1,660 research outputs found

    New and reemerging diseases: the importance of biomedical research.

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    A Computer Aided Detection system for mammographic images implemented on a GRID infrastructure

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    The use of an automatic system for the analysis of mammographic images has proven to be very useful to radiologists in the investigation of breast cancer, especially in the framework of mammographic-screening programs. A breast neoplasia is often marked by the presence of microcalcification clusters and massive lesions in the mammogram: hence the need for tools able to recognize such lesions at an early stage. In the framework of the GPCALMA (GRID Platform for Computer Assisted Library for MAmmography) project, the co-working of italian physicists and radiologists built a large distributed database of digitized mammographic images (about 5500 images corresponding to 1650 patients) and developed a CAD (Computer Aided Detection) system, able to make an automatic search of massive lesions and microcalcification clusters. The CAD is implemented in the GPCALMA integrated station, which can be used also for digitization, as archive and to perform statistical analyses. Some GPCALMA integrated stations have already been implemented and are currently on clinical trial in some italian hospitals. The emerging GRID technology can been used to connect the GPCALMA integrated stations operating in different medical centers. The GRID approach will support an effective tele- and co-working between radiologists, cancer specialists and epidemiology experts by allowing remote image analysis and interactive online diagnosis.Comment: 5 pages, 5 figures, to appear in the Proceedings of the 13th IEEE-NPSS Real Time Conference 2003, Montreal, Canada, May 18-23 200

    The determinants of Western Australia’s foreign investment in China

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    The growing economic importance of China with its major economic power in the East Asia region has become a popular host destination for receiving foreign investment from Hong Kong, Korea, and Taiwan. With China’s growth and development, this nation has over time become one of Australia’s main trading partners. As new investment opportunities have emerged, Australian companies, especially from Western Australia have shown interest in the Chinese marketplace. Despite the popular consensus that Australian companies are increasingly investing in China, to date relevant literature examining this notion is limited. Specifically, studies of elements that motivate or deter owners / managers of Australian companies, especially from Western Australia to invest in China are restricted. Consequently, the purpose of this study was to investigate the likely relationships between four independent constructs (1. market size, 2. labour cost, 3. infrastructure, and 4. business ethics) in China and the intensity of foreign investment from Western Australia, and to evaluate if and how these relationships are mediated by personality attributes (i.e., gender), organisational properties (i.e., size), and networking.To empirically investigate the determining factor for undertaking investment in China, this study employed both quantitative and qualitative approaches. The use of the quantitative method positivist approach is deemed as a suitable, partial approach, which assists in determining the statistical relationships between the investigated variables. Moreover, a qualitative approach was used in a complementing context to understand the quantitative results. Given the dynamic business environment in China, the use of a qualitative approach has potential for gaining a more comprehensive understanding of quantitative findings as well as providing rich information for further interpretations.This study was conducted with 43 respondents of Western Australian companies. A salient feature of the study companies is that they either have capabilities to invest or are already investing in mainland China (People’s Republic of China, in this study identified as China). The targeted companies are involved in manufacturing and services industries, such as mining, education, banking, and telecommunication. Although collecting primary data appeared to be a challenge, the data were robust for statistical analysis. In addition, the data were from decision makers of the study companies, which further indicate the richness of the sample.The findings of this study revealed that China’s large market size plays a positive role in attracting investments from WA to China. Similarly, the adequate level of infrastructure and the level of familiarity of business ethics in China tend to somewhat encourage WA investors to conduct business in China. In contrast, China’s cheap labour cost was not the primary driver that motivates WA companies to invest in China. In relation to the mediating effects of personality attributes (e.g., gender), organisational properties (i.e., size), and networking the study findings revealed that networking plays a significant mediating role in the investment decision. However, due to the relatively small sample size, personality attributes and organisational properties were established to provide insufficient analytical rigor in the decision to invest in China by WA companies.The implications for this study may offer insightful information to enrich the understanding of the determinants of Australian foreign investment in general, and in the Chinese marketplace in particular. In addition, by empirically investigating the perceptions of the decision makers of WA companies in relation to their investment decisions in China, the findings of this research may assist foreign companies to undertake better planning of their investment decisions. More specifically, this study may offer additional insight to those companies that are operating or planning to invest in the Chinese marketplace. For example, this study may be particularly useful for international managers or owners, as it may provide some fruitful information to assist a better understanding of the issues that relate to business ethics with Chinese operations. In addition, the phenomenon of guanxi in China has been considered as a major determinant for facilitating business engagement in the Chinese marketplace. It may, therefore, be argued that the phenomenon of guanxi in assisting business operations in China has become increasingly important, and international managers or owners may need to gain a deeper understanding of this phenomenon

    Portable CdTe detection system for mammographic X-ray spectroscopy

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    This paper describes a portable apparatus to be utilized in mammographic X-ray spectroscopy under clinical conditions. The system, based on a CdTe solid-state detector, is able to directly measure mammographic X-ray tube spectra. Good system response to monoenergetic photons was measured using X-ray and Îł-ray calibration sources (109Cd and 241Am). The measured molybdenum X-ray spectra, in agreement with simulated spectra, show the good spectral capability of the system also at high photon fluence rates, as typical of clinical mammography. Low tailing, no secondary X-ray escape and low pile-up distortions in the measured spectra indicate that this portable system is suitable for mammographic X-ray spectroscopy

    Towards a New System for the Assessment of the Quality in Care Pathways: An Overview of Systematic Reviews

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    Clinical or care pathways are developed by a multidisciplinary team of healthcare practitioners, based on clinical evidence, and standardized processes. The evaluation of their framework/content quality is unclear. The aim of this study was to describe which tools and domains are able to critically evaluate the quality of clinical/care pathways. An overview of systematic reviews was conducted, according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses, using Medline, Embase, Science Citation Index, PsychInfo, CINAHL, and Cochrane Library, from 2015 to 2020, and with snowballing methods. The quality of the reviews was assessed with Assessment the Methodology of Systematic Review (AMSTAR-2) and categorized with The Leuven Clinical Pathway Compass for the definition of the five domains: processes, service, clinical, team, and financial. We found nine reviews. Three achieved a high level of quality with AMSTAR-2. The areas classified according to The Leuven Clinical Pathway Compass were: 9.7% team multidisciplinary involvement, 13.2% clinical (morbidity/mortality), 44.3% process (continuity-clinical integration, transitional), 5.6% financial (length of stay), and 27.0% service (patient-/family-centered care). Overall, none of the 300 instruments retrieved could be considered a gold standard mainly because they did not cover all the critical pathway domains outlined by Leuven and Health Technology Assessment. This overview shows important insights for the definition of a multiprinciple framework of core domains for assessing the quality of pathways. The core domains should consider general critical aspects common to all pathways, but it is necessary to define specific domains for specific diseases, fast pathways, and adapting the tool to the cultural and organizational characteristics of the health system of each country

    Face Mask Use in the Community for Reducing the Spread of COVID-19: A Systematic Review

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    Background: Evidence is needed on the effectiveness of wearing face masks in the community to prevent SARS-CoV-2 transmission. / Methods: Systematic review and meta-analysis to investigate the efficacy and effectiveness of face mask use in a community setting and to predict the effectiveness of wearing a mask. We searched MEDLINE, EMBASE, SCISEARCH, The Cochrane Library, and pre-prints from inception to 22 April 2020 without restriction by language. We rated the certainty of evidence according to Cochrane and GRADE approach. / Findings: Our search identified 35 studies, including three randomized controlled trials (RCTs) (4,017 patients), 10 comparative studies (18,984 patients), 13 predictive models, nine laboratory experimental studies. For reducing infection rates, the estimates of cluster-RCTs were in favor of wearing face masks vs. no mask, but not at statistically significant levels (adjusted OR 0.90, 95% CI 0.78–1.05). Similar findings were reported in observational studies. Mathematical models indicated an important decrease in mortality when the population mask coverage is near-universal, regardless of mask efficacy. In the best-case scenario, when the mask efficacy is at 95%, the R0 can fall to 0.99 from an initial value of 16.90. Levels of mask filtration efficiency were heterogeneous, depending on the materials used (surgical mask: 45–97%). One laboratory study suggested a viral load reduction of 0.25 (95% CI 0.09–0.67) in favor of mask vs. no mask. / Interpretation: The findings of this systematic review and meta-analysis support the use of face masks in a community setting. Robust randomized trials on face mask effectiveness are needed to inform evidence-based policies. / PROSPERO registration: CRD42020184963

    The Bb fragment of complement factor B acts as a B cell growth factor.

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    The process of B cell growth and differentiation into plasma cells is highly regulated and may be influenced by a large number of inflammatory mediators, including complement components. We have studied the regulatory influence of Bb, a 60-kD peptide created during the cleavage of complement Factor B by Factor D and C3b. Purified Bb alone had no effect on proliferation and differentiation of human splenic or tonsillar B cells. However, when B cells were activated by Staphylococcus aureus Cowan I (SAC), Bb enhanced proliferation in a dose-dependent manner. Bb also enhanced proliferation when cocultured with SAC and suboptimal concentrations of purified 60-kD B cell growth factor (HMW-BCGF), a previously described lymphokine that is known to possess growth-promoting activity. However, Bb had no effect on cells treated with optimal concentrations of HMW-BCGF. Like HMW-BCGF, Bb's major effect was on the larger in vivo activated B cells. Half-maximal enhancement of proliferation was reached at a Bb concentration of 1-10 nM. Of note is the fact that antibody to Factor B recognized HMW-BCGF, and an mAb to HMW-BCGF also recognized Factor B and Bb, but not Ba. Moreover, radiolabeled Bb bound saturably to activated B cells and to an EBV-transformed human B cell line. The binding of Bb was inhibited by HMW-BCGF but not by Ba or IgG. Thus, Bb is antigenically and functionally related to HMW-BCGF, and can act as a B cell growth and differentiation factor at potentially physiologic concentrations. These data suggest that Bb may be important in amplifying the immune response in areas of inflammation. Since complement activation occurs at inflammatory sites long before induction of HMW-BCGF synthesis, Bb may be an early signal for the clonal expansion of antigen-activated B cells

    Face Mask Use in the Community for Reducing the Spread of COVID-19: A Systematic Review.

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    Background: Evidence is needed on the effectiveness of wearing face masks in the community to prevent SARS-CoV-2 transmission. Methods: Systematic review and meta-analysis to investigate the efficacy and effectiveness of face mask use in a community setting and to predict the effectiveness of wearing a mask. We searched MEDLINE, EMBASE, SCISEARCH, The Cochrane Library, and pre-prints from inception to 22 April 2020 without restriction by language. We rated the certainty of evidence according to Cochrane and GRADE approach. Findings: Our search identified 35 studies, including three randomized controlled trials (RCTs) (4,017 patients), 10 comparative studies (18,984 patients), 13 predictive models, nine laboratory experimental studies. For reducing infection rates, the estimates of cluster-RCTs were in favor of wearing face masks vs. no mask, but not at statistically significant levels (adjusted OR 0.90, 95% CI 0.78–1.05). Similar findings were reported in observational studies. Mathematical models indicated an important decrease in mortality when the population mask coverage is near-universal, regardless of mask efficacy. In the best-case scenario, when the mask efficacy is at 95%, the R0 can fall to 0.99 from an initial value of 16.90. Levels of mask filtration efficiency were heterogeneous, depending on the materials used (surgical mask: 45–97%). One laboratory study suggested a viral load reduction of 0.25 (95% CI 0.09–0.67) in favor of mask vs. no mask. Interpretation: The findings of this systematic review and meta-analysis support the use of face masks in a community setting. Robust randomized trials on face mask effectiveness are needed to inform evidence-based policies. PROSPERO registration: CRD42020184963
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