950 research outputs found
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Development of a composite-reinforced aluminum conductor
Fact sheet written for the Inventions and Innovation Program about a new composite-reinforced aluminum conductor for utility transmission and distribution. The millions of people affected by a blackout in the western US, Canada, and parts of Mexico in July 1996 had no idea the power outage was caused by overloaded transmission lines sagging low enough to touch trees. Millions of New Englanders affected by power outages during the 1997--98 winter probably weren't aware that accumulations of ice and snow on transmission lines had caused the lines to snap. Yet, these two examples illustrate the urgent need to begin upgrading this country's aging electrical-power distribution systems. A key step in this process lies in improving the weight and conductivity characteristics of utility transmission and distribution lines. Conventional conductors used for overhead transmission and distribution lines are comprised of aluminum strands of wire wrapped around a steel core. The aluminum serves as the electrical conductor, while the steel provides mechanical support. This hybrid design results in an excellent weight-to-conductivity ratio, but it also yields a heavier product, which requires stronger and more costly support structures and limits conductivity. W. Brandt Goldsworthy and Associates, Inc., of Torrance, California, is developing a new composite-reinforced aluminum conductor to replace aging steel-core lines. The new composite conductor is lighter, stronger, and carries a higher current capacity than traditional power lines. The technology has been designed primarily for domestic utility transmission and distribution systems. This application takes the highest priority as utility deregulation continues to increase the demand for direct-power access. Subsequent applications exist through opportunities in the industrial power, building wire, telecommunications and data transmission, and high-temperature superconductor markets. Similar applications overseas also represent tremendous potential, with growth projected at 10 times that of the United States market
THE IMPACT OF PROGRESS FEEDBACK ON SELF REGULATED GOALS AND PERFORMANCE OF POSTGRADUATE RESEARCH STUDENTS
The demand for a continuous consideration of postgraduate supervision has risen because of the various problems reported in numerous studies, such as the high rate of dissatisfaction and attrition, supervisorsâ inadequate knowledge about practical aspects of candidature, and unsatisfactory levels in obtaining feedback about studentsâ performance and progress. These studies indicated that giving and receiving constructive and ongoing feedback between supervisors and students plays an essential role in identifying both parties concerns. For postgraduate research students, the nature of their task requires them to work more independently. Thus, self-regulating learning becomes important, particularly at the early stages of the study where students start to set their study goals, and the social support of the supervisor becomes in need. Self-regulating learning is the process of setting a goal, employing goal-directed actions, monitoring strategies and adjusting them to ensure success. This paper discusses the effect of supervisor feedback on the studentâs self-regulation based on a review of the literature of self-regulation theory, and how receiving positive or negative feedback may affect studentâs goal setting and performance during the postgraduate study. Article visualizations
Influence of beta-blockers on endothelial function: A meta-analysis of randomized controlled trials
Background: Endothelial dysfunction (ED) frequently precedes cardiovascular diseases (CVD) and is a well-established risk factor of major adverse cardiac events. Beta-blockers are the fundamental drugs used in CVD treatment.
Methods: A systematic literature search for randomized controlled trials investigating influence of beta-blockers on endothelial function assessed by flow-mediated dilation (FMD) was performed in the PubMed and Cochrane Databases.
Results: Sixteen full-text studies involving a total of 1,273 patients were included in the final analysis. The mean age of participating patients ranged from 44.9 to 63.2 years, the follow-up duration from 1 to 12 months. The comparison of FMD change between the beta-blockers and placebo groups showed a statistically significant effect of beta-blockers on endothelial function (mean difference [MD] 0.83; 95% confidence interval [CI] 0.11â1.55; p = 0.02). Third generation beta-blockers improved FMD in a statistically significant manner compared with second generation beta-blockers (MD 1.65; 95% CI 0.17â3.11; p = 0.03). Beta-blockers gave an FMD change similar to that obtained with angiotensin receptor blockers (ARB), calcium channel blockers (CCB) or hydrochlorothiazide. The FMD value in the beta-blocker group was significantly lower compared with the group treated with angiotensin converting enzyme inhibitors (ACEI) (MD â0.79; 95% CI â1.37â(â0.21); p = 0.008) and higher than in the ivabradine group (1.6 ± 3.61 vs â0.3 ± 1.66; p = 0.02).
Conclusions: Beta-blockers improve the endothelial function compared with placebo. MoreÂover, third generation beta-blockers improve FMD values significantly better than the second generation ones. Beta-blockers had similar effect on endothelial function as did ARB, CCB or diuretics. However, the beneficial effect of beta-blockers was lower when confronted with ACEI
The Role of Metamodeling in Systems Development
Software systems developers are encountering different challenges as systems become increasingly complex due to numerous customers' needs that lead to a system with rich functionalities to be delivered within a short schedule. Developers also have to manage a variety of implementation methods, design techniques, and development processes. Researchers proposed âlanguagesâ as a solution to these problems. Meta-modeling is a method for defining the abstract syntax of a language. It makes the development of a language simpler allowing the designers to directly map the classes identified in domain analysis to classes in the meta-model. The meta-model expresses what models include such as concepts, relationships between them, and maybe the rules of how these concepts can be interrelated. This article presents an overview of the role and importance of meta-models in system development and their relationship with modeling languages. It highlights different aspects of metamodels standards, categories, and challenges in the research of meta-modeling
Testing a model of minority identity achievement, identity affirmation, and psychological well-being among ethnic minority and sexual minority individuals
How is social identity related to psychological well-being among minority individuals? Drawing on developmental models of identity formation (e.g., Erikson, 1968) and on Social Identity Theory (Tajfel & Turner, 1979), we tested a conceptual model examining links between two key aspects of social identity and psychological well-being. We proposed that the association between identity achievement (exploring and understanding the meaning of one\u27s identity) and psychological well-being is mediated by identity affirmation (developing positive feelings and a sense of belonging to one\u27s social group). Across three studies, including ethnic minority high school students (Study 1), ethnic minority college students (Study 2) and lesbian and gay male adults (Study 3), we found strong support for the model. Results suggest that the process of exploring and understanding one\u27s minority identity can serve as an important basis for developing positive feelings toward and an enhanced sense of attachment to the group, which can in turn confer psychological benefits for minority individuals. Implications and directions for future research are discussed
Social Services for Sexual Minority Youth: Preferences for What, Where, and How Services are Delivered
As part of an internet-based study to investigate experiences of sexual minority youth in the U.S., 544 youth, ages 14-19, were surveyed about their need for services, where they preferred to receive these services, and their preferred method of service delivery. The survey was anonymous and youth were recruited from LGBTQ-specific listservs and venues as well as through social networking sites as a way of reaching youth often not represented in LGBTQ surveys. Youth highly endorsed many types of services, settings, and modes of delivery. Some subgroup differences emerged. Transgender youth and those uncertain about their gender identity expressed stronger interest than others in services to address stress, family issues, and self-defense, and in receiving support and guidance from LGBTQ adults. Few differences in service preferences along demographic lines such as race/ethnicity emerged; however, African American youth were more likely than others to prefer services offered in a place of worship. Contrary to predictions, geographic and community variables were not related to service type, delivery format, or location preferences
Optimal aNtiplatelet pharmacotherapy guided by bedSIDE genetic or functional TESTing in elective PCI patients: A pilot study: ONSIDE TEST pilot
Background: Dual antiplatelet therapy (DAPT) is recommended after elective percutaneous coronary intervention (PCI) in stable coronary artery disease (SCAD) patients; however, still one-third of patients do not obtain adequate platelet inhibition that may result in increased cardiovascular risk. The aim of the ONSIDE TEST study is to evaluate the clinical impact of point-of-care genotyping- and platelet function-based personalized dual antiplatelet strategies in SCAD individuals undergoing PCI.
Methods: Fifty patients were randomized to one of the three study arms: 1) genotyping, 2) platelet function testing (PFT) and 3) control. Patients were tested with point-of-care Spartan RX CYP2C19 System (group 1) and VerifyNow P2Y12 assay (group 2). In cases of inadequate response to clopidogrel, a loading dose of prasugrel was administered before PCI. The main clinical endpoint is the incidence of periprocedural myocardial injury (PMI).
Results: Five (32%) patients in the genotyping arm and two (13%) in the in the PFT arm were identi-fied as poor clopidogrel metabolizers. The periprocedural platelet reactivity was significantly lower in the genotyping (80 ± 49.0 PRU) and PFT (36.5 ± 47 PRU) arms as compared to the control arm (176 ± 67.8 PRU), p = 0.01 and p = 0.03, respectively. PMI appeared in 17 (37%) patients of the entire study population.
Conclusions: Personalized DAPT results in an improved platelet inhibition. Apart from genotyping and aggregometry, it is feasible to integrate into everyday clinical practice PMI rates which are relevant when comparing different strategie
The National Childrens Study: An Introduction and Historical Overview
The National Childrenâs Study (NCS) was an ambitious attempt to map childrenâs health and development in a large representative group of children in the United States. In this introduction, we briefly review the background of the NCS and the history of the multiple strategies that were tested to recruit women and children. Subsequent articles then detail the protocols and outcomes of 4 of the recruitment strategies. It is hoped that lessons learned from these attempts to define a study protocol that could achieve the initial aims of the NCS will inform future efforts to conceptualize and execute strategies to provide generalizable insights on the longitudinal health of our nationâs children
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The Pediatrician and Disaster Preparedness
Recent natural disasters and events of terrorism and war have heightened society's recognition of the need for emergency preparedness. In addition to the unique pediatric issues involved in general emergency preparedness, several additional issues related to terrorism preparedness must be considered, including the unique vulnerabilities of children to various agents as well as the limited availability of age- and weight-appropriate antidotes and treatments. Although children may respond more rapidly to therapeutic intervention, they are at the same time more susceptible to various agents and conditions and more likely to deteriorate if not monitored carefully.The challenge of dealing with the threat of terrorism, natural disasters, and public health emergencies in the United States is daunting not only for disaster planners but also for our medical system and health professionals of all types, including pediatricians. As part of the network of health responders, pediatricians need to be able to answer concerns of patients and families, recognize signs of possible exposure to a weapon of terror, understand first-line response to such attacks, and sufficiently participate in disaster planning to ensure that the unique needs of children are addressed satisfactorily in the overall process. Pediatricians play a central role in disaster and terrorism preparedness with families, children, and their communities. This applies not only to the general pediatrician but also to the pediatric medical subspecialist and pediatric surgical specialist. Families view pediatricians as their expert resource, and most of them expect the pediatrician to be knowledgeable in areas of concern. Providing expert guidance entails educating families in anticipation of events and responding to questions during and after actual events. It is essential that pediatricians educate themselves regarding these issues of emergency preparedness. For pediatricians, some information is currently available on virtually all of these issues in recently produced printed materials, at special conferences, in broadcasts of various types, and on the Internet. However, selecting appropriate, accurate sources of information and determining how much information is sufficient remain difficult challenges. Similarly, guidance is needed with respect to developing relevant curricula for medical students and postdoctoral clinical trainees
OCULUS study: Virtual reality-based education in daily clinical practice
Background: Atrial fibrillation (AF) is associated with high risk of stroke and other thromboembolic complications. The OCULUS study aimed to evaluate the effectiveness of the three-dimensional (3D) movie in teaching patients about the consequences of AF and pharmacological stroke prevention.Â
Methods: The study was based on a questionnaire and included 100 consecutive patients (38% women, 62% with AF history). Using the oculus glasses and a smartphone, a 3D movie describing the risk of stroke in AF was shown. Similar questions were asked immediately after, 1 week and 1 year after the projection.Â
Results: Before the projection 22/100 (22.0%) declared stroke a consequence of AF, while immediately after 83/100 (83.0%) (p < 0.0001) patients declared this consequence. Seven days after, stroke as AF consequence was chosen by 74/94 (78.7%) vs. 22/94 (23.4%) when compared to the baseline knowledge; p < 0.0001, a similar trend was also observed in 1-year follow-up (64/90 [71.1%] vs. 21/90 [23.3%]; p < 0.0001). Before the projection 88.3% (83/94) patients responded, that drugs may reduce the risk of stroke, and after 1 week the number of patients increased to (94/94 [100%]; p = 0.001). After 1 year 87/90 (96.7%) answered that drugs may diminish the risk of stroke (p = 0.02 in comparison to the baseline survey 78/90 [86.7%]). Use of oral anticoagulation to reduce the risk of stroke was initially chosen by 66/94 (70.2%), by 90/94 (95.7%; p < 0.0001) 7 days after and by 83/90 (92.2%; p < 0.0001) 1 year after.Â
Conclusions: 3D movie is an effective tool in transferring knowledge about the consequences of AF and the pivotal role of oral anticoagulation in stroke prevention.
Trial registration: ClinicalTrials.gov, NCT03104231. Registered on 28 March 2017
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