5,077 research outputs found

    ASICs and mammalian mechanoreceptor function

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    It is well established that some members of the Deg/ENaC super family of amiloride sensitive ion channels can participate directly in the transduction of mechanical stimuli by sensory neurons in invertebrates. A large body of work has also implicated the acid sensing ion channels family (ASIC1-4) as participants in regulating mechanoreceptor sensitivity in vertebrates. In this review we provide an overview of the physiological and genetic evidence for involvement of ASICs in mechanosensory function. On balance, the available evidence favors the idea that these channels have an important regulatory role in mechanosensory function. It is striking how diverse the consequences of Asic gene deletion are on mechanosensory function with both gain and loss of function effects being observed depending on sensory neuron type. We conclude that other, as yet unknown, molecular partners of ASIC proteins may be decisive in determining their precise physiological role in mechanosensory neurons. This article is part of the Special Issue entitled 'Acid-Sensing Ion Channels in the Nervous System'.Work in the Lewin lab was supported by a senior ERC award (Grant no 294678) and grants from the Deutsche Forschungsgemeinshaft (SFB665 and SFB958). Y-A. B. S. was funded by a fellowship from the Deutsche akademsische Austausch Dienst (DAAD). E. St. J. S. is funded by an Early Career Research Grant from the International Association for the Study of Pain. L-N. S is funded by the BBSRC Doctoral Training Program and the David James studentship

    Development and validation of an environmental DNA protocol to detect an invasive Caribbean freshwater fish, the guppy (Poecilia reticulata)

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    I.S. and C.D.S. contributed to study conception and design. I.S. secured funding for assay development, testing, and field survey work. I.S., K.-A.B., and S.B. conducted field surveys in Jamaica; I.S. and J.L.W. oversaw collection of positive and negative control samples in Oklahoma. Assay design was undertaken by E.D.H. DNA extractions, in vitro assay tests, and assessment of assay performance was overseen by S.N.S. Data analysis and summary of qPCR screening results was performed by S.N.S. and C.D.S., with contributions from J.L.W. The first draft of the manuscript was written by S.N.S., with contributions and reviews by C.D.S., I.S., J.L.W., E.D.H., K.-A.B., and S.B. All authors read and approved the final manuscript.We describe the development and validation of a qPCR assay to detect Poecilia reticulata, a highly invasive species of freshwater fish invasive to the Caribbean islands, through environmental DNA (eDNA) sampling. Originating from Trinidad, this species is invasive and detrimental to countless native tropical fish communities. A qPCR assay, consisting of a set of primers and a fluorescent probe, amplifying a 214 base pair target region of the mitochondrial Cytochrome B gene was designed for P. reticulata from existing DNA sequence data. The assay was assessed for target specificity, with no evidence of amplification in closely related or sympatrically distributed non-target species. In vitro tests indicate that the assay consistently detects P. reticulata down to concentrations of 2.0 × 10−5 ng/ÎŒl. The developed assay provides a new, practical tool for monitoring freshwater habitats throughout the Caribbean, allowing for early and rapid detection of invasive fish species of conservation concern.This research was supported by the University of Oklahoma, the Sam Noble Oklahoma Museum of Natural History, and the University of the West Indies, Mona Campus. Research was conducted in accordance with field permits in Jamaica (NEPA#18/27) and the University of Oklahoma Institutional Animal Care and Use Committee (IACUC) protocols R17-031 and R19-006. The authors thank M. Gordon, H. Bennett, E. Bennett and S.-M. Bennett-Monroe for field and laboratory assistance. Funding support for this work was provided by the University of Oklahoma and the Sam Noble Oklahoma Museum of Natural History to C.D.S and I.S.Ye

    Foodways in transition: food plants, diet and local perceptions of change in a Costa Rican NgÀbe community

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    Background Indigenous populations are undergoing rapid ethnobiological, nutritional and socioeconomic transitions while being increasingly integrated into modernizing societies. To better understand the dynamics of these transitions, this article aims to characterize the cultural domain of food plants and analyze its relation with current day diets, and the local perceptions of changes given amongst the NgĂ€be people of Southern Conte-Burica, Costa Rica, as production of food plants by its residents is hypothesized to be drastically in recession with an decreased local production in the area and new conservation and development paradigms being implemented. Methods Extensive freelisting, interviews and workshops were used to collect the data from 72 participants on their knowledge of food plants, their current dietary practices and their perceptions of change in local foodways, while cultural domain analysis, descriptive statistical analyses and development of fundamental explanatory themes were employed to analyze the data. Results Results show a food plants domain composed of 140 species, of which 85 % grow in the area, with a medium level of cultural consensus, and some age-based variation. Although many plants still grow in the area, in many key species a decrease on local production–even abandonment–was found, with much reduced cultivation areas. Yet, the domain appears to be largely theoretical, with little evidence of use; and the diet today is predominantly dependent on foods bought from the store (more than 50 % of basic ingredients), many of which were not salient or not even recognized as ‘food plants’ in freelists exercises. While changes in the importance of food plants were largely deemed a result of changes in cultural preferences for store bought processed food stuffs and changing values associated with farming and being food self-sufficient, NgĂ€be were also aware of how changing household livelihood activities, and the subsequent loss of knowledge and use of food plants, were in fact being driven by changes in social and political policies, despite increases in forest cover and biodiversity. Conclusions NgĂ€be foodways are changing in different and somewhat disconnected ways: knowledge of food plants is varied, reflecting most relevant changes in dietary practices such as lower cultivation areas and greater dependence on food from stores by all families. We attribute dietary shifts to socioeconomic and political changes in recent decades, in particular to a reduction of local production of food, new economic structures and agents related to the State and globalization

    Decaying into the Hidden Sector

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    The existence of light hidden sectors is an exciting possibility that may be tested in the near future. If DM is allowed to decay into such a hidden sector through GUT suppressed operators, it can accommodate the recent cosmic ray observations without over-producing antiprotons or interfering with the attractive features of the thermal WIMP. Models of this kind are simple to construct, generic and evade all astrophysical bounds. We provide tools for constructing such models and present several distinct examples. The light hidden spectrum and DM couplings can be probed in the near future, by measuring astrophysical photon and neutrino fluxes. These indirect signatures are complimentary to the direct production signals, such as lepton jets, predicted by these models.Comment: 40 pages, 5 figure

    Implication of human papillomavirus-66 in vulvar carcinoma: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>Vulvar cancer in older women is seldom associated with human papillomavirus infection.</p> <p>Case presentation</p> <p>We present the case of an 80-year-old Greek Caucasian woman with an undetermined obstetric and gynecologic history. The patient underwent radical vulvectomy and bilateral inguinal lymphadenectomy for a vulvar carcinoma. A human papillomavirus infection was suggested on the basis of histological and cytological examinations followed by human papillomavirus DNA typing, which revealed the presence of human papillomavirus-66.</p> <p>Conclusion</p> <p>Even though human papillomavirus-16 and human papillomavirus-18 are most frequently implicated in the pathogenesis of vulvar carcinoma, human papillomavirus-66 can also be regarded as a causative factor. Suspicious lesions should be biopsied, and in the presence of carcinoma, vulvectomy with bilateral lymphadenectomy, if necessary, must be performed. Furthermore, polymerase chain reaction assay analysis with clinical arrays in cytological samples is an accurate test for the detection of a wide range of human papillomavirus genotypes and can be used to verify the infection and specify the human papillomavirus type implicated.</p

    An Age-Structured Extension to the Vectorial Capacity Model

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    Vectorial capacity and the basic reproductive number (R(0)) have been instrumental in structuring thinking about vector-borne pathogen transmission and how best to prevent the diseases they cause. One of the more important simplifying assumptions of these models is age-independent vector mortality. A growing body of evidence indicates that insect vectors exhibit age-dependent mortality, which can have strong and varied affects on pathogen transmission dynamics and strategies for disease prevention.Based on survival analysis we derived new equations for vectorial capacity and R(0) that are valid for any pattern of age-dependent (or age-independent) vector mortality and explore the behavior of the models across various mortality patterns. The framework we present (1) lays the groundwork for an extension and refinement of the vectorial capacity paradigm by introducing an age-structured extension to the model, (2) encourages further research on the actuarial dynamics of vectors in particular and the relationship of vector mortality to pathogen transmission in general, and (3) provides a detailed quantitative basis for understanding the relative impact of reductions in vector longevity compared to other vector-borne disease prevention strategies.Accounting for age-dependent vector mortality in estimates of vectorial capacity and R(0) was most important when (1) vector densities are relatively low and the pattern of mortality can determine whether pathogen transmission will persist; i.e., determines whether R(0) is above or below 1, (2) vector population growth rate is relatively low and there are complex interactions between birth and death that differ fundamentally from birth-death relationships with age-independent mortality, and (3) the vector exhibits complex patterns of age-dependent mortality and R(0) ∌ 1. A limiting factor in the construction and evaluation of new age-dependent mortality models is the paucity of data characterizing vector mortality patterns, particularly for free ranging vectors in the field

    Observation of two new Ξb−\Xi_b^- baryon resonances

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    Two structures are observed close to the kinematic threshold in the Ξb0π−\Xi_b^0 \pi^- mass spectrum in a sample of proton-proton collision data, corresponding to an integrated luminosity of 3.0 fb−1^{-1} recorded by the LHCb experiment. In the quark model, two baryonic resonances with quark content bdsbds are expected in this mass region: the spin-parity JP=12+J^P = \frac{1}{2}^+ and JP=32+J^P=\frac{3}{2}^+ states, denoted Ξbâ€Č−\Xi_b^{\prime -} and Ξb∗−\Xi_b^{*-}. Interpreting the structures as these resonances, we measure the mass differences and the width of the heavier state to be m(Ξbâ€Č−)−m(Ξb0)−m(π−)=3.653±0.018±0.006m(\Xi_b^{\prime -}) - m(\Xi_b^0) - m(\pi^{-}) = 3.653 \pm 0.018 \pm 0.006 MeV/c2/c^2, m(Ξb∗−)−m(Ξb0)−m(π−)=23.96±0.12±0.06m(\Xi_b^{*-}) - m(\Xi_b^0) - m(\pi^{-}) = 23.96 \pm 0.12 \pm 0.06 MeV/c2/c^2, Γ(Ξb∗−)=1.65±0.31±0.10\Gamma(\Xi_b^{*-}) = 1.65 \pm 0.31 \pm 0.10 MeV, where the first and second uncertainties are statistical and systematic, respectively. The width of the lighter state is consistent with zero, and we place an upper limit of Γ(Ξbâ€Č−)<0.08\Gamma(\Xi_b^{\prime -}) < 0.08 MeV at 95% confidence level. Relative production rates of these states are also reported.Comment: 17 pages, 2 figure

    Observation of associated production of a ZZ boson with a DD meson in the~forward region

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    A search for associated production of a ZZ boson with an open charm meson is presented using a data sample, corresponding to an integrated luminosity of 1.0 fb−‘1.0\,\mathrm{fb}^{-`} of proton--proton collisions at a centre-of-mass energy of 7\,TeV, collected by the LHCb experiment. %% Seven candidate events for associated production of a ZZ boson with a D0D^0 meson and four candidate events for a ZZ boson with a D+D^+ meson are observed with a combined significance of 5.1standard deviations. The production cross-sections in the forward region are measured to be σZ→Ό+ÎŒâˆ’â€‰âŁ,D0=2.50±1.12±0.22pb\sigma_{Z\rightarrow\mu^+\mu^-\!,D^0} = 2.50\pm1.12\pm0.22pb σZ→Ό+ÎŒâˆ’â€‰âŁ,D+=0.44±0.23±0.03pb,\sigma_{Z\rightarrow\mu^+\mu^-\!,D^+} = 0.44\pm0.23\pm0.03pb, where the first uncertainty is statistical and the second systematic.Comment: 18 pages, 2 figure

    Measurements of the B+B^+, B0B^0, Bs0B_s^0 meson and Λb0\Lambda_b^0 baryon lifetimes

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    Measurements of bb-hadron lifetimes are reported using pppp collision data, corresponding to an integrated luminosity of 1.0fb−1^{-1}, collected by the LHCb detector at a centre-of-mass energy of 77Tev. Using the exclusive decays B+→J/ψK+B^+\to J/\psi K^+, B0→J/ψK∗(892)0B^0\to J/\psi K^*(892)^0, B0→J/ψKS0B^0\to J/\psi K^0_{\rm S}, Λb0→J/ψΛ\Lambda_b^0\to J/\psi \Lambda and Bs0→J/ψϕB^0_s\to J/\psi \phi the average decay times in these modes are measured to be τB+→J/ψK+\tau_{B^+\to J/\psi K^+} = 1.637±1.637 \pm 0.004 ±\pm 0.003 ps, τB0→J/ψK∗(892)0\tau_{B^0\to J/\psi K^*(892)^0} = 1.524±1.524 \pm 0.006 ±\pm 0.004 ps, τB0→J/ψKS0\tau_{B^0\to J/\psi K^0_{\rm S}} = 1.499±1.499 \pm 0.013 ±\pm 0.005 ps, τΛb0→J/ψΛ\tau_{\Lambda_b^0\to J/\psi \Lambda} = 1.415±1.415 \pm 0.027 ±\pm 0.006 ps and τBs0→J/ψϕ\tau_{B^0_s\to J/\psi \phi} = 1.480±1.480 \pm 0.011 ±\pm 0.005 ps, where the first uncertainty is statistical and the second is systematic. These represent the most precise lifetime measurements in these decay modes. In addition, ratios of these lifetimes, and the ratio of the decay-width difference, ΔΓd\Delta\Gamma_d, to the average width, Γd\Gamma_d, in the B0B^0 system, ΔΓd/Γd=−0.044±0.025±0.011\Delta \Gamma_d/\Gamma_d = -0.044 \pm 0.025 \pm 0.011, are reported. All quantities are found to be consistent with Standard Model expectations.Comment: 28 pages, 4 figures. Updated reference
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