Characterizing Surface Properties of Aggregates Used in Hot Mix Asphalt

Physical and chemical properties of aggregates at the micro scale strongly impact the adhesive bond (strength and durability) between bitumen and aggregate. These properties include surface free energy, chemical interaction potential, and specific surface area. This report describes testing methods developed for the Universal Sorption Device (USD), the Wilhelmy Plate (WP), and the microcalorimeter (MC) to measure these surface properties of aggregates. Test results from five different asphalt binders and nine different aggregates are presented to demonstrate how these surface properties can be used to: (1) select combinations of bitumen and aggregates that are more resistant to moisture damage, (2) select additives that can be used to improve the performance of asphalt mixtures based on the physico-chemical nature of the bitumen and aggregate, and (3) predict the resistance of the mixture to moisture-induced damage.Aggregates Foundation for Technology, Research, and Education (AFTRE)Civil, Architectural, and Environmental Engineerin

Competition & opportunity

Banks and banking ; Banking law ; Regulation Q: Prohibition Against Payment of Interest on Demand Deposits

U.S. monetary policy in an integrating world: 1960 to 2000

Monetary policy ; Federal Open Market Committee ; Monetary policy - United States

A Peer Outreach Initiative to Increase the Registration of Minorities as Organ Donors

Background Black, Asian and minority ethnic (BAME) communities are disproportionately affected by inequalities in transplant services in the UK. There are some indications from pilot programmes that appeals for BAME organ donors may be more effectively communicated by employing grassroots, community-networking approaches, but such initiatives have not been adequately described or evaluated. Methods Lay individuals from BAME communities were trained as peer outreach workers. They attended a series of public events to promote knowledge of organ donation and transplantation among the public. Information was gathered from 806 evaluation forms completed by event attendees at 34 separate events. From these, 54 follow-up interviews were conducted with event attendees who completed evaluation forms, indicated that they intended to sign up to the NHS Organ Donor Register (ODR) within the next month and consented to follow-up. Results Peer outreach initiatives of the type evaluated are associated with increased numbers of BAME people registering as organ donors. A total of 8.8% of event attendees signed up to the NHS ODR. The programme was most effective with people who had previously considered becoming organ donors but who did not know how to go about it. It was less effective with people who had not previously considered it, or who were scared about signing up, or who feared family or religious disapproval. Conclusions Peer outreach programmes with BAME communities can be an effective way of reducing inequalities by increasing the number of people on the NHS ODR and encouraging people to think about the issue

Manual Rubber Sandal Press for Loisaba Kenya

The goal of this project was to develop an inexpensive manual cutting machine to cut sandals out of recycled tires and industrial belt allowing poor Kenya villages to produce their own sandals that are durable enough to survive the rough terrain. In Kenya 56 percent of the population live in poverty, surviving on less than a dollar a day. Walking is the main mode of transportation and the majority of Kenyans can only afford second hand shoes that wear out easily on the unpaved roads. In developing this machine the goal was to make the machine affordable for a company in Kenya to make and sell to local villages who can in turn use this machine to make a profit selling affordable shoes. In the design of this machine special attention was paid to the materials and tools available to manufacture in these poor areas along with the cost of manufacturing. The final design for this press utilized a double toggle linkage to increase a manually applied load. The linkage was modeled after a stone crusher linkage and a mechanical advantage analysis of 3.75 was calculated at the moment the cutting blade contacted the rubber. A simple hollow cube frame was used to support the linkage and a stress simulation analysis was complete which proved a wooden frame would not break under the loading. A prototype was made with basic tools and materials by hand and a sample of tire was successful cut

The influence of riparian invasion by the terrestrial shrub Lonicera maackii on aquatic macroinvertebrates in temperate forest headwater streams

Headwater streams in the midwestern United States are an important ecosystem because they are home to key macroinvertebrate species and serve as the starting point for river systems. According to the river continuum concept, any terrestrial inputs to headwater streams can influence biotic communities and abiotic conditions downstream. Amur honeysuckle (Lonicera maackii) is an invasive shrub species prominent in the midwestern U.S. whose allelopathic properties have proven detrimental to local biodiversity. We hypothesized that increasing L. maackii density along headwater streams would alter the diversity of aquatic macroinvertebrate communities. Five sites located in Montgomery and Miami Counties, Ohio were chosen to represent varying L. maackii density along the banks of headwater streams: one heavily invaded site, two moderately invaded sites, and two reference sites (little to no invasion). This study focused on the EPT taxa (Ephemeroptera, Plectoptera, and Trichoptera), which represent orders of insects whose larvae are known to be sensitive to poor stream water quality. The presence of L. maackii had a significant negative impact on the percentage of EPT individuals. There was no significant effect of L. maackii invasion on the number of families within EPT taxa (EPT Index). We noticed the greatest separation of these metrics as well as macroinvertebrate relative abundance between the heavily invaded site and one reference site. Seasonal effects do not seem to be a significant driver of alterations in EPT assemblages. This study hopes to show that the intensity of L. maackii has effects on macroinvertebrate health, carrying management implications. The results of this study suggest that land managers effectively manage L. maackii invasion so as not to significantly disrupt macroinvertebrate diversity and abundance

UK and EU policy for approval of pesticides suitable for organic systems: Implications for Wales

This study was commissioned by the Welsh Assembly Government (WAG) to review the pesticide approval system in the UK and Europe as far as it affects the use of substances and techniques for crop protection by organic producers in Wales. WAG considers it important that the UK pesticide approval system does not present unnecessary barriers to the development of organic production in Wales. Key Recommendations and scope for further work · WAG should work with the Pesticides Safety Directorate to ensure that the development of pesticide regulatory policy at both National and European level takes full account of the needs of both conventional and organic agriculture and horticulture in the UK. · There is scope for WAG to support the development of a National Pesticide Policy so that regulatory and commercial barriers impeding the development of organic pesticides are minimised. Not only could greater availability of ‘organic pesticides’ have a significant impact on organic production in Wales but there could be important implications for conventional horticulture systems and the use of alternatives to conventional pesticides. · One important regulatory barrier to the registration of ‘organic pesticides’ is the MRL requirement(s) for their approval and this needs to be resolved. Suitable analytical techniques are required to determine firstly whether these substances result in residues, and secondly to identify the breakdown and residue pathways. So far, this issue has not received the attention of any EU Member State. · According to the proposed framework for the 4th Stage Review of EU Pesticides Directive 91/414, notifiers are required to produce a dossier, at their own expense, covering characterisation, human toxicity, ecotoxicity efficacy and other relevant data. The Review includes specific provision for companies notifying the same substance to submit a shared dossier. This will help those businesses (many of which are relatively small companies) to save on the high cost of producing the dossiers. It will also aid the Commission since it will reduce the number of dossiers that have to be considered, and ensure that all the available data is included. WAG should encourage and support the production of collective dossiers; although as yet there is no indication of how this will be done in practice, and further details from the Commission are awaited. · This study has concluded that access to a wider range of ‘organically acceptable pesticides’ would not have a dramatic impact on organic production in Wales. However, in developing an integrated organic policy, WAG should continue to address the pesticides issue. Some of the methods of pest & disease control in organic systems are either physical or multi-cellular e.g. micro-organisms used as biocontrol agents. WAG agri environment policy may provide a vehicle to promote these techniques much more actively. Further, it is important to recognise that while Wales alone is too small to have a major impact on commercial and regulatory pressures, WAG can have an impact by working pro-actively with others to make progress. · There are no published EU or national Member State criteria that can be used to evaluate the acceptability of pesticide substances for organic production. Identifying such criteria and promoting their acceptance at EU level and nationally would allow more active substances to be made available. WAG should work with PSD and others to identify appropriate criteria. · The specific provisions of Article 7 in Annex 2(b) of the Organic Regulation (2092/91) place potential barriers to the adoption of organically acceptable substances for crop protection. There are a number of potentially useful substances currently not included in the Organic Regulation e.g. potassium bicarbonate. WAG should work with PSD and others to identify such substances and support the production of appropriate dossiers. WAG could also encourage further dialogue between the organic sector and Defra to identify amendments in the Organic Regulations to facilitate the inclusion of new pesticides. · Organic pest and disease management is not just a question of inputs but it also relies crucially on advice and extension through initiatives such as Farming Connect and the work of Organic Centre Wales. Long-term commitment to supporting on going advice and extension activities is vital to promote and disseminate best practice in Welsh agriculture and horticulture. · Organic horticulture, vegetable and fruit production systems are particularly sensitive to pest and disease management. Successful control of pests, diseases (and weeds) in these sectors can be critical to the business, and is not assured even when all husbandry and management methods have been effectively applied. Consequently, the use of organically acceptable crop protection methods resulting from future developments (e.g. biopesticides, biological control agents) could have an important role in pest and disease management in these sectors. Both organic and conventional producers in Wales could benefit from having these options available to them and WAG could encourage the adoption of these approaches through appropriate Technology Transfer activities. · The way in which such substances will be regulated at a European level in future is evolving as the review of the Pesticide Directive 91/414 EEC enters the 4th Stage. This stage of the review includes (amongst others) those substances permitted for use in organic production. The guidance documents for the evaluation of applications on plant protection products made from plants or plant extracts and from chemical substances are currently at the draft stage. The response of the Pesticide Safety Directorate and Defra to these developments is not yet clear but this provides an excellent opportunity for WAG to have an input at an early stage in the review process

Propfan Test Assessment (PTA): Flight test report

The Propfan Test Assessment (PTA) aircraft was flown to obtain glade stress and noise data for a 2.74m (9 ft.) diameter single rotation propfan. Tests were performed at Mach numbers to 0.85 and altitudes to 12,192m (40,000 ft.). The propfan was well-behaved structurally over the entire flight envelope, demonstrating that the blade design technology was completely adequate. Noise data were characterized by strong signals at blade passage frequency and up to 10 harmonics. Cabin noise was not so high as to preclude attainment of comfortable levels with suitable wall treatment. Community noise was not excessive

Hot electrons in low-dimensional phonon systems

A simple bulk model of electron-phonon coupling in metals has been surprisingly successful in explaining experiments on metal films that actually involve surface- or other low-dimensional phonons. However, by an exact application of this standard model to a semi-infinite substrate with a free surface, making use of the actual vibrational modes of the substrate, we show that such agreement is fortuitous, and that the model actually predicts a low-temperature crossover from the familiar T^5 temperature dependence to a stronger T^6 log T scaling. Comparison with existing experiments suggests a widespread breakdown of the standard model of electron-phonon thermalization in metals

Engaging Older Youth: Program and City-Level Strategies to Support Sustained Participation in Out-of-School Time

With support from The Wallace Foundation, the Harvard Family Research Project and P/PV conducted a study of almost 200 out-of-school-time (OST) programs in six cities to better understand how they promote sustained participation among older youth.The resulting data indicated that two of the most important practices distinguishing high-retention programs were: ample leadership opportunities for youth and high levels of staff efforts to keep informed about participants' lives outside the programs. The study also compares and contrasts effective practices for middle school- versus high school-aged youth, noting the shortcomings of "one-size-fits-all" strategies. Finally, Engaging Older Youth details the influence of city-level OST initiatives on programs and identifies the types of city-level services that likely support participation