354 research outputs found

    Paper Session III-C - Reaction Control System Propellant Trade Study: An Application of the Analytic Hierarchy Process

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    Decision making is often difficult because tradeoffs must be made among competing objectives. In order to make tradeoffs, decision makers must be able to evaluate and measure each aspect of the decision - some quantitative, some qualitative, some very important, and some not so important. Uncertainties and competing interest groups also add to the complexity of decision making. The analytic hierarchy process (AHP) is a multicriterion (or mult (objective) decision support methodology. AHP makes it possible for decision makers to deal with both tangible and intangible factors. Data, thoughts, and intuition are organized in a logical, hierarchical structure. Decision makers can express their understanding and experience with pairwise comparisons about the relative importance or preference of all relevant factors. AHP allows for revision for sensitivity analyses. The results of an AHP are easily tested for sensitivities to changes in assumptions and judgments. Current Space Shuttle hypergolic propellant systems servicing is extremely hazardous and performed at three different facilities at the Kennedy Space Center (KSC). These facilities are the Orbiter Processing Facility (OPF), the Hypergolic Maintenance Facility (HMF), and Launch Complex 39 (LC-39). Propellant systems servicing in the OPF and at LC-39 must be scheduled with processing of other Space Shuttle systems. Serial processing time is incurred in any facility with hazardous operations. Alternative propellants were considered in a trade study for use on a proposed reaction control system (PCS). Specifically hydrogen peroxide (^Cy/rocket propellant 1 (RP-1) were analyzed versus the currently used nitrogen tetroxide (^O^/monomethylhydrazine (MMH). The purpose of the trade study was to identify impacts or potential savings in facilities, equipment, and processing tasks for the RCS. AHP was used as a significant decision making aid in obtaining the study results

    Just Because (Most) Hospitals Are Publishing Charges Does Not Mean Prices Are More Transparent

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    Background: The Centers for Medicare and Medicaid Services (CMS) recently mandated that all hospitals publish their charge description masters (CDMs) online, in a machine-readable format, by January 1, 2019. In addition, CMS recommended that CDM data be made available in a manner that was consumer friendly and accessible to patients. Objective: This study aimed to (1) examine all hospitals across the state of Pennsylvania to understand policy compliance and (2) use established metrics to measure accessibility and consumer friendliness of posted CDM data. Methods: A cross-sectional analysis was conducted to quantify hospital website compliance with the recent CMS policies requiring hospitals to publish their CDM. Data were collected from all Pennsylvania hospital websites. Consumer friendliness was assessed based on searchability, number of website clicks to data, and supplemental educational materials accompanying CDMs such as videos or text. Results: Most hospitals (189/234, 80.1%) were compliant, but significant variation in data presentation was observed. The mean number of website clicks to the CDM was 3.7 (SD 1.3; range: 1-8). A total of 23.1% of compliant hospitals provided no supplemental educational material with their CDM. Conclusions: Although disclosure of charges has improved, the data may not be sufficient to meaningfully influence patient decision making

    Sulfur analysis of Bolu-Mengen lignite before and after microbiological treatment using reductive pyrolysis and gas chromatography/mass spectrometry

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    Atmospheric pressure-temperature programmed reduction coupled with on-line mass spectrometry (AP-TPR/MS) is used for the first time on microbiologically treated coal samples as a technique to monitor the degree of desulfurization of the various sulfur functionalities. The experimental procedure enables the identification of both organic and inorganic sulfur species present in the coal matrix. A better insight in the degradation of the coal matrix and the accompanying processes during the AP-TPR experiment is obtained by a quantitative differentiation of the sulfur. The determination of the sulfur balance for the reductive pyrolysis gives an overview of the side reactions and their relative contribution in the total process. The volatile sulfur species are unambiguously identified using AP-TPR off-line coupled with gas chromatography/mass spectrometry (GC/MS). In this way, fundamental mechanisms and reactions that occur during the reductive pyrolysis could be quantified, explaining the differences in AP-TPR recoveries. Therefore, this study gives a clearer view on the possibilities and limitations of AP-TPR as a technique to monitor sulfur functionalities in coal

    HIV-Related Knowledge and Practices among Asian and African Migrants Living in Australia: Results from a Cross-Sectional Survey and Qualitative Study

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    Australian HIV notification rates are higher for people born in Northeast Asia, Southeast Asia and sub-Saharan Africa compared to Australian-born people. The Migrant Blood-Borne Virus and Sexual Health Survey represents the first attempt to build the national evidence base regarding HIV knowledge, risk behaviors and testing among migrants in Australia. To inform survey development, preliminary qualitative research was conducted with a convenience sample of n = 23 migrants. A survey was developed with reference to the qualitative data and existing survey instruments. Non-probability sampling of adults born in Northeast Asia, Southeast Asia and sub-Saharan Africa was undertaken (n = 1489), and descriptive and bivariate analyses of data were conducted. Knowledge of pre-exposure prophylaxis was low (15.59%), and condom use at last sexual encounter was reported by 56.63% of respondents engaging in casual sex, and 51.80% of respondents reported multiple sexual partners. Less than one-third (31.33%) of respondents reported testing for any sexually transmitted infection or blood-borne virus in the previous two years and, of these, less than half (45.95%) tested for HIV. Confusion surrounding HIV testing practices was reported. These findings identify policy interventions and service improvements critically needed to reduce widening disparities regarding HIV in Australia

    Mothers of Soldiers in Wartime: A National News Narrative

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    National news media represent mothers of US combat soldiers in the Iraq War as archetypal good mothers, that is, mothers who continue their maternal work even after their children are deployed. However, not all mothers are depicted as the archetypal patriotic mother, i.e., a good mother who is also stoic and silent about the war and her child\u27s role in it. Mothers of soldiers are portrayed as good mothers who sometimes also voice their attitudes about the war effort. The maternal attitudes ranged from complete support for the war to opposition to the war but support for the soldiers. The findings suggest a picture of wartime motherhood that is more nuanced than the historical image of the patriotic mother suggests

    Crystal structure of dichlorido(4,11-dimethyl-1,4,8,11-tetraazabicyclo[6.6.2]hexadecane)iron(III) hexafluoridophosphate

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    The title compound, [FeCl₂(C₁₄H₃₀N₄)]PF₆, contains Fe³⁺ coordinated by the four nitro­gen atoms of an ethyl­ene cross-bridged cyclam macrocycle and two cis chloride ligands in a distorted octa­hedral environment. In contrast to other similar compounds this is a monomer. Inter­molecular C-H...Cl inter­actions exist in the structure between the complex ions. Comparison with the mononuclear Fe²⁺ complex of the same ligand shows that the smaller Fe³⁺ ion is more fully engulfed by the cavity of the bicyclic ligand. Comparison with the μ-oxido dinuclear complex of an unsubstituted ligand of the same size demonstrates that the methyl groups of 4,11-dimethyl-1,4,8,11-tetra­aza­bicyclo­[6.6.2]hexa­decane prevent dimerization upon oxidation

    The Building America Industrialized Housing Partnership (BAIHP)

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    The Building America Industrialized Housing Partnership (BAIHP) is one of five competitively selected U.S. DOE Building America teams and began work on 9/1/99. BAIHP focuses on improving the energy efficiency, durability and indoor air quality in manufactured homes. Team members, Cavalier Homes, Fleetwood Homes, Palm Harbor Homes, Southern Energy Homes, and manufacturers in the Super Good Cents/Natural Choice program produce over 100,000 manufactured homes/yr currently. In addition, the BAIHP team provides technical assistance to about 30 site builders and modular home manufacturers including Habitat for Humanity affiliates throughout the nation. BAIHP is also charged with enhancing the energy efficiency and learning environment in portable classrooms in the northwestern states of WA, OR and ID. This paper summarizes the multifaceted work being performed by BAIHP and provides specific data on 310 homes constructed in the Gainesville FL area with technical assistance from Florida Home Energy and Resources Organization. The paper also summarizes typical causes and cures for moisture problems in manufactured homes

    Heart failure during the COVID-19 pandemic: clinical, diagnostic, management, and organizational dilemmas

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    The coronavirus 2019 (COVID-19) infection pandemic has affected the care of patients with heart failure (HF). Several consensus documents describe the appropriate diagnostic algorithm and treatment approach for patients with HF and associated COVID-19 infection. However, few questions about the mechanisms by which COVID can exacerbate HF in patients with high-risk (Stage B) or symptomatic HF (Stage C) remain unanswered. Therefore, the type of HF occurring during infection is poorly investigated. The diagnostic differentiation and management should be focused on the identification of the HF phenotype, underlying causes, and subsequent tailored therapy. In this framework, the relationship existing between COVID and onset of acute decompensated HF, isolated right HF, and cardiogenic shock is questioned, and the specific management is mainly based on local hospital organization rather than a standardized model. Similarly, some specific populations such as advanced HF, heart transplant, patients with left ventricular assist device (LVAD), or valve disease remain under investigated. In this systematic review, we examine recent advances regarding the relationships between HF and COVID-19 pandemic with respect to epidemiology, pathogenetic mechanisms, and differential diagnosis. Also, according to the recent HF guidelines definition, we highlight different clinical profile identification, pointing out the main concerns in understudied HF populations.© 2022 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of European Society of Cardiology

    Higher doses of loop diuretics limit uptitration of angiotensin converting enzyme inhibitors in patients with heart failure and reduced ejection fraction

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    Background: Loop diuretics are frequently prescribed to patients with heart failure and reduced ejection fraction (HFrEF) for the treatment of congestion; however, they might hamper uptitration of inhibitors of the renin–angiotensin system. Methods: Loop diuretic dose at baseline was recorded in 2338 patients with HFrEF enrolled in BIOSTAT-CHF, an international study of HF patients on loop diuretic therapy who were eligible for uptitration of angiotensin-converting enzyme inhibitors (ACEi)/mineralocorticoid receptor antagonists (MRA). The association between loop diuretic dose and uptitration of ACEi/MRA to percentage of target dose was adjusted for a previously published model for likelihood of uptitration and a propensity score. Results: Baseline median loop diuretic dose was 40 [40–100] mg of furosemide or equivalent. Higher doses of loop diuretics were associated with higher NYHA class and higher levels of NT-proBNP, more severe signs and symptoms of congestion, more frequent MRA use, and lower doses of ACEi reached at 3 and 9 months (all P < 0.01). After propensity adjustment, higher doses of loop diuretics remained significantly associated with poorer uptitration of ACEi (Beta per log doubling of loop diuretic dose: − 1.66, P = 0.021), but not with uptitration of MRAs (P = 0.758). Higher doses of loop diuretics were independently associated with an increased risk of all-cause mortality or HF hospitalization [HR per doubling of loop diuretic dose: 1.06 (1.01–1.12), P = 0.021]. Conclusions: Higher doses of loop diuretics limited uptitration of ACEi in patients with HFrEF and were associated with a higher risk of death and/or HF hospitalization, independent of their lower likelihood of uptitration and higher baseline risk. Graphic abstract: This figure was created with images adapted from Servier Medical Art licensed under a Creative Commons Attribution 3.0[Figure not available: see fulltext.]

    A Modeling Framework to Describe the Transmission of Bluetongue Virus within and between Farms in Great Britain

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    Recently much attention has been given to developing national-scale micro-simulation models for livestock diseases that can be used to predict spread and assess the impact of control measures. The focus of these models has been on directly transmitted infections with little attention given to vector-borne diseases such as bluetongue, a viral disease of ruminants transmitted by Culicoides biting midges. Yet BT has emerged over the past decade as one of the most important diseases of livestock.We developed a stochastic, spatially-explicit, farm-level model to describe the spread of bluetongue virus (BTV) within and between farms. Transmission between farms was modeled by a generic kernel, which includes both animal and vector movements. Once a farm acquired infection, the within-farm dynamics were simulated based on the number of cattle and sheep kept on the farm and on local temperatures. Parameter estimates were derived from the published literature and using data from the outbreak of bluetongue in northern Europe in 2006. The model was validated using data on the spread of BTV in Great Britain during 2007. The sensitivity of model predictions to the shape of the transmission kernel was assessed.The model is able to replicate the dynamics of BTV in Great Britain. Although uncertainty remains over the precise shape of the transmission kernel and certain aspects of the vector, the modeling approach we develop constitutes an ideal framework in which to incorporate these aspects as more and better data become available. Moreover, the model provides a tool with which to examine scenarios for the spread and control of BTV in Great Britain
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