740 research outputs found
The need to conserve farm animal genetic resources through community-based management in Africa: Should policy makers be concerned?
This paper outlines some key factors contributing to the erosion of animal genetic resources and discusses strategic options for livestock sector policy makers to counter such erosion in their respective countries.The ratification of the Convention on Biological Diversity (CBD) in 1993 represents an international consensus to conserve biodiversity including that of farm animal and plant genetic resources, which are prerequisites for food security and the improvement of agricultural productivity. In Africa, conservation of agricultural biodiversity is inbuilt into the low input - low output production strategies of smallholder farming systems. These systems are often associated with poverty in rural areas and numerous development projects have thus sought to alleviate such poverty by promoting and subsidising crossbreeding or modern reproductive technologies. However, uncontrolled crossbreeding has been and remains a serious threat to the conservation of local farm animal populations. The primary policy goal for conservation of biodiversity should focus on the diversity between and within indigenous populations of farm animals. This includes, for example, the close monitoring of crossbreeding activities with exotic breeds. The genetic and phenotypic characterisation of local breeds is a prerequisite for this purpose. Economic valuation of biodiversity in general, of breeds within given production systems and an analysis of the social welfare implications of farm animal genetic resources (FAnGR) diversity conservation although relatively complex to carry out are also important for informed policy making. Despite the difficulties involved, objectives for the conservation of a local farm animal population and opportunities to utilise its diversity to meet present and future market demands, to serve as an insurance against environmental changes such as changes in production, socio-economic, historic and cultural conditions can be identified for research and development. To improve food security through the conservation of animal genetic resources in Africa, utilisation of local farm animal genetic resources depends on the ability of communities to decide on and implement appropriate breeding strategies. This cannot be realised without enabling policies. It is for this reason policy makers need to be concerned and should take action now
Mindfulness facets, trait emotional intelligence, emotional distress, and multiple health behaviors: A serial two-mediator model.
In the present study, we tested a serial mindfulness facets-trait emotional intelligence (TEI)-emotional distress-multiple health behaviors mediation model in a sample of N = 427 German-speaking occupational therapists. The mindfulness facets-TEI-emotional distress section of the mediation model revealed partial mediation for the mindfulness facets Act with awareness (Act/Aware) and Accept without judgment (Accept); inconsistent mediation was found for the Describe facet. The serial two-mediator model included three mediational pathways that may link each of the four mindfulness facets with multiple health behaviors. Eight out of 12 indirect effects reached significance and fully mediated the links between Act/Aware and Describe to multiple health behaviors; partial mediation was found for Accept. The mindfulness facet Observe was most relevant for multiple health behaviors, but its relation was not amenable to mediation. Implications of the findings will be discussed
Implicit prices of indigenous cattle traits in central Ethiopia: Application of revealed and stated preference approaches
The diversity of animal genetic resources has a quasi-public good nature that makes market prices inadequate indicator of its economic worth. Applying the characteristics theory of value, this research estimated the relative economic worth of the attributes of cattle genetic resources in central Ethiopia. Transaction level data were collected over four seasons in a year and choice experiment survey was done in five markets to generate data on both revealed and stated preferences of cattle buyers. Heteroscedasticity efficient estimation and
random parameters logit were employed to analyse the data. The results essentially show that attributes related to the subsistence functions of cattle are more valued than attributes that directly influence marketable products of the animals. The findings imply the strong need to invest on improvement of attributes of cattle in the study area that enhance the subsistence functions of cattle that their owners accord higher priority to support their livelihoods than they do to tradable products
Neurocognitive subgroups in major depressive disorder
Background: Major depressive disorder (MDD) is commonly associated with neurocognitive dysfunction. However, there remains substantial heterogeneity between patients and inconsistent findings regarding the magnitude and prevalence of specific neurocognitive deficits. This study aimed to investigate the potential for different neurocognitive subgroups in patients diagnosed with MDD. Method: Data were pooled from 4 different clinical trials that involved adults diagnosed with MDD. Neurocognitive outcomes included measures of verbal learning and memory, executive function, attention, and processing speed. Latent class analysis was conducted to examine for different subgroups based on neurocognitive profiles of performance across outcome measures. Subgroups were compared to a separate sample of age-matched adult healthy controls, across illness factors, and individual mood items on the Montgomery-Asberg Depression Rating Scale (MADRS). Results: Within the MDD cohort (N = 149), 45% of participants were considered relatively "cognitively preserved, " with the remainder "cognitively reduced" (39%) or "cognitively impaired" (16%). Verbal memory performance was significantly poorer compared to attention and processing speed only in the "cognitively impaired" subgroup. There was no association between subgroup membership and relevant illness factors, including ratings on individual MADRS items. Limitations: Data were pooled from several studies that included different neurocognitive measures and cohorts. Conclusions: Approximately half of MDD participants had no or minimal objective cognitive difficulties, and neurocognitive functioning was found generally unrelated to illness factors. Future longitudinal research is warranted to determine whether the people who are relatively cognitively impaired are at increased risk for further cognitive decline
Economic analysis of crossbreeding programmes in sub-Saharan Africa: A conceptual framework and Kenyan case study
Conventional economic evaluations of crossbreeding programmes have overestimated their benefits by ignoring subsidies, the increased costs of management such as veterinary support services, and the higher levels of risk and socio-environmental costs associated with the loss of the indigenous genotypes. A conceptual evaluation framework is developed and applied to Kenyan dairy farmers. Results suggest that at the national level crossbreeding has had a positive impact on Kenyan society's welfare, although taking into account important social cost components substantially lowers the net benefits. Farm-level performance is, however, little improved under certain production systems by replacing the indigenous zebu with exotic breeds
Inferring and perturbing cell fate regulomes in human brain organoids
Self-organizing neural organoids grown from pluripotent stem cells(1-3) combined with single-cell genomic technologies provide opportunities to examine gene regulatory networks underlying human brain development. Here we acquire single-cell transcriptome and accessible chromatin data over a dense time course in human organoids covering neuroepithelial formation, patterning, brain regionalization and neurogenesis, and identify temporally dynamic and brain-region-specific regulatory regions. We developed Pando-a flexible framework that incorporates multi-omic data and predictions of transcription-factor-binding sites to infer a global gene regulatory network describing organoid development. We use pooled genetic perturbation with single-cell transcriptome readout to assess transcription factor requirement for cell fate and state regulation in organoids. We find that certain factors regulate the abundance of cell fates, whereas other factors affect neuronal cell states after differentiation. We show that the transcription factor GLI3 is required for cortical fate establishment in humans, recapitulating previous research performed in mammalian model systems. We measure transcriptome and chromatin accessibility in normal or GLI3-perturbed cells and identify two distinct GLI3 regulomes that are central to telencephalic fate decisions: one regulating dorsoventral patterning with HES4/5 as direct GLI3 targets, and one controlling ganglionic eminence diversification later in development. Together, we provide a framework for how human model systems and single-cell technologies can be leveraged to reconstruct human developmental biology
Characterization of RNA content in individual phase-separated coacervate microdroplets
Condensates formed by complex coacervation are hypothesized to have played a crucial part during the origin-of-life. In living cells, condensation organizes biomolecules into a wide range of membraneless compartments. Although RNA is a key component of biological condensates and the central component of the RNA world hypothesis, little is known about what determines RNA accumulation in condensates and to which extend single condensates differ in their RNA composition. To address this, we developed an approach to read the RNA content from single synthetic and protein-based condensates using high-throughput sequencing. We find that certain RNAs efficiently accumulate in condensates. These RNAs are strongly enriched in sequence motifs which show high sequence similarity to short interspersed elements (SINEs). We observe similar results for protein-derived condensates, demonstrating applicability across different in vitro reconstituted membraneless organelles. Thus, our results provide a new inroad to explore the RNA content of phase-separated droplets at single condensate resolution
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