How much effort is required to accurately describe the complex ecology of a rodent‐borne viral disease?

We use data collected on 18, 1-ha live trapping grids monitored from 1994 through 2005 and on five of those grids through 2013 in the mesic northwestern United States to illustrate the complexity of the deer mouse (Peromyscus maniculatus)/Sin Nombre virus (SNV) host-pathogen system. Important factors necessary to understand zoonotic disease ecology include those associated with distribution and population dynamics of reservoir species as well as infection dynamics. Results are based on more than 851,000 trap nights, 16,608 individual deer mice and 10,572 collected blood samples. Deer mice were distributed throughout every habitat we sampled and were present during every sampling period in all habitats except high altitude habitats over 1900 m. Abundance varied greatly among locations with peak numbers occurring mostly during fall. However, peak rodent abundance occurred during fall, winter and spring during various years on three grids trapped 12 months/yr. Prevalence of antibodies to SNV averaged 3.9% to 22.1% but no grids had mice with antibodies during every month. The maximum period without antibody-positive mice ranged from 1 to 52 months, or even more at high altitude grids where deer mice were not always present. Months without antibody-positive mice were more prevalent during fall than spring. Population fluctuations were not synchronous over broad geographic areas and antibody prevalences were not well spatially consistent, differing greatly over short distances. We observed an apparently negative, but nonstatistically significant relationship between average antibody prevalence and average deer mouse population abundance and a statistically significant positive relationship between the average number of antibody positive mice and average population abundance. We present data from which potential researchers can estimate the effort required to adequately describe the ecology of a rodentborne viral system. We address different factors affecting population dynamics and hantavirus antibody prevalence and discuss the path to understanding a complex rodent-borne disease system as well as the obstacles in that path.Fil: Douglass, Richard J.. University of Montana; Estados UnidosFil: Vadell, María Victoria. Universidad Nacional de San Martín. Instituto de Investigaciones e Ingeniería Ambiental. Laboratorio de Ecología de Enfermedades Transmitidas por Vectores; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Regional scale environmental variables complementing a Risk Model of Chagas Disease vectorial transmission

In thIS study we present advances in the analysis of environmental variables obtained from moderate resolution satellite images and their association with infestation indexes by Triatoma infestans (vector of Chagas disease). The environmental variables considered are the result of climatology and anomalY summaries derived from MODIS sensor time series (products MOD11A2 and MOD13A2) for the period 2000 to 2015), land use from Serena and precipitation from TRMM. The infestation, which was measured at the locality / rural LOCATION level, is expressed as a percentage of households with presence of T. infestans. Data was collected from the National Chagas service. Generalized linear models are proposed to associate the infestation with the environmental variables OBTAINED FROM SATELLITE IMAGES and other local conditions (characteristics of the dwellings and the presence of domestic animals). In general, the environmental variables considered in the models have more influence on Infestation indexes than the locals variables. The variables with the best adjustment were: annual average of LST of the years 2013 and 2015, the NDVI of 2014 and the anomalies of NDVI of the same year. These variables showed higher weights than the variables representing local conditions. From an eco-epidemiological perspective, the usage of products derived from sensors with Medium resolution with national coverage are tools which allow decision makers to generate more accurate responses in less time

An ion beam spot size monitor based on a nano-machined Si photodiode probed by means of the ion beam induced charge technique

In this work the utilization of the Ion Beam Induced Charge (IBIC) technique is explored to assess the resolution a 2 MeV Li + ion microbeam raster scanning a micrometer-sized FIB-machined hollows in a silicon photodiode. The analysis of the maps crossing the FIB machined structures evidenced a drop in charge collection efficiency across the perimeter of the hollows combined with a significant recovery of the signal amplitude at the center of the microstructures, thus forming a micrometer-sized feature which can be exploited to estimate the resolution of the probing beam. The results were interpreted according to numerical simulations based on the Shockley-Ramo-Gunn as originating from a FIB-induced surface space charge density. These results offered additional information with respect to what achievable by a confocal photocurrent microscopy analysis of the same device, due to the significantly shorter focal depth of the latter with respect to the probing ion beam. This study suggests the viability of an effective method to evaluate of the resolution of ion microbeams in processes and experiments, which could be beneficial in emerging fields (deterministic implantation, micro-radiobiology, ion lithography) demanding beam spot sizes below the micrometer scale

Disentangling the complexity of groundwater dependent social-ecological systems

Groundwater resources are part of larger social-ecological systems. In this chapter, we review the various dimensions of these complex systems in order to uncover the diversity of elements at stake in the evolution of an aquifer and the loci for possible actions to control its dynamics. Two case studies illustrate how the state of an aquifer is embedded in a web of biophysical and sociopolitical processes. We propose here a holistic view through an IGM-scape that describes the various possible pathways of evolution for a groundwater related social-ecological system. Then we describe the elements of this IGM-scape starting with physical entities and processes, including relations with surface water and quality issues. Interactions with society bring an additional layer of considerations, including decisions on groundwater abstraction, land use changes and even energy related choices. Finally we point out the policy levers for groundwater management and their possible consequences for an aquifer, taking into account the complexity of pathways opened by these levers

Insulin-Stimulated Degradation of Apolipoprotein B100: Roles of Class II Phosphatidylinositol-3-Kinase and Autophagy

Both in humans and animal models, an acute increase in plasma insulin levels, typically following meals, leads to transient depression of hepatic secretion of very low density lipoproteins (VLDL). One contributing mechanism for the decrease in VLDL secretion is enhanced degradation of apolipoprotein B100 (apoB100), which is required for VLDL formation. Unlike the degradation of nascent apoB100, which occurs in the endoplasmic reticulum (ER), insulin-stimulated apoB100 degradation occurs post-ER and is inhibited by pan-phosphatidylinositol (PI)3-kinase inhibitors. It is unclear, however, which of the three classes of PI3-kinases is required for insulin-stimulated apoB100 degradation, as well as the proteolytic machinery underlying this response. Class III PI3-kinase is not activated by insulin, but the other two classes are. By using a class I-specific inhibitor and siRNA to the major class II isoform in liver, we now show that it is class II PI3-kinase that is required for insulin-stimulated apoB100 degradation in primary mouse hepatocytes. Because the insulin-stimulated process resembles other examples of apoB100 post-ER proteolysis mediated by autophagy, we hypothesized that the effects of insulin in autophagy-deficient mouse primary hepatocytes would be attenuated. Indeed, apoB100 degradation in response to insulin was significantly impaired in two types of autophagy-deficient hepatocytes. Together, our data demonstrate that insulin-stimulated apoB100 degradation in the liver requires both class II PI3-kinase activity and autophagy. © 2013 Andreo et al

Bronchoscopist's perception of the quality of the single-use bronchoscope (Ambu aScope4™) in selected bronchoscopies: a multicenter study in 21 Spanish pulmonology services

Background: The disposable bronchoscope is an excellent alternative to face the problem of SARS-CoV-2 and other cross infections, but the bronchoscopist's perception of its quality has not been evaluated. Methods: To evaluate the quality of the Ambu-aScope4 disposable bronchoscope, we carried out a cross-sectional study in 21 Spanish pulmonology services. We use a standardized questionnaire completed by the bronchoscopists at the end of each bronchoscopy. The variables were described with absolute and relative frequencies, measures of central tendency and dispersion depending on their nature. The existence of learning curves was evaluated by CUSUM analysis. Results: The most frequent indications in 300 included bronchoscopies was bronchial aspiration in 69.3% and the median duration of these was 9.1 min. The route of entry was nasal in 47.2% and oral in 34.1%. The average score for ease of use, image, and aspiration quality was 80/100. All the planned techniques were performed in 94.9% and the bronchoscopist was satisfied in 96.6% of the bronchoscopies. They highlighted the portability and immediacy of the aScope4TM to start the procedure in 99.3%, the possibility of taking and storing images in 99.3%. The CUSUM analysis showed average scores > 70/100 from the first procedure and from the 9th procedure more than 80% of the scores exceeded the 80/100 score. Conclusions: The aScope4™ scored well for ease of use, imaging, and aspiration. We found a learning curve with excellent scores from the 9th procedure. Bronchoscopists highlighted its portability, immediacy of use and the possibility of taking and storing images