167 research outputs found
Investigation of a decentralised control strategy for grid frequency support from DC microgrids
DC microgrids are capable of integrating and coordinating distributed energy resources into power systems, along with providing services to the wider system e.g. balancing, frequency support, demand response, etc. This paper investigates the capability of DC microgrids providing grid frequency support, for the GB Enhanced Frequency Response service. In this study, photovoltaic generation, energy storage, and load, form the DC microgrids. The control strategy is a decentralised scheme, based on conventional droop control for active power sharing and grid frequency support. Droop control is also used within the DC microgrid for power sharing amongst generation and load. Scenarios are conducted to evaluate the effectiveness of the control strategy and verified by MATLAB/Simulink simulations
Diurnal Variation in Physiological and Immune Responses to Endurance Sport in Highly Trained Runners in a Hot and Humid Environment
Purpose. The purpose of this study was to investigate the physiological and immunological response of highly trained runners to an intense bout of exercise performed at two different times of day, in a hot, humid environment. Methods. Using a crossover randomized design, 13 highly trained runners (range VO 2 max 64â79 ml¡kg â1 min â1) performed a 10 km time trial run in hot (28 ° C) and humid conditions (70%), at 2 different times of day (09:00 hs and 18:00 hs). Venous blood samples were taken to determine WBCs (white blood cells), IL-6 (interleukin-6), CC16 (club cell protein 16), and HSP70 (heat shock protein-70) concentrations. Upper respiratory tract inflammation was additionally assessed using a nasal lavage procedure. Results. A significant diurnal difference (p < 0 05) was found for core body temperature, total WBC, and neutrophil and lymphocyte concentrations with higher values at 18:00 hs. A phase response in IL-6, HSP70, WBC, neutrophil, lymphocyte, and CC16 was noted, being more pronounced at 18:00 hs, whilst core body temperature and HR phase responses were more pronounced at 09:00 hs. Conclusion. In hot and humid conditions, athletes may wish to consider, when possible, racing and particularly training in the morning where the least homeostatic perturbation occurs
Diurnal physiological and immunological responses to a 10-km run in highly trained athletes in an environmentally controlled condition of 6 °C
PurposeThe Clara cell protein CC16, secreted from Clara cells in the lung, is discussed as a potential biomarker for toxic effects on the airways. An increased concentration of CC16 in serum may be caused by increased permeability of the lungs. To investigate the changes in P-CC16 in response to an intense exercise bout performed at different times of day (9 am and 4 pm) of highly trained individuals.MethodUsing a crossover randomized design, 8 runners (mean VO2max 71 ml kgâ1 minâ1, SD 6) performed a 10-km time trial run, at 9 am and 4 pm, in an environmental chamber set at 6 °C. Lung function tests and blood sampling occurred at baseline, immediately post and 1 h post time trial.ResultDiurnal differences (P < 0.05) were found for blood neutrophil and lymphocyte counts; with higher values at 4 pm. P-CC16 was higher at the pre- and post-trial time point at 9 am compared to 4 pm. Lung function was not different between or within trials.ConclusionMorning trial in cold condition caused more physiological strain compared to the same trial in the evening. However, this extra stress caused by zeitgebers could be a useful strategy for athletes, coaches, and general population to improve their running performance and protect their health in cold conditions in the long-term plan
Validating decentralised frequency control regimes : a distributed hardware in the loop approach
Ex Vivo treatment of coronary artery endothelial cells with serum post-exercise training offers limited protection against in vitro exposure to FEC-T chemotherapy
Background: Chemotherapy treatment for breast cancer associates with well-documented cardiovascular detriments. Exercise has shown promise as a potentially protective intervention against cardiac toxicity. However, there is a paucity of evidence for the benefits of exercise on the vasculature.
Objectives: This study aimed to determine the effects of chemotherapy on the vascular endothelium; and if there are protective effects of serological alterations elicited by an exercise training intervention.
Methods and Results: 15 women participated in a 12-week home-based exercise intervention consisting of three high-intensity interval sessions per week. Human coronary artery endothelial cells (HCAEC) were exposed to physiological concentrations of 5-fluorouracil, epirubicin, cyclophosphamide (FEC) and docetaxel to determine a dose-response. Twenty-4 hours prior to FEC and docetaxel exposure, HCAECs were preconditioned with serum collected pre- and post-training. Annexin V binding and cleaved caspase-3 were assessed using flow cytometry and wound repair by scratch assays. Chemotherapy exposure increased HCAEC Annexin V binding, cleaved caspase-3 expression in a dose-dependent manner; and inhibited wound repair. Compared to pre-training serum, conditioning HCAECs with post-training serum, reduced Annexin V binding (42% vs. 30%, p = 0.01) when exposed to FEC. For docetaxel, there were no within-group differences (pre-vs post-exercise) for Annexin V binding or cleaved caspase-3 expression. There was a protective effect of post-training serum on wound repair for 5-flurouracil (p = 0.03) only.
Conclusion: FEC-T chemotherapy drugs cause significant damage and dysfunction of endothelial cells. Preconditioning with serum collected after an exercise training intervention, elicited some protection against the usual toxicity of FEC-T, when compared to control serum
Painting the Nation:Examining the Intersection Between Politics and the Visual Arts Market in Emerging Economies
Politics and art have throughout history, intersected in diverse and complex ways. Ideologies and political systems have used the arts to create a certain image and, depending on the form of government this has varied from clear-cut state propaganda, to patronage, to more indirect arms-length funding procedures. Therefore, artists working within the macro-level socio-political context cannot help but be influenced, inspired and sometimes restricted by these policies and political influences. This article examines the contemporary art markets of two emerging, Socialist economies to investigate the relationship between state pol-itics and the contemporary visual arts market. We argue that the respective governments and art worlds are trying to construct a brand narrative for their nations, but that these discourses are often at cross-purposes. In doing so, we illustrate that it is impos-sible to separate a consideration of the artwork from the macro-level context in which it is produced, distributed, and consumed
Influence of country and city images on studentsâ perception of host universities and their satisfaction with the assigned destination for their exchange programmes
ABSTRACT: This research focuses on the effect that country image, city image and university image has on studentsâ a priori satisfaction with the assigned destination for their international exchange programme (Bachelor and Master). In particular, this study establishes six hypotheses related to the causal relationships among the different typologies of image and their effects on studentsâ satisfaction with the assigned destination to study at least one semester in a host university. In order to contrast these hypotheses, a quantitative research was carried out in the Spanish city of Santander (Spain), by obtaining a sample of 245 international students who participated in an exchange programme at the University of Cantabria. The research findings are: (1) studentsâ satisfaction with the assigned destination is positively influenced by the university image; (2) the university image is positively influenced by the city image; and (3) the city image is positively influenced by the country image
Living Near to Attractive Nature? A Well-Being Indicator for Ranking Dutch, Danish, and German Functional Urban Areas
- âŚ