171 research outputs found

    Tropical ancient DNA from bulk archaeological fish bone reveals the subsistence practices of a historic coastal community in southwest Madagascar

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    Taxonomic identification of archaeological fish bones provides important insights into the subsistence practices of ancient coastal peoples. However, it can be difficult to execute robust morphological identification of fish bones from species-rich fossil assemblages, especially from post-cranial material with few distinguishing features. Fragmentation, weathering and burning further impede taxonomic identification, resulting in large numbers of unidentifiable bones from archaeological sites. This limitation can be somewhat mitigated by taking an ancient DNA (aDNA) bulk-bone metabarcoding (BBM) approach to faunal identification, where DNA from non-diagnostic bone fragments is extracted and sequenced in parallel. However, a large proportion of fishing communities (both past and present) live in tropical regions that have sub-optimal conditions for long-term aDNA preservation. To date, the BBM method has never been applied to fish bones before, or to fossils excavated from an exposed context within a tropical climate. Here, we demonstrate that morphologically indistinct bulk fish bone from the tropics can be identified by sequencing aDNA extracted from 100 to 300 ya archaeological midden material in southwest Madagascar. Despite the biases of the approach, we rapidly obtained family, genus, and species-level assemblage information, and used this to describe a subset of the ichthyofauna exploited by an 18th century fishing community. We identified 23 families of fish, including benthic, pelagic, and coral-dwelling fishes, suggesting a reliance on a variety of marine and brackish habitats. When possible, BBM should be used alongside osteological approaches to address the limitations of both; however, this study highlights how genetic methods can nevertheless be a valuable tool for helping resolve faunal assemblages when morphological identification is hindered by taphonomic processes, lack of adequate comparative collections, and time constraints, and can provide a temporal perspective on fish biodiversity in the context of accelerated exploitation of the marine environment

    Determinants of enhanced risk disclosure of JSE top 40 companies : the board risk committee composition, frequency of meetings and the chief risk officer

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    Risk disclosure practices have received increasing attention in the wake of the 2008 global financial crisis. This study investigated possible determinants relating to the composition of the board committee responsible for risk management, the frequency of board risk committee meetings and whether the company employs a chief risk officer, which could manifest in an enhanced level of risk-related disclosure. Based on the possible determinants identified in the literature, nine hypotheses were developed in order to investigate which of these determinants relate to an enhanced level of risk disclosure by the selected companies. The first required integrated reports of non-financial companies in the Top 40 index of the JSE Securities Exchange were investigated in this study. Regarding one area of investigation, namely the level of risk management disclosure, it was found that the disclosure of companies whose risk committee met more frequently and the disclosure of companies that employed a chief risk officer, were of a relatively higher standard. With regard to the other area of investigation, namely the level of risk identification and mitigation disclosure, no clearly significant determinant of enhanced disclosure was identified.http://www.unisa.ac.za/default.asp?Cmd=ViewContent&ContentID=22335am2016Financial Managemen

    Metallothionein genes: no association with Crohn's disease in a New Zealand population

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    Metallothioneins (MTs) are excellent candidate genes for Inflammatory Bowel Disease (IBD) and have previously been shown to have altered expression in both animal and human studies of IBD. This is the first study to examine genetic variants within the MT genes and aims to determine whether such genetic variants have an important role in this disease. 28 tag SNPs in genes MT1 (subtypes A, B, E, F, G, H, M, X), MT2, MT3 and MT4 were selected for genotyping in a well-characterized New Zealand dataset consisting of 406 patients with Crohn's Disease and 638 controls. We did not find any evidence of association for MT genetic variation with CD. The lack of association indicates that genetic variants in the MT genes do not play a significant role in predisposing to CD in the New Zealand population

    Intramucosal adenocarcinoma of the ileum originated 40 years after ileosigmoidostomy

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    <p>Abstract</p> <p>Background</p> <p>Small bowel adenocarcinomas (SBAs) are rare carcinomas. They are asymptomatic and usually neither endoscopy nor contrast studies are performed for screening</p> <p>Case presentation</p> <p>A 72-year-old Japanese male had a positive fecal occult blood test at a regular check-up in 2006. He suffered appendicitis and received an ileosigmoidostomy in 1966. A colonoscopy revealed an irregular mucosal lesion with an unclear margin at the ileum side of the anastomosis. A mucosal biopsy specimen showed adenocarcinoma histopathologically. Excision of the anastomosis was performed for this patient. The resected specimen showed a flat mucosal lesion with a slight depression at the ileum adjacent to the anastomosis. Histological examination revealed a well differentiated intramucosal adenocarcinoma (adenocarcinoma in situ). Immunohistological staining demonstrated the overexpression of p53 protein in the adenocarcinoma.</p> <p>Conclusion</p> <p>Adenocarcinoma of the ileum at such an early stage is a very rare event. In this case, there is a possibility that the ileosigmoidostomy resulted in a back flow of colonic stool to the ileum that caused the carcinogenesis of the small intestine.</p

    Monovarietal extra-virgin olive oil classification: a fusion of human sensory attributes and an electronic tongue

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    Olive oil quality grading is traditionally assessed by human sensory evaluation of positive and negative attributes (olfactory, gustatory, and final olfactorygustatory sensations). However, it is not guaranteed that trained panelist can correctly classify monovarietal extra-virgin olive oils according to olive cultivar. In this work, the potential application of human (sensory panelists) and artificial (electronic tongue) sensory evaluation of olive oils was studied aiming to discriminate eight single-cultivar extra-virgin olive oils. Linear discriminant, partial least square discriminant, and sparse partial least square discriminant analyses were evaluated. The best predictive classification was obtained using linear discriminant analysis with simulated annealing selection algorithm. A low-level data fusion approach (18 electronic tongue signals and nine sensory attributes) enabled 100 % leave-one-out cross-validation correct classification, improving the discrimination capability of the individual use of sensor profiles or sensory attributes (70 and 57 % leave-one-out correct classifications, respectively). So, human sensory evaluation and electronic tongue analysis may be used as complementary tools allowing successful monovarietal olive oil discrimination.This work was co-financed by FCT/MEC and FEDER under Program PT2020 (Project UID/EQU/50020/2013); by Fundacao para a Ciencia e Tecnologia under the strategic funding of UID/BIO/04469/2013 unit; and by Project POCTEP through Project RED/AGROTEC-Experimentation network and transfer for development of agricultural and agro industrial sectors between Spain and Portugal

    Uptake of genetic testing by the children of Lynch syndrome variant carriers across three generations

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    Many Lynch syndrome (LS) carriers remain unidentified, thus missing early cancer detection and prevention opportunities. Tested probands should inform their relatives about cancer risk and options for genetic counselling and predictive gene testing, but many fail to undergo testing. To assess predictive testing uptake and demographic factors influencing this decision in LS families, a cross-sectional registry-based cohort study utilizing the Finnish Lynch syndrome registry was undertaken. Tested LS variant probands (1184) had 2068 children divided among three generations: 660 parents and 1324 children (first), 445 and 667 (second), and 79 and 77 (third). Of children aged 418 years, 801 (67.4%), 146 (43.2%), and 5 (23.8%), respectively, were genetically tested. Together, 539 first-generation LS variant carriers had 2068 children and grandchildren (3.84 per carrier). Of the 1548 (2.87 per carrier) eligible children, 952 (61.5%) were tested (1.77 per carrier). In multivariate models, age (OR 1.08 per year; 95% CI 1.06-1.10), family gene (OR 2.83; 1.75-4.57 for MLH1 and 2.59; 1.47-4.56 for MSH2 compared with MSH6), one or more tested siblings (OR 6.60; 4.82-9.03), no siblings (OR 4.63; 2.64-8.10), and parent under endoscopic surveillance (OR 5.22; 2.41-11.31) were independent predictors of having genetic testing. Examples of parental adherence to regular surveillance and genetically tested siblings strongly influenced children at 50% risk of LS to undergo predictive gene testing. High numbers of untested, adult at-risk individuals exist even among well-established cohorts of known LS families with good adherence to endoscopic surveillance.Peer reviewe

    Person-Related Protective and Vulnerability Factors of Psychopathology Symptoms in Non-Clinical Adolescents

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    Psychopathology in youths is thought to originate from a dynamic interplay of a variety of protective and vulnerability factors. In this study, a large multi-ethnic sample of non-clinical adolescents (N = 376) completed questionnaires for measuring a wide range of person-related protective and vulnerability factors as well as psychopathology symptoms, in order to explore (a) the relations among various protective and vulnerability factors, and (b) the unique contributions of these protective and vulnerability factors to different types of psychological problems. Results indicated that the overlap among protective and vulnerability factors was quite modest. Further, it was found that factors clustered in theoretically meaningful components reflecting protection, vulnerability, and more specific aspects of coping and social support. Finally, data indicated that each type of psychopathology symptoms was associated with a typical set of protective and vulnerability factors. Although these results should be interpreted with caution because of the cross-sectional nature of the study, they may nevertheless guide future research exploring multifactorial models of psychopathology in youths
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