Space simulation facilities providing a stable thermal vacuum facility

CBI has recently constructed the Intermediate Thermal Vacuum Facility. Built as a corporate facility, the installation will first be used on the Boost Surveillance and Tracking System (BSTS) program. It will also be used to develop and test other sensor systems. The horizontal chamber has a horseshoe shaped cross section and is supported on pneumatic isolators for vibration isolation. The chamber structure was designed to meet stability and stiffness requirements. The design process included measurement of the ambient ground vibrations, analysis of various foundation test article support configurations, design and analysis of the chamber shell and modal testing of the chamber shell. A detailed 3-D finite element analysis was made in the design stage to predict the lowest three natural frequencies and mode shapes and to identify local vibrating components. The design process is described and the results are compared of the finite element analysis to the results of the field modal testing and analysis for the 3 lowest natural frequencies and mode shapes. Concepts are also presented for stiffening large steel structures along with methods to improve test article stability in large space simulation facilities

Place matters: how community development departments are rediscovering communities

Community development

Amylin reduces plaque forming amyloid fragments and upregulates APP cleavage mechanisms.

Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by deposition of amyloid plaques in the brain. Amyloid-β (AB) fragments (1-42) are the main components of plaques and are formed by the sequential cleavage of amyloid precursor protein (APP) by β-secretase and ϒ-secretase. Another enzyme, α-secretase, cleaves within the amyloid-β sequence preventing it from aggregating. Previous studies have shown that peripheral administration of a non-aggregating form of the metabolic hormone amylin, an amyloid with similar aggregating properties, improves cognitive function in mouse models of AD and reduces amyloid-β plaque levels. However, how this hormone regulates amyloid-β levels is not known. The purpose of our research was to study the effects of amylin administration on the levels of pro-aggregation soluble amyloid-β fragments (1-42) the expression of α- and β-secretases and the C-terminal fragments that result from enzyme cleavage in the APP/PS1 mouse model of AD. Our data indicate that amylin treatment reduced formic acid-soluble Amyloid-β 1-42 fragments (aggregates). These reductions were paralleled by general upregulation of cleavage enzymes. Taken together, our data demonstrate that amylin may be a potential new therapeutic target for Alzheimer’s disease through its ability to regulate amyloid-beta processing and aggregation. Keywords: Amylin, Alzheimer’s disease, amyloid-β, APP, α-secretase, β-secretase.</p

Understanding HIV Care Provider Attitudes Regarding Intentions to Prescribe PrEP

INTRODUCTION: Pre-exposure prophylaxis (PrEP) is a promising approach to reducing HIV incidence. Thus garnering the support of HIV providers, who are most familiar with antiretrovirals and likely to encounter patients in HIV serodiscordant relationships, to scale-up PrEP implementation is essential. We sought to determine whether certain subgroups of HIV providers were more likely to intend to prescribe PrEP. METHODS: Surveys were administered to HIV providers in Miami, Florida and Washington, DC. Composite scores were developed to measure PrEP knowledge, experience, and likelihood of prescribing. Latent class analysis (LCA) was used to stratify provider attitudes toward PrEP. RESULTS: Among 142 HIV providers, 73.2% had cared for more than 20 HIV-infected patients in the prior 3 months; 17% had ever prescribed PrEP. LCA identified two classes of providers (entropy 0.904); Class 1 (n=95) found PrEP less effective and perceived barriers to prescribing it; Class 2 (n=47) perceived PrEP as moderately effective and perceived fewer barriers to prescribing it. Compared to Class 2, Class 1 had significantly less experience with PrEP delivery (t(22.7)=2.88, p=0.009) and was significantly less likely to intend to prescribe to patients with multiple sex partners (20% vs. 43%, p=0.04) and those with a drug use history (7% vs. 24%, p=0.001). CONCLUSIONS: While most HIV providers found PrEP to be effective, those considering it less effective had limited knowledge and experience with PrEP and had lesser intentions to prescribe. Provider training regarding whom should receive PrEP and addressing potential barriers to PrEP provision are needed if this HIV prevention method is to be optimized