297 research outputs found
Comparison of a Novel Curvilinear Approach to Conventional Rectilinear Approach for Prostate Seed Implant
Purpose: To evaluate dosimetric benefit of curvilinear distribution of seeds for low-dose-rate (LDR) prostate brachytherapy with I-125 isotopes.
American Association of Physicists in Medicine (AAPM) 52nd Annual Meeting July 18-22, Philadelphia, P
Identifying Implementation Bugs in Machine Learning based Image Classifiers using Metamorphic Testing
We have recently witnessed tremendous success of Machine Learning (ML) in
practical applications. Computer vision, speech recognition and language
translation have all seen a near human level performance. We expect, in the
near future, most business applications will have some form of ML. However,
testing such applications is extremely challenging and would be very expensive
if we follow today's methodologies. In this work, we present an articulation of
the challenges in testing ML based applications. We then present our solution
approach, based on the concept of Metamorphic Testing, which aims to identify
implementation bugs in ML based image classifiers. We have developed
metamorphic relations for an application based on Support Vector Machine and a
Deep Learning based application. Empirical validation showed that our approach
was able to catch 71% of the implementation bugs in the ML applications.Comment: Published at 27th ACM SIGSOFT International Symposium on Software
Testing and Analysis (ISSTA 2018
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Exploring the prevalence of personality disorder and the feasibility of using the SAPAS as a screening tool for personality disorder in an emergency department in India
BACKGROUND: Personality disorders (PD) lead to frequent emergency department (ED) visits. Existing studies have evaluated high-risk ED populations in Western settings. PD screening tools, such as the Standardized Assessment of Personality - Abbreviated Scale (SAPAS), have thus far only been validated in Western populations.
AIMS: This study aimed to establish the screened prevalence of PD, and to evaluate the performance of the SAPAS as a screening tool within an ED setting in India.
METHODS: The study took place in the ED of a private multi-speciality hospital in Kolkata, India. All attendees were approached during two days per week over three months, except those who were medically unfit to participate. The SAPAS and the International Personality Disorder Examination (IPDE) were translated into Bengali and then used as screening tools for PD and as the reference standard for PD diagnosis.
RESULTS: Out of 120 ED attendees approached, 97 participated (48 men and 49 women), of whom 24% met the criteria for a diagnosis of PD. A cut-off score of 4 on the SAPAS provided the best trade-off between sensitivity and specificity for detecting PD.
CONCLUSION: The prevalence of PD was similar to Western samples, and the SAPAS showed promise for use in a non-Western setting
Coordination of myeloid differentiation with reduced cell cycle progression by PU.1 Induction of microRNAs targeting cell cycle regulators and lipid anabolism
During macrophage development, myeloid progenitor cells undergo terminal differentiation coordinated with reduced cell cycle progression. Differentiation of macrophages from myeloid progenitors is accompanied by increased expression of the E26 transformation-specific transcription factor PU.1. Reduced PU.1 expression leads to increased proliferation and impaired differentiation of myeloid progenitor cells. It is not understood how PU.1 coordinates macrophage differentiation with reduced cell cycle progression. In this study, we utilized cultured PU.1- inducible myeloid cells to perform genome-wide chromatin immunoprecipitation sequencing (ChIP-seq) analysis coupled with gene expression analysis to determine targets of PU.1 that may be involved in regulating cell cycle progression. We found that genes encoding cell cycle regulators and enzymes involved in lipid anabolism were directly and inducibly bound by PU.1 although their steady-state mRNA transcript levels were reduced. Inhibition of lipid anabolism was sufficient to reduce cell cycle progression in these cells. Induction of PU.1 reduced expression of E2f1, an important activator of genes involved in cell cycle and lipid anabolism, indirectly through microRNA 223. Next-generation sequencing identified microRNAs validated as targeting cell cycle and lipid anabolism for downregulation. These results suggest that PU.1 coordinates cell cycle progression with differentiation through induction of microRNAs targeting cell cycle regulators and lipid anabolism
Cluster of Nipah Virus Infection, Kushtia District, Bangladesh, 2007
OBJECTIVE: In March 2007, we investigated a cluster of Nipah encephalitis to identify risk factors for Nipah infection in Bangladesh. METHODS: We defined confirmed Nipah cases by the presence of IgM and IgG antibodies against Nipah virus in serum. Case-patients, who resided in the same village during the outbreak period but died before serum could be collected, were classified as probable cases. RESULTS: We identified three confirmed and five probable Nipah cases. There was a single index case. Five of the secondary cases came in close physical contact to the index case when she was ill. Case-patients were more likely to have physical contact with the index case (71% cases versus 0% controls, p = <0.001). The index case, on her third day of illness, and all the subsequent cases attended the same religious gathering. For three probable cases including the index case, we could not identify any known risk factors for Nipah infection such as physical contact with Nipah case-patients, consumption of raw date palm juice, or contact with sick animals or fruit bats. CONCLUSION: Though person-to-person transmission remains an important mode of transmission for Nipah infection, we could not confirm the source of infection for three of the probable Nipah case-patients. Continued surveillance and outbreak investigations will help better understand the transmission of Nipah virus and develop preventive strategies
Exploring the knowledge, awareness and practices of COVID-19 among dentists in Bangladesh: A Cross-sectional Investigation
Background: COVID-19 pandemic has caused an unpre-cedented strike on humanity around the world . The scenario in Bangladesh is getting worse day by day, and every aspect of the society is observing its impact. Health care professionals are at a greater risk of contracting the disease while caring for patients. Objective: The research objective is to explore knowledge, awareness, and practices of registered dentists regarding COVID-19 epidemiology and transmission during the rapid outbreak of this highly contagious virus in Bangladesh. Material and Methods: A cross-sectional web-based survey was conducted among the dentists who were enrolled with their valid unique Bangladesh Medical and Dental Council (BMDC) registration number. A structured questionnaire was distributed among the dentists through different social media platforms. A total of 184 dentists participated in the survey between March and April 2020. Both descriptive analysis and multivariable logistic regression analysis was performed. Results: The dentists' mean age was 31.75 years, with a standard deviation of 6.5 years. About 29.3% of dentists completed their postgraduate qualification, and 76% of them were engaged in private practice at the time of data collection. Compared to the dentists with undergraduate education, the dentists with a postgraduate education are three times (OR=3.1, 95%CI 1.2-7.9 and over 5 times (OR=5.3, 95% CI: 1.2-23.3) more likely to have) better knowledge and practices toward COVID-19 respectively. Dentists aged 26-30 years are less likely to have good practices than the younger dentists (OR: .1; 95% CI: .01-.5). However, dentists with less than five years experience are 10.3 (1.6-68.9) times more likely to have good practices compared to the dentists with more experience. Conclusion: Majority of the dentists from Bangladesh have shown good knowledge, awareness, and practice regarding COVID-19. We recommend that the healthcare authorities, professional organizations, and hospitals coordinate, and conduct mandatory advanced infectious disease training for all the practicing dentists in the country
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Nipah virus outbreak with person-to-person transmission in a district of Bangladesh, 2007
In February 2007 an outbreak of Nipah virus (NiV) encephalitis in Thakurgaon District of northwest Bangladesh affected seven people, three of whom died. All subsequent cases developed illness 7-14 days after close physical contact with the index case while he was ill. Cases were more likely than controls to have been in the same room (100% vs. 9.5%, OR undefined, P<0.001) and to have touched him (83% vs. 0%, OR undefined, P<0.001). Although the source of infection for the index case was not identified, 50% of Pteropus bats sampled from near the outbreak area 1 month after the outbreak had antibodies to NiV confirming the presence of the virus in the area. The outbreak was spread by person-to-person transmission. Risk of NiV infection in family caregivers highlights the need for infection control practices to limit transmission of potentially infectious body secretions
On the quest for selective constraints shaping the expressivity of the genes casting retropseudogenes in human
<p>Abstract</p> <p>Background</p> <p>Pseudogenes, the nonfunctional homologues of functional genes are now coming to light as important resources regarding the study of human protein evolution. Processed pseudogenes arising by reverse transcription and reinsertion can provide molecular record on the dynamics and evolution of genomes. Researches on the progenitors of human processed pseudogenes delved out their highly expressed and evolutionarily conserved characters. They are reported to be short and GC-poor indicating their high efficiency for retrotransposition. In this article we focused on their high expressivity and explored the factors contributing for that and their relevance in the milieu of protein sequence evolution.</p> <p>Results</p> <p>We here, analyzed the high expressivity of these genes configuring processed or retropseudogenes by their immense connectivity in protein-protein interaction network, an inclination towards alternative splicing mechanism, a lower rate of mRNA disintegration and a slower evolutionary rate. While the unusual trend of the upraised disorder in contrast with the high expressivity of the proteins encoded by processed pseudogene ancestors is accredited by a predominance of hub-protein encoding genes, a high propensity of repeat sequence containing genes, elevated protein stability and the functional constraint to perform the transcription regulatory jobs. Linear regression analysis demonstrates mRNA decay rate and protein intrinsic disorder as the influential factors controlling the expressivity of these retropseudogene ancestors while the latter one is found to have the most significant regulatory power.</p> <p>Conclusions</p> <p>Our findings imply that, the affluence of disordered regions elevating the network attachment to be involved in important cellular assignments and the stability in transcriptional level are acting as the prevailing forces behind the high expressivity of the human genes configuring processed pseudogenes.</p
Income redistribution in the European Union
We explore the redistributive effects of taxes and benefits in the 27 member states of the European Union (EU) using EUROMOD, the tax-benefit microsimulation model for the EU. As well as describing redistributive effects in aggregate, we assess and compare the effectiveness of eight individual types of policy in reducing income disparities. We derive results for the 27 members of the EU using policies in effect in 2010 and present them for each country separately as well as for the EU as a whole
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