270 research outputs found

    Temporal variation in cave bear (Ursus spelaeus) dentition: The stratigraphic sequence of Scladina Cave, Belgium

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    © 2018 Elsevier Ltd The supposed herbivorous cave bear (Ursus spelaeus) occupied Europe throughout the Quaternary. Being subject to large spatial variation has led to the intensive study on its geographical polymorphism, generating debates on sub-speciation. However, temporal morphological information on the species is somewhat lacking. Here, we apply geometric morphometrics (GMM) technique to investigate temporal morphological variation in molar size and shape of Ursus spelaeus from different chronostratigraphic sediment units in a geographically confined site (Scladina Cave, Belgium), covering approximately 100,000 years. Our findings show significant morphological variation between groups analysed in both size and shape. M2 shows a chronological size increase with PCA plots visually expressing differences in all groups, relating to a buccolingual expansion and an increase of the talon masticatory platform through time. Reduction in the M1 is also shown, possibly to maintain biomechanical performance of dentition for effective mastication, more so in groups relating to the latter stages of the Quaternary. Findings suggest a rapid response to climatic factors constraining consumable food sources, with GMM offering a promising analytical approach in understanding the palaeobiology, palaeoecology and morphological variation in extinct and extant fossil mammals

    Peat swamp forest conservation withstands pervasive land conversion to oil palm plantation in North Selangor, Malaysia

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    Tropical deforestation remains one of the major global challenges of the twenty-first century driven to a large extent by the conversion of land for agricultural purposes, such as palm oil production. Malaysia is one of the world’s largest palm oil producers and has seen widespread conversion to oil palm from primary forest, including peat swamp forest (PSF). This study investigates the rate and extent of pervasive oil palm expansion in and around North Selangor Peat Swamp Forest (NSPSF) over the last three decades, exploring how land conversion has affected the region’s tropical forests, and assessing the relative success of PSF conservation measures. Time-series Landsat imagery was used to assess thematic land cover change and improvement in vegetation condition since NSPSF was given protected status in 1990. The results show a near tripling in oil palm cover throughout North Selangor, from 24,930 ha in 1989 to 70,070 ha in 2016; while at the same time tropical forest cover shrank from 145,570 ha to 88,400 ha. Despite concerns over the sustainability and environmental impact of such rapid oil palm conversion at a regional level, at the local scale, NSPSF represents a relative conservation success story. Effective land stewardship by government and non-governmental organization (NGO) management actors has limited illegal encroachment of oil palm around the reserve boundary. PSF rehabilitation measures have also markedly improved vegetation condition in NSPFS’s interior. These findings have broad significance for how oil palm agriculture is managed and especially for PSF stewardship and conservation, and the approaches described here may be usefully adopted elsewhere in Southeast Asia and around the world

    Scaling solutions from interacting fluids

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    We examine the dynamical implications of an interaction between some of the fluid components of the universe. We consider the combination of three matter components, one of which is a perfect fluid and the other two are interacting. The interaction term generalizes the cases found in scalar field cosmologies with an exponential potential. We find that attracting scaling solutions are obtained in several regions of parameter space, that oscillating behaviour is possible, and that new curvature scaling solutions exist. We also discuss the inflationary behaviour of the solutions and present some of the constraints on the strength of the coupling, namely those arising from nucleosynthesis.Comment: RevTeX, 21 pages, 8 figure

    A systematic screen for genes expressed in definitive endoderm by Serial Analysis of Gene Expression (SAGE)

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    BACKGROUND: The embryonic definitive endoderm (DE) gives rise to organs of the gastrointestinal and respiratory tract including the liver, pancreas and epithelia of the lung and colon. Understanding how DE progenitor cells generate these tissues is critical to understanding the cause of visceral organ disorders and cancers, and will ultimately lead to novel therapies including tissue and organ regeneration. However, investigation into the molecular mechanisms of DE differentiation has been hindered by the lack of early DE-specific markers. RESULTS: We describe the identification of novel as well as known genes that are expressed in DE using Serial Analysis of Gene Expression (SAGE). We generated and analyzed three longSAGE libraries from early DE of murine embryos: early whole definitive endoderm (0–6 somite stage), foregut (8–12 somite stage), and hindgut (8–12 somite stage). A list of candidate genes enriched for expression in endoderm was compiled through comparisons within these three endoderm libraries and against 133 mouse longSAGE libraries generated by the Mouse Atlas of Gene Expression Project encompassing multiple embryonic tissues and stages. Using whole mount in situ hybridization, we confirmed that 22/32 (69%) genes showed previously uncharacterized expression in the DE. Importantly, two genes identified, Pyy and 5730521E12Rik, showed exclusive DE expression at early stages of endoderm patterning. CONCLUSION: The high efficiency of this endoderm screen indicates that our approach can be successfully used to analyze and validate the vast amount of data obtained by the Mouse Atlas of Gene Expression Project. Importantly, these novel early endoderm-expressing genes will be valuable for further investigation into the molecular mechanisms that regulate endoderm development

    Identification of Equid herpesvirus 2 in tissue-engineered equine tendon

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    Background: Incidental findings of virus-like particles were identified following electron microscopy of tissue-engineered tendon constructs (TETC) derived from equine tenocytes. We set out to determine the nature of these particles, as there are few studies which identify virus in tendons per se, and their presence could have implications for tissue-engineering using allogenic grafts. Methods: Virus particles were identified in electron microscopy of TETCs. Virion morphology was used to initially hypothesise the virus identity.  Next generation sequencing was implemented to identify the virus. A pan herpesvirus PCR was used to validate the RNASeq findings using an independent platform. Histological analysis and biochemical analysis was undertaken on the TETCs. Results: Morphological features suggested the virus to be either a retrovirus or herpesvirus. Subsequent next generation sequencing mapped reads to Equid herpesvirus 2 (EHV2). Histological examination and biochemical testing for collagen content revealed no significant differences between virally affected TETCs and non-affected TETCs. An independent set of equine superficial digital flexor tendon tissue (n=10) examined using designed primers for specific EHV2 contigs identified at sequencing were negative. These data suggest that EHV is resident in some equine tendon. Conclusions: EHV2 was demonstrated in equine tenocytes for the first time; likely from in vivo infection. The presence of EHV2 could have implications to both tissue-engineering and tendinopathy

    Can international health programmes be sustained after the end of international funding? The case of eye care interventions in Ghana

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    There is general agreement amongst major international policy makers that sustainability is a key component of health interventions in developing countries. However, there is little evidence on the factors enabling or constraining sustainability. Diffusion of innovation theory can help explain how the continuation of activities is related to the attributes of innovations. Innovations are characterised by five attributes: (i) relative advantage; (ii) compatibility; (iii) complexity; (iv) triability; and (v) observability. An eye care programme was selected as a case study. The programme was implemented in the Brong Ahafo region of Ghana and had been funded over a ten-year period by an international organisation

    “There are things I want to say but you do not ask”: a comparison between standardised and individualised evaluations in substance use treatment

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    There has been an increasing call for service users to be more actively involved with the evaluation of treatment outcomes. One strategy to impove such involvement is to ask service users to contribute with their own criteria for evaluation by sharing their personal story and perspective about their clinical situation. In this cross-sectional study, we contrasted the contents elicited by service users completing two individualised measures against the contents of three widely used standardised measures. We also compared two methods to generate individualised data using self-report and interview-based instruments (PSYCHLOPS and PQ). Following a thematic comparison approach, we found that one quarter of the problems reported by patients in individualised measures were not covered by any of our standardised comparators. Also, half of our sample generated at least one problem whose theme was not covered by any of the three standardised measures. We also found that patients in this population have many other concerns beyond drug use. These included psychological (e.g. interpersonal relationships) and socio-economic (e.g. money) problems, which were frequently reported. Our study suggests that listening to service users’ stories allows us to capture issues of importance to service users in substance use treatment, which may be underestimated by standardised measures

    The impact of cardiovascular medication use on patients’ daily lives: a cross-sectional study

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    Introduction The management of multiple long-term medicines use in patients with chronic diseases creates a burden for patients. However, limited research is performed on patients’ experienced medication-related burden and its impact on daily lives. Therefore, the aim of this study was to explore the impact of cardiovascular medication on different aspects of patients’ daily lives and to examine the differences of these aspects between adherent and non-adherent patients. Methods A cross-sectional study was performed in two community pharmacies in the Netherlands. Patients (?45 years) using cardiovascular medication participated. Data were collected by means of the Living with Medicines Questionnaire (LMQ-2) measuring the burden of medicines use on patients’ daily lives. Two equally group-sized samples of patients non-adherent to prescribed medicines as assessed with pharmacy refill data, and patients adherent to prescribed medicines were selected. Results In total, 196 patients participated (51% male, 71.0±10.6 years), of whom 96 patients were non-adherent to cardiovascular medication. Substantial proportions of patients experienced medication-related burden on different daily life aspects. This burden was mainly related to the acceptance of long-term medication use, medication-related concerns or dissatisfaction, the interference of medicines with social and daily lives, and the interaction and communication with health care providers. No statistically significant results were found when comparing the impact on patients’ daily lives between the adherent and non-adherent sample. Conclusion Health care providers should acknowledge the impact of multiple long-term medicine use on patient’s daily lives and should make an effort to diminish patients’ medication-related burden by improving patient-provider relationships and by providing adequate treatment information incorporating patients’ individual circumstances and preferences. This may facilitate the integration of long-term medicines use in patients’ daily lives

    Interpreting ancient food practices:Stable isotope and molecular analyses of visible and absorbed residues from a year-long cooking experiment

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    Chemical analyses of carbonized and absorbed organic residues from archaeological ceramic cooking vessels can provide a unique window into the culinary cultures of ancient people, resource use, and environmental effects by identifying ingredients used in ancient meals. However, it remains uncertain whether recovered organic residues represent only the final foodstuffs prepared or are the accumulation of various cooking events within the same vessel. To assess this, we cooked seven mixtures of C3 and C4 foodstuffs in unglazed pots once per week for one year, then changed recipes between pots for the final cooking events. We conducted bulk stable-isotope analysis and lipid residue analysis on the charred food macro-remains, carbonized thin layer organic patina residues and absorbed lipids over the course of the experiment. Our results indicate that: (1) the composition of charred macro-remains represent the final foodstuffs cooked within vessels, (2) thin-layer patina residues represent a mixture of previous cooking events with bias towards the final product(s) cooked in the pot, and (3) absorbed lipid residues are developed over a number of cooking events and are replaced slowly over time, with little evidence of the final recipe ingredients

    Exploring the relationship between media coverage and participation in entrepreneurship : initial global evidence and research implications

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    Using a set of variables measured in the Global Entrepreneurship Monitor (GEM) study, our empirical investigation explored the influence of mass media through national culture on national entrepreneurial participation rates in 37 countries over 4 years (2000 to 2003). We found that stories about successful entrepreneurs, conveyed in mass media, were not significantly associated with the rate of nascent (opportunity searching) or the rate of actual (business activities commenced up to 3 months old) start-up activity, but that there was a significant positive association between the volume of entrepreneurship media stories and a nation&rsquo;s volume of people running a young business (that is in GEM terminology, a business aged greater than 3 but less than 42 months old). More particularly, such stories had strong positive association with opportunity oriented operators of young businesses. Together, these findings are compatible with what in the mass communications theory literature may be called the &lsquo;reinforcement model&rsquo;. This argues that mass media are only capable of reinforcing their audience&rsquo;s existing values and choice propensities but are not capable of shaping or changing those values and choices. In the area covered by this paper, policy-makers are committing public resources to media campaigns of doubtful utility in the absence of an evidence base. A main implication drawn from this study is the need for further and more sophisticated investigation into the relationship between media coverage of entrepreneurship, national culture and the rates and nature of people&rsquo;s participation in the various stages of the entrepreneurial process.<br /
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