bluuebunny/crossref_metadata_2025_split huggingface dataset:
Superacid‐Promoted Cyclodehydration Leading to the Imidazo[2,1‐a]isoquinoline Ring System
Authors: Kethe Anila , Naredla Rajasekhar Reddy , Klumpp Douglas A. 
Published: August 2013

AbstractA series of heterocycle‐substituted acetophenones were prepared and reacted with the Brønsted superacid CF3SO3H (triflic acid=trifluoromethanesulfonic acid). Cyclodehydration provided aryl‐substituted imidazo[2,1‐a]isoquinolines and related products (28–85%, seven examples). A mechanism is proposed involving dicationic intermediates.
Stereoselective Synthesis of (−)‐(1R,1′R,5′R,7′R)‐1‐Hydroxy‐exo‐brevicomin and (+)‐exo‐Brevicomin from 3,4,6‐Tri‐O‐acetyl‐D‐glucal
Authors: Sabitha Gowravaram , Maheswara Reddy Arekuti , Siva Sankara Reddy Singam , Singh Yadav Jhillu 
Published: August 2013

AbstractStereoselective syntheses of (−)‐(1R,1′R,5′R,7′R)‐1‐hydroxy‐exo‐brevicomin (1) and (+)‐exo‐brevicomin (2) were accomplished from 3,4,6‐tri‐O‐acetyl‐D‐glucal (5; Schemes 2 and 3). Chemoselective reduction, Grignard reaction, BartonMcCombie deoxygenation, and ketalization were used as key steps.
Influence of a coarse interlayer on seawater intrusion and contaminant migration in coastal aquifers
Authors: Liu Yi , Mao Xiaomin , Chen Jian , Barry D. A. 
Published: August 2013

AbstractVertical 2D slice laboratory experiments were carried out in homogenous and layered sand tanks to elucidate the effects of a highly permeable (coarse‐grained sand) interlayer on seawater intrusion and transport of contaminants to a coastal sea. Tidal fluctuations produced oscillations in the seawater–freshwater transition zone, fluctuations of the contaminant infiltration rate and a zigzag contaminant plume outline. The seawater wedge became discontinuous at the (vertical) edges of the interlayer because of increased lateral movement of the seawater–freshwater interface within the interlayer. The contaminant plume formed a tail within the interlayer depending on the tidal stage, and similar to the wedge, its movement was accentuated. A simple analytical model that neglected vertical flow reliably predicted steady‐state seawater intrusion into the coastal aquifer. Numerical modeling was used to gain insight into the groundwater hydrodynamics and contaminant migration. The numerical results confirmed the experimental findings, i.e. that a highly permeable interlayer can provide a rapid transit path for contaminants to reach the seaward boundary and that the interlayer amplifies the effects of tidal fluctuations, resulting in wider transition zones for the seawater wedge and contaminant plume. Numerical simulations further showed that, with increasing interlayer hydraulic conductivity, the maximum seawater intrusion distance inside the interlayer increases approximately linearly. For the fixed‐head contaminant injection condition used, the model showed that contaminant infiltration increases approximately logarithmically with increasing interlayer hydraulic conductivity (other factors held fixed). Copyright © 2013 John Wiley & Sons, Ltd.
Factors affecting the measurement of the vertical hydraulic conductivity of a streambed sediment using standpipe tests
Authors: Huang Yong , Zhou Zhifang , Guo Qiaona , Tang Yuzhou , Lu Wenlong 
Published: August 2013

AbstractThe vertical hydraulic conductivity (Kv) of a stream or lake sediment is often determined in the field using standpipe tests. Calculation of Kv is based on the assumption that the hydraulic head in the pipe is equal to that of the stream or lake stage. In this work, a modified equation for Kv is developed for the standpipe test which is applicable when this assumption is not valid. The equation involves not only the hydraulic head at different times but also the difference in the hydraulic head (a) between the groundwater level and river stage. The effects of certain factors on Kv, such as the ratio of the hydraulic head at different times (h1/h2), the difference a, and the initial water table height (h0), are also discussed. The results show that when h1/h2 is constant, the relative error (Er) in Kv increases with the ratio a/h2. Furthermore, if a/h2  <  0.05, then for any value of h1/h2, Er is less than 5% using the modified equation. Also, if a/h2 is large, hydraulic head readings with larger h1/h2 ratios must be used to avoid large Er values. The results of a field test also indicate that the error in Kv decreases as the value of h0 increases. Copyright © 2013 John Wiley & Sons, Ltd.
Spatial, seasonal, and source variability in the stable oxygen and hydrogen isotopic composition of tap waters throughout the USA
Authors: Landwehr Jurate M. , Coplen Tyler B. , Stewart David W. 
Published: August 2013

AbstractTo assess spatial, seasonal, and source variability in stable isotopic composition of human drinking waters throughout the entire USA, we have constructed a database of δ18O and δ2H of US tap waters. An additional purpose was to create a publicly available dataset useful for evaluating the forensic applicability of these isotopes for human tissue source geolocation. Samples were obtained at 349 sites, from diverse population centres, grouped by surface hydrologic units for regional comparisons. Samples were taken concurrently during two contrasting seasons, summer and winter. Source supply (surface, groundwater, mixed, and cistern) and system (public and private) types were noted. The isotopic composition of tap waters exhibits large spatial and regional variation within each season as well as significant at‐site differences between seasons at many locations, consistent with patterns found in environmental (river and precipitation) waters deriving from hydrologic processes influenced by geographic factors. However, anthropogenic factors, such as the population of a tap's surrounding community and local availability from diverse sources, also influence the isotopic composition of tap waters. Even within a locale as small as a single metropolitan area, tap waters with greatly differing isotopic compositions can be found, so that tap water within a region may not exhibit the spatial or temporal coherence predicted for environmental water. Such heterogeneities can be confounding factors when attempting forensic inference of source water location, and they underscore the necessity of measurements, not just predictions, with which to characterize the isotopic composition of regional tap waters. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.
Comparing hydraulic properties of different forest floors
Authors: Rasoulzadeh Ali , Homapoor Ghoorabjiri Majid 
Published: August 2013

AbstractThe forest floor plays an important role in runoff rate, soil erosion and soil infiltration capacity by protecting mineral soils from the direct impact of falling raindrops. Forest floor consists of different kinds of litter with different hydraulic properties. In this study, the inverse method was used to estimate the hydraulic properties of three kinds of forest floor (broad‐leaved, needle‐leaved and mixed‐stand) at three replications in a completely random design. Forest floor samples were collected from the Gilan Province, Iran. The samples were piled up to make long columns 40.88 cm high with an inner diameter of 18.1 cm. Artificial rainfall experiments were conducted on top of the columns, and free drainage from the bottom of the columns was measured in the laboratory. Saturated hydraulic conductivity (Ks), saturated water content and water retention curve parameters (van Genuchten equation) were estimated by the inverse method. The results showed that the Ks of needle‐leaved samples differed significantly (p < 0.05) from those of broad‐leaved and mixed‐stand samples, whereas the latter two did not differ in this regard. No significant differences emerged in the water retention function parameters of van Genuchten (θr, β and α) in the three forest floor samples. The saturated water content of mixed‐stand samples was significantly different (p < 0.05) from that of broad‐leaved and needle‐leaved treatments with the latter two samples showing no significant difference. The good agreement between simulated and observed free drainage for all forest floor samples in the validation period indicates that the estimated hydraulic properties efficiently characterize the unsaturated water flow in the forest floor. Copyright © 2013 John Wiley & Sons, Ltd.
Assessing effects of PCB exposure on American mink (Mustela vison) Abundance in Portland Harbor
Authors: Luxon Matt , Toll John , Hanson Craig 
Published: August 2013

Abstract
This article presents an integrated analysis using a Monte Carlo exposure model, dose–response effects model and habitat, and population dynamics models, all of which allow us to quantitatively estimate the effects of polychlorinated biphenyl (PCB) exposure on American mink (Mustela vison) abundance at the Portland Harbor Superfund Site (Site), and the associated uncertainties. The Site extends from river mile 1.9 of the Lower Willamette River, near its confluence with the Columbia River, to river mile 11.8, just downstream of downtown Portland, Oregon. The potential effects of PCBs on the American mink population were evaluated in the Baseline Ecological Risk Assessment (BERA) due to the historical presence of mink in the area and because mink are known to be highly sensitive to the effects of PCBs. Hazard quotients (HQs) calculated in the BERA indicated that PCB concentrations measured in Portland Harbor fish were above levels known to cause reproductive effects in mink. Further analysis was needed to evaluate the potential magnitude of effects on the Site mink population. The integrated analysis presented herein demonstrates that if an effect of PCB exposure is a less than 30% reduction in kit production, then PCB remediation is not expected to have any effect on mink abundance. This is a Site-specific conclusion that depends on the quality, abundance, and distribution of mink habitat in Portland Harbor. The PCB dose associated with a 30% reduction in kit production was calculated as 101 μg/kg bw/d (90% CI = 69–146 μg/kg bw/d). The mink PCB dose estimates from the Portland Harbor BERA indicate that if mink are present, their baseline exposure levels probably exceed 101 μg/kg bw/d. Therefore, some level of reduction in PCB exposure could be beneficial to the species if the study area provides sufficient habitat to support a mink population. This analysis demonstrates that risk analysis for population-level assessment endpoints benefits from analyses beyond those that calculate exposure and predict organism-level effects. Evaluation of population-level impacts provides risk managers with a richer perspective within which to evaluate the environmental protectiveness and cost-effectiveness of feasibility study alternatives across a range of potential remediation goals. Integr Environ Assess Manag 2013;X:000–000. © 2013 SETAC Integr Environ Assess Manag 2013;9999:XX–XX. © 2013 SETAC Integr Environ Assess Manag 2014;10:60–68. © 2013 SETAC
UNRAVELLING THE SPATIO‐TEMPORAL PATTERN OF IRRIGATION DEVELOPMENT AND ITS IMPACT ON INDIAN AGRICULTURE
Authors: Srivastava Shivendra K. , Ghosh Souvik , Kumar Ashwani , Brahmanand Pothula S. 
Published: August 2013

ABSTRACTIrrigation, the dominant use of water resources, has always remained a decisive factor in agricultural growth and development. The present study provides a critical analysis of inter‐regional variations in water resources and irrigation development over successive plan periods (1950–2007) and ascertains the long‐term impact of irrigation development on Indian agriculture using tabular, growth and econometric analysis. With impressive irrigation development over successive five‐year plans, India possesses the largest irrigated area in the world. However, the positive impact of irrigation development could not be achieved equally across different geographical regions, and unsustainable water resource development in one part coexists with its underutilization in other parts of the country. The Northern region of India showed better performance both in irrigation and agriculture while the Eastern region was found to be poorest in spite of a rich water resource base. Panel data analysis revealed a positive correlation between irrigation and crop yield though with varying degree. The findings of the present study provides a platform for institutional restructuring, policy reframing and technological interventions to improve water use efficiency and develop water resources in a equitable, holistic and sustainable manner. Copyright © 2013 John Wiley & Sons, Ltd.
Multiple‐dose, safety, pharmacokinetic, and pharmacodynamic study of sotatercept (ActRIIA‐IgG1), a novel erythropoietic agent, in healthy postmenopausal women
Authors: Sherman Matthew L. , Borgstein Niels G. , Mook Louisa , Wilson Dawn , Yang Yijun , Chen Nianhang , Kumar Ravindra , Kim Kenneth , Laadem Abderrahmane 
Published: August 2013

AbstractLigands of the transforming growth factor‐beta superfamily and activin‐receptor signaling play an important role in erythropoiesis. Sotatercept, an activin receptor type IIA (ActRIIA) ligand trap, is a novel, recombinant, fusion protein comprising the extracellular domain of human ActRIIA linked to the Fc portion of human immunoglobulin G1. Sotatercept, originally developed to increase bone mineral density, was noted to have robust effects on erythropoiesis. Here, we evaluated the safety, pharmacokinetic properties, and pharmacodynamic effects of sotatercept in 31 healthy postmenopausal women. Sotatercept was administered at dose level 0.1, 0.3, or 1 mg/kg every 28 days subcutaneously for up to four doses. Sotatercept was generally safe and well tolerated, and elicited clinically significant, dose‐dependent increases in hemoglobin, hematocrit, and red blood cell counts that persisted for up to 4 months. The effect of sotatercept on hemoglobin was dose‐limiting. Sotatercept also increased bone mineral density and biomarkers of bone formation. The sotatercept serum exposure–dose relationship was linear, with a mean terminal half‐life of approximately 23 days. ActRIIA ligands are important regulators of erythrocyte production in healthy individuals. Clinical studies are ongoing to explore the potential of sotatercept to treat anemia and diseases of ineffective erythropoiesis as well as an agent to increase bone mineral density.
Reduced exposure variability of the CYP3A substrate simvastatin by dose individualization to CYP3A activity
Authors: Stoll Felicitas , Burhenne Jürgen , Lausecker Berthold , Weiss Johanna , Thomsen Torben , Haefeli Walter Emil , Mikus Gerd 
Published: August 2013

AbstractThis study aimed to demonstrate that the dose of a CYP3A substrate (simvastatin) can be adapted individually on the basis of CYP3A activity as assessed by midazolam metabolic clearance. In 18 healthy participants individual CYP3A activity was quantified using midazolam metabolic clearance both alone and during CYP3A inhibition with 40 mg ritonavir. Thereafter, simvastatin acid exposure was determined after a simvastatin standard dose (40 mg) and doses adapted to individual CYP3A activity at baseline and during CYP3A inhibition. Interindividual variability of CYP3A activity and simvastatin acid AUC0–24 was large and both correlated (r2 = 0.745, P < .001). The adapted simvastatin doses ranged from 25 to 80 mg and their administration reduced simvastatin variability fivefold. Despite the low adapted simvastatin dose of 12 mg during CYP3A inhibition with ritonavir, exposure increased (point estimate of 4.2 [90% CI: 3.15–5.61]) probably caused by additional OATP1B1 inhibition. CYP3A activity‐based dose adaptation can be used to reduce interindividual variability in simvastatin exposure.
Application limits and data correction in number of molecules and brightness analysis
Authors: Trullo Antonio , Corti Valeria , Arza Elvira , Caiolfa Valeria R. , Zamai Moreno 
Published: August 2013

ABSTRACTNumber of molecules and Brightness (N&B) has been proposed for measuring the molecular brightness and number of fluorophores in time‐sequence of images, in live cells. If the fluorescently tagged‐proteins are mobile in the illumination volume, the stoichiometry of their oligomers can be derived from the increase of the brightness of the fluorescent dyes due to clustering. We examine aspects concerning extra‐fluctuation effects induced by cell shifts and photobleaching, which yield large overestimates of the clusters size and sub‐unit counts. We develop an offline corrective approach consisting in frame re‐alignment and boxcar filtering for recovering precision of the analysis. Using simulations we derive general criteria for approaching this analysis, and assess the application limits of the corrective procedure. We tested the approach in extreme experimental conditions (few pixels, large extra‐variance perturbations), in which we analyzed the minimal increases of brightness as that expected between a monomeric and dimeric GPI‐mEGFP constructs. We show how most of the perturbing effects can be abolished, and obtain the correct the brightness of GPI‐mEGFP monomers and dimers. Microsc. Res. Tech. 76:1135–1146, 2013. © 2013 Wiley Periodicals, Inc.
Application of wavelet empirical orthogonal function analysis to investigate the nonstationary character of Ethiopian rainfall and its teleconnection to nonstationary global sea surface temperature variations for 1900–1998
Authors: Elsanabary Mohamed Helmy , Gan Thian Yew , Mwale Davison 
Published: August 2013

ABSTRACTThis study employed the wavelet empirical orthogonal function (WEOF) analysis to analyse the nonstationary variability of rainfall in Ethiopia and global sea surface temperature (SST) for 1900–1998. The study found that the nonstationary variations of both the June to September (JJAS) and February to May (FMAM) Ethiopian rainfall can be delineated into three zones: western half of Ethiopia north of the Great Rift Valley (GRV), southern Ethiopia south of the GRV and the GRV from southwestern Ethiopia to the Afar Triangle. The leading wavelet principal component (WPC) signals showed that Ethiopian rainfall had been in stagnation for most of 1900–1998, with major droughts in the 1940s and 1980s. The dominant frequencies of Ethiopian rainfall ranged between 2 and 8 years. In western Ethiopia, the 2–4‐year rainfall frequencies dominated the rainfall variation, but their trends are modulated by 5–7‐year frequencies, whereas in the Afar Triangle, the 5–7‐year frequencies were dominant. Between 1900 and 1998, the Afar Triangle region experienced decreasing rainfall for 60 years (1900–1960). The seasonal global SST revealed that regardless of what time of the year, the strongest contributions to global SST variations occur in the Antarctic Ocean, the El Niño region of South America and in the southwestern Pacific Ocean, followed by the Atlantic and the Indian Oceans. Further, this study also shows annual migrations of SST variations in the El Niño region, the Antarctic and the Atlantic Oceans. The leading SST signal variations show that SST warming started in the Atlantic and Indian Oceans, from 1950 to 1975, and spread to the Antarctic Ocean between 1960 and 1990, which probably contributed to the melting of sea ice. Teleconnections between WPC1 of Ethiopian rainfall and SST scale‐averaged wavelet power were found for the El Niño region and northern Atlantic, west of the Sahara desert.
Observed surface wind speed in the Tibetan Plateau since 1980 and its physical causes
Authors: You Qinglong , Fraedrich Klaus , Min Jinzhong , Kang Shichang , Zhu Xiuhua , Pepin Nick , Zhang Ling 
Published: August 2013

ABSTRACTClimate warming on the Tibetan Plateau (TP) potentially influences many climate parameters other than temperature including wind speed, cloudiness and precipitation. Temporal trends of surface wind speed at 71 stations above 2000 m above sea level in the TP are examined during 1980–2005. To uncover causes of observed trends in wind speed, relationships with surface temperature, a TP index and sunshine duration are also analysed. The TP index is calculated as the accumulated 500 hPa geopotential height above 5000 m over the region of 30°N–40°N, 75°E–105°E from NCEP/NCAR reanalysis. The annual mean wind speed patterns during 1980–2005 are similar to those in different seasons, with higher wind speeds in the northern and western parts of the TP. Highest mean wind speeds occur in spring and lowest in autumn. During 1980–2005, annual and seasonal mean wind speeds show statistically decreasing trends at most stations. The mean trend magnitude for annual mean wind speed is −0.24 m s−1 decade−1, with the maximum decline in spring (−0.29 m s−1 decade−1) and minimum in autumn (−0.19 m s−1 decade−1). Both annually and in different seasons, wind speed is significantly negatively correlated with mean temperature, minimum temperature, maximum temperature, and the TP index, but significantly positively correlated with sunshine duration. Wind speed trends fail to show a simple elevation dependency but speeds are positively correlated with meridional surface temperature/pressure gradients. Warming in the TP may weaken the latitudinal gradients of both regional temperature and surface pressure, thus altering the regional atmospheric circulation and accounting in part for the observed decline of wind speed.
A stable‐isotope methodology for measurement of soil‐applied zinc‐fertilizer recovery in durum wheat (Triticum durum)
Authors: McBeath Therese M. , McLaughlin Michael J. , Kirby Jason K. , Degryse Fien 
Published: August 2013

AbstractA growth‐chamber study was used to develop a zinc stable‐isotope (67Zn) tracing technique to directly measure the amount of soil‐applied zinc (Zn) granular fertilizer taken up by durum wheat (Triticum durum L.) in four different soil types. The 67Zn‐tracer technique was then applied under field conditions at one site to test the ability of the method to measure the crop recovery of soil‐applied Zn granular fertilizer (67Zn). The technique was developed by comparing plants treated with nil Zn fertilizer to natural‐abundance‐Zn‐coated fertilizer and 67Zn‐coated fertilizer with plant parts analyzed for Zn isotopic composition using inductively coupled plasma–mass spectrometry. Zinc‐fertilizer recovery under growth‐chamber conditions was inversely related to the concentration of labile Zn in soils, with the plants on the most Zn‐deficient soils having the greatest amount of Zn derived from the added fertilizer. Zinc derived from fertilizer ranged from 0.3% (Luvisol) to 0.6% (Solonetz) to 13% (Calcisol) and 18% (Lixisol) for soils with DTPA‐extractable Zn of 3.5–0.21 mg kg–1. Across the experiments, fertilizer recovery was measurable but very low (< 1% of added fertilizer being recovered by durum wheat). The recovery of Zn added to the Luvisol was slightly higher in the field than in the glasshouse (but all < 0.1%). Using this stable‐isotope technique, it was possible to directly assess the supply of soil‐applied Zn fertilizers to crop plants.