1,081 research outputs found

    Ownership-dependent mating tactics of minor males of the beetle Librodor japonicus (Nitidulidae) with intra-sexual dimorphism of mandibles

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    Intra-sexual dimorphism is found in the weapons of many male beetles. Different behavioral tactics to access females between major and minor males, which adopt fighting and alternative tactics, respectively, are thought to maintain the male dimorphism. In these species major males have enlarged weapons that they use in fights with rival males. Minor males also have small weapons in some of these species, and it is unclear why these males possess weapons. We examined the hypothesis that minor males might adopt a fighting tactic when their status was relatively high in comparison with that of other males (e.g., ownership of a territory). We observed the behavioral tactics of major and minor males of the beetle Librodor japonicus, whose males have a dimorphism of their mandibles. Major males fought for resources, whereas minor males adopted two status-dependent tactics, fighting and sneaking, to access females, depending on their ownership of a sap site. We suggest that ownership status-dependent mating tactics in minor males may maintain the intra-sexual dimorphism in this beetle.</p

    Locality Error Free Effective Core Potentials for 3d Transition Metal Elements Developed for the Diffusion Monte Carlo Method

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    Pseudopotential locality errors have hampered the applications of the diffusion Monte Carlo (DMC) method in materials containing transition metals, in particular oxides. We have developed locality error free effective core potentials, pseudo-Hamiltonians, for transition metals ranging from Cr to Zn. We have modified a procedure published by some of us in [M.C. Bennett et al, JCTC 18 (2022)]. We carefully optimized our pseudo-Hamiltonians and achieved transferability errors comparable to the best semilocal pseudopotentials used with DMC but without incurring in locality errors. Our pseudo-Hamiltonian set (named OPH23) bears the potential to significantly improve the accuracy of many-body-first-principles calculations in fundamental science research of complex materials involving transition metals

    Noncovalent Interactions by QMC: Speedup by One-Particle Basis-Set Size Reduction

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    While it is empirically accepted that the fixed-node diffusion Monte-Carlo (FN-DMC) depends only weakly on the size of the one-particle basis sets used to expand its guiding functions, limits of this observation are not settled yet. Our recent work indicates that under the FN error cancellation conditions, augmented triple zeta basis sets are sufficient to achieve a benchmark level of 0.1 kcal/mol in a number of small noncovalent complexes. Here we report on a possibility of truncation of the one-particle basis sets used in FN-DMC guiding functions that has no visible effect on the accuracy of the production FN-DMC energy differences. The proposed scheme leads to no significant increase in the local energy variance, indicating that the total CPU cost of large-scale benchmark noncovalent interaction energy FN-DMC calculations may be reduced.Comment: ACS book chapter, accepte

    Association between thrombocytes count and Plasmodium falcipurum infection among children under five years attending Kombewa Sub-County Hospital

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    Malaria is a leading cause of morbidity and mortality especially among children, expectant women and continues to be a global health burden. Haematological changes mark some of the most common complications in malaria as they play a major role in malaria pathology. Thrombocytes in particular, have been shown to bind infected erythrocytes and kill intracellular malaria parasites thereby indicating a protective function of platelets in the early stages. However, the mechanism that leads to low thrombocytes count in malaria infected individuals is not clear. Understanding the mechanism of platelet reduction during pathogenesis of malaria infection will be fundamental in malaria severity classification, monitoring of platelet count during infection and prompt initiation of anti-malarial therapy. In trying to understand these facts, this study sort to establish the association between platelet count and P. falciparum infection amongst children less than five years. This was a retrospective case-control study, n=549. Children below the age of five years that attending Kombewa Sub -County Hospital were recruited. Study participants were identified using the inclusion criteria and followed horizontally to retrieve platelet count from complete blood count results. The respective malaria blood film reads were then recorded, stratified to give case and control from which random sampling was done. Chi-square test and Tukey’s multiple comparison tests from Graph pad prism 5 were used in the analysis. The odds of exposure to low platelet count were then established with a confidence level of 95%. We found significant difference between the cases and controls in regard to parasite density (Chi square=157.5, p value &lt;0.05), mean parasite density in controls =2042.1/?l compared to cases= 142880/?l. The odds of cases being exposed to malaria was 12 times more than controls (OR=12.382, 95%). We also found no variation in thrombocytes counts in relation to gender, children with thrombocytopenia were having higher parasite density, parasite density as a result of P.falciparum infection is not dependent on gender and children that suffered malarial infection were twelve times likely to develop thrombocytopenia. Further studies are then recommended to establish the effects of incorporation of platelet aggregation inhibitors such as aspirin in malaria treatment.Key Words: Plasmodium falciparum, thrombocytopenia, infectio
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