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Today, digital multimedia (audio, video, images) is a common evidential source in litigation and criminal justice proceedings, and, not surprisingly, multimedia forensics is an active research area. One particular challenge faced by multimedia forensic researchers is the lack of a comprehensive and publicly available data-set for evaluating existing and new algorithms. This paper presents a digital audio forensic data-set, designed to facilitate evaluation of audio forensic algorithms (e.g. microphone identification, acoustic environment identification and splice detection). This paper also briefly describes the data-collection settings, microphones, speakers, languages and notations used. Existing tamper-detection techniques rely on artefacts due to recording devices, codec and/or the acoustic environment in the audio in question. Experimental results show that the selected approaches achieved promising results.  相似文献   
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Abstract

This study examined Type A and Type B differences in job performance, psychosomatic complaints, and career progression among white-collar employees (N = 218) in a field setting. Significant differences were found between Type A's and Type B's in quality of performance, effort exerted at the job, and psychosomatic complaints. Employees' cultural background and sex moderated some of the relationships observed in the study. Implications of the findings for future research on the topic are discussed.  相似文献   
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Kommerell’s diverticulum is a rare saccular aneurysmal dilation of the descending aorta. We report a case of a 3.5-year-old boy with the extremely rare combination of Kommerell’s diverticulum with a right descending aorta and proximal patent ductus arteriosus aneurysm forming an incomplete vascular ring. To our knowledge, this rare case has not been reported to date.  相似文献   
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Arsenic (As) is considered to be one of the top environmental contaminants of concern worldwide. In many regions in Pakistan, there are reports of increased levels of As in the environment, and this metalloid remains a major source of contamination of soil, water and fodder. This pathway of exposure has emerged as a new threat for both wildlife and the surrounding human communities because of the mobilization and accumulation of As via the food chain. The objective of this critical review is to synthesize historical information about As levels in the environmental resources of Pakistan to better characterize the risk to livestock and humans in the region. The South Punjab and Sindh are the dominant areas which are reported to contain the highest As contamination compared to other regions. This is a concern as millions of animals as well as the human population are facing significant health issues due to As. For example, some of the population of Sindh province are potentially faced with As levels ~10–50?μg/L in drinking water, which is well above safe drinking limits of 10?μg/L outlined by the World Health Organization. These collective data on As are anticipated to be a useful source of information for decisions by the environmental protection agency in Pakistan regarding the adoption of preventive measures against its adverse impacts and toxicity.  相似文献   
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