bluuebunny/crossref_metadata_2025_split huggingface dataset:
Long‐term data collection at USDA experimental sites for studies of ecohydrology
Authors: Moran M. Susan , Peters Debra P. C. , McClaran Mitchel P. , Nichols Mary H. , Adams Mary B. 
Published: November 2008

AbstractThe science of ecohydrology is characterized by feedbacks, gradual trends and extreme events that are best revealed with long‐term experimental studies of hydrological processes and biological communities. In this review, we identified 81 US Department of Agriculture (USDA) experimental watersheds, forests and ranges with data records of more than 20 years measuring important ecosystem dynamics such as variations in vegetation, precipitation, climate, runoff, water quality and soil moisture. Through a series of examples, we showed how USDA long‐term data have been used to understand key ecohydrological issues, including (1) time lag between cause and effects, (2) critical thresholds and cyclic trends, (3) context of rare and extreme events and (4) mechanistic feedbacks for simulation modelling. New analyses of network‐wide, long‐term data from USDA experimental sites were used to illustrate the potential for multi‐year, multi‐site ecohydrological research. Three areas of investigation were identified to best exploit the unique spatial distribution and long‐term data of USDA experimental sites: convergence, cumulative synthesis and autocorrelation. This review underscored the need for continuous, interdisciplinary data records spanning more than 20 years across a wide range of ecosystems within and outside the conterminous USA to address major crosscutting problems facing ecohydrology. Conversely, the heightened interest in ecohydrology has impacted USDA experimental sites by encouraging new long‐term data collection efforts and adapting existing long‐term data collection networks to address new science issues. Copyright © 2008 John Wiley & Sons, Ltd.
Sphagnum under pressure: towards an ecohydrological approach to examining Sphagnum productivity
Authors: Thompson D. K. , Waddington J. M. 
Published: November 2008

AbstractThe genus Sphagnum is the key peat‐forming bryophyte in boreal ecosystems. Relying entirely on passive capillary action for water transport, soil moisture is often the limiting factor in Sphagnum production, and hence peat accumulation. While several hydrological models of peat physics and peatland water movement exist, these models do not readily interface with observations and models of peatland carbon accumulation. A conflict of approaches exists, where hydrological studies primarily utilize variables such as hydraulic head, while ecological models of Sphagnum growth adopt the coarse hydrological variables of water table (WT), volumetric water content (VWC) or gravimetric water content (WC). This review examines the potential of soil pressure head as a measurement to link the hydrological and ecological functioning of Sphagnum in peatlands. The non‐vascular structure of Sphagnum mosses and the reliance on external capillary transport of water in the mosses make them an ideal candidate for this approach. The main advantage of pressure head is the ability to mechanistically link plot‐scale hydrology to cellular‐scale water requirements and carbon exchange. Measurement of pressure head may improve photosynthetic process representation in the next generation of peatland models. Copyright © 2008 John Wiley & Sons, Ltd.
Comparative metabolite profiling of carboxylic acids in rat urine by CE‐ESI MS/MS through positively pre‐charged and 2H‐coded derivatization
Authors: Yang Wen‐Chu , Regnier Fred E. , Adamec Jiri 
Published: November 2008

AbstractA new approach to the selective comparative metabolite profiling of carboxylic acids in rat urine was established using CE‐MS and a method for positively pre‐charged and 2H‐coded derivatization. Novel derivatizing reagents, N‐alkyl‐4‐aminomethyl‐pyridinum iodide (alkyl=butyl, butyl‐d9 or hexyl), containing quaternary amine and stable‐isotope atoms (deuterium), were introduced for the derivatization of carboxylic acids. CE separation in positive polarity showed high reproducibility (0.99–1.32% RSD of migration time) and eliminated problems with capillary coating known in CE‐MS anion analyses. Essentially complete ionization and increased hydrophobicity after the derivatization also enhanced MS detection sensitivity (e.g. formic acid was detected at 0.5 pg). Simultaneous derivatization of one sample using two structurally similar reagents, N‐butyl‐4‐aminomethyl‐pyridinum iodide (BAMP) and N‐hexyl‐4‐aminomethyl‐pyridinum iodide, provided additional information for recognizing a carboxylic acid in an unknown sample. Moreover, characteristic fragmentation acquired by online CE‐MS/MS allowed for identification and categorization of carboxylic acids. Applying this method on rat urine, we found 59 ions matching the characteristic patterns of carboxylic acids. From these 59, 32 ions were positively identified and confirmed with standards. For comparative analysis, 24 standard carboxylic acids were derivatized by chemically identical but isotopically distinct BAMP and N‐butyl‐d9‐4‐aminomethyl‐pyridinium iodide, and their derivatization limits and linearity ranges were determined. Comparative analysis was also performed on two individual urine samples derivatized with BAMP and N‐butyl‐d9‐4‐aminomethyl‐pyridinium iodide. The metabolite profiling variation between these two samples was clearly visualized.
Identification of inorganic ions in post‐blast explosive residues using portable CE instrumentation and capacitively coupled contactless conductivity detection
Authors: Hutchinson Joseph P. , Johns Cameron , Breadmore Michael C. , Hilder Emily F. , Guijt Rosanne M. , Lennard Chris , Dicinoski Greg , Haddad Paul R. 
Published: November 2008

AbstractNovel CE methods have been developed on portable instrumentation adapted to accommodate a capacitively coupled contactless conductivity detector for the separation and sensitive detection of inorganic anions and cations in post‐blast explosive residues from homemade inorganic explosive devices. The methods presented combine sensitivity and speed of analysis for the wide range of inorganic ions used in this study. Separate methods were employed for the separation of anions and cations. The anion separation method utilised a low conductivity 70 mM Tris/70 mM CHES aqueous electrolyte (pH 8.6) with a 90 cm capillary coated with hexadimethrine bromide to reverse the EOF. Fifteen anions could be baseline separated in 7 min with detection limits in the range 27–240 μg/L. A selection of ten anions deemed most important in this application could be separated in 45 s on a shorter capillary (30.6 cm) using the same electrolyte. The cation separation method was performed on a 73 cm length of fused‐silica capillary using an electrolyte system composed of 10 mM histidine and 50 mM acetic acid, at pH 4.2. The addition of the complexants, 1 mM hydroxyisobutyric acid and 0.7 mM 18‐crown‐6 ether, enhanced selectivity and allowed the separation of eleven inorganic cations in under 7 min with detection limits in the range 31–240 μg/L. The developed methods were successfully field tested on post‐blast residues obtained from the controlled detonation of homemade explosive devices. Results were verified using ion chromatographic analyses of the same samples.
CE with on‐line detection by ICP‐MS for studying the competitive binding of zinc against cadmium for glutathione
Authors: Li Yan , Liu Jing‐Min , Xia Yun‐Long , Jiang Yan , Yan Xiu‐Ping 
Published: November 2008

AbstractDevelopment of a feasible method for studying the competitive interaction between a pair of antagonists is essential for understanding the antagonism of trace metals in biological systems. Herein, we report the application of CE on‐line coupled with ICP mass spectroscopy (CE‐ICP‐MS) to investigate the competitive binding of Zn2+ against Cd2+ for glutathione (GSH), which is related to the detoxification of Cd2+ in biological system, and introduce a method to evaluate the kinetics and thermodynamics for the competitive binding of Zn2+ against Cd2+ for GSH. The CE‐ICP‐MS hybrid technique allows easy and sensitive probing of the competitive binding of Zn2+ against Cd2+ for GSH and quantitative determination of the important thermodynamic and kinetic parameters of the competitive binding of Zn2+ against Cd2+ for GSH. Owing to the high sensitivity and element selectivity with multi‐elements detection capacity of ICP‐MS, we detailed the evaluation of the kinetics and thermodynamics describing the competition of Zn2+ against Cd2+ for GSH from the systematic data obtained by CE‐ICP‐MS. The competitive binding of Zn2+ against Cd2+ for GSH was demonstrated exothermic and thermodynamically favorable (ΔG=−7.2 kJ/mol) and driven entirely by a large favorable enthalpy decrease (ΔH=−15.1 kJ/mol) but with an unfavorable entropy decrease (ΔS=−25.6 J/mol/K). The kinetic data were fit to a second‐order equation with the reaction rate constant (k) of (2.18±0.10)×102 L/(mol·s) under the simulated physiological condition.
Chemometric resolution of fully overlapped CE peaks: Quantitation of carbamazepine in human serum in the presence of several interferences
Authors: Vera‐Candioti Luciana , Culzoni María J. , Olivieri Alejandro C. , Goicoechea Héctor C. 
Published: November 2008

AbstractDrug monitoring in serum samples was performed using second‐order data generated by CE‐DAD, processed with a suitable chemometric strategy. Carbamazepine could be accurately quantitated in the presence of its main metabolite (carbamazepine epoxide), other therapeutic drugs (lamotrigine, phenobarbital, phenytoin, phenylephrine, ibuprofen, acetaminophen, theophylline, caffeine, acetyl salicylic acid), and additional serum endogenous components. The analytical strategy consisted of the following steps: (i) serum sample clean‐up to remove matrix interferences, (ii) data pre‐processing, in order to reduce the background and to correct for electrophoretic time shifts, and (iii) resolution of fully overlapped CE peaks (corresponding to carbamazepine, its metabolite, lamotrigine and unexpected serum components) by the well‐known multivariate curve resolution‐alternating least squares algorithm, which extracts quantitative information that can be uniquely ascribed to the analyte of interest. The analyte concentration in serum samples ranged from 2.00 to 8.00 mg/L. Mean recoveries were 102.6% (s=7.7) for binary samples, and 94.8% (s=13.5) for spiked serum samples, while CV (%)=4.0 was computed for five replicate, indicative of the acceptable accuracy and precision of the proposed method.
Opposing mixed convection and its interaction with radiation inside eccentric horizontal cylindrical annulus
Authors: Sarkar Anjan , Mahapatra S. K. , Sarkar A. 
Published: November 2008

AbstractIn the present investigation, the coupled phenomenon of opposing mixed convection and radiation within differentially heated eccentric horizontal cylindrical annulus has been numerically simulated. The radiation transfer contributed from the participating medium is obtained by solving the nonlinear integro‐differential radiative transfer equation using discrete ordinate method. The participating gray medium is considered to be emitting, absorbing and isotropically scattering. The walls of the annulus are considered to be opaque, diffuse and gray. In the study it has been observed that the Richardson number ‘Ri’ has a small effect on the total Nusselt number ‘Nu’ in mixed convection heat transfer with or without radiation. From the present investigation it is found that substantial changes occur in isotherms as well as in flow patterns, when the Richardson number is allowed to vary in the range of 0.01–1. The influence of radiative parameters on the interaction phenomenon has been delineated through isotherm and streamline pattern. Copyright © 2008 John Wiley & Sons, Ltd.
A Benzofuranoid and Two Clerodane Diterpenoids from Pulicaria wightiana
Authors: Venkateswarlu Katta , Satyalakshmi Gandham , Suneel Kanaparthy , Reddy Thummala Sreenivasulu , Raju Tuniki Venugopal , Das Biswanath 
Published: November 2008

AbstractMethyl 5‐formyl‐1‐benzofuran‐6‐carboxylate (1) and the two clerodane diterpenes, methyl 6‐oxocleroda‐3,13‐dien‐15,16‐olid‐18‐oate (2) and 2β‐(2‐methylbutanoyl)cleroda‐3,13‐dien‐15,16‐olid‐18‐oic acid (3), together with 15 known compounds, were isolated from the aerial parts of Pulicaria wightiana. The structures of the new compounds 1, 2, and 3 were established by spectroscopic (mainly 1D‐ and 2D‐NMR) methods.
Synthesis and Characterization of New Binaphthyl‐Linked Phenanthroline‐, Bipyridine‐, or Pyridine‐Derived Ligands, and the Study of Their Cytotoxic Activity
Authors: Beynek Nesrin , Uluçam Gühergül , Benkli Kadriye , Koparal Ays̨e Tansu 
Published: November 2008

AbstractIn the present work, we describe the synthesis and characterization of five new versatile acyclic or macrocyclic ligands containing binaphthyl‐linked pyridine, bipyridine, or phenanthroline groups in their framework (see Schemes 1–4). The structures of the ligands were elucidated on the basis of elemental analyses, IR, 1H‐NMR, 13C‐NMR, and FAB mass spectra. The cytotoxicity of these compounds was tested in vitro by using the tetrazolium salt reduction (MTT) assay on A549 (human lung carcinoma epithelial like) cells. All of the tested compounds induced time‐ and concentration‐dependent cytotoxic effect.
Chemical Constituents from Myrsine africana L.
Authors: Zou Yan‐Ping , Tan Chang‐Heng , Wang Bao‐De , Zhu Da‐Yuan , Kim Se‐Kwon 
Published: November 2008

AbstractThree new compounds, myrsinoside A (=2,4‐dihydroxy‐6‐methylphenyl β‐D‐(6′‐galloyl)glucopyranoside; 1), myrsinoside B (2,4‐dihydroxy‐6‐methylphenyl β‐D‐glucopyranoside; 2), and (3β,16α,20α)‐3,16,28‐trihydroxyolean‐12‐en‐29‐oic acid 3‐{O‐β‐D‐glucopyranosyl‐(1→2)‐O‐[β‐D‐glucopyranosyl‐(1→4)]‐α‐L‐arabinopyranoside} (3), along with four known compounds, were isolated from the stems of Myrsine africana L. The structures of these new compounds were elucidated on the basis of spectroscopic analysis, including 1D‐ and 2D‐NMR and ESI‐MS techniques, and chemical methods.
Rapidly increasing incidence of papillary serous carcinoma of the peritoneum in the United States: Fact or artifact?
Authors: Goodman Marc T. , Shvetsov Yurii B. 
Published: November 2008

AbstractPapillary serous carcinoma of the peritoneum (PSCP) has been recognized for almost 5 decades, but little is known about the etiology or pathogenesis of this uncommon malignancy. The objective of this analysis was to examine trends in the incidence of PSCP in the United States. Invasive PSCP cases (N = 4,389) were identified through 24 population‐based registries in the United States during the period 1995‐2004. Incidence rates were calculated per million population. PSCP is a disease of older women, with few cases diagnosed before the age of 40 years. The incidence of PSCP was 64% lower among black women and 47% lower among Asian‐Pacific Islander women compared with white women. Rates among Hispanic women were 39% lower than among non‐Hispanic women. The majority of PSCP (68%) was diagnosed at a distant stage, underscoring the difficulty of diagnosing this malignancy. The incidence of PSCP has increased dramatically during the past decade in the United States with the greatest rise (>13% per year) among non‐Hispanic and white women. This trend was more pronounced among older women and women with early stage disease. The incidence of PSCP shows substantial racial and ethnic diversity. The increase in the rate of PSCP among all racial and ethnic groups during the 10‐year observation period is cause for some alarm. Although the reason for this temporal trend is unknown, some of the increase may be attributable to reclassification of ovarian carcinoma to the peritoneum. © 2008 Wiley‐Liss, Inc.
Molecular mechanisms involved in activity of h7C10, a humanized monoclonal antibody, to IGF‐1 receptor
Authors: Broussas Matthieu , Dupont Joëlle , Gonzalez Alexandra , Blaecke Aline , Fournier Mathilde , Corvaïa Nathalie , Goetsch Liliane 
Published: November 2008

AbstractIGF‐1 receptor (IGF‐1R) plays a key role in the development of numerous tumors. Blockade of IGF‐1R axis using monoclonal antibodies constitutes an interesting approach to inhibit tumor growth. We have previously shown that h7C10, a humanized anti–IGF‐1R Mab, exhibited potent antitumor activity in vivo. However, mechanisms of action of h7C10 are still unknown. Here, we showed that h7C10 inhibited IGF‐1–induced IGF‐1R phosphorylation in a dose‐dependent manner. Also, h7C10 abolished IGF‐1–induced activation of PI3K/AKT and MAPK pathways. Cell cycle progression and colony formation were affected in the presence of h7C10 probably because of the inhibition of IGF‐1–induced cyclin D1 and E expression. In addition, we demonstrated that h7C10 induced a rapid IGF‐1R internalization leading to an accumulation into cytoplasm resulting in receptor degradation. Using lysosome and proteasome inhibitors, we observed that the IGF‐1R α‐ and β‐chains could follow different degradation routes. Thus, we demonstrated that antitumoral properties of h7C10 are the result of IGF‐1–induced cell signaling inhibition and down‐regulation of IGF‐1R level suggesting that h7C10 could be a candidate for therapeutic applications. © 2008 Wiley‐Liss, Inc.
Compact spheroid formation by ovarian cancer cells is associated with contractile behavior and an invasive phenotype
Authors: Sodek Katharine L. , Ringuette Maurice J. , Brown Theodore J. 
Published: November 2008

AbstractOvarian cancer cells are present in malignant ascites both as individual cells and as multicellular spheroid aggregates. Although spheroid formation affords protection of cancer cells against some chemotherapeutic agents, it has not been established whether a relationship exists between invasive behavior and predisposition to spheroid formation. Aspects of spheroid formation, including cell‐matrix adhesion, remodeling and contractility are characteristic myofibroblast‐like behaviors associated with fibrosis that contribute to tumor growth and dissemination. We explored the possibility that cell behaviors that promote spheroid formation also facilitate invasion. Our analysis of 6 human ovarian cancer cell lines indicated that ovarian cancer cells possessing myofibroblast‐like properties formed compact spheroids and invaded 3D matrices. These cells readily contracted collagen I gels, possessed a spindle‐like morphology, and had elevated expression of genes associated with the TGFβ‐mediated fibrotic response and/or β1 integrin function, including fibronectin (FN), connective tissue growth factor (CTGF/CCN2), lysyl oxidase (LOX1), tissue transglutaminase 2 (TGM2) and urinary plasminogen activator receptor (uPAR). Whereas cell aggregation was induced by TGFβ, and by β1‐integrin overexpression and activation, these treatments did not stimulate the contractile activity required for spheroid compaction. The positive relationship found between compact spheroid formation and invasive behavior implies a preferential survival of an invasive subpopulation of ovarian cancer cells, as cells in spheroids are more resistant to several chemotherapeutics. Preventing the formation of ovarian cancer spheroids may represent a novel strategy to improve the efficacy of existing therapeutics. © 2008 Wiley‐Liss, Inc.
Climate prediction for Brazil's Nordeste by empirical and numerical modeling methods
Authors: Hastenrath Stefan , Sun Liqiang , Moura Antonio Divino 
Published: November 2008

AbstractClimate prediction for Brazil's Nordeste meaningfully uses information through January to forecast the rainfall of March–June. Empirical methods developed at the University of Wisconsin use as predictors preseason (October–January) rainfall in the region and January indices of the fields of meridional wind component and sea surface temperature (SST) in the tropical Atlantic and the equatorial Pacific, as input to stepwise multiple regression to predict the March–June rainfall at a network of 27 stations. The training period is 1921–1957, the verification period 1958–1989, and real‐time forecasting continued to 2000. A numerical model (ECHAM4.5) experiment conducted at International Research Institute for Climate and Society at Columbia University used global SST information through January to predict the March–June rainfall at three gridpoints in the Nordeste for the years 1968–1999. For the same predictand, a complementary empirical experiment was conducted using the gridded rainfall observations, again with training period 1921–1957, to yield predictions for 1968–1999. Over this period predicted versus observed rainfall are evaluated in terms of correlation, root‐mean‐square error, absolute error, and bias. Compared with the empirical method the numerical modelling produces larger errors and negative bias. The empirical method captures 59% and the numerical modelling 49% of the variance. Copyright © 2008 Royal Meteorological Society
Rapid determination of bisphenol A in drinking water using dispersive liquid‐phase microextraction with in situ derivatization prior to GC‐MS
Authors: Wang Xia , Diao Chun‐Peng , Zhao Ru‐Song 
Published: November 2008

AbstractThis paper described a novel approach for the determination of bisphenol A by dispersive liquid‐phase microextraction with in situ acetylation prior to GC‐MS. In this derivatization/extraction method, 500 μL acetone (disperser solvent) containing 30.0 μL chlorobenzene (extraction solvent) and 30.0 μL acetic anhydride (derivatization reagent) was rapidly injected into 5.00 mL aqueous sample containing bisphenol A and K2CO3 (0.5% w/v). Within a few seconds the analyte was derivatized and extracted at the same time. After centrifugation, 1.0 μL of sedimented phase containing enriched analyte was determined by GC‐MS. Some important parameters, such as type and volume of extraction and disperser solvent, volume of acetic anhydride, derivatization and extraction time, amount of K2CO3, and salt addition were studied and optimized. Under the optimum conditions, the LOD and the LOQ were 0.01, 0.1 μg/L, respectively. The experimental results indicated that there was linearity over the range 0.1–50 μg/L with coefficient of correlation 0.9997, and good reproducibility with RSD 3.8% (n = 5). The proposed method has been applied for the analysis of drinking water samples, and satisfactory results were achieved.
HPLC‐ESI‐MS analysis of oral human fluids reveals that gingival crevicular fluid is the main source of oral thymosins β4 and β10
Authors: Inzitari Rosanna , Cabras Tiziana , Pisano Elisabetta , Fanali Chiara , Manconi Barbara , Scarano Emanuele , Fiorita Antonella , Paludetti Gaetano , Manni Armando , Nemolato Sonia , Faa Gavino , Castagnola Massimo , Messana Irene 
Published: November 2008

AbstractThymosin β4 (Tβ4), its sulfoxide, and thymosin β10 (Tβ10) were detected in human saliva and identified by different strategies based on RP HPLC coupled to electrospray multidimensional IT MS. Tβ4 was almost always detected in whole saliva, its sulfoxide sporadically, Tβ10 rarely. Tβ4 was undetectable in parotid saliva and less concentrated in submandibular/sublingual saliva than in whole saliva. Analysis of gingival crevicular fluid revealed high relative amounts of Tβ4, Tβ4 sulfoxide, and Tβ10 in all the samples. Tβ4 mean concentration was 200 times higher in crevicular fluid (20 μmol/L, N = 9) than in whole saliva (0.1 μmol/L, N = 9). Crevicular fluid concentration of Tβ4 (ca. 5% represented by its sulfoxide) and β10 significantly correlated (r = 0.856; N = 9), and their ratio was about 5. A significant correlation was also observed between Tβ4 concentrations in whole saliva and gingival crevicular fluid (r = 0.738; N = 9). Immunohistochemical analysis of the major salivary glands showed that immunoreactivity for Tβ4 is restricted to ductal cells, with minor degree of focal positivity in some acinar cells. On the whole, results indicate that gingival sulcus is a main, although not the sole, source for oral Tβ4 and Tβ10.