416 research outputs found
PBL Take to the Air: Airline Development
In this sample Problem Based Learning (PBL) unit, students are faced with the problem of a new airline being developed in the Chicago area. Students investigate the economic and community impact along with marketing and aircraft considerations. This sample unit is intended for educators learning to use PBL methods in their classroom
Approximate solutions to a model of two-component reactive flow
We consider a model of motion of binary mixture, based on the compressible Navier-Stokes system. The mass balances of chemically reacting species are described by the reaction-diffusion equations with generalized form of multicomponent difiusion ux. Under a special relation between the two density dependent viscosity coefficients and for singular cold pressure we construct the weak solutions passing through several levels of approximation
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Developing a quick guide on presenting data and uncertainty
This paper describes the rationale, development and testing of a quick guide leaflet on the presentation of data and uncertainty. While tools for capturing, analysing and presenting data become more advanced, the fundamentals of presenting data with adequate context and clarity remain unchanged. The leaflet, aimed at scientists generating and presenting data, was created as part of an interdisciplinary collaboration (meteorologists, information designers, psychologists) working within the PURE Network project RACER, funded by the UK Natural Environment Research Council. A copy of the leaflet is included in this article
The role of agri-environment schemes in conservation and environmental management.
Over half of the European landscape is under agricultural management and has been for millennia. Many species and ecosystems of conservation concern in Europe depend on agricultural management and are showing ongoing declines. Agri-environment schemes (AES) are designed partly to address this. They are a major source of nature conservation funding within the European Union (EU) and the highest conservation expenditure in Europe. We reviewed the structure of current AES across Europe. Since a 2003 review questioned the overall effectiveness of AES for biodiversity, there has been a plethora of case studies and meta-analyses examining their effectiveness. Most syntheses demonstrate general increases in farmland biodiversity in response to AES, with the size of the effect depending on the structure and management of the surrounding landscape. This is important in the light of successive EU enlargement and ongoing reforms of AES. We examined the change in effect size over time by merging the data sets of 3 recent meta-analyses and found that schemes implemented after revision of the EU's agri-environmental programs in 2007 were not more effective than schemes implemented before revision. Furthermore, schemes aimed at areas out of production (such as field margins and hedgerows) are more effective at enhancing species richness than those aimed at productive areas (such as arable crops or grasslands). Outstanding research questions include whether AES enhance ecosystem services, whether they are more effective in agriculturally marginal areas than in intensively farmed areas, whether they are more or less cost-effective for farmland biodiversity than protected areas, and how much their effectiveness is influenced by farmer training and advice? The general lesson from the European experience is that AES can be effective for conserving wildlife on farmland, but they are expensive and need to be carefully designed and targeted.This is the final published version. It first appeared from Wiley http://dx.doi.org/10.1111/cobi.1253
PRODUCTION OF MONOGLYCERIDES AND DIGLYCERIDES THROUGH LIPASE-CATALYZED GLYCEROLYSIS AND MOLECULAR DISTILLATION.
PRODUCTION OF MONOGLYCERIDES AND DIGLYCERIDES THROUGH LIPASE-CATALYZED GLYCEROLYSIS AND MOLECULAR DISTILLATION. Monoacilglycerides and diacilglycerides are produced through lipase-catalyzed glycerolysis of soybean oil using Candida antarctica B in a solvent-free system. The reaction was carried Out at a glycerol to triacylglycerol molar ratio of 8:1 with 2% of lipase. Acylglycerides, free fatty acids (FFA) and glycerol produced were separated employing the molecular distillation process. Starting from a product of enzymatic reaction 25.06% of triacylglycerols, 46.63% of diacylglycerides. 21.72% of monoacylglycerides, 5.38% of FFA and 1.21% of glycerol and after consecutively distillations. monoacylglycerides with 80% of purity was obtained and also oil with 54% of diacylglycerides to be used in human dietary.3261539154
The potential of a Mobility-as-a-Service platform in a depopulating area in the Netherlands: An exploration of small and big data
This chapter describes a case study examining the potential of a community-driven Mobility-as-a-Service (MaaS) platform in a rural and depopulating area in the Netherlands. The aim of the 5-year project is to examine if a MaaS platform can be an effective and efficient solution to improve accessibility and liveability of rural areas. The potential for a MaaS is examined by addressing the current mobility patterns and mobility and accessibility barriers. We use a mixed method approach using a combination of small data (primary data) and big data (secondary data)
Seeing ‘Where’ through the Ears: Effects of Learning-by-Doing and Long-Term Sensory Deprivation on Localization Based on Image-to-Sound Substitution
BACKGROUND: Sensory substitution devices for the blind translate inaccessible visual information into a format that intact sensory pathways can process. We here tested image-to-sound conversion-based localization of visual stimuli (LEDs and objects) in 13 blindfolded participants. METHODS AND FINDINGS: Subjects were assigned to different roles as a function of two variables: visual deprivation (blindfolded continuously (Bc) for 24 hours per day for 21 days; blindfolded for the tests only (Bt)) and system use (system not used (Sn); system used for tests only (St); system used continuously for 21 days (Sc)). The effect of learning-by-doing was assessed by comparing the performance of eight subjects (BtSt) who only used the mobile substitution device for the tests, to that of three subjects who, in addition, practiced with it for four hours daily in their normal life (BtSc and BcSc); two subjects who did not use the device at all (BtSn and BcSn) allowed assessment of its use in the tasks we employed. The impact of long-term sensory deprivation was investigated by blindfolding three of those participants throughout the three week-long experiment (BcSn, BcSn/c, and BcSc); the other ten subjects were only blindfolded during the tests (BtSn, BtSc, and the eight BtSt subjects). Expectedly, the two subjects who never used the substitution device, while fast in finding the targets, had chance accuracy, whereas subjects who used the device were markedly slower, but showed much better accuracy which improved significantly across our four testing sessions. The three subjects who freely used the device daily as well as during tests were faster and more accurate than those who used it during tests only; however, long-term blindfolding did not notably influence performance. CONCLUSIONS: Together, the results demonstrate that the device allowed blindfolded subjects to increasingly know where something was by listening, and indicate that practice in naturalistic conditions effectively improved "visual" localization performance
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The impact of European legislative and technology measures to reduce air pollutants on air quality, human health and climate
European air quality legislation has reduced emissions of air pollutants across Europe since the 1970s,
affecting air quality, human health and regional climate. We used a coupled composition-climate
model to simulate the impacts of European air quality legislation and technology measures
implemented between 1970 and 2010. We contrast simulations using two emission scenarios; one
with actual emissions in 2010 and the other with emissions that would have occurred in 2010 in the
absence of technological improvements and end-of-pipe treatment measures in the energy, industrial
and road transport sectors. European emissions of sulphur dioxide, black carbon (BC) and organic
carbon in 2010 are 53%, 59% and 32% lower respectively compared to emissions that would have
occurred in 2010 in the absence of legislative and technology measures. These emission reductions
decreased simulated European annual mean concentrations of fine particulate matter(PM2.5) by 35%,
sulphate by 44%, BC by 56% and particulate organic matter by 23%. The reduction in PM2.5
concentrations is calculated to have prevented 80 000 (37 000–116 000, at 95% confidence intervals)
premature deaths annually across the European Union, resulting in a perceived financial benefit to
society of US$232 billion annually (1.4% of 2010 EU GDP). The reduction in aerosol concentrations
due to legislative and technology measures caused a positive change in the aerosol radiative effect at
the top of atmosphere, reduced atmospheric absorption and also increased the amount of solar
radiation incident at the surface over Europe. We used an energy budget approximation to estimate
that these changes in the radiative balance have increased European annual mean surface temperatures
and precipitation by 0.45 ± 0.11 °C and by 13 ± 0.8 mm yr−1 respectively. Our results show that the
implementation of European legislation and technological improvements to reduce the emission of
air pollutants has improved air quality and human health over Europe, as well as having an unintended
impact on the regional radiative balance and climate
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