Comprehensive testing of a defense systems communications satellite

The system level testing of the defense satellite communications system (DSCS) 3 program is reviewed. Concentration is on the results of the systems tests of the DSCS 3 development test model (DTM). The DSCS 3DTM consisted of engineering components interconnected in an open bench layout. The DTM tests were performed to demonstrate satellite electrical performance characteristics and to uncover design deficiencies and interface problems. The availability of the DTM test results prior to the fabrication of the flight model hardware permited the incorporation of necessary design changes with a minimum impact on program costs and schedules

Methods of using silica-titania clad fibers

Methods of delivering laser energy for medical procedures or industrial processes using an optical fiber having a core formed of a highly transmissive silica-based glass core and an outermost cladding layer of silica-titania glass

Spatially-explicit estimation of Wright's neighborhood size in continuous populations

Effective population size (Ne) is an important parameter in conservation genetics because it quantifies a population’s capacity to resist loss of genetic diversity due to inbreeding and drift. The classical approach to estimate Ne from genetic data involves grouping sampled individuals into discretely defined subpopulations assumed to be panmictic. Importantly, this assumption does not capture the continuous nature of populations genetically isolated by distance. Alternative approaches based on Wright’s genetic neighborhood concept quantify the local number of breeding individuals (NS) in a continuous population (as opposed to the global Ne). However, they do not reflect the potential for NS to vary spatially nor do they account for the resistance of a heterogeneous landscape to gene flow (isolation by resistance). Here, we describe an application of Wright’s neighborhood concept that provides spatially-explicit estimates of local NS from genetic data in continuous populations isolated by distance or resistance. We delineated local neighborhoods surrounding each sampled individual based on sigma (), a measure of the local extent of breeding. When was known, the linkage disequilibrium method applied to local neighborhoods produced unbiased estimates of NS that were highly variable across the landscape. NS near the periphery or areas surrounded by high resistance was as much as an order of magnitude lower compared to the center, raising the potential for a spatial component to extinction vortex dynamics in continuous populations. When is not known, it may be estimated from genetic data, but two methods we evaluated identified analysis extents that produced considerable bias or error in the estimate of NS. When is known or accurately estimated, and the assumptions of Wright’s neighborhood are met, the method we describe provides spatially explicit information regarding short-term genetic processes that may inform conservation genetic analyses and management

Re-evaluating causal modeling with mantel tests in landscape genetics

The predominant analytical approach to associate landscape patterns with gene flow processes is based on the association of cost distances with genetic distances between individuals. Mantel and partial Mantel tests have been the dominant statistical tools used to correlate cost distances and genetic distances in landscape genetics. However, the inherent high correlation among alternative resistance models results in a high risk of spurious correlations using simple Mantel tests. Several refinements, including causal modeling, have been developed to reduce the risk of affirming spurious correlations and to assist model selection. However, the evaluation of these approaches has been incomplete in several respects. To demonstrate the general reliability of the causal modeling approach with Mantel tests, it must be shown to be able to correctly identify a wide range of landscape resistance models as the correct drivers relative to alternative hypotheses. The objectives of this study were to (1) evaluate the effectiveness of the originally published causal modeling framework to support the correct model and reject alternative hypotheses of isolation by distance and isolation by barriers and to (2) evaluate the effectiveness of causal modeling involving direct competition of all hypotheses to support the correct model and reject all alternative landscape resistance models. We found that partial Mantel tests have very low Type II error rates, but elevated Type I error rates. This leads to frequent identification of support for spurious correlations between alternative resistance hypotheses and genetic distance, independent of the true resistance model. The frequency in which this occurs is directly related to the degree of correlation between true and alternative resistance models. We propose an improvement based on the relative support of the causal modeling diagnostic tests

Scientific impacts and innovations of citizen science

Citizen science, the active participation of the public in scientific research projects, is a rapidly expanding field in open science and open innovation. It provides an integrated model of public knowledge production and engagement with science. As a growing worldwide phenomenon, it is invigorated by evolving new technologies that connect people easily and effectively with the scientific community. Catalysed by citizens’ wishes to be actively involved in scientific processes, as a result of recent societal trends, it also offers contributions to the rise in tertiary education. In addition, citizen science provides a valuable tool for citizens to play a more active role in sustainable development. This book identifies and explains the role of citizen science within innovation in science and society, and as a vibrant and productive science-policy interface. The scope of this volume is global, geared towards identifying solutions and lessons to be applied across science, practice and policy. The chapters consider the role of citizen science in the context of the wider agenda of open science and open innovation, and discuss progress towards responsible research and innovation, two of the most critical aspects of science today

The Surface Wave Dynamics Experiment (SWADE)

SWADE was developed to study the dynamics of the wave field development in the open ocean with the following specific objectives: (1) to understand the development of the wave directional spectrum under various conditions; (2) to determine the effect of waves on the air/sea transfers of momentum, heat, and mass; (3) to determine breaking distributions as a function of sea state, wind, and boundary stability; and (4) to provide data and analyses for ERS-1 validation. The experiment is designed for the winter of 1990 to 1991. Four buoys will be deployed for 6 months starting October 1990 and ending March 1991. During that time period, three intensive periods of 2 weeks duration each will be selected for frequent aircraft flights for wave data collection to satisfy scientific studies, as well as ERS-1 validation needs

Transmission properties of nonlinear multimode waveguide arrays

Multimode capillary waveguide arrays containing reverse-saturable absorbers exhibit an enhancement of the nonlinear response. Experimental data are modeled by the effect of partial mode filling, influenced by fill fraction and capillary diameter

A Low-Cost, Portable Fluorescence Correlation Spectrometer for Disease Diagnosis

The DVD team is developing a cost-effective technique for measuring HIV load in resource-restricted regions. Our client is Dr. Phil Thuma and the Macha Research Trust in Zambia. Our design is based on advanced fluorescence spectroscopy that utilizes a fluorescence protein probe, confocal optics, and low-cost, low-power electronics to assess viral load in a patient blood sample. Our timeline for a functional exploded prototype is Fall 2021. Specifically, we are employing a method of spectroscopy that seeks to identify individual viruses in dilute samples by characteristic “bursts” in fluorescent and elastically scattered light. We have assembled a housing for a custom-designed detector, associated electronics, and signal processing hardware. One project goal is to integrate this modular design into a single printed circuit board. Communication between signal processing hardware and a software-based user interface implemented on a Raspberry Pi and touchscreen is achieved by the use of a Serial Peripheral Interface (SPI) protocol. The entire system is battery-powered. This system will allow for fast, effective viral load determinations in remote settings.https://mosaic.messiah.edu/engr2021/1002/thumbnail.jp

China’s emerging global role: dissatisfied responsible great power

China has (re)emerged as a great power in a world not of its own making. The distribution of power in major organisations and the dominant norms of international interactions are deemed to unfairly favour the existing Western powers, and at times obstruct China’s ability to meet national development goals. Nevertheless, engaging the global economy has been a key source of economic growth (thus helping to maintain regime stability), and establishing China’s credentials as a responsible global actor is seen as a means of ensuring continued access to what China needs. As an emerging great power that is also still in many respects a developing country, China’s challenge is to change the global order in ways that do not cause global instability or generate crises that would damage China’s own ability to generate economic growth and ensure political stability

A web-based normative calculator for the uniform data set (UDS) neuropsychological test battery

Introduction: With the recent publication of new criteria for the diagnosis of preclinical Alzheimer's disease (AD), there is a need for neuropsychological tools that take premorbid functioning into account in order to detect subtle cognitive decline. Using demographic adjustments is one method for increasing the sensitivity of commonly used measures. We sought to provide a useful online z-score calculator that yields estimates of percentile ranges and adjusts individual performance based on sex, age and/or education for each of the neuropsychological tests of the National Alzheimer's Coordinating Center Uniform Data Set (NACC, UDS). In addition, we aimed to provide an easily accessible method of creating norms for other clinical researchers for their own, unique data sets. Methods: Data from 3,268 clinically cognitively-normal older UDS subjects from a cohort reported by Weintraub and colleagues (2009) were included. For all neuropsychological tests, z-scores were estimated by subtracting the raw score from the predicted mean and then dividing this difference score by the root mean squared error term (RMSE) for a given linear regression model. Results: For each neuropsychological test, an estimated z-score was calculated for any raw score based on five different models that adjust for the demographic predictors of SEX, AGE and EDUCATION, either concurrently, individually or without covariates. The interactive online calculator allows the entry of a raw score and provides five corresponding estimated z-scores based on predictions from each corresponding linear regression model. The calculator produces percentile ranks and graphical output. Conclusions: An interactive, regression-based, normative score online calculator was created to serve as an additional resource for UDS clinical researchers, especially in guiding interpretation of individual performances that appear to fall in borderline realms and may be of particular utility for operationalizing subtle cognitive impairment present according to the newly proposed criteria for Stage 3 preclinical Alzheimer's disease