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61.
This paper analyzes the results of a survey that aims to explore World Bank project success factors and specifically the relationship between critical success factors (CSFs) and project success as perceived by World Bank Task Team Leaders (project supervisors). The exploratory factor analysis highlights a specific set of five CSFs: monitoring, coordination, design, training, and institutional environment. The regression analysis shows that there is a statistically significant and positive relationship between each of the five CSFs and project success. Consistent with theory and practice, the most prominent CSFs for project supervisors are design and monitoring. The findings contribute to the project CSF literature by conceptualizing project supervision as a multidimensional construct and by confirming supervision as a generic CSF for World Bank projects. The World Bank project supervisors and managers should strengthen project design and monitoring and thus improve project implementation as well as the chances for project success.  相似文献   
62.
OBJECTIVE: To measure the frequency and associated factors of cervicovaginal HIV shedding and to determine the impact of sexually transmitted disease (STD) treatment on HIV shedding. DESIGN: Cross-sectional study with 1-week follow-up. SETTING: Confidential clinic for female sex workers in Abidjan, C?te d'Ivoire. PARTICIPANTS: A total of 1201 female sex workers. INTERVENTIONS: STD treatment based on clinical signs. MAIN OUTCOME MEASURES: HIV serostatus; cervicovaginal HIV shedding at enrollment and at 1-week follow-up; STD status at enrollment and at 1-week follow-up. RESULTS: Cervicovaginal shedding of HIV-1 in HIV-1-seropositive women was more frequent (96 out of 404, 24%) than shedding of HIV-2 in HIV-2-seropositive women [one out of 21, 5%; odds ratio (OR), 6.2; 95% confidence interval (CI), 1.0-261]. Among 609 HIV-1-seropositive or dually seroreactive women, HIV-1 shedding was significantly more frequent in immunosuppressed women [adjusted OR (AOR), 6.3; 95% CI, 3.4-11.9; and AOR, 2.9; 95% CI, 1.6-5.0 for CD4 < 14% and CD4 14-28%, respectively, versus CD4 > 28%], and in women with Neisseria gonorrhoeae (AOR, 1.9; 95% CI, 1.2-3.0), those with Chlamydia trachomatis (AOR, 2.5; 95% CI, 1.1-5.8), and with a cervical or vaginal ulcer (AOR, 3.9; 95% CI, 2.1-7.4). HIV-1 shedding decreased from 42 to 21% (P < 0.005) in women whose STD were cured. CONCLUSIONS: These data help to explain the difference in transmissibility between HIV-1 and HIV-2 and the increased infectiousness of HIV in the presence of immunosuppression and STD. In addition, they lend biological plausibility to arguments for making STD control an integral part of HIV prevention strategies in Africa.  相似文献   
63.
Despite sequence similarity to SARS-CoV-1, SARS-CoV-2 has demonstrated greater widespread virulence and unique challenges to researchers aiming to study its pathogenicity in humans. The interaction of the viral receptor binding domain (RBD) with its main host cell receptor, angiotensin-converting enzyme 2 (ACE2), has emerged as a critical focal point for the development of anti-viral therapeutics and vaccines. In this study, we selectively identify and characterize the impact of mutating certain amino acid residues in the RBD of SARS-CoV-2 and in ACE2, by utilizing our recently developed NanoBiT technology-based biosensor as well as pseudotyped-virus infectivity assays. Specifically, we examine the mutational effects on RBD-ACE2 binding ability, efficacy of competitive inhibitors, as well as neutralizing antibody activity. We also look at the implications the mutations may have on virus transmissibility, host susceptibility, and the virus transmission path to humans. These critical determinants of virus–host interactions may provide more effective targets for ongoing vaccines, drug development, and potentially pave the way for determining the genetic variation underlying disease severity.  相似文献   
64.
Soil gas pollutants (VOCs, radon, …) have long been known to intrude into buildings through various openings, e.g., cracks and gaps in the foundations. As yet no model has been developed which can quantify this rate of flow whilst taking into account various substructure configurations. This is due to the complex phenomena that need to be consider and particularly to the difficulty in estimating pollutant flows at soil-building interfaces. In this paper analytical models have been developed to quantify these flows. The models have been developed for some typical substructure configurations: slab-on-grade, basement and crawlspace. The inputs of these models include particularly the foundation wall depth and the slab permeability. The analytical models have been compared to existing analytical models for one of the configurations. Moreover a 2-D finite element model has been used for numerical comparison. The models are presented as pressure-flow relationships and can be integrated into risk assessment tools in order to study the impact of soil gas pollutants on indoor air quality.  相似文献   
65.
To determine the origin and nature of mucinlike material in fine-needle aspiration (FNA) smears of the breast in noncancerous breast lesions, we studied breast FNA smears from four patients. All smears contained epithelial cells floating in a mucinlike background, which raised suspicion for mucinous (colloid) carcinoma. Mucicarmine stain was performed on one smear from each case. Subsequent tissue biopsy specimens were studied using mucicarmine, periodic acid-Schiff with and without diastase, and alcian blue stains at pH 2.7 and 0.9 on selected tissue sections. Correlation of the cytologic and histologic findings of each lesion was performed. The mucinlike background in all four FNA smears stained strongly with mucicarmine. Corresponding biopsy specimens revealed pseudoangiomatous hyperplasia in the first case, fibroadenoma and atypical ductal hyperplasia in the second, benign phyllodes tumor in the third, and fibroadenoma in the fourth. Each lesion in cases 1 to 3 was associated closely with fibrocystic changes. In case 4, cystic changes were located within the fibroadenoma. On tissue sections of all four cases, the cyst contents and 10% to 50% of normal lobule and duct contents stained with mucicarmine, indicating that the cyst contents were the most probable source of mucin in the FNA smears. The presence of pools of mucicarmine-positive material in FNA smears of the breast is not an exclusive feature of mucinous carcinoma; mucicarmine-positive mucin can arise from benign cystic changes as well as from normal lobules and ducts.  相似文献   
66.
This study shows markedly different isotype distributions of antibodies to asexual blood stages of Plasmodium falciparum and to merozoite surface protein 1 in clinically immune Senegalese adults depending on the study site. The relationships between immunoglobulin M (IgM) and IgG and between IgG3 and IgG1 antibodies differed in settings where transmission is perennial compared to settings where it is seasonal. This suggests a role for antibody class and/or subclass production and utilization in the regulation of protective immunity to such antigens.  相似文献   
67.
68.
Journal of Materials Science: Materials in Electronics - Nature provides a wide range of dielectric biopolymers that can be used in electronic devices. In this work, organic field-effect...  相似文献   
69.
This paper describes a comparative study allowing the selection of the most appropriate electric-propulsion system for a parallel hybrid electric vehicle (HEV). This paper is based on an exhaustive review of the state of the art and on an effective comparison of the performances of the four main electric-propulsion systems, namely the dc motor, the induction motor (IM), the permanent magnet synchronous motor, and the switched reluctance motor. The main conclusion drawn by the proposed comparative study is that it is the cage IM that better fulfills the major requirements of the HEV electric propulsion  相似文献   
70.
The biological problem of identifying the active genes during the cell division process is addressed. The cell division ensures the proliferation of cells, which is drastically aberrant in cancer cells. The studied genes are described by their expression profiles during the cell division cycle. Commonly, the identification process is a supervised approach based on an a priori set of reference genes, assumed as well-characterizing the cell cycle phases. Each studied gene is then classified by its peak similarity to one pre-specified reference gene. This classical approach suffers from two limitations. On the one hand, there is no consensus between biologists about the set of reference genes to consider for the identification process. On the other hand, the proximity measures used for genes expression profiles are unjustified and mainly based on the expression values regardless of the genes expression behavior. To identify genes expression profiles, a new adaptive clustering approach is proposed which consists of two main points. First, it allows in an unsupervised way the selection of a well-justified set of reference genes, to be compared with the pre-specified ones. Secondly, it enables the users to learn the appropriate proximity measure to use for genes expression data, a measure which will cover both proximity on values and on behavior. The adaptive clustering method is compared to a correlation-based approach through public and simulated genes expression data.  相似文献   
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