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Rio, Tokyo Paralympic Games and beyond: How to Prepare Athletes with Motor Disabilities for Peaking

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889451715 Year: Pages: 87 DOI: 10.3389/978-2-88945-171-5 Language: English
Publisher: Frontiers Media SA
Subject: Physiology --- Science (General)
Added to DOAB on : 2017-08-28 14:01:09
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In 1960, the 9th Annual International Stoke Mandeville Games were supported, for the first time, by the Italian Olympic Committee. Taking place six days after the Closing Ceremony of the XVII Olympic Games, the paralympic games for disabled athletes were born. From Roma in 1960 to London in 2012, the Paralympic Games grew in terms of athletes’ number from 400 to 4,237, and now brings together more than 164 nations (Perret, 2015). The word “Paralympic” derives from the Greek preposition “para” (beside or alongside) and the word “Olympic”. Paralympics want to be the parallel Games to the Olympics and illustrate how the two movements exist side-by-side (Paralympics – History of the Movement, 2016). Now taking place after the Olympics Games, the Paralympic Games are the pinnacle of the career of athletes with physical impairments and have become the second largest sport event in the world (Perret, 2015; Paralympics – History of the Movement, 2016; Gold and Gold, 2011). The first statement of the vision of the International Paralympic Committee (IPC), i.e. “to create the conditions for athlete empowerment through self-determination” (Paralympics – History of the Movement, 2016; International Paralympic Committee, 2016), shows the importance of the place of the athlete with an impairment at the heart of the Paralympic Movement. The ultimate aim of the IPC is « to enable Paralympic athletes to achieve sporting excellence and inspire and excite the world. » (International Paralympic Committee, 2016). The performance level of athletes with an impairment improved to a point that, in the present days, sport news and world sport movements focus on the potential advantage of artificial limbs among athletes with amputations and their integration in able-bodied competitions (Burkett, 2010). However, they do not represent the totality of athletes with an impairment at the Paralympic Games. Athletes with other physical impairments (visual deficit, spinal cord injury, cerebral palsy or else) are eligible to compete. These impairments induce typical functional and physiological (e.g., cardiovascular, thermoregulatory) responses to exercise. For example, spinal cord injury (athletes with tetraplegia or paraplegia) causes thermoregulatory impairment (Goosey-Tolfrey et al., 2008) and individuals with cerebral palsy have also demonstrated higher thermal and metabolic strain than matched controls during treadmill walking in the heat (Maltais et al., 2004). Thus, hyperthermia among these athletes with an impairment alters their performance compared to their Olympic counterparts (Bhambhani, 2002). Mechanical performance analysis, the description of physiological responses according to the functional impairment or else the response to training and the relationship between laboratory and field testing responses are different parts of a package introduced here to address the aim of the IPC: to enable Paralympic athletes to achieve sporting excellence (Paralympics – History of the Movement, 2016; International Paralympic Committee, 2016).

Keywords

Paralympics --- performance --- Disability --- Athletes --- heat

Heat Transfer Processes in Oscillatory Flow Conditions

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ISBN: 9783038427094 9783038427100 Year: Pages: VI, 172 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Heat
Added to DOAB on : 2018-04-27 16:01:54
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Heat exchange processes in steady flows have been studied extensively over the last two hundred years, and are now a part of undergraduate syllabi in most engineering courses. However, heat transfer processes in oscillatory flow conditions are still not very well understood. Their importance is well recognized in applications including Stirling machines, thermoacoustic engines, and refrigerators or pulsed-tube coolers in cryogenics. Additionally, the enhancement of heat transfer by using oscillatory, and, in some cases, pulsating flows is important in many areas of mechanical and chemical engineering for the intensification of heat transfer processes and possible miniaturization of heat exchangers of the future.This Special Issue was intended as a dissemination platform for researchers working in the field to have an opportunity to consolidate recent advances in this important research area. All types of research approaches were invited, including experimental, theoretical, computational fluid dynamics (CFD), and their combinations, while the approaches could be either of a fundamental or applied nature. The guest editor and the editorial team of Applied Sciences hope that the readership will find the selection of ten articles presented here a useful contribution to the emerging field of heat transfer processes in oscillatory flow conditions.

HSPs - Ambiguous Mediators of Immunity

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889451524 Year: Pages: 92 DOI: 10.3389/978-2-88945-152-4 Language: English
Publisher: Frontiers Media SA
Subject: Allergy and Immunology --- Medicine (General)
Added to DOAB on : 2017-08-28 14:01:09
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Heat shock proteins (HSPs) were discovered as polypeptides induced by stress that can be found in all kingdoms of cellular organisms. Their functions were, a first enigmatic and these proteins were thus classified by molecular weight, as in—Hsp27, Hsp70, Hsp90, Hsp110. More recently, each of these size-classified molecules has attributed a role in protein folding, and they thus came to be known, as a class, as molecular chaperones. However, the they possess properties beyond chaperoning. Indeed, their discovery in the extracellular spaces suggested roles in regulation of the immune responses.

The immunology of cellular stress proteins

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889193257 Year: Pages: 89 DOI: 10.3389/978-2-88919-325-7 Language: English
Publisher: Frontiers Media SA
Subject: Allergy and Immunology --- Medicine (General)
Added to DOAB on : 2016-03-10 08:14:32
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Stress proteins or heat-shock proteins (HSP) are evolutionary conserved proteins present in every prokaryotic and eukaryotic cell. Their main function is to protect cells and proteins from damage under stressful circumstances. The latter circumstances do include the cell and protein damaging effects of inflammation. The discovery of mycobacterial HSP60 being a critical antigen in the model of adjuvant arthritis, has led to studies that showed the immuno-dominance of microbial HSP60 and the potential of the microbial HSP induced repertoire of antibodies and T cells to cross-recognize the self-HSP homologues of stressed cells. Since then, the research in the immunology of stress proteins started to comprise a widening spectrum of topics with potential medical relevance. Interestingly, since stress proteins have their activities in both innate and adaptive immunity, they are key elements in the cross-roads between both arms of the immune system. Stress proteins or HSP can be considered as functional 'biomarkers' of inflammation. They are up-regulated locally during inflammation and interestingly, they seem to function as targets for anti-inflammatory regulatory T cells. In experimental models of autoimmunity, mainly arthritis, administration of HSP peptides have been shown to suppress disease. First clinical trials have shown the anti-inflammatory nature of T cell responses to Hsp. In type I diabetes and in rheumatoid arthritis, parenteral and oral administration of Hsp peptides were shown to induce a bias in pro-inflammatory T cells, switching them in the direction of regulatory cytokine production (IL4, IL5 and IL10). In addition a raised level of a marker of natural T regulatory cells, the transcription factor FoxP3, was noted in the RA trial. Other inflammatory diseases or diseases with inflammatory components which feature the immune imprint of the up-regulated Hsp are atherosclerosis, inflammatory bowel diseases, multiple sclerosis and atopic diseases such atopic dermatitis and allergic asthma.

The HSP70 Molecular Chaperone Machines

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889451258 Year: Pages: 69 DOI: 10.3389/978-2-88945-125-8 Language: English
Publisher: Frontiers Media SA
Subject: Science (General)
Added to DOAB on : 2017-07-06 13:27:36
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Members of the HSP70 family form a central hub of the molecular chaperone network, controlling protein homeostasis in prokaryotes and in the ATP-containing compartments of the eukaryotic cells. The heat-inducible form HSPA1A (HSP70), its constitutive cytosolic cognate HSPA8 (Hsc70), its endoplasmic reticulum form HSPA5 (BiP), and its mitochondrial form HSPA9 (Mortalin), as well as the more distantly related HSPHs (HSP110s), make up 1-2 % of the total mass of proteins in human cells. They use the energy of ATP-hydrolysis to prevent and forcefully revert the process of protein misfolding and aggregation during and following various stresses, presumably by working as unfoldases to lift aberrant conformers out of kinetic traps. As such, HSP70s, in cooperation with their J-domain co-chaperones and nucleotide exchange factors (NEFs) and co-disaggregases, form an efficient network of cellular defenses against the accumulation of cytotoxic misfolded protein conformers, which may cause degenerative diseases such as Parkinson's and Alzheimer's disease, diabetes, and aging in general. In addition to their function in repair of stress-induced damage, HSP70s fulfill many housekeeping functions, including assisting the de novo folding and maturation of proteins, driving the translocation of protein precursors across narrow membrane pores into organelles, and by controlling the oligomeric state of key regulator protein complexes involved in signal transduction and vesicular trafficking. For reasons not well understood, HSP70s are also found on the surface of some animal cells, in particular cancer cells where they may serve as specific targets for cancer immunotherapy. Here, we gathered seven mini reviews, each presenting a complementary aspect of HSP70’s structure and function in bacteria and eukaryotes, under physiological and stressful conditions. These articles highlight how, the various members of this conserved family of molecular chaperones, assisted by their various J-domain and NEF cochaperones and co-disaggregases, harness ATP hydrolysis to perform a great diversity of life-sustaining cellular functions using a similar molecular mechanism.

Molecular Chaperones and Neurodegeneration

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889453429 Year: Pages: 180 DOI: 10.3389/978-2-88945-342-9 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Neurology
Added to DOAB on : 2018-02-27 16:16:45
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Molecular chaperones or heat-shock proteins (HSPs) play essential roles in safeguarding structural stability and preventing misfolding and aggregation of proteins, and maintaining the proteome functionality in the cell. For over two decades until the present time, new functions have been discovered and several molecular mechanisms have been elucidated for many chaperones, while the field is being continuously challenged by new open questions. Probably as a consequence of the increasing research on the molecular bases of neurodegenerative diseases, and the realisation that many such disorders are linked to protein misfolding processes, unleashing the roles and mechanisms of chaperones in the context of neurodegeneration has become a prime scientific goal. This e-book contains a diversity of reviews, perspective and original research articles highlighting the importance and potential of this emerging subject.

Flow and Heat or Mass Transfer in the Chemical Process Industry

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ISBN: 9783038972389 9783038972396 Year: Pages: 214 DOI: 10.3390/books978-3-03897-239-6 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: General and Civil Engineering
Added to DOAB on : 2018-09-28 12:14:25
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ca. 200 words; this text will present the book in all promotional forms (e.g. flyers). Please describe the book in straightforward and consumer-friendly terms.[Flow through process equipment in a chemical or manufacturing plant (e.g., heat exchangers, reactors, catalyst regeneration units, separation units, pumps, pipes, smoke stacks, etc.) is usually coupled with heat and/or mass transfer. Rigorous investigation of this coupling of momentum, heat, and mass transfer is not only important for the practice of designing process equipment, but is also important for improving our overall theoretical understanding of transfer phenomena. While generalizations and empiricisms, like the concept of the heat transfer coefficient or the widely used Reynolds analogy in turbulence, or the use of empirical transfer equations for flow in separation towers and reactors packed with porous media, have served practical needs in prior decades, such empiricisms can now be revised or altogether replaced by bringing modern experimental and computational tools to bear in understanding the interplay between flow and transfer. The patterns of flow play a critical role in enhancing the transfer of heat and mass. Typical examples are the coherent flow structures in turbulent boundary layers, which are responsible for turbulent transfer and mixing in a heat exchanger and for dispersion from a smoke stack, and the flow patterns that are a function of the configuration of a porous medium and are responsible for transfer in a fixed bed reactor or a fluid bed regenerator unit. The goal of this Special Issue is to be a forum for recent developments in theory, state-of-the-art experiments and computations on the interactions between flow and transfer in single and multi-phase flow, and from small scales to large scales, which can be important for the design of equipment in a chemical processing plant.]

Geothermal Energy: Delivering on the Global Potential

ISBN: 9783038421337 9783038421344 Year: Pages: 430 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Added to DOAB on : 2016-05-20 14:48:30
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After decades of being largely the preserve of countries in volcanic regions, the use of geothermal energy—for both heat and power applications—is now expanding worldwide. This reflects its excellent low-carbon credentials and its ability to offer baseload and dispatchable output - rare amongst the mainstream renewables. Yet uptake of geothermal still lags behind that of solar and wind, principally because of (i) uncertainties over resource availability in poorly-explored reservoirs and (ii) the concentration of full-lifetime costs into early-stage capital expenditure (capex). Recent advances in reservoir characterization techniques are beginning to narrow the bounds of exploration uncertainty, both by improving estimates of reservoir geometry and properties, and by providing pre-drilling estimates of temperature at depth. Advances in drilling technologies and management have potential to significantly lower initial capex, while operating expenditure is being further reduced by more effective reservoir management — supported by robust mathematical models — and increasingly efficient energy conversion systems (flash, binary and combined-heat-and-power). Advances in characterization and modelling are also improving management of shallow low-enthalpy resources that can only be exploited using heat-pump technology. Taken together with increased public appreciation of the benefits of geothermal, the technology is finally ready to take its place as a mainstream renewable technology, This book draws together some of the latest developments in concepts and technology that are enabling the growing realisation of the global potential of geothermal energy in all its manifestations.After decades of being largely the preserve of countries in volcanic regions, the use of geothermal energy—for both heat and power applications—is now expanding worldwide. This reflects its excellent low-carbon credentials and its ability to offer baseload and dispatchable output - rare amongst the mainstream renewables. Yet uptake of geothermal still lags behind that of solar and wind, principally because of (i) uncertainties over resource availability in poorly-explored reservoirs and (ii) the concentration of full-lifetime costs into early-stage capital expenditure (capex). Recent advances in reservoir characterization techniques are beginning to narrow the bounds of exploration uncertainty, both by improving estimates of reservoir geometry and properties, and by providing pre-drilling estimates of temperature at depth. Advances in drilling technologies and management have potential to significantly lower initial capex, while operating expenditure is being further reduced by more effective reservoir management — supported by robust mathematical models — and increasingly efficient energy conversion systems (flash, binary and combined-heat-and-power). Advances in characterization and modelling are also improving management of shallow low-enthalpy resources that can only be exploited using heat-pump technology. Taken together with increased public appreciation of the benefits of geothermal, the technology is finally ready to take its place as a mainstream renewable technology.

Coding Properties in Invertebrate Sensory Systems

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889451067 Year: Pages: 227 DOI: 10.3389/978-2-88945-106-7 Language: English
Publisher: Frontiers Media SA
Subject: Physiology --- Science (General)
Added to DOAB on : 2017-07-06 13:27:36
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Animals rely on sensory input from their environment for survival and reproduction. Depending on the importance of a signal for a given species, accuracy of sensory coding might vary from pure detection up to precise coding of intensity, quality and temporal features of the signal. Highly sophisticated sense organs and related central nervous sensory pathways can be of utmost importance for animals in a complex environment and when using advanced communication systems. In sensory systems different anatomical and physiological features have evolved to optimally encode behaviourally relevant signals at the level of sense organs and central processing. The wide range of organizational complexity, in combination with their relatively simple and accessible nervous systems, makes invertebrates excellent models to study general sensory coding principles. The contributions to this e-book illustrate on one hand particular features of specific sensory systems, and on the other hand indicate not only common features of sensory coding across invertebrate phyla, but also similar processing principles of complex stimuli between different sensory modalities. The chapters show that the extraction of behaviourally relevant signals from all environmental stimuli, as well as the detection of low intensity signals and the analysis of temporal features can be similar across sensory modalities, including olfaction, vision, mechanoreception, and heat perception.

Abiotic Stresses in Agroecology: A Challenge for Whole Plant Physiology

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889452040 Year: Pages: 177 DOI: 10.3389/978-2-88945-204-0 Language: English
Publisher: Frontiers Media SA
Subject: Environmental Sciences --- Botany --- Science (General)
Added to DOAB on : 2017-10-13 14:57:01
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Understanding plant responses to abiotic stresses is central to our ability to predict the impact of global change and environmental pollution on the production of food, feed and forestry. Besides increasing carbon dioxide concentration and rising global temperature, increasingly frequent and severe climatic events (e.g. extended droughts, heat waves, flooding) are expected in the coming decades. Additionally, pollution (e.g. heavy metals, gaseous pollutants such as ozone or sulfur dioxide) is an important factor in many regions, decreasing plant productivity and product quality. This Research topic focuses on stress responses at the level of whole plants, addressing biomass-related processes (development of the root system, root respiration/fermentation, leaf expansion, stomatal regulation, photosynthetic capacity, leaf senescence, yield) and interactions between organs (transport via xylem and phloem, long-distance signaling and secondary metabolites). Comparisons between species and between varieties of the same species are helpful to evaluate the potential for species selection and genetic improvement. This research topic is focused on the following abiotic stresses and interactions between them:- Increased carbon dioxide concentration in ambient air is an important parameter influenced by global change and affects photosynthesis, stomatal regulation, plant growth and finally yield.- Elevated temperature: both the steady rise in average temperature and extreme events of shorter duration (heat waves) must be considered in the context of alterations in carbon balance through increased photorespiration, decreased Rubisco activation and carboxylation efficiency, damage to photosynthetic apparatus, as well as loss of water via transpiration and stomatal sensitivity. - Low temperatures (late frosts, prolonged cold phases, freezing temperature) can decrease overwintering survival rates, productivity of crop plants and species composition in meadows.- Water availability: More frequent, severe and extended drought periods have been predicted by climate change models. The timing and duration of a drought period is crucial to determining plant responses, particularly if the drought event coincides with an increase in temperature. Drought causes stomatal closure, decreasing the cooling potential of transpiration and potentially leading to thermal stress as leaf temperature rises. Waterlogging may become also more relevant during the next decades and is especially important for seedlings and young plants. It is not the presence of water itself that causes the stress, but the exclusion of oxygen from the soil which causes a decrease in respiration and an increase in fermentation rates followed by a period of potential oxidative stress as water recedes.- Salinity: high salt concentration in soil influences soil water potential, the water status of the plant and hence affects productivity. Salt tolerance will become an important trait driven by increased competition for land and the need to exploit marginal lands.

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