bluuebunny/crossref_metadata_2025_split huggingface dataset:
Plant availability of boron in acid soils as assessed by different extractants
Authors: Sarkar Dibyendu , Mandal Biswapati , Mazumdar Debasis 
Published: April 2008

AbstractEstimation of available‐boron (B) status through conventional methods in B‐deficient acidic Inceptisols and Entisols is often hampered because of their very low B content. In the present study, the extractability of available B by different extractants was tested in relation to soil properties. Plant availability of B was assessed with mustard (Brassica campestris L.) and wheat (Triticum aestivum L.) in pot experiments. Twelve soils with varying characteristics were extracted for available B with hot water (HW), hot CaCl2 (HCC), KH2PO4 (PDP), tartaric acid (TA), and mannitol‐CaCl2 (MCC). Mustard (cv. B‐9) and wheat (cv. PBW‐343) were grown with four levels of B (0, 0.25, 0.50, and 1.0 mg [kg soil]–1). Dry‐matter accumulation and B concentrations were determined at pre‐flowering and full‐maturity stages for mustard and at panicle‐initiation and maturity stages for wheat. The extraction of B from the soils ranked HCC > HW > PDP > TA > MCC. The higher extractability with HW and HCC was likely due to higher temperature and that of PDP because of its phosphorus content, which facilitated the desorption of B. The low B extraction with MCC resulted from the poor mannitol‐B complex formation in acidic soils. The application of B increased dry‐matter accumulation, plant B concentration, and uptake at all B levels and growth stages in both crops with the responses being more pronounced during the early developmental stage. Based on linear correlations, Mallow's Cp statistics, and principal‐component analyses, HCC and HW were the best extractants for estimating available B in the acidic experimental soils.
Effects of nitrogen supply on water‐use efficiency of higher plants
Authors: Brueck Holger 
Published: April 2008

AbstractThe worldwide increase of food demand and reduced sweet‐water availability in some important food‐producing regions raised interest in more efficient water use, which has become one of the central research topics in agriculture. Improved irrigation management and reduced bare‐soil evaporation have highest priority to increase agronomic water‐use efficiency (WUE). Compared to these technical (irrigation) and basic (crop production) management options, effects of nutrient management on WUE were less frequently considered. Twenty‐nine publications on nitrogen (N) effects on biomass WUE of container‐grown plants are considered in this review. Most of them indicate positive N effects on WUE, and relevance of N effects on intrinsic WUE and unproductive water and carbon loss is discussed. A plot of 90 published data of percent decreases of WUE and dry mass under variable N supply is presented. Extrapolation of biomass WUE from leaf measurements of intrinsic WUE is critically reviewed. The positive correlation between WUE and dry‐mass formation suggests that physiological rather than stomatal effects are more important in order to explain positive N effects on WUE.
Genotypic variation in grain mercury accumulation of lowland rice
Authors: Zhu Cheng , Shen Guoming , Yan Yuping , He Junyu 
Published: April 2008

AbstractA pot experiment with 38 commonly cultivated rice cultivars from the Yangtze River Delta was conducted in a greenhouse to study the effect of mercury (Hg) contamination of a paddy soil (4.7 mg Hg [kg soil]–1) on crop growth and Hg accumulation in the grains. Mercury contamination differentially affected growth, grain yield, and Hg accumulation in brown rice of the tested cultivars. The average Hg concentration in the grains was significantly higher (p < 0.01) when plants were grown in the Hg‐contaminated compared to the control soil. Averaged over cultivars, the Hg concentration in brown rice exceeded the maximum permissible limit of 20 μg Hg kg–1. Increasing Hg concentrations were associated with grain‐yield declines up to 70%. This yield decline was mainly due to a reduction in the number of panicles. Japonica cultivars tended to be generally less affected by Hg than indica cultivars. The two japonica cultivars Jiahua and Chunjiang 026 showed both low Hg concentrations and no Hg‐induced grain‐yield reduction. These cultivars may be preferred candidates for cultivation in Hg‐contaminated soils or for studies on possible Hg‐exclusion mechanisms.
Effect of crop‐residue management on the production and agronomic nitrogen efficiency in a rice–wheat cropping system
Authors: Sharma S. N. , Prasad Rajendra 
Published: April 2008

AbstractThe rice–wheat cropping system (RWCS), producing about 5–10 Mg ha–1 y–1 of grain, is the backbone of food‐crop production in South‐East Asia. However, this system shows signs of fatigue as indicated by declining yields, negative nitrogen (N) balances, and reduced responses to applied fertilizer at some research centers. The return of rice and wheat residues can recycle up to 20%–30% of the N absorbed by the crops. However, their wide C : N ratio can temporarily immobilize native and applied N. To overcome this immobilization, wheat‐straw application was supplemented with the incorporation of Sesbania green manure and mungbean residues, and their effects on productivity, agronomic N efficiency, and system's apparent N balances were studied. Combining the application of wheat straw with Sesbania green manure or mungbean residues increased cereal grain yield and agronomic N efficiency and improved the generally negative apparent N balances. The combined use of wheat straw and mungbean produced an additional 0.5–0.6 t ha–1 protein‐rich grain and thus appears to be the most promising residue‐management option for rice–wheat cropping systems in South Asia, provided that the transition cropping season between wheat harvest and rice transplanting is long enough.
Inversion of TDR signals—revisited
Authors: Bänninger Dominik , Wunderli Hans , Nussberger Mathis , Flühler Hannes 
Published: April 2008

AbstractIn this study, we discuss the consistence of measured and calculated TDR traces. The calculated traces are solutions of a time domain reflectometry (TDR) forward solver, an algorithm for computing the TDR trace for a given dielectric profile along a transmission line. An unambiguous and efficient forward solver is a prerequisite for a good solution of the inverse problem, i.e., to extract the spatial distribution of the dielectric properties along the transmission line from a TDR trace. To advance our understanding of TDR inversion, we proceeded in two steps: (1) design of a TDR head section with minimal disturbances on the signal and (2) searching for causes why measured and predicted TDR traces differ. Based on a first experiment with a three‐rod TDR probe of 100 cm length, we demonstrated that our TDR forward solver—like others presented in literature—approximate the measured TDR traces apparently well but not precisely enough for signal inversion. In a second experiment, using a two‐rod TDR probe of 70 cm length, we addressed the problem of non‐parallel transmission lines. We found that the influence of a non‐parallel installation is similar to an increase of the electrical conductivity in soil water but can be distinguished from this property. A third experiment reveals that lateral and longitudinal disturbances in the vicinity of a TDR probe are of minor importance. From the analysis of our experiments, we found that neither lateral disturbances nor non‐parallel rods are responsible for the deviations between calculated and measured traces. This analysis showed us that structure in the sampled medium affects the shape of the TDR traces. Since minor deviations are essential for TDR‐signal inversion, we need new concepts to handle the fuzziness between measurements and calculations.
Phosphorus acquisition and wheat growth are influenced by shoot phosphorus status and soil phosphorus distribution in a split‐root system
Authors: Ma Qifu , Rengel Zed 
Published: April 2008

AbstractRoot proliferation and greater uptake per unit of root in the nutrient‐rich zones are often considered to be compensatory responses. This study aimed to examine the influence of plant phosphorus (P) status and P distribution in the root zone on root P acquisition and root and shoot growth of wheat (Triticum aestivum L.) in a split‐root soil culture. One compartment (A) was supplied with either 4 or 14 mg P (kg soil)–1, whereas the adjoining compartment (B) had 4 mg P kg–1 with a vertical high‐P strip (44 mg kg–1) at 90–110 mm from the plant. Three weeks after growing in the split‐root system, plants with 4 mg P kg–1 (low‐P plants) started to show stimulatory root growth in the high‐P strip. Two weeks later, root dry weight and length density in the high‐P strip were significantly greater for the low‐P plants than for the plants with 14 mg P (kg soil)–1. However, after 8 weeks of growth in the split‐root system, the two P treatments of compartment A had similar root growth in the high‐P strip of compartment B. The study also showed that shoot P concentrations in the low‐P plants were 0.6–0.8 mg g–1 compared with 1.7–1.9 mg g–1 in the 14 mg P kg–1 plants after 3 and 5 weeks of growth, but were similar (1.1–1.4 mg g–1) between the two plants by week 8. The low‐P plants had lower root P concentration in both compartments than those with 14 mg P kg–1 throughout the three harvests. The findings may indicate that root proliferation and P acquisition under heterogeneous conditions are influenced by shoot P status (internal) and soil P distribution (external). There were no differences in the total root and shoot dry weight between the two P treatments at weeks 3 and 5 because enhanced root growth and P uptake in the high‐P strip by the low‐P plants were compensated by reduced root growth elsewhere. In contrast, total plant growth and total root and shoot P contents were greater in the 14 mg P kg–1 soil than in the low‐P soil at week 8. The two P treatments did not affect the ratio of root to shoot dry weight with time. The results suggest that root proliferation and greater P uptake in the P‐enriched zone may meet the demand for P by P‐deficient plants only for a limited period of time.
Crystal and molecular structure of 2‐amino‐5‐chloropyridinium hydrogen selenate—its IR and Raman spectra, DFT calculations and physicochemical properties
Authors: Lorenc J. , Bryndal I. , Marchewka M. , Kucharska E. , Lis T. , Hanuza J. 
Published: April 2008

AbstractThe new organic‐inorganic salt, 2‐amino‐5‐chloropyridinium hydrogen selenate, has been synthesised and characterised by means of FT‐IR, FT‐Raman and single crystal X‐ray crystallography. Its vibrational spectra have been discussed on the basis of quantum chemical DFT calculations using the B3LYP/6‐31G(d,p) approach. The crystal and molecular structures have been compared and the role of the intermolecular interactions in this crystal has been analysed. The NHO interactions between the hydrogen atoms of the organic cation and oxygen atoms of hydrogen selenate anion determine the supramolecular arrangement in three‐dimensional space. The possible application of the studied composite material as a Raman laser has been discussed. Copyright © 2008 John Wiley & Sons, Ltd.
Analysis of seized drugs using portable Raman spectroscopy in an airport environment—a proof of principle study
Authors: Hargreaves Michael D. , Page Kristian , Munshi Tasnim , Tomsett Richard , Lynch Gary , Edwards Howell G. M. 
Published: April 2008

AbstractThe rapid identification for drugs‐of‐abuse in airports is of critical importance. In this study we demonstrate the viability of Raman spectroscopy for the rapid identification of illicit substances in their containers in an airport environment.Raman spectra of drugs‐of‐abuse in situ were collected using portable Raman spectrometers; this technique offers distinct advantages to government agencies, first responders and forensic scientists working in the security field. We have demonstrated that the spectrometers are able to collect the spectra of suspect powders, including cocaine HCl and d‐amphetamine sulphate with unknown constituents rapidly and with a high degree of discrimination. Copyright © 2008 John Wiley & Sons, Ltd.
Mouse oocytes derived from fetal germ cells are competent to support the development of embryos by in vitro fertilization
Authors: Shen Wei , Li Lan , Zhang Donghui , Pan Qingjie , Ding Mingxiao , Deng Hongkui 
Published: April 2008

AbstractFigure 1B in the paper above appeared to be an enlargement of a portion of Figure 1A, while the legend indicated otherwise. This error had been made because the authors labeled the sections by date, but not by source, and because experimental and control sections were similar.The authors have now confirmed their overall results and have submitted new figures for Figure 1 and Figure 4A presented below.The original article to which this erratum refers, was published in Molecular Reproduction and Development 2006;73(10):1312–1317. Mol. Reprod. Dev. 75: 1688–1689, 2008. © 2008 Wiley‐Liss, Inc.
Finding the one‐loop soliton solution of the short‐pulse equation by means of the homotopy analysis method
Authors: Parkes E.J. , Abbasbandy S. 
Published: April 2008

AbstractThe homotopy analysis method is applied to the short‐pulse equation in order to find an analytic approximation to the known exact solitary upright‐loop solution. It is demonstrated that the approximate solution agrees well with the exact solution. This provides further evidence that the homotopy analysis method is a powerful tool for finding excellent approximations to nonlinear solitary waves. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2009
The effectiveness of NGO self‐regulation: theory and evidence from Africa
Authors: Gugerty Mary Kay 
Published: April 2008

AbstractNon‐governmental organizations (NGOs) play an increasingly important role in public service provision and policy making in sub‐Saharan Africa, stimulating demand for new forms of regulatory oversight. In response, a number of initiatives in NGO self‐regulation have emerged. Using cross‐national data on 20 African countries, the article shows that self‐regulation in Africa falls into three types: national‐level guilds, NGO‐led clubs and voluntary codes of conduct. Each displays significant weaknesses from a regulatory policy perspective. National guilds have a broad scope, but require high administrative oversight capacity on the part of NGOs. Voluntary clubs have stronger standards but typically have much weaker coverage. Voluntary codes are the most common form of self‐regulation, but have the weakest regulatory strength. This article argues that the weakness of current attempts to improve the accountability and regulatory environment of NGOs stems in part from a mismatch between the goals of regulation and the institutional incentives embedded in the structure of most self‐regulatory regimes. The article uses the logic of collective action to illustrate the nature of this mismatch and the tradeoffs between the potential breadth and strength of various forms of NGO self‐regulation using three detailed case studies. Copyright © 2008 John Wiley & Sons, Ltd.
Polyurethane foam and fire safety
Authors: Hirschler M. M. 
Published: April 2008

AbstractThis paper presents a survey of the fire safety of flexible and rigid polyurethane foam. The principal uses of flexible polyurethane foam are in applications where full resiliency is required, namely in upholstery for furniture, mattresses, and filled bed products. A subcategory of this type of application is the use of the foam in transportation seating, including every type of vehicle: automobiles, buses (and school buses), trains (and subways), ships, and aircraft. The fire safety legally required for these various environments covers a broad range, between virtually nothing for private automobiles and the extreme fire safety associated with airplane seats. Polyurethane foam also forms part of construction products, and in this case the foam is generally not applied exposed (since this is almost never allowed) and is often used as part of composite systems. The fire testing is normally conducted in the composite application, with severe restrictions to general uses. Overall, polyurethane foam can be used safely for applications that require adequate fire safety only if it is appropriately fire‐retarded or if the correct type of fire barriers (or alternate product design) is used. Copyright © 2008 John Wiley & Sons, Ltd.
Prostate stem cells and benign prostatic hyperplasia
Authors: Isaacs John T. 
Published: April 2008

AbstractPharmacological approaches are available to medically‐managed patients with symptomatic BPH before surgical intervention is required. These include daily treatment with alpha‐blockers and 5‐alpha‐reductase inhibitors alone or in combination. These medical approaches have two major problems. First, treatments are chronic and must be taken daily. Second, there are significant financial costs and quality of life issues for such chronic treatments. Is it possible to develop effective acute therapy for symptomatic BPH without the long‐term androgen deprivation‐induced side effects? Two seminal but rarely cited studies of Walsh [Peters, Walsh: N Engl J Med 317:599–604, 1987] and Coffey et al. [Sufrin et al.: Invest Urol 13:418–423, 1976], combined with the growing understanding of the stem cell organization of the prostate stromal (S) and epithelial (E) compartments and their reciprocal paracrine and autocrine interactions provides the rationale for an acute approach.The Walsh study documents that: (1) androgen deprivation disrupts the reciprocal interaction between the prostate S and E thereby decreasing the weight of both compartments and (2) once BPH develops, androgen deprivation does not decrease the number of stem cell units in either the S or E compartments since subsequent androgen restoration fully restores the enlarged gland. The Coffey study documents that acute androgen deprivation sensitizes S–E interactions to radiation induced disruptions so that following radiation, androgen restoration does not induce full gland regrowth. Therefore, effective therapy for symptomatic BPH should be achievable by acute treatment with reversible androgen deprivation for a limited period followed by a single dose of conformal external beam radiation before allowing the man to recovery his normal serum testosterone. Prostate 68:1025–1034, 2008. © 2008 Wiley‐Liss, Inc.
Crystal structure of archaeal tRNA(m1G37)methyltransferase aTrm5
Authors: Goto‐Ito Sakurako , Ito Takuhiro , Ishii Ryohei , Muto Yutaka , Bessho Yoshitaka , Yokoyama Shigeyuki 
Published: April 2008

AbstractMethylation of the N1 atom of guanosine at position 37 in tRNA, the position 3′‐adjacent to the anticodon, generates the modified nucleoside m1G37. In archaea and eukaryotes, m1G37 synthesis is catalyzed by tRNA(m1G37)methyltransferase (archaeal or eukaryotic Trm5, a/eTrm5). Here we report the crystal structure of archaeal Trm5 (aTrm5) from Methanocaldococcus jannaschii (formerly known as Methanococcus jannaschii) in complex with the methyl donor analogue at 2.2 Å resolution. The crystal structure revealed that the entire protein is composed of three structural domains, D1, D2, and D3. In the a/eTrm5 primary structures, D2 and D3 are highly conserved, while D1 is not conserved. The D3 structure is the Rossmann fold, which is the hallmark of the canonical class‐I methyltransferases. The a/eTrm5‐defining domain, D2, exhibits structural similarity to some class‐I methyltransferases. In contrast, a DALI search with the D1 structure yielded no structural homologues. In the crystal structure, D3 contacts both D1 and D2. The residues involved in the D1:D3 interactions are not conserved, while those participating in the D2:D3 interactions are well conserved. D1 and D2 do not contact each other, and the linker between them is disordered. aTrm5 fragments corresponding to the D1 and D2‐D3 regions were prepared in a soluble form. The NMR analysis of the D1 fragment revealed that D1 is well folded by itself, and it did not interact with either the D2‐D3 fragment or the tRNA. The NMR analysis of the D2‐D3 fragment revealed that it is well folded, independently of D1, and that it interacts with tRNA. Furthermore, the D2‐D3 fragment was as active as the full‐length enzyme for tRNA methylation. The positive charges on the surface of D2‐D3 may be involved in tRNA binding. Therefore, these findings suggest that the interaction between D1 and D3 is not persistent, and that the D2‐D3 region plays the major role in tRNA methylation. © 2008 Wiley‐Liss, Inc.
Structure‐based mutagenesis of Penicillium griseofulvum xylanase using computational design
Authors: André‐Leroux Gwénaëlle , Berrin Jean‐Guy , Georis Jacques , Arnaut Filip , Juge Nathalie 
Published: April 2008

AbstractPenicillium griseofulvum xylanase (PgXynA) belongs to family 11 glycoside hydrolase. It exhibits unique amino acid features but its three‐dimensional structure is not known. Based upon the X‐ray structure of Penicillium funiculosum xylanase (PfXynC), we generated a three‐dimensional model of PgXynA by homology modeling. The native structure of PgXynA displayed the overall β‐jelly roll folding common to family 11 xylanases with two large β‐pleated sheets and a single α‐helix that form a structure resembling a partially closed right hand. Although many features of PgXynA were very similar to previously described enzymes from this family, crucial differences were observed in the loop forming the “thumb” and at the edge of the binding cleft. The robustness of the xylanase was challenged by extensive in silico‐based mutagenesis analysis targeting mutations retaining stereochemical and energetical control of the protein folding. On the basis of structural alignments, modeled three‐dimensional structure, in silico mutations and docking analysis, we targeted several positions for the replacement of amino acids by site‐directed mutagenesis to change substrate and inhibitor specificity, alter pH profile and improve overall catalytic activity. We demonstrated the crucial role played by Ser44PgXynA and Ser129PgXynA, two residues unique to PgXynA, in conferring distinct specificity to P. griseofulvum xylanase. We showed that the pH optimum of PgXynA could be shifted by −1 to +0.5 units by mutating Ser44PgXynA to Asp and Asn, respectively. The S44D and S44N mutants showed only slight alteration in Km and Vmax whereas a S44A mutant lost both pH‐dependence profile and activity. We were able to produce PgXynA S129G mutants with acquired sensitivity to the Xylanase Inhibitor Protein, XIP‐I. The replacement of Gln121PgXynA, located at the start of the thumb, into an Arg residue resulted in an enzyme that possessed a higher catalytic activity. Proteins 2008. © 2008 Wiley‐Liss, Inc.