309 research outputs found

    Relationships between farmer psychological profiles and farm business performance amongst smallholder beef and poultry farmers in South Africa

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    Beef cattle and poultry are critically important livestock for improving household food security and alleviating poverty amongst smallholder farmers in South Africa. In this paper, our goal is to examine the relationships between farmer psychological profiles and farm business performance of commercially oriented beef cattle and poultry smallholder farmers in South Africa. We employ a multipronged interdisciplinary approach to test the theory of planned behaviour and its relationship to farm business performance. First, a behavioural science-informed survey instrument was employed to collect data from randomly selected farmer participants in two major beef and poultry projects undertaken by the authors. Second, a latent profile analysis was used to identify the psychological profiles of those farmers. Third, traditional and estimated indicators of farm business performance were obtained using descriptive and econometric-based approaches, including logistic regression and stochastic frontier analyses. The estimated farm business performance indicators were correlated with the psychological profiles of farmers. Results from the latent profile analysis showed three distinct profiles of beef and poultry farmers clearly differentiated by their ability to control and succeed in their farm business enterprises; criteria included attitude, openness to ideas, personality, perceived capabilities, self-efficacy, time orientation, and farm- and personal-related concerns. Profile 1 (‘Fatalists’) scored themselves negatively on their ability to control and succeed in their business enterprises. The majority of farmers were generally neutral about their ability to control and succeed in their businesses (Profile 2, ‘Traditionalists’), while a relatively small group of farmers were confident of their ability to succeed (Profile 3, ‘Entrepreneurs’). We found evidence of significant differences in farm business performance amongst the different profiles of farmers. As far as we can determine, this is the only study to have assessed farm business performance based on a differentiation of farmers’ psychological profiles. Our results provide a framework to further investigate whether particular types of on-farm interventions and training methods can be customised for different segments of farmers based on their preferred learning styles

    Can organic agriculture contribute to sustainable development in the tropics?

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    Agricultural intensification over last decades has resulted in a great increase of crop yields, but it also had a detrimental impact on biodiversity. The dramatic decline of arable weed diversity is a matter of great concern because weeds have an important ecological function as a key component of the food web of agroecosystems. Weeds are suitable indicators of management effects on wildlife diversity in arable crops because they have high sensitivity to cultivation measures and have a strong relation to other organism groups. Nevertheless, the effect of farming management on weed abundance and diversity will be more reliable on weed seed bank rather than on aboveground weed community because it is the result of processes that have occurred in the past and consequently, it could better reflect the effect of the agricultural practices over the years

    Synchrotron imaging of dentition provides insights into the biology of Hesperornis and Ichthyornis, the "last" toothed birds.

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    BACKGROUND: The dentitions of extinct organisms can provide pivotal information regarding their phylogenetic position, as well as paleobiology, diet, development, and growth. Extant birds are edentulous (toothless), but their closest relatives among stem birds, the Cretaceous Hesperornithiformes and Ichthyornithiformes, retained teeth. Despite their significant phylogenetic position immediately outside the avian crown group, the dentitions of these taxa have never been studied in detail. To obtain new insight into the biology of these 'last' toothed birds, we use cutting-edge visualisation techniques to describe their dentitions at unprecedented levels of detail, in particular propagation phase contrast x-ray synchrotron microtomography at high-resolution. RESULTS: Among other characteristics of tooth shape, growth, attachment, implantation, replacement, and dental tissue microstructures, revealed by these analyses, we find that tooth morphology and ornamentation differ greatly between the Hesperornithiformes and Ichthyornithiformes. We also highlight the first Old World, and youngest record of the major Mesozoic clade Ichthyornithiformes. Both taxa exhibit extremely thin and simple enamel. The extension rate of Hesperornis tooth dentine appears relatively high compared to non-avian dinosaurs. Root attachment is found for the first time to be fully thecodont via gomphosis in both taxa, but in Hesperornis secondary evolution led to teeth implantation in a groove, at least locally without a periodontal ligament. Dental replacement is shown to be lingual via a resorption pit in the root, in both taxa. CONCLUSIONS: Our results allow comparison with other archosaurs and also mammals, with implications regarding dental character evolution across amniotes. Some dental features of the 'last' toothed birds can be interpreted as functional adaptations related to diet and mode of predation, while others appear to be products of their peculiar phylogenetic heritage. The autapomorphic Hesperornis groove might have favoured firmer root attachment. These observations highlight complexity in the evolutionary history of tooth reduction in the avian lineage and also clarify alleged avian dental characteristics in the frame of a long-standing debate on bird origins. Finally, new hypotheses emerge that will possibly be tested by further analyses of avian teeth, for instance regarding dental replacement rates, or simplification and thinning of enamel throughout the course of early avian evolution

    Morally distressing experiences, moral injury, and burnout in florida healthcare providers during the covid-19 pandemic

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    Because healthcare providers may be experiencing moral injury (MI), we inquired about their healthcare morally distressing experiences (HMDEs), MI perpetrated by self (Self MI) or others (Others MI), and burnout during the COVID-19 pandemic. Participants were 265 healthcare providers in North Central Florida (81.9% female, Mage = 37.62) recruited via flyers and emailed brochures that completed online surveys monthly for four months. Logistic regression analyses investigated whether MI was associated with specific HMDEs, risk factors (demographic characteristics, prior mental/medical health adversity, COVID-19 protection concern, health worry, and work impact), protective factors (personal resilience and leadership support), and psychiatric symptomatology (depression, anxiety, and PTSD). Linear regression analyses explored how Self/Others MI, psychiatric symptomatology, and the risk/protective factors related to burnout. We found consistently high rates of MI and burnout, and that both Self and Others MI were associated with specific HMDEs, COVID-19 work impact, COVID-19 protection concern, and leadership support. Others MI was also related to prior adversity, nurse role, COVID-19 health worry, and COVID-19 diagnosis. Predictors of burnout included Self MI, depression symptoms, COVID-19 work impact, and leadership support. Hospital administrators/supervisors should recognize the importance of supporting the HCPs they supervise, particularly those at greatest risk of MI and burnout

    Craniofacial development illuminates the evolution of nightbirds (Strisores)

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    Evolutionary variation in ontogeny played a central role in the origin of the avian skull. However, its influence in subsequent bird evolution is largely unexplored. We assess the links between ontogenetic and evolutionary variation of skull morphology in Strisores (nightbirds). Nightbirds span an exceptional range of ecologies, sizes, life-history traits and craniofacial morphologies constituting an ideal test for evo-devo hypotheses of avian craniofacial evolution. These morphologies include superficially 'juvenile-like' broad, flat skulls with short rostra and large orbits in swifts, nightjars and allied lineages, and the elongate, narrow rostra and globular skulls of hummingbirds. Here, we show that nightbird skulls undergo large ontogenetic shape changes that differ strongly from widespread avian patterns. While the superficially juvenile-like skull morphology of many adult nightbirds results from convergent evolution, rather than paedomorphosis, the divergent cranial morphology of hummingbirds originates from an evolutionary reversal to a more typical avian ontogenetic trajectory combined with accelerated ontogenetic shape change. Our findings underscore the evolutionary lability of cranial growth and development in birds, and the underappreciated role of this aspect of phenotypic variability in the macroevolutionary diversification of the amniote skull

    The Cyprinodon variegatus genome reveals gene expression changes underlying differences in skull morphology among closely related species

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    Genes in durophage intersection set at 15 dpf. This is a comma separated table of the genes in the 15 dpf durophage intersection set. Given are edgeR results for each pairwise comparison. Columns indicating whether a gene is included in the intersection set at a threshold of 1.5 or 2 fold are provided. (CSV 13 kb

    Development and Functional Analysis of Novel Genetic Promoters Using DNA Shuffling, Hybridization and a Combination Thereof

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    BACKGROUND: Development of novel synthetic promoters with enhanced regulatory activity is of great value for a diverse range of plant biotechnology applications. METHODOLOGY: Using the Figwort mosaic virus full-length transcript promoter (F) and the sub-genomic transcript promoter (FS) sequences, we generated two single shuffled promoter libraries (LssF and LssFS), two multiple shuffled promoter libraries (LmsFS-F and LmsF-FS), two hybrid promoters (FuasFScp and FSuasFcp) and two hybrid-shuffled promoter libraries (LhsFuasFScp and LhsFSuasFcp). Transient expression activities of approximately 50 shuffled promoter clones from each of these libraries were assayed in tobacco (Nicotiana tabacum cv. Xanthi) protoplasts. It was observed that most of the shuffled promoters showed reduced activity compared to the two parent promoters (F and FS) and the CaMV35S promoter. In silico studies (computer simulated analyses) revealed that the reduced promoter activities of the shuffled promoters could be due to their higher helical stability. On the contrary, the hybrid promoters FuasFScp and FSuasFcp showed enhanced activities compared to F, FS and CaMV 35S in both transient and transgenic Nicotiana tabacum and Arabidopsis plants. Northern-blot and qRT-PCR data revealed a positive correlation between transcription and enzymatic activity in transgenic tobacco plants expressing hybrid promoters. Histochemical/X-gluc staining of whole transgenic seedlings/tissue-sections and fluorescence images of ImaGene Greenâ„¢ treated roots and stems expressing the GUS reporter gene under the control of the FuasFScp and FSuasFcp promoters also support the above findings. Furthermore, protein extracts made from protoplasts expressing the human defensin (HNP-1) gene driven by hybrid promoters showed enhanced antibacterial activity compared to the CaMV35S promoter. SIGNIFICANCE/CONCLUSION: Both shuffled and hybrid promoters developed in the present study can be used as molecular tools to study the regulation of ectopic gene expression in plants

    Complete Ichthyornis skull illuminates mosaic assembly of the avian head

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    The skull of living birds is greatly modified from the condition found in their dinosaurian antecedents. Bird skulls have an enlarged, toothless premaxillary beak and an intricate kinetic system that includes a mobile palate and jaw suspensorium. The expanded avian neurocranium protects an enlarged brain and is flanked by reduced jaw adductor muscles. However, the order of appearance of these features and the nature of their earliest manifestations remain unknown. The Late Cretaceous toothed bird Ichthyornis dispar sits in a pivotal phylogenetic position outside living groups: it is close to the extant avian radiation but retains numerous ancestral characters 1-3. Although its evolutionary importance continues to be affirmed 3-8, no substantial new cranial material of I. dispar has been described beyond incomplete remains recovered in the 1870s. Jurassic and Cretaceous Lagerstatten have yielded important avialan fossils, but their skulls are typically crushed and distorted 9. Here we report four three-dimensionally preserved specimens of I. dispar- including an unusually complete skull-as well as two previously overlooked elements from the Yale Peabody Museum holotype, YPM 1450. We used these specimens to generate a nearly complete three-dimensional reconstruction of the I. dispar skull using highresolution computed tomography. Our study reveals that I. dispar had a transitional beak-small, lacking a palatal shelf and restricted to the tips of the jaws-coupled with a kinetic system similar to that of living birds. The feeding apparatus of extant birds therefore evolved earlier than previously thought and its components were functionally and developmentally coordinated. The brain was relatively modern, but the temporal region was unexpectedly dinosaurian: it retained a large adductor chamber bounded dorsally by substantial bony remnants of the ancestral reptilian upper temporal fenestra. This combination of features documents that important attributes of the avian brain and palate evolved before the reduction of jaw musculature and the full transformation of the beak. </p
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