345 research outputs found
Effects of Combined Opioids on Pain and Mood in Mammals
The authors review the opioid literature for evidence of increased analgesia and reduced adverse side effects by combining mu-opioid-receptor (MOR) agonists, kappa-opioid-receptor (KOR) agonists, and nonselective low-dose-opioid antagonists (LD-Ant). We tested fentanyl (MOR agonist) and spiradoline (KOR agonist), singly and combined, against somatic and visceral pain models. Combined agonists induced additive analgesia in somatic pain and synergistic analgesia in visceral pain. Other investigators report similar effects and reduced tolerance and dependence with combined MOR agonist and KOR agonist. LD-Ant added to either a MOR agonist or KOR agonist markedly enhanced analgesia of either agonist. In accordance with other place-conditioning (PC) studies, our PC investigations showed fentanyl-induced place preference (CPP) and spiradoline-induced place aversion (CPA). We reduced fentanyl CPP with a low dose of spiradoline and reduced spiradoline CPA with a low dose of fentanyl. We propose combined MOR agonist, KOR agonist, and LD-Ant to produce superior analgesia with reduced adverse side effects, particularly for visceral pain
Fentanyl And Spiradoline Interactions In A Place-Conditioning Black-White Shuttle-Box
Rats were trained for multiple sessions in a place-conditioning shuttle-box to explore motivational interactions of mu and kappa opioid agonists, specifically fentanyl reward and spiradoline aversion. In Phase 1, groups of rats received various doses of mu or kappa agonists, or placebo, testing for preference or aversion. Group A always received saline SC before 15-minute sessions. Group B received fentanyl SC (0.003, 0.006, 0.012 mg/kg), Group C received low and medium doses of agonists SC, and Group D received spiradoline (0.3, 0.6, 1.2 mg/kg) SC during Training Sessions 1-4, rats being restricted to the drug-associated compartment. Rats received saline when restricted to the placebo-associate compartment and on test days with access to both shuttle-box compartments. In Phase 2 of the study, Training Session 5, Combinations of mu and kappa agonists were substituted in Groups B, C, and D. Dose-related preference to fentanyl and aversion to spiradoline occurred during Test Sessions 1-4. During Test Session 5, fentanyl preference in Group B was suppressed by spiradoline, rats in Group C had a saline-like response to combined agonists, and spiradoline aversion in Group D was attenuated by fentanyl. These findings suggest that combined doses of mu and kappa agonists, while additive for antinociception, offset the rewarding and punishing effects of each other
High-performance Si microwire photovoltaics
Crystalline Si wires, grown by the vapor–liquid–solid (VLS)
process, have emerged as promising candidate materials for lowcost, thin-film photovoltaics. Here, we demonstrate VLS-grown Si microwires that have suitable electrical properties for high-performance photovoltaic applications, including long minority-carrier diffusion lengths (L_n » 30 µm) and low surface recombination velocities (S « 70 cm·s^(-1)). Single-wire radial p–n junction solar cells were fabricated with amorphous silicon and silicon nitride
surface coatings, achieving up to 9.0% apparent photovoltaic efficiency, and exhibiting up to ~600 mV open-circuit voltage with over 80% fill factor. Projective single-wire measurements and optoelectronic simulations suggest that large-area Si wire-array solar cells have the potential to exceed 17% energy-conversion efficiency, offering a promising route toward cost-effective crystalline Si photovoltaics
Si microwire-array solar cells
Si microwire-array solar cells with Air Mass 1.5 Global conversion efficiencies of up to 7.9% have been fabricated using an active volume of Si equivalent to a 4 μm thick Si wafer. These solar cells exhibited open-circuit voltages of 500 mV, short-circuit current densities (J_(sc)) of up to 24 mA cm^(-2), and fill factors >65% and employed Al_2O_3 dielectric particles that scattered light incident in the space between the wires, a Ag back reflector that prevented the escape of incident illumination from the back surface of the solar cell, and an a-SiN_x:H passivation/anti-reflection layer. Wire-array solar cells without some or all of these design features were also fabricated to demonstrate the importance of the light-trapping elements in achieving a high J_(sc). Scanning photocurrent microscopy images of the microwire-array solar cells revealed that the higher J_(sc) of the most advanced cell design resulted from an increased absorption of light incident in the space between the wires. Spectral response measurements further revealed that solar cells with light-trapping elements exhibited improved red and infrared response, as compared to solar cells without light-trapping elements
Cognitive-Behavioral Treatment for Posttraumatic Stress Disorder in Children and Adolescents
A number of Cognitive Behavioral Therapy (CBT) approaches are available for treating child and adolescent posttraumatic stress disorder (PTSD). Similar to other CBT treatments, particularly those for anxiety disorders, these treatments all include common elements (e.g., psychoeducation, relaxation and affective modulation skills, exposure). The goals of this review are to: 1) delineate common elements in CBT approaches for treating child and adolescent PTSD; 2) provide a detailed review of two CBT approaches with substantial evidence of effectiveness; and 3) describe “Promising Practices,” in the area of CBT approaches to treating child and adolescent PTSD. The two treatments reviewed in detail are Trauma-focused Cognitive Behavioral Therapy (TF-CBT) and Cognitive Behavioral Intervention for Trauma in Schools (CBITS). For these treatments, we describe the research evidence to date, specific elements of the treatment model, and discuss implementation and cultural considerations. In the “Promising Practices” section, other CBT approaches are reviewed that include many of the common elements; however, these approaches have accumulated less evidence of effectiveness to date. Research on CBT approaches to treating PTSD is ongoing, with a growing focus on explicit consideration of the multiple systems in which youth exposed to trauma are involved, and ways to better address co-occurring difficulties (e.g. serious behavior problems, substance use). Future directions for the field are discussed. These include further study of promising practices, cultural applicability of CBT approaches to treating PTSD, and strategies to enhance implementation and dissemination efforts to improve access to high-quality, evidence-based care for children and adolescents with PTSD
Child abuse, child protection and disabled children : a review of recent research
This paper reports the results of a scoping study which reviewed research about child abuse, child protection and disabled children published in academic journals between 1996 - 2009. The review was conducted using a five stage method for scoping studies. Several studies have revealed a strong association between disability and child maltreatment, indicating that disabled children are significantly more likely to experience abuse than their non-disabled peers. Those with particular impairments are at increased risk. There is evidence that the interaction of age, gender and/or socio-cultural factors with impairment results in different patterns of abuse to those found among non-disabled children although the reasons for this require further examination. It appears that therapeutic services and criminal justice systems often fail to take account of disabled children's needs and heightened vulnerability. In Britain, little is known about what happens to disabled children who have been abused and how well safeguarding services address their needs. Very few studies have sought disabled children's own accounts of abuse or safeguarding. Considerable development is required, at both policy and practice level, to ensure that disabled children's right to protection is upheld. The paper concludes by identifying a number of aspects of the topic requiring further investigation
Survey of Nutrition Education Among Medical Students
Introduction: The current literature regarding both specific interventions and the current level of nutrition education in the United States is scarce. The purpose of this paper is to provide medical student perspectives on both the degree and necessity of nutrition education during medical school.
Methods: Medicine in Motion (MM) is a non-profit student-run organization founded in 2018 that aims to address burnout in medicine through physical activity, community service, and philanthropy. MM issued a survey to nine of its chapters in January 2021 to assess a range of topics including burnout, physical activity, and nutrition education.
Results: Of 5500 invited students, 1182 (21.5%) responded. An average of 1.2 hours of formal nutrition education per year was reported across all participants. Students who received any degree of nutritional education reported 2.9 hours per year. Most students (57.6%) had not participated in a medical school course that provided formal education in nutrition. Of those that did participate in a nutrition course (42.4%), the course was required for 84.7% of students and the majority (80.1%) received 0-10 hours of nutrition education. Most respondents (88.7%) reported that requiring formal nutrition education should be a graduation requirement and a similar number of students (89.3%) believe medical students should receive formal training on nutrition counseling for patients. The majority (93.3%) of students either somewhat or strongly agreed that understanding the effects of nutrition/eating decisions on the human body is critical to maximizing patient care.
Conclusion: Based on prior studies, physicians feel underprepared to provide nutrition counseling to their patients despite the large role poor diet plays in the burden of disease. Most medical students in this cohort believe that understanding nutrition is vital to maximize patient care. Funding and curricular changes should be allocated towards expanding the nutrition curriculum across U.S. medical schools
Test Results From a Direct Drive Gas Reactor Simulator Coupled to a Brayton Power Conversion Unit
The Brayton Power Conversion Unit (BPCU) located at NASA Glenn Research Center (GRC) in Cleveland, OH is a closed cycle system incorporating a turboaltemator, recuperator, and gas cooler connected by gas ducts to an external gas heater. For this series of tests, the BPCU was modified by replacing the gas heater with the Direct Drive Gas heater or DOG. The DOG uses electric resistance heaters to simulate a fast spectrum nuclear reactor similar to those proposed for space power applications. The combined system thermal transient behavior was the focus of these tests. The BPCU was operated at various steady state points. At each point it was subjected to transient changes involving shaft rotational speed or DOG electrical input. This paper outlines the changes made to the test unit and describes the testing that took place along with the test results
Essentials in Accident and Emergency Medicine Radiation Injury: Response and Treatment
The discovery of radiation has enabled great healthcare advances as well as catastrophic injury. This paper reviews major historical incidents of public radiation exposure and the evolution of standards affecting today’s public and health care workers. Current patient care and response assessment to radiation exposure are reviewed. The strengths of modern radiation therapy and the need for continuous process improvements to ensure optimal patient care and secure safe environments are identified. The discovery of radiation has brought significant scientific achievements as well as catastrophic injury
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