DIRECT AND INDIRECT SPACE VECTOR MODULATED MATRIX CONVERTER

The Matrix Converter stands as an alternative in power conversion by directly connecting input terminals with output through bidirectional switches. It has low higher order harmonics as well as no sub-harmonics. Different modulation methods are available for matrix converter like space vector modulation method.  Direct and indirect space vector modulation methods are chosen here for the analysis of switching patterns of a three phase matrix converter.  Here, the effectiveness of two modulation methods is simulated in Matlab environment

Environmental health practitioners potentially play a key role in helping communities adapt to climate change

Abstract: Background: Vulnerable population groups in South Africa, especially those living in poverty, young children, women, the elderly and people with pre-existing diseases, are susceptible to new or exacerbated health threats resulting from climate change. Environmental Health Practitioners (EHPs) can play an important role in helping communities adapt to climate change health impacts, however, effective coordination of this requires further understanding of their roles in implementing climate change-related adaptation actions in communities. Methods: A cross-sectional survey using convenience sampling was undertaken at the January 2017 conference for EHPs hosted by the South African Institute of Environmental Health in Cape Town. All EHPs who attended the conference were invited to complete a study questionnaire that requested information on participant demographics, as well as climate change related-knowledge, practices and perceptions. Results: Majority of participating EHPs (n = 48; 72.8%) had received formal or informal training on climate change and health. Thirty-nine percent of EHPs indicated that they had a climate change and health-related committee / working group in their department, a policy or strategy (41.0%) and budget allocated for climate change and health-related work (51.5%). A total of 33.3% had participated in climate change-related projects. Majority (62.2%) of EHPs believed that they should play a supportive role in addressing climate change while 37.8% believed that EHPs should play a leading role. Conclusions: Recognising the need for raising awareness about climate change adaptation as well as implementing appropriate interventions to combat climate-related ill health effects, especially among vulnerable groups, EHPs are wellplaced to adopt significant roles in helping communities to adapt to climate change

Improving natural product research translation:from source to clinical trial

While great interest in health effects of natural product (NP) including dietary supplements and foods persists, promising preclinical NP research is not consistently translating into actionable clinical trial (CT) outcomes. Generally considered the gold standard for assessing safety and efficacy, CTs, especially phase III CTs, are costly and require rigorous planning to optimize the value of the information obtained. More effective bridging from NP research to CT was the goal of a September, 2018 transdisciplinary workshop. Participants emphasized that replicability and likelihood of successful translation depend on rigor in experimental design, interpretation, and reporting across the continuum of NP research. Discussions spanned good practices for NP characterization and quality control; use and interpretation of models (computational through in vivo) with strong clinical predictive validity; controls for experimental artefacts, especially for in vitro interrogation of bioactivity and mechanisms of action; rigorous assessment and interpretation of prior research; transparency in all reporting; and prioritization of research questions. Natural product clinical trials prioritized based on rigorous, convergent supporting data and current public health needs are most likely to be informative and ultimately affect public health. Thoughtful, coordinated implementation of these practices should enhance the knowledge gained from future NP research

Sigma-1 Agonist Binding in the Aging Rat Brain: a MicroPET Study with [11C]SA4503

Purpose: Sigma-1 receptor ligands modulate the release of several neurotransmitters and intracellular calcium signaling. We examined the binding of a radiolabeled sigma-1 agonist in the aging rat brain with positron emission tomography (PET). Procedures: Time-dependent uptake of [11C]SA4503 was measured in the brain of young (1.5 to 3 months) and aged (18 to 32 months) Wistar Hannover rats, and tracer-kinetic models were fitted to this data, using metabolite-corrected plasma radioactivity as input function. Results: In aged animals, the injected probe was less rapidly metabolized and cleared. Logan graphical analysis and a 2-tissue compartment model (2-TCM) fit indicated changes of total distribution volume (VT) and binding potential (BPND) of the tracer. BPND was reduced particularly in the (hypo)thalamus, pons, and medulla. Conclusions: Some areas showed reductions of ligand binding with aging whereas binding in other areas (cortex) was not significantly affected. © 2015 The Author(s

Improving natural product research translation: From source to clinical trial

While great interest in health effects of natural product (NP) including dietary supplements and foods persists, promising preclinical NP research is not consistently translating into actionable clinical trial (CT) outcomes. Generally considered the gold standard for assessing safety and efficacy, CTs, especially phase III CTs, are costly and require rigorous planning to optimize the value of the information obtained. More effective bridging from NP research to CT was the goal of a September, 2018 transdisciplinary workshop. Participants emphasized that replicability and likelihood of successful translation depend on rigor in experimental design, interpretation, and reporting across the continuum of NP research. Discussions spanned good practices for NP characterization and quality control; use and interpretation of models (computational through in vivo) with strong clinical predictive validity; controls for experimental artefacts, especially for in vitro interrogation of bioactivity and mechanisms of action; rigorous assessment and interpretation of prior research; transparency in all reporting; and prioritization of research questions. Natural product clinical trials prioritized based on rigorous, convergent supporting data and current public health needs are most likely to be informative and ultimately affect public health. Thoughtful, coordinated implementation of these practices should enhance the knowledge gained from future NP research

Coping with racism: a selective review of the literature and a theoretical and methodological critique

Abstract available at publisher's website