201 research outputs found

    Distribution and genetic variability of Staphylinidae across a gradient of anthropogenically influenced insular landscapes

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    This paper describes the distribution and genetic variability of rove beetles (Coleoptera Staphylinidae) in anthropogenically influenced insular landscapes. The study was conducted in the Azores archipelago, characterized by high anthropogenic influence and landscape fragmentation. Collections were made in five islands, from eight habitats, along a gradient of anthropogenic influence. The species of Staphylinidae from the Azores collected for this study were widely distributed and showed low habitat fidelity. Rove beetle richness was associated with anthropogenic influence and habitat type, increasing from less to more anthropogenic impacted habitats. However, genetic diversity of profiled species (i.e. with three or more specimens per species/habitat) does not seem affected by anthropogenic influence in the different habitat types, isolation or landscape fragmentation. COI haplotypes were, as a rule, not exclusive to a given island or habitat. High level of genetic divergence and nucleotide saturation was found in closely related morphological designated species, demonstrating possible disparities between currently defined taxonomic units based on morphology and molecular phylogenies of Staphylinidae. This study found evidence of cryptic speciation in the Atheta fungi (Gravenhorst) species complex which had thus far remained undetected. Similar trends were found for Oligota parva Kraatz, Oxytelus sculptus Gravenhorst, Oligota pumilio Kiesenwetter. Previous studies with lower taxonomical resolution may have underestimated the biotic diversity reported in the Azores in comparison to other Macaronesian archipelagos.info:eu-repo/semantics/publishedVersio

    Tratamiento de las roturas crónicas del tendón de Aquiles mediante la plastia de Christensen

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    Entre el 20 y 30% de las roturas del tendón de Aquiles permanece sin diagnóstico ni tratamiento. El objetivo del trabajo es evaluar la técnica quirúrgica de Christensen conservando el tejido fibroso como opción terapéutica en el tratamiento de estas lesiones. Se realizó un estudio retrospectivo descriptivo con seguimiento medio de 50 días. A los 4 meses de la intervención todos los pacientes habían recuperado la capacidad de caminar de puntas. No se reportaron complicaciones ni re-rupturas con un seguimiento de 30 semanas. La técnica descrita presenta buenos resultados funcionales y una reincorporación temprana a las actividades habituales.Entre el 20 i 30% de les ruptures del tendó d'Aquil·les roman sense diagnòstic ni tractament. L'objectiu del treball és avaluar la tècnica quirúrgica de Christensen conservant el teixit fibrós com opció terapèutica en el tractament d'aquestes lesions. Es va realitzar un estudi retrospectiu descriptiu amb seguiment mitjà de 50 dies. Als 4 mesos de la intervenció tots els pacients havien recuperat la capacitat de caminar de puntes. No es van reportar complicacions ni re-ruptures amb un seguiment de 30 setmanes. La tècnica descrita mostra bons resultats funcionals i una reincorporació precoç a les activitats habituals

    Comparative analysis of the dorsal chaetotaxy of Troglopedetes, Trogolaphysa, and Campylothorax supports the synonymization of tribes paronellini and troglopedetini (Collembola: Paronellidae)

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    Genera in subfamily Paronellinae have been grouped into five tribes, in part based on chaetotaxy. Tribes Bromacanthini, Paronellini, and Troglopedetini are characterized by having rounded scales and reduced or no macrochaetae, and although Bromacanthini harbors two well-differentiated genera, the core genera in tribes Paronellini and Troglopedetini form a homogeneous group where even generic diagnoses were, until recently, unclear. The genera assigned to Troglopedetini (Troglopedetes Absolon, Trogolaphysa Mills, and Cyphoderopsis Carpenter) harbor many species with reduced eyes number, whereas the tribe Paronellini (genera Paronella Schött, Dicranocentruga Wray and Campylothorax Schött) includes species with 6-8 eyes. Recent analyses of the chaetotaxy of Trogolaphysa and Cyphoderopsis suggest that these genera represent specialized forms related to species in Paronellini. The taxonomy of Troglopedetes, the type genus of Troglopedetini, is based almost exclusively on claw and mucro shape and dorsal macrochaetae pattern, and few details of the complete dorsal chaetotaxy of the species are known. This contribution presents a comparative analysis of the complete dorsal chaetotaxy of two species of Troglopedetes from Spain (one new to science), two new species of Trogolaphysa from the Dominican Republic and Martinique, and Campylothorax sabanus with the purpose of identifying aspects of the chaetotaxy that could provide diagnostic characters for the separation of Trogolaphysa and Troglopedetes, and a new diagnosis for tribe Troglopedetini. The analysis shows that neither the number of chaetae nor its organization or pattern of macrochaeta provides diagnostic differences between Trogolaphysa and Troglopedetes. It is also concluded that the separation of Paronellini and Troglopedetini is not justified. Troglopedetini is here synonymized with Paronellini, and a new diagnosis of Paronellini is provided

    A bioinventory of select terrestrial insects at Braidwood Dunes and Savanna Nature Preserve (Will County, Illinois)

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    We conducted an inventory of select terrestrial insect groups at Braidwood Dunes and Savanna Nature Preserve in 2011 and 2012. A total of 823 unique species, representing 19 orders of Hexapods, were recorded using a variety of sampling methods (including: light trapping, pitfall trapping, sweep net, vacuum sample, litter sample, soil core, wine rope, visual transect). Intensive studies focused on springtails (Collembola), grasshoppers, crickets and katydids (Orthoptera), true bugs (Hemiptera: Heteroptera), leafhoppers and kin (Hemiptera: Auchenorrhyncha), ground beetles (Coleoptera: Carabidae) and butterflies and macromoths (Lepidoptera). We estimate that our records comprise around 11% of the total fauna of Hexapoda that occur at this 315--‐acre site. We evaluated sampling completeness for each group and compared, richness, diversity and evenness across habitat types. Special attention was focused on midwestern remnant dependent species, conservative prairie and savanna insects of the Chicago Wilderness region, and species that appear on Illinois' list of species in greatest need of conservation. We provide the Forest Preserve District of Will County with management recommendations relating to the terrestrial for this site, as well as a large collection of images covering many of the species we encountered. Braidwood Dunes and Savanna Nature Preserve contains a variety of rare and understudied species, some of which have only infrequently been encountered. These animals play a Cover photo: Papaipema speciosissima (Noctuidae), the Osmunda Borer Moth 3 wide variety of roles within the ecosystem and various habitats, and warrant special consideration and appreciation not only by land managers but also by the members of the public with an interest in the natural world.unpublishednot peer reviewe

    Searching for solar KDAR with DUNE

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    The observation of 236 MeV muon neutrinos from kaon-decay-at-rest (KDAR) originating in the core of the Sun would provide a unique signature of dark matter annihilation. Since excellent angle and energy reconstruction are necessary to detect this monoenergetic, directional neutrino flux, DUNE with its vast volume and reconstruction capabilities, is a promising candidate for a KDAR neutrino search. In this work, we evaluate the proposed KDAR neutrino search strategies by realistically modeling both neutrino-nucleus interactions and the response of DUNE. We find that, although reconstruction of the neutrino energy and direction is difficult with current techniques in the relevant energy range, the superb energy resolution, angular resolution, and particle identification offered by DUNE can still permit great signal/background discrimination. Moreover, there are non-standard scenarios in which searches at DUNE for KDAR in the Sun can probe dark matter interactions

    Cigarettes and alcohol in relation to colorectal cancer: the Singapore Chinese Health Study

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    The relations were examined between colorectal cancer and cigarette smoking and alcohol consumption within the Singapore Chinese Health Study, a population-based, prospective cohort of 63 257 middle-aged and older Chinese men and women enrolled between 1993 and 1998, from whom baseline data on cigarette smoking and alcohol consumption were collected through in-person interviews. By 31 December 2004, 845 cohort participants had developed colorectal cancer (516 colon cancer, 329 rectal cancer). Compared with nondrinkers, subjects who drank seven or more alcoholic drinks per week had a statistically significant, 72% increase in risk of colorectal cancer hazard ratio (HR)=1.72; 95% confidence interval (CI)=1.33–2.22). Cigarette smoking was associated with an increased risk of rectal cancer only. Compared with nonsmokers, HRs (95% CIs) for rectal cancer were 1.43 (1.10–1.87) for light smokers and 2.64 (1.77–3.96) for heavy smokers. Our data indicate that cigarette smoking and alcohol use interact in the Chinese population in an additive manner in affecting risk of rectal cancer, thus suggesting that these two exposures may share a common etiologic pathway in rectal carcinogenesis

    Fully automated sequence alignment methods are comparable to, and much faster than, traditional methods in large data sets: an example with hepatitis B virus

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    Aligning sequences for phylogenetic analysis (multiple sequence alignment; MSA) is an important, but increasingly computationally expensive step with the recent surge in DNA sequence data. Much of this sequence data is publicly available, but can be extremely fragmentary (i.e., a combination of full genomes and genomic fragments), which can compound the computational issues related to MSA. Traditionally, alignments are produced with automated algorithms and then checked and/or corrected “by eye” prior to phylogenetic inference. However, this manual curation is inefficient at the data scales required of modern phylogenetics and results in alignments that are not reproducible. Recently, methods have been developed for fully automating alignments of large data sets, but it is unclear if these methods produce alignments that result in compatible phylogenies when compared to more traditional alignment approaches that combined automated and manual methods. Here we use approximately 33,000 publicly available sequences from the hepatitis B virus (HBV), a globally distributed and rapidly evolving virus, to compare different alignment approaches. Using one data set comprised exclusively of whole genomes and a second that also included sequence fragments, we compared three MSA methods: (1) a purely automated approach using traditional software, (2) an automated approach including by eye manual editing, and (3) more recent fully automated approaches. To understand how these methods affect phylogenetic results, we compared resulting tree topologies based on these different alignment methods using multiple metrics. We further determined if the monophyly of existing HBV genotypes was supported in phylogenies estimated from each alignment type and under different statistical support thresholds. Traditional and fully automated alignments produced similar HBV phylogenies. Although there was variability between branch support thresholds, allowing lower support thresholds tended to result in more differences among trees. Therefore, differences between the trees could be best explained by phylogenetic uncertainty unrelated to the MSA method used. Nevertheless, automated alignment approaches did not require human intervention and were therefore considerably less time-intensive than traditional approaches. Because of this, we conclude that fully automated algorithms for MSA are fully compatible with older methods even in extremely difficult to align data sets. Additionally, we found that most HBV diagnostic genotypes did not correspond to evolutionarily-sound groups, regardless of alignment type and support threshold. This suggests there may be errors in genotype classification in the database or that HBV genotypes may need a revision

    Push-me-pull-you: how microtubules organize the cell interior

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    Dynamic organization of the cell interior, which is crucial for cell function, largely depends on the microtubule cytoskeleton. Microtubules move and position organelles by pushing, pulling, or sliding. Pushing forces can be generated by microtubule polymerization, whereas pulling typically involves microtubule depolymerization or molecular motors, or both. Sliding between a microtubule and another microtubule, an organelle, or the cell cortex is also powered by molecular motors. Although numerous examples of microtubule-based pushing and pulling in living cells have been observed, it is not clear why different cell types and processes employ different mechanisms. This review introduces a classification of microtubule-based positioning strategies and discusses the efficacy of pushing and pulling. The positioning mechanisms based on microtubule pushing are efficient for movements over small distances, and for centering of organelles in symmetric geometries. Mechanisms based on pulling, on the other hand, are typically more elaborate, but are necessary when the distances to be covered by the organelles are large, and when the geometry is asymmetric and complex. Thus, taking into account cell geometry and the length scale of the movements helps to identify general principles of the intracellular layout based on microtubule forces

    Mutation of Ser172 in Yeast β Tubulin Induces Defects in Microtubule Dynamics and Cell Division

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    Ser172 of β tubulin is an important residue that is mutated in a human brain disease and phosphorylated by the cyclin-dependent kinase Cdk1 in mammalian cells. To examine the role of this residue, we used the yeast S. cerevisiae as a model and produced two different mutations (S172A and S172E) of the conserved Ser172 in the yeast β tubulin Tub2p. The two mutants showed impaired cell growth on benomyl-containing medium and at cold temperatures, altered microtubule (MT) dynamics, and altered nucleus positioning and segregation. When cytoplasmic MT effectors Dyn1p or Kar9p were deleted in S172A and S172E mutants, cells were viable but presented increased ploidy. Furthermore, the two β tubulin mutations exhibited synthetic lethal interactions with Bik1p, Bim1p or Kar3p, which are effectors of cytoplasmic and spindle MTs. In the absence of Mad2p-dependent spindle checkpoint, both mutations are deleterious. These findings show the importance of Ser172 for the correct function of both cytoplasmic and spindle MTs and for normal cell division
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