4,116 research outputs found
Computer modeling of rocket engine ignition transients Final report
Computer modeling of rocket engine ignition transient
Non-Geometric Magnetic Flux and Crossed Modules
It is shown that the BRST operator of twisted N=4 Yang-Mills theory in four
dimensions is locally the same as the BRST operator of a fully decomposed
non-Abelian gerbe. Using locally defined Yang-Mills theories we describe
non-perturbative backgrounds that carry a novel magnetic flux. Given by
elements of the crossed module G x Aut G, these non-geometric fluxes can be
classified in terms of the cohomology class of the underlying non-Abelian
gerbe, and generalise the centre ZG valued magnetic flux found by 't Hooft.
These results shed light also on the description of non-local dynamics of the
chiral five-brane in terms of non-Abelian gerbes.Comment: 26 pages, LaTeX; v2: expanded, typos corrected; v3: typos corrected,
version to apper in Nucl. Phys.
Acute hypocalcemia and metabolic alkalosis in children on cation-exchange resin therapy
Background. Sodium polystyrene sulfonate (SPS) is a chelating agent used for the treatment of hyperkalemia. SPS has a wide range of exchange capacity requiring close monitoring of serum electrolytes. We observed two patients who developed acute hypocalcemia and increased metabolic alkalosis after initiating SPS therapy. We report these cases to draw attention to the potential risk of this medication in pediatric patients. Case Diagnosis/Treatment. Two children with chronic kidney disease on dialysis were started on SPS for hyperkalemia. Within a week after initiation of the medication, both patients developed hypocalcemia on routine labs without overt clinical manifestations. The hypocalcemia was rapidly corrected with oral supplementation and discontinuation of SPS. Conclusions. Severe hypocalcemia can develop after SPS therapy. The metabolic alkalosis in these patients associated with the hypocalcemia put them at increased risk for complications. Hence, careful attention must be paid to the state of calcium metabolism in all patients receiving SPS. Often calcium supplementation is required to maintain normal calcium levels
Effects of Volcanic Emissions on Clouds During Kilauea Degassing Events
Aerosols influence Earths radiative balance directly by scattering and absorbing solar radiation, and indirectly by modifying cloud properties. Current scientific consensus indicates that these effects may offset as much as 50% of the warming due to greenhouse gas emissions. Over the last two decades dramatic volcanic events in Hawaii have produced localized aerosol emissions in otherwise clean environments. These are natural experiments" where the aerosol effects on clouds and climate can be partitioned from other effects like meteorology and industrial emissions. Therefore, these events provide a unique opportunity to learn about possible effects of aerosol pollution on climate through cloud modification. In this work we use the version 5 of the NASA Goddard Earth Observing System (GEOS-5) and satellite retrievals to analyze and evaluate the strength of the aerosol indirect effect on liquid and ice clouds during the 2008 and 2018 Kilauea degassing events using different emissions scenarios (0, 1, and 5 actual emissions). Our results suggested that the 2018 event was stronger and more regionally significant with respect to cloud formation process for both liquid and ice clouds, while the 2008 affected local liquid clouds only. GEOS-5 predictions reproduced spatial patterns for all parameters, however better precision could be gained by using more accurate plume parameters for height and ash concentration
The role of protein hydrolysates for exercise-induced skeletal muscle recovery and adaptation:a current perspective
The protein supplement industry is expanding rapidly and estimated to have a multi-billion market worth. Recent research has centred on understanding how the manufacturing processes of protein supplements may impact muscle recovery and remodeling. The hydrolysed forms of protein undergo a further heating extraction process during production which may contribute to amino acids (AA) appearing in circulation at a slightly quicker rate, or greater amplitude, than the intact form. Whilst the relative significance of the rate of aminoacidemia to muscle protein synthesis is debated, it has been suggested that protein hydrolysates, potentially through the more rapid delivery and higher proportion of di-, tri- and smaller oligo-peptides into circulation, are superior to intact non-hydrolysed proteins and free AAs in promoting skeletal muscle protein remodeling and recovery. However, despite these claims, there is currently insufficient evidence to support superior muscle anabolic properties compared with intact non-hydrolysed proteins and/or free AA controls. Further research is warranted with appropriate protein controls, particularly in populations consuming insufficient amounts of protein, to support and/or refute an important muscle anabolic role of protein hydrolysates. The primary purpose of this review is to provide the reader with a current perspective on the potential anabolic effects of protein hydrolysates in individuals wishing to optimise recovery from, and maximise adaptation to, exercise training
Transients influencing rocket engine ignition and popping Interim report
Engine design and operating parameters studied for effects on rocket engine ignition and poppin
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Back to the future? A theoretically inspired musing on the concept of Product Stewardship and its implications for Corporate and Social Responsibility
yesThe concept of corporate and social responsibility (CSR) has gained increasing momentum and importance in business operations today and companies have globally responded to this philosophy. To what end though? Product Stewardship (PS) and the corporate, social and environmental responsibilities associated within this term are a key part of a business’s CSR agenda. In the extant literature, it is a challenge to clearly identify the boundaries of responsibility for PS - who sets these boundaries for governance and what are the actions taken under the guise of PS. This paper aims to start the process of demystification in responding to the title of this work, stimulate further musings and outline a future research agenda
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Where are you? A preliminary examination of the track and trace mechanisms in place to facilitate effective closed-loop medical equipment retrieval in the National Health Service (NHS) (UK)
yesThe National Health Service (UK) is wholly accountable and heavily scrutinised for its strategy, activity, performance and spending (Appleby, 2016; NHS Confederation, 2016; Parliament UK, 2010), and much research has been undertaken as to its effectiveness at managing its operations and its competency in doing so (Gov.Uk, 2016; National Audit Office, 1999)). The impact of not performing adequately combined with threats such as funding cuts (King’s Fund, 2016), government intervention and private sector competition; has led to uncertainty and disillusion with the sustainability of the service (Hunter, 2016). Based on current economic concerns, this paper chooses to focus on the area of Medical Equipment Loans Services where products are released to patients to aid therapeutic rehabilitation and physical mobility. The aim of this study is to examine the process of product retrieval in a multi-case study analysis and consider how value-added technologies can be used to improve retrieval success rates
Carbon dioxide kinetics and capnography during critical care
Greater understanding of the pathophysiology of carbon dioxide kinetics during steady and nonsteady state should improve, we believe, clinical care during intensive care treatment. Capnography and the measurement of end-tidal partial pressure of carbon dioxide (PETCO(2)) will gradually be augmented by relatively new measurement methodology, including the volume of carbon dioxide exhaled per breath (VCO(2,br)) and average alveolar expired PCO(2) (PAĚ…EĚ…CO(2)). Future directions include the study of oxygen kinetics
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