1,660 research outputs found
Monitored background radiometer
The infrared (IR) testing of the Olympus thermal model has provided a capability to perform cost effective thermal balance testing of satellites and satellite components. A high-accuracy monitored background radiometer was developed for the measurement of absorbed radiation heat flux encountered during IR thermal vacuum testing of spacecraft. The design, development, and calibration of this radiometer is described
Global Update and Trends of Hidden Hunger, 1995-2011: The Hidden Hunger Index
Background Deficiencies in essential vitamins and minerals–also termed hidden hunger–are pervasive and hold negative consequences for the cognitive and physical development of children. Methods This analysis evaluates the change in hidden hunger over time in the form of one composite indicator–the Hidden Hunger Index (HHI)–using an unweighted average of prevalence estimates from the Nutrition Impact Model Study for anemia due to iron deficiency, vitamin A deficiency, and stunting (used as a proxy indicator for zinc deficiency). Net changes from 1995–2011 and population weighted regional means for various time periods are measured. Findings Globally, hidden hunger improved (-6.7 net change in HHI) from 1995–2011. Africa was the only region to see a deterioration in hidden hunger (+1.9) over the studied time period; East Asia and the Pacific performed exceptionally well (-13.0), while other regions improved only slightly. Improvements in HHI were mostly due to reductions in zinc and vitamin A deficiencies, while anemia due to iron deficiency persisted and even increased. Interpretation This analysis is critical for informing and tracking the impact of policy and programmatic efforts to reduce micronutrient deficiencies, to advance the global nutrition agenda, and to achieve the Millennium Development Goals (MDGs). However, there remains an unmet need to invest in gathering frequent, nationally representative, high-quality micronutrient data as we renew our efforts to scale up nutrition, and as we enter the post-2015 development agenda. Funding Preparation of this manuscript was funded by Sight and Life. There was no funding involved in the study design, data collection, analysis, or decision to publish
Problems With Complex Actions
We consider Euclidean functional integrals involving actions which are not
exclusively real. This situation arises, for example, when there are -odd
terms in the the Minkowski action. Writing the action in terms of only real
fields (which is always possible), such terms appear as explicitly imaginary
terms in the Euclidean action. The usual quanization procedure which involves
finding the critical points of the action and then quantizing the spectrum of
fluctuations about these critical points fails. In the case of complex actions,
there do not exist, in general, any critical points of the action on the space
of real fields, the critical points are in general complex. The proper
definition of the function integral then requires the analytic continuation of
the functional integration into the space of complex fields so as to pass
through the complex critical points according to the method of steepest
descent. We show a simple example where this procedure can be carried out
explicitly. The procedure of finding the critical points of the real part of
the action and quantizing the corresponding fluctuations, treating the
(exponential of the) complex part of the action as a bounded integrable
function is shown to fail in our explicit example, at least perturbatively.Comment: 6+epsilon pages, no figures, presented at Theory CANADA
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Double-Duty Actions: Seizing Program and Policy Opportunities to Address Malnutrition in all its Forms
Actions to address different forms of malnutrition are typically managed by separate communities, policies, programmes, governance structures, and funding streams. In contrast, double duty actions, which aim to simultaneously tackle both undernutrition and problems of overweight, obesity and diet-related non-communicable diseases (DR-NCDs) have been proposed as a way to effectively address malnutrition in all its forms in a more holsitic way. This paper identifies ten double duty actions that have strong potential to reduce the risk of both undernutrition and obesity/DR-NCDs. It does so by : 1) summarizing evidence on common drivers of different forms of malnutrition; 2) documenting examples of unintended harm caused by some undernutrition-focused programmes on obesity/DR-NCDs; and 3) highlighting a few examples of first double duty actions undertaken to tackle multiple forms of malnutrition. We find that undernutrition and obesity/DR-NCDs are intrinsically linked through early life nutrition; dietary quality; food environments; and socioeconomic factors. There is some evidence that undernutrition-focused programs have raised risks of poor quality diets and obesity/DR-NCDs, especially in countries undergoing a rapid nutrition transition. The paper builds on this evidence to develop a framework to guide the design of double duty approaches and strategies, and defines the first steps needed to deliver them. With a clear package of double duty actions now identified, there is an urgent need to move forward with double duty actions to address malnutrition in all its forms
Optical Spectroscopy and Velocity Dispersions of Galaxy Clusters from the SPT-SZ Survey
We present optical spectroscopy of galaxies in clusters detected through the Sunyaev-Zel'dovich (SZ) effect with the South Pole Telescope (SPT). We report our own measurements of 61 spectroscopic cluster redshifts, and 48 velocity dispersions each calculated with more than 15 member galaxies. This catalog also includes 19 dispersions of SPT-observed clusters previously reported in the literature. The majority of the clusters in this paper are SPT-discovered; of these, most have been previously reported in other SPT cluster catalogs, and five are reported here as SPT discoveries for the first time. By performing a resampling analysis of galaxy velocities, we find that unbiased velocity dispersions can be obtained from a relatively small number of member galaxies (≾30), but with increased systematic scatter. We use this analysis to determine statistical confidence intervals that include the effect of membership selection. We fit scaling relations between the observed cluster velocity dispersions and mass estimates from SZ and X-ray observables. In both cases, the results are consistent with the scaling relation between velocity dispersion and mass expected from dark-matter simulations. We measure a ~30% log-normal scatter in dispersion at fixed mass, and a ~10% offset in the normalization of the dispersion-mass relation when compared to the expectation from simulations, which is within the expected level of systematic uncertainty
Double Duty Actions to Tackle All Forms of Malnutrition (P10-053-19).
Objectives: Background: Most countries are now experiencing a double burden of malnutrition (DBM), characterized by the coexistence of nutritional deficiencies (underweight, wasting, stunting, micronutrient deficiencies) and overweight/obesity and diet-related non-communicable diseases (obesity/DR-NCDs). Actions to address the two sides of the DBM are typically managed by separate communities, policies, programs, governance structures, and funding streams. Double duty actions, defined as actions that simultaneously address nutritional deficiencies and obesity/DR-NCDs, have been proposed as a win-win solution to tackling malnutrition in all its forms. The objective of the work was to explore opportunities-and make recommendations-for double duty actions to be delivered by programs and policies in key sectors such as health, social protection, education, and agriculture. Methods: We reviewed evidence on the known shared drivers of undernutrition and obesity/DR-NCDs; searched the literature to identify examples of undernutrition-focused programs (in the four sectors selected) that have inadvertently caused harm by increasing risks of obesity/DR-NCDs; and looked for additional information on measures that programs may have adopted to correct these problems following recognition of harm. Results: Undernutrition and obesity/DR-NCDs are intrinsically linked through four shared drivers: early life nutrition; dietary quality; food environments; and socioeconomic factors. Failure to adopt double duty actions in the past has caused harm. Examples from Latin America and Egypt show that some social cash/food transfer programs aimed at reducing poverty and undernutrition have led to deteriorations in diet quality (e.g., excess intakes of energy- fat- and sugar-dense and micronutrient-poor foods) and rises in obesity/DR-NCD risks. Realizing the harm, some of these programs pilot-tested successful corrective measures, thereby providing useful examples of early double duty actions. Conclusions: Leveraging the shared drivers of undernutrition and obesity/DR-NCDs through programs and policies delivered by the health, social protection, education, or agriculture sectors is possible and offers considerable opportunities for double duty actions and impacts on all forms of malnutrition. Funding Sources: CGIAR A4NH program led by IFPRI
Acute stress affects peripersonal space representation in cortisol stress responders.
Peripersonal space is the representation of the space near the body. It is implemented by a dedicated multisensory-motor network, whose purpose is to predict and plan interactions with the environment, and which can vary depending on environmental circumstances. Here, we investigated the effect on the PPS representation of an experimentally induced stress response and compared it to a control, non-stressful, manipulation. We assessed PPS representation in healthy humans, before and after a stressful manipulation, by quantifying visuotactile interactions as a function of the distance from the body, while monitoring salivary cortisol concentration. While PPS representation was not significantly different between the control and experimental group, a relation between cortisol response and changes in PPS emerged within the experimental group. Participants who showed a cortisol stress response presented enhanced visuotactile integration for stimuli close to the body and reduced for far stimuli. Conversely, individuals with a less pronounced cortisol response showed a reduced difference in visuotactile integration between the near and the far space. In our interpretation, physiological stress resulted in a freezing-like response, where multisensory-motor resources are allocated only to the area immediately surrounding the body
of the Enrollment Survey
through the Food and Nutrition Technical Assistance III Project (FANTA), managed by FHI 360. The contents are the responsibility of FHI 360 and do not necessarily reflect the views of USAID or the United States Government
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