bluuebunny/crossref_metadata_2025_split huggingface dataset:
AuI‐Catalyzed Intramolecular Cyclization of 2‐Alkenylphenyl Carbonyl Compounds: Exploring the Oxophilic Lewis Acidity of AuI Species
Authors: Jagdale Arun R. , Youn So Won 
Published: March 2011

AbstractA AuI‐catalyzed intramolecular cyclization reaction of 2‐alkenylphenyl carbonyl compounds to afford a variety of indene, indenol, and indanone ring systems was developed. In this process, AuI serves to activate the carbonyl group of β‐keto esters, aldehydes, and ketones, preferentially exhibiting oxophilicity in the presence of C–C multiple bonds. Furthermore, β‐keto esters could participate as the electrophilic partner in reactions with carbon nucleophile such as alkenes.
Isotopic analysis of water sources of mountainous plant uptake in a karst plateau of southwest China
Authors: Rong Li , Chen Xi , Chen Xunhong , Wang Shijie , Du Xuelian 
Published: March 2011

AbstractEcosystem in the karst region of southwest China is very fragile due to a very limited amount of water storage for plant uptake in the thin and rocky soils underlain by rock fractures. Plants in these karst regions are thought to take water from the soils and shallow fractured rock zone (subcutaneous zone) as well. However, the role of subcutaneous water in maintaining karst vegetation remains unclear, and proportions of the water sources for plant uptake in different environment conditions are unknown. In this study, five typical species of plants at two sites were selected in a karst plateau of Qingzhen, central Guizhou Province of China. Proportions of the possible water sources contributed for the plant uptake from two soil layers and subcutaneous zone were determined on the basis of δD and δ18O values of plant stem water, soil water and subcutaneous water. The analysis reveals that most plants take water from the soil layers and the subcutaneous zone as well, but proportions of these water contributions for plant uptake vary seasonally and depend on site‐specific conditions and plant species. Plant uptake of the subcutaneous water for all species averages less than 30% of the total monthly amount in June and September, compared with more than 60% in dry December. Plants tend to take a larger proportion of water from the upper soil layer at the bush site than at the forest site in June and September (63 vs 28% in July; 66 vs 54% in September for all species in average). In December, however, 98% of water is taken from the subcutaneous zone at the bush site which is much greater than 68% at the forest site. Compared to deciduous arbor, evergreen shrub takes a greater proportion of subcutaneous water in the December drought. Copyright © 2011 John Wiley & Sons, Ltd.
A practical estimation of Clark IUH parameters using root selection and linear programming
Authors: Seong Kee‐Won , Lee Yong‐Hak 
Published: March 2011

AbstractThe values of the parameters of the Clark instantaneous unit hydrograph (IUH) are often relying on the subjective decision of the researcher, which leads to large variations of their values. Therefore, an objective method minimizing the subjective judgement in the IUH modelling procedure while providing a reduced range of acceptable values is proposed. The proposed method uses a basin average IUH to mitigate the robustness problem of the Clark IUH parameters. Using linear system theory, the z‐transform is applied to the average IUH and then the IUH polynomial is factored into the recession and time‐area curve (TAC) components based on a convolution relation between the Clark IUH parameters. During this calculation, the root selection method was adopted to verify the storage coefficient R from the recession component and a linear programming technique was applied for determining the TAC for the basin of interest. The Wi River basin was used to test the applicability of the proposed method. The results showed that the components of a single reservoir and the TAC for Clark IUH were separated effectively, and acceptable values for the parameters were obtained. Copyright © 2011 John Wiley & Sons, Ltd.
Application of snowmelt runoff model for water resource management
Authors: Butt Mohsin Jamil , Bilal Muhammad 
Published: March 2011

AbstractSnow‐covered areas (SCAs) are the fundamental source of water for the hydrological cycle for some region. Accurate measurements of river discharge from snowmelt can help manage much needed water required for hydropower generation and irrigation purposes. This study aims to apply the snowmelt runoff model (SRM) in the Upper Indus basin by the Astore River in northern Pakistan for the years 2000 to 2006. The Shuttle Radar Topographic Mission (SRTM) data are used to generate the Digital Elevation Model (DEM) of the region. Various variables (snow cover depletion curves (SCDCs), temperature and precipitation) and parameters (degree‐day factor, recession coefficient, runoff coefficients, time lag, critical temperature and temperature lapse rate) are used as input in the SRM. However, snow cover data are direct and an important input to the SRM. Satellite data from the Moderate Resolution Imaging Spectroradiometer (MODIS) are used to estimate the SCA. Normalized difference snow index (NDSI) algorithm is applied for snow cover mapping and to differentiate snow from other land features. Nash–Sutcliffe coefficient of determination (R2) and volume difference (DV) are used for quality assessment of the SRM. The results of the current research show that for the study years (2000–2006), the average value of R2 is 0·87 and average volume difference DV is 1·18%. The correlation coefficient between measured and computed runoff is 0·95. The results of the study further show that a high level of accuracy can be achieved during the snowmelt season. The simulation results endorse that the SRM in conjunction with MODIS snow cover product is very useful for water resource management in the Astore River and can be used for runoff forecasts in the Indus River basin in northern Pakistan. Copyright © 2011 John Wiley & Sons, Ltd.
Enhancement of vascularization and granulation tissue formation by growth factors in human platelet‐rich plasma‐containing fragmin/protamine microparticles
Authors: Takikawa Megumi , Nakamura Shin‐Ichiro , Nakamura Shingo , Nambu Masaki , Ishihara Masayuki , Fujita Masanori , Kishimoto Satoko , Doumoto Takashi , Yanagibayashi Satoshi , Azuma Ryuichi , Yamamoto Naoto , Kiyosawa Tomoharu 
Published: March 2011

AbstractThe purpose of this study was to evaluate effects of human platelet‐rich plasma (PRP)‐containing fragmin/protamine microparticles (F/P MPs) as a protein carrier on neovascularization and granulation tissue formation. Frozen and thawed PRP contains high concentrations of various growth factors (GFs) and F/P MPs effectively adsorb those GFs. Human microvascular endothelial cells (MVECs) and dermal fibroblast cells (DFCs) were optimally grown in medium containing 4% PRP and the addition of F/P MPs significantly maintained and protected the proliferative activity of PRP incubated at 37°C for more than 10 days. When PRP‐containing F/P MPs were subcutaneously injected into the back of mice, significant neovascularization was induced near the injected site with enhanced filtration of inflammatory cells from day 3 to day 30, compared with controls (injections of PRP, F/P MPs, and saline). Both PRP‐containing F/P MPs and PRP alone induced significant formation of granulation tissue at the injected site. However, thickness of induced granulation tissues was well maintained for 30 days only in PRP‐containing F/P MP‐injected group. Those bound GFs may be gradually diffused and released from F/P MPs in vitro and in vivo. Thereby, PRP‐containing F/P MPs offer significantly higher inductions of vascularization and fibrous tissue formation in vivo than PRP alone. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2011.
Effects of dilute acid pretreatment on enzyme saccharification of wheat stubble
Authors: Vancov Tony , McIntosh Shane 
Published: March 2011

AbstractBACKGROUND: Prehydrolysis of wheat stubble using moderate temperatures and dilute acid strength is an effective means for solubilizing hemicellulose fractions and improving cellulose hydrolysis. Variation in prehydrolysis parameters (temperature, time, and acid strength) and enzymatic saccharification conditions were examined for conversion of wheat stubble into fermentable sugars.RESULTS: Elevating temperature and acid strength maximized sugar release in prehydrolysate liquors. The optimal conditions of 2.0% H2SO4/60 min/121 °C effectively solubilized 79% of the available hemicellulose. Production of inhibitory hydrolysis and degradation products such as acetic acid and levulinic acid, were detected at levels of 3.4 g L−1 and 0.64 g L−1, respectively. Sugar yields in prehydrolysate and saccharified liquors were found to increase with treatment severity. Temperature had the greatest impact on sugar release, followed by acid concentration and time. Optimizing prehydrolysis conditions at 1.0% H2SO4/90 min/121 °C, produced a 3.2‐fold improvement in cellulose hydrolysis with recoveries approaching 82%. The addition of β‐glucosidase and xylanase to the cellulase preparations assisted monomeric sugar release.CONCLUSION: Although treatment conditions for hemicellulose and cellulose hydrolysis differ, the study's findings suggest a good degree of overlap and process flexibility which should permit high recovery of pentose and hexose sugars. Copyright © 2011 Society of Chemical Industry
Ultrafiltration and nanofiltration membranes applied to the removal of the pharmaceuticals amoxicillin, naproxen, metoprolol and phenacetin from water
Authors: Javier Benitez F. , Acero Juan L. , Real Francisco J. , Roldán Gloria , Rodriguez Elena 
Published: March 2011

AbstractBACKGROUND: In the removal of pharmaceuticals present in aquatic systems by membrane processes, some important issues must be explored in order to obtain a better knowledge of the global process. Among these issues, a better understanding of the influences of the operating parameters on the membrane flux, an analysis of membrane resistances and fouling, and determination of the removal of specific substances, must be studied.RESULTS: Four selected pharmaceuticals (amoxicillin, naproxen, metoprolol and phenacetin) were subjected to ultrafiltration (UF) and nanofiltration (NF) processes for their removal from several water matrices. The determined permeate fluxes at the steady state were affected by the main operating conditions: molecular weight cut‐off (MWCO) of the membrane, transmembrane pressure TMP, cross‐flow velocity and temperature. The retention coefficients with the UF membranes followed the sequence naproxen > metoprolol > amoxicillin > phenacetin, and with the NF membranes, followed the trend: amoxicillin > naproxen > metoprolol > phenacetin, due to the role of other mechanisms such as size exclusion and electrostatic repulsion. In the case of the selected water matrices, the retention coefficient was referred to some quality parameters (total organic carbon, chemical oxygen demand and absorbance at 254 nm), leading to moderate (UF) or high (NF) removals of the organic matter content.CONCLUSIONS: The NF CK membrane achieved the highest retention of these pharmaceuticals (excepting phenacetin), and provided retentions for quality parameters around 80% in the four water systems tested. Copyright © 2011 Society of Chemical Industry
Growth kinetics and lipid production using Chlorella vulgaris in a circulating loop photobioreactor
Authors: Sasi Divya , Mitra Pranabendu , Vigueras Andrea , Hill Gordon A. 
Published: March 2011

AbstractBACKGROUND: Compared with agriculture, microalgae culture promises to be a novel way of producing lipids for both food consumption and transportation fuel (biodiesel) purposes while using a minimal amount of land area. A circulating loop photobioreactor has been used to study the growth kinetics and lipid yield of Chlorella vulgaris growing on carbon dioxide as the sole source of carbon.RESULTS: Because of high photosynthetic active radiation (PAR) fluxes, C. vulgaris was observed to grow in exponential mode. The highest growth rate achieved was 0.049 h−1 at the optimum growth conditions of 71.8 mW L−1 PAR density, 10% CO2 (v/v) in air and with an applied 8 h dark phase. The microalgae was observed to grow in a Monod fashion with a PAR density saturation coefficient of 2.8 mW L−1. Light intensity showed the potential to significantly increase lipid yield, which reached a maximum of 30% (by mass) of cell dry weight.CONCLUSION: The circulating loop photobioreactor is a low‐cost bioreactor technology capable of culturing photosynthetic microalgae at high PAR densities and with uniform mixing and lighting. C. vulgaris is able to grow exponentially in this bioreactor and produce lipids at concentrations up to 30% by cell dry weight. Copyright © 2011 Society of Chemical Industry
Different process configurations for bioethanol production from pretreated olive pruning biomass
Authors: Manzanares Paloma , Negro Maria Jose , Oliva Jose Miguel , Saéz Felicia , Ballesteros Ignacio , Ballesteros Mercedes , Cara Cristobal , Castro Eulogio , Ruiz Encarnacion 
Published: March 2011

AbstractBACKGROUND: In Mediterranean countries, olive tree pruning provides a widely available renewable agricultural residue with, currently, no industrial application. This residue could provide feedstock for the bioethanol industry. In the present study, olive tree pruning biomass pretreated with both ‘liquid hot water’ and ‘dilute‐sulfuric acid’ was tested as a substrate for ethanol production. Three different process configurations, separate hydrolysis and fermentation (SHF), simultaneous saccharification, fermentation and prehydrolysis (PSSF), and simultaneous saccharification and fermentation (SSF), were compared at different water‐insoluble solids concentrations.RESULTS: High ethanol concentration of about 3.7% (v/v) was obtained by separate hydrolysis and fermentation or prehydrolysis and simultaneous saccharification and fermentation of liquid hot water pretreated at 23% (w/w) substrate loading.CONCLUSION: The nature of the pretreated residue allows high substrate concentration (≥17% w/w) to be used in the enzymatic hydrolysis step. Substrate loading of 17% DM has been shown to provide a compromise between hydrolysis efficiency and glucose concentrations for the same enzyme/substrate ratio. Prehydrolysis prior to simultaneous saccharification and fermentation facilitated SSF performance at high substrate loading on liquid hot water pretreated olive pruning residue. This effect was not observed with dilute‐acid pretreated substrate. Copyright © 2011 Society of Chemical Industry
Photo‐reduction and adsorption in aqueous Cr(VI) solution by titanium dioxide, carbon nanotubes and their composite
Authors: Tsai Yung‐Pin , Doong Ruey‐an , Yang Jhih‐Ci , Wu Ying‐Jie 
Published: March 2011

AbstractBACKGROUND: This study compared the removal of aqueous Cr(VI) by multi‐walled carbon nanotubes (CNTs) modified by sulfuric acid, titanium dioxide (TiO2) and composite of CNTs and TiO2.RESULTS: More than 360 h contact time was needed to completely adsorb 3 mg L−1 of Cr(VI) by CNTs, indicating that the rate of adsorption by CNTs alone was slow. The reaction time approaching equilibrium depended on the Cr(VI) concentration. XPS analysis of CNTs after adsorbing Cr(VI) showed that the Cr(VI) on the surface of CNTs was partially reduced to Cr(III). A 3 mg L−1 solution of Cr(VI) was fully photocatalyzed by commercial TiO2 (Degussa P25) in less than 0.5 h under UV irradiation. Unlike P25, reduction by another commercial TiO2 (Hombikat UV100) took 4 h and more than 2 h were necessary for reduction by the composite. Thus the efficiency of Cr(VI) photo‐reduction by the composite was lower than by TiO2, but higher than that by CNTs. XPS analysis of TiO2 and composite showed the existence of both Cr(VI) and Cr(III) on their surfaces.CONCLUSION: In contrast to TiO2, the reduction rate of aqueous Cr(VI) using CNTs as adsorbent was slow. P25 had a markedly higher photocatalytic efficiency than the composite or UV100 alone. Using P25 to reduce aqueous Cr(VI) has a higher potential for practical application. The diameters of TiO2 and CNTs and the ratio of TiO2/CNTs are key problems in the preparation of TiO2/CNTs composite. Copyright © 2011 Society of Chemical Industry
PAA‐Derived Gold Nanorods for Cellular Targeting and Photothermal Therapy
Authors: Kirui Dickson K. , Krishnan Sushmitha , Strickland Aaron D. , Batt Carl A. 
Published: March 2011

AbstractA single‐step LbL procedure to functionalize CTAB‐capped GNRs via electrostatic self‐assembly is reported. This approach allows for consistent biomolecule/GNR coupling using standard carboxyl‐amine conjugation chemistry. The focus is on cancer‐targeting biomolecule/GNR conjugates and selective photothermal destruction of cancer cells by GNR‐mediated hyperthermia and NIR light. GNRs were conjugated to a single‐chain antibody selective for colorectal carcinoma cells and used as probes to demonstrate photothermal therapy. Selective targeting and GNR uptake in antigen‐expressing SW 1222 cells were observed using fluorescence microscopy. Selective photothermal therapy is demonstrated using SW 1222 cells, where >62% cell death was observed after cells are treated with targeted A33scFv‐GNRs. magnified image
The Witten complex for singular spaces of dimension two with cone‐like singularities
Authors: Ludwig Ursula 
Published: March 2011

AbstractThe Witten deformation is a method proposed by Witten which, given a function \documentclass{article}\usepackage{amssymb}\pagestyle{empty}\begin{document}$f:M \longrightarrow \mathbb {R}$\end{document} on a smooth compact manifold M, allows to prove the Morse inequalities. Witten’s proof of the Morse inequalities is analytical and can thus be applied to situations where the Thom‐Smale method is not accessible. In these notes we generalise the Witten deformation to certain singular Riemannian manifolds X which are metric models for singular algebraic curves, and functions on X which we call admissible Morse functions. They are particular examples of stratified Morse functions in the sense of the theory developed by Goresky and MacPherson. © 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim
Reduction of Graphene Oxide by Aniline with Its Concomitant Oxidative Polymerization
Authors: Xu Li Qun , Liu Yi Liang , Neoh Koon‐Gee , Kang En‐Tang , Fu Guo Dong 
Published: March 2011

AbstractGraphene oxide (GO) nanosheets are readily reduced by aniline above room temperature in an aqueous acid medium, with the aniline simultaneously undergoing oxidative polymerization to produce the reduced graphene oxide‐polyaniline nanofiber (RGO‐PANi) composites. The resulting RGO‐PANi composites and RGO (after dissolution of PANi) were characterized by XPS, XRD analysis, TGA, UV–visible absorption spectroscopy, and TEM. It was also found that the RGO‐PANi composites exhibit good specific capacitance during galvanostatic charging–discharging when used as capacitor electrodes. magnified image
Withaferin a suppresses estrogen receptor‐α expression in human breast cancer cells
Authors: Hahm Eun‐Ryeong , Lee Joomin , Huang Yi , Singh Shivendra V. 
Published: March 2011

AbstractWe have shown previously that withaferin A (WA), a promising anticancer constituent of Ayurvedic medicine plant Withania somnifera, inhibits growth of MCF‐7 and MDA‐MB‐231 human breast cancer cells in culture and MDA‐MB‐231 xenografts in vivo by causing apoptosis. However, the mechanism of WA‐induced apoptosis is not fully understood. The present study was designed to systematically determine the role of tumor suppressor p53 and estrogen receptor‐α (ER‐α) in proapoptotic response to WA using MCF‐7, T47D, and ER‐α overexpressing MDA‐MB‐231 cells as a model. WA treatment resulted in induction as well as increased S15 phosphorylation of p53 in MCF‐7 cells, but RNA interference of this tumor suppressor conferred modest protection at best against WA‐induced apoptosis. WA‐mediated growth inhibition and apoptosis induction in MCF‐7 cells were significantly attenuated in the presence of 17β‐estradiol (E2). Exposure of MCF‐7 cells to WA resulted in a marked decrease in protein levels of ER‐α (but not ER‐β) and ER‐α regulated gene product pS2, and this effect was markedly attenuated in the presence of E2. WA‐mediated down‐regulation of ER‐α protein expression correlated with a decrease in its nuclear level, suppression of its mRNA level, and inhibition of E2‐dependent activation of ERE2e1b‐luciferase reporter gene. Ectopic expression of ER‐α in the MDA‐MB‐231 cell line conferred partial but statistically significant protection against WA‐mediated apoptosis, but not G2/M phase cell cycle arrest. Collectively, these results indicate that WA functions as an anti‐estrogen, and the proapoptotic effect of this promising natural product is partially attenuated by p53 knockdown and E2‐ER‐α. © 2011 Wiley‐Liss, Inc.
Methyl‐CpG binding column‐based identification of nine genes hypermethylated in colorectal cancer
Authors: Kober Paulina , Bujko Mateusz , Olędzki Janusz , Tysarowski Andrzej , Siedlecki Janusz A. 
Published: March 2011

AbstractDNA methylation is an epigenetic event that plays a role in gene expression regulation. Alterations in DNA methylation contribute to cancer development and progression. The aim of this study was to identify gene promoters aberrantly methylated in colorectal tumor tissue in comparison to normal colonic mucosa. Analyses were performed on two pooled DNA samples: from normal and cancerous tissue obtained from CRC patients. DNA was fractionated according to methylation degree with the use of affinity column containing methyl‐CpG binding domain. To identify novel hypermethylated gene promoters, methylated DNA from normal and from cancerous tissues were analyzed with the use of promoter microarrays. We identified nine novel genes hypermethylated in colorectal cancer. The frequency of their promoter methylation was assessed in the larger group of patients (n = 77): KCNK12 (methylated in 41% of CRC patients), GPR101 (40%), CDH2 (45%), BARX1 (56%), CNTFR (22%), SYT6 (64%), SMO (21%), EPHA5 (43%), and GSPT2 (21%). The results of gene expression level analysis suggest the role of promoter methylation in downregulation of six out of nine genes examined. We did not find correlation between gene methylation and age, gender, tumor grade or stage. Importantly, in stage IV CRC methylation of GPR101 correlated with longer time to progression (P = 0.0042; HR = 2.5468; 95% CI 1.5391–10.0708). © 2011 Wiley Periodicals, Inc.
Genetic polymorphism in the 3′‐untranslated region of the E‐cadherin gene is associated with risk of different cancers
Authors: Li Yan , Tang Yuanjia , Zhou Rongmiao , Sun Donglan , Duan Yanan , Wang Na , Chen Zhifeng , Shen Nan 
Published: March 2011

AbstractThe genetic polymorphisms in E‐cadherin gene (CDH1) may affect invasive/metastatic disease development by altering gene transcriptional activity. In this paper, we investigated the effect of 3′‐UTR +54C/T polymorphism (rs1801026) in CDH1 gene on the risk and progression of several common cancers. Multiple completely independent case‐control analyses of 1081 cancer patients with esophageal squamous cell carcinoma (ESCC), gastric cardiac adenocarcinoma (GCA), non‐small‐cell lung cancer (NSCLC), and cervical cancer and 1131 control subjects in northern Chinese populations. The results showed that the carriers with T allele were significantly decreased the risk of developing GCA, NSCLC, and cervical cancer, with an adjusted odds ratio of 0.67 (95% CI = 0.48–0.91), 0.68 (95% CI = 0.49–0.92), and 0.66 (95% CI = 0.48–0.92), respectively. There were no association between the frequency of genotype and the clinicopathological features of ESCC, GCA, and NSCLC, but the frequency of T allele was significantly lower in patients of stage III cervical cancer (P = 0.026). These results suggested that the 3′‐UTR +54C/T polymorphism in CDH1 may be a marker for genetic susceptibility of cancer. © 2011 Wiley Periodicals, Inc.