bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sibship analysis of associations between SNP haplotypes and a continuous trait with application to mammographic density
Authors: Stone J. , Gurrin L. C. , Hayes V. M. , Southey M. C. , Hopper J. L. , Byrnes G. B. 
Published: November 2009

AbstractHaplotype‐based association studies have been proposed as a powerful comprehensive approach to identify causal genetic variation underlying complex diseases. Data comparisons within families offer the additional advantage of dealing naturally with complex sources of noise, confounding and population stratification. Two problems encountered when investigating associations between haplotypes and a continuous trait using data from sibships are (i) the need to define within‐sibship comparisons for sibships of size greater than two and (ii) the difficulty of resolving the joint distribution of haplotype pairs within sibships in the absence of parental genotypes. We therefore propose first a method of orthogonal transformation of both outcomes and exposures that allow the decomposition of between‐ and within‐sibship regression effects when sibship size is greater than two. We conducted a simulation study, which confirmed analysis using all members of a sibship is statistically more powerful than methods based on cross‐sectional analysis or using subsets of sib‐pairs. Second, we propose a simple permutation approach to avoid errors of inference due to the within‐sibship correlation of any errors in haplotype assignment. These methods were applied to investigate the association between mammographic density (MD), a continuously distributed and heritable risk factor for breast cancer, and single nucleotide polymorphisms (SNPs) and haplotypes from the VDR gene using data from a study of 430 twins and sisters. We found evidence of association between MD and a 4‐SNP VDR haplotype. In conclusion, our proposed method retains the benefits of the between‐ and within‐pair analysis for pairs of siblings and can be implemented in standard software. Genet. Epidemiol. 34: 309–318, 2010.  © 2009 Wiley‐Liss, Inc.
Impacts of climate change on hydrological processes in the headwater catchment of the Tarim River basin, China
Authors: Liu Zhaofei , Xu Zongxue , Huang Junxiong , Charles Stephen P. , Fu Guobin 
Published: November 2009

AbstractThe impacts of climate change on hydrological processes in the headwater catchment of the Tarim River Basin (TRB), the largest inland river basin in China, were assessed using the variable infiltration capacity (VIC) macro‐scale hydrological model. The Delta method, a relatively simple and widely used method for constructing regional climate change scenarios for impact assessment, was used to project climate change scenarios based on GCM A2 and B2 scenarios. Projected meteorological variables for these two scenarios were inputted to the VIC model to simulate hydrological changes. The impacts of climate change on evapotranspiration and runoff in the catchment were assessed. Results showed that the runoff in winter exhibited a decreasing trend. As runoff in winter is mainly generated from snowmelt, this could have resulted from a decreasing trend in air temperature. Runoff in spring exhibited an increasing trend, which may be beneficial to agriculture. Overall, runoff in the study area showed a slight decreasing trend, while evapotranspiration exhibited an increasing trend. These results imply that water availability in the TRB is likely to become more critical in the future. Copyright © 2009 John Wiley & Sons, Ltd.
Variability in smallholders' irrigation water values: Study in North‐West Province, South Africa
Authors: Speelman S. , Frija A. , Perret S. , D'haese M. , Farolfi S. , D'haese L. 
Published: November 2009

AbstractCapturing the economic value of water use is an integral part in the design of economic incentives and institutional arrangements that can ensure sustainable, efficient and equitable allocation of water. Irrigation water values of small‐scale irrigators are, however, seldom studied and too little attention is paid to the determinants of the variability of water values. In South Africa issues like the call for more efficient water allocation resulting from growing water scarcity, the approaching introduction of water charges for smallholders and the crucial role in rural development attributed to small‐scale schemes, render this knowledge even more important. This study therefore first assesses irrigation water values at small‐scale irrigation schemes in South Africa using the residual imputation method. Results reveal that, without input subsidies, smallholders have difficulties generating a profit from certain irrigated crops. This raises doubts about the capacity of smallholders to pay for water. The average economic value of irrigation water in this study is US$0.188 m−3. The water values are, however, shown to be highly variable. The General Linear Model shows that this variability can be mainly attributed to the crop choice and to the irrigation scheme design and institutional setting. Copyright © 2009 John Wiley & Sons, Ltd.
Management of microfinance institutions: Do subsidies matter?
Authors: Hudon Marek 
Published: November 2009

AbstractIt is estimated that donors commit between US$ 800 million and US$ 1 billion to microfinance per year. This paper analyses the management of microfinance institutions (MFIs) and its relationship with donors' subsidies. The results show that the level of subsidies granted per year is related to the management quality but not the subsidies divided by the gross loan portfolio or the total equity. Well‐managed MFIs are larger and regulated organisations but not significantly older. The organisational structure or the experience of the MFI however does not play a role in determining its financial effectiveness, except for cooperatives. Copyright © 2009 John Wiley & Sons, Ltd.
Repair of large osteochondral defects in rabbits using porous hydroxyapatite/collagen (HAp/Col) and fibroblast growth factor‐2 (FGF‐2)
Authors: Maehara Hidetsugu , Sotome Shinichi , Yoshii Toshitaka , Torigoe Ichiro , Kawasaki Yuichi , Sugata Yumi , Yuasa Masato , Hirano Masahiro , Mochizuki Naomi , Kikuchi Masanori , Shinomiya Kenichi , Okawa Atsushi 
Published: November 2009

AbstractArticular cartilage has a limited capacity for self‐renewal. This article reports the development of a porous hydroxyapatite/collagen (HAp/Col) scaffold as a bone void filler and a vehicle for drug administration. The scaffold consists of HAp nanocrystals and type I atelocollagen. The purpose of this study was to investigate the efficacy of porous HAp/Col impregnated with FGF‐2 to repair large osteochondral defects in a rabbit model. Ninety‐six cylindrical osteochondral defects 5 mm in diameter and 5 mm in depth were created in the femoral trochlear groove of the right knee. Animals were assigned to one of four treatment groups: porous HAp/Col impregnated with 50 µl of FGF‐2 at a concentration of 10 or 100 µg/ml (FGF10 or FGF100 group); porous HAp/Col with 50 µl of PBS (HAp/Col group); and no implantation (defect group). The defect areas were examined grossly and histologically. Subchondral bone regeneration was quantified 3, 6, 12, and 24 weeks after surgery. Abundant bone formation was observed in the HAp/Col implanted groups as compared to the defect group. The FGF10 group displayed not only the most abundant bone regeneration but also the most satisfactory cartilage regeneration, with cartilage presenting a hyaline‐like appearance. These findings suggest that porous HAp/Col with FGF‐2 augments the cartilage repair process. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:677–686, 2010
A capital partnership: how human and venture capital affect the growth of high‐tech start‐ups
Authors: Colombo Massimo G. , Grilli Luca 
Published: November 2009

Abstract

Founders' human capital and venture capital (VC) are two fundamental ingredients for new venture success in high‐tech sectors. We jointly investigate their influence on the growth performance of a large sample of Italian high‐tech start‐ups and find:

the importance of both components;

some characteristics of founders' human capital also exert an indirect rather than a direct effect on growth by attracting VC;

the ‘coach’ function performed by Italian venture capitalists on invested companies is important;

a substitution rather than a complementary relationship exists between these two drivers of firm growth.

Copyright © 2009 John Wiley & Sons, Ltd.
What can venture capitalists and entrepreneurs learn from behavioral economists?
Authors: Yazdipour Rassoul 
Published: November 2009

Abstract

Building upon new findings from the field of behavioral finance and economics, this article provides fresh insights into how venture capitalists (VCs) and entrepreneurs perceive, experience, and deal with risk; and how they go about making decisions in their respective areas of venture creation, venture evaluation, venture growth, and investing.

By helping VCs and entrepreneurs to be cognizant of the many psychological traps that continuously get turned on at and around decision‐making times, such findings would certainly help both parties to avoid committing costly mistakes in their businesses.

Copyright © 2009 John Wiley & Sons, Ltd.
Business angels: who they really are
Authors: Ramadani Veland 
Published: November 2009

Abstract

Financing is a critical issue for the survival and development of small and medium‐sized enterprises. Business angels play a key role in financing these enterprises, especially innovative ones with high growth potential. Business angels fill the gap between founders, family, and friends on one side, and institutional venture capital funds on the other side, as a financing source. Business angels invest a large amount of money in seed, start‐up, and early‐stage enterprises.

Business angels are important for small and medium‐sized enterprises because they provide more than money. They are hands‐on investors and contribute their skills, expertise, knowledge, and contacts in the businesses they invest in. They are wealthy persons with great business experience, willing to invest and offer their wealth and knowledge to owners and to entrepreneurs to start or develop their businesses.

Business angels like to remain anonymous, so many ideas cannot be implemented. To address this issue, many countries establish business angel syndicates and networks to facilitate the process of matching entrepreneurs and business angels.

Copyright © 2009 John Wiley & Sons, Ltd.
Runoff, soil loss, and nutrient depletion under traditional and alternative cropping systems in the Transmexican Volcanic Belt, Central Mexico
Authors: Bravo‐Espinosa M. , Mendoza M. E. , Medina‐Orozco L. , Prat C. , García‐Oliva F. , López‐Granados E. 
Published: November 2009

AbstractIn the Transmexican Volcanic Belt a traditional fallow system is practiced, called “año y vez” (AV), which does not benefit soil conservation due to its low level of nutrient recycling and because soil protection is poor during the cultivation year. The objective of the present work was to measure runoff and soil and nutrient losses during three annual cycles (2002–2004) in Central Mexico under AV rotation and two alternative systems: improved traditional (IT) and traditional organic (TO). Soil losses in the three systems were moderate (<1.2 Mg ha−1 y−1) except during 2002, in which significant soil losses were recorded in IT and TO due to the scarcity of plant cover (<20 per cent) that was present throughout the rainy season. During the resting period of the AV system (2003), the annual runoff increased from 19 to about 600 per cent, compared to IT and TO without grazing. The difference in runoff was attributed to an 18 per cent increase in bulk density of soil surface (0–5 cm) caused by cattle trampling while grazing. Nutrient losses in the three treatments were mainly of N, Ca2+, Mg2+, Na+, and K+. These results suggest that AV has a higher topsoil degradation effect during the resting year than during the cultivation period. The study shows that incorporating the maize/beans‐black oat rotation and residue cover causes a low runoff response that is important in reducing soil degradation. A spatial analysis is presented of erosion at watershed level for two soil management systems assessed. Copyright © 2009 John Wiley & Sons, Ltd.
Pachymic acid inhibits cell growth and modulates arachidonic acid metabolism in nonsmall cell lung cancer A549 cells
Authors: Ling Hui , Jia Xiaobin , Zhang Yaochun , Gapter Leslie A. , Lim Yin‐shan , Agarwal Rajesh , Ng Ka‐yun 
Published: November 2009

AbstractAberrant arachidonic acid (AA) metabolism has been involved in inflammation and carcinogenesis. The key enzymes in AA metabolism such as cytosolic phospholipase A2 (cPLA2) and cyclooxygenase‐2 (COX‐2) have been implicated in the development and progression of many human cancers, including lung cancer. Hence, the blockade of these enzymes may suppress promotion and survival of human cancer cells. We and others have shown that a natural triterpenoid, pachymic acid (PA), can exhibit antiinflammatory and anticancer properties; however, its potential mechanism has not been fully clarified. In this study, we examined the effect of PA on the proliferation of human nonsmall cell lung cancer A549 cells. Furthermore, we investigated the influences of nontoxic levels of PA on AA metabolism. Additionally, the cellular events and signal transduction pathways influenced by PA were also examined. Our results showed that PA (1) inhibited anchorage‐dependent and ‐independent A549 growth in a concentration‐dependent manner, (2) induced apoptosis and disrupted mitochondrial membrane potential in A549 cells, and at nonlethal levels, (3) decreased IL‐1β‐induced activation of cPLA2 and COX‐2, (4) suppressed IL‐1β‐induced activation of mitogen‐activated protein kinases (MAPKs), and (5) inhibited IL‐1β‐stimulated nuclear factor kappa B (NF‐κB) signaling pathways. We speculate that inhibition of AA metabolism by PA is mediated in part by its inhibition of MAPKs and NF‐κB signaling pathways. Our study reveals that, apart from its cytotoxic effect, PA has the chemopreventive potential by reducing production of eicosanoids from AA metabolism. © 2009 Wiley‐Liss, Inc.
Navigator accuracy requirements for prospective motion correction
Authors: Maclaren Julian , Speck Oliver , Stucht Daniel , Schulze Peter , Hennig Jürgen , Zaitsev Maxim 
Published: November 2009

AbstractProspective motion correction in MRI is becoming increasingly popular to prevent the image artifacts that result from subject motion. Navigator information is used to update the position of the imaging volume before every spin excitation so that lines of acquired k‐space data are consistent. Errors in the navigator information, however, result in residual errors in each k‐space line. This paper presents an analysis linking noise in the tracking system to the power of the resulting image artifacts. An expression is formulated for the required navigator accuracy based on the properties of the imaged object and the desired resolution. Analytical results are compared with computer simulations and experimental data. Magn Reson Med, 2010. © 2009 Wiley‐Liss, Inc.
Improved signal to noise in proton spectroscopy of the human calf muscle at 7 T using localized B1 calibration
Authors: Versluis Maarten J. , Kan Hermien E. , van Buchem Mark A. , Webb Andrew G. 
Published: November 2009

AbstractLarge variations of tip angle within a slice can lead to suboptimal pulse power optimization using standard techniques, which measure the average tip angle over a slice; this effect is especially pronounced at fields of 7 T and above. A technique was introduced that performed a volume‐selective power optimization in less than 10 sec and automatically calibrates the radiofrequency pulses for subsequent spectroscopy scans. Using this technique, MR spectra were acquired in the human calf of seven healthy volunteers with a partial volume Tx/Rx coil. Increases in signal‐to‐noise ratio based upon the unsuppressed water signal between 22 ± 5% and 166 ± 42%, compared to spectra obtained with the conventional power calibration technique, were measured in different regions of the calf muscle. This new technique was able to measure the inhomogeneous radiofrequency field at 7 T and its use resulted in a considerable signal‐to‐noise ratio increase. Magn Reson Med, 2010. © 2009 Wiley‐Liss, Inc.
Multilevel ulnar neuropathy caused by multiple intraneural hemangiomas
Authors: Kim Dong Hwee , Kang Jong Woo , Park Jong Woong 
Published: November 2009

AbstractIntraneural hemangioma is extremely rare, and there are no reported cases that describe multilevel ulnar neuropathy caused by multiple intraneural hemangiomas in a single nerve. We report the case of a 47‐year‐old man with multilevel ulnar neuropathy caused by multiple intraneural hemangiomas in an ipsilateral ulnar nerve. Multilevel ulnar neuropathy was detected by electrodiagnosis, and intraneural hemangiomas were suggested by ultrasonographic evaluation before the operation. Careful surgical excision under an operating microscope ameliorated the patient's symptoms without recurrence. Muscle Nerve 41: 562–566, 2010
Flame retardancy and thermal degradation of intumescent flame retardant polypropylene material
Authors: Chen Xilei , Jiao Chuanmei 
Published: November 2009

AbstractThe flame retardancy and thermal degradation properties of polypropylene (PP) containing intumescent flame retardant additives, i.e. melamine pyrophosphate (MPyP) and charring‐foaming agent (CFA) were characterized by limiting oxygen index (LOI), UL 94, cone calorimeter, microscale combustion calorimetry, and thermogravimetric analysis (TGA). It has been found that the PP material containing only MPyP does not show good flame retardancy even at 30% additive level. Compared with the PP/MPyP binary system, the LOI values of the PP/MPyP/CFA ternary materials at the same additive loading are all increased, and UL 94 rating is raised to V‐0 from no rating (PP/MPyP). The cone calorimeter results show that the heat release rate and mass loss rate of some ternary materials decrease in comparison with the binary material. The microscale combustion calorimetry results indicate that the sample containing 22.5 wt% MPyP and 7.5 wt% CFA has the lowest heat release rate among all samples. The TGA results show that the thermal stability of the materials increases with the addition of MPyP, while decreases with the addition of CFA. Copyright © 2009 John Wiley & Sons, Ltd.
Massively regulated genes: the example of TP53
Authors: Hollstein Monica , Hainaut Pierre 
Published: November 2009

AbstractIntensive study of the TP53 gene over the last three decades has revealed a highly complex network of factors that regulate its performance. The gene has several promoters, alternative splicing occurs and there are alternative translation initiation sites. Up to 10 p53 isoforms have been identified. At the post‐translational level, p53 activity depends on its quantity in the cell and on qualitative changes in its structure, intracellular localization, DNA‐binding activity and interactions with other proteins. Both accumulation and activation are regulated by an intricate pattern of post‐translational modifications, including phosphorylation, acetylation, ubiquitination, sumoylation, neddylation, methylation and glycosylation. The Mdm2 protein, a negative regulator of p53, is the most important determinant of p53 abundance and subcellular localization. Enzymes that post‐translationally modify p53 by phosphorylation, methylation and acetylation fine‐tune p53 binding to recognition sequences in DNA and p53 interactions with transcription cofactors at promoters of target genes, thereby exerting a discriminatory role in p53 function. This multitude of parameters determining expression, modification, accumulation and localization of p53 proteins may explain how a single gene can display an extensive repertoire of activities. Presumably this is needed, because the p53 protein can have such profound consequences for a cell. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Substituent effect on local aromaticity in mono and di‐substituted heterocyclic analogs of naphthalene
Authors: Mohajeri Afshan , Shahamirian Mozhgan 
Published: November 2009

AbstractA quantitative study on local aromaticity has been performed on a series of mono‐ and di‐substituted biheterocycles (quinoline, isoquinoline, quinoxaline, quinazoline). Three electronically based indices (PDI, ATI, and FLU) have been employed to investigate the substituent effect on theπ‐electron delocalization in both heterocycle and benzenoid rings. Three typical substituents (Cl, OCH3, and CN) with different inductive and resonance power have been selected. Generally, substituent causes a reduction in aromaticity irrespective of whether it is electron attracting or electron donating. It is shown that the maximum aromaticity exhibits a similar trend of Cl > CN > OCH3for all the studied rings. Moreover, it is found that the substituent situation with respect to the heteroatom has a significant influence on the aromaticity. It results from our study that in di‐substituted derivatives, irrespective of whether the two substituents form a meta or para isomer, they preferably choose the position which leads to the maximum aromaticity character. Copyright © 2009 John Wiley & Sons, Ltd.
Primary kinetic hydrogen isotope effects in deprotonations of a nitroalkane by intramolecular phenolate groups
Authors: Backstrom Nicholas , Burton Neil A. , Watt C. Ian F. 
Published: November 2009

AbstractRate constants and kinetic isotope effects have been determined for the formation of nitronate anions from the ethers 1‐(2‐methoxyphenyl)‐2‐nitropropane, 7(X = H, L = H and D) and 1‐(2‐methoxy‐5‐nitrophenyl)‐2‐nitropropane, 7(X = NO2, L = H and D), and from the corresponding phenols, 1‐(2‐hydroxyphenyl)‐2‐nitropropane, 3(X = H, L = H and D), and 1‐(2‐hydroxy‐5‐nitrophenyl)‐2‐nitropropane, 3(X = NO2, L = H and D), in aqueous basic medium. For the ethers 7, rates of deprotonation by hydroxide are comparable with those found for deprotonations of 2‐nitropropane, with kH/kD (25 °C) = 7.7 and 7.8, respectively. In both the cases, the isotope effects are conventionally temperature dependent. For the corresponding phenols 3, conditions have been established under which the deprotonations of the nitroalkane are dominated by intramolecular deprotonation by the kinetically first‐formed phenolate anion, with an estimated effective molarity EM ∼ 250. For 3 (X = H, L = H or D), kH/kD (25 °C) = 7.8, with E − E = 6.9 kJ mol−1 and AH/AD = 0.5. For 3(X = NO2, L = H or D), rates of intramolecular deprotonation are reduced 30‐fold, and an elevated kinetic isotope effect is found (kH/kD (25 °C) = 10.7). Activation parameters (E − E = 17.8 kJ mol−1 and AH/AD = 0.008) are compatible with an enhanced tunnelling contribution to reactivity in the H‐isotopomer. Copyright © 2009 John Wiley & Sons, Ltd.