in central Europe, where Germany was divided for four decades into two parts with differing political, economic, social and medical systems, and different approaches towards prevention, especially in early life. Two examples of preventive measures introduced and realized in East Germany and East Berlin until the German reunification were intense breastfeeding promotion and the so‐called “Baby‐Year”, which meant that a mother could stay at home receiving her full salaries for one year after giving birth. Possible outcomes of these measures of primary prevention with effect on demographic aging and overweight risk in the people will be outlined in this essay.
Reproductive, menstrual, and other hormone‐related factors and risk of renal cell cancer
Authors: Zucchetto Antonella , Talamini Renato , Dal Maso Luigino , Negri Eva , Polesel Jerry , Ramazzotti Valerio , Montella Maurizio , Canzonieri Vincenzo , Serraino Diego , La Vecchia Carlo , Franceschi Silvia 
Published: August 2008

AbstractA role of hormone‐related factors in renal cell cancer (RCC) etiology has been hypothesized, but the epidemiological evidence is inconsistent. The present study aimed at evaluating the effect of reproductive, menstrual and other gender‐specific variables on RCC risk among women. This study is part of a larger hospital‐based, case‐control study on RCC risk, conducted in northern, central and southern Italy. Cases were 273 women, below age 80, with histologically confirmed, incident RCC. Controls were 546 women hospitalized for acute, nonneoplastic conditions, frequency‐matched to cases by age and center. Odds ratios (OR) and 95% confidence intervals (CI) were computed using multiple logistic regression models. RCC risk was inversely related to age at first birth (OR = 0.7, 95% CI 0.5–1.0, for ≥ 25 years vs. <25 years). Hysterectomy was found to double RCC risk (OR = 2.3, 95% CI 1.3–4.2). A negative association of borderline‐statistical significance emerged for age at menarche, whereas, no associations were found between RCC risk and parity, menopausal status, age at menopause and use of hormone replacement therapy or oral contraceptives. Our findings give support to a role of hysterectomy in increasing RCC risk without corroborating, however, a major role of female hormone‐related factors. © 2008 Wiley‐Liss, Inc.
Identifying the new Keynesian Phillips curve
Authors: Nason James M. , Smith Gregor W. 
Published: August 2008

AbstractPhillips curves are central to discussions of inflation dynamics and monetary policy. The hybrid new Keynesian Phillips curve (NKPC) describes how past inflation, expected future inflation, and a measure of real aggregate demand drive the current inflation rate. This paper studies the (potential) weak identification of the NKPC under Generalized Method of Moments and traces this syndrome to a lack of higher‐order dynamics in exogenous variables. We employ analytic methods to understand the economics of the NKPC identification problem in the canonical three‐equation, new Keynesian model. We revisit the empirical evidence for the USA, the UK, and Canada by constructing tests and confidence intervals based on the Anderson and Rubin (1949) statistic, which is robust to weak identification. We also apply the Guggenberger and Smith (2008) LM test to the underlying NKPC pricing parameters. Both tests yield little evidence of forward‐looking inflation dynamics. Copyright © 2008 John Wiley & Sons, Ltd.
Learning, forecasting and structural breaks
Authors: Maheu John M. , Gordon Stephen 
Published: August 2008

AbstractWe provide a general methodology for forecasting in the presence of structural breaks induced by unpredictable changes to model parameters. Bayesian methods of learning and model comparison are used to derive a predictive density that takes into account the possibility that a break will occur before the next observation. Estimates for the posterior distribution of the most recent break are generated as a by‐product of our procedure. We discuss the importance of using priors that accurately reflect the econometrician's opinions as to what constitutes a plausible forecast. Several applications to macroeconomic time‐series data demonstrate the usefulness of our procedure. Copyright © 2008 John Wiley & Sons, Ltd.
Bayes estimates of distance‐to‐market: transactions costs, cooperatives and milk‐market development in the Ethiopian highlands
Authors: Holloway Garth , Ehui Simeon , Teklu Amare 
Published: August 2008

AbstractRationalizing non‐participation as a resource deficiency in the household, this paper identifies strategies for milk‐market development in the Ethiopian highlands. The additional amounts of covariates required for positive marketable surplus—‘distances‐to market’—are computed from a model in which production and sales are correlated; sales are left‐censored at some unobserved threshold; production efficiencies are heterogeneous; and the data are in the form of a panel. Incorporating these features into the modeling exercise is important because they are fundamental to the data‐generating environment. There are four reasons. First, because production and sales decisions are enacted within the same household, both decisions are affected by the same exogenous shocks, and production and sales are therefore likely to be correlated. Second, because selling involves time and time is arguably the most important resource available to a subsistence household, the minimum sales amount is not zero but, rather, some unobserved threshold that lies beyond zero. Third, the potential existence of heterogeneous abilities in management, ones that lie latent from the econometrician's perspective, suggest that production efficiencies should be permitted to vary across households. Fourth, we observe a single set of households during multiple visits in a single production year. The results convey clearly that institutional and production innovations alone are insufficient to encourage participation. Market‐precipitating innovation requires complementary inputs, especially improvements in human capital and reductions in risk. Copyright © 2008 John Wiley & Sons, Ltd.
Rough and lonely road to prosperity: a reexamination of the sources of growth in Africa using Bayesian model averaging
Authors: Masanjala Winford H. , Papageorgiou Chris 
Published: August 2008

AbstractThis paper takes a fresh look at Africa's growth experience by using the Bayesian model averaging (BMA) methodology. BMA enables us to consider a large number of potential explanatory variables and sort out which of these variable can effectively explain Africa's growth experience. Posterior coefficient estimates reveal that key engines of growth in Africa are substantially different from those in the rest of the world. More precisely, it is shown that mining, primary exports and initial primary education exerted differential effect on African growth. These results are examined in relation to the existing literature. Copyright © 2008 John Wiley & Sons, Ltd.
Understanding the ring current effects on magnetic shielding of hydrogen and carbon nuclei in naphthalene and anthracene
Authors: Cuesta Inmaculada Garíca , De Merás Alfredo Sánchez , Pelloni Stefano , Lazzeretti Paolo 
Published: August 2008

AbstractThe local response to an external magnetic field normal to the molecular plane of naphthalene and anthracene was investigated via current density and magnetic shielding density maps. The Biot‐Savart law shows that the deshielding caused by π‐ring currents in naphthalene is stronger for α‐ than for β‐protons due to geometrical factors. The shielding tensor of the carbon nuclei in both molecules is strongly anisotropic and its out‐of‐plane component determines the up‐field chemical shift of 13C in nuclear magnetic resonance spectra. The π‐ring currents flowing beyond the C‐skeleton in front of a probe carbon nucleus, and on remote parts of the molecular perimeter, yield positive contributions to the out‐of‐plane component of carbon shielding as big as ≈10–15% of the total values. Near Hartree‐Fock estimates of magnetizability and magnetic shielding at the nuclei fully consistent with the current model are reported. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2009
Conformational selection of protein kinase A revealed by flexible‐ligand flexible‐protein docking
Authors: Huang Zunnan , Wong Chung F. 
Published: August 2008

AbstractProtein kinases have high structural plasticity: their structure can change significantly, depending on what ligands are bound to them. Rigid‐protein docking methods are not capable of describing such effects. Here, we present a new flexible‐ligand flexible‐protein docking model in which the protein can adopt conformations between two extremes observed experimentally. The model utilized a molecular dynamics‐based simulated annealing cycling protocol and a distance‐dependent dielectric model to perform docking. By testing this model on docking four diverse ligands to protein kinase A, we found that the ligands were able to dock successfully to the protein with the proper conformations of the protein induced. By imposing relatively soft conformational restraints to the protein during docking, this model reduced computational costs yet permitted essential conformational changes that were essential for these inhibitors to dock properly to the protein. For example, without adequate movement of the glycine‐rich loop, it was difficult for the ligands to move from the surface of the protein to the binding site. In addition, these simulations called for better ways to compare simulation results with experiment other than using the popular root‐mean‐square deviation between the structure of a ligand in a docking pose and that in experiment because the structure of the protein also changed. In this work, we also calculated the correlation coefficient between protein–ligand/protein–protein distances in the docking structure and those in the crystal structure to check how well a ligand docked into the binding site of the protein and whether the proper conformation of the protein was induced. © 2008 Wiley Periodicals, Inc. J Comput Chem 2009
Comparison of some representative density functional theory and wave function theory methods for the studies of amino acids
Authors: Yu Wenbo , Liang Lei , Lin Zijing , Ling Sanliang , Haranczyk Maciej , Gutowski Maciej 
Published: August 2008

AbstractEnergies of different conformers of 22 amino acid molecules and their protonated and deprotonated species were calculated by some density functional theory (DFT; SVWN, B3LYP, B3PW91, MPWB1K, BHandHLYP) and wave function theory (WFT; HF, MP2) methods with the 6‐311++G(d,p) basis set to obtain the relative conformer energies, vertical electron detachment energies, deprotonation energies, and proton affinities. Taking the CCSD/6‐311++G(d,p) results as the references, the performances of the tested DFT and WFT methods for amino acids with various intramolecular hydrogen bonds were determined. The BHandHLYP method was the best overall performer among the tested DFT methods, and its accuracy was even better than that of the more expensive MP2 method. The computational dependencies of the five DFT methods and the HF and MP2 methods on the basis sets were further examined with the 6‐31G(d,p), 6‐311++G(d,p), aug‐cc‐pVDZ, 6‐311++G(2df,p), and aug‐cc‐pVTZ basis sets. The differences between the small and large basis set results have decreased quickly for the hybrid generalized gradient approximation (GGA) methods. The basis set convergence of the MP2 results has been, however, very slow. Considering both the cost and the accuracy, the BHandHLYP functional with the 6‐311++G(d,p) basis set is the best choice for the amino acid systems that are rich in hydrogen bonds. © 2008 Wiley Periodicals, Inc. J Comput Chem 2009