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A bstract Double electron capture by proton-rich nuclei is a second-order nuclear process analogous to double beta decay. Despite their similarities, the decay signature is quite different, potentially providing a new channel to measure the hypothesized neutrinoless mode of these decays. The Standard-Model-allowed two-neutrino double electron capture (2 νEC EC ) has been predicted for a number of isotopes, but only observed in 78 Kr, 130 Ba and, recently, 124 Xe. The sensitivity to this decay establishes a benchmark for the ultimate experimental goal, namely the potential to discover also the lepton-number-violating neutrinoless version of this process, 0 νEC EC . Here we report on the current sensitivity of the NEXT-White detector to 124 Xe 2 νEC EC and on the extrapolation to NEXT-100. Using simulated data for the 2 νEC EC signal and real data from NEXT-White operated with 124 Xe-depleted gas as background, we define an optimal event selection that maximizes the NEXT-White sensitivity. We estimate that, for NEXT-100 operated with xenon gas isotopically enriched with 1 kg of 124 Xe and for a 5-year run, a sensitivity to the 2 νEC EC half-life of 6 × 10 22 y (at 90% confidence level) or better can be reached.

We present evidence of non-excimer-based secondary scintillation in gaseous xenon, obtained using both the NEXT-White time projection chamber (TPC) and a dedicated setup. Detailed comparison with first-principle calculations allows us to assign this scintillation mechanism to neutral bremsstrahlung (NBrS), a process that is postulated to exist in xenon that has been largely overlooked. For photon emission below 1000 nm, the NBrS yield increases from about10−2photon/e−cm−1bar−1at pressure-reduced electric field values of50Vcm−1bar−1to above3×10−1photon/e−cm−1bar−1at500Vcm−1bar−1. Above1.5kVcm−1bar−1, values that are typically employed for electroluminescence, it is estimated that NBrS is present with an intensity around1photon/e−cm−1bar−1, which is about 2 orders of magnitude lower than conventional, excimer-based electroluminescence. Despite being fainter than its excimeric counterpart, our calculations reveal that NBrS causes luminous backgrounds that can interfere, in either gas or liquid phase, with the ability to distinguish and/or to precisely measure low primary-scintillation signals (S1). In particular, we show this to be the case in the “buffer” region, where keeping the electric field below the electroluminescence threshold does not suffice to extinguish secondary scintillation. The electric field leakage in this region should be mitigated to avoid intolerable levels of NBrS emission. Furthermore, we show that this new source of light emission opens up a viable path toward obtaining S2 signals for discrimination purposes in future single-phase liquid TPCs for neutrino and dark matter physics, with estimated yields up to20–50photons/e−cm−1.

Exercise Improves Insulin and Leptin Sensitivity in Hypothalamus of Wistar Rats Marcelo B.S. Flores , Maria Fernanda A. Fernandes , Eduardo R. Ropelle , Marcel C. Faria , Mirian Ueno , Lício A. Velloso , Mario J.A. Saad and José B.C. Carvalheira From the Department of Internal Medicine, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Campinas, São Paulo, Brazil Address correspondence and reprint requests to José B.C. Carvalheira, MD, Department of Internal Medicine, FCM–State University of Campinas (UNICAMP), 13081-970–Campinas, SP, Brazil. E-mail: carvalheirajbc{at}uol.com.br Abstract Prolonged exercise of medium to high intensity is known to promote a substantial effect on the energy balance of rats. In male rats, moderately to severely intense programs lead to a reduction in food intake. However, the exact causes for the appetite-suppressive effects of exercise are not known. Here, we show that intracerebroventricular insulin or leptin infusion reduced food intake in exercised rats to a greater extent than that observed in control animals. Exercise was associated with a markedly increased phosphorylation/activity of several proteins involved in leptin and insulin signal transduction in the hypothalamus. The regulatory role of interleukin (IL)-6 in mediating the increase in leptin and insulin sensitivity in hypothalamus was also investigated. Treatment with insulin or leptin markedly reduced food intake in exercised rats that were pretreated with vehicle, although no increase in sensitivity to leptin- and insulin-induced anorexia after pretreatment with anti–IL-6 antibody was detected. The current study provides direct measurements of leptin and insulin signaling in the hypothalamus and documents increased sensitivity to these hormones in the hypothalamus of exercised rats in an IL-6–dependent manner. These findings provide support for the hypothesis that the appetite-suppressive actions of exercise may be mediated by the hypothalamus. IL, interleukin IRS, insulin receptor substrate JAK, janus kinase PI, phosphatidylinositol STAT, signal transducer and activator of transcription Footnotes The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact. Accepted June 5, 2006. Received December 14, 2005. DIABETES

Production rates, chlorophyll concentrations and general composition of periphytic diatom communities growing on glass slides were sutdied in relation to environmental parameters during one sesasonal cycle in the Bay of Paranagua, southern Brazil. Slides were routinely submersed at 1, 2 and 3 m depth and recovered weekly for imcroscopic examinations, analyses of chlorophyll, cell coutns and insitu photosynthetic incubations using the Winkler titration method.

Adverse effects of using high SCC milk in cheese manufacture have been well established. The main alterations include: decreased cheese yield; increased fat and protein losses in whey ([Barbano, D.M.] et al. 1991); and compromised sensory quality ([Munro, G.L.] et al. 1984). Coagulation properties of milk are markedly affected by SCC above 500,000 cells/mL (Politis and Ng-- Kwai-Hang 1988), which can be a major problem in the cheese industry.

We studied the distribution of birds along an altitudinal gradient ranging from 800 m to 1,400 m on two slopes of the Serra do Cipó, Minas Gerais, southeastern Brazil. Ornithological surveys were conducted over transects covering open (cerrado, campo rupestre) and forested (gallery and Atlantic forest) habitats from 1994 to 2000. We found 273 bird species belonging to 51 families. Twenty-two species were restricted to higher elevations and 84 species were detected on only one slope, depending on the vegetation type they inhabited. We recorded 104 species occurring on both slopes, while 61 species were considered altitudinal generalists. Six species, including Hyacinth Visorbearer Augastes scutatus and Cipó Canastero Asthenes luizae were restricted to the highest parts of Serra do Cipó, a fragile habitat important to endemic birds of the Espinhaço Range. In the past 10 years, the Serra do Cipó region has suffered human impacts on a large scale, and conservation action must be developed to protect the fauna and flora confined to the area.

Thirty rabies virus isolates from cows and vampire bats from different regions of São Paulo State, Southeastern Brazil and three rabies vaccines were studied genetically. The analysis was based on direct sequencing of PCR-amplified products of 600 nucleotides coding for the amino terminus of nucleoprotein gene. The sequences were checked to verify their genealogical and evolutionary relationships and possible implication for health programmes. Statistical data indicated that there were no significant genetic differences between samples isolated from distinct hosts, from different geographical regions and between samples collected in the last two decades. According to the HKA test, the variability observed in the sequences is probably due to genetic drift. Since changes in genetic material may produce modifications in the protein responsible for immunogenicity of virus, which may eventually cause vaccine failure in herds, we suggest that continuous efforts in monitoring genetic diversity in rabies virus field strains, in relation to vaccine strains, must be conducted.

We surveyed Antarctic krill (Euphausia superba) under sea ice using the autonomous underwater vehicle Autosub-2. Krill were concentrated within a band under ice between 1 and 13 kilometers south of the ice edge. Within this band, krill densities were fivefold greater than that of open water. The under-ice environment has long been considered an important habitat for krill, but sampling difficulties have previously prevented direct observations under ice over the scale necessary for robust krill density estimation. Autosub-2 enabled us to make continuous high-resolution measurements of krill density under ice reaching 27 kilometers beyond the ice edge.

Continuing Health Education is a strategy that integrates learning into the work process to transform health practices. Primary health care has proved to be a powerful space for consolidating continuing education, as it promotes reflection and learning based on the local singularities of the territory. Continuing health education is an important strategy for transforming the reality of Primary health care, reinventing work, and consequently changing practices. This study aimed to identify and analyze the evidence regarding the impact of continuing education for health professionals in Primary Health Care in Brazil. This scoping review protocol that will be developed based on the Joanna Briggs Institute manual and guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR). The databases included in the study will be MEDLINE/Pubmed, Scielo, Lilacs, EMBASE, and Web of Science. Google Scholar will be used as gray literature. Studies published between 2007 and 2024 will be included, and no language restrictions will be applied. The Rayyan management software will be used as a tool to support the selection of studies. Two independent researchers will carry out a paired review to ensure the relevance of the studies. The studies will be analyzed descriptively, which will be guided by the categorization of results into three large groups: a) thematic areas covered; b) methodologies used; c) work process indicators and/or health results. Relevant aspects will be pointed out and interrelated in narrative form with the existing literature on the subject. Through the preparation of this protocol, it is aimed to identify to identify studies with evidence on the impact of continuing education in Primary Health Care in Brazil. This review could support the formulation of new professional training policies for PHC, contributing to the improvement of professional practices and the organization of work based on the needs of each territory.

We describe here the isolation of stem cells from juvenile and adult rodent skin. These cells derive from the dermis, and clones of individual cells can proliferate and differentiate in culture to produce neurons, glia, smooth muscle cells and adipocytes. Similar precursors that produce neuron-specific proteins upon differentiation can be isolated from adult human scalp. Because these cells (termed SKPs for skin-derived precursors) generate both neural and mesodermal progeny, we propose that they represent a novel multipotent adult stem cell and suggest that skin may provide an accessible, autologous source of stem cells for transplantation.