bluuebunny/crossref_metadata_2025_split huggingface dataset:
Isotopic time‐series partitioning of streamflow components in wetland‐dominated catchments, lower Liard River basin, Northwest Territories, Canada
Authors: St Amour Natalie A. , Gibson John J. , Edwards Thomas W. D. , Prowse Terry D. , Pietroniro Alain 
Published: October 2005

AbstractThe distribution of stable water isotopes provides valuable insight into runoff generation processes in subarctic wetland regions of the Mackenzie River basin, a major freshwater contributor to the Arctic Ocean and the focus of intensive hydrological research as part of Canada's contribution to the Global Energy and Water Cycle Experiment (GEWEX). This article describes a streamflow hydrograph separation analysis carried out over three complete annual cycles (1997–1999) for five subarctic catchments ranging in size from 202 to 2050 km2 situated near the confluence of the Liard and Mackenzie rivers. This heterogeneous landscape, characterized by extensive wetlands (fen and bog), shallow lakes and widespread discontinuous permafrost, is representative of vast flow‐contributing areas of the upper Mackenzie Valley, and is suspected to be highly sensitive to climate variability and change. We document seasonal patterns and interannual variability in the isotopic composition of local streamflow, attributable to mixing of three distinctly labelled flow sources, namely groundwater, surface water plus rain, and direct snowmelt, and apply these isotopic signals to partition sources and their temporal variability. Although groundwater input is the dominant and most persistent streamflow source in all five catchments throughout the year, direct snowmelt runoff via surface and shallow subsurface pathways (during spring freshet) and surface waters from lakes and wetlands situated in low‐lying areas of the basins (during summer and fall) are also significant seasonal contributors. Catchment‐specific differences are also apparent, particularly in the generation of snowmelt runoff, which is more attenuated in fen‐dominated than in bog‐dominated catchments. The data set additionally reveals notable interannual variability in snow isotope signatures and snow water equivalent, apparently enhanced by the 1998 El Niño event. Copyright © 2005 John Wiley & Sons, Ltd.
High school completion and future youth unemployment: new evidence from High School and Beyond
Authors: Li Mingliang 
Published: October 2005

AbstractIn this paper, I provide new evidence from High School and Beyond (HSB) on the effects of compulsory attendance on high school completion and future youth unemployment. I develop Bayesian estimation approaches to the simultaneous equation model with ordered probit and two‐limit censored regression and the bivariate duration model, accounting for the heterogeneity in returns to education and the nonlinearity in the effects of compulsory attendance. I find substantial variability in returns to education across schools and evidence of diminishing marginal effects of compulsory attendance on high school completion. The simulation results suggest that increasing the compulsory attendance age raises the probability of completing high school and reduces the proportion of time the individuals are unemployed. These effects are much more pronounced for disadvantaged students but less pronounced for advantaged students, suggesting the potential effects of compulsory attendance on reducing the inequality in education and employment. Copyright © 2005 John Wiley & Sons, Ltd.
What role do surfaces play in GB models? A new‐generation of surface‐generalized born model based on a novel gaussian surface for biomolecules
Authors: Yu Zhiyun , Jacobson Matthew P. , Friesner Richard A. 
Published: October 2005

AbstractWe have developed a version of our surface generalized Born (SGB) model that employs a Gaussian surface, as opposed to the van der Waals surface used previously. The Gaussian surface is smooth and its properties are analytically differentiable with respect to the positions of atoms. A significant advantage of a solvent model based on this analytically differentiable surface is the availability of analytical gradients of the surface and solvation forces. An efficient and robust algorithm is designed to construct and triangulate the Gaussian surface for large biomolecules with arbitrary shapes, and to compute the various terms required for energy gradients. The Gaussian surface is shown to better mimic the boundary between the solute and solvent by properly addressing solvent accessibility, as is demonstrated by comparisons with standard Poisson–Boltzmann calculations for proteins of different sizes. These results also demonstrate that surface definition is a dominant contribution to differences between GB and PB calculations, especially if the system is large. Application of the new surface to prediction of long loop regions is presented, and significant improvement in the energetics is seen compared with results obtained using the van der Waals surface, even in the absence of optimized empirical correction terms that were used in the latter calculations. © 2005 Wiley Periodicals, Inc. J Comput Chem 27: 72–89, 2006
Molecular structure study of dimethoxyphenyl‐substituted phosphonodipeptides by infrared, Raman, and surface enhanced Raman spectroscopies
Authors: Podstawka Edyta , Kozłowski Henryk , Proniewicz Leonard M. 
Published: October 2005

AbstractIn this study, Fourier‐transform Raman (FT‐RS) and infrared (FT‐IR) absorption spectroscopies were employed to characterize the molecular structures ofL‐Ala‐(3,4‐dimethoxy)‐L‐Phe‐PO3H2(A) andL‐Ala‐(3,4‐dimethoxy)‐(des‐CH2)‐L‐Phe‐PO3H2(B) phosphonodipeptides, whereL‐Phe denotesL‐phenylalanine andL‐Ala,L‐alanine. The vibrational band assignments have been proposed. In order to determine the structures of these dimethoxyphenyl‐substituted phosphonodipeptides adsorbed on a colloidal silver surface, surface enhanced Raman spectra (SERS) were measured. The analysis of SERS band intensities showed that these dimethoxyphenyl‐substituted phosphonodipeptides directly interacted with the silver surface through the aromatic ring of Phe that adopted an orientation almost perpendicular to the silver surface. We also showed that intense enhancement of the νas(NH2), δas(PO32−), and ν(PO) modes ofL‐Ala‐(3,4‐dimethoxy)‐L‐Phe‐PO3H2suggested that these groups were mainly involved in the interaction with the silver colloid. Additionally, we proved that in the SERS spectrum ofL‐Ala‐(3,4‐dimethoxy)‐(des‐CH2)‐L‐Phe‐PO3H2, several vibrations of the CH3group were enhanced, indicating a flattened orientation of the peptide backbone on the silver surface. Copyright © 2005 John Wiley & Sons, Ltd.
Multidimensional Chromatographic and Hyphenated Techniques for Hydrophilic Copolymers, 1
Authors: Adler Martina , Rittig Frank , Becker Stefan , Pasch Harald 
Published: October 2005

AbstractSummary: The chromatographic analysis of hydrophilic copolymers is complicated due to the fact that in most cases aqueous eluents must be used. In aqueous eluents different polar and ionic effects may disturb the selective interactions between the macromolecules and the stationary phase making it impossible to separate such copolymers with regard to chemical composition. Therefore, 2D chromatography combining a separation according to composition with a separation according to molar mass has been applied mostly to polymers that are soluble in organic solvents. The present contribution describes experimental approaches to analyze such hydrophilic copolymers by 2D‐chromatography. For a model polymer system resulting from the copolymerization of methacrylic acid and a poly(ethylene glycol) macromonomer, it is shown that different analytical techniques including SEC, LC‐CC, MALDI‐TOF MS and 2D chromatography can be used to analyze the different parameters of molecular heterogeneity of such copolymers.2D separation of poly(MPEG‐MM 2), 1st dimension: LC‐CC, 2nd dimension: SEC.magnified image2D separation of poly(MPEG‐MM 2), 1st dimension: LC‐CC, 2nd dimension: SEC.
1H and 13C NMR spectral data for a tricyclic derivative of a Diels–Alder adduct
Authors: Pedersoli Susimaire , Constantino Mauricio Gomes , José da Silva Gil Valdo 
Published: October 2005

AbstractA complete NMR analysis with full assignment for 1H and 13C NMR spectral data for 5‐(acetyloxy)‐3‐hydroxy‐9,10‐dimethoxy‐6‐oxo‐11‐oxatricyclo[6.2.1.02,7]undec‐2‐yl acetate (8) is described. This compound was prepared by rapid hydrogenation of the unstable Diels–Alder adduct obtained from the reaction between 3,4‐dimethoxyfuran (4) and 2,5‐diacetoxy‐1,4‐benzoquinone (5). Full homonuclear hydrogen coupling constants measurements and molecular mechanics calculations were performed for the determination of the relative stereochemistry. Copyright © 2005 John Wiley & Sons, Ltd.
29Si NMR in LC–NMR analysis of silicones
Authors: Blechta Vratislav , Sýkora Jan , Hetflejš Jiří , Šabata Stanislav , Schraml Jan 
Published: October 2005

AbstractIt is demonstrated using a practical example that indirect detection of 29Si NMR signals is sufficiently sensitive in LC–NMR stop‐flow arrangement to analyze mixtures of siloxane polymers. New cryogenic probes with better signal‐to‐noise ratio will turn this version of LC–NMR into a routine method for analysis of siloxane polymers. Copyright © 2005 John Wiley & Sons, Ltd.
Assignment of absolute configuration of cyclic secondary amines by NMR techniques using Mosher's method: a general procedure exemplified with (−)‐isoanabasine
Authors: Kang Chuan‐Qing , Guo Hai‐Quan , Qiu Xue‐Peng , Bai Xiao‐Li , Yao Hai‐Bo , Gao Lian‐Xun 
Published: October 2005

AbstractA general procedure to determine the absolute configuration of cyclic secondary amines with Mosher's NMR method is demonstrated, with assignment of absolute configuration of isoanabasine as an example. Each Mosher amide can adopt two stable conformations (named rotamers) caused by hindered rotation around amide CN bond. Via a three‐step structural analysis of four rotamers, the absolute configuration of (−)‐isoanabasine is deduced to be (R) on the basis of Newman projections, which makes it easy to understand and clarify the application of Mosher's method to cyclic secondary amines. Furthermore, it was observed that there was an unexpected ratio of rotamers of Mosher amide derived from (R)‐isoanabasine and (R)‐Mosher acid. This phenomenon implied that it is necessary to distinguish the predominant rotamer from the minor one prior to determining the absolute configuration while using this technique. Copyright © 2005 John Wiley & Sons, Ltd.
Changes in androgen‐producing cell size and circulating 11‐ketotestosterone level during female–male sex change of honeycomb grouper Epinephelus merra
Authors: Alam Mohammad Ashraful , Bhandari Ramji Kumar , Kobayashi Yasuhisa , Nakamura Shigeo , Soyano Kiyoshi , Nakamura Masaru 
Published: October 2005

Abstract11‐ketotestosterone (11‐KT), a potent male‐specific androgen in fish, has important roles on spermatogenesis, male behavior, and nuptial coloration. The site of 11‐KT synthesis and its role on male germ cell development during protogynous sex change is not clearly understood. We examined the dynamics of steroidogenic enzymes immunolocalization, viz cholesterol side‐chain cleavage (P450scc), biomarker of steroids and cytochrome P45011β‐hydroxylase (P45011β), downstream to 11‐KT production, throughout the process of sex change in honeycomb grouper (Epinephelus merra). In female, P450scc immunoreactivity (‐ir) was observed in the theca layer and tunica near blood vessels (BV). During the onset of sex change, P450scc reactive cells were observed in the remaining follicle layer of degenerated oocyte of the ovo‐testis in early transitional (ET) and late transitional (LT). In male, P450scc‐ir was localized in the interstitial Legdig cells of testis. P45011β reactive cells were observed in the tunica near BV in female but not in theca layer. In ET and LT phases gonads, P45011β localized in remaining follicle layer of degenerated oocyte and tunica near BV. On the other hand, in male, both interstices and tunica near BV showed strong signals against P45011β. Moreover, in vivo and in vitro levels of 11‐KT related with the changes in the nuclei diameter of P45011β‐positive cells in both tunica near BV and remaining follicle layer of degenerated oocyte to interstices during the progress of sex change. The present results suggest that 11‐KT produced in the tunica near BV may provide the stimulus for female to degenerate oocytes and initiate sex change. However, 11‐KT produced both in tunica near BV and remaining follicle layer of degenerated oocyte possibly plays critical role during testicular differentiation as well as gonadal restructuring at mid to late phases (ET to LT) of sex change in honeycomb grouper. Mol. Reprod. Dev. © 2005 Wiley‐Liss, Inc.
Differential expression of transcriptional repressor snail gene at implantation site in mouse uterus
Authors: Ma Xing‐Hong , Hu Shi‐Jun , Yu Hao , Xu Li‐Bin , Yang Zeng‐Ming 
Published: October 2005

AbstractThe snail superfamily of zinc‐finger transcription factors is involved in pronounced cell movements during both embryonic development and tumor progression. This study was to examine snail expression in mouse uterus during early pregnancy and its regulation under pseudopregnancy, delayed implantation, steroid hormone treatment, and artificial decidualization by in situ hybridization and immunohistochemistry. There was a low level of snail mRNA signal and immunostaining in mouse uteri on day 1–4 of pregnancy. When embryo implanted on day 5, both snail mRNA signal and immunostaining were strongly detected in the subluminal stroma immediately surrounding the implanting blastocyst, but not detected in the inter‐implantation sites. Under delayed implantation, there was no detectable snail expression. After delayed implantation was terminated by estrogen treatment and embryo implanted, there was a strong level of snail mRNA and immunostaining in the subluminal stroma surrounding the implanting blastocyst, which was similar to that on day 5 of pregnancy. Furthermore, there was no detectable snail expression in mouse uterus on day 5 of pseudopregnancy. From day 6–8 of pregnancy, both snail mRNA signal and immunostaining were detected in the decidua. Our data suggest that snail may play an important role during mouse embryo implantation. Mol. Reprod. Dev. © 2005 Wiley‐Liss, Inc.
Recurrent ependymoma treated with high‐dose tamoxifen in a peripubertal female: Impact on tumor and the pituitary–ovarian axis
Authors: Yoffe Rona , Khakoo Yasmin , Dunkel Ira J. , Souweidane Mark , Lis Eric , Sklar Charles 
Published: October 2005

AbstractDue to high rates of recurrence, the prognosis of childhood ependymoma remains guarded. Anecdotal evidence suggests that tamoxifen may have a role in the treatment of these tumors. We present a case of a child with recurrent ependymoma treated with tamoxifen who showed tumor regression on two separate occasions. However, treatment with tamoxifen resulted in the development of large ovarian cysts associated with supraphysiological plasma concentrations of estradiol. Pediatr Blood Cancer 2007;49:758–760. © 2005 Wiley‐Liss, Inc.
Health‐related quality of life in children and emotional reactions of parents following completion of cancer treatment
Authors: Stam Heleen , Grootenhuis Martha A. , Brons Paul P.T. , Caron Huib N. , Last Bob F. 
Published: October 2005

AbstractBackgroundCompleting therapy is one of the major transitions in care in the practice of pediatric oncology and, therefore, deserves special consideration. The purpose of the study was to investigate health‐related quality of life (HRQOL) of pediatric patients, and emotional reactions of their parents, shortly after the end of successful treatment.MethodsHRQOL of 126 patients, aged 1–15 years, on average 2 months after the end of successful treatment, was assessed with the TNO‐AZL Pre‐school Quality of life Questionnaire and the TNO‐AZL Children's Quality of life Questionnaire. Emotional adjustment of 124 mothers and 111 fathers was assessed with the General Health Questionnaire and the Situation Specific Emotional Reaction Questionnaire. The outcomes of the patients and parents were compared with norm data by means of one sample t‐tests, one sample sign‐tests or binomial tests.ResultsAll age groups, except patients aged 8–11 years, experienced worse HRQOL than the norm with respect to motor functioning. In addition, pre‐school patients were rated worse on sleeping, appetite, stomach, skin, problem behavior, anxiety, and liveliness, and patients aged 6–7 years on autonomy and cognitive functioning. Parents reported more psychological distress than the norm. Compared to parents whose children were 1–5 years after cancer treatment, they suffered more from feelings of loneliness, helplessness, and uncertainty.ConclusionsA few months after the end of successful cancer treatment, both patients and parents appeared to experience worse well‐being than the norm to a clinically relevant extent. Supporting patients and parents should not stop when treatment ends. Pediatr Blood Cancer 2006;47:312–319. © 2005 Wiley‐Liss, Inc.
Gelation mechanism and microstructure of organogels formed with various types of gelators
Authors: Okabe Satoshi , Hanabusa Kenji , Shibayama Mitsuhiro 
Published: October 2005

AbstractThe small‐angle neutron scattering (SANS) and dynamic light scattering (DLS) investigation were carried out for organogels in toluene, formed by organogelators, to elucidate the relationship between the chemical structure and the gelation mechanism as well as the physical properties of the gels. Three different organogelators, that is cyclo(L‐β‐3,7‐dimethyloctylasparaginyl‐L‐phenylalanyl) (CPA), trans‐(1R,2R)‐bis(undecylcarbonylamino)cyclohexane (TCH), and Nε‐lauroyl‐Nα‐stearylaminocarbonyl‐L‐lysine ethyl ester (LEE), were chosen for comparison. The SANS intensity functions of toluene solutions of these gelators could be reduced with the concentration and were described with a scattering function for thin rods. This indicates that the gels consist of noncorrelated, rod‐like elements aggregated to each other. The characteristic features of the gelation properties, such as the critical gelation concentration, Cgel, the gelation temperature, Tgel, the gel structure, and the gelation mechanism, were different from each other. CPA had the lowest Cgel and became a gel gradually as the temperature decreased, while TCH and LEE had higher Cgels and underwent a sharp sol–gel transition. We conclude that the gelation mechanisms between the CPA and TCH solutions are different. The “CPA type” gelators form a gel by a linear extension of hydrogen‐bonded plane, while the “TCH type” gelators form a twisted wire, because of its strong helicity and crystallizability. In addition, in the latter type, a next generation of fibrils easily stacks on top of the previous ones to form larger fibrils. These models well explain the DLS results and the mechanical properties. That is, the fibrillar stems in CPA gels are rather mobile and fragile, while those in TCH and LEE are frozen and brittle. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 3567–3574, 2005
Rheology and microstructures formation of immiscible model polymer blends under steady state and transient flows
Authors: Das N. C. , Wang H. , Mewis J. , Moldenaers P. 
Published: October 2005

AbstractViscoelastic properties of model immiscible blend were studied here under steady state condition at different initial conditions and transient flow conditions. The flow‐induced microstructure has been studied on these model blends. For this system, the elastic properties of the blend are mainly governed by the interface. Measurement of the dynamic modulus and of the first normal stress difference, both reflecting this enhanced elasticity, have been used to prove the blend morphology. The dynamic moduli after cessation of shear flow, the mean diameter of the disperse phase as generated by the shear flow, have been calculated using the model of Palierne. A procedure based on a direct fitting of the dynamic moduli with the model is compared with the one that uses a weight relaxation spectrum. On the other hand, the steady state normal stress data have been related to the morphology of the blend by means of Doi and Ohta model. The specific interfacial area is found to be inversely proportional to the ratio of interfacial tension over shear stress for the blend. The flow behavior during transient shear flow was also discussed. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 3519–3533, 2005
Simulation of mefenacet concentrations in paddy fields by an improved PCPF‐1 model
Authors: Watanabe Hirozumi , Takagi Kazuhiro , Vu Son Hong 
Published: October 2005

AbstractAn improved simulation model (PCPF‐1) has been evaluated for the prediction of the fate of mefenacet in an experimental paddy field. This model simulates the fate and transport of pesticide in paddy water and the top 1 cm of paddy soil. Observed concentrations of mefenacet in the paddy water and the surface soil exponentially decreased from their maximum concentrations of 0.70 mg litre−1 and 11.3 mg kg−1, respectively. Predicted mefenacet concentrations both in the water and surface soil were in excellent agreement with those measured during the first 2 weeks after herbicide application, but concentrations in paddy water were appreciably overestimated thereafter. The model simulated mefenacet losses through runoff, percolation and degradation to be respectively 41.9%, 6.4% and 57.3% of applied, and the mass balance error was about −6%. The model simulation implied that drainage and seepage control, especially shortly after application when herbicide concentrations are high, is essential for preventing pesticide losses from paddy fields. In focusing on pesticide concentrations in this early period the PCPF‐1 model can be a beneficial tool for risk assessment of pesticide losses and in the evaluation of agricultural management for reducing pesticide pollution associated with paddy rice production. Copyright © 2005 Society of Chemical Industry
Impact of cypermethrin on feeding behaviour and mortality of the spider Pardosa amentata in arenas with artificial ‘vegetation’
Authors: Shaw Emma M , Waddicor Michelle , Langan A Mark 
Published: October 2005

AbstractPesticides can modify invertebrate movement and feeding behaviour which could reduce predation in agroecosystems. Previous assays have exposed the spider Pardosa amentata (Clerck) to the synthetic pyrethroid cypermethrin and monitored prey items consumed in small containers (requiring very little movement to capture prey). The current study used larger arenas containing artificial ‘vegetation’ (a plastic analogue) to encourage spiders to hunt and capture prey. The period 24 h after exposure produced greatest variability in prey item consumption between treatments and was used to examine treatment effects. At this time, cypermethrin reduced prey consumption rates but these effects did not persist. Findings did not suggest that the presence of artificial vegetation in arenas modified prey consumption rates, which was consistent for individuals treated with cypermethrin and a control group. This is despite the majority of pesticide‐treated individuals exhibiting both ataxia and paralysis of the hind legs (these effects persisting for a maximum of 3 and 6 days respectively). These findings were consistent for both sexes. Spider longevity under starvation conditions was not significantly reduced by cypermethrin exposure but overall females survived longer than males. The findings are discussed in the context of the arenas used and the ecology of this common predator. Copyright © 2005 Society of Chemical Industry