bluuebunny/crossref_metadata_2025_split huggingface dataset:
Catchment‐level evaluation of farmers' estimates of soil erosion and crop yield in the Central Highlands of Kenya
Authors: Okoba B.O. , Sterk G. 
Published: June 2010

AbstractSoil and water conservation programmes in Kenya were not always successful due to experts' negligence of the role of farmers in problem identification and conservation planning. Using farmers' knowledge of soil surface morphology to assess soil productivity may stimulate farmers to participate in solving the prevailing problems. The objective of this study was to compare farmers' soil erosion and crop yield estimations with a conventional science approach in a small (∼550 ha) catchment in the Central Highlands of Kenya. Farmers' knowledge and perceptions of the effect of topsoil erosion features was used to assess the soil erosion status across the catchment area. The conventional scientific approach used a survey methodology and GIS‐based up‐scaling to quantify soil erosion patterns. In addition, the farmers made qualitative estimations of crop yield losses, which were verified through actual crop yield measurements. The soil erosion pattern between the farmers and conventional science approaches showed a strong agreement at the hillslope scale, while at the catchment scale the agreement was slightly weaker. Farmers observed more area under nearly flat and gentle slopes to have high erosion than the area approximated by the conventional science approach. Farmers' prediction of crop yields loss in each erosion class showed no difference with the actual field measurements. Despite use of farmers' mapping of erosion pattern being participatory, thereby stimulating awareness creation on land degradation processes, it can be labour intensive and a slower approach than the conventional science approach in evaluating catchment‐scale erosion patterns. Copyright © 2010 John Wiley & Sons, Ltd.
AnL∞–Lpmesh‐adaptive method for computing unsteady bi‐fluid flows
Authors: Guégan D. , Allain O. , Dervieux A. , Alauzet F. 
Published: June 2010

AbstractThis paper discusses the contribution of mesh adaptation to high‐order convergence of unsteady multi‐fluid flow simulations on complex geometries. The mesh adaptation relies on a metric‐based method controlling theLp‐norm of the interpolation error and on a mesh generation algorithm based on an anisotropic Delaunay kernel. The mesh‐adaptive time advancing is achieved, thanks to a transient fixed‐point algorithm to predict the solution evolution coupled with a metric intersection in the time procedure. In the time direction, we enforce the equidistribution of the error, i.e. the error minimization inL∞norm. This adaptive approach is applied to an incompressible Navier–Stokes model combined with a level set formulation discretized on triangular and tetrahedral meshes. Applications to interface flows under gravity are performed to evaluate the performance of this method for this class of discontinuous flows. Copyright © 2010 John Wiley & Sons, Ltd.
Computing the NMR spectra of the sponge metabolite arsenicin A: when simple becomes difficult
Authors: Bagno Alessandro 
Published: June 2010

AbstractDetermining the structure of the natural polyarsenical arsenicin A has proved difficult, but computational chemistry has played a decisive role in the process. This paper aims at tracing the winding path that, in time, led to the correct structure. Copyright © 2010 John Wiley & Sons, Ltd.
Stability of benzoporphyrin photosensitizers in water/ethanol mixtures: pKadetermination and self‐aggregation processes
Authors: Tessaro André Luiz , Batistela Vagner Roberto , Gracetto Augusto César , Moisés de Oliveira Hueder Paulo , Sernaglia Rosana Lazara , de Souza Vagner Roberto , Caetano Wilker , Hioka Noboru 
Published: June 2010

AbstractBenzoporphyrin monoacid derivatives, here named B3A and B3B, are promising new drugs for photodynamic therapy. Although both isomers show interesting characteristics as photosensitizing compounds, they have some distinct physicochemical properties such as the tendency to self‐aggregate in water‐rich media. Because pH drives the presence of each species, the pKaof these compounds assumes strategic importance. However, traditional micro‐titration methods and UV–Vis absorption techniques fail to give reliable pKavalues due to the characteristics of this highly complex system, such as the precipitation of hydrophobic species, close pKavalues, and high absorption band superposition. In the present work, chemometric tools are employed to evaluate pKa, and the kinetic tendency of monomers to undergo self‐aggregation is investigated. In solvent mixtures at low water percentage in ethanol, both B3A and B3B are stabilized in a monomeric state. However, in mixtures with a high water content, self‐aggregation takes place, mainly under a mild pH acid condition (3 < pH < 6), in which the prevalent protolytic species of both isomers is the neutral charged form, compounds with carboxylic and porphyrin free‐base groups. It is demonstrated that both isomers can undergo aggregation following a self‐catalytic mechanism, which is 2000 times slower to B3A than B3B. For B3A, the aggregation is manifested by a decrease in the monomer band with the aggregation band probably superposed to that of the monomer. For B3B, together with the decrease in the monomer band, a new band related to self‐aggregates is observed. Copyright © 2010 John Wiley & Sons, Ltd.
Protein denaturation and protein:drugs interactions from intrinsic protein fluorescence measurements at the nanolitre scale
Authors: Matthieu Gaudet , Nina Remtulla , Sophie E. Jackson , Ewan R. G. Main , Daniel G. Bracewell , Gabriel Aeppli , Paul A. Dalby 
Published: June 2010

AbstractProtein stability and ligand‐binding affinity measurements are widely required for the formulation of biopharmaceutical proteins, protein engineering and drug screening within life science research. Current techniques either consume too much of often precious biological or compound materials, in large sample volumes, or alternatively require chemical labeling with fluorescent tags to achieve measurements at submicrolitre volumes with less sample. Here we present a quantitative and accurate method for the determination of protein stability and the affinity for small molecules, at only 1.5–20 nL optical sample volumes without the need for fluorescent labeling, and that takes advantage of the intrinsic tryptophan fluorescence of most proteins. Coupled to appropriate microfluidic sample preparation methods, the sample requirements could thus be reduced 85,000‐fold to just 108 molecules. The stability of wild‐type FKBP‐12 and a destabilizing binding‐pocket mutant are studied in the presence and absence of rapamycin, to demonstrate the potential of the technique to both drug screening and protein engineering. The results show that 75% of the interaction energy between FKBP‐12 and rapamycin originates from residue Phe99 in the binding site.
Increased aggregation propensity of IgG2 subclass over IgG1: Role of conformational changes and covalent character in isolated aggregates
Authors: Franey Heather , Brych Stephen R. , Kolvenbach Carl G. , Rajan Rahul S. 
Published: June 2010

AbstractAggregation of human therapeutic antibodies represents a significant hurdle to product development. In a test across multiple antibodies, it was observed that IgG1 antibodies aggregated less, on average, than IgG2 antibodies under physiological pH and mildly elevated temperature. This phenomenon was also observed for IgG1 and IgG2 subclasses of anti‐streptavidin, which shared 95% sequence identity but varied in interchain disulfide connectivity. To investigate the structural and covalent changes associated with greater aggregation in IgG2 subclasses, soluble aggregates from the two forms of anti‐streptavidin were isolated and characterized. Sedimentation velocity analytical ultracentrifugation (SV‐AUC) measurements confirmed that the aggregates were present in solution, and revealed that the IgG1 aggregate was composed of a predominant species, whereas the IgG2 aggregate was heterogeneous. Tertiary structural changes accompanied antibody aggregation as evidenced by greater ANS (8‐Anilino‐1‐naphthalene sulfonic acid) binding to the aggregates over monomer, and differences in disulfide character and tryptophan environments between monomer, oligomer and aggregate species, as observed by near‐UV circular dichroism (CD). Differences between subclasses were observed in the secondary structural changes that accompanied aggregation, particularly in the intermolecular β‐sheet and turn structures between the monomer and aggregate species. Free thiol determination showed ∼2.4‐fold lower quantity of free cysteines in the IgG1 subclass, consistent with the 2.4‐fold reduction in aggregation of the IgG1 form when compared with IgG2 under these conditions. These observations suggested an important role for disulfide bond formation, as well as secondary and tertiary structural transitions, during antibody aggregation. Such degradations may be minimized using appropriate formulation conditions.
Human and climate impacts on Columbia River hydrology and salmonids
Authors: Naik P. K. , Jay D. A. 
Published: June 2010

AbstractThe Columbia River had until recently the world's largest Chinook salmon runs. Restoration of the system's severely decimated runs requires understanding changes in the hydrologic variables (e.g. flow and sediment transport) important to salmonids. We describe here methods to distinguish the human and climate‐induced contributions to Columbia River hydrologic processes relevant to the crucial seaward spring migration of juveniles through the tidal river and estuary. Flow regulation has caused most of the decrease in peak flow and sediment transport; it has contributed to changes in spring freshet timing. Climate change has reduced peak and average flows and sediment transport, changing spring‐freshet timing by several weeks. Irrigation diversion has reduced the annual average flow as much as climate change. A better understanding of historical changes in hydrologic processes entailed in this paper tells us how management and climate have changed the Columbia River system over time. The separation of the climate and anthropogenic influences used here may assist in policy analyses and strategies aimed at restoration of the Columbia River endangered salmonids, and in management of other systems. Copyright © 2010 John Wiley & Sons, Ltd.
Spiky globalization of venture capital investments: the influence of prior human networks
Authors: Iriyama Akie , Li Yong , Madhavan Ravi 
Published: June 2010

AbstractWe demonstrate a spiky globalization pattern in the cross‐border spread of venture capital: rather than being uniformly distributed, cross‐border venture capital flows are unevenly distributed, in that certain regions of the U.S. display particularly intense linkages with certain foreign nations. We posit that such spiky globalization of venture capital is driven by the spiky globalization pattern of prior human networks between locations, and we provide empirical results supportive of our hypothesis. Specifically, we reason that immigrant entrepreneurs inherently tend to collocate with each other in their host nation, thus advantaging certain regions in the competition to act as sources and destinations of cross‐border venture capital. This study sheds new light on geographical patterns in international venture capital and entrepreneurship. Copyright © 2010 Strategic Management Society.
Learning from experience and learning from others: how congenital and interorganizational learning substitute for experiential learning in young firm internationalization
Authors: Bruneel Johan , Yli‐Renko Helena , Clarysse Bart 
Published: June 2010

AbstractThis article addresses a critical issue for entrepreneurs and managers pursuing internationalization strategies: how firms can accumulate the knowledge and skills required for successful international expansion. Specifically, we examine how young firms may compensate for their lack of firm‐level international experience by utilizing other sources of knowledge. Drawing on organizational learning theory, we develop an integrative framework that looks at the joint and interactive effects of experiential learning by the firm, the management team's pre‐start‐up international experience (i.e., congenital learning), and interorganizational learning from key exchange partners (customers, suppliers, investors, etc.). Utilizing empirical data on 114 young, technology‐based firms in Flanders, Belgium, we find that a firm's level of international experience negatively moderates the effects of congenital and interorganizational learning on the extent of internationalization. That is, the lower a firm's experiential learning, the more significant the effects of the start‐up team's prior international knowledge base and the knowledge and skills acquired through key partners. These results make important theoretical and empirical contributions to the international entrepreneurship and organizational learning literatures by highlighting some of the factors underlying learning advantages of newness that facilitate the internationalization of young firms and by explicating substitutive interrelationships among different learning mechanisms. Copyright © 2010 Strategic Management Society.
A multiple imputation approach to disclosure limitation for high‐age individuals in longitudinal studies
Authors: An Di , Little Roderick J. A. , McNally James W. 
Published: June 2010

AbstractDisclosure limitation is an important consideration in the release of public use data sets. It is particularly challenging for longitudinal data sets, since information about an individual accumulates with repeated measures over time. Research on disclosure limitation methods for longitudinal data has been very limited. We consider here problems created by high ages in cohort studies. Because of the risk of disclosure, ages of very old respondents can often not be released; in particular, this is a specific stipulation of the Health Insurance Portability and Accountability Act (HIPAA) for the release of health data for individuals. Top‐coding of individuals beyond a certain age is a standard way of dealing with this issue, and it may be adequate for cross‐sectional data, when a modest number of cases are affected. However, this approach leads to serious loss of information in longitudinal studies when individuals have been followed for many years. We propose and evaluate an alternative to top‐coding for this situation based on multiple imputation (MI). This MI method is applied to a survival analysis of simulated data, and data from the Charleston Heart Study (CHS), and is shown to work well in preserving the relationship between hazard and covariates. Copyright © 2010 John Wiley & Sons, Ltd.
Latent class joint model of ovarian function suppression and DFS for premenopausal breast cancer patients
Authors: Zhang Jenny J. , Wang Molin 
Published: June 2010

AbstractBreast cancer is the leading cancer in women of reproductive age; more than a quarter of women diagnosed with breast cancer in the US are premenopausal. A common adjuvant treatment for this patient population is chemotherapy, which has been shown to cause premature menopause and infertility with serious consequences to quality of life. Luteinizing‐hormone‐releasing hormone (LHRH) agonists, which inducetemporaryovarian function suppression (OFS), has been shown to be a useful alternative to chemotherapy in the adjuvant setting for estrogen‐receptor‐positive breast cancer patients. LHRH agonists have the potential to preserve fertility after treatment, thus, reducing the negative effects on a patient's reproductive health. However, little is known about the association between a patient's underlying degree of OFS and disease‐free survival (DFS) after receiving LHRH agonists. Specifically, we are interested in whether patients with lower underlying degrees of OFS (i.e. higher estrogen production)aftertaking LHRH agonists are at a higher risk for late breast cancer events. In this paper, we propose a latent class joint model (LCJM) to analyze a data set from International Breast Cancer Study Group (IBCSG) Trial VIII to investigate the association between OFS and DFS. Analysis of this data set is challenging due to the fact that the main outcome of interest, OFS, is unobservable and the available surrogates for this latent variable involve masked event and cured proportions. We employ a likelihood approach and the EM algorithm to obtain parameter estimates and present results from the IBCSG data analysis. Copyright © 2010 John Wiley & Sons, Ltd.
Response‐adaptive randomization for clinical trials with adjustment for covariate imbalance
Authors: Ning Jing , Huang Xuelin 
Published: June 2010

AbstractIn clinical trials with a small sample size, the characteristics (covariates) of patients assigned to different treatment arms may not be well balanced. This may lead to an inflated type I error rate. This problem can be more severe in trials that use response‐adaptive randomization rather than equal randomization because the former may result in smaller sample sizes for some treatment arms. We have developed a patient allocation scheme for trials with binary outcomes to adjust the covariate imbalance during response‐adaptive randomization. We used simulation studies to evaluate the performance of the proposed design. The proposed design keeps the important advantage of a standard response‐adaptive design, that is to assign more patients to the better treatment arms, and thus it is ethically appealing. On the other hand, the proposed design improves over the standard response‐adaptive design by controlling covariate imbalance between treatment arms, maintaining the nominal type I error rate, and offering greater power. Copyright © 2010 John Wiley & Sons, Ltd.
Endoscopic Thyroidectomy via Breast Approach for Patients with Graves’ Disease
Authors: Li Zhi Yu , Wang Ping , Wang Yong , Xu Shao Ming , Cao Li Ping , Que Ri Shen 
Published: June 2010

AbstractBackgroundEndoscopic thyroidectomy via breast approach provides excellent results from a cosmetic viewpoint. We applied this procedure to Graves’ disease and evaluated its feasibility and outcomes.MethodsFrom May 2006 to November 2009, a total of 37 patients (34 women and 3 men) with Graves’ disease were included in this study. Bilateral subtotal thyroidectomy, which left behind 4–6 g of thyroid remnant, was the standard procedure. For markedly enlarged goiter, fractional resection was performed.ResultsThis procedure was performed successfully in all 37 patients. The mean operative time, mean blood loss, and mean excised thyroid weight were 84.7 min, 64 ml, and 51.8 g, respectively. Fractional resection was performed in six cases, where the mean operative time, mean blood loss, and mean excised thyroid weight were 119 min, 138.3 ml, and 102.2 g, respectively. Postoperative transient hypocalcemia occurred in 5 cases (13.5%), and no other complications were noted. The average postoperative hospital stay was 3.4 (range, 3–5) days. One case experienced recurrent hyperthyroidism during a mean follow‐up period of 13 months. All patients were satisfied with the cosmetic result of the procedure.ConclusionsEndoscopic subtotal thyroidectomy performed via breast approach is a technically feasible and safe procedure with excellent cosmetic results for patients with Graves’ disease. In patients with markedly enlarged thyroid glands, subtotal thyroidectomy can be achieved through a fractional resection strategy.
Current concepts of human azoospermia and its causes
Authors: Miyamoto Toshinobu , Tsujimura Akira , Miyagawa Yasushi , Koh Eitetsu , Sato Hisashi , Namiki Mikio , Sengoku Kazuo 
Published: June 2010

AbstractInfertility is a serious social problem in advanced nations today. One of the most important causes is the male factor. Striking progress has been achieved in recent years in elucidating the mechanisms of spermatogenesis in mice by experimental methods represented by the knockout mouse. Although many factors associated with male infertility are known in mice, the translation of this information to people has been slow. This is because the knockout mouse phenotype cannot necessarily be reproduced faithfully in humans. However, it is known that environmental factors, chromosomal defects and several specific gene mutations result in human male infertility. In this review, we first discuss the environmental factors considered likely to be involved in male infertility, and secondly we describe the Y chromosome and several important genes on the Y chromosome that play critical roles in spermatogenesis in humans. Then, we demonstrate the three critical genes identified in our laboratory in autosomes involved in human spermatogenesis, the SYCP3, MEI1 and PARP‐2. Finally, we explain the future directionality and possibilities of research in this field.
Social identity change: Shifts in social identity during adolescence
Authors: Tanti Chris , Stukas Arthur A. , Halloran Michael J. , Foddy Margaret 
Published: June 2010

ABSTRACTThis study investigated the proposition that adolescence involves significant shifts in social identity as a function of changes in social context and cognitive style. Using an experimental design, we primed either peer or gender identity with a sample of 380 early‐ (12–13 years), mid‐ (15–16 years), and late‐adolescents (18–20 years) and then measured the effect of the prime on self‐stereotyping and ingroup favouritism. The findings showed significant differences in social identity across adolescent groups, in that social identity effects were relatively strong in early‐ and late‐adolescents, particularly when peer group identity rather than gender identity was salient. While these effects were consistent with the experience of change in educational social context, differences in cognitive style were only weakly related to ingroup favouritism. The implications of the findings for theory and future research on social identity during adolescence are discussed.
Inpatient mother-and-child postpartum psychiatric care: Factors associated with improvement in maternal mental health
Authors: Glangeaud-Freudenthal N.M.-C. , Sutter A.-L. , Thieulin A.-C. , Dagens-Lafont V. , Zimmermann M.-A. , Debourg A. , Massari B. , Cazas O. , Cammas R. , Rainelli C. , Poinso F. , Maron M. , Nezelof S. , Ancel P.-Y. , Khoshnood B. 
Published: June 2010

AbstractPurposeThis study assessed the underexplored factors associated with significant improvement in mothers’ mental health during postpartum inpatient psychiatric care.MethodsThis study analyzed clinical improvement in a prospective cohort of 869 women jointly admitted with their infant to 13 psychiatric Mother-Baby Units (MBUs) in France between 2001 and 2007. Predictive variables tested were: maternal mental illness (ICD-10), sociodemographic characteristics, mental illness and childhood abuse history, acute or chronic disorder, pregnancy and birth data, characteristics and mental health of the mother's partner, and MBU characteristics.ResultsTwo thirds of the women improved significantly by discharge. Admission for 25% was for a first acute episode very early after childbirth. Independent factors associated with marked improvement at discharge were bipolar or depressive disorder, a first acute episode or relapse of such an episode. Schizophrenia, a personality disorder, and poor social integration (as measured by occupational status) were all related to poor clinical outcomes.DiscussionMost women improved significantly while under care in MBUs. Our results emphasize the importance of the type of disease but also its chronicity and the social integration when providing postpartum psychiatric care.