bluuebunny/crossref_metadata_2025_split huggingface dataset:
Application of SPE‐HPLC‐DAD and SPE‐TLC‐DAD to the determination of pesticides in real water samples
Authors: Tuzimski Tomasz 
Published: October 2008

AbstractPlanar chromatography with diode array scanning (TLC‐DAD) and high‐performance chromatography with diode array detection (HPLC‐DAD) were used to screen water samples for pesticides. Pesticides were enriched from lake water samples by SPE on C18/SDB‐1, C18, C18 Polar Plus and cyanopropyl (CN) cartridges. The recovery rates were high for all extraction materials except for all pesticides on CN cartridges, for which the values were lower. SPE was used not only for preconcentration of analytes but also for their fractionation. The analytes were eluted first with methanol and then with dichloromethane. Methanol eluates were analysed by HPLC‐DAD, the dichloromethane eluates with TLC‐DAD. The method was validated for precision, repeatability and accuracy. The calibration plots were linear between 0.1 and 50.0 μg/mL for all pesticides, the correlation coefficients, r, were between 0.9992 and 1.000 as determined by HPLC‐DAD. In the TLC experiments, the best fit for the calibration lines was found when the calibration data were analysed using a second‐degree polynomial regression. Calibration plots lay between 0.1 and 17 μg/spot for all pesticides, the correlation coefficients, r, were between 0.9974 and 0.9997 determined by TLC‐DAD. The LOD was between 0.04 and 0.65 μg/spot (TLC‐DAD) and between 0.02 and 3.68 μg/mL (HPLC‐DAD).
De Novo Design of a Bolaamphiphilic Peptide with Only Natural Amino Acids
Authors: Qiu Feng , Chen Yongzhu , Tang Chengkang , Zhou Qinghan , Wang Chen , Shi Ying‐Kang , Zhao Xiaojun 
Published: October 2008

AbstractA new self‐assembling bolaamphiphilic peptide has been designed and synthesized using only natural amino acids. This simple peptide is composed of two lysines connected by 4–8 alanines to maintain the characteristics of the traditional bolaamphiphiles. Based on an irregular secondary structure, it can self‐assemble into nanospheres, nanorods, or nanofibers with lengths up to micrometers. The long nanofibers can be broken into smaller fragments by sonication, however, they could reassemble into nanofibers after incubation. Furthermore, the nanostructures were shown to have considerable thermostability. This new bolaamphiphilic peptide differs from any other self‐assembling peptides or bolaamphiphiles, and possibly provides a new approach to fabricate nanomaterials.magnified image
Effect of Ionic Species on the Structures and Properties of Salt‐Containing PEO/Montmorillonite Nanocomposites
Authors: Stefanescu Eduard A. , Stefanescu Cristina , Negulescu Ioan I. , Daly William H. 
Published: October 2008

AbstractThis contribution describes the preparation and characterization of PEO/montmorillonite nanocomposite gels and films containing various lithium and sodium salts. The objective is to understand how the size and diffusion abilities of different ionic species added to these systems alter the crystallinity of the polymer, and affect the mechanical properties and ionic conductivities of the solid nanocomposites. The network strength of the polymer/clay dispersions influences decisively the crystallinity of the PEO chains and the final layered texture of the solid films. The characteristics of films were investigated using a combination of techniques, such as DSC, DMA, DEA, SEM, SAXS and XRD.magnified image
Spectral assignments and anisotropy data of cellulose Iα: 13C‐NMR chemical shift data of cellulose Iα determined by INADEQUATE and RAI techniques applied to uniformly 13C‐labeled bacterial celluloses of different Gluconacetobacter xylinus strains
Authors: Hesse‐Ertelt Stephanie , Witter Raiker , Ulrich Anne S. , Kondo Tetsuo , Heinze Thomas 
Published: October 2008

AbstractSolid‐state 13C‐NMR spectroscopy was used to characterize native cellulose pellicles from two strains of Gluconacetobacter xylinus (ATCC 53582, ATCC 23769), which had been statically cultivated in Hestrin–Schramm (HS) medium containing fully 13C‐labeled β‐D‐glucose‐U‐13C6 as the sole source of carbon. For both samples, the 13C‐NMR chemical shifts were completely assigned for each 13C‐labeled site of cellulose Iα with the aid of 2D refocused INADEQUATE NMR. To determine the principal chemical shift tensor components, a pulse sequence based on the recoupling of anisotropy information (RAI) was applied at 10 kHz MAS. The detailed 13C tensors of cellulose Iα from different bacterial celluloses are thus available now for the first time, and these results have been compared with previously published data of nonenriched material and with theoretical predictions. Copyright © 2008 John Wiley & Sons, Ltd.
Distinctive clinicopathological associations of amplification of the cortactin gene at 11q13 in head and neck squamous cell carcinomas
Authors: Rodrigo JP , García‐Carracedo D , García LA , Menéndez ST , Allonca E , González MV , Fresno MF , Suárez C , García‐Pedrero JM 
Published: October 2008

AbstractAmplification of the 11q13 region is a prevalent genetic alteration in head and neck squamous cell carcinoma (HNSCC). We investigated the clinical significance of cortactin (CTTN) and cyclin D1 (CCND1) amplification in both malignant transformation and tumour progression. CTTN and CCND1 amplification was analysed by differential and real‐time PCR in a prospective series of laryngeal/pharyngeal carcinomas and archival premalignant tissues. CTTN mRNA and protein expression were respectively determined by real‐time RT‐PCR and immunohistochemistry, and correlated with gene status. Molecular alterations were associated with clinicopathological parameters and disease outcome. CTTN and CCND1 amplifications were respectively found in 75 (37%) and 90 (45%) tumours. Both correlated with advanced disease; however, only CTTN amplification was associated with recurrence and reduced disease‐specific survival (p = 0.0022). Strikingly, CTTN amplification differentially influenced survival depending on tumour site (p = 0.0001 larynx versus p = 0.68 pharynx) and was an independent predictor of reduced survival in the larynx (p = 0.04). CCND1 amplification was detected in early tumourigenesis and increased with the severity of dysplasia. Importantly, CTTN amplification was only found in high‐grade dysplasias that progressed to invasive carcinoma. CTTN gene status strongly correlated with mRNA and protein expression. Furthermore, CTTN overexpression correlated significantly with reduced disease‐specific survival (p = 0.018). Taken together, these data indicate that CTTN may serve as a valuable biomarker to identify patients with laryngeal tumours at high risk of recurrence and poor outcome. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Expression patterns of microRNAs in the chorioamniotic membranes: a role for microRNAs in human pregnancy and parturition
Authors: Montenegro D , Romero R , Kim SS , Tarca AL , Draghici S , Kusanovic JP , Kim JS , Lee DC , Erez O , Gotsch F , Hassan SS , Kim CJ 
Published: October 2008

AbstractMicroRNAs (miRNAs) are involved in the post‐transcriptional regulation of gene expression during development. This study was performed to determine gestational age‐dependent changes in miRNA expression in the chorioamniotic membranes and to assess the significance of miRNAs in human pregnancy and parturition. The expression profile of 455 miRNAs was compared between patients at term without labour (TNL: n = 10), in labour (TL: n = 10), and preterm labour (PTL: n = 10) using microarrays. A total of 39 miRNAs were differentially expressed between term and preterm cases, of which 31 (79.5%) were down‐regulated at term. Expression of ten miRNAs, including miR‐338, differentially expressed between PTL and TL groups was decreased at term. Computational analyses using miRBase Targets have identified PLA2G4B, a phospholipase implicated in parturition, as a putative target of miR‐338. Inhibition of endogenous miR‐338 with anti‐miR‐338 increased the mRNA and protein expression of PLA2G4B in decidual cells. Luciferase assay with reporter constructs confirmed that the suppression of PLA2G4B occurs through binding of miR‐338 to the 3′UTR of PLA2G4B. Interestingly, the expression of Dicer, a key miRNA‐processing enzyme, was markedly decreased at term, particularly with labour in the chorioamniotic membranes. Collectively, the novel findings reported herein strongly suggest that post‐transcriptional regulation of genes by miRNAs, coupled with the changes of miRNA processing machinery in the chorioamniotic membranes, plays a role in pregnancy and parturition. Furthermore, the expression level of Dicer in the chorioamniotic membranes dichotomizes pathological preterm labour and physiological spontaneous labour at term. Published in 2008 by John Wiley & Sons, Ltd.
Recurrent intrathecal methotrexate induced neurotoxicity in an adolescent with acute lymphoblastic leukemia: Serial clinical and radiologic findings
Authors: Brugnoletti Fulvia , Morris E. Brannon , Laningham Fred H. , Patay Zoltán , Pauley Jennifer L. , Pui Ching‐Hon , Jeha Sima , Inaba Hiroto 
Published: October 2008

AbstractSystemic and intrathecal methotrexate (MTX) are integral components of acute lymphoblastic leukemia (ALL) therapy, but can be associated with neurotoxicity. We describe here the case of an adolescent male with T‐cell ALL who developed recurrent episodes of subacute neurotoxicity characterized by slurred speech, emotional lability, and hemiparesis after intrathecal MTX administration. Serial magnetic resonance imaging with diffusion‐weighted imaging showed recurrent areas of restricted diffusion within cerebral hemispheric white matter, which correlated chronologically with the administration of intrathecal therapy and severity of clinical symptoms. Resolution of diffusion abnormalities did not preclude further toxicity and a large lesion could cause persisting symptoms. Pediatr Blood Cancer 2009;52:293–295. © 2008 Wiley‐Liss, Inc.
Levetiracetam for seizures in children with brain tumors and other cancers
Authors: Partap Sonia , Fisher Paul Graham 
Published: October 2008

AbstractChildren with brain tumors and other cancers can suffer from seizures. Unfortunately, most antiepileptic therapies are metabolized by the hepatic cytochrome P450 (CYP) system. Levetiracetam, a newer anticonvulsant, does not undergo CYP metabolism and does not alter the pharmacokinetics of chemotherapy, antiemetics, and corticosteroids, which are metabolized by the liver. We studied 23 patients with cancer and seizures treated with levetiracetam. Over 95% of patients had fewer seizures, with 65.2% becoming seizure free; only one patient experienced an adverse reaction. Levetiracetam is effective and well tolerated in children with brain tumors and other cancers, who are often on multiple enzyme‐inducing drugs. Pediatr Blood Cancer 2009;52:288–289. © 2008 Wiley‐Liss, Inc.
Micro‐ and macrophase separation of thermosetting systems modified with epoxidized styrene‐block‐butadiene‐ block‐styrene linear triblock copolymers and their influence on final mechanical properties
Authors: Ocando Connie , Tercjak Agnieszka , Serrano Elena , Ramos José A , Corona‐Galván Sergio , Parellada M Dolores , Fernández‐Berridi M José , Mondragon Iñaki 
Published: October 2008

AbstractBACKGROUND: The goal of this work was to establish the minimum degree of epoxidation needed to develop nanostructured epoxy systems by modification with poly(styrene‐block‐butadiene‐block‐styrene) (SBS) triblock copolymers epoxidized to several degrees, and also to investigate the effect of polystyrene (PS) content on the final morphologies. By using two SBS copolymers, the influence of the weight ratio of the two blocks on the generated morphologies and mechanical properties was also analysed.RESULTS: Nanostructured thermosets were effectively obtained through reaction‐induced microphase separation of PS blocks from the matrix. A minimum of 27 mol% of epoxidation, which corresponds to 4.8 wt% of epoxidized polybutadiene (PB) units in the overall mixture, was needed to ensure nanostructuring of final mixtures and thus their transparency. Hexagonally ordered nanostructures were achieved for PS contents of around 16–20 wt%, which agrees with our previous results for mixtures with other SBS copolymers with different ratios between blocks. The fracture toughness of the epoxy matrix was improved or at least retained with mixing.CONCLUSION: The degree of epoxidation of PB blocks needed to switch epoxy/SBS mixtures from a macrophase‐separated to a nanostructured state has been established. The generated morphologies in the epoxy systems are mainly dependent on the PS content in the mixture. Copyright © 2008 Society of Chemical Industry
Do built‐in fields improve solar cell performance?
Authors: Green Martin A. 
Published: October 2008

AbstractIntrinsic fields can be built into solar cells by varying the doping level and/or the cell bandgap with potential benefits long recognised. A counteracting effect is that varying the doping or bandgap from the optimum for a particular material system will result in poorer material quality. New solutions are described to the standard semiconductor transport and recombination equations that allow such effects to be incorporated and the impact of these fields on device current and voltage to be assessed. Clear boundaries are found between when built‐in fields are beneficial or deleterious. For the case of doping gradients, built‐in fields decrease both cell current and voltage if carrier lifetime decrease more quickly than as the inverse square of doping; decrease current but can increase voltage if the inverse variation is between linear and square; can improve both if less than linear but only significantly if lifetime varies less than the inverse square root of doping. In the case of a graded bandgap, an optimal field exists as a trade‐off between decreased absorption and increased carrier collection. Copyright © 2008 John Wiley & Sons, Ltd.
Very high efficiency solar cell modules
Authors: Barnett Allen , Kirkpatrick Douglas , Honsberg Christiana , Moore Duncan , Wanlass Mark , Emery Keith , Schwartz Richard , Carlson Dave , Bowden Stuart , Aiken Dan , Gray Allen , Kurtz Sarah , Kazmerski Larry , Steiner Myles , Gray Jeffery , Davenport Tom , Buelow Roger , Takacs Laszlo , Shatz Narkis , Bortz John , Jani Omkar , Goossen Keith , Kiamilev Fouad , Doolittle Alan , Ferguson Ian , Unger Blair , Schmidt Greg , Christensen Eric , Salzman David 
Published: October 2008

AbstractThe Very High Efficiency Solar Cell (VHESC) program is developing integrated optical system–PV modules for portable applications that operate at greater than 50% efficiency. We are integrating the optical design with the solar cell design, and have entered previously unoccupied design space. Our approach is driven by proven quantitative models for the solar cell design, the optical design, and the integration of these designs. Optical systems efficiency with an optical efficiency of 93% and solar cell device results under ideal dichroic splitting optics summing to 42·7 ± 2·5% are described. Copyright © 2008 John Wiley & Sons, Ltd.
Compositional engineering of chemical bath deposited (Zn,Cd)S buffer layers for electrodeposited CuIn(S,Se)2 and coevaporated Cu(In,Ga)Se2 solar cells
Authors: Naghavi N. , Hubert C. , Etcheberry A. , Bermudez V. , Hariskos D. , Powalla M. , Lincot D. 
Published: October 2008

AbstractA comparative study of chemical bath deposition (CBD) of ZnS, CdS, and a mixture of (Cd,Zn)S buffer layers has been carried out on electrodeposited CuIn(S,Se)2 (CISSe) and coevaporated Cu(In,Ga)Se2 (CIGS) absorbers. For an optimal bath composition with the ratio of [Zn]/[Cd] = 25, efficiencies higher than those obtained with CdS and ZnS recipes, both on co‐evaporated CIGS and electrodeposited CISSe, have been obtained independent of the absorber used. In order to better understand the (Cd,Zn)S system and its impact on the increased efficiency of cells, predictions from the solubility diagrams of CdS and ZnS in aqueous medium were made. This analysis was completed by in situ growth studies with varying bath composition by quartz crystal microbalance (QCM). The morphology and composition of the films were studied using scanning electron microscopy (SEM) and X‐ray photoelectron spectra (XPS) techniques. Preliminary XPS studies showed that films are composed of a mixture of CdS and Zn(O,OH) phases and not a pure ternary Cd1 − xZnxS compound. The effect of the [Zn]/[Cd] molar ratio on properties of the corresponding CISSe and CIGS solar cells was investigated by current voltage [J(V)] and capacitance voltage [C(V)] characterizations. The origin of optimal results is discussed. Copyright © 2008 John Wiley & Sons, Ltd.
Comprehensive analysis of advanced solar cell contacts consisting of printed fine‐line seed layers thickened by silver plating
Authors: Pysch D. , Mette A. , Filipovic A. , Glunz S. W. 
Published: October 2008

AbstractThis work presents a detailed analysis of a new two‐layer process to contact industrial solar cells. However, most of the results seem to be transferable to standard screen print paste contacts. The seed layer was created by a pad or screen printer and thickened by light‐induced plating (LIP) of silver. These contact structures were investigated microscopically to gain a better understanding of the observed electrical parameters. A review of the present microscopic contact formation model for flat surfaces is presented. This model was extended and applied to surfaces textured with random pyramids. This analysis has revealed two new types of silver crystallites which can be described by a crystallographic model. The dependence of the silver crystallite density on the surface doping concentration was investigated. Next, the dependence of the contact resistance on the width of the seed layer was measured showing that the contact resistivity increases with a reduction of the seed layer width. These results have been further approved by an analysis of SEM images of wet‐chemically etched contacts examining the density of crystallites and the fraction of removed SiNx layer. Contact resistance RC measurements before and after LIP of silver showed surprisingly a positive influence of the plating process on RC. A detailed microscopical analysis revealed four new possible current flow paths due to the LIP of a conventional contact or a seed layer. The results led to an extension of the existing model for a screen‐printed contact. Copyright © 2008 John Wiley & Sons, Ltd.
Comparing Photovoltaic Capacity Value Metrics: A Case Study for the City of Toronto
Authors: Pelland Sophie , Abboud Ihab 
Published: October 2008

AbstractHourly electric power demand data in Toronto from 2000 to 2006 was analyzed along with coincident, simulated hourly photovoltaic (PV) power generation to quantify PV capacity value on a year‐round basis. Three different methods commonly employed by electric utilities were used to assess PV capacity value, and their results were compared. The first method is the Garver approximation to effective load carrying capability (ELCC), which served as a benchmark for capacity value. The other two methods equate PV capacity value with the capacity factor during “peak demand intervals”: for method 2 the interval includes all hours with loads within a given per cent deviation from the peak load; for method 3, a fixed “on‐peak” interval of 11–17 h in June–August is used. Methods 2 and 3 yielded PV capacity values of about 40%, in agreement with the results of the Garver approximation at low grid penetration. This is considerably higher than the yearly PV capacity factor of about 12%, and is in good agreement with previous studies. Capacity value varies significantly from year to year: for instance, values from method 1 at low grid penetration levels range from 30% (year 2000) to 44% (year 2006). Yearly variations in capacity value appear correlated with variations in the demand summer to winter peak ratio, reflecting the fact that PV capacity value is strongly linked to its capacity to reduce peak demand (“peak shaving”) during the summer. Copyright © 2008 Crown in the right of Canada. Published by John Wiley & Sons, Ltd.
Analysis of the human immune response to vaccinia by use of a novel protein microarray suggests that antibodies recognize less than 10% of the total viral proteome
Authors: Schmid Kara , Keasey Sarah L. , Pittman Phillip , Emerson Ginny L. , Meegan James , Tikhonov Alexander P. , Chen Gengxin , Schweitzer Barry , Ulrich Robert G. 
Published: October 2008

AbstractControl of smallpox by mass vaccination was one of the most effective public health measures ever employed for eradicating a devastating infectious disease. However, new methods are needed for monitoring smallpox immunity within current vulnerable populations, and for the development of replacement vaccines for use by immunocompromized or low‐responding individuals. As a measure for achieving this goal, we developed a protein microarray of the vaccinia virus proteome by using high‐throughput baculovirus expression and purification of individual elements. The array was validated with therapeutic‐grade, human hyperimmune sera, and these data were compared to results obtained from individuals vaccinated against smallpox using Dryvax. A high level of reproducibility with a very low background were apparent in repetitive assays that confirmed previously reported antigens and identified new proteins that may be important for neutralizing viral infection. Our results suggest that proteins recognized by antibodies from all vaccinees constituted <10% of the total vaccinia proteome.
Preface: phys. stat. sol. (c) 5/11
Authors: Lincot Daniel , Hodes Gary , Schmuki Patrik , Symposium Organizers  
Published: October 2008

AbstractThe formation of thin films and nanostructures with unique properties on solid surfaces can be achieved from solutions by chemical or electrochemical routes. These processes named chemical bath deposition, chemical solution deposition, liquid phase impregnation, hydrothermal growth, electrodeposition, and anodic oxidation are based on a common conceptual ground of interfacial reactions at the solid–solution interface. The materials can be semiconductors, oxides, metals, hybrids or nanocomposites in the form of thin films, porous networks, nanorods or nanotubes arrays, grown directly by self‐organization mechanisms or inside templates like porous membranes. In recent years we have followed a remarkable development of these synthesis approaches seeking for advanced applications in electronics, photovoltaics, lasing, sensors, photocatalysis, magnetism, batteries etc.The general objective of the symposium was “Chemical and Electrochemical Synthesis of Advanced Materials and Nanostructures on Solid Surfaces: Growth Mechanisms, Characterizations and Applications”. It was held at the E‐MRS Fall Meeting in Warsaw from 17 to 21 September 2007. The aim of the symposium was to promote exchange between researchers in this field for:(i) improving a common understanding of the growth mechanisms involved in the formation pro‐ cesses, from the molecular to the final structure level, involving interfacial chemical or electrochemical reactions, the influence of solution composition including additives, and the effect of external parameters like illumination,(ii) the advanced characterization and optimization of the properties of the films or nanostructures in relation to the formation conditions,(iii) advanced applications in forefront technologies,(iv) theory and modelling.The present issue assembles papers which were presented during the symposium reflecting such developments, in particular in the field of chalcogenide materials, oxide nanostructures based on electrodeposited ZnO, porous semiconductors prepared by anodic oxidation, metal electrodeposition, and hybrid organic–inorganic materials. They give a general view of some of these recent advances and we hope that they will benefit the readers interested to enter this domain of increasing importance. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)