Changes in murine anorectum signaling across the life course

Background: Increasing age is associated with an increase in the incidence of chronic constipation and fecal impaction. The contribution of the natural aging process to these conditions is not fully understood. This study examined the effects of increasing age on the function of the murine anorectum.Methods: The effects of increasing age on cholinergic, nitrergic, and purinergic signaling pathways in the murine anorectum were examined using classical organ bath assays to examine tissue function and electrochemical sensing to determine age‐related changes in nitric oxide and acetylcholine release.Key Results: Nitrergic relaxation increased between 3 and 6 months, peaked at 12 months and declined in the 18 and 24 months groups. These changes were in part explained by an age‐related decrease in nitric oxide (NO) release. Cholinergic signaling was maintained with age by an increase in acetylcholine (ACh) release and a compensatory decrease in cholinesterase activity. Age‐related changes in purinergic relaxation were qualitatively similar to nitrergic relaxation although the relaxations were much smaller. Increasing age did not alter the response of the anorectum smooth muscle to exogenously applied ACh, ATP, sodium nitroprusside or KCl. Similarly, there was no change in basal tension developed by the anorectum.Conclusions and Inferences: The decrease in nitrergic signaling with increasing age may contribute to the age‐related fecal impaction and constipation previously described in this model by partially obstructing defecation

MAGIC sensitivity to millisecond-duration optical pulses

The MAGIC telescopes are a system of two Imaging Atmospheric Cherenkov Telescopes (IACTs) designed to observe very high energy (VHE) gamma rays above ~50 GeV. However, as IACTs are sensitive to Cherenkov light in the UV/blue and use photo-detectors with a time response well below the ms scale, MAGIC is also able to perform simultaneous optical observations. Through an alternative system installed in the central PMT of MAGIC II camera, the so-called central pixel, MAGIC is sensitive to short (1ms - 1s) optical pulses. Periodic signals from the Crab pulsar are regularly monitored. Here we report for the first time the experimental determination of the sensitivity of the central pixel to isolated 1-10 ms long optical pulses. The result of this study is relevant for searches of fast transients such as Fast Radio Bursts (FRBs).Comment: Proceedings of the 35th International Cosmic Ray Conference (ICRC 2017), Bexco, Busan, Korea (arXiv:1708.05153

Optimal dose calibration in radiotherapy

In this paper, the tools provided by the theory of Optimal Experimental Design are applied to a nonlinear calibration model. This is motivated by the need of estimating radiation doses using radiochromic films for radiotherapy purposes. The calibration model is in this case nonlinear and the explanatory variable cannot be worked out explicitly from the model. In this case an experimental design has to be found on the dependent variable. For that, the inverse function theorem will be used to obtain an information matrix to be optimized. Optimal designs on the response variable are computed from two different perspectives, first for fitting the model and estimating each of the parameters and then for predicting the proper dose. While the first is a common point of view in a general context of the Optimal Experimental Design, the latter is actually the main objective of the calibration problem for the practitioners and algorithms for computing these optimal designs are also provided. The optimal designs obtained have just three different points in their support, but practitioners usually demand for more support points. Thus, a methodology for computing space-filling designs is also provided when the support points are forced to follow some mathematical rule, such as arithmetic or geometric sequences. Cross efficiencies of all these designs are computed in order to show their ability for different goals

Optimal experimental design for cytogenetic dose-response calibration curves

Purpose: To introduce optimal experimental design techniques in the cytogenetic biological dosimetry practice. This includes the development of a new optimatility criterion for the calibration of radiation doses. Materials and Methods: The most typical optimal design criterion and the one developed in this research are introduced and applied in an example from the litera- ture. In another example from the literature, a simulation study has been performed to compare the standard error of the dose estimation using di erent experimental designs. An RStudio project and a GitHub project have been developed to repro- duce these results. Results: It is appreciated how the application of optimal experimental design tech- niques can reduce the standard error of biodosimetric dose estimations. Conclusions: Optimal experimental design techniques jointly with practitioners re- quirements may be applied. This practice would not involve an additional laboratory work

Biomass-derived activated carbon as catalyst in the leaching of metals from a copper sulfide concentrate

Chalcopyrite is the resource with the highest amount of Cu content representing around 70–80% of the known reserves in the world. However, chalcopyrite like other copper sulfides, is usually found in deposits with grades around 0.4–0.5% copper. The exploitation of these reserves using traditional flotation methods followed by pyrometallurgical treatment of copper concentrate is at the limit of economic viability. Hydrometallurgical route would be more suitable for treating of these low-graded sulfide ores. However, chalcopyrite is refractory in ferric/sulfuric acid media and shows slow dissolution rates. For this a number of researches were carried out to accelerate the kinetics of leaching by adding pyrite, iron powder, nanosized silica, coal and activated carbon. The main objective of the present work was to study the use of one biomass-derived activated carbon as catalysts in the leaching of copper from chalcopyrite. Sulfuric acid solution of pH 1 with 5 g L-1 of Fe3+ was used as leaching agent. Experiments were performed at 90 °C and 250 rpm, during 48 and 96 h. Concentration of Cu, Zn, As, Sb and Co in the liquid phase was determined in order to evaluate their extraction degree, whereas solid residues were characterized by SEM-EDS and XRD. The presence of biomass-derived activated carbon significantly increased the extraction of copper, decreasing the leaching of arsenic. Furthermore, the use of biomass-derived activated carbon led to lower amounts of crystalline sulfur in the final residue

Influencia de la precipitación sobre las concentraciones de S02 y humos de la atmósfera de Salamanca

[ES]Hemos estudiado la relación entre las concentraciones de so2 y humos y la precipitación a partir del efecto de lavado ejercido por la lluvia sobre estos contaminantes, a lo largo de tres años (1979-81).[EN]A study has been made of the relationship between the concentrations of so2 and smoke and the precipitation through the washoult effect carried out by rain on these pollutants over a period of three years (1979-82)

Tipos de tiempo asociados con altos niveles de contaminación en Salamanca

[ES]En este trabajo hemos establecido los tipos de tiempo que aparecen con mayor frecuencia asociados a altos niveles de contaminación para un período de 4 años (1978-1982).[EN]In this paper, we have established the weather types that were more frequently associated with high air pollution levels over 4 years period (1978-1982)

Desenvolvimento do agroturismo em Cachoeiras de Macacu, RJ: subsídios ao planejamento da atividade agroturística associada à produção agropecuária de base familiar.

O Município de Cachoeiras de Macacu está situado numa região que exibe grande riqueza de atributos naturais, apresentando vocação para a exploração de atividades turísticas de cunho rural e ecológico, e ainda, por desenvolver agropecuária expressiva, apresenta potencial para explorar o segmento do turismo associado às atividades produtivas do meio rural (agricultura, pecuária e silvicultura), o agroturismo. Entretanto, para que a atividade seja sustentável, requer planejamento, sendo necessário um estudo prévio de viabilidade, que considere aspectos físicos, sociais, culturais, econômicos e ambientais. Face a isso, este estudo teve por objetivo fazer um levantamento diagnóstico sobre as potencialidades e limitações do Município de Cachoeiras de Macacu em relação ao agroturismo; e com base nisso, elaborar um plano preliminar para subsidiar o desenvolvimento da atividade. Para tanto, foram compilados dados secundários e primários. Os dados secundários consultados referem-se a resultados de pesquisas e estudos realizados nos últimos 10 anos na região pela Embrapa Solos e outras instituições de pesquisa e/ou ensino, e de projetos que complementam e integram temas de interesse comum. Os dados primários foram coletados junto aos atores locais (produtores rurais familiares e seus representantes, funcionários de instituições públicas, empreendedores rurais, proprietários de meios de hospedagem, entre outros), por meio de campanhas de campo realizadas entre 2012 e 2014, nas comunidades rurais produtivas com base na agricultura familiar. O conjunto de dados inventariados e a síntese do diagnóstico obtido serviram de base para a elaboração do plano preliminar. A presente versão intitulada: "Plano Preliminar para o Desenvolvimento do Agroturismo em Cachoeiras de Macacu, RJ" representa um primeiro passo para orientar o planejamento do agroturismo integrado à produção agropecuária de base familiar no município. Sua efetivação envolve os poderes públicos estaduais e municipais e deve ser impulsionado pela comunidade, para garantir que a atividade se desenvolva em harmonia com suas expectativas e anseios.bitstream/item/142637/1/BPD-244-Desenv-Agroturismo-Cach-Macacu.pd

Contrastación de hipótesis en diseños multivariados split-plot con matrices de dispersión arbitrarias

El presente trabajo examina diversos procedimientos para contrastar hipótesis nulas globales, correspondientes a datos obtenidos mediante diseños multivariados split-plot cuando se incumple el supuesto de homogeneidad de las matrices de dispersión. Un examen de estos procedimientos para un amplio número de variables confirma, por un lado, la robustez del procedimiento multivariado de Welch-James dado por Johansen (1980) para probar el efecto principal de los ensayos y, por otro, la robustez de la generalización multivariada del procedimiento de Brown-Forsythe (1974) para probar la interacción de los grupos x los ensayos. Nuestros resultados también ponen de relieve que las diferencias de potencia eran pequeñas en aquellas condiciones en que tanto el procedimiento de Welch-James como de Brown-Forsythe controlaban las tasas de error de Tipo I