403 research outputs found
OPERATIONAL PLANNING AND OPTIMIZATION OF SMALL DOMAIN SWARM DEFENSE STRATEGIES
This thesis considers the case of a drone defending a high-value target from a number of inbound attacking drones. The defending drone is equipped with short-range weapons and must destroy each of the attacking drones in the most efficient manner. This problem sits at the intersection of several open problems in applied mathematics, such as optimal motion planning in the presence of attrition, as well as solving a âtraveling salesman problemâ (TSP) with moving targets. The purpose of our research was to analyze this problem by decomposing it into the component problems and then presenting proof-of-concept solutions of each component. The primary results of this thesis include a modeling framework where optimization can be performed without requiring constraints; comparing the strengths of using different types of cost functions for optimization (e.g., minimizing the chance of high-value unit destruction versus a metric based on the path of the defender relative to attackers); and solving moving-target TSP in certain limits by mapping it onto standard TSP or using machine learning.Cruiser/ONRMajor, United States Marine CorpsApproved for public release. Distribution is unlimited
Quality Measurement in Wonderland: The Curious Case of a Dialysis Readmissions Measure
The standardized readmission ratio is a new quality measure for dialysis facilities that will affect public reporting and payment beginning in 2017. Like all quality measures affecting public reporting and payment, the standardized readmission ratio was vetted by a process that included a technical expert panel convened by the US Centers for Medicare and Medicaid Services, and, then, the National Quality Forum. Unlike previous measures, standardized readmission ratio followed a tortuous path that exposed problems in the development and endorsement process. Although it is acknowledged that processes in the dialysis facility can be improved to decrease readmissions, multiple objections to the implementation of the standardized readmission ratio measure existed. This review discusses the standardized readmission ratio measure and issues related to quality metric development that are important for the nephrology community to consider
Understanding the impact of âwish-grantingâ interventions on the health and wellbeing of children with life-threatening health conditions and their families: A systematic review
This is an accepted manuscript of an article published by SAGE in Journal of Child Health Care on 8 May 2021.
The accepted version of the publication may differ from the final published version.This review aimed to explore how wish-granting interventions impact on the health and wellbeing of children with life-threatening health conditions and their families, using any study design. Six electronic databases (Medline; PsycINFO; CINAHL; Embase; AMED; HMIC) were systematically searched to identify eligible research articles. Studies were critically appraised using a Mixed Methods Appraisal Tool. Findings were synthesised narratively. Ten papers were included, reporting studies conducted across five countries, published from 2007-2019. Study designs were diverse (four quantitative; two qualitative; four mixed method). Results indicated improvements to physical and mental health, quality of life, social wellbeing, resilience and coping for wish children, parents and siblings. In conclusion, wish-granting interventions can positively impact health and therefore, should not be discouraged; however, more research is needed to define and quantify the impact of wish-fulfillment and to understand how it can be maximized
Validation of the MEDFICTS dietary questionnaire: A clinical tool to assess adherence to American Heart Association dietary fat intake guidelines
BACKGROUND: Dietary assessment tools are often too long, difficult to quantify, expensive to process, and largely used for research purposes. A rapid and accurate assessment of dietary fat intake is critically important in clinical decision-making regarding dietary advice for coronary risk reduction. We assessed the validity of the MEDFICTS (MF) questionnaire, a brief instrument developed to assess fat intake according to the American Heart Association (AHA) dietary "steps". METHODS: We surveyed 164 active-duty US Army personnel without known coronary artery disease at their intake interview for a primary prevention cardiac intervention trial using the Block food frequency (FFQ) and MF questionnaires. Both surveys were completed on the same intake visit and independently scored. Correlations between each tools' assessment of fat intake, the agreement in AHA step categorization of dietary quality with each tool, and the test characteristics of the MF using the FFQ as the gold standard were assessed. RESULTS: Subjects consumed a mean of 36.0 ± 13.0% of their total calories as fat, which included saturated fat consumption of 13.0 ± 0.4%. The majority of subjects (125/164; 76.2%) had a high fat (worse than AHA Step 1) diet. There were significant correlations between the MF and the FFQ for the intake of total fat (r = 0.52, P < 0.0001) and saturated fat (r = 0.52, P < 0.0001). Despite these modest correlations, the currently recommended MF cutpoints correctly identified only 29 of 125 (23.3%) high fat (worse than AHA Step 1) diets. Overall agreement for the AHA diet step between the FFQ and MF (using the previously proposed MF score cutoffs of 0â39 [AHA Step 2], 40â70 [Step 1], and >70 [high fat diet]) was negligible (kappa statistic = 0.036). The MF was accurate at the extremes of fat intake, but could not reliably identify the 3 AHA dietary classifications. Alternative MF cutpoints of <30 (Step 2), 30â50 (Step 1), and >50 (high fat diet) were highly sensitive (96%), but had low specificity (46%) for a high fat diet. ROC curve analysis identified that a MF score cutoff of 38 provided optimal sensitivity 75% and specificity 72%, and had modest agreement (kappa = 0.39, P < 0.001) with the FFQ for the identification of subjects with a high fat diet. CONCLUSIONS: The MEDFICTS questionnaire is most suitable as a tool to identify high fat diets, rather than discriminate AHA Step 1 and Step 2 diets. Currently recommended MEDFICTS cutpoints are too high, leading to overestimation of dietary quality. A cutpoint of 38 appears to be providing optimal identification of patients who do not meet AHA dietary guidelines for fat intake
âPRi special edition: The intersections between public relations and neoliberalismâ â The road to nowhere: Re-examining activistsâ role in civil societies
The French sociologist Pierre Bourdieu (1977) argued that the presence of critical counter-voices and powers is a fundamental element of any genuine democracy. However, in Australia these counter-voices are increasingly marginalized and threatened by controversial laws that would limit the legal standing of conservation groups and the use of overseas donations for advocacy purposes based on the argument that âsystematic, well-fundedâ environmental campaigns are threatening the nationâs economic prosperity.
Drawing on social movement theory and Bourdieuâs theory of practice, this case study details the final months of the Save Beeliar Wetlands campaign in the lead up to the 2017 West Australian state election. The author challenges three common assumptions in the extant PR activism literature: The existence of activists in opposition to organizations and governments, the presence of a âzone of compromiseâ between activists and the organizations or governments whose actions they are opposing and the conceptualization of activists as homogenous entity.
Evolving into a colorful collective of over 35 local groups, five local councils and thousands of individuals, Beeliar Wetland Defenders successfully created an alternative narrative to the State and Federal Governmentsâ neoliberal agenda. Activists thereby contributed significantly to a change in leadership and the termination of a $1.9billion infrastructure project. This paper argues that activist groupsâ interventions in public debate perform a valuable societal voice as critical counter-voices in challenging established hierarchies and power relationships. However, in mounting and framing their arguments within the neoliberal framework, activist groups may also inadvertently reinforce this worldview
Iron Administration, Infection, and Anemia Management in CKD: Untangling the Effects of Intravenous Iron Therapy on Immunity and Infection Risk
dysfunction, increased exposure to infectious agents, loss of cutaneous barriers, comorbid conditions, and treatment-related factors (eg, hemodialysis and immunosuppressant therapy). Because iron plays a vital role in pathogen reproduction and host immunity, it is biologically plausible that intravenous iron therapy and/or iron deficiency influence infection risk in CKD. Available data from preclinical experiments, observational studies, and randomized controlled trials are summarized to explore the interplay between intravenous iron and infection risk among patients with CKD, particularly those receiving maintenance hemodialysis. The current evidence base, including data from a recent randomized controlled trial, suggests that proactive judicious use of intravenous iron (in a manner that minimizes the accumulation of nonâtransferrin-bound iron) beneficially replaces iron stores while avoiding a clinically relevant effect on infection risk. In the absence of an urgent clinical need, intravenous iron therapy should be avoided in patients with active infection. Although serum ferritin concentration and transferrin saturation can help guide clinical decision making about intravenous iron therapy, definition of an optimal iron status and its precise determination in individual patients remain clinically challenging in CKD and warrant additional study
Towards an understanding of contextual features that influence the linguistic formality of British Sign Language users
This paper seeks to understand linguistic formality through the identification and measurement of contextual features. Using an adapted sociometric methodology to combine systemic functional linguistics and sign linguistics, a survey identifies the elements of context that have an effect upon the level of linguistic formality employed by British Sign Language users. The responses of 51 participants are analysed in order to ascertain (i) the level of linguistic formality that would be employed in certain communicative scenarios, and (ii) the contextual features of these scenarios that have an influence on linguistic formality. The results obtained from this study posit that there is an overall agreement shared between British Sign Language users when choosing levels of linguistic formality based on broad contextual description alone. The people involved in the communication and their interpersonal relationships tend to be the biggest influence on the level of formality employed, whereas the topic of the interaction appears to show no significant influence upon linguistic formality on its own. This work contributes further evidence to the importance of studying language within communicative contexts and the importance of formality as an influential factor in linguistic production. It is hoped that this will encourage future studies to derive linguistic data of British Sign Language users, or indee
High school drinking mediates the relationship between parental monitoring and college drinking: A longitudinal analysis
<p>Abstract</p> <p>Background</p> <p>College drinking is a significant public health problem. Although parental monitoring and supervision reduces the risk for alcohol consumption among younger adolescents, few studies have investigated the impact of earlier parental monitoring on later college drinking. This study examined whether parental monitoring indirectly exerts a protective effect on college drinking by reducing high school alcohol consumption.</p> <p>Methods</p> <p>A longitudinal cohort of 1,253 male and female students, ages 17 to 19, attending a large, public, mid-Atlantic university was studied at two time points. First, data on high school parental monitoring and alcohol consumption were gathered via questionnaire during the summer prior to college entry. Second, during the first year of college, past-year alcohol consumption was measured via a personal interview. Multiple regression models tested the relationship between parental monitoring and past year alcohol use (i.e., number of drinks per drinking day).</p> <p>Results</p> <p>Holding constant demographics, SAT score, and religiosity, parental monitoring had a significant protective effect on both high school and college drinking level. However, the association between parental monitoring and college drinking level became non-significant once high school drinking level was held constant.</p> <p>Conclusion</p> <p>While parental monitoring did not directly influence college alcohol consumption, evidence for mediation was observed, whereby parental monitoring had an indirect influence on college drinking through reductions in high school drinking. Initiatives that promote effective parenting might be an important strategy to curb high-risk drinking among older adolescents. More research is needed to understand the nature and degree of parent-child communication that is necessary to extend the protective influence of parents into the college years.</p
Maternal substance use and integrated treatment programs for women with substance abuse issues and their children: a meta-analysis
<p>Abstract</p> <p>Background</p> <p>The rate of women with substance abuse issues is increasing. Women present with a unique constellation of risk factors and presenting needs, which may include specific needs in their role as mothers. Numerous integrated programs (those with substance use treatment and pregnancy, parenting, or child services) have been developed to specifically meet the needs of pregnant and parenting women with substance abuse issues. This synthesis and meta-analysis reviews research in this important and growing area of treatment.</p> <p>Methods</p> <p>We searched PsycINFO, MedLine, PubMed, Web of Science, EMBASE, Proquest Dissertations, Sociological Abstracts, and CINAHL and compiled a database of 21 studies (2 randomized trials, 9 quasi-experimental studies, 10 cohort studies) of integrated programs published between 1990 and 2007 with outcome data on maternal substance use. Data were summarized and where possible, meta-analyses were performed, using standardized mean differences (<it>d</it>) effect size estimates.</p> <p>Results</p> <p>In the two studies comparing integrated programs to no treatment, effect sizes for urine toxicology and percent using substances significantly favored integrated programs and ranged from 0.18 to 1.41. Studies examining changes in maternal substance use from beginning to end of treatment were statistically significant and medium sized. More specifically, in the five studies measuring severity of drug and alcohol use, the average effect sizes were 0.64 and 0.40, respectively. In the four cohort studies of days of use, the average effect size was 0.52. Of studies comparing integrated to non-integrated programs, four studies assessed urine toxicology and two assessed self-reported abstinence. Overall effect sizes for each measure were not statistically significant (<it>d </it>= -0.09 and 0.22, respectively).</p> <p>Conclusions</p> <p>Findings suggest that integrated programs are effective in reducing maternal substance use. However, integrated programs were not significantly more effective than non-integrated programs. Policy implications are discussed with specific attention to the need for funding of high quality randomized control trials and improved reporting practices.</p
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