Showing papers by "The Chinese University of Hong Kong published in 2010"
TL;DR: The findings of both the contingency and configuration approach indicated that SCI was related to both operational and business performance, and indicated that internal and customer integration were more strongly related to improving performance than supplier integration.
2,535 citations
05 Sep 2010
TL;DR: The guided filter is demonstrated that it is both effective and efficient in a great variety of computer vision and computer graphics applications including noise reduction, detail smoothing/enhancement, HDR compression, image matting/feathering, haze removal, and joint upsampling.
Abstract: In this paper, we propose a novel type of explicit image filter - guided filter. Derived from a local linear model, the guided filter generates the filtering output by considering the content of a guidance image, which can be the input image itself or another different image. The guided filter can perform as an edge-preserving smoothing operator like the popular bilateral filter [1], but has better behavior near the edges. It also has a theoretical connection with the matting Laplacian matrix [2], so is a more generic concept than a smoothing operator and can better utilize the structures in the guidance image. Moreover, the guided filter has a fast and non-approximate linear-time algorithm, whose computational complexity is independent of the filtering kernel size. We demonstrate that the guided filter is both effective and efficient in a great variety of computer vision and computer graphics applications including noise reduction, detail smoothing/enhancement, HDR compression, image matting/feathering, haze removal, and joint upsampling.
2,215 citations
TL;DR: In this article, the authors examine a potential benefit associated with the initiation of voluntary disclosure of corporate social responsibility (CSR) activities: a reduction in firms' cost of equity capital.
Abstract: We examine a potential benefit associated with the initiation of voluntary disclosure of corporate social responsibility (CSR) activities: a reduction in firms’ cost of equity capital. We find that firms with a high cost of equity capital in the previous year tend to initiate disclosure of CSR activities in the current year and that initiating firms with superior social responsibility performance enjoy a subsequent reduction in the cost of equity capital. Further, initiating firms with superior social responsibility performance attract dedicated institutional investors and analyst coverage. Moreover, these analysts achieve lower absolute forecast errors and dispersion. Finally, we find that firms exploit the benefit of a lower cost of equity capital associated with the initiation of CSR disclosure. Initiating firms are more likely than non-initiating firms to raise equity capital following the initiations and among firms raising equity capital, initiating firms raise a significantly larger amount than do non-initiating firms.
2,153 citations
15 Apr 2010
TL;DR: Systematic studies of more than 25,000 cancer genomes will reveal the repertoire of oncogenic mutations, uncover traces of the mutagenic influences, define clinically relevant subtypes for prognosis and therapeutic management, and enable the development of new cancer therapies.
Abstract: The International Cancer Genome Consortium (ICGC) was launched to coordinate large-scale cancer genome studies in tumours from 50 different cancer types and/or subtypes that are of clinical and societal importance across the globe. Systematic studies of more than 25,000 cancer genomes at the genomic, epigenomic and transcriptomic levels will reveal the repertoire of oncogenic mutations, uncover traces of the mutagenic influences, define clinically relevant subtypes for prognosis and therapeutic management, and enable the development of new cancer therapies.
2,041 citations
Harvard University1, Boston University2, University of California, Davis3, Pompeu Fabra University4, Stony Brook University5, World Health Organization6, Katholieke Universiteit Leuven7, St George's Hospital8, University of Ibadan9, University of Tokyo10, The Chinese University of Hong Kong11, University of Paris12, University of Groningen13, All India Institute of Medical Sciences14, New Bulgarian University15, University of São Paulo16
TL;DR: In this paper, the authors examined joint associations of 12 childhood adversities with first onset of 20 DSM-IV disorders in World Mental Health Surveys in 21 countries and found strong associations with all classes of disorders at all life-course stages.
Abstract: Background
Although significant associations of childhood adversities with adult mental disorders are widely documented, most studies focus on single childhood adversities predicting single disorders.
Aims
To examine joint associations of 12 childhood adversities with first onset of 20 DSM–IV disorders in World Mental Health (WMH) Surveys in 21 countries.
Method
Nationally or regionally representative surveys of 51 945 adults assessed childhood adversities and lifetime DSM–IV disorders with the WHO Composite International Diagnostic Interview (CIDI).
Results
Childhood adversities were highly prevalent and interrelated. Childhood adversities associated with maladaptive family functioning (e.g. parental mental illness, child abuse, neglect) were the strongest predictors of disorders. Co-occurring childhood adversities associated with maladaptive family functioning had significant subadditive predictive associations and little specificity across disorders. Childhood adversities account for 29.8% of all disorders across countries.
Conclusions
Childhood adversities have strong associations with all classes of disorders at all life-course stages in all groups of WMH countries. Long-term associations imply the existence of as-yet undetermined mediators.
1,837 citations
Harvard University1, State University of New York System2, Nagoya City University3, University College Hospital, Ibadan4, The Chinese University of Hong Kong5, University of Michigan6, University of Cape Town7, University of Tasmania8, All India Institute of Medical Sciences9, University of São Paulo10
TL;DR: In this paper, the authors reported on the background and performance of the K6 screening scale for serious mental illness (SMI) in the World Health Organization (WHO) World Mental Health (WMH) surveys.
Abstract: Data are reported on the background and performance of the K6 screening scale for serious mental illness (SMI) in the World Health Organization (WHO) World Mental Health (WMH) surveys. The K6 is a six-item scale developed to provide a brief valid screen for Diagnostic and Statistical Manual of Mental Disorders 4th edition (DSM-IV) SMI based on the criteria in the US ADAMHA Reorganization Act. Although methodological studies have documented good K6 validity in a number of countries, optimal scoring rules have never been proposed. Such rules are presented here based on analysis of K6 data in nationally or regionally representative WMH surveys in 14 countries (combined N = 41,770 respondents). Twelve-month prevalence of DSM-IV SMI was assessed with the fully-structured WHO Composite International Diagnostic Interview. Nested logistic regression analysis was used to generate estimates of the predicted probability of SMI for each respondent from K6 scores, taking into consideration the possibility of variable concordance as a function of respondent age, gender, education, and country. Concordance, assessed by calculating the area under the receiver operating characteristic curve, was generally substantial (median 0.83; range 0.76-0.89; inter-quartile range 0.81-0.85). Based on this result, optimal scaling rules are presented for use by investigators working with the K6 scale in the countries studied.
1,408 citations
TL;DR: A review of the existing entrepreneurship literature that employs institutional theory to understand the current status of the field, its current shortcomings, and where we need to move in the future can be found in this article.
Abstract: Institutional theory is an increasingly utilized theoretical lens for entrepreneurship research. However, while institutional theory has proven highly useful, its use has reached a point that there is a need to establish a clearer understanding of its wide-ranging application to entrepreneurship research. Therefore, we will initially review the existing entrepreneurship literature that employs institutional theory to both understand the current status of the field, its current shortcomings, and where we need to move in the future. We then summarize and discuss the articles in this special issue and how they contribute to this process of advancing institutional theory and its application in entrepreneurship research.
1,206 citations
TL;DR: Transient elastography is accurate in most NAFLD patients and is useful as a screening test to exclude advanced fibrosis, and liver biopsy may be considered in patients with liver stiffness of at least 7.9 kPa.
1,101 citations
05 Sep 2010
TL;DR: It is found that strong edges do not always profit kernel estimation, but instead under certain circumstance degrade it, which leads to a new metric to measure the usefulness of image edges in motion deblurring and a gradient selection process to mitigate their possible adverse effect.
Abstract: We discuss a few new motion deblurring problems that are significant to kernel estimation and non-blind deconvolution. We found that strong edges do not always profit kernel estimation, but instead under certain circumstance degrade it. This finding leads to a new metric to measure the usefulness of image edges in motion deblurring and a gradient selection process to mitigate their possible adverse effect. We also propose an efficient and high-quality kernel estimation method based on using the spatial prior and the iterative support detection (ISD) kernel refinement, which avoids hard threshold of the kernel elements to enforce sparsity. We employ the TV-l1 deconvolution model, solved with a new variable substitution scheme to robustly suppress noise.
1,056 citations
TL;DR: The nth-order LDP is proposed to encode the (n-1)th -order local derivative direction variations, which can capture more detailed information than the first-order local pattern used in local binary pattern (LBP).
Abstract: This paper proposes a novel high-order local pattern descriptor, local derivative pattern (LDP), for face recognition. LDP is a general framework to encode directional pattern features based on local derivative variations. The nth-order LDP is proposed to encode the (n-1)th -order local derivative direction variations, which can capture more detailed information than the first-order local pattern used in local binary pattern (LBP). Different from LBP encoding the relationship between the central point and its neighbors, the LDP templates extract high-order local information by encoding various distinctive spatial relationships contained in a given local region. Both gray-level images and Gabor feature images are used to evaluate the comparative performances of LDP and LBP. Extensive experimental results on FERET, CAS-PEAL, CMU-PIE, Extended Yale B, and FRGC databases show that the high-order LDP consistently performs much better than LBP for both face identification and face verification under various conditions.
996 citations
TL;DR: Using high-throughput FISH analyses in both cell lines and in patients with lung cancer, the potential to prospectively identify treatment naive, patients with EGFR-mutant lung cancer who will benefit from initial combination therapy is highlighted.
TL;DR: This study shows that sequencing of maternal plasma DNA provides a way for noninvasive prenatal genome- wide scanning for genetic disorders and suggests the feasibility of using genome-wide scanning to diagnose fetal genetic disorders prenatally in a noninvasively way.
Abstract: Cell-free fetal DNA is present in the plasma of pregnant women. It consists of short DNA fragments among primarily maternally derived DNA fragments. We sequenced a maternal plasma DNA sample at up to 65-fold genomic coverage. We showed that the entire fetal and maternal genomes were represented in maternal plasma at a constant relative proportion. Plasma DNA molecules showed a predictable fragmentation pattern reminiscent of nuclease-cleaved nucleosomes, with the fetal DNA showing a reduction in a 166-base pair (bp) peak relative to a 143-bp peak, when compared with maternal DNA. We constructed a genome-wide genetic map and determined the mutational status of the fetus from the maternal plasma DNA sequences and from information about the paternal genotype and maternal haplotype. Our study suggests the feasibility of using genome-wide scanning to diagnose fetal genetic disorders prenatally in a noninvasive way.
TL;DR: A high level of linkage disequilibrium in the soybean genome is identified, suggesting that marker-assisted breeding of soybean will be less challenging than map-based cloning and to facilitate future breeding and quantitative trait analysis.
Abstract: We report a large-scale analysis of the patterns of genome-wide genetic variation in soybeans. We re-sequenced a total of 17 wild and 14 cultivated soybean genomes to an average of approximately ×5 depth and >90% coverage using the Illumina Genome Analyzer II platform. We compared the patterns of genetic variation between wild and cultivated soybeans and identified higher allelic diversity in wild soybeans. We identified a high level of linkage disequilibrium in the soybean genome, suggesting that marker-assisted breeding of soybean will be less challenging than map-based cloning. We report linkage disequilibrium block location and distribution, and we identified a set of 205,614 tag SNPs that may be useful for QTL mapping and association studies. The data here provide a valuable resource for the analysis of wild soybeans and to facilitate future breeding and quantitative trait analysis.
The Chinese University of Hong Kong1, University of Pittsburgh2, Pontifícia Universidade Católica do Rio Grande do Sul3, Sanjay Gandhi Post Graduate Institute of Medical Sciences4, University of Queensland5, Leiden University Medical Center6, University of Missouri7, Boston Children's Hospital8, University of Amsterdam9
TL;DR: In this article, the authors presented the results of a study at the University of Medicine and Therapeutics of the Chinese University of Hong Kong, Hong Kong and University of Pittsburgh School of Medicine.
Abstract: Department of Medicine and Therapeutics,1 Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong; University of Pittsburgh School of Medicine,2 Pittsburgh, PA, USA; Faculdade de Enfermagem, Nutrição e Fisioterapia,3 Pontifícia Universidade Católica do Rio Grande do Sul, Brazil; Sanjay Gandhi Postgraduate Institute of Medical Sciences,4 Lucknow, India; Department of Nephrology,5 Princess Alexandra Hospital, and School of Medicine, University of Queensland, Brisbane, Australia; Department of Medical Microbiology,6 Leiden University Medical Center, Leiden, The Netherlands; Centre for Kidney Diseases,7 Mount Elizabeth Medical Centre, Singapore; Section of Infectious Disease,8 Department of Internal Medicine, University of Missouri-Columbia School of Medicine, Columbia, MO, USA; Pediatric Nephrology Division,9 University Children’s Hospital, Heidelberg, Germany; Dianet Dialysis Centers,10 Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
TL;DR: In this article, the properties of the structure functions and other small-scale quantities in turbulent Rayleigh-Benard convection are reviewed from an experimental, theoretical, and numerical point of view.
Abstract: The properties of the structure functions and other small-scale quantities in turbulent Rayleigh-Benard convection are reviewed, from an experimental, theoretical, and numerical point of view. In particular, we address the question of whether, and if so where in the flow, the so-called Bolgiano-Obukhov scaling exists, i.e., Sθ(r) ∼ r2/5 for the second-order temperature structure function and Su(r) ∼ r6/5 for the second-order velocity structure function. Apart from the anisotropy and inhomogeneity of the flow, insufficiently high Rayleigh numbers, and intermittency corrections (which all hinder the identification of such a potential regime), there are also reasons, as a matter of principle, why such a scaling regime may be limited to at most a decade, namely the lack of clear scale separation between the Bolgiano length scale LB and the height of the cell.
TL;DR: GTWR was compared with global ordinary least squares, TWR, and GWR in terms of goodness-of-fit and other statistical measures using a case study of residential housing sales in the city of Calgary, Canada, from 2002 to 2004 and showed substantial benefits in modeling both spatial and temporal nonstationarity simultaneously.
Abstract: By incorporating temporal effects into the geographically weighted regression (GWR) model, an extended GWR model, geographically and temporally weighted regression (GTWR), has been developed to deal with both spatial and temporal nonstationarity simultaneously in real estate market data. Unlike the standard GWR model, GTWR integrates both temporal and spatial information in the weighting matrices to capture spatial and temporal heterogeneity. The GTWR design embodies a local weighting scheme wherein GWR and temporally weighted regression (TWR) become special cases of GTWR. In order to test its improved performance, GTWR was compared with global ordinary least squares, TWR, and GWR in terms of goodness-of-fit and other statistical measures using a case study of residential housing sales in the city of Calgary, Canada, from 2002 to 2004. The results showed that there were substantial benefits in modeling both spatial and temporal nonstationarity simultaneously. In the test sample, the TWR, GWR, and GTWR models, respectively, reduced absolute errors by 3.5%, 31.5%, and 46.4% relative to a global ordinary least squares model. More impressively, the GTWR model demonstrated a better goodness-of-fit (0.9282) than the TWR model (0.7794) and the GWR model (0.8897). McNamara's test supported the hypothesis that the improvements made by GTWR over the TWR and GWR models are statistically significant for the sample data.
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TL;DR: National strategies to raise public awareness about the disease and to improve standard of care and implementation of programmes for primary prevention are urgently needed to reduce the economic burden due to diabetes at personal, societal, and national levels.
TL;DR: Evidence for genetic selection at the EPAS1 locus from the GWADS study is supported by the replicated studies associating function with the allelic variants.
Abstract: By impairing both function and survival, the severe reduction in oxygen availability associated with high-altitude environments is likely to act as an agent of natural selection. We used genomic and candidate gene approaches to search for evidence of such genetic selection. First, a genome-wide allelic differentiation scan (GWADS) comparing indigenous highlanders of the Tibetan Plateau (3,200-3,500 m) with closely related lowland Han revealed a genome-wide significant divergence across eight SNPs located near EPAS1. This gene encodes the transcription factor HIF2alpha, which stimulates production of red blood cells and thus increases the concentration of hemoglobin in blood. Second, in a separate cohort of Tibetans residing at 4,200 m, we identified 31 EPAS1 SNPs in high linkage disequilibrium that correlated significantly with hemoglobin concentration. The sex-adjusted hemoglobin concentration was, on average, 0.8 g/dL lower in the major allele homozygotes compared with the heterozygotes. These findings were replicated in a third cohort of Tibetans residing at 4,300 m. The alleles associating with lower hemoglobin concentrations were correlated with the signal from the GWADS study and were observed at greatly elevated frequencies in the Tibetan cohorts compared with the Han. High hemoglobin concentrations are a cardinal feature of chronic mountain sickness offering one plausible mechanism for selection. Alternatively, as EPAS1 is pleiotropic in its effects, selection may have operated on some other aspect of the phenotype. Whichever of these explanations is correct, the evidence for genetic selection at the EPAS1 locus from the GWADS study is supported by the replicated studies associating function with the allelic variants.
TL;DR: An overview of the current evidence-base is provided focusing predominantly on three main questions: which, if any, of the commonly used anthropometric measures to define excess weight is more strongly associated with cardiovascular risk?
Abstract: Overweight and obesity have become a major public health problem in both developing and developed countries as they are causally related to a wide spectrum of chronic diseases including type II diabetes, cardiovascular diseases and cancer. However, uncertainty regarding the most appropriate means by which to define excess body weight remains. Traditionally, body mass index (BMI) has been the most widely used method by which to determine the prevalence of overweight in, and across, populations as well as an individual's level of risk. However, in recent years, measures of central obesity, principally waist circumference and the waist:hip ratio and to a lesser extent the waist:height ratio, which more accurately describe the distribution of body fat compared with BMI, have been suggested to be more closely associated with subsequent morbidity and mortality. There is also uncertainty about how these measures perform across diverse ethnic groups; earlier, most of the evidence regarding the relationships between excess weight and risk has been derived chiefly from Caucasian populations, and hence, it remains unclear whether the relationships are consistent in non-Caucasian populations. The purpose of this review, therefore, is to provide an overview of the current evidence-base focusing predominantly on three main questions: (1) Which, if any, of the commonly used anthropometric measures to define excess weight is more strongly associated with cardiovascular risk? (2) Which of the anthropometric measures is a better discriminator of risk? and (3) Are there any notable differences in the strength and nature of these associations across diverse ethnic groups?
TL;DR: Li et al. as mentioned in this paper found that abnormal related sales are not entirely accrual-based but can be cash-based as well, and they serve as a substitute rather than complement to accruals management for meeting earnings targets.
Abstract: Based on a sample of Chinese listed firms from 1998 through 2002, this paper documents that listed firms prop up earnings by using abnormal related sales to their controlling owners. Such related sales propping is more prevalent among state-owned firms and in regions with weaker economic institutions. We also find that these abnormal related sales are not entirely accrual-based but can be cash-based as well, and they serve as a substitute rather than complement to accruals management for meeting earnings targets. Since these abnormal related sales can be cash-based, there is significant cash transfer via related lending from listed firms back to controlling owners after the propping. However, no cash transfer via related lending is found to be associated with accruals earnings management.
University of Glasgow1, University of Oxford2, University of Texas Health Science Center at San Antonio3, Novartis4, Moscow State University5, University of North Carolina at Chapel Hill6, University College Cork7, Federal University of São Paulo8, National Taiwan University9, Centre Hospitalier Universitaire de Nantes10, The Chinese University of Hong Kong11, University of Leicester12, University of California, Berkeley13, University of Bern14, Tulane University15, Royal North Shore Hospital16, Medical University of Warsaw17, Harvard University18, Istanbul University19, University of Tromsø20, University of Washington21, Alfred Hospital22, University of Toronto23, University of Cape Town24, Cordoba University25, University of Illinois at Chicago26, Lahey Hospital & Medical Center27, University Medical Center Utrecht28, Umeå University29, Dresden University of Technology30, University of Liège31, Aarhus University32, Cardiovascular Institute of the South33, University of Copenhagen34, Semmelweis University35, University of Helsinki36, Duke University37
TL;DR: Among patients with impaired glucose tolerance and cardiovascular disease or risk factors, the use of valsartan for 5 years, along with lifestyle modification, led to a relative reduction of 14% in the incidence of diabetes but did not reduce the rate of cardiovascular events.
Abstract: BACKGROUND: It is not known whether drugs that block the renin-angiotensin system reduce the risk of diabetes and cardiovascular events in patients with impaired glucose tolerance. METHODS: In this double-blind, randomized clinical trial with a 2-by-2 factorial design, we assigned 9306 patients with impaired glucose tolerance and established cardiovascular disease or cardiovascular risk factors to receive valsartan (up to 160 mg daily) or placebo (and nateglinide or placebo) in addition to lifestyle modification. We then followed the patients for a median of 5.0 years for the development of diabetes (6.5 years for vital status). We studied the effects of valsartan on the occurrence of three coprimary outcomes: the development of diabetes; an extended composite outcome of death from cardiovascular causes, nonfatal myocardial infarction, nonfatal stroke, hospitalization for heart failure, arterial revascularization, or hospitalization for unstable angina; and a core composite outcome that excluded unstable angina and revascularization. RESULTS: The cumulative incidence of diabetes was 33.1% in the valsartan group, as compared with 36.8% in the placebo group (hazard ratio in the valsartan group, 0.86; 95% confidence interval [CI], 0.80 to 0.92; P<0.001). Valsartan, as compared with placebo, did not significantly reduce the incidence of either the extended cardiovascular outcome (14.5% vs. 14.8%; hazard ratio, 0.96; 95% CI, 0.86 to 1.07; P=0.43) or the core cardiovascular outcome (8.1% vs. 8.1%; hazard ratio, 0.99; 95% CI, 0.86 to 1.14; P=0.85). CONCLUSIONS: Among patients with impaired glucose tolerance and cardiovascular disease or risk factors, the use of valsartan for 5 years, along with lifestyle modification, led to a relative reduction of 14% in the incidence of diabetes but did not reduce the rate of cardiovascular events. (ClinicalTrials.gov number, NCT00097786.)
Harvard University1, Carlos III Health Institute2, University of São Paulo3, State University of New York System4, Katholieke Universiteit Leuven5, University of Paris6, The Chinese University of Hong Kong7, Pontifical University of the Holy Cross8, All India Institute of Medical Sciences9, New Bulgarian University10
TL;DR: An analysis of a large cross-national epidemiologic survey database that estimates the 12-month prevalence of suicidal behaviors, identifies risk factors for suicide attempts, and combines these factors to create a risk index for 12- month suicide attempts separately for developed and developing countries finds risk indices can predict suicide attempts with fairly good accuracy.
Abstract: Objective: Although suicide is a leading cause of death worldwide, clinicians and researchers lack a data-driven method to assess the risk of suicide attempts. This study reports the results of an analysis of a large cross-national epidemiologic survey database that estimates the 12-month prevalence of suicidal behaviors, identifies risk factors for suicide attempts, and combines these factors to create a risk index for 12-month suicide attempts separately for developed and developing countries. Method: Data come from the World Health Organization (WHO) World Mental Health (WMH) Surveys (conducted 2001–2007), in which 108,705 adults from 21 countries were interviewed using the WHO Composite International Diagnostic Interview. The survey assessed suicidal behaviors and potential risk factors across multiple domains, including sociodemographic characteristics, parent psychopathology, childhood adversities, DSM-IV disorders, and history of suicidal behavior. Results: Twelve-month prevalence estimates of suicide ideation, plans, and attempts are 2.0%, 0.6%, and 0.3%, respectively, for developed countries and 2.1%, 0.7%, and 0.4%, respectively, for developing countries. Risk factors for suicidal behaviors in both developed and developing countries include female sex, younger age, lower education and income, unmarried status, unemployment, parent psychopathology, childhood adversities, and presence of diverse 12-month DSMIV mental disorders. Combining risk factors from multiple domains produced risk indices that accurately predicted 12-month suicide attempts in both developed and developing countries (area under the receiver operating characteristic curve = 0.74–0.80). Conclusions: Suicidal behaviors occur at similar rates in both developed and developing countries. Risk indices assessing multiple domains can predict suicide attempts with fairly good accuracy and may be useful in aiding clinicians in the prediction of these behaviors.
TL;DR: Stalder et al. as discussed by the authors proposed a new method based on the Young-Laplace equation for measuring contact angles and surface tension, which can be used to measure axisymmetric sessile drops.
13 Jun 2010
TL;DR: In this article, a novel optical flow estimation method is proposed, which reduces the reliance of the flow estimates on their initial values propagated from the coarser level and enables recovering many motion details in each scale.
Abstract: We discuss the cause of a severe optical flow estimation problem that fine motion structures cannot always be correctly reconstructed in the commonly employed multi-scale variational framework. Our major finding is that significant and abrupt displacement transition wrecks small-scale motion structures in the coarse-to-fine refinement. A novel optical flow estimation method is proposed in this paper to address this issue, which reduces the reliance of the flow estimates on their initial values propagated from the coarser level and enables recovering many motion details in each scale. The contribution of this paper also includes adaption of the objective function and development of a new optimization procedure. The effectiveness of our method is borne out by experiments for both large- and small-displacement optical flow estimation.
TL;DR: This work provides a potential effective VLD photocatalyst to disinfect the bacterial cells, even to destruct the biofilm that can provide shelter and substratum for microorganisms and resist to disinfection.
Abstract: Urgent development of effective and low-cost disinfecting technologies is needed to address the problems caused by an outbreak of harmful microorganisms. In this work, we report an effective photocatalytic disinfection of E. coli K-12 by using a AgBr-Ag-Bi(2)WO(6) nanojunction system as a catalyst under visible light (lambda >or= 400 nm) irradiation. The visible-light-driven (VLD) AgBr-Ag-Bi(2)WO(6) nanojunction could completely inactivate 5 x 10(7) cfu mL(-1) E. coli K-12 within 15 min, which was superior to other VLD photocatalysts such as Bi(2)WO(6) superstructure, Ag-Bi(2)WO(6) and AgBr-Ag-TiO(2) composite. Moreover, the photochemical mechanism of bactericidal action for the AgBr-Ag-Bi(2)WO(6) nanojunction was investigated by using different scavengers. It was found that the diffusing hydroxyl radicals generated both by the oxidative pathway and the reductive pathway play an important role in the photocatalytic disinfection. Moreover, direct contact between the AgBr-Ag-Bi(2)WO(6) nanojunction and bacterial cells was not necessary for the photocatalytic disinfection of E. coli K-12. Finally, the photocatalytic destruction of the bacterial cells was directly observed by TEM images and further confirmed by the determination of potassium ion (K(+)) leakage from the killed bacteria. This work provides a potential effective VLD photocatalyst to disinfect the bacterial cells, even to destruct the biofilm that can provide shelter and substratum for microorganisms and resist to disinfection.
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TL;DR: This paper examined the influence of institutional environment on capital structure and debt maturity choices by examining a cross-section of firms in 39 developed and developing countries and found that firms in countries that are viewed as more corrupt tend to use less equity and more debt, especially short-term debt, while firms operating within legal systems that provide better protection for financial claimants tend to have capital structures with more equity, and relatively more longterm debt.
Abstract: This study examines the influence of institutional environment on capital structure and debt maturity choices by examining a cross-section of firms in 39 developed and developing countries. We find that a country's legal and tax system, the level of corruption and the preferences of capital suppliers explain a significant portion of the variation in leverage and debt maturity ratios. Our evidence indicate that firms in countries that are viewed as more corrupt tend to use less equity and more debt, especially short-term debt, while firms operating within legal systems that provide better protection for financial claimants tend to have capital structures with more equity, and relatively more long-term debt. In addition, the existence of an explicit bankruptcy code and/or deposit insurance is associated with higher leverage and more long-term debt. We also find that firms tend to use more debt in countries where there is a greater tax gain from leverage, while firms in countries with larger government bond markets have lower leverage, suggesting that government bonds tend to crowd out corporate debt. Countries with more extensive defined benefit pension funds have higher debt ratios and longer debt maturities, whereas those with more extensive defined contribution fund activities have lower debt ratios. In addition, debt ratios are lower in countries that limit the bond holdings of pension funds. Finally, we do not find a significant association between financing choices and the size of the insurance industry.
TL;DR: The occurrence of fracture of the subtrochanteric or diaphyseal femur was very rare, even among women who had been treated with bisphosphonates for as long as 10 years, and the study was underpowered for definitive conclusions.
Abstract: Background A number of recent case reports and series have identified a subgroup of atypical fractures of the femoral shaft associated with bisphosphonate use. A population-based study did not support this association. Such a relationship has not been examined in randomized trials. Methods We performed secondary analyses using the results of three large, randomized bisphosphonate trials: the Fracture Intervention Trial (FIT), the FIT Long-Term Extension (FLEX) trial, and the Health Outcomes and Reduced Incidence with Zoledronic Acid Once Yearly (HORIZON) Pivotal Fracture Trial (PFT). We reviewed fracture records and radiographs (when available) from all hip and femur fractures to identify those below the lesser trochanter and above the distal metaphyseal flare (subtrochanteric and diaphyseal femur fractures) and to assess atypical features. We calculated the relative hazards for subtrochanteric and diaphyseal fractures for each study. Results We reviewed 284 records for hip or femur fractures among 14,195...
TL;DR: Functional MSCs can be clonally generated, beginning at a single-cell level, from human iPSCs and can be prepared as an “off-the-shelf” format for the treatment of tissue ischemia.
Abstract: Background Aging and aging-related disorders impair the survival and differentiation potential of bone marrow mesenchymal stem cells (MSCs) and limit their therapeutic efficacy. Induced pluripotent stem cells (iPSCs) may provide an alternative source of functional MSCs for tissue repair. This study aimed to generate and characterize human iPSC-derived MSCs and to investigate their biological function for the treatment of limb ischemia. Methods and results Human iPSCs were induced to MSC differentiation with a clinically compliant protocol. Three monoclonal, karyotypically stable, and functional MSC-like cultures were successfully isolated using a combination of CD24(-) and CD105(+) sorting. They did not express pluripotent-associated markers but displayed MSC surface antigens and differentiated into adipocytes, osteocytes, and chondrocytes. Transplanting iPSC-MSCs into mice significantly attenuated severe hind-limb ischemia and promoted vascular and muscle regeneration. The benefits of iPSC-MSCs on limb ischemia were superior to those of adult bone marrow MSCs. The greater potential of iPSC-MSCs may be attributable to their superior survival and engraftment after transplantation to induce vascular and muscle regeneration via direct de novo differentiation and paracrine mechanisms. Conclusions Functional MSCs can be clonally generated, beginning at a single-cell level, from human iPSCs. Patient-specific iPSC-MSCs can be prepared as an "off-the-shelf" format for the treatment of tissue ischemia.
TL;DR: Although the diagnostic performance and the strength of the structure-function association were comparable between Cirrus HD-OCT and Stratus OCT RNFL measurements, Cirrus' measurement variability demonstrated lower measurement variability compared withstratus OCT with significant differences at 1, 3, 4, and 8 to 11 o'clock.
TL;DR: Co coating Au nanocrystals with semiconductor materials that have band gap energies smaller than the illumination laser energy can improve the photothermal conversion efficiency owing to the presence of an additional light absorption channel.
Abstract: Plasmon-based photothermal therapy is one of the most intriguing applications of noble metal nanostructures. The photothermal conversion efficiency is an essential parameter in practically realizing this application. The effects of the plasmon resonance wavelength, particle volume, shell coating, and assembly on the photothermal conversion efficiencies of Au nanocrystals are systematically studied by directly measuring the temperature of Au nanocrystal solutions with a thermocouple and analyzed on the basis of energy balance. The temperature of Au nanocrystal solutions reaches the maximum at ∼75 °C when the plasmon resonance wavelength of Au nanocrystals is equal to the illumination laser wavelength. For Au nanocrystals with similar shapes, the larger the nanocrystal, the smaller the photothermal conversion efficiency becomes. The photothermal conversion can also be controlled by shell coating and assembly through the change in the plasmon resonance energy of Au nanocrystals. Moreover, coating Au nanocrystals with semiconductor materials that have band gap energies smaller than the illumination laser energy can improve the photothermal conversion efficiency owing to the presence of an additional light absorption channel.