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The influence of large predators on the feeding ecology of two African mesocarnivores: the black-backed jackal and the brown hyaena
Interactions between apex and mesopredators and their impacts on prey populations have been well documented, while the influence of apex predators such as lions on carrion availability and the subsequent impacts at lower trophic levels are not fully understood. Here we assess dietary overlap between two sympatric carnivores (brown hyaena, Parahyaena brunnea, and black-backed jackal, Canis mesomelas) in neighbouring reserves with and without apex predators (lions, Panthera leo,and wild dog, Lycaon pictus). We investigate whether apex predators facilitate niche partitioning between mesocarnivores by creating additional scavenging opportunities through predatory activity. We found that brown hyaena density was higher in the area with apex predators, while black-backed jackal density was higher in the area without apex predators. Black-backed jackal scats contained broadly similar dietary items at both sites, while large mammal remains occurred significantly more frequently in brown hyaena scats collected inthe presence of apex predators. In the absence of apex predators there was a markedly higher degree of overlap between brown hyaena and jackal diets, suggesting increased levels of inter-specific competition. Our results suggest that apex predators potentially reduce levels of inter-specific competition for food between mesocarnivores by providing additional scavenging opportunities for specialist scavengers such as brown hyaena
The effects of paleoclimate on the distributions of some North West African Lizards.
As awareness grows regarding impacts of global climate change, so does concern over the effects these changes have on a species habitat and distribution. Climate change is thought to have a major effect on the distribution of species, with the potential to cause isolated/fragmented populations, which could lead to genetic divergence. In this study species distribution modelling was applied to species occurrence data on northwest African lizards from Morocco, with corresponding environmental data. The aim was to identify how intraspecific divergence might be related to historical climatic events. Species distribution models (SDMs) were used to quantify a species niche and define the constraining factors that affect that niche. SDMs predict areas of suitable habitat under different climatic scenarios that replicate prehistoric climates, and used to examine if there is evidence to suggest historical divergence or historical splits in distributions that correspond to current patterns of geographical divergence within species. MaxEnt was used to develop the SDMs and define the species niche and variable constraints. Previous studies have shown that the estimated divergence times of species discussed in this study range between 1–15 Ma. Environmental data dating back to these divergence times are unavailable or unreliable. Therefore, the Last Interglacial (LIG ~120,000 -140,000 years BP) and Last Glacial Maxima (LGM~ 21,000 years BP) datasets were used as a surrogate to earlier interglacial and glacial maximum climates, to analyse species distributions under earlier climatic scenarios which can then be inferred. The models produced from this study portray geographical fragmentation/isolations of suitable habitat between currently recognised subspecies for all species studied. The results from this study give insights into potential events that could cause intraspecific divergence. Given that glacial patterns occur in a cyclic manner during the Earth’s history, it is clear that they provide potential opportunities for disrupting a species habitat range and causing divergence due to oscillations between arid and humid environment
A live vaccine against Neospora caninum abortions in cattle
CommentaryMichael P. Reichel, Dadín P. Moore, Andrew Hemphill, Luis M. Ortega-Mora, J.P. Dubey, John T. Elli
Lack of Variation at Phosphoglucose Isomerase (Pgi) in Bumblebees: Implications for Conservation Genetics Studies
Assessing genetic variation underlying ecologically important traits is increasingly of interest and importance in population and conservation genetics. For some groups generally useful markers exist for examining the relative role of selection and drift in shaping genetic diversity e.g. the major histocompatibility complex in vertebrates and self-incompatibility loci in plants. For invertebrates there is no such generally useful locus. However, phosphoglucose isomerase (Pgi) has been proposed as a useful functional marker in the conservation genetics of invertebrates. Where thermal microclimate varies, balanced polymorphisms may be maintained due to trade-offs between thermally stable and kinetically advantageous allelic forms. We here report very low levels of Pgi variation in bumblebees rendering this locus to be of little use as an adaptive marker in a conservation genetics context in this group. Potential explanations for this lack of variation are considered
Robot computing for music visualization
© Springer Nature Switzerland AG 2019. This paper presents an algorithm design of Music Visualization on Robot (MVR) which could automatically link the flashlight, color, and emotion through music. We call this algorithm as MVR algorithm that composed by two analyses. First, we focus on Music Signal Analysis. Second, we focus on Music Sentiment Analysis. We integrate two analysis results and implement the MVR algorithm on a robot called Zenbo which is released from ASUS Company. We perform the Zenbo Robot in luminous environments. The MVR system not only could be used in Zenbo robot but also could extend to other fields of Artificial Intelligent (AI) equipment in the future
Chronic exposure of colorectal cancer cells to bevacizumab promotes compensatory pathways that mediate tumour cell migration
The gravitino coupling to broken gauge theories applied to the MSSM
We consider gravitino couplings in theories with broken gauge symmetries. In
particular, we compute the single gravitino production cross section in W+ W-
fusion processes. Despite recent claims to the contrary, we show that this
process is always subdominant to gluon fusion processes in the high energy
limit. The full calculation is performed numerically; however, we give analytic
expressions for the cross section in the supersymmetric and electroweak limits.
We also confirm these results with the use of the effective theory of goldstino
interactions.Comment: 26 pages, 4 figure
GPs' use of problem solving therapy for depression: a qualitative study of barriers to and enablers of evidence based care
BACKGROUND: Depression is a major health concern, predominantly treated by general practitioners (GPs). Problem solving therapy (PST) is recognised as an effective treatment for depression that is not widely used by GPs. This research aims to explore barriers and enablers that may influence GPs use of this treatment. METHOD: Qualitative methodology was used including individual and focus group interviews of GPs, PST experts and consumers. Analysis was undertaken using the Theory of Planned Behaviour (TPB) as a framework. RESULTS: A spectrum of potential influences, on GPs' use of PST emerged. Both barriers and enablers were identified. PST was perceived as being close to current practice approaches and potentially beneficial to both doctor and patient. In addition to a broadly positive attitude to PST, expressed by those with previous experience of its use, potential solutions to perceived barriers emerged. By contrast some GPs expressed fear that the use of PST would result in loss of doctor control of consultations and associated potential adverse patient outcomes. Patient expectations, which emerged as not always coinciding with GPs' perception of those expectations, were identified as a potential influence on GPs' decision concerning adoption of PST. In addition specific factors, including GP skill and confidence, consultation time constraints and technical issues related to PST were noted as potential concerns. CONCLUSION: This research contributes to our knowledge of the factors that may influence GPs' decisions regarding use of PST as a treatment for depression. It recognises both barriers and enablers. It suggests that for many GPs, PST is viewed in a positive light, providing encouragement to those seeking to increase the provision of PST by GPs. In identifying a number of potential barriers, along with associated options to address many of these barriers, it provides insights which may assist in the planning of GP training in PST
Controllable Photonic Time-Bin Qubits from a Quantum Dot
Photonic time bin qubits are well suited to transmission via optical fibres
and waveguide circuits. The states take the form , with and referring to
the early and late time bin respectively. By controlling the phase of a laser
driving a spin-flip Raman transition in a single-hole-charged InAs quantum dot
we demonstrate complete control over the phase, . We show that this
photon generation process can be performed deterministically, with only a
moderate loss in coherence. Finally, we encode different qubits in different
energies of the Raman scattered light, demonstrating wavelength division
multiplexing at the single photon level
Time to go global: a consultation on global health competencies for postgraduate doctors
BACKGROUND: Globalisation is having profound impacts on health and healthcare. We solicited the views of a wide range of stakeholders in order to develop core global health competencies for postgraduate doctors. METHODS: Published literature and existing curricula informed writing of seven global health competencies for consultation. A modified policy Delphi involved an online survey and face-to-face and telephone interviews over three rounds. RESULTS: Over 250 stakeholders participated, including doctors, other health professionals, policymakers and members of the public from all continents of the world. Participants indicated that global health competence is essential for postgraduate doctors and other health professionals. Concerns were expressed about overburdening curricula and identifying what is 'essential' for whom. Conflicting perspectives emerged about the importance and relevance of different global health topics. Five core competencies were developed: (1) diversity, human rights and ethics; (2) environmental, social and economic determinants of health; (3) global epidemiology; (4) global health governance; and (5) health systems and health professionals. CONCLUSIONS: Global health can bring important perspectives to postgraduate curricula, enhancing the ability of doctors to provide quality care. These global health competencies require tailoring to meet different trainees' needs and facilitate their incorporation into curricula. Healthcare and global health are ever-changing; therefore, the competencies will need to be regularly reviewed and updated
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