Modulation of endoglin expression in islets of langerhans by VEGF reveals a novel regulator of islet endothelial cell function

BACKGROUND: Endoglin/CD105 is an auxiliary receptor for transforming growth factor-β with established roles in vascular remodelling. It has recently been shown that heterozygous endoglin deficiency in mice decreases insulin secretion in an animal model of obesity, highlighting a potential role for endoglin in the regulation of islet function. We have previously identified two different populations of endoglin expressing cells in human and mouse islets which are: (i) endothelial cells (ECs) and (ii) islet mesenchymal stromal cells. The contribution of islet EC endoglin expression to islet development and sensitivity to VEGF is unknown and is the focus of this study. RESULTS: In vitro culture of mouse islets with VEGF164 for 48 h increased endoglin mRNA levels above untreated controls but VEGF did not modulate VEGFR2, CD31 or CD34 mRNA expression or islet viability. Removal of EC-endoglin expression in vivo reduced islet EC area but had no apparent effect on islet size or architecture. CONCLUSION: EC-specific endoglin expression in islets is sensitive to VEGF and plays partial roles in driving islet vascular development, however such regulation appears to be distinct to mechanisms required to modulate islet viability and size

Financing rural homes in Missouri

Missouri Agricultural Experiment Station and the Farm Production Economics Division, Economic Research Service, U.S. Department of Agriculture, cooperating.Digitized 2007 AES.Includes bibliographical references (page 43)

XUV Frequency Combs via Femtosecond Enhancement Cavities

We review the current state of tabletop extreme ultraviolet (XUV) sources based on high harmonic generation (HHG) in femtosecond enhancement cavities (fsEC). Recent developments have enabled generation of high photon flux (1014 photons/sec) in the XUV, at high repetition rates (>50 MHz) and spanning the spectral region from 40 nm - 120 nm. This level of performance has enabled precision spectroscopy with XUV frequency combs and promises further applications in XUV spectroscopic and photoemission studies. We discuss the theory of operation and experimental details of the fsEC and XUV generation based on HHG, including current technical challenges to increasing the photon flux and maximum photon energy produced by this type of system. Current and future applications for these sources are also discussed.Comment: invited review article, 38 page

Childhood Trauma and Adulthood Physical Health in Mexico.

Background The present study examined the effect of childhood trauma on adulthood physical health among a randomly selected sample of adults (N = 2,177) in urban Mexico. Methods Adults were interviewed about their experiences of trauma, post-traumatic stress disorder, depression, and physical health symptoms using Module K of the Composite International Diagnostic Interview, the Center for Epidemiologic Studies Depression Scale, and the Physical Symptoms Checklist. Results Trauma was prevalent, with 35% reporting a traumatic event in childhood. In general, men reported more childhood trauma than women, with the exception of childhood sexual violence where women reported more exposure. For men, childhood sexual violence was related to total and all physical health symptom subscales. For women, childhood sexual violence was related to total, muscular-skeletal, and gastrointestinal-urinary symptoms; hazards/accidents in childhood were related to total, muscular-skeletal, cardio-pulmonary, and nose-throat symptom subscales. Depression mediated the relationship between childhood sexual violence and physical health symptoms for men and women. Among women only, PTSD mediated the relationship between childhood sexual violence and total, muscular-skeletal, and gastrointestinal-urinary symptoms. PTSD also mediated the relationship between hazards/accidents in childhood and total, muscular-skeletal, cardio-pulmonary, and nose-throat symptoms. Conclusion These findings can be used to increase awareness among general practitioners, as well as community stakeholders, about the prevalence of childhood trauma in Mexican communities and its impact on subsequent physical health outcomes. With this awareness, screening practices could be developed to identify those with trauma histories in order to increase positive health outcomes among trauma survivors

Data Quality in Multi-sited Cross-Sectional and Panel Studies.

The authors address the issues faced while collecting survey data as part of a large multisite, multidisciplinary long-term project using interviewers rather than self-administered questionnaires in a country in which the researchers are not native. The issues pertain to the collection of high-quality data that accurately measure the variables of interest from which generalizations can be made. Three issues were prominent: potential cross-cultural variation in the validity of measures; how to manage multiple control sites and multiple study sites; and how to control for problems presented by series/panel data (i.e., the influence of prior interviews or subsequent intervening events on later interviews). The authors addressed these issues through five strategies at different points in the study. This discussion concerns the challenges and benefits of using these techniques to address the three main issues

The role of individual well-being in risk perception and evacuation for chronic vs. acute natural hazards in Mexico.

This paper examines how situational and cognitive measures of well-being associated with chronic and acute hazardous conditions affect perception of risk. The research was conducted in two disaster sites in the state of Puebla, Mexico; risk perception from chronic exposure to volcanic eruptions of Popocatépetl was investigated in San Pedro Benito Juárez, and risk perception from acute exposure to a flood/mudslide event was explored in Teziutlán. The research employed structured questionnaire surveys in both communities to collect information that included demographic information (e.g., age, sex, affinity to place, etc.), evacuation history, hazard belief systems, social networks, and physical and mental health related to hazard exposure. While well-being scores were worse for Teziutlán residents than for people in San Pedro Benito Juárez, with few exceptions it was in the chronic hazard site of San Pedro Benito Juárez and not in Teziutlán that individual well-being predicted risk perception. The results of this research can be used to tailor risk communication and educational policies differently for acute disaster vs. chronic hazard settings, as well as identify subpopulations for specific kinds of support or education

Cross-Cultural and Site-Based Influences on Demographic, Well-being, and Social Network Predictors of Risk Perception in Hazard and Disaster Settings in Ecuador and Mexico

Although virtually all comparative research about risk perception focuses on which hazards are of concern to people in different culture groups, much can be gained by focusing on predictors of levels of risk perception in various countries and places. In this case, we examine standard and novel predictors of risk perception in seven sites among communities affected by a flood in Mexico (one site) and volcanic eruptions in Mexico (one site) and Ecuador (five sites). We conducted more than 450 interviews with questions about how people feel at the time (after the disaster) regarding what happened in the past, their current concerns, and their expectations for the future. We explore how aspects of the context in which people live have an effect on how strongly people perceive natural hazards in relationship with demographic, well-being, and social network factors. Generally, our research indicates that levels of risk perception for past, present, and future aspects of a specific hazard are similar across these two countries and seven sites. However, these contexts produced different predictors of risk perception—in other words, there was little overlap between sites in the variables that predicted the past, present, or future aspects of risk perception in each site. Generally, current stress was related to perception of past danger of an event in the Mexican sites, but not in Ecuador; network variables were mainly important for perception of past danger (rather than future or present danger), although specific network correlates varied from site to site across the countries

Postdisaster reciprocity and the development of inequality in personal networks

Within the context of major changes in economics, population distribution, and lifestyles around the world, people continue to rely on personal relationships for support. People also often create or find themselves in relationships that are alternatively asymmetrical or balanced. In this study, we are interested in how people face acute or chronic hazards and how asymmetrical or balanced exchange relationships are associated with different types of social support in these contexts. This study examines the degree to which populations in three disaster settings–flooding in Mexico and volcanic eruptions in Mexico and Ecuador–show variation in the degree and form of reciprocity. We found people on average to engage in giving and/or receiving with three to five people in their personal networks. Most of these relationships were reciprocal, but those that were not reciprocal suggested potential inequality in these rural communities

Exploring tissue engineering

In this Creative Inquiry, we have two main projects. Our first project aims to improve the cell culture process by eliminating the need for trypsin, an enzyme that dissociates cells from the surfaces they grow on, but also compromises cell membrane integrity and can kill cells over time. This will be done by growing cells on solar panels. Induced current via light exposure will repel the proteins from the surface so that the cells can be collected. The second project aims to determine the most viable and reproducible method of culturing cells in 3D geometry. Initial studies were done on fibroblast cells and further studies will focus on mimicking tumors. Various culturing environments, cell lines, and culturing surfaces (such as non-adhering surfaces) will be done to alter the geometries, size, and composition of the 3D geometries. The first project would be useful for pharmaceutical companies who culture large volumes of cells and for researchers who wish to study specific cell membrane proteins while the second project has applications in cancer research

Robust Ecosystem Demography (RED version 1.0): a parsimonious approach to modelling vegetation dynamics in Earth system models

A significant proportion of the uncertainty in climate projections arises from uncertainty in the representation of land carbon uptake. Dynamic global vegetation models (DGVMs) vary in their representations of regrowth and competition for resources, which results in differing responses to changes in atmospheric CO2 and climate. More advanced cohort-based patch models are now becoming established in the latest DGVMs. These models typically attempt to simulate the size distribution of trees as a function of both tree size (mass or trunk diameter) and age (time since disturbance). This approach can capture the overall impact of stochastic disturbance events on the forest structure and biomass – but at the cost of increasing the number of parameters and ambiguity when updating the probability density function (pdf) in two dimensions. Here we present the Robust Ecosystem Demography (RED), in which the pdf is collapsed onto the single dimension of tree mass. RED is designed to retain the ability of more complex cohort DGVMs to represent forest demography, while also being parameter sparse and analytically solvable for the steady state. The population of each plant functional type (PFT) is partitioned into mass classes with a fixed baseline mortality along with an assumed power-law scaling of growth rate with mass. The analytical equilibrium solutions of RED allow the model to be calibrated against observed forest cover using a single parameter – the ratio of mortality to growth for a tree of a reference mass (μ0). We show that RED can thus be calibrated to the ESA LC_CCI (European Space Agency Land Cover Climate Change Initiative) coverage dataset for nine PFTs. Using net primary productivity and litter outputs from the UK Earth System Model (UKESM), we are able to diagnose the spatially varying disturbance rates consistent with this observed vegetation map. The analytical form for RED circumnavigates the need to spin up the numerical model, making it attractive for application in Earth system models (ESMs). This is especially so given that the model is also highly parameter sparse