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Crocodilians are distributed widely through the tropics and subtropics, and several species pose a substantial threat to human life. This has important implications for human safety and crocodilian conservation. Understanding the drivers of crocodilian attacks on people could help minimize future attacks and inform conflict management. Crocodilian attacks follow a seasonal pattern in many regions, but there has been limited analysis of the relationship between attack occurrence and fine-scale contemporaneous environmental conditions. We use methods from environmental niche modelling to explore the relationships between attacks on people and abiotic predictors at a daily temporal resolution for the Nile crocodile Crocodylus niloticus in South Africa and Eswatini (formerly Swaziland), and the American alligator Alligator mississippiensis in Florida, USA. Our results indicate that ambient daily temperature is the most important abiotic temporal predictor of attack occurrence for both species, with attack likelihood increasing markedly when mean daily temperatures exceed 18 °C and peaking at 28 °C. It is likely that this relationship is explained partially by human propensity to spend time in and around water in warmer weather but also by the effect of temperature on crocodilian hunting behaviour and physiology, especially the ability to digest food. We discuss the potential of our findings to contribute to the management of crocodilians, with benefits for both human safety and conservation, and the application of environmental niche modelling for understanding human–wildlife conflicts involving both ectotherms and endotherms.
Conflicts with wildlife are a major challenge for conservation across Africa, and Nile crocodiles Crocodylus niloticus are allegedly responsible for more attacks on people than any other species; however, there is a lack of data regarding such attacks. We analysed reported attacks on people by Nile crocodiles in South Africa and eSwatini (Swaziland) during 1949–2016, identifying spatial and temporal patterns in attack incidence, as well as victim demographics. Through a literature review and archival searches we identified records of 214 attacks. Most attacks occurred in natural water bodies, with attacks in dams increasing since 2000. Most victims were attacked while swimming or bathing, others while fishing, doing domestic chores, and crossing waterways. There was a significant relationship between gender and activity when attacked. Children (< 16 years old) accounted for 51% of all attacks, with a higher fatality rate compared to adults. Most victims were male (65%), with teenage boys being the largest individual category. We make recommendations for conservation policy and management to mitigate attacks by Nile crocodiles.
Body dysmorphic disorder (BDD) has a significant impact on the patients’ quality of life (QOL). This is an initial literature review of QOL in patients with BDD, examining the extent of QOL impairments, the impact of psychiatric comorbidity on QOL, and the effect of treatment on QOL in BDD. Studies were identified through PubMed, MEDLINE, and PsycINFO searches from 1960–2011 using the keywords: “quality of life,” “body dysmorphic disorder,” “dysmorphophobia,” and “body image.” Studies included in this review were selected using specific criteria by two authors reaching consensus. Most BDD research studies have used symptom severity measures mainly to study BDD and its treatments. BBD with or without comorbidities is significantly associated with poor QOL and functioning. Studies show that treatment of BDD, either by psychopharmacological treatments such as selective serotonin reuptake inhibitors (SSRIs) or cognitive behavior therapy, might have positive effects on QOL, although these results need to be replicated in larger studies. In conclusion, QOL could add significant value to the assessment of BDD if used as one of the primary measures in research and clinical work in BDD, by providing more information and clearer understanding on the impact of the illness on satisfaction with activities of daily life and overall sense of wellbeing before and after treatment.
Most previous attempts to determine the psychological cost of military deployment have been limited by reliance on convenience samples, lack of pre-deployment data or confidentiality and cross-sectional designs.
This study addressed these limitations using a population-based, prospective cohort of US military personnel deployed in support of the operations in Iraq and Afghanistan.
The sample consisted of US military service members in all branches including active duty, reserve and national guard who deployed once (n = 3393) or multiple times (n = 4394). Self-reported symptoms of post-traumatic stress were obtained prior to deployment and at two follow-ups spaced 3 years apart. Data were examined for longitudinal trajectories using latent growth mixture modelling.
Each analysis revealed remarkably similar post-traumatic stress trajectories across time. The most common pattern was low–stable post-traumatic stress or resilience (83.1% single deployers, 84.9% multiple deployers), moderate–improving (8.0%, 8.5%), then worsening–chronic posttraumatic stress (6.7%, 4.5%), high–stable (2.2% single deployers only) and high–improving (2.2% multiple deployers only). Covariates associated with each trajectory were identified.
The final models exhibited similar types of trajectories for single and multiple deployers; most notably, the stable trajectory of low post-traumatic stress pre- to post-deployment, or resilience, was exceptionally high. Several factors predicting trajectories were identified, which we hope will assist in future research aimed at decreasing the risk of post-traumatic stress disorder among deployers.
The forests of western Amazonia support high site-level biological diversity, yet regional community heterogeneity is poorly understood. Using data from line transect surveys at 37 forest sites in south-eastern Peru, we assessed whether local primate assemblages are heterogeneous at the scale of a major watershed. We examined patterns of richness, abundance and community structure as a function of forest type, hunting pressure, land-management regime and geographic location. The primate assemblage composition and structure varied spatially across this relatively small region of Amazonia (≈ 85 000 km2), resulting from large-scale species patchiness rather than species turnover. Primate species richness varied among sites by a factor of two, community similarity by a factor of four and aggregate biomass by a factor of 45. Several environmental variables exhibited influence on community heterogeneity, though none as much as geographic location. Unflooded forest sites had higher species richness than floodplain forests, although neither numerical primate abundance nor aggregate biomass varied with forest type. Non-hunted sites safeguarded higher abundance and biomass, particularly of large-bodied species, than hunted sites. Spatial differences among species assemblages of a relatively generalist taxon like primates in this largely undisturbed forest region imply that community heterogeneity may be even greater in more species-rich taxa, as well as in regions of greater forest habitat diversity.
We studied the habitat use, activity patterns and use of mineral licks by five species of Amazonian ungulate using data from four 60-d camera trap surveys at two different sites in the lowland rain forest of Madre de Dios, Peru. Camera traps were set out in two regular grids with 40 and 43 camera stations covering an area of 50 and 65 km2, as well as at five mineral licks. Using occupancy analysis we tested the hypothesis that species are spatially separated. The results showed that the grey brocket deer (Mazama gouazoubira) occurred almost exclusively in terra firme forests, and that the white-lipped peccary (Tayassu pecari) used floodplain forest more frequently during some surveys. All other species showed no habitat preference and we did not find any spatial avoidance of species. The white-lipped peccary, the collared peccary (Pecari tajacu) as well as the grey brocket deer were strictly diurnal while the lowland tapir (Tapirus terrestris) was nocturnal. The red brocket deer (Mazama americana) was active day and night. The tapir was the species with the highest number of visits to mineral licks (average 52.8 visits per 100 d) followed by the white-lipped peccary (average 16.1 visits per 100 d) and the red brocket deer (average 17.1 visits per 100 d). The collared peccary was only recorded on three occasions and the grey brocket deer was never seen at a lick. Our results suggest that resource partitioning takes place mainly at the diet level and less at a spatial level; however, differences in small-scale habitat use are still possible.
Low dislocation density and even micropipe free substrates open up a great opportunity to produce high quality epitaxial layers. The epi-layer will become more sensitive to the epitaxial process itself and less dependent on varying substrate quality. Results presented here indicate a strong dependence of the epitaxial layers' growth mode and surface roughness on the substrates' dislocations and domain structure. Thick epitaxial layers grown on near on-axis wafers, both C-face and Si-face, show very similar growth behaviors as for physical vapor transport (PVT) grown crystals. The mix between step-flow and dislocation driven growth on near on-axis C-face chemical vapor deposition (CVD) grown epi-layers (30 μm thick) is resulting in a as smooth, and measured surface roughness is as low, as for growth on 8o off-axis substrates.
Surface roughness, Ra, measured on a 50 μm thick epitaxial layer, grown on a low EPD (1E+4 cm-2) 8o off-axis micropipe free substrate, was as low as 1.0 nm (2.98x2.32 mm area).
Comparative studies of election rules and legislative representation have focused intensively on vote–seat disproportionality as an indication of poor representation. Beginning with citizens' preferences, rather than votes, has important advantages and is especially more appropriate for a majoritarian vision of democracy. We analyse the effect of election rules on both vote–seat correspondence and median left–right correspondence in seventy elections in seventeen countries. We show theoretically the stringent conditions necessary to reduce vote–seat disproportionality in high threshold systems and empirically their high variance (and higher levels) of distortion. Although good median correspondence could be created, in theory, under a wide range of electoral systems, our empirical results suggest that proportional representation (PR) systems tend to outperform single-member district (SMD) systems by this criterion also.
We examined the influence of temperature and release density on the root-boring moth, Agapeta zoegana L., a biological control agent of diffuse knapweed, Centaurea diffusa Lam., and spotted knapweed, Centaurea maculosa Lam. Moths were released at six densities (1, 2, 4, 8, 16, and 32 adult male–female pairs) in each of 2 years (1992 and 1993 cohorts) into outdoor, caged plots containing spotted knapweed. Air temperature, larval establishment and mass, and adult emergence, mass, and body dimensions were measured. Larval production increased linearly with adult release density in both cohorts. Larval survival ranged from 0 to 100% and was not correlated with release density or accumulated degree-days in either year. Date of first emergence occurred earlier as both release density and larvae per plant increased, but only for the 1992 cohort. Declining resources or increased contact among the larvae may induce early pupation. Peak emergence rate increased with release density in both cohorts. First emergence was related more closely to calendar date than accumulated degree-days. In contrast, peak emergence rates were more consistent with degree-day accumulations between cohorts than calendar date. Adult production increased with parental release density in both cohorts. Females were heavier, wider, and longer than males. Optimal A. zoegana production will be achieved with releases of greater than 1.6 male–female adult pairs per spotted knapweed plant.
Cyphocleonus achates (Fahraeus) is a weevil used for the biological control of diffuse knapweed, Centaurea diffusa Monnet Del La Marck, and spotted knapweed, Centaurea maculosa Monnet Del La Marck, in North America. This research provided specific information on the biology of this insect in British Columbia. Adult weevils were released at six densities (1, 2, 4, 8, 16, and 32 male–female pairs) in each of 2 years into plots containing spotted knapweed. Larvae per plant, larval mass, larval survival, adult emergence, and air temperature were measured. Larval production increased with the release density of weevils in both the 1992 cohort and the 1993 cohort. Larval mass did not differ between years. Larval mass also did not vary with the release density of adults or the number of larvae per root. Larval survival of the 1993 cohort ranged from 17 to 48%, whereas that of the 1994 cohort ranged from 0 to 91%. Adult emergence began after the accumulation of 726–1144 degree-days. For both cohorts the date of first emergence occurred earlier, as the average number of larvae per plant increased for both cohorts. Increasing competition for food or space in the roots can induce early emergence. Sex ratios did not vary with date of emergence or release density of adult weevils. Adult emergence increased with the release density in the 1992 cohort, suggesting the average larval densities did not exceed the carrying capacity of the roots. The peak emergence rate increased with the release density in the 1992 cohort, but not in the 1993 cohort because of lower larval survival.
There is compelling evidence for the existence of susceptibility genes for bipolar disorder. Association studies using functional DNA variations are an important approach for identifying these genes. The enzyme catechol-O-methyltransferase (COMT) plays a key role in the degradation of catecholamine neurotransmitters and is a candidate for involvement in bipolar disorder. Recently a common functional genetic polymorphism that underlies population variation in COM Tactivity has been elucidated and a simple assay developed.
In a collaboration involving seven European centres, we have undertaken an association study of this functional polymorphism in 412 unrelated West European caucasian DSM - III-R bipolar patients and 368 ethnically matched controls.
We found no evidence of allelic or genotypic association.
We can conclude that variation at this functional polymorphism does not make an important contribution to bipolar disorder in the Western European population. Future studies using this powerful experimental approach can be expected to contribute to identification of bipolar susceptibility genes.
The feasibility of in situ coating of titania particles with silica using a high-temperature, gas-phase process was demonstrated. Titania was produced from the reaction of TiCl4 and O2 in a hot-wall, tubular, aerosol reactor and directly coated in the gas phase via the reaction of O2 with SiCl4 vapor. Rough SiO2 coatings were obtained at 1300 °C while uniform, dense coatings were obtained at all conditions examined for 1500 °C. The presence of water in the reactor significantly influenced the morphology of the coatings and resulted in smooth, dense, and uniform coatings at 1300 °C. Coating thicknesses could be controlled from 5 nm to roughly 100 nm, corresponding to growth rates on the order of 10–100 nmys. The characteristics of the coatings depended upon the concentration of SiCl4 and the coating temperature. These process variables influenced the coating mechanism, growth rate, and densification which directly influenced the coating uniformity and thickness.
We documented habitat use by the Resplendent Quetzal Pharomacrus mocinno, a large frugivorous bird that breeds in cloud-forests in the highlands of Central America, to assess the adequacy of protection afforded to regional biodiversity by the Monteverde reserve complex, a protected natural area that includes most of the highland forests of the Tilarán mountain range in western Costa Rica. Our results demonstrated that this relatively large (20,000 ha) protected natural area does not adequately protect the area's biodiversity. Through the use of radio-telemetry, we identified the areas on the Pacific slopes that are most critical to altirudinally migrating Quetzals. These forest patches are subject to deforestation and degradation and are rapidly becoming further isolated from other remaining forest. The possibility of the local extirpation of the Quetzal, through continued habitat loss on the Pacific slopes, presents an unusual dilemma for the region because the species is the major attraction for the Ideal tourist industry which now includes over 80 businesses and annually generates over US$5 million in local revenue. Therefore, its extirpation would seriously affect regional economic stability. In order to protect the Monteverde Quetzal population, we propose a regional conservation plan that depends on participation of local landowners to protect their remaining forest fragments and allows for the development of corridors to connect critical habitats as the focus of a regional conservation effort. While the ecological significance of the structure of corridors per se, versus other possible formats, is still being debated, we have selected the corridor format primarily because it is relatively easy for landowners to grasp the concept and the necessity for continuity of the corridor network. This recognition provides an important incentive for participation across property boundaries, promoting cooperation in a group effort rather than as isolated actions. Success of this cooperative plan will provide an example for grass-roots participation in buffer-zone management strategies elsewhere in the Neotropics.