bluuebunny/crossref_metadata_2025 huggingface dataset:
ChemInform Abstract: Theoretical and Physical Aspects of Nuclear Shielding
Authors: JAMESON C. J.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: NMR Spectroscopic Characterization of Vinyl Cations
Authors: SIEHL H.‐U.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: NMR Methods in Combinatorial Chemistry
Authors: SHAPIRO M. J. , WAREING J. R.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Identifying the preferable bancassurance alliance structure from the bank's executive management perspective: analytic network process application
Authors: Wu Cheng‐Ru , Lin Chin‐Tsai , Lin Yu‐Fan
Published: June 2010

This paper identifies the preferable bancassurance alliance structure from the bank's executive management perspective in the Taiwan area. In combination with the relevant literature and interviews with experts, this study adopts the modified Delphi method and the analytic network process (ANP) to construct an evaluation method and to determine ANP effectiveness. The results indicate that executives of banks and insurance companies most prefer financial holding companies. In this study, we apply ANP to construct an evaluation method and introduce four criteria and ten subcriteria for evaluating six alternative bancassurance alliance models. This paper supports ANP as an effective decision making tool. Copyright © 2010 ASAC. Published by John Wiley & Sons, Ltd.
Response Surface Approach for the Biosorption of Cr6+Ions byMucor racemosus
Authors: Jabasingh Sekarathil A. , Pavithra Garre
Published: June 2010

Response surface methodology (RSM) employing the Box‐Behnken design was used to optimize the biosorption of chromium (Cr6+) byMucor racemosusin submerged culture. The initial Cr6+concentration (20–100 mg/L), pH (3.0–7.0), biomass dosage (5.0–9.0 mg), and time of sorption (2.0–6.0 h) were chosen as the process variables for the optimization. Two response values were chosen, i.e., sorption capacity (mg/g) and sorption percentage are optimized. A four‐factor‐three‐level Box‐Behnken design was used to evaluate the effects of these parameters on the sorption percentage. A second‐order quadratic model suggested the optimum conditions (initial Cr6+concentration 100 mg/L, pH of 5.0, biomass dosage of 5.0 mg, and time of sorption 4 h) resulted in the improvement of sorption of Cr6+from 12.47 to 49.98% as well as the improvement of the sorption capacity from 0.1036 to 0.5 mg/g. Analysis of variance (ANOVA) for the above‐mentioned response variables yielded a high coefficient of determination (R2) value of 0.9985 and 0.9025 for the sorption capacity and sorption percentage, respectively. The desirability plot and overlay plot suggested the significance of the designed model. This is the first report on Cr6+sorption byM. racemosususing statistical experimental design employing RSM.
Statin medication use and the risk of biochemical recurrence after radical prostatectomy
Authors: Hamilton Robert J. , Banez Lionel L. , Aronson William J. , Terris Martha K. , Platz Elizabeth A. , Kane Christopher J. , Presti Joseph C. , Amling Christopher L. , Freedland Stephen J.
Published: June 2010

BACKGROUND:

Although controversial, evidence suggests statins may reduce the risk of advanced prostate cancer (PC), and recently statin use was associated with prostate‐specific antigen (PSA) reductions among men without PC. The authors sought to examine the association between statin use and PSA recurrence after radical prostatectomy (RP).

METHODS:

The authors examined 1319 men treated with RP from the Shared Equal Access Regional Cancer Hospital (SEARCH) Database. Time to PSA recurrence was compared between users and nonusers of statin at surgery using Cox proportional hazards models adjusted for multiple clinical and pathological features.

RESULTS:

In total, 236 (18%) men were taking statins at RP. Median follow‐up was 24 months for statin users and 38 for nonusers. Statin users were older (P< .001) and underwent RP more recently (P< .001). Statin users were diagnosed at lower clinical stages (P= .009) and with lower PSA levels (P= .04). However, statin users tended to have higher biopsy Gleason scores (P= .002). After adjusting for multiple clinical and pathological factors, statin use was associated with a 30% lower risk of PSA recurrence (hazard ratio “HR”, 0.70; 95% confidence interval “CI”, 0.50‐0.97;P= .03), which was dose dependent (relative to no statin use; dose equivalentsimvastatin 20 mg: HR, 0.50; 95% CI, 0.27‐0.93;P= .03).

CONCLUSIONS:

In this cohort of men undergoing RP, statin use was associated with a dose‐dependent reduction in the risk of biochemical recurrence. If confirmed in other studies, these findings suggest statins may slow PC progression after RP. Cancer 2010. © 2010 American Cancer Society.
SciScope: a participatory geoscientific web application
Authors: Beran Bora , van Ingen Catharine , Fatland Dennis Robert
Published: June 2010

The combination of low‐cost in situ sensors, internet connectivity, and commodity computing is changing earth science research. This unprecedented data availability is enabling science synthesis; studies that span disciplines, bridge local field, modeling and remote sensing methodologies and/or span local, regional, and global scales. Data discovery, retrieval, and heterogeneity act as cyberinfrastructure barriers to synthesis. Much of the available data is discovered by serendipity or word of mouth from independent, disconnected nodes with different interfaces and semantics. Before scientific analysis, data must be harmonized to a common understandable format. As the number of publishers increase, particularly when the publishers are small groups, this problem can only worsen. We have been developing SciScope (www.sciscope.org), a search tool that aggregates data set information and presents a simple map‐based interface across diverse data publishers. SciScope unites data catalog, semantic, structural and syntactic mediation, and Geographical Information Systems (GIS) functions. The current catalog contains 1.7 million observation sites from five different sources in the United States and Australia. SciScope encourages participatory science. Data consumers can find and retrieve data sets simply as well as annotate data sets. Data contributors can register and upload data sets as well as extend the semantic mediation to enable richer data searches. SciScopes can be federated to bridge between science communities that may not be willing or able to share a single catalog. Copyright © 2010 John Wiley & Sons, Ltd.
Finite difference schemes for heat conduction analysis in integrated circuit design and manufacturing
Authors: Shen Yijiang , Wong Ngai , Lam Edmund Y. , Koh Cheng‐Kok
Published: June 2010

The importance of thermal effects on the reliability and performance of VLSI circuits has grown in recent years. The heat conduction problem is commonly described as a second‐order partial differential equation (PDE), and several numerical methods, including simple explicit, simple implicit and Crank–Nicolson methods, all having at most second‐order spatial accuracy, have been applied to solve the problem. This paper reviews these methods and further proposes a fourth‐order spatial‐accurate finite difference scheme to better approximate the PDE solution. Moreover, we devise a fourth‐order accurate approximation of the convection boundary condition, and apply it to the proposed finite difference scheme. We use a block cyclic reduction and a recently developed numerically stable algorithm for inversion of block‐tridiagonal and banded matrices to solve the PDE‐based system efficiently. Despite their higher computation complexity than direct computation in a sequential processor, we make it possible for the very first time to employ a divide‐and‐conquer algorithm, viable for parallel computation, in heat conduction analysis. Experimental results prove such possibility, suggesting that applying divide‐and‐conquer algorithms, higher‐order finite difference schemes can achieve better simulation accuracy with even faster speed and less memory requirement than conventional methods. Copyright © 2010 John Wiley & Sons, Ltd.
Design of a two‐output forward converter with an output voltage objective function
Authors: Lo Yu‐Kang , Chen Jun‐Ting , Song Tze‐Herng , Ou Sheng‐Yuan
Published: June 2010

A new method is proposed in this paper to distribute the steady‐state output voltage errors in a two‐output forward converter. The cross regulation between the two output voltages are described in terms of the circuit parameters. An objective function is formed for each of the two outputs to track its reference within the specified error. The legitimate duty cycle range is located through the transfer characteristics between the duty cycle and the load currents. The weighting feedback gains of the two output voltages can be determined by the presented control scheme which optimizes the objective function. The proposed method is suitable for a two‐output system without a dominant load. Experiments on a prototype are conducted to show that there exist a duty cycle range and a set of weighted feedback gains minimizing the defined objective function. Copyright © 2010 John Wiley & Sons, Ltd.
An efficient traffic control system using dynamic thresholding techniques in wireless mesh networks
Authors: Lin P. J. , Dow C. R. , Hsuan P. , Hwang S. F.
Published: June 2010

Wireless mesh networks (WMNs) depend on a resilient and high‐performance infrastructure to provide users pervasive Internet access. In WMNs, all Internet traffic will be forwarded to the Internet gateways. Hence, these gateways are generally bottleneck nodes. This work proposes a traffic control technique to reduce the bottleneck problem and increase the utilization of network resources. Our approach provides a traffic control strategy that exploits dynamic techniques to adjust the threshold according to the traffic load of each gateway. The base threshold is defined in order to effectively control the traffic. When the current load exceeds the threshold of a gateway, the traffic redirection strategy is implemented by switching border nodes. The service regions can be adjusted for each gateway based on the traffic load. Furthermore, the proposed dynamic thresholding approaches can distribute the workloads of gateways and maintain the thresholds of any two gateways within a level range, making an in‐band balance of load. Thus, our proposed scheme can handle the unnecessary traffic redirection and reduce the traffic control overhead for various distributions of traffic. Experimental results demonstrate that our scheme outperforms other schemes in terms of packet delivery ratio and efficiency, especially in bursty traffic environments. Copyright © 2010 John Wiley & Sons, Ltd.
Mobilead hocnetwork broadcasting: A multi‐criteria approach
Authors: Barritt Brian J. , Sheikh Shaya , Al‐Najjar Camelia , Malakooti Behnam
Published: June 2010

Nodes in a computer network often require a copy of a message to be delivered to every node in the network. The network layer can provide such a service, referred to as network‐wide broadcast routing or simply ‘broadcasting’. Broadcasting has many applications, including its role as a service to many routing protocols. In a mobilead hocnetwork (MANET), simplistic broadcast schemes (such as flooding) inundate the network with redundancy, contention, collision, and unnecessary use of energy resources. This can prevent broadcasts from achieving their primary objective of maximizing delivery ratio, while also considering secondary objectives, such as balancing energy resources or reducing the network's burden on congested or busy nodes. As a solution, we propose multiple‐criteria broadcasting (MCB). In MCB, the source of each broadcast specifies the importance assigned to broadcast objectives. Network nodes use these priorities, along with local and neighbor knowledge of distributed factors, to broadcast in accordance with the objective priorities attributed to the message. Usingns2, the performance of MCB is evaluated and compared to that of other broadcast protocols. To present knowledge, MCB constitutes the first reconfigurable, multi‐objective approach to broadcasting. Copyright © 2010 John Wiley & Sons, Ltd.
Myocardial perfusion scintigraphy in asymptomatic diabetic patients: a critical review
Authors: Moralidis E. , Didangelos T. , Arsos G. , Athyros V. , Mikhailidis D. P.
Published: June 2010

The increasing prevalence of diabetes mellitus and the associated high cardiovascular risk has made the non‐invasive identification of silent coronary heart disease in diabetic individuals an important issue. This strategy could identify higher risk asymptomatic patients with diabetes mellitus in whom coronary revascularization may improve the outcome beyond that achieved by currently recommended medical management. Stress myocardial perfusion imaging has been shown to be effective in detecting coronary heart disease and predicting adverse cardiac events in asymptomatic diabetic patients. However, the clinical utility of myocardial perfusion scintigraphy is debated intensively due to the paucity of prospective and outcome based evidence. The controversy stems from several observational studies, epidemiologic data and cost‐effectiveness analyses. Thus, although several authors and professional organizations advocate the use of stress imaging for screening higher risk asymptomatic diabetic patients, others are cautious in recommending any kind of stress testing in that population. This review is based on a broad survey of the literature and discusses the potential role of stress myocardial perfusion scintigraphy in screening asymptomatic diabetic subjects for coronary heart disease in the current era and in relation with other non‐invasive screening tools. Copyright © 2010 John Wiley & Sons, Ltd.
The roles of NADPH‐oxidase and nNOS for the increased oxidative stress and the oxygen consumption in the diabetic kidney
Authors: Edlund Jenny , Fasching Angelica , Liss Per , Hansell Peter , Palm Fredrik
Published: June 2010

Background

Sustained hyperglycaemia induces increased renal oxygen consumption resulting in reduced oxygen availability in the diabetic kidney. We investigated the roles of the nicotinamide adenine dinucleotide phosphate (NADPH)‐oxidase and the neuronal nitric oxide synthase (nNOS) for the increased oxygen consumption in streptozotocin‐diabetic rats.

Methods

Oxygen consumption was measured in isolated proximal tubular cells (PTC) from streptozotocin‐induced diabetic rats (n = 7–9 per group) with and without chronic treatment with apocynin, a NADPH‐oxidase inhibitor, or S‐methyl‐L‐thiocitrulline (SMTC), a selective nNOS inhibitor, or a combination of the two and the results were compared to normoglycaemic controls (n = 10). Oxidative stress was estimated from thiobarbituric acid reactive substances and protein expression measured by Western blot.

Results

Proximal tubular cells from untreated diabetic rats had increased oxygen consumption compared to controls (40.6 ± 7.9 versus 10.9 ± 2.0 nmol/mg protein/min). All treatments reduced the diabetes‐induced increase in oxygen consumption (apocynin 10.5 ± 1.7, SMTC 19.7 ± 3.0 and apocynin + SMTC 21.6 ± 3.6 nmol/mg protein/min). Neither apocynin nor SMTC had any effect on the oxygen consumption in cells pre‐incubated with ouabain, an inhibitor of active electrolyte transport. Oxidative stress was elevated in the diabetic kidney and inhibited by all treatments. The increased oxygen consumption by diabetic proximal tubular cells correlated with increased protein expressions of p47phox and nNOS and the treatments prevented these increases.

Conclusions

Diabetes induces oxidative stress, which increases oxygen consumption in proximal tubular cells. Inhibition of either NADPH‐oxidase or nNOS prevented the increased oxygen consumption. The effect of blocking both these enzymes was less than additive suggesting overlapping pathways which warrant further studies. Copyright © 2010 John Wiley & Sons, Ltd.
Bismuth‐Coated Reticulated Vitreous Carbon and Bismuth‐Coated Glassy Carbon Electrodes for On‐Line Coupling of ASV with ICP‐MS
Authors: Liu Lin , Do Huy N. L. , Wang Jianxiu , Zhou Feimeng
Published: June 2010

Anodic stripping voltammetry (ASV) has been combined on‐line with inductively coupled plasma‐mass spectrometry (ICP‐MS) using both Bi‐coated reticulated vitreous carbon (RVC) and Bi‐coated glassy carbon (GC) disk electrodes. Because the same flow cell is used for the RVC and GC disk electrodes, the analytical performances between these two types of Bi‐coated electrodes can be accurately compared for their utilizations in the ASV‐ICP‐MS technique. Comparison of the performances includes signal enhancement, reproducibility, dynamic range, and hydrodynamic stability of the Bi coating. The results indicate that the signal enhancement produced by the Bi‐coated RVC electrode (in the flow‐through configuration) is greater, while the hydrodynamic stability of the Bi‐coated GC disk electrode is better. Both types of electrodes were found to be highly effective in eliminating the matrix effects that are detrimental to ICP‐MS analysis. For the purpose of metal preconcentration, Bi has similar properties to Hg (e.g., high hydrogen overpotential and ability to accumulate a range of analytes). However, the Bi film is more robust than the Hg film in a flow system and, unlike Hg2+, Bi3+ in the solution does not cause the memory effect (i.e., it does not adhere onto glass nebulizer and spray chamber of ICP over a long period of time). The nontoxicity of bismuth also makes it an environmentally friendly alternative to mercury for coupling ASV on‐line with ICP‐based techniques.
Suppression of Potential Oscillations in PEFCs by Using Anode Catalyst Prepared by Polygonal Barrel‐Sputtering Method
Authors: Inoue M. , Hirakawa K. , Umeda M. , Abe T.
Published: June 2010

In this study, we investigated the suppression of potential oscillations that occur while feeding H2 gas including a large amount of CO to polymer electrolyte fuel cells. A carbon‐supported Pt–Ru alloy (Pt–Ru/C) sample was prepared by the polygonal barrel‐sputtering method. Electrochemical measurement was conducted in 1 N H2SO4 electrolyte solution saturated with H2 gas including CO of 1,000 ppm. From the measurement, it was found that the prepared Pt–Ru/C sample showed higher CO tolerance than a commercially available sample, and therefore, potential oscillations in the case of the prepared sample occurred for slightly longer intervals. Additional samples were prepared by sputtering different amounts of Ru on the prepared Pt–Ru/C sample, and it was observed that the average interval of potential oscillations increased with the amount of Ru. This result suggests that in the case of the polygonal barrel‐sputtering method, Ru plays an important role in suppressing potential oscillations and influences the CO tolerance of Pt–Ru/C.
A Molecular Dynamics Study on the Oxygen Diffusion in Doped Fluorites: The Effect of the Dopant Distribution
Authors: Tarancón A. , Morata A. , Peiró F. , Dezanneau G.
Published: June 2010

The effect of the dopant distribution on the oxygen diffusion in doped fluorites typically used for solid oxide fuel cells electrolyte applications has been analysed by using molecular dynamics simulations. The oxygen mass transport in both yttria‐stabilized zirconia (YSZ) and gadolinia‐doped ceria has been studied and compared in the range of temperatures between 1,159 and 1,959 K. A new methodology based on the analysis of local environments is used to describe the diffusion process at an atomic scale. Preferred vacancy migration pathways, most suitable conduction models, energy landscapes and jump efficiency have been detailed for each material. Finally, a particular case of non‐random distribution of dopants in YSZ is presented in order to quantitatively evaluate the effect of the dopant pattern on the mass transport properties and the potential of the methodology developed here for understanding and foreseeing real configurations at the nanoscale.
Contribution of case‐mix classification to profiling hospital characteristics and productivity
Authors: Kuwabara Kazuaki , Matsuda Shinya , Fushimi Kiyohide , Ishikawa Koichi B. , Horiguchi Hiromasa , Hayashida Kenshi , Fujimori Kenji
Published: June 2010

Case‐mix classification has made it possible to analyze acute care delivery case volumes and resources. Data arising from observed differences have a role in planning health policy. Aggregated length of hospital stay (LOS) and total charges (TC) as measures of resource use were calculated from 34 case‐mix groups at 469 hospitals (1 721 274 eligible patients). The difference between mean resource use of all hospitals and the mean resource use of each hospital was subdivided into three components: amount of variation attributable to hospital practice behavior (efficiency); amount attributable to hospital case‐mix (complexity); and amount attributable to the interaction. Hospital characteristics were teaching status (academic or community), ownership, disease coverage, patients, and hospital volume. Multivariate analysis was employed to determine the impact of hospital characteristics on efficiency. Mean LOS and TC were greater for academic than community hospitals. Academic hospitals were least associated with LOS and TC efficiency. Low disease coverage was a predictor of TC efficiency while low patient volume was a predictor of unnecessarily long hospital stays. There was an inverse correlation between complexity and efficiency for both LOS and TC. Policy makers should acknowledge that differentiation of hospital function needs careful consideration when measuring efficiency. Copyright © 2010 John Wiley & Sons, Ltd.
Evaluation and integration of soil salinity and water data for improved land use of underproductive coastal area in Orissa
Authors: Das Madhumita , Sethi R. R. , Sahoo N.
Published: June 2010

Coastal agriculture in Orissa is predominantly rainfed and hence vulnerable owing to uncertain distribution of rainfall over time. Lack of irrigation support and salt stress affect crop growth and reduce yield as well. Good quality aquifer and low‐saline soil are available but vary spatially. Promoting potential use of spatially varied resources, precise assessment of soil and water quality at micro‐level is therefore imperative. In this study the soil salt stress, availability and quality of underground aquifers at different sites were evaluated in the neighbourhood area of Chilika, the largest brackish water lagoon of Asia. Integrating soil salinity, soil moisture content, aquifer availability and quality, various farming strategies specific to different sites were developed. These could trigger 1.59 to 2 times more production from its present level in that area. Where there is a diverse occurrence of resources, a precise estimation of those resources' potentials thus provides keys to develop cost‐effective options for improving production in an underproductive area. Copyright © 2010 John Wiley & Sons, Ltd.
Comparative study on the influence of subcutaneous administration of diphenyl and dicholesteroyl diselenides on sulphydryl proteins and antioxidant parameters in mice
Authors: Kade I. J. , Rocha J. B. T.
Published: June 2010

Although in vitro data from our previous studies show that the antioxidant effect and reactions of both diphenyl diselenide (DPDS) and dicholesteroyl diselenide (DCDS) towards thiol‐containing proteins differ considerably, the present study sought to evaluate the interaction of both organodiselenides with thiol‐containing proteins in vivo. Mice were injected subcutaneously with DPDS or DCDS previously dissolved in soya bean oil at doses of 0.5 mmol kg−1 body weight for four consecutive days. The activities of delta aminolevulinic acid dehydratase (ALA‐D), Na+/K+‐ATPase, and isoforms of lactate dehydrogenase (LDH) and catalase were investigated. In addition, the antioxidant status of the mice was determined by measuring the levels of glutathione (GSH), vitamin C (Vit C) and thiobarbituric acid reactive substances. The results show that both diselenides significantly increased the levels of GSH and Vit C but did not markedly alter other antioxidant indices. With respect to the thiol‐containing enzymes that were evaluated, DPDS and not DCDS caused a marked reduction in the activities of hepatic ALA‐D; however, both diselenides inhibited all isoforms of LDH evaluated. In addition, the activities of cerebral Na+/K+‐ATPase were not markedly inhibited by both diselenides, suggesting that this cerebral enzyme may not be a molecular target of organodiselenides toxicity. Taken together, the pharmacological and toxicological chemistry of organoselenium compounds is complex and multifactorial and is dependent on delicate equations which include vehicle solution, animal species and mode of delivery. Copyright © 2010 John Wiley & Sons, Ltd.
Skin sensitization, false positives and false negatives: experience with guinea pig assays
Authors: Basketter David A. , Kimber Ian
Published: June 2010

The advent of the local lymph node assay (LLNA), and efforts to develop in vitro alternatives for the identification of skin sensitizing chemicals has focused attention on the issue of false positive and false negative results. In essence, the question becomes ‘what is the gold standard?’ In this context, attention has focused primarily on the LLNA as this is now the preferred assay for skin sensitization testing. However, for many years prior to introduction of the LLNA, the guinea pig maximization test and the occluded patch test of Buehler were the methods of choice. In order to encourage a more informed dialogue about the relative performance, accuracy and applicability of the LLNA and guinea pig tests, we have here considered the extent to which guinea pig methods were themselves subject to false positives and negative results. We describe and discuss here well‐characterized examples of instances where both false negatives (including abietic acid and eugenol) or false positives (including vanillin and sulfanilic acid) have been recorded in guinea pig tests. These and other examples are discussed with particular reference to the fabrication of a gold standard dataset that is required for the validation of in vitro alternatives. Copyright © 2010 John Wiley & Sons, Ltd.
Ion channels in toxicology
Authors: Restrepo‐Angulo Iván , De Vizcaya‐Ruiz Andrea , Camacho Javier
Published: June 2010

Ion channels play essential roles in human physiology and toxicology. Cardiac contraction, neural transmission, temperature sensing, insulin release, regulation of apoptosis, cellular pH and oxidative stress, as well as detection of active compounds from chilli, are some of the processes in which ion channels have an important role. Regulation of ion channels by several chemicals including those found in air, water and soil represents an interesting potential link between environmental pollution and human diseases; for instance,de novoexpression of ion channels in response to exposure to carcinogens is being considered as a potential tool for cancer diagnosis and therapy. Non‐specific binding of several drugs to ion channels is responsible for a huge number of undesirable side‐effects, and testing guidelines for several drugs now require ion channel screening for pharmaceutical safety. Animal toxins targeting human ion channels have serious effects on the population and have also provided a remarkable tool to study the molecular structure and function of ion channels. In this review, we will summarize the participation of ion channels in biological processes extensively used in toxicological studies, including cardiac function, apoptosis and cell proliferation. Major findings on the adverse effects of drugs on ion channels as well as the regulation of these proteins by different chemicals, including some pesticides, are also reviewed. Association of ion channels and toxicology in several biological processes strongly suggests these proteins to be excellent candidates to follow the toxic effects of xenobiotics, and as potential early indicators of life‐threatening situations including chronic degenerative diseases. Copyright © 2010 John Wiley & Sons, Ltd.
A practical guide to multidimensional wave digital algorithms using an example of fluid dynamics
Authors: Hetmanczyk Georg , Ochs Karlheinz
Published: June 2010

The wave digital concept for numerical integration of partial differential equations leads to algorithms with highly advantageous features as robustness, full localness and massive parallelism. However, the required synthesis of an internally multidimensionally passive reference circuit, from which the algorithm is derived, usually demands an in‐depth knowledge of circuit theory and a high level of intuition. In this practical guide, a step‐by‐step approach for the synthesis of such reference circuits is introduced to relax these requirements, using the nonlinear fluid dynamic equations as a nontrivial example. General implementation issues for the wave digital algorithm are discussed as well as applying arbitrary passive linear multistep methods in place of the commonly used trapezoidal rule. As an example, we take the well‐known numerically critical shock tube problem, the solution of which is problematic when the trapezoidal rule is used as unwanted oscillations occur. These oscillations are suppressed when using the second‐order accurate Gear method instead. Copyright © 2010 John Wiley & Sons, Ltd.
Hyper‐production of α‐amylase from agro‐residual medium with high‐glucose in SSF using catabolite derepressed Bacillus subtilis KCC103
Authors: Rajagopalan Gobinath , Krishnan Chandraraj
Published: June 2010

In Bacillus subtilis KCC103, α‐amylase is hyper‐produced and α‐amylase synthesis is not subject to catabolite repression. The α‐amylase was produced from KCC103 by solid‐state fermentation (SSF) using agro‐residues and oil cakes as growth substrates. The KCC103 was also tested for its resistance to repression by hyper level (>10% w/w) of glucose and xylose on α‐amylase production in SSF. Among growth media containing various combinations of agro‐residues, the medium with wheat bran and sunflower oil cake supported highest enzyme production (20700 IU (g dry wt)–1). The α‐amylase production was enhanced (4.2 folds) by optimizing the growth substrate and the process parameters: the optimal conditions were wheat bran:sun flower oil cake ratio‐1:1 (w/w), substrate particle size‐500 μm, substrate to flask volume‐1:100 (w/v), initial substrate moisture content‐90% (v/w), inoculum size‐35%, initial medium pH‐7.0, growth temperature‐37 °C and cultivation time‐48 h. α‐Amylase production was further enhanced up to 1.7 folds when SSF was carried out using optimized medium supplemented with sugars or yeast extract (1% w/v) under optimized conditions. Supplementation of biomass sugars, glucose or xylose at 20% (w/w), did not repress the synthesis of α‐amylase showing the hyper‐tolerance of KCC103 to repression by simple sugars on α‐amylase production in SSF. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Characterization of an extracellular alkaline lipase from Pseudomonas mendocina M‐37
Authors: Dahiya Praveen , Arora Pooja , Chaudhury Ashok , Chand Subhash , Dilbaghi Neeraj
Published: June 2010

A strain of Pseudomonas mendocina producing extracellular lipase was isolated from soil. The bacterium accumulates lipase in culture fluid when grown aerobically at 30 °C for 24 h in a medium composed of olive oil (1%) as substrate. Pseudomonas mendocina lipase was optimally active at pH 9.0, temperature of 50 °C and was found to be stable between pH 7.0–11.0. The lipase was inhibited by detergents such as SDS and Tween‐80. The enzyme was stable in various organic solvents tested with maximum stability in chloroform followed by toluene and exhibited 1–3 regiospecificity for hydrolytic reaction. This lipase was capable of hydrolyzing a variety of lipidic substrates and is mainly active towards synthetic triglycerides and fatty acid esters that possess a butyryl group. Metal ions like Mg2+, Ca2+ and Na+ stimulated lipase activity, whereas, Cu2+, Mn2+ and Hg2+ ions caused inhibition. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Thermotolerance of germlings and mycelium of the insect‐pathogenic fungus Metarhizium spp. and mycelial recovery after heat stress
Authors: Rangel Drauzio E. N. , Fernandes Éverton K. K. , Dettenmaier Seth J. , Roberts Donald W.
Published: June 2010

The upper temperature limits for germination and growth were determined for Metarhizium acridum (ARSEF 324, 3341 and 3609), M. robertsii (ARSEF 2575), M. anisopliae (ARSEF 5749), and Aspergillus nidulans (ATCC 10074). Most of the Metarhizium species germinated well at 35 and 36 °C; however, compared to 28 °C, the growth was very slow (except ARSEF 5749 from Mexico, which germinated at 35 °C, but did not grow at 34 or 36 °C). Germination was severely impaired at 38 and 40 °C for all Metarhizium species. ARSEF 324 conidia were the most thermotolerant. Based on radial growth measurements, however, none of the M. anisopliae or M. robertsii isolates grew (produced visible colonies) during 10 days at 38 °C. All Metarhizium species kept at 38 and 40 °C for 10 days resumed growth when transferred to 28 °C, and they all sporulated. When the plates were held 10 days at 42 °C, however, only the two M. acridum isolates (ARSEF 324 and 3609) grew after returning to 28 °C, but with some delay. Conidia germinated at restrictive temperatures, but the growth was impaired or discontinued soon after germination. Nevertheless, when transferred to a permissive temperature, they produced colonies and new conidia. In contrast, the thermophilic A. nidulans germinated and grew well at 42 °C, and therefore was much more thermotolerant than any of the Metarhizium spp. isolates. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Mating‐type orthologous genes in the primarily homothallic Moniliophthora perniciosa, the causal agent of Witches' Broom Disease in cacao
Authors: Kües Ursula , Navarro‐González Mónica
Published: June 2010

The cacao‐pathogenic Moniliophthora perniciosa C‐biotype is a primarily homothallic Agaricomycete of which the genome has recently become available. Searching of the genome sequence with mating type proteins from other basidiomycetes detected one or possibly two potential genes for HD1 homeodomain transcription factors, 7 or possibly 8 genes for potential pheromone receptors and five genes for putative pheromone precursors. Apparently, the fungus possesses gene functions encoded in the tetrapolar basidiomycetes in the A and B mating loci, respectively. In the tetrapolar species, the A and B mating type genes govern formation of clamp cells at hyphal septa of the dikaryon and their fusion with sub‐apical cells as well as mushroom production. The C‐biotype forms fused clamp cells and also basidiocarps on mycelia germinated from basidiospores and their development might be controlled by the detected genes. It represents the first example of a primarily homothallic basidiomycete where A ‐ and B ‐mating‐type‐like genes were found. Various strategies are discussed as how self‐compatibility in presence of such genes can evolve. An A ‐mating‐type like gene for an HD2 homeodomain transcription factor is, however, not included in the available sequence representing estimated 69% coverage of the haploid genome but there are non‐mating genes for other homeodomain transcription factors of currently unknown function that are conserved in basidiomycetes and also various ascomycetes. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Bacteriophage analysis of staphylokinase‐negative Staphylococcus aureus strains isolated from people
Authors: Piechowicz Lidia , Galin’︁ski Janusz , Garbacz Katarzyna , Haras Krystyna
Published: June 2010

Staphylokinase is one of virulence factors produced by Staphylococcus aureus strains. Producing it is associated with the presence of prophage in a bacterial cell which carries the sak gene. In this study, we examined the ability to produce staphylokinase by 257 S. aureus strains isolated from the inpatient and the outpatients (carriers) and the fact whether there is a correlation between sensitivity to bacteriophages and the lack of producing staphylokinase by strains. The results of this study showed, that staphylokinase‐negative strains of S.aureus are widely common inpatients and among outpatients and their percentage does not usually exceed 20% of staphylococci. All staphylokinase‐negative S. aureus strains were negative for sak gene. The correlations between a type of clinical material and the frequency of occurrence of staphylokinase‐negative strains has not been stated. Typing with the use of the basic set of phages has shown that these strains do not constitute a homogenous group and they belong to different phage types. The same phage patterns occur both in staphylokinase‐negative strains and in staphylokinase‐positive strains, and the differences in phage types have the quantitative character. S.aureus not producing staphylokinase are more frequently common in the phage group II than other phage groups (p < 0.0001) and are typed mainly by 3C and 55 phages. Staphylokinase‐negative strains of S. aureus do not occur among the phage group II of strains sensitive to phage 71. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Raman polarization analysis of highly crystalline polyethylene fiber
Authors: Puppulin Leonardo , Takahashi Yasuhito , Zhu Wenliang , Pezzotti Giuseppe
Published: June 2010

The complex orientation dependence in space of Raman active vibrations in the orthorhombic structure of polyethylene (PE) is discussed in terms of Raman tensor elements as intrinsic physical parameters of the lattice. Building upon the symmetry assignment of these vibrational modes, we systematically studied, from both theoretical and experimental viewpoints, the changes of polarized intensity for the Ag and the B2g + B3g vibrational modes with respect to PE molecular orientation. After explicitly expanding the Raman selection rules associated with the Ag and the B2g + B3g modes, introducing them into general expressions of the orientation distribution function, and validating them by means of a least‐square fitting procedure on experimental data, we compare here two mesostructural models for a highly crystallized and self‐aligned PE fiber structure. Stereological arguments are shown concerning the arrangement of orthorhombic fibrils in such a sample that unfold the correct values of five independent Raman tensor elements for orthorhombic PE. Copyright © 2010 John Wiley & Sons, Ltd.
Advances in Raman mapping of works of art
Authors: Ropret Polonca , Miliani Costanza , Centeno Silvia A. , Tavzes Črtomir , Rosi Francesca
Published: June 2010

Raman mapping can provide molecular information to complement data derived from other analytical techniques in works of art and other objects of cultural significance. Raman mapping can be performed using a motorized microscope stage that moves a sample or an object point by point in two spatial directions. The method can be used both noninvasively in works of art that fit under a microscope objective and in microsamples when, for example, obtaining information on the samples' layering structure is necessary. This paper reports on the development of a Raman mapping approach based on a set of scanning mirrors that direct the laser beam in two spatial directions, vertically through the microscope head or through a horizontal exit on the Raman microspectrometer. The first configuration still has limitations in terms of the size of the work of art that can be analyzed, as it has to fit under the microscope objective, but considerably larger objects can be studied when using the scanning mirrors placed in the horizontal exit. In this paper, the advantages and limitations of these two Raman mapping approaches are compared and discussed on the basis of an example of a contemporary oil painting on canvas. Copyright © 2010 John Wiley & Sons, Ltd.
Are Mechanistic and Statistical QSAR Approaches Really Different? MLR Studies on 158 Cycloalkyl‐Pyranones
Authors: Bhhatarai Barun , Garg Rajni , Gramatica Paola
Published: June 2010

Two parallel approaches for quantitative structure‐activity relationships (QSAR) are predominant in literature, one guided by mechanistic methods (including read‐across) and another by the use of statistical methods. To bridge the gap between these two approaches and to verify their main differences, a comparative study of mechanistically relevant and statistically relevant QSAR models, developed on a case study of 158 cycloalkyl‐pyranones, biologically active on inhibition (Ki) of HIV protease, was performed. Firstly, Multiple Linear Regression (MLR) based models were developed starting from a limited amount of molecular descriptors which were widely proven to have mechanistic interpretation. Then robust and predictive MLR models were developed on the same set using two different statistical approaches unbiased of input descriptors. Development of models based on Statistical I method was guided by stepwise addition of descriptors while Genetic Algorithm based selection of descriptors was used for the Statistical II. Internal validation, the standard error of the estimate, and Fisher’s significance test were performed for both the statistical models. In addition, external validation was performed for Statistical II model, and Applicability Domain was verified as normally practiced in this approach. The relationships between the activity and the important descriptors selected in all the models were analyzed and compared. It is concluded that, despite the different type and number of input descriptors, and the applied descriptor selection tools or the algorithms used for developing the final model, the mechanistical and statistical approach are comparable to each other in terms of quality and also for mechanistic interpretability of modelling descriptors. Agreement can be observed between these two approaches and the better result could be a consensus prediction from both the models.
Pharmacophores in Drug Research
Authors: Langer Thierry
Published: June 2010

The pharmacophore concept in modern drug research is highlighted and the most important use examples and success stories are reviewed. These include papers from method development as well as from application areas. As indicated by the number of publications available, the pharmacophore approach has proven to be extremely useful as interface between medicinal and computational chemistry, both in virtual screening and library design for efficient hit discovery, but also in the optimization of lead compounds to clinical candidates. Recent studies focus on the usage of parallel screening using pharmacophore models for bio‐activity profiling and early stage risk assessment of potential side effects and toxicity due to interaction of drug candidates with anti‐targets.
Towards Proteome–Wide Interaction Models Using the Proteochemometrics Approach
Authors: Strömbergsson Helena , Lapins Maris , Kleywegt Gerard J. , Wikberg Jarl E. S.
Published: June 2010

A proteochemometrics model was induced from all interaction data in the BindingDB database, comprizing in all 7078 protein‐ligand complexes with representatives from all major drug target categories. Proteins were represented by alignment‐independent sequence descriptors holding information on properties such as hydrophobicity, charge, and secondary structure. Ligands were represented by commonly used QSAR descriptors. The inhibition constant (pKi) values of protein‐ligand complexes were discretized into “high” and “low” interaction activity. Different machine‐learning techniques were used to induce models relating protein and ligand properties to the interaction activity. The best was decision trees, which gave an accuracy of 80 % and an area under the ROC curve of 0.81. The tree pointed to the protein and ligand properties, which are relevant for the interaction. As the approach does neither require alignments nor knowledge of protein 3D structures virtually all available protein‐ligand interaction data could be utilized, thus opening a way to completely general interaction models that may span entire proteomes.
The role of endothelial nitric oxide synthase (eNOS) T‐786C, G894T, and 4a/b gene polymorphisms in the risk of idiopathic male infertility
Authors: Safarinejad Mohammad Reza , Shafiei Nayyer , Safarinejad Saba
Published: June 2010

A considerable number of infertile men have no known mechanism for their infertility. This study aims to examine if there is an association between endothelial nitric oxide synthase (eNOS) T‐786C, G894T, and 4a/b gene polymorphisms and idiopathic male infertility. Three hundred fifty‐two men with idiopathic infertility (mean age 32.4 ± 11.4 years) and 356 healthy controls (mean age 33.2 ± 11.6 years) with documented fertility were recruited in this study. Genotypes for T‐786C, G894T, and 4a/b gene polymorphisms were identified by the polymerase chain reaction–restriction fragment length polymorphism (PCR‐RFLP) analysis. The eNOS −786CC genotype (0.310 vs. 0.081; odds ratio (OR), 3.64; 95% confidence interval (CI), 2.28–4.46; P = 0.001), 894TT genotype (0.131 vs. 0.006; OR, 3.62; 95% CI, 2.68–4.87; P = 0.001) and 4aa genotype (0.128 vs. 0.009; OR, 2.82; 95% CI, 1.88–3.89; P = 0.004) were significantly more frequent in infertile subjects. Furthermore, there was a significant difference between the group of infertile patients with azoospermia and oligoasthenoteratozoospermia (OAT) when compared by genotype distribution (−786CC vs. 786TT, 894TT vs. 894GG, and 4aa vs. 4bb) (all P < 0.01). We also found an association between the eNOS “−786C,” “894T,” and “a” alleles and an increased risk of poor semen parameters. Our data revealed a significant relationship between eNOS genotypes and the phenotype of infertility. Mol. Reprod. Dev. 77: 720–727, 2010. © 2010 Wiley‐Liss, Inc.
Dynamic roles of ion currents in early development
Authors: Tosti Elisabetta
Published: June 2010

Excitable cells have the capacity to modify their electrical properties in response to different stimuli. This specific feature is due to a flux of ion currents that flow via ion channels in the plasma membrane. In all species so far studied, ion channels are proteins expressed in the zygote and in the blastomeres of the developing embryo, and their activity is subject to dynamic changes throughout the early cleavage stages. Although these complex patterns imply that ion currents play a role in signal transduction and the control of embryogenesis, a specific developmental function for the appearance, loss, and alterations of the channels remains to be elucidated. This review reports several aspects surrounding the involvement of ion currents in early embryo development, from invertebrates to human. It focuses on the occurrence, modulation, and dynamic role of ion fluxes through external, intra‐ and inter‐cellular ion channels from the zygote up to the blastula and pre‐implantation stages. The implications for a role of ion currents in development, and their possible clinical and technological applications are discussed. Mol. Reprod. Dev. 77:856–867, 2010. © 2010 Wiley‐Liss, Inc.