4,009 research outputs found
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The race to solve the sustainable transport problem via carbon-neutral synthetic fuels and battery electric vehicles
Carbon-neutral synthetic fuels (CNSFs) could offer sustainable alternatives to petroleum distillates that currently dominate the transportation sector, and address the challenge of decarbonising the fuel mix. CNSFs can be divided into synthetic biofuels and 'electrofuels' produced from CO2 and water with electricity. We provide a framework for comparing CNSFs to battery electric vehicles (BEVs) as alternatives to reduce vehicle emissions. Currently, all three options are significantly more expensive than conventional vehicles using fossil fuels, and would require carbon prices in excess of 150/bbl to become competitive. BEVs are emerging as a competitive option for short distances, but their competitiveness quickly deteriorates at higher ranges where synthetic biofuels are a lower-cost option. For electrofuels to be viable, the challenge is not simply technological learning, but access to a low-cost ultra-low-carbon electric power system, or to low-carbon electric generators with high annual availability
Determination of the resistivity anisotropy of SrRuO by measuring the planar Hall effect
We have measured the planar Hall effect in epitaxial thin films of the
itinerant ferromagnet SrRuO3 patterned with their current paths at different
angles relative to the crystallographic axes. Based on the results, we have
determined that SrRuO3 exhibits small resistivity anisotropy in the entire
temperature range of our measurements (between 2 to 300 K); namely, both above
and below its Curie temperature (~150 K). It means that in addition to
anisotropy related to magnetism, the resistivity anisotropy of SrRuO3 has an
intrinsic, nonmagnetic source. We have found that the two sources of anisotropy
have competing effects
Quaternion algebras with the same subfields
G. Prasad and A. Rapinchuk asked if two quaternion division F -algebras that
have the same subfields are necessarily isomorphic. The answer is known to be
"no" for some very large fields. We prove that the answer is "yes" if F is an
extension of a global field K so that F /K is unirational and has zero
unramified Brauer group. We also prove a similar result for Pfister forms and
give an application to tractable fields
Plasma Cortisol in Men – Relationship With Atherosclerosis of Retinal Arteries
The production of cortisol increases in acute stress but the effects of chronic stress on
plasma cortisol are still controversial. Stress on the other hand plays a role in coronary
artery disease (CAD) and carotid atherosclerosis. Since there is no data about plasma
cortisol and atherosclerosis of the retinal arteries, the purpose of this study was to explore
the relationship between plasma cortisol in 101 adult males with the degree of
their retinal vessels atherosclerosis. The results were compared with those in 47
matched apparently healthy men with no retinal vessels changes. The atherosclerotic
changes of retinal vessels were determined by direct ophthalmoscopy and graded (1–4)
according to Scheie. Morning plasma cortisol levels were determined by radioimmunoassay
using commercial kits. The results were compared by using chi-square test. No association
between morning plasma cortisol concentrations and retinal vessels atherosclerosis
could be found. The results of this study do not support a role for physiological
levels of plasma cortisol in the development of atherosclerosis, at least of the retinal arteries,
in men
The overlapping burden of the three leading causes of disability and death in sub-Saharan African children
Despite substantial declines since 2000, lower respiratory infections (LRIs), diarrhoeal diseases, and malaria remain among the leading causes of nonfatal and fatal disease burden for children under 5 years of age (under 5), primarily in sub-Saharan Africa (SSA). The spatial burden of each of these diseases has been estimated subnationally across SSA, yet no prior analyses have examined the pattern of their combined burden. Here we synthesise subnational estimates of the burden of LRIs, diarrhoea, and malaria in children under-5 from 2000 to 2017 for 43 sub-Saharan countries. Some units faced a relatively equal burden from each of the three diseases, while others had one or two dominant sources of unit-level burden, with no consistent pattern geographically across the entire subcontinent. Using a subnational counterfactual analysis, we show that nearly 300 million DALYs could have been averted since 2000 by raising all units to their national average. Our findings are directly relevant for decision-makers in determining which and targeting where the most appropriate interventions are for increasing child survival
Intellectual Property in Medical Imaging and Informatics: The Independent Inventor’s Perspective
While innovation and new product development is traditionally thought of as the exclusive domain of industry and academia, a large number of innovations in medicine and information technology have come from independent inventors, which account for almost 30% of new patents issued in the U.S. today. A large number of economic, political, and legal challenges exist within the current marketplace that serves as relative impediments to independent invention. This article explores the existing challenges facing the independent inventor and offers a number of recommendations and resources to facilitate independent inventors in their quest for innovation and entrepreneurship. The concept of “outsourcing innovation” is discussed as an alternative to the existing model of industry sponsored research and development (R&D), with the goal of combining the unique attributes and strengths of independent inventors and industry sponsors
Refinement of primary Si in hypereutectic Al-Si alloys by intensive melt shearing
Hypereutectic Al-Si based alloys are gaining popularity for applications where a combination of light weight and high wear resistance is required. The high wear resistance arising from the hard primary Si particles comes at the price of extremely poor machine tool life. To minimize machining problems while exploiting outstanding wear resistance, the primary Si particles must be controlled to a uniform small size and uniform spatial distribution. The current industrial means of refining primary Si chemically by the addition of phosphorous suffers from a number of problems. In the present paper an alternative, physical means of refining primary Si by intensive shearing of the melt prior to casting is investigated. Al-15wt%Si alloy has been solidified under varying casting conditions (cooling rate) and the resulting microstructures have been studied using microscopy and quantitative image analysis. Primary Si particles were finer, more compact in shape and more numerous with increasing cooling rate. Intensive melt shearing led to greater refinement and more enhanced nucleation of primary Si than was achieved by adding phosphorous. The mechanism of enhanced nucleation is discussed.EPSRC (grant EP/H026177/1)
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2010 EPRG Public Opinion Survey: Policy Preferences and Energy Saving Measures
This paper presents results of the 2010 Electricity Policy Research Group (EPRG) public opinion survey. The survey examines the energy policy preferences and attitudes of the British public, the potential for consumer engagement and consumer acceptance of various energy demand response activities. Wherever possible, comparisons were made to EPRG public opinion surveys from 2006 and 2008. Since the global financial crisis of 2008, energy and environmental concerns have decreased in priority, and respondents are more sceptical about government interventions in electricity markets. The share of individuals reporting that they are experiencing serious hardship due to energy prices has gone down from the 2008 level. While roughly half of the respondents would agree to have detailed metered consumption information recorded by their energy providers, they are even more wary about making data available to other entities. Local ownership is a potential motivating factor for public support for local small-scale energy plants. Energy efficiency measures had higher uptake than in previous years, but the widespread measures are typically cheaper and easiest to implement. There is scope for shifting discretionary electricity load to off-peak hours through both Time-of-Use tariffs and smart appliances that require limited user intervention.Time-of-use tariff
Financial stability evaluation of banks of the Russian Federation
In this paper we propose the model for evaluating financial stability of the Russian Federation banks by using discriminatory analysis. The statistical significance of the model was established. Critical value of the resulting was measured. The result of this research can be used in the area of banking
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