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Review of Flywheel based Internal Combustion Engine Hybrid Vehicles
Hybrid vehicles of different configurations and utilizing different energy storage systems have existed in development for many decades and more recently in limited production. They can be grouped as parallel, series or complex hybrids. Another classification is micro, mild and full hybrids which makes the distinction on the basis of functionality. The common energy storage systems in hybrid vehicles are batteries, supercapacitors and high speed flywheels. This paper aims to review a specific type of hybrid vehicle which involves the internal combustion engine (ICE) as the prime mover and the high speed flywheel as an energy storage device. Such hybrids are now attracting considerable interest given their potential for low cost. It is hence timely to produce a review of research and development in this subject. The flywheel is coupled to the drive line with a continuous variable transmission (CVT). The CVT can be of various types such as electrical, hydraulic or mechanical but usually in this case it is a non-electrical one. Different configurations are possible and the paper provides a timeline of the development of such powertrains with various examples. These types of hybrid vehicles have existed as prototypes for many decades and the authors believe that their development has reached levels where they can be considered serious contenders for production vehicles
The effects of social service contact on teenagers in England
Objective: This study investigated outcomes of social service contact during teenage years.
Method: Secondary analysis was conducted of the Longitudinal Survey of Young People in England (N = 15,770), using data on reported contact with social services resulting from teenagers’ behavior. Outcomes considered were educational achievement and aspiration, mental health, and locus of control. Inverse-probability-weighted regression adjustment was used to estimate the effect of social service contact.
Results: There was no significant difference between those who received social service contact and those who did not for mental health outcome or aspiration to apply to university. Those with contact had lower odds of achieving good exam results or of being confident in university acceptance if sought. Results for locus of control were mixed.
Conclusions: Attention is needed to the role of social services in supporting the education of young people in difficulty. Further research is needed on the outcomes of social services contact
Evidence for the formation of comet 67P/Churyumov-Gerasimenko through gravitational collapse of a bound clump of pebbles
The processes that led to the formation of the planetary bodies in the Solar System are still not fully understood. Using the results obtained with the comprehensive suite of instruments on-board ESA’s Rosetta mission, we present evidence that comet 67P/Churyumov-Gerasimenko likely formed through the gentle gravitational collapse of a bound clump of mm-sized dust aggregates (“pebbles”), intermixed with microscopic ice particles. This formation scenario leads to a cometary make-up that is simultaneously compatible with the global porosity, homogeneity, tensile strength, thermal inertia, vertical temperature profiles, sizes and porosities of emitted dust, and the steep increase in water-vapour production rate with decreasing heliocentric distance, measured by the instruments on-board the Rosetta spacecraft and the Philae lander. Our findings suggest that the pebbles observed to be abundant in protoplanetary discs around young stars provide the building material for comets and other minor bodies
Validation of 3D neutronic-thermalhydraulic coupled codes RELAP5/PARCSv2.7 and TRACEv5.0P3/PARCSv3.0 against a PWR control rod drop transient
[EN] In nuclear safety field, neutronic and thermalhydraulic codes performance is an important issue. New capabilities implementation, as well as models and tools improvements are a significant part of the community effort in looking for better Nuclear Power Plants (NPP) designs. A procedure to analyze the PWR response to local deviations on neutronic or thermalhydraulic parameters is being developed. This procedure includes the simulation of Incore and Excore neutron flux detectors signals. A control rod drop real plant transient is used to validate the used codes and their new capabilities. Cross-section data are obtained by means of the SIMTAB methodology. Detailed thermalhydraulic models were developed: RELAP5 and TRACE models simulate three different azimuthal zones. Besides, TRACE model is performed with a fully 3D core, thus, the cross-flow can be obtained. A cartesian vessel represents the fuel assemblies and a cylindrical vessel the bypass and downcomer. Simulated detectors signals are obtained and compared with the real data collected during a control rod drop trial at a PWR NPP and also with data obtained with SIMULATE-3K code.The authors would like to acknowledge the economic support provided by Centrales Nucleares Almaraz-Trillo (CNAT) and IBERDROLA Ingeniería y Construcción (Iberinco) for the realization of this work, and express their great appreciation to Arturo López, Juan Antonio Bermejo and Alberto Ortego for their valuable collaboration and their willingness to develop this work. This work has also been supported by the Spanish Ministerio de Economía y Competitividad, through the projects NUC-MULTPHYS (ENE2012-34585) and VALIUN-3D (ENE2011-22823), and the Generalitat Valenciana (GVA), through the project PROMETEO II/2014/008.Garcia-Fenoll, M.; Mesado Melia, C.; Barrachina, T.; Miró Herrero, R.; Verdú Martín, GJ.; Bermejo, JA.; López, A.... (2017). Validation of 3D neutronic-thermalhydraulic coupled codes RELAP5/PARCSv2.7 and TRACEv5.0P3/PARCSv3.0 against a PWR control rod drop transient. Journal of Nuclear Science and Technology. 54(8):908-919. https://doi.org/10.1080/00223131.2017.1329035S90891954
A systematic review of the safety information contained within the Summaries of Product Characteristics of medications licensed in the United Kingdom for Attention Deficit Hyperactivity Disorder. how does the safety prescribing advice compare with national guidance?
<p>Abstract</p> <p>Background</p> <p>The safety of paediatric medications is paramount and contraindications provide clear pragmatic advice. Further advice may be accessed through Summaries of Product Characteristics (SPCs) and relevant national guidelines. The SPC can be considered the ultimate independent guideline and is regularly updated. In 2008, the authors undertook a systematic review of the SPC contraindications of medications licensed in the United Kingdom (UK) for the treatment of Attention Deficit Hyperactivity Disorder (ADHD). At that time, there were fewer contraindications reported in the SPC for atomoxetine than methylphenidate and the specific contraindications varied considerably amongst methylphenidate formulations. In 2009, the European Medicines Agency (EMA) mandated harmonisation of methylphenidate SPCs. Between September and November 2011, there were three changes to the atomoxetine SPC that resulted in revised prescribing information. In addition, Clinical Guidance has also been produced by the National Institute for Health and Clinical Excellence (NICE) (2008), the Scottish Intercollegiate Guidelines Network (SIGN) (2009) and the British National Formulary for Children (BNFC).</p> <p>Methods</p> <p>An updated systematic review of the Contraindications sections of the SPCs of all medications currently licensed for treatment of ADHD in the UK was undertaken and independent statements regarding contraindications and relevant warnings and precautions were then compared with UK national guidance with the aim of assessing any disparity and potential areas of confusion for prescribers.</p> <p>Results</p> <p>As of November 2011, there were seven medications available in the UK for the treatment of ADHD. There are 15 contraindications for most formulations of methylphenidate, 14 for dexamfetamine and 5 for atomoxetine. Significant differences exist between the SPCs and national guidance part due to the ongoing reactive process of amending the former as new information becomes known. In addition, recommendations are made outside UK SPC licensed indications and a significant contraindication for methylphenidate (suicidal behaviours) is missing from both the NICE and SIGN guidelines. Particular disparity exists relating to monitoring for suicidal and psychiatric side effects. The BNFC has not yet been updated in line with the European Union (EU) Directive on methylphenidate; it does not include any contraindications for atomoxetine but describes contraindications for methylphenidate that are no longer in the SPC.</p> <p>Conclusion</p> <p>Clinicians seeking prescribing advice from critical independent sources of data, such as SPCs and national guidelines, may be confused by the disparity that exists. There are major differences between guidelines and SPCs and neither should be referred to in isolation. The SPC represents the most relevant source of safety data to aid prescribing of medications for ADHD as they present the most current safety data in line with increased exposure. National guidelines may need more regular updates.</p
Quantum Metrology Triangle Experiments: A Status Review
Quantum Metrology Triangle experiments combine three quantum electrical
effects (the Josephson effect, the quantum Hall effect and the single-electron
transport effect) used in metrology. These experiments allow important
fundamental consistency tests on the validity of commonly assumed relations
between fundamental constants of nature and the quantum electrical effects.
This paper reviews the history, results and the present status and perspectives
of Quantum Metrology Triangle experiments. It also reflects on the possible
implications of results for the knowledge on fundamental constants and the
quantum electrical effects.Comment: 36 pages, 8 figure
Knowledge of causes, clinical features and diagnosis of common zoonoses among medical practitioners in Tanzania
Many factors have been mentioned as contributing to under-diagnosis and under-reporting of zoonotic diseases particularly in the sub-Sahara African region. These include poor disease surveillance coverage, poor diagnostic capacity, the geographical distribution of those most affected and lack of clear strategies to address the plight of zoonotic diseases. The current study investigates the knowledge of medical practitioners of zoonotic diseases as a potential contributing factor to their under-diagnosis and hence under-reporting. The study was designed as a cross-sectional survey. Semi-structured open-ended questionnaire was administered to medical practitioners to establish the knowledge of anthrax, rabies, brucellosis, trypanosomiasis, echinococcosis and bovine tuberculosis in selected health facilities within urban and rural settings in Tanzania between April and May 2005. Frequency data were analyzed using likelihood ratio chi-square in Minitab version 14 to compare practitioners' knowledge of transmission, clinical features and diagnosis of the zoonoses in the two settings. For each analysis, likelihood ratio chi-square p-value of less than 0.05 was considered to be significant. Fisher's exact test was used where expected results were less than five. Medical practitioners in rural health facilities had poor knowledge of transmission of sleeping sickness and clinical features of anthrax and rabies in humans compared to their urban counterparts. In both areas the practitioners had poor knowledge of how echinococcosis is transmitted to humans, clinical features of echinococcosis in humans, and diagnosis of bovine tuberculosis in humans. Knowledge of medical practitioners of zoonotic diseases could be a contributing factor to their under-diagnosis and under-reporting in Tanzania. Refresher courses on zoonotic diseases should be conducted particularly to practitioners in rural areas. More emphasis should be put on zoonotic diseases in teaching curricula of medical practitioners' training institutions in Tanzania to improve the diagnosis, reporting and control of zoonotic diseases. Veterinary and medical collaboration should be strengthened to enable more effective control of zoonotic diseases in Tanzania
Too Big to Fail — U.S. Banks’ Regulatory Alchemy: Converting an Obscure Agency Footnote into an “At Will” Nullification of Dodd-Frank’s Regulation of the Multi-Trillion Dollar Financial Swaps Market
The multi-trillion-dollar market for, what was at that time wholly unregulated, over-the-counter derivatives (“swaps”) is widely viewed as a principal cause of the 2008 worldwide financial meltdown. The Dodd-Frank Act, signed into law on July 21, 2010, was expressly considered by Congress to be a remedy for this troublesome deregulatory problem. The legislation required the swaps market to comply with a host of business conduct and anti-competitive protections, including that the swaps market be fully transparent to U.S. financial regulators, collateralized, and capitalized. The statute also expressly provides that it would cover foreign subsidiaries of big U.S. financial institutions if their swaps trading could adversely impact the U.S. economy or represent the use of extraterritorial trades as an attempt to “evade” Dodd-Frank. In July 2013, the CFTC promulgated an 80-page, triple-columned, and single-spaced “guidance” implementing Dodd-Frank’s extraterritorial reach, i.e., that manner in which Dodd-Frank would apply to swaps transactions executed outside the United States. The key point of that guidance was that swaps trading within the “guaranteed” foreign subsidiaries of U.S. bank holding company swaps dealers were subject to all of Dodd-Frank’s swaps regulations wherever in the world those subsidiaries’ swaps were executed. At that time, the standardized industry swaps agreement contemplated that, inter alia, U.S. bank holding company swaps dealers’ foreign subsidiaries would be “guaranteed” by their corporate parent, as was true since 1992. In August 2013, without notifying the CFTC, the principal U.S. bank holding company swaps dealer trade association privately circulated to its members standard contractual language that would, for the first time, “deguarantee” their foreign subsidiaries. By relying only on the obscure footnote 563 of the CFTC guidance’s 662 footnotes, the trade association assured its swaps dealer members that the newly deguaranteed foreign subsidiaries could (if they so chose) no longer be subject to Dodd-Frank. As a result, it has been reported (and it also has been understood by many experts within the swaps industry) that a substantial portion of the U.S. swaps market has shifted from the large U.S. bank holding companies swaps dealers and their U.S. affiliates to their newly deguaranteed “foreign” subsidiaries, with the attendant claim by these huge big U.S. bank swaps dealers that Dodd-Frank swaps regulation would not apply to these transactions. The CFTC also soon discovered that these huge U.S. bank holding company swaps dealers were “arranging, negotiating, and executing” (“ANE”) these swaps in the United States with U.S. bank personnel and, only after execution in the U.S., were these swaps formally “assigned” to the U.S. banks’ newly “deguaranteed” foreign subsidiaries with the accompanying claim that these swaps, even though executed in the U.S., were not covered by Dodd-Frank. In October 2016, the CFTC proposed a rule that would have closed the “deguarantee” and “ANE” loopholes completely. However, because it usually takes at least a year to finalize a “proposed” rule, this proposed rule closing the loopholes in question was not finalized prior to the inauguration of President Trump. All indications are that it will never be finalized during a Trump Administration. Thus, in the shadow of the recent tenth anniversary of the Lehman failure, there is an understanding among many market regulators and swaps trading experts that large portions of the swaps market have moved from U.S. bank holding company swaps dealers and their U.S. affiliates to their newly deguaranteed foreign affiliates where Dodd- Frank swaps regulation is not being followed. However, what has not moved abroad is the very real obligation of the lender of last resort to rescue these U.S. swaps dealer bank holding companies if they fail because of poorly regulated swaps in their deguaranteed foreign subsidiaries, i.e., the U.S. taxpayer. While relief is unlikely to be forthcoming from the Trump Administration or the Republican-controlled Senate, some other means will have to be found to avert another multi-trillion-dollar bank bailout and/or a financial calamity caused by poorly regulated swaps on the books of big U.S. banks. This paper notes that the relevant statutory framework affords state attorneys general and state financial regulators the right to bring so-called “parens patriae” actions in federal district court to enforce, inter alia, Dodd- Frank on behalf of a state’s citizens. That kind of litigation to enforce the statute’s extraterritorial provisions is now badly needed
Optimization of a Morphing Wing Based on Coupled Aerodynamic and Structural Constraints
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77091/1/AIAA-39016-101.pd
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