The status and behavioural ecology of large carnivores in a human-impacted miombo woodland

Decline in global carnivore populations has led to an increased demand for the assessment of carnivore densities in understudied habitats and the use of robust survey techniques to obtain these estimates. Furthermore, growing levels of anthropogenic disturbance can alter community structure and disrupt carnivore guild dynamics, thereby risking further population decline. This thesis examines the population status and intraguild dynamics of large carnivores in Kasungu National Park (KNP), Malawi. KNP is an example of a protected area that has experienced large-scale reductions in both carnivore and prey populations, whilst the miombo woodland of KNP has been identified as a habitat lacking baseline data on large carnivore density and behavioural ecology. Consequently, KNP is a novel site to 1) produce robust population estimates from an understudied habitat, and 2) improve understanding of niche partitioning strategies in a modified carnivore guild. Using the spotted hyaena (Crocuta crocuta) as a model species, Chapter Two reviews the current survey methodologies for estimating the population density of large carnivores. I advocate the wider application of spatial capture-recapture (SCR) techniques to estimate spotted hyaena density and provide recommendations for adopting these methods. In Chapter Three I provide a summary of the decline in protected area health and large carnivore populations in Malawi, before providing an overview of KNP and the sites’ importance to regional conservation efforts. I build on this in Chapter Four, using camera trap surveys and SCR modelling to estimate leopard (Panthera pardus) and spotted hyaena density in KNP between 2016 and 2018. Using a novel spatial partial identity model (SPIM), I also address the issue of uncertainty in individual identification from camera trap data. Density estimates were low across survey years, compared to estimates from sub-Saharan Africa, for both leopard (1.9 ±0.19 SD adults/100km2) and spotted hyaena (1.15 ±0.42 SD adults/100km2). In addition, the presence of lion (Panthera leo) and wild dog (Lycaon pictus) is limited to dispersing individuals, highlighting the degradation of the protected area and the wider loss to the carnivore guild in KNP. In Chapter Five, using a combination of co-detection modelling, time-to-event analyses, and temporal activity patterns from camera trap data, I examine the spatiotemporal dynamics of leopard and spotted hyaena in KNP. I find that detection of leopard and spotted hyaena is significantly associated with the detection of preferred prey and competing carnivores, increasing the likelihood of species interaction. In addition, female leopards display temporal partitioning from both intra- and inter-specific competitors, which may affect overall fitness and result in increased exposure to sources of anthropogenic mortality. Using scat analysis techniques, Chapter Six compares the dietary niche overlap, as a proxy for intraguild competition, of leopard and spotted hyaena in KNP. Results show that leopard and spotted hyaena share relatively high levels of dietary overlap (Pianka’s overlap = 0.65), providing further evidence of the potential for interspecific competition between the two species. This study provides the first robust population estimates for leopard and spotted hyaena in KNP and evidence of a range of niche partitioning strategies adopted by large carnivores in a modified carnivore guild. The low population density estimates for leopard and spotted hyaena are a cause for conservation concern. These concerns are exacerbated by the mutual drivers of spatiotemporal behaviour, the high levels of dietary overlap, and low prey densities, which increase the risk of exploitation and interference competition and could have negative consequences for population demographics. Therefore, increasing prey populations will be essential to minimise levels of interspecific competition between large carnivores. In addition, continued monitoring of population density and intraguild dynamics will be critical for assessing the efficacy of ongoing conservation initiatives in KNP and other protected areas in Malawi under similar levels of anthropogenic pressure

Using a model of group psychotherapy to support social research on sensitive topics

This article describes the exploratory use of professional therapeutic support by social researchers working on a sensitive topic. Talking to recently bereaved parents about the financial implications of their child's death was expected to be demanding work, and the research design included access to an independent psychotherapeutic service. Using this kind of professional support is rare within the general social research community, and it is useful to reflect on the process. There are likely to be implications for collection and interpretation of data, research output and the role and experience of the therapist. Here, the primary focus is the potential impact on researcher well-being

Signal processing with Levy information

Levy processes, which have stationary independent increments, are ideal for modelling the various types of noise that can arise in communication channels. If a Levy process admits exponential moments, then there exists a parametric family of measure changes called Esscher transformations. If the parameter is replaced with an independent random variable, the true value of which represents a "message", then under the transformed measure the original Levy process takes on the character of an "information process". In this paper we develop a theory of such Levy information processes. The underlying Levy process, which we call the fiducial process, represents the "noise type". Each such noise type is capable of carrying a message of a certain specification. A number of examples are worked out in detail, including information processes of the Brownian, Poisson, gamma, variance gamma, negative binomial, inverse Gaussian, and normal inverse Gaussian type. Although in general there is no additive decomposition of information into signal and noise, one is led nevertheless for each noise type to a well-defined scheme for signal detection and enhancement relevant to a variety of practical situations.Comment: 27 pages. Version to appear in: Proc. R. Soc. London

Integrated problem-based learning in the neuroscience curriculum – the SUNY Downstate experience

BACKGROUND: This paper reports the author's initial experience as Block Director in converting a Conventional Curriculum into a problem-based learning model (PBL) for teaching Psychopathology. As part of a wide initiative in curriculum reform, Psychopathology, which was a six-week course in the second-year medical school curriculum, became integrated into a combined Neuroscience block. The study compares curriculum conversion at State University of New York (SUNY), Downstate, with the experiences at other medical centres that have instituted similar curricula reform. METHODS: Student satisfaction with the Conventional and PBL components of the Neuroscience curriculum was compared using questionnaires and formal discussions between faculty and a body of elected students. The PBL experience in Psychopathology was also compared with that of the rest of the Neuroscience Block, which used large student groups and expert facilitators, while the Psychopathology track was limited to small groups using mentors differing widely in levels of expertise. RESULTS: Students appeared to indicate a preference toward conventional lectures and large PBL groups using expert facilitators in contrast to small group mentors who were not experts. Small PBL groups with expert mentors in the Psychopathology track were also rated favorably. CONCLUSION: The study reviews the advantages and pitfalls of the PBL system when applied to a Neuroscience curriculum on early career development. At SUNY, conversion from a Conventional model to a PBL model diverged from that proposed by Howard S. Barrows where student groups define the learning objectives and problem-solving strategies. In our model, the learning objectives were faculty-driven. The critical issue for the students appeared to be the level of faculty expertise rather than group size. Expert mentors were rated more favorably by students in fulfilling the philosophical objectives of PBL. The author, by citing the experience at other major Medical Faculties, makes a cautious attempt to address the challenges involved in the conversion of a Psychopathology curriculum into a PBL dominated format

Mining and analysis of audiology data to find significant factors associated with tinnitus masker

Objectives: The objective of this research is to find the factors associated with tinnitus masker from the literature, and by using the large amount of audiology data available from a large NHS (National Health Services, UK) hearing aid clinic. The factors evaluated were hearing impairment, age, gender, hearing aid type, mould and clinical comments. Design: The research includes literature survey for factors associated with tinnitus masker, and performs the analysis of audiology data using statistical and data mining techniques. Setting: This research uses a large audiology data but it also faced the problem of limited data for tinnitus. Participants: It uses 1,316 records for tinnitus and other diagnoses, and 10,437 records of clinical comments from a hearing aid clinic. Primary and secondary outcome measures: The research is looking for variables associated with tinnitus masker, and in future, these variables can be combined into a single model to develop a decision support system to predict about tinnitus masker for a patient. Results: The results demonstrated that tinnitus maskers are more likely to be fit to individuals with milder forms of hearing loss, and the factors age, gender, type of hearing aid and mould were all found significantly associated with tinnitus masker. In particular, those patients having Age<=55 years were more likely to wear a tinnitus masker, as well as those with milder forms of hearing loss. ITE (in the ear) hearing aids were also found associated with tinnitus masker. A feedback on the results of association of mould with tinnitus masker from a professional audiologist of a large NHS (National Health Services, UK) was also taken to better understand them. The results were obtained with different accuracy for different techniques. For example, the chi-squared test results were obtained with 95% accuracy, for Support and Confidence only those results were retained which had more than 1% Support and 80% Confidence. Conclusions: The variables audiograms, age, gender, hearing aid type and mould were found associated with the choice of tinnitus masker in the literature and by using statistical and data mining techniques. The further work in this research would lead to the development of a decision support system for tinnitus masker with an explanation that how that decision was obtained

Origin of the cataclysmic Late Heavy Bombardment period of the terrestrial planets

Nature, 435, pp. 466-469, http://dx.doi.org./10.1038/nature03676International audienc

Drug-resistant EGFR mutations promote lung cancer by stabilizing interfaces in ligand-free kinase-active EGFR oligomers

The Epidermal Growth Factor Receptor (EGFR) is frequently found to be mutated in non-small cell lung cancer. Oncogenic EGFR has been successfully targeted by tyrosine kinase inhibitors, but acquired drug resistance eventually overcomes the efficacy of these treatments. Attempts to surmount this therapeutic challenge are hindered by a poor understanding of how and why cancer mutations specifically amplify ligand-independent EGFR auto-phosphorylation signals to enhance cell survival and how this amplification is related to ligand-dependent cell proliferation. Here we show that drug-resistant EGFR mutations manipulate the assembly of ligand-free, kinase-active oligomers to promote and stabilize the assembly of oligomer-obligate active dimer sub-units and circumvent the need for ligand binding. We reveal the structure and assembly mechanisms of these ligand-free, kinase-active oligomers, uncovering oncogenic functions for hitherto orphan transmembrane and kinase interfaces, and for the ectodomain tethered conformation of EGFR. Importantly, we find that the active dimer sub-units within ligand-free oligomers are the high affinity binding sites competent to bind physiological ligand concentrations and thus drive tumor growth, revealing a link with tumor proliferation. Our findings provide a framework for future drug discovery directed at tackling oncogenic EGFR mutations by disabling oligomer-assembling interactions

Evaluating Active U: an Internet-mediated physical activity program.

Background: Engaging in regular physical activity can be challenging, particularly during the winter months. To promote physical activity at the University of Michigan during the winter months, an eight-week Internet-mediated program (Active U) was developed providing participants with an online physical activity log, goal setting, motivational emails, and optional team participation and competition. Methods: This study is a program evaluation of Active U. Approximately 47,000 faculty, staff, and graduate students were invited to participate in the online Active U intervention in the winter of 2007. Participants were assigned a physical activity goal and were asked to record each physical activity episode into the activity log for eight weeks. Statistics for program reach, effectiveness, adoption, and implementation were calculated using the Re-Aim framework. Multilevel regression analyses were used to assess the decline in rates of data entry and goal attainment during the program, to assess the likelihood of joining a team by demographic characteristics, to test the association between various predictors and the number of weeks an individual met his or her goal, and to analyze server load. Results: Overall, 7,483 individuals registered with the Active U website (≈16% of eligible), and 79% participated in the program by logging valid data at least once. Staff members, older participants, and those with a BMI < 25 were more likely to meet their weekly physical activity goals, and average rate of meeting goals was higher among participants who joined a competitive team compared to those who participated individually (IRR = 1.28, P < .001). Conclusion: Internet-mediated physical activity interventions that focus on physical activity logging and goal setting while incorporating team competition may help a significant percentage of the target population maintain their physical activity during the winter months