bluuebunny/crossref_metadata_2025 huggingface dataset:
Array Comparative Genomic Hybridization Findings in a Cohort Referred for an Autism Evaluation
Authors: Schaefer G. Bradley , Starr Lois , Pickering Dianne , Skar Gwenn , DeHaai Kristi , Sanger Warren G.
Published: August 2010

The development and refinement of array comparative genomic hybridization has led to expanded applications as a diagnostic tool. Recent reports suggest a high diagnostic yield for array comparative genomic hybridization in autism spectrum disorders. The objective of this study was to determine the diagnostic yield in array comparative genomic hybridization for autism at the University of Nebraska Medical Center. The authors report the diagnostic yield of array comparative genomic hybridization in 89 samples with a primary indication of autism. Clinical information was reviewed for 89 identified cases. Twenty-one cases were excluded because of ambiguous information regarding the diagnosis, a diagnosis other than autism, or abnormal karyotype. Of 68 cases referred for array comparative genomic hybridization testing with a primary indication of autism, 14 (21%) had abnormal findings. This study supports array comparative genomic hybridization in the etiologic evaluation of autism and elevation of array to a first tier diagnostic test.
Why should I read histories of science?
Authors: Erickson Mark
Published: August 2010

History of science is, we are told, an important subject for study. Its rise in recent years to become a ‘stand alone’ discipline has been mirrored by an expansion of popular history of science texts available in bookstores. Given this, it is perhaps surprising that little attention has been given to how history of science is written. This article attempts to do that through constructing a typology of histories of science based upon a consideration of audiences who read these texts and writers who construct them. It identifies four ideal types of history of science which describe the opposite poles of two continua running from exoteric to esoteric. The article also examines the content of a sample of history of science texts and finds that often these texts, whether esoteric or exoteric, provide only a chronology of events (often incredibly detailed), avoiding discussion or even mention of wider social, economic and political contexts. Such histories serve to reinforce a ‘standard’ account of science as ‘separate’ from the rest of society, an account that is at odds with almost all contemporary sociology of science and science and technology studies. This prompts the question: why should I read histories of science?
Climate variability over the last two millennia in the North American Monsoon region, recorded in laminated lake sediments from Laguna de Juanacatlán, Mexico
Authors: Metcalfe S.E. , Jones M.D. , Davies S.J. , Noren A. , MacKenzie A.
Published: August 2010

High-resolution titanium (Ti) data obtained using an ITRAX XRF core scanner from a laminated sediment core from the Laguna de Juanacatlán, western central Mexico yield a unique high-resolution record of runoff (precipitation) change for the last 2000 years. In the absence of reliable, long-term meteorological records, comparison of the Ti data with information from the rich Spanish colonial period archives and the post-Independence period, confirms that Ti is a proxy for runoff. This interpretation is supported by comparison with other high-resolution archives from the surrounding region, primarily tree rings and other lake sediment sequences. The Juanacatlán Ti record is therefore a proxy for summer, monsoonal rainfall. The record provides new evidence from the Pacific margin of tropical North America of the occurrence of dry conditions through much of the Classic period ( c. AD 300—900), and wetter conditions during the later Medieval period ( c. AD 1200—1350). The period commonly known as the ‘Little Ice Age’ (LIA) shows considerable variability, with dry conditions in the early part ( c. AD 1400—1600) and wetter conditions, punctuated by multiyear droughts through the eighteenth century. A notable feature of the record is the apparent decoupling of lacustrine sedimentation from the climate since the mid-twentieth century, possibly resulting from anthropogenic disturbance. Preliminary interpretations of the Ti record indicate that patterns are consistent with changes in monsoon strength associated with ENSO and solar forcing over the last two millennia.
Hematological and toxicological evaluation of formaldehyde as a potential cause of human leukemia
Authors: Goldstein Bernard D
Published: August 2010

Epidemiological findings suggesting that formaldehyde exposure is associated with a higher risk of acute myelogenous leukemia (AML) and other hematological cancers have led to consideration of the potential mechanism of action by which inhalation of this rapidly reactive agent can cause bone marrow cancer. Two major mechanism-based arguments against formaldehyde as a leukemogen have been the difficulty in envisioning how inhaled formaldehyde might penetrate to the bone marrow; and the lack of similarity of non-cancer effects to other known human myeloleukemogens, particularly the absence of pancytopenia in humans or laboratory animals exposed to high levels. However, both of these arguments have been addressed by the recent finding of a pancytopenic effect and chromosomal abnormalities in heavily exposed Chinese workers which, if replicated, are indicative of a genotoxic effect of formaldehyde on hematopoietic stem cells that is in keeping with other known human leukemogens. Review of the body of evidence suggests an apparent discrepancy between studies in laboratory animals, which generally fail to show evidence of penetration of formaldehyde into the blood or evidence of blood or bone marrow genotoxicity, and studies of exposed humans in which there tends to be evidence of genotoxicity in circulating blood cells. One possible explanation for this discrepancy is species difference. Another possible explanation is that myeloid precursors within the nasal mucosa may be the site for leukemogenesis. However, chloromas, which are local collections of myeloid tumor cells, are rarely if ever found in the nose. Other proposed mechanisms for formaldehyde leukemogenesis are reviewed, and dose issues at the interface between the epidemiological and hematotoxicological findings are explored.
“You Know What I Mean:” The Ethical and Methodological Dilemmas and Challenges for Black Researchers Interviewing Black Families
Authors: Ochieng Bertha M. N.
Published: August 2010

In this article I provide a reflexive account of my research experiences with families of African descent. I examine the ways in which, as a researcher of African descent, I became part of the research process. Using data from an ethnographic study that explored the healthy lifestyle experiences and attitudes of families and adolescents of African descent in the northwest of England, I present a detailed discussion of the identity alteration, researcher—researched relationships, and insider—outsider tensions and dilemmas that arose while I collected data. I argue that researchers working with participants with whom they share similar ethnicity and historical experiences are likely to find that their professional self and personal life experiences overlap, and there can be difficulties in keeping them separate.
Relevance of cognitive deterioration in early relapsing-remitting MS: a 3-year follow-up study
Authors: Amato Maria P , Portaccio Emilio , Goretti Benedetta , Zipoli Valentina , Iudice Alfonso , Pina Dario Della , Malentacchi Gianmichele , Sabatini Simonetta , Annunziata Pasquale , Falcini Mario , Mazzoni Monica , Mortilla Marzia , Fonda Claudio , De Stefano Nicola ,   TuSCIMS Study Group
Published: August 2010

Objective: To assess longitudinally cognitive functioning in relapsing—remitting multiple sclerosis (RRMS) patients and its relationship with clinical and MRI variables.

Methods: Early RRMS patients and matched healthy controls were assessed in parallel in three testing sessions over 3 years, using the Rao’s Brief Repeatable Battery of Neuropsychological Tests. Patients also underwent an MRI analysis of T2-weighted lesion volume (T2LV), number of gadolinium-enhanced lesions and whole brain atrophy. Forty-nine RRMS patients (mean age 36.9 ± 8.9 years; mean disease duration 2.9 ± 1.7 years, mean Expanded Disability Status Scale, 1.7 ± 0.7) and 56 healthy controls were recruited.

Results: At baseline, cognitive impairment was detected in 15 patients (30.6%). After 3 years, cognitive functioning worsened in the 29.3% of patients, whereas Expanded Disability Status Scale progression was observed in only three patients. The most sensitive test to detect cognitive deterioration over time was the Symbol Digit Modalities Test (SDMT). Only the presence of moderate cognitive impairment at baseline predicted further cognitive deterioration ( p = 0.03). Among MRI variables, T2LV showed a weak to moderate relationship with some cognitive tasks.

Conclusions: Over a 3-year period cognitive deterioration can be expected in approximately one-third of MS patients with relatively short disease duration. The SDMT is particularly suitable for longitudinal assessment of MS-related cognitive changes.
Application of Hydroturbine Pump in Water Source Heat Pump Drainage Gravitational Potential Energy Recovery System
Authors: Jun Lu  , Yunqing Fan  , Jingna Song  , Huayu Tang  , Chuck Yu
Published: August 2010

In this study, an energy recovery water source heat pump (ERWSHP) system has been developed and evaluated for feasibility, parameter efficiency and energy saving potential in comparison to conventional water source heat pump (WSHP) systems. The water discharged from the heat exchanger at a height, with an elevation difference of approximately 30 m in some areas of the mountainous city of Chongqing, was utilised as gravitational potential energy (GPE) which is converted into mechanical shaft power to drive the hydroturbine pump. A prototype of the system was set up, characterised, parameter tested and optimised in the laboratory at Chongqing University. MATLAB curve tool (cftool) was utilised to fit the characteristic curves under different water heads. The test data obtained were compared with the standard supplied data to ensure that the measurement was consistent with the performance expected. The system was validated by application to an off-site office development where the hourly cooling load during summer and heating load during winter was assessed using DeST-c (Designer’s Simulation Toolkits). The influence of the parameters was also evaluated. The energy-saving rates of ERWSHP systems in summer and winter were 37.5% and 60.1%, respectively, an equivalent to a fuel reduction of 14.7 tons of coal in summer and 31.8 tons during the winter. The use of GPE would also reduce water intake and increase the total transfer efficiency from 60% to 75% for the hydroturbine pump. A saving of 1131.01 kJ per year, a peak saving rate of 20.8%, in energy consumption could be achieved using the system.
Mechanisms for Understanding the Facilitators and Barriers to Capacity Building for Chronic Disease Prevention Activities
Authors: Flaman Laura M. , Plotnikoff Ronald C. , Nykiforuk Candace I. J. , Raine Kim
Published: August 2010

This study explored facilitators and barriers to capacity building for chronic disease prevention (CDP) activities with participants in community-based workshops on environments related to CDP. Three phases of research were conducted. Worksheet analysis (Phase A) indicated that participants ( n = 34) identified priority strategies related to the physical environment as a primary focus for CDP, followed by sociocultural, economic, and political environments. Questionnaire completion (Phase B; n = 17) indicated that individuals’ capacity was inhibited by a lack of organizational infrastructure (particularly, resources and public and research support). Interviews (Phase C; n = 11) revealed five factors that limited participants’ capacity: (a) organizations’ lack of competing priorities, (b) priorities secondary to the organizational mandate, (c) disconnect between organizational and government or funder priorities, (d) limited resources, and (e) larger community issues. Implications for research and practice are discussed.
An Examination of Questionnaire Evaluation by Expert Reviewers
Authors: Olson Kristen
Published: August 2010

Expert reviews are frequently used as a questionnaire evaluation method but have received little empirical attention. Questions from two surveys are evaluated by six expert reviewers using a standardized evaluation form. Each of the questions has validation data available from records. Large inconsistencies in ratings across the six experts are found. Despite the lack of reliability, the average expert ratings successfully identify questions that had higher item nonresponse rates and higher levels of inaccurate reporting. This article provides empirical evidence that experts are able to discern questions that manifest data quality problems, even if individual experts vary in what they rate as being problematic. Compared to a publicly available computerized question evaluation tool, ratings by the human experts positively predict questions with data quality problems, whereas the computerized tool varies in success in identifying these questions. These results indicate that expert reviews have value in identifying question problems that result in lower survey data quality.
Cancer registries: a novel alternative to long-term clinical trial follow-up based on results of a comparative study
Authors: Qian Shi  , You Y Nancy , Nelson Heidi , Allen Mark S , Winchester David , Stewart Andrew , Young-Fadok Tonia , Decker Paul A , Green Erin M , Holton Sara J , Ballman Karla V
Published: August 2010

Background Data collection and review were identified as major contributors to the cost of randomized clinical trials (RCTs).

Purpose We proposed and assessed a novel alternative for long-term clinical trial follow-up based on the data captured through an accredited Cancer Registry (CR) that is part of the National Cancer Database (NCDB).

Methods Patients from Mayo Clinic, Rochester, enrolled in the North Central Cancer Treatment Group N934653 (COST) trial (98 patients) and the American College of Surgeons Oncology Group Z0030 trial (55 patients) were included in the study. Demographic, treatment, and long-term outcome data were compared between the hospital-based CR and the RCTs’ databases. Concordances were used to estimate the agreement between two databases. Kaplan—Meier curves were plotted to examine the consistency of time-to-event long-term outcomes of the CR and RCT databases.

Results High concordances (>95%) were observed for most demographic and treatment variables between the CR data and RCT data. The vital status concordances were 100% and 94.5% between the CR and COST and Z0030 databases, respectively. Three discrepant death dates were observed, one in the COST trial and two in the Z0030 trial. The concordances of disease-free status between the CR and RCT databases were 99.0% and 87.3%, and 15 discrepant disease recurrence cases were identified: 4 for COST and 11 for Z0030. Limitations The analysis has been focused on patients from a single site, Mayo Clinic, Rochester, enrolled in two large RCT evaluating surgical treatments. The findings herein need to be confirmed in a broader setting, such as multi-center, multi-registry including nonsurgical trials.

Conclusions CR data were nearly identical to data from two randomized phase III trials in different disease types and conducted by two different cooperative groups. The NCDB Cancer Registries represent a feasible alternative for obtaining long-term follow-up data for large clinical trials. Clinical Trials 2010; 7: 686—695. http:// ctj.sagepub.com
Efficacy of a synbiotic supplementation in the prevention of common winter diseases in children: a randomized, double-blind, placebo-controlled pilot study
Authors: Cazzola Mario , Pham-Thi Nhân , Kerihuel Jean-Charles , Durand Henri , Bohbot Serge
Published: August 2010

Background and aims: The purpose of this study was to investigate the efficacy of a synbiotic supplementation in reducing common winter diseases in children.

Methods: A randomized, double-blind, placebo-controlled, multicentre study was conducted in young school-age children (3—7 years old) during a winter period. Participants were otherwise healthy children who suffered from at least three episodes of ear, nose and throat (ENT), respiratory tract or gastrointestinal illness during the previous winter. They were supplemented daily with either a synbiotic preparation (Lactobacillus helveticus R0052, Bifidobacterium infantis R0033, Bifidobacterium bifidum R0071, and fructooligosaccharide) or a matched placebo for 3 months. Over this period, all emergent health episodes of any type were recorded by parents in a diary. They were checked by investigators at regular monthly visits. The main study outcome was the percentage of children free of any episode during the study course.

Results: We randomized 135 children (mean age: 4.1±1.0 years) to the synbiotic group ( n = 62) or placebo ( n = 73) group. At least one illness episode was reported in 32 children in the synbiotic group and 50 in the placebo group (51.6% versus 68.5%). This corresponded to a significant 25% relative risk reduction (95% CI 0.6—44.3%; p = 0.045). This difference was due to a decrease in the number of children who suffered from at least one ENT, respiratory tract or gastrointestinal disorder (50.0% with synbiotic versus 67.1% with placebo; p = 0.044). At least one sickness school day loss was noted in 25.8% of children with the synbiotic as compared with 42.5% with placebo ( p = 0.043). No treatment related side effects were detected in either group.

Conclusions: This study suggests that a 3-month supplementation with this synbiotic preparation can decrease the risk of occurrence of common infectious diseases in children and limits the risk of school day loss.
Rare Detection of Fat Emboli During Venous Duplex Sonography
Authors: Washko Patrick A. , Wayne Smith S. , Barbour Kelly , Cheek Rosa , Reese Savannah , Schmanke David , Stull Brian
Published: August 2010

Fat embolism syndrome (FES) is defined as a variant of posttraumatic pulmonary insufficiency following long-bone musculoskeletal trauma or surgical repair. FES is a serious life-threatening complication characterized by the simultaneous occurrence of pulmonary and neurological symptoms as well as skin and mucosal petechiae. Although frequently asymptomatic and commonly seen following bone manipulation, fatty emboli are rarely found in patients undergoing total joint arthroplasty. Embolic signals from fatty emboli have been detected by transesophageal echocardiography (TTE) and transcranial Doppler (TCD); however, they have rarely been documented in the lower extremity. A patient is described with multiple fatty emboli demonstrated during a venous duplex examination.
Extensive Nonunion of the Amnion: An Unusual Presentation of Amniotic Band Syndrome?
Authors: Hill Donald Stephen
Published: August 2010

Amniotic band syndrome is a relatively rare condition affecting approximately 1 in 1200 live births, where the amniotic membrane ruptures from the chorion, leaving the fetus exposed to injury due to entrapment of body parts within the membranous strands. This case demonstrates what appears to be virtually complete nonunion, or complete rupture of the amnion from the chorion with deformity and amputation of a fetal foot and toes revealed at birth.
Association of airflow limitation with trauma exposure and post-traumatic stress disorder
Authors: Spitzer C. , Koch B. , Grabe H.J. , Ewert R. , Barnow S. , Felix S.B. , Ittermann T. , Obst A. , Völzke H. , Gläser S. , Schäper C.
Published: August 2010

Trauma exposure and post-traumatic stress disorder (PTSD) are associated with self-reported asthma and chronic obstructive pulmonary disease. However, these conditions have not yet been related to objective measures of lung function.

1,772 adults from the general population were assessed regarding their medical histories and spirometric lung function. Additionally, they were administered a PTSD interview, and assigned to three groups: no trauma; trauma, but no PTSD; and trauma with PTSD.

Adjusting for sociodemographic, clinical and lifestyle factors, subjects with PTSD had significantly higher odds ratios for most asthma-related symptoms than PTSD-negative participants (OR 3.2–8.8). The mean ratio of forced expiratory volume in 1 s (FEV1) to forced vital capacity (FVC) was lowest in the PTSD group and highest in those without trauma exposure. Traumatic stress was independently associated with FEV1and FEV1/FVC. Participants with PTSD, compared with those without, had a significantly increased risk for airflow limitation independent of its definition (OR 4.2–7.8).

This is the first study relating traumatic stress and PTSD, respectively, to objective parameters of lung function. Our findings suggest an association of trauma exposure and PTSD with airflow limitation, which may be mediated by inflammatory processes.
Dynamic changes in cellular infiltrates with repeated cutaneous vaccination: a histologic and immunophenotypic analysis
Authors: Schaefer Jochen T , Patterson James W , Deacon Donna H , Smolkin Mark E , Petroni Gina R , Jackson Emily M , Slingluff Craig L
Published: August 2010

Background

Melanoma vaccines have not been optimized. Adjuvants are added to activate dendritic cells (DCs) and to induce a favourable immunologic milieu, however, little is known about their cellular and molecular effects in human skin. We hypothesized that a vaccine in incomplete Freund's adjuvant (IFA) would increase dermal Th1 and Tc1-lymphocytes and mature DCs, but that repeated vaccination may increase regulatory cells.

Methods

During and after 6 weekly immunizations with a multipeptide vaccine, immunization sites were biopsied at weeks 0, 1, 3, 7, or 12. In 36 participants, we enumerated DCs and lymphocyte subsets by immunohistochemistry and characterized their location within skin compartments.

Results

Mature DCs aggregated with lymphocytes around superficial vessels, however, immature DCs were randomly distributed. Over time, there was no change in mature DCs. Increases in T and B-cells were noted. Th2 cells outnumbered Th1 lymphocytes after 1 vaccine 6.6:1. Eosinophils and FoxP3+ cells accumulated, especially after 3 vaccinations, the former cell population most abundantly in deeper layers.

Conclusions

A multipeptide/IFA vaccine may induce a Th2-dominant microenvironment, which is reversed with repeat vaccination. However, repeat vaccination may increase FoxP3+T-cells and eosinophils. These data suggest multiple opportunities to optimize vaccine regimens and potential endpoints for monitoring the effects of new adjuvants.

Trail Registration

ClinicalTrials.gov Identifier: NCT00705640
Polymorphisms in the glucocorticoid receptor gene that modulate glucocorticoid sensitivity are associated with rheumatoid arthritis
Authors: van Oosten Manon JM , Dolhain Radboud JEM , Koper Jan W , van Rossum Elisabeth FC , Emonts Marieke , Han Khik H , Wouters Jacques MGW , Hazes Johanne MW , Lamberts Steven WJ , Feelders Richard A
Published: August 2010

Introduction

The glucocorticoid receptor (GR) plays an important regulatory role in the immune system. Four polymorphisms in the GR gene are associated with differences in glucocorticoid (GC) sensitivity; the minor alleles of the polymorphisms N363 S and BclI are associated with relative hypersensitivity to GCs, while those of the polymorphisms ER22/23EK and 9β are associated with relative GC resistance. Because differences in GC sensitivity may influence immune effector functions, we examined whether these polymorphisms are associated with the susceptibility to develop Rheumatoid Arthritis (RA) and RA disease severity.

Methods

The presence of GR polymorphisms was assessed in healthy controls (n = 5033), and in RA patients (n = 368). A second control group (n = 532) was used for confirmation of results. In RA patients, the relationship between GR polymorphisms and disease severity was examined.

Results

Carriers of the N363 S and BclI minor alleles had a lower risk of developing RA: odds ratio (OR) = 0.55 (95% confidence interval (CI) 0.32-0.96, P = 0.032) and OR = 0.73 (95% CI 0.58-0.91, P = 0.006), respectively. In contrast, 9β minor allele carriers had a higher risk of developing RA: OR = 1.26 (95% CI 1.00-1.60, P = 0.050). For ER22/23EK minor allele carriers a trend to an increased risk OR = 1.42 (95% CI 0.95-2.13, P = 0.086) was found. All ER22/23EK carriers (32/32) had erosive disease, while only 77% (259/336) of the non-carriers did (P = 0.008). In addition, ER22/23EK carriers were treated more frequently with anti-tumor necrosis factor-alpha (TNFα) therapy (P < 0.05).

Conclusions

The minor alleles of the 9β and ER22/23EK polymorphisms seem to be associated with increased predisposition to develop RA. Conversely, the minor alleles of the N363 S and BclI polymorphisms are associated with reduced susceptibility to develop RA. These opposite associations suggest that constitutionally determined GC resistance may predispose to development of auto-immunity, at least in RA, and vice versa.
The Silence of the Last Poet: Matthew Arnold, T. S. Eliot, and the Value of the Classic
Authors: Hentea Marius
Published: August 2010

This essay explores the conceptions of the classic, and of literary value more generally, in T. S. Eliot's “What Is a Classic?” and Matthew Arnold's “Study of Poetry.” Eliot's address heavily depends on Arnold's study, but there are significant points of difference, especially when it comes to the question of Homer and Virgil. Fundamentally, though, both Arnold and Eliot reach toward a transcendental, even religious, view of the classic. The essay concludes by developing the implications of Eliot's “last poet” and the silencing qualities of the classic hinted at in his address. These qualities have not been sufficiently understood, but taking them seriously shows why the current defense of the classic is dubious.
Robots and Service Innovation in Health Care
Authors: Oborn Eivor , Barrett Michael , Darzi Ara
Published: August 2010

Robots have long captured our imagination and are being used increasingly in health care. In this paper we summarize, organize and criticize the health care robotics literature and highlight how the social and technical elements of robots iteratively influence and redefine each other. We suggest the need for increased emphasis on sociological dimensions of using robots, recognizing how social and work relations are restructured during changes in practice. Further, we propose the usefulness of a ‘service logic’ in providing insight as to how robots can influence health care innovation.
Prevalence of fluorosis in an endemic village in central India
Authors: Pandey Aparna
Published: August 2010

Endemic fluorosis is an important public health problem in certain parts of the Durg district of Chhattisgarh. The aim of the study was to find out the prevalence of dental and skeletal fluorosis among the population and to assess the relation between drinking water fluoride level and prevalence of fluorosis. A cross-sectional survey was undertaken in Gureda Village, of the Durg district of Chhattisgarh state in October 2009. The survey covered 805 individuals – 362 males and 443 females. The prevalence of dental and skeletal fluorosis was assessed based on clinical examinations of individuals. Drinking and eating habits of individuals were recorded as per checklist. Water fluoride levels of prime water sources were also determined by lab examination. The prevalence of dental fluorosis was 8.2%. Both skeletal and dental fluorosis were more common in males. Dental fluorosis was higher in the 8–45 age group, whereas the prevalence of skeletal fluorosis increased with age. Genu varum (38.1%) and genu vulgum (6.3%) were the common skeletal deformities. Water fluoride levels ranged from 0.2 to 7.8 ppm.
Nested Simulation in Portfolio Risk Measurement
Authors: Gordy Michael B. , Juneja Sandeep
Published: August 2010

Risk measurement for derivative portfolios almost invariably calls for nested simulation. In the outer step, one draws realizations of all risk factors up to the horizon, and in the inner step, one reprices each instrument in the portfolio at the horizon conditional on the drawn risk factors. Practitioners may perceive the computational burden of such nested schemes to be unacceptable and adopt a variety of second-best pricing techniques to avoid the inner simulation. In this paper, we question whether such short cuts are necessary. We show that a relatively small number of trials in the inner step can yield accurate estimates, and we analyze how a fixed computational budget may be allocated to the inner and the outer step to minimize the mean square error of the resultant estimator. Finally, we introduce a jackknife procedure for bias reduction.
Seller Search and Market Outcomes in Online Auctions
Authors: Kuruzovich Jason , Viswanathan Siva , Agarwal Ritu
Published: August 2010

It has become widely accepted that information technology (IT) has had a profound influence on market transactions, with lower search costs for buyers often considered the key to lower prices and higher consumer welfare. However, sellers also use online channels to search for buyers whose product preferences and valuations match the sellers' offerings, and limited research has examined the impact of IT on sellers' search strategies or associated market outcomes. In this study, we investigate how market characteristics, the length of time the seller searches the auction marketplace for a buyer, and seller search in other websites influence the final sale price in online auctions. The online auction market for used vehicles provides a valuable opportunity to observe search processes of sellers, as the unique vehicle identification number associated with each vehicle enables the tracking of an individual item across both subsequent auctions and across other websites. We find that the market characteristics, duration of search, and search in other websites are each associated with a higher final sale price. Our findings highlight the importance of examining both buyer and seller search behaviors to further our understanding of the impacts of IT on market outcomes and efficiency.
PERSPECTIVE—Researchers Should Make Thoughtful Assessments Instead of Null-Hypothesis Significance Tests
Authors: Schwab Andreas , Abrahamson Eric , Starbuck William H. , Fidler Fiona
Published: August 2010

Null-hypothesis significance tests (NHSTs) have received much criticism, especially during the last two decades. Yet many behavioral and social scientists are unaware that NHSTs have drawn increasing criticism, so this essay summarizes key criticisms. The essay also recommends alternative ways of assessing research findings. Although these recommendations are not complex, they do involve ways of thinking that many behavioral and social scientists find novel. Instead of making NHSTs, researchers should adapt their research assessments to specific contexts and specific research goals, and then explain their rationales for selecting assessment indicators. Researchers should show the substantive importance of findings by reporting effect sizes and should acknowledge uncertainty by stating confidence intervals. By comparing data with naïve hypotheses rather than with null hypotheses, researchers can challenge themselves to develop better theories. Parsimonious models are easier to understand, and they generalize more reliably. Robust statistical methods tolerate deviations from assumptions about samples.
CROSSROADS—Microfoundations of Performance: Balancing Efficiency and Flexibility in Dynamic Environments
Authors: Eisenhardt Kathleen M. , Furr Nathan R. , Bingham Christopher B.
Published: August 2010

Our purpose is to clarify the microfoundations of performance in dynamic environments. A key premise is that the microfoundational link from organization, strategy, and dynamic capabilities to performance centers on how leaders manage the fundamental tension between efficiency and flexibility. We develop several insights. First, regarding structure, we highlight that organizations often drift toward efficiency, and so balancing efficiency and flexibility comes, counterintuitively, through unbalancing to favor flexibility. Second, we argue that environmental dynamism, rather than being simply stable or dynamic, is a multidimensional construct with dimensions that uniquely influence the importance and ease of balancing efficiency and flexibility. Third, we outline how executives balance efficiency and flexibility through cognitively sophisticated, single solutions rather than by simply holding contradictions. Overall, we go beyond the caricature of new organizational forms as obsessed with fluidity and the simplistic view of routines as the microfoundation of performance. Rather, we contribute a more accurate view of how leaders effectively balance between efficiency and flexibility by emphasizing heuristics-based “strategies of simple rules,” multiple environmental realities, and higher-order “expert” cognition. Together, these insights seek to add needed precision to the microfoundations of performance in dynamic environments.
Better with Age? Tie Longevity and the Performance Implications of Bridging and Closure
Authors: Baum Joel A. C. , McEvily Bill , Rowley Tim J.
Published: August 2010

We examine the extent to which performance effects of firms' network positions vary with the ages of the ties comprising those positions. Our analysis of Canadian investment banks' underwriting syndicate ties indicates that the performance benefits of closure ties increase with age, whereas benefits of bridging ties decrease with age. We also find that benefits yielded by hybrid network positions, combining elements of both closure and bridging, are greatest when old closure ties are combined with either very young or very old bridging ties. Our findings support the idea that the advantages firms gain (or do not) from their network positions depend on the relational character of the ties comprising them, highlighting the risk of theorizing structural network effects without also considering the relational and temporal dynamics associated with network positions.
New Product Exploration Under Environmental Turbulence
Authors: Danneels Erwin , Sethi Rajesh
Published: August 2010

This study identifies two organizational factors that foster explorative products, willingness to cannibalize and future-oriented market scanning, and examines whether the relationships of these factors with exploration are contingent on environmental turbulence in customer, competitor, and technological sectors. The study analyzes data from 145 U.S. public manufacturing firms to examine the relationship between the two organizational factors and the degree to which the firms pursue explorative new products—new products that are meaningfully distinct from competing alternatives. Results suggest that both willingness to cannibalize and future-oriented market scanning promote explorative new products. The relationship of willingness to cannibalize with explorative products is stronger under customer turbulence. In contrast, the relationship of future-oriented market scanning with explorative products is weaker under customer and competitive turbulence and stronger under technological turbulence. The study concludes that the two organizational factors promote explorative new products, but their effectiveness is contingent on turbulence in different sectors of the firm's environment.
A participação nos conselhos de saúde e sua interface com a cultura política
Authors: Oliveira Lucia Conde de , Pinheiro Roseni
Published: August 2010

O objetivo deste estudo é analisar as práticas de participação presentes no Conselho Municipal de Saúde de uma capital do Nordeste brasileiro e sua relação com a cultura política local. Partiu-se do seguinte pressuposto teórico: as práticas de participação exercidas nos conselhos de saúde inauguram uma nova institucionalidade, que inclui novos sujeitos sociais - os usuários - na esfera pública. O processo de democratização da sociedade brasileira amplia essa esfera e dá visibilidade para o confronto entre uma cultura política tradicional e outra democrática. Tratase de uma pesquisa qualitativa com as seguintes técnicas de coleta de dados: análise documental, observação participante e entrevista semiestruturada. Nas evidências surgidas, identificou-se a predominância da cultura política tradicional como um dos condicionantes das práticas de participação no conselho, expressa no autoritarismo e cooptação nas relações entre os gestores municipais e os representantes da sociedade civil. A maioria dos conselheiros reconhece o frágil poder deliberativo e fiscalizador do conselho. Apesar de se constatar as fragilidades dos conselhos de saúde, reconhece-se sua importância na democratização da relação entre Estado e sociedade civil e na luta para efetivação do direito à saúde.
Evaluation methods in health promotion programmes: the description of a triangulation in Brazil
Authors: Souza Elza Maria de
Published: August 2010

Evaluation is a key word in any health promotion programme. However, it is a challenge to choose the most appropriate method of evaluation. The purpose of this paper was to describe a triangulated methodology developed to evaluate a health promotion intervention based on intergenerational activities and to describe the theoretical framework, which guided the study. From February to December 2002 a triangulation involving a community controlled trial, focus groups technique and observation process was developed in Ceilândia, Federal District of Brazil. Samples of 253 students aged 12 to 18 years old from a secondary school and 266 elders aged 60 and over from the local area were randomly allocated to control and experimental groups. Over four months, 111 students and 32 elders had weekly meetings at school to share their life histories. Before and after the intervention, a questionnaire was administered to control and experimental groups including the outcome variables. Although the study had some limitations, it was valuable in showing for the first time that this method can be used in interventions of this kind and also to show the importance of developing a theoretical framework to understand possible mechanism of interactions in intergenerational interventions.
Experiments on the piping behavior of geofiber-reinforced soil
Authors: Das A. , Viswanadham B.V.S.
Published: August 2010

ABSTRACT: The objective of this paper is, through laboratory experiments, to examine the effect of discrete and randomly distributed fibers on the piping behavior of soil. A silty sand type of soil having 20% fines was selected in the present study. Two types of geofiber, polypropylene and polyester, were used. In this work, various experiments were carried out to determine the influence of geofibers with various dosages and lengths on the seepage velocity and piping resistance of soil. A fiber dosage up to 0.15% only was adopted. It was observed that geofibers increased the critical hydraulic gradient and caused a significant delay in piping phenomena. The observed piping behavior of soil with and without geofibers was verified by conducting constant-load tests in the laboratory. Based on the analysis and interpretation of these experiments, the mechanism of discrete fiber reinforcement in restraining piping of soil is explained.
An analytical method to predict the pullout response of geotextiles
Authors: Weerasekara L. , Wijewickreme D.
Published: August 2010

ABSTRACT: Understanding the pullout mechanism of geotextiles is a key consideration in analyzing the stability of geotextile/reinforced-soil structures. The analytical models developed based on linear behavioral assumptions for the geotextile material stress–strain response have significant limitations in capturing the highly nonlinear pullout response observed in relatively extensible geotextiles. A new analytical model was developed combining the nonlinear responses of the geotextile and soil–geotextile interface characteristics. The interface behavior was modeled considering the changes in normal stress on the planar geotextile due to constrained dilation of soil and the subsequent frictional degradation behaviors at the interface. The analytical solution is useful in predicting the pullout resistances, strain, and mobilized frictional length along the geotextile for a given magnitude of displacement. The suitability of the analytical formulation was verified by predicting the experimentally observed performance of several geotextile pullout tests conducted with varying geotextile material and burial conditions. A simple chart and equation capable of predicting strain and mobilized frictional length, respectively, for a given magnitude of relative geotextile displacement are proposed, based on the research findings.
Use of coir geotextiles in unpaved road construction
Authors: Vinod P. , Minu M.
Published: August 2010

ABSTRACT: This paper reports the beneficial effect of five varieties of coir product inclusion (three types of woven coir geotextile and two types of hand-knotted coir netting) on the California bearing ratio (CBR) behaviour of four soils: a natural soft clay; a commercially available soft clay; lateritic soil; and sand over soft clay subgrade. The study indicates that CBR improvement sufficient to eliminate the need for a strong base course in unpaved roads is achievable through the use of these coir products. Woven coir geotextiles are found to perform much better (about a twofold improvement) than hand-knotted coir nettings (about a 1.5-fold improvement). Lateral confinement of the soil within the cells of the geotextile/netting is identified as the principal reinforcement mechanism. The general strength mobilisation theory applicable to geosynthetic reinforcements, according to which the lower the CBR value of the subgrade is, the higher is the degree of improvement due to reinforcement inclusion, is not valid for coir geotextiles and nettings. The paper also highlights the importance of testing under soaked conditions, even for non-swelling soils.
Protection of buried pipes against accidental damage using geosynthetics
Authors: Palmeira E.M. , Andrade H.K.P.A.
Published: August 2010

ABSTRACT: Buried pipes can be damaged by accidents, or by the action of vandalism. Depending on the material transported by the pipe and its pressure, serious consequences can result from such damage, which commonly involve great material losses and, unfortunately, losses of lives. This paper presents a model study on the influence of the presence of geosynthetic reinforcement to minimise the effects on a buried pipe caused by the penetration of a rigid object in the ground. Different types of reinforcements and reinforcement arrangements were tested. The penetrating object was driven in the ground under different inclinations to the vertical direction. Besides the force applied to the object, total stresses in the ground and pipe strains were measured. The results obtained showed the beneficial effect of the reinforcement presence in increasing the force necessary for object penetration, as well as in reducing total stresses and strains in the pipe. The reinforcement arrangement with the geosynthetic layer enveloping the pipe was the one that performed best.
A 28-Pulse AC-DC Converter Based SMPS for Telecom Power Supply
Authors: Kalpana R. , Bhuvaneswari G. , Singh Bhim , Singh Shikha , Gairola Sanjay
Published: August 2010

This paper presents a new 28-pulse ac-dc converter for enhancing the power quality at the point of common coupling, while feeding a medium capacity switched mode power supply (SMPS). It consists of two series connected 14-pulse ac-dc uncontrolled converters fed by seven phase-shifted ac voltages. The proposed converter is found capable of suppressing up to 27 harmonic currents in the ac mains. The power factor is also improved to near unity over a wide operating range of the SMPS. The design and analysis of the proposed ac-dc converter is carried-out in detail. A laboratory prototype of the autoconnected transformer based 28-pulse ac-dc converter is developed, and various tests have been conducted on it to validate the simulated performance of the proposed converter. Several experimental results are also included to show the effectiveness and robustness of the proposed converter.
Socioeconomic Differences in Tranquillizer Use Among Spanish Adolescents
Authors: Gil-Lacruz Ana I. , Gil-Lacruz Marta
Published: August 2010

We investigated the socioeconomic determinants of tranquillizer use among Spanish teenagers. Highlighting these differences may help health professionals to be more effective in their diagnosis and corresponding prescriptions as well as supporting social agencies in designing better
prevention strategies. We focused on Spanish society with data drawn from the Spanish Survey on Drug Use in School Populations (Spanish Drug Observatory, 2000, 2002, and 2004).
The Effects of User Perception of Value on Use of Blog Services
Authors: Pi Shih-Ming , Liao Hsiu-Li , Liu Su-Houn , Hsieh Chia-Yu
Published: August 2010

A weblog (blog) is a form of online technology that has the potential to be a teaching tool by creating a contact point between the teacher and the learner. In this study we used an Internet questionnaire to investigate teaching-related activities, with 187 blog users. The results of
the statistical analysis provide several conclusions: a positive perception of value positively influences continued intention to use; convenience of use positively influences user perception of value; interaction; personalization; service compatibility; and cognitive effort all positively
influence user perception of value.
The Influence of Project-Based Curricula on Six-Year-Old Preschoolers' Conceptual Development
Authors: Aral Neriman , Kandir Adalet , Ayhan Aynur Bütün , Yaşar Münevver Can
Published: August 2010

The aim in this study was to understand the effects of project-based curricula on 6-year-old preschool children's conceptual development. Two classes of 14 preschoolers were assigned at random, 1 to the experimental group and the other to the control group. The experimental children's
group took part in project-based education for a total of 12 weeks while the control group followed the regular preschool curriculum. Data about the children's conceptual development were gathered using the Bracken Basic Concept Scale-Revised (Bracken, 1998), which was previously adapted for
6-year-old Turkish children by Bütün Ayhan and Aral (2007). The results revealed that all children improved their scores between the time of pretest and posttest, but there was a small difference in favor of the experimental group in the posttest scores.
Body Satisfaction and Overall Mood: Effects of Race in Exercisers with Obesity
Authors: Annesi James J. , Gorjala Srinivasa
Published: August 2010

Body image in obese women is generally poor, and may be affected by race/ethnicity. The impact of exercise is unclear. White and African American women who were obese started on a supported exercise and nutrition education program for weight reduction. The body satisfaction of the African
American participants was significantly more favorable at baseline than the comparable group of White women. For all participants, body satisfaction was significantly related to overall mood, both at baseline, and in its significant improvements over six months. Race/ethnicity did not influence
those relationships. Extensions of this research may improve theory and, ultimately, treatments.