bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chitosan molecular structure as a function of N‐acetylation
Authors: Franca Eduardo F. , Freitas Luiz C. G. , Lins Roberto D. 
Published: February 2011

AbstractMolecular dynamics simulations have been carried out to characterize the structure and solubility of chitosan nanoparticle‐like structures as a function of the deacetylation level (0, 40, 60, and 100%) and the spatial distribution of the N‐acetyl groups in the particles. The polysaccharide chains of highly N‐deacetylated particles where the N‐acetyl groups are uniformly distributed present a high flexibility and preference for the relaxed two‐fold helix and five‐fold helix motifs. When these groups are confined to a given region of the particle, the chains adopt preferentially a two‐fold helix with ϕ and ψ values close to crystalline chitin. Nanoparticles with up to 40% acetylation are moderately soluble, forming stable aggregates when the N‐acetyl groups are unevenly distributed. Systems with 60% or higher N‐acetylation levels are insoluble and present similar degrees of swelling regardless the distribution of their N‐acetyl groups. Overall particle solvation is highly affected by electrostatic forces resulting from the degree of acetylation. The water mobility and orientation around the polysaccharide chains affects the stability of the intramolecular O3‐HO3(n)···O5(n +1) hydrogen bond, which in turn controls particle aggregation. © 2011 Wiley Periodicals, Inc. Biopolymers 95: 448–460, 2011.
Simultaneous determination of fluoxetine and its major active metabolite norfluoxetine in human plasma by LC‐MS/MS using supported liquid extraction
Authors: Li Yu , Emm Thomas , Yeleswaram Swamy 
Published: February 2011

ABSTRACTA rapid, sensitive and selective bioanalytical method was developed for the simultaneous determination of fluoxetine and its primary metabolite norfluoxetine in human plasma. Sample preparation was based on supported liquid extraction (SLE) using methyl tert‐butyl ether to extract the analytes from human plasma. Chromatography was performed on a Synergi 4 μ polar‐RP column using a fast gradient. The ionization was optimized using ESI (+) and selectivity was achieved by tandem mass spectrometric analysis using MRM functions, m/z 310 → 44 for fluoxetine, m/z 296 → 134 for norfluoxetine and m/z 315 → 44 for fluoxetine‐d5 (internal standard). The method is linear over the range of 0.05–20 ng/mL (using a human plasma sample volume of 0.1 mL) with a coefficient determination of greater than 0.999. The method is accurate and precise with intra‐batch and inter‐batch accuracy (%bias) of <±15% and precision (%CV) of <15% for both analytes. A run time of 4 min means a high throughput of samples can be achieved. To our knowledge, this method appears to be the most sensitive one reported so far for the quantitation of fluoxetine and norfluoxetine and can be used for routine therapeutic drug monitoring or pharmacokinetic studies. Copyright © 2011 John Wiley & Sons, Ltd.
High‐performance liquid chromatographic determination of anti‐ hypertensive drugs on dried blood spots using a fluorescence detector – method development and validation
Authors: Rao R. Nageswara , Bompelli Sravan , Maurya Pawan K. 
Published: February 2011

ABSTRACTA selective and sensitive high‐performance liquid chromatography method with fluorescence detection for simultaneous determination of irbesartan, losartan and valsartan on dried blood spots (DBS) has been developed and validated. It involves solvent extraction of a punch of DBS followed by reversed‐phase liquid chromatography on a Lichrospher® 100 RP‐18e column. Fluorescence detection was performed at 259 and 385 nm as excitation and emission wavelengths, respectively. The detection limits of irbesartan, losartan and valsartan were 1.8, 3.6 and 1.8 ng/mL respectively. The mean recoveries of irbesartan, losartan and valsartan were 98.68, 98.42 and 97.81%, respectively. The mean inter‐day and intra‐day precisions of irbesartan, losartan and valsartan were 2.07 and 1.34%, 1.42 and 1.48%, and 3.20 and 2.15% respectively. The proposed method was simple and rapid. Design of experiments was used to evaluate the robustness of the method. Copyright © 2011 John Wiley & Sons, Ltd.
Bewertung der Umweltverträglichkeit von Bauprodukten im Rahmen von bauaufsichtlichen Zulassungen
Authors: Pawel Angela , Strathmann Brigitte 
Published: February 2011

AbstractNachdem in den letzten Jahren die Auswirkungen von Baumaßnahmen auf das Grundwasser stärker in den Fokus der Öffentlichkeit gerückt sind, wird mittlerweile bei der Erteilung von allgemeinen bauaufsichtlichen Zulassungen für spezielle Bauprodukte eine Bewertung der Umweltverträglichkeit vorgenommen. Da Umweltschutz eine wesentliche Anforderung an Bauprodukte im Rahmen der europäischen Bauproduktenrichtlinie ist, werden auch genormte Bauprodukte zukünftig in dieser Hinsicht stärker überprüft werden müssen. In dem Artikel wird vorgestellt, nach welchem Bewertungsschema das DIBt die Beurteilung der Auswirkungen auf Boden und Grundwasser für welche Bauprodukte vornimmt und welche zukünftige Entwicklung sich bei genormten Bauprodukten abzeichnet.Assessment of the environmental compatibility of constructions products within the scope of technical approvals. During the last years the effects of construction works on groundwater have moved more and more into the public spotlight. An assessment of the environmental compatibility has since then been carried out when granting technical approvals for specific construction products. Since environmental protection is an essential requirement for construction products within the scope of the European Construction Products Directive, in future also standardized construction products will have to be checked much stronger in this respect. This article introduces the assessment scheme according to which DIBt performs the evaluation of the effects on soil and groundwater for which construction products and which future development begins to emerge on standardized construction products.
Bronchoscopic and transthoracic cytology and biopsy for pulmonary nonsmall cell carcinomas: Performance characteristics by procedure and tumor type
Authors: Tochigi Naobumi , Dacic Sanja , Ohori N. Paul 
Published: February 2011

AbstractRecent advances have increased the demand for the accurate diagnosis of pulmonary nonsmall cell carcinoma (NSCLC) rendered by biopsy or cytology. However, precise classification is not possible in all cases. In this study, we investigated the performance characteristics of preresection bronchoscopic and transthoracic procedures for the diagnosis of NSCLC. The pathology files were searched for resected NSCLCs and carcinoid tumors with corresponding preresection cytology and/or biopsy cases. The preresection diagnoses were correlated with the resection diagnosis and the type of bronchoscopic or transthoracic procedure. Among the bronchoscopic procedures, endobronchial/transbronchial biopsy (ETBX) had the highest yield for obtaining a positive (malignant) diagnosis and was the best procedure for obtaining precise classification. For transthoracic procedures, fine‐needle aspiration (FNA) and needle core biopsy (NCB) were similar in providing a positive (malignant) diagnosis; however, NCB was better than FNA in obtaining precise classification. From the perspective of the neoplasms, carcinoid tumors yielded a positive (malignant) specimen with accurate classification most often (e.g., 100% by ETBX). This was followed by squamous cell carcinoma and adenocarcinoma. In contrast, precise classification was not possible for adenosquamous carcinoma, large cell carcinoma, and large cell neuroendocrine carcinoma. Bronchoscopic and transthoracic procedures have different performance characteristics. Furthermore, the diagnostic yield is dependent on the histologic type of the neoplasm. While carcinoid tumors are accurately classified in most cases, some other neoplasms are difficult to diagnose and subclassify due to histologic complexity, poor differentiation, or sampling limitations. Diagn. Cytopathol. 2012. © 2011 Wiley Periodicals, Inc.
Chordoid glioma in suprasellar location with extension into the third ventricle: Smear preparation morphology of a rare tumor
Authors: Ghosal Nandita , Thakar Sumit , Kumaran Sunitha P. , Hegde A. S. 
Published: February 2011

AbstractWe report a rare case of recurrent chordoid glioma in suprasellar region with extension into the third ventricle diagnosed peroperatively. On MRI, a brilliantly contrast enhancing lesion in the suprasellar region extending superiorly into the third ventricle and measuring 2.5 × 3 × 3.5 cm was identified. Patient had a previous history of subtotal removal of the tumor 8 months back and had received 56 Gy of postoperative radiotherapy. On smear preparation the tumor was composed of cells arranged in chords and rows in a myxoid background with sprinkling of lymphocytes. The individual cells were polygonal with moderate amount of faintly eosinophilic cytoplasm with cytoplasmic vacoules in few cells. The nuclei showed fine chromatin with small prominent nucleoli. Paraffin sections confirmed the diagnosis and on immunohistochemistry the tumor cells showed strong positivity for GFAP and focal weak positivity for EMA with low MIB‐1 labeling index (<1%). To the best of our knowledge this is the first documented case of chordoid glioma described on crush cytology. Diagn. Cytopathol. 2012; © 2011 Wiley Periodicals, Inc.
Expression of Epstein‐Barr virus and granzyme B in cytologic smears of histiocytic necrotizing lymphadenitis
Authors: Kim Jung Yeon , Shin Eunah , Kim Hyun‐Jung , Park Kyeongmee 
Published: February 2011

AbstractHistiocytic necrotizing lymphadenitis (HNL) is a non‐neoplastic disease of the lymph nodes that is self‐limiting in its clinical course. In this study, the expression of Epstein‐Barr virus (EBV), granzyme B, and other phenotypic markers of HNL was investigated in fine needle‐aspirated (FNA) cytologic smears obtained from 38 patients with HNL. The smear were subjected to immunohistochemical staining for granzyme B, CD3, CD4, CD8, CD20, and CD68 in addition to in‐situ hybridization for EBV to determine whether marker expression could be correlated with disease pathogenesis. The mean age of 28 female and 10 male patients was 22.8 years. CD8‐positive cytotoxic T cells were noted in 65.0% of the smears (13/20 cases), whereas CD4 and CD68 were rarely observed. Granzyme B reactivity was seen in lymphocytes, especially in apoptotic areas, and in histiocytes, with positive rates of 25.0% (9/36) and 11.1% (4/36), respectively. Most FNA smears showed immunoreactivity to both CD3 and CD20, with a predominance of CD3‐positive cells. In‐situ hybridization for EBV was positive in 22.9% (8/35) of the cases. The immunohistochemical staining and EBV in‐situ hybridization results obtained in bleached FNA smears were similar to those in histologic sections. Overall, our results implicate that even though EBV positivity and granzyme B immunoreactivity are noted in HNL, they do not appear to have any apoptosis‐associated role. Diagn. Cytopathol. 2012. © 2011 Wiley Periodicals, Inc.
Cytomorphology of giant cell glioblastoma: Report of a case and brief review of literature
Authors: Jaiswal Sushila , Vij Mukul , Pandey Rakesh , Jaiswal Awadhesh Kumar , Srivastava Arun Kumar , Behari Sanjay 
Published: February 2011

AbstractGiant cell glioblastoma is a histological variant of glioblastoma that accounts for less than 1% of intracranial tumors and to 5% of glioblastoma. They occur at any age and are likely to affect the younger as well the older age group unlike the conventional glioblastoma multiforme (GBM). They are often located subcortically in the temporal and parietal lobes. Cytological descriptions of giant cell glioblastoma are extremely rare. We describe squash cytomorphology of giant cell glioblastoma of left posterior frontal region in 35‐year‐old male. The squash smears were moderately cellular displaying malignant astrocytic tumor cells disposed in cohesive clusters and dispersed population on a necrotic background. Most striking feature was numerous multinucleated giant cells. We also discuss the differential diagnosis in light of relevant literature. Diagn. Cytopathol.
2012;40:440–443. © 2011 Wiley Periodicals, Inc.
Neural correlates of visual recognition in 3‐month‐old infants: The role of experience
Authors: Moulson Margaret C. , Shannon Robert W. , Nelson Charles A. 
Published: February 2011

AbstractEarly experiences contribute powerfully to the development of neural systems that underlie various perceptual and cognitive abilities in humans. In one of the first studies to systematically control infants' exposure to a familiar object, we examined the effects of controlled experience on the neural correlates of visual recognition in two groups of infants. One group received 1 month of in‐home familiarization to a 3D model of a female face. Another group received 1.5 min of in‐lab familiarization to the 3D model of a female face, creating two conditions that differed in the amount and, importantly, the context of exposure to a familiar stimulus. Following familiarization, event‐related potentials (ERPs) were recorded at 3 months of age while infants viewed pictures of the familiar face and an unfamiliar face. Results demonstrated that while both groups of infants discriminated between the familiar and unfamiliar faces, the pattern of neural processing was reversed for the two groups. Thus, the amount and context of visual exposure altered the neural correlates of recognition processes in young infants. © 2011 Wiley Periodicals, Inc. Dev Psychobiol 53:416–424, 2011.
Analysis of methylene blue and its metabolites in blood by capillary electrophoresis/electrospray ionization mass spectrometry
Authors: Yang Fang , Xia Shifei , Liu Zhencai , Chen Jian , Lin Yonghui , Qiu Bin , Chen Guonan 
Published: February 2011

AbstractA method for the determination of methylene blue (MB) and its metabolites (azure A, azure B and azure C) in rat blood by CE‐electrospray ionization mass spectrometry (CE‐ESI‐MS) was developed in this paper. Different analytical parameters were investigated in detail such as pH and concentration of separation buffer, and ESI‐MS instrumental parameters. Under the optimum conditions, MB and its metabolites were separated and detected in 27.3 min. LODs (defined as S/N=3) of this method were 0.22, 0.25, 0.10 and 0.30 μg/mL for MB, azure A, azure B and azure C, respectively. To get a satisfactory extraction efficiency of MB and its metabolites in rat blood, different extraction solutions were studied. By using this method, MB and its metabolites (azure A, azure B and azure C) were successfully analyzed in rat blood samples.
Biosorption and growth inhibition of wetland plants in water contaminated with a mixture of arsenic and heavy metals
Authors: Park Soyoung , Kang Daeseok , Kim Youngyun , Lee Suk Mo , Chung Yonghyun , Sung Kijune 
Published: February 2011

AbstractThe potential of wetland plants as an onsite biosorbent and a biomonitor for combined pollution of arsenic and four heavy metals from non‐point sources was investigated in this study. Ceratophyllum demersum, Hydrilla verticillata, Hydrocharis dubia, and Salvinia natans were exposed to a water containing mixture of As, Cr, Cu, Pb, and Zn. Growth inhibition and biosorption potential of the wetland plants in artificially contaminated conditions were studied. These contaminants significantly reduced the growth of the plants. The tested wetland plants accumulated appreciable amounts of the contaminants in the following order: Pb>Cr>Cu>Zn>As. H. verticillata showed distinct visual change and a high biosorption factor (BSF) rank for As and heavy metals among the plants used in the study. As an unspecific collector of contaminants, it might be useful as a biomonitor and biosorbent in the As and heavy metal‐contaminated aquatic system.
Bridging the gap between turbulence and larger scales of flow motions in rivers
Authors: Marquis Geneviève A. , Roy André G. 
Published: February 2011

ABSTRACTAlthough flow turbulence in rivers is of critical importance to earth scientists, ecologists and engineers, its relations with larger flow scales are not well understood, thus leaving a fundamental gap in our knowledge. From an analysis of a long time series of the streamwise and vertical flow velocity fluctuations measured in a gravel‐bed river, we show that the signature of the fundamental turbulent flow structures (e.g. ejections and sweeps) is embedded within increasingly larger flow scales in a self‐similar manner. The imbrication of turbulent structures into large flow pulsations of flow acceleration and deceleration covers more than two‐orders of magnitude from a few seconds to nearly 10 minutes. This property is explained by the clustering of turbulent events creating an emergent pattern at larger scales. The size of the larger flow pulsations scales with the spacing of the pools and riffles in the river. This implies a mutual adjustment between turbulence generation mechanisms and long pulsations of flow acceleration and deceleration controlled by the bed morphology. These results bridge a gap in our understanding of flows in rivers and offer a new perspective on the interactions between the turbulent flow with larger scales of flow motion that are critical for sediment transport, habitat selection and fish behaviour. Copyright © 2011 John Wiley & Sons, Ltd.
Confounded by sequencing depth in association studies of rare alleles
Authors: Garner Chad 
Published: February 2011

AbstractNext‐generation DNA sequencing technologies are facilitating large‐scale association studies of rare genetic variants. The depth of the sequence read coverage is an important experimental variable in the next‐generation technologies and it is a major determinant of the quality of genotype calls generated from sequence data. When case and control samples are sequenced separately or in different proportions across batches, they are unlikely to be matched on sequencing read depth and a differential misclassification of genotypes can result, causing confounding and an increased false‐positive rate. Data from Pilot Study 3 of the 1000 Genomes project was used to demonstrate that a difference between the mean sequencing read depth of case and control samples can result in false‐positive association for rare and uncommon variants, even when the mean coverage depth exceeds 30× in both groups. The degree of the confounding and inflation in the false‐positive rate depended on the extent to which the mean depth was different in the case and control groups. A logistic regression model was used to test for association between case‐control status and the cumulative number of alleles in a collapsed set of rare and uncommon variants. Including each individual's mean sequence read depth across the variant sites in the logistic regression model nearly eliminated the confounding effect and the inflated false‐positive rate. Furthermore, accounting for the potential error by modeling the probability of the heterozygote genotype calls in the regression analysis had a relatively minor but beneficial effect on the statistical results. Genet. Epidemiol. 35: 261‐268, 2011. © 2011 Wiley‐Liss, Inc.
A review of advances in flash flood forecasting
Authors: Hapuarachchi H. A. P. , Wang Q. J. , Pagano T. C. 
Published: February 2011

AbstractFlash flooding is one of the most hazardous natural events, and it is frequently responsible for loss of life and severe damage to infrastructure and the environment. Research into the use of new modelling techniques and data types in flash flood forecasting has increased over the past decade, and this paper presents a review of recent advances that have emerged from this research. In particular, we focus on the use of quantitative precipitation estimates and forecasts, the use of remotely sensed data in hydrological modelling, developments in forecasting models and techniques, and uncertainty estimates. Over the past decade flash flood forecast lead‐time has expanded up to six hours due to improved rainfall forecasts. However the largest source of uncertainty of flash flood forecasts remains unknown future precipitation. An increased number of physically based hydrological models have been developed and used for flash flood forecasting and they have been found to give more plausible results when compared with the results of conceptual, statistical, and neural network models. Among the three methods for deciding flash flood occurrence discussed in this review, the rainfall comparison method (flash flood guidance) is most commonly used for flash flood forecasting as it is easily understood by the general public. Unfortunately, no existing model is capable of making reliable flash flood forecasts in urban watersheds even though the incidence of urban flash flooding is increasing due to increasing urbanisation. Copyright © 2011 John Wiley & Sons, Ltd.
Variation in the level of protection afforded to birds and crustaceans exposed to different pesticides under standard risk assessment procedures
Authors: Luttik Robert , Hart Andy , Roelofs Willem , Craig Peter , Mineau Pierre 
Published: February 2011

Abstract
First-tier risk assessment for pesticides is often based on the quotient of the toxicity divided by the predicted environmental concentration or dose. This ratio is compared to a fixed assessment factor (AF) to decide whether the pesticide is to be allowed on the market or whether further research is needed. Often, a high value (e.g., the 90th percentile) is assumed for the predicted environmental concentration, and the lowest available value is chosen to represent toxicity; yet, the real level of protection is not known. Therefore, it is also not known whether the first tier is conservative enough or too conservative. By using 2 large toxicity databases and assuming a log-logistic species sensitivity distribution for each pesticide, the percent of species not covered by the AF is estimated in the scenario, where exposure is at the maximum level allowable in the first tier. In the case of crustaceans, the median estimate of the fraction of species not covered by the AF of 100 in the first-tier scenario is 3.4%, on average, for 72 pesticides. In other words, on average, 3.4% of the crustacean species will be exposed above their median lethal concentration (LC50) and median lethal dose (LD50) value in 10% of receiving surface waters that receive the maximum allowable exposure to an individual pesticide. The estimated level of protection varies widely between pesticides. For 10% of the pesticides, the estimated fraction of species not covered is ≥10% (maximum = 41.4%). For 28% of the pesticides, 99.9% of the species will have the assumed level of protection. For birds, the median estimate of the fraction of species exposed above their median lethal dose for the first-tier scenario (AF = 10) is 3.0% on average, when the AF is applied to the lower of the toxicity values for the 2 standard test species. For 11% of the pesticides, the median estimate is ≥10% (maximum = 15.7%). When the AF is applied instead to the geometric mean of the toxicity values for the 2 standard species, the median estimate of the fraction of species not covered by the AF is increased to 7.4% on average; for 31% of the pesticides, this fraction is ≥10% (maximum = 33.4%). This variation in the level of protection should be considered when defining the assumptions, assessment factors, and decision criteria in regulatory risk assessment. Integr Environ Assess Manag 2011;7:459–465. © 2011 SETAC