Factors influencing the habitat use by ocelots in one of the last large Atlantic Forest remnants in southeastern Brazil

Ocelots (Leopardus pardalis) are widely distributed throughout the Americas, being dependent on forested areas to survive. Although ocelot ecology is broadly studied throughout the species range distribution, studies concerning factors that may affect ocelot occupancy in the Atlantic Forest are still scarce. We used camera traps to evaluate factors influencing the probabilities of detection and occupancy of ocelots in a protected area of the Atlantic Forest, the Rio Doce State Park (RDSP), southeastern Brazil. To assess ocelot occupancy and detection probabilities, we measured the distances between sampling stations and rivers, lakes, cities, pasture, and Eucalyptus plantations. In addition, we recorded the mean rainfall levels for each sampling occasion, and native grassland areas within a 500 m‐buffer around each sampling station. We found a strong and positive association between ocelot detection and the dry season, which might be due to a higher number of individuals moving through the Park during this season. Moreover, we found a strong and positive association of ocelot detection with native grassland areas around lakes, which may be related to the ocelot behavior of searching for prey in these areas. Conversely, the ocelot occupancy probability was intermediate (Ψ^ = 0.53, 95% CI = 0.36–0.69) and was not strongly associated with the evaluated covariates, which may be explained by the high‐quality of forest habitats and water resources that are homogeneously distributed within the Park. Our study indicates that the RDSP still provides a structurally suitable forest habitat for ocelots, but because of the current worrying scenario of over fragmentation, reduction of forest cover, and weakness of the protective legislation of this biome, the long‐term persistence of the species in RDSP is uncertain.     

Scorpionate-supported models of nickel-dependent superoxide dismutase

Ligation of nickel(II) by Trofimenko’s hydrotris(3,5-dimethyl-1-pyrazolyl)borate anion (Tp^Me,Me) and zwitterionic organoxanthate or dithiocarbamate co-ligands affords neutral high-spin pentacoordinate complexes with formally trianionic N₃S₂ ligand fields, similar to that of the nickel-dependent superoxide dismutase active site. Given this analogy to NiSOD, the structure, dynamics, and redox properties of the product complexes were examined. X-ray structures revealed rotation of the dithioacid chelates against the scorpionate face, giving coordination geometries between square pyramidal and trigonal bipyramidal limits. The complexes accordingly adopt paramagnetic (S = 1) d⁸ electron configurations, but magnetic susceptibilities suggest partial isomerization to a diamagnetic state in solution. The complexes also exhibit quasi-reversible one-electron redox couples at potentials suitable for SOD activity.     

Matched pairs in factorial experiments with binary data

Two more models are proposed for the analysis of matched pairs in factorial experiments with binary data. They are applied to two-period crossover designs. Estimation and test procedures are derived both approximately and by maximizing likelihoods. Comparisons are made with previous methods of analysis and between the models proposed.     

Meiotic sister chromatid exchanges are rare in C. elegans

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Identifying hotspots of molluscan species richness on rocky intertidal reefs

A significant question faced by environmental managers is how muchsurvey effort is required in order to obtain an accurate representation of thespecies richness in an area. The appropriateness of rapid survey techniques foridentifying biodiverse hotspots has not been previously tested for molluscs onintertidal rocky reefs. We used species inventories from standardized 4-h searchsurveys to rank 13 intertidal reefs in terms of their species richness and thesewere then compared to cumulative species records following repeated surveys fromthe same sites. A total of 172 surveys were conducted during low water springtides over a 3 year period, with up to 20 surveys at a single site.Species richness in the inventories varied from 20 to 94 on the different reefs.There was a strong correlation between the number of species recorded in thestandardized inventory and the total species richness from cumulative surveyrecords (r = 0.969; P < 0.001).Importantly, the total species diversity recorded at each site was not relatedto the number of surveys that were conducted at that site(r = 0.110; P = 0.784). This confirmsthat a single standardized timed search produces a useful representation ofmolluscan species richness. The majority of molluscs recorded in this study wereendemic to Australia (59%) and, significantly, the number of endemics waspositively correlated to the total species richness found at each site(r = 0.992; P < 0.0001). Our dataprovide clear evidence for a local hotspot of molluscan species richness andendemism on the northern side of Bass Point, Shellharbour. We suggest that on alocal scale biodiversity hotspots should only be identified as those sites thatcontain significantly more species than the local average. Two standarddeviations above the mean appears to be an appropriate cut-off for identifyinglocal biodiversity hotspots.     

Assessing New Zealand fern diversity from spatial predictions of species assemblages

The utility of explicit spatial predictions for biodiversity assessment is investigated with New Zealand fern flora. Distributions of 43 species were modelled from climatic and landform variables and predicted across New Zealand using generalised additive models (GAM). An original package of functions called generalised regression analysis and spatial prediction (GRASP) was developed to perform the analyses. On average, for the 43 models, the contributions of environmental variables indicate that mean annual temperature is the most important factor at this broad regional scale. Both annual solar radiation and its seasonality had higher correlations than temperature seasonality. Measures of water availability such as ratio of rainfall to potential evapotranspiration, air saturation deficit and soil water deficit presented significant contributions. Lithology was a better predictor than slope and drainage. These results are similar to those obtained from analyses of the distributions of New Zealand tree species and are consistent with the hypothesis that both tree and fern diversity are highest on sites conducive to high productivity. In order to identify hotspots of fern diversity, spatial predictions of individual species were summed up. The resulting map gave a very similar result to the direct prediction of their corresponding richness (number of species by plot out of 43 spp.). As a consequence, and where individual species models were not all available, the number of species within different species assemblages was directly modelled. Predicted richness hotspots of total species (out of 122 spp.), selected species (out of 43 and 21 spp.) and common species (out of 23 spp.) present very similar spatial patterns and are highly correlated. Richness of uncommon species (out of 39 spp.) was also accurately predicted, but presented a different spatial pattern. The number of rare species (out of 60 spp.) was not correctly modelled. Even though the lack of data for rare species clearly limits the application of this approach, fern community composition of more common species can be partially reconstructed from individual species predictions. This case study offers therefore a consistent approach not only for biodiversity hotspots identification, but also for setting targets to biodiversity assessment and restoration programs.     

Testing Hypotheses in the Two-period Change-over with Binary Data

The paper proposes a general model for analysizing two-period change-over designs with binary data. The model includes tests for carry-over effects, treatment and period effects in analogy to the well-known ANOVA-model for continuous data. Minimum modified χ²-statistics are derived and formulas for desk calculators are given.     

De novo mutation hotspots in homologous protein domains identify function-altering mutations in neurodevelopmental disorders

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