10,377 research outputs found
America's North Coast: A Benefit-Cost Analysis of a Program to Protect and Restore the Great Lakes
Examines the baseline ecological conditions of the Great Lakes and offers a plan for the area's environmental protection and restoration. Demonstrates how a restoration program can provide economic benefits that substantially exceed its costs
Reply to ``Comment on `Insulating Behavior of -DNA on the Micron Scale' "
In our experiment, we found that the resistance of vacuum-dried -DNA
exceeds at 295 K. Bechhoefer and Sen have raised a number of
objections to our conclusion. We provide counter arguments to support our
original conclusion.Comment: 1 page reply to comment, 1 figur
A high efficiency, low background detector for measuring pair-decay branches in nuclear decay
We describe a high efficiency detector for measuring electron-positron pair
transitions in nuclei. The device was built to be insensitive to gamma rays and
to accommodate high overall event rates. The design was optimized for total
pair kinetic energies up to about 7 MeV.Comment: Accepted for publication by Nucl. Inst. & Meth. in Phys. Res. A (NIM
A
Selective Pressure of Antibiotic Pollution on Bacteria of Importance to Public Health
Background: Many bacteria of clinical importance survive and may grow in different environments. Antibiotic pollution may exert on them a selective pressure leading to an increase in the prevalence of resistance. Objectives: In this study we sought to determine whether environmental concentrations of antibiotics and concentrations representing action limits used in environmental risk assessment may exert a selective pressure on clinically relevant bacteria in the environment. Methods: We used bacterial inhibition as an assessment end point to link antibiotic selective pressures to the prevalence of resistance in bacterial populations. Species sensitivity distributions were derived for three antibiotics by fitting log-logistic models to end points calculated from minimum inhibitory concentration (MIC) distributions based on worldwide data collated by the European Committee on Antimicrobial Susceptibility Testing (EUCAST). To place bacteria represented in these distributions in a broader context, we performed a brief phylogenetic analysis. The potentially affected fraction of bacterial genera at measured environmental concentrations of antibiotics and environmental risk assessment action limits was used as a proxy for antibiotic selective pressure. Measured environmental concentrations and environmental risk assessment action limits were also directly compared to wild-type cut-off values. Results: The potentially affected fraction of bacterial genera estimated based on antibiotic concentrations measured in water environments is ≤ 7%. We estimated that measured environmental concentrations in river sediments, swine feces lagoons, liquid manure, and farmed soil inhibit wild-type populations in up to 60%, 92%, 100%, and 30% of bacterial genera, respectively. At concentrations used as action limits in environmental risk assessment, erythromycin and ciprofloxacin were estimated to inhibit wild-type populations in up to 25% and 76% of bacterial genera. Conclusions: Measured environmental concentrations of antibiotics, as well as concentrations representing environmental risk assessment action limits, are high enough to exert a selective pressure on clinically relevant bacteria that may lead to an increase in the prevalence of resistance
Inclusion and Independence: The impact of Mobile Technology on the Lives of Persons with Disabilities in Kenya and Bangladesh
Globally, mobile technology plays a significant role connecting and supporting people with disabilities. However, there has been limited research focused on understanding the impact of mobile technology in the lives of persons with disabilities in low or middle- income countries. This paper presents the findings of a participatory photovoice study looking at the role that mobile phones play in the daily lives of 16 persons with disabilities in Kenya and Bangladesh. Participants used a combination of pictures and voice recordings to capture their own stories and illustrate the impact that mobile phone use has on their lives. Through thematic analysis, we categorized the benefits of mobile phones captured by participants as 1) Improved social connection; 2) Increased independence and 3) Access to opportunities. While mobile phones are ubiquitously used for communication, for persons with disabilities they become essential assistive technologies that bridge barriers to opportunities which are not accessible otherwise. Our paper adds evidence to the need for mobile phones for persons with disabilities to enable communication and connectivity in support of development
Shielding effectiveness of non-woven carbon fibre sheets : modelling the microstructure
This paper describes work undertaken to understand how the structure of a nonwoven carbon fibre material determines its shielding effectiveness, including the effects of fibre orientation, and contact resistance. In order to facilitate understanding of the material behaviour, software has been written to generate Monte Carlo Models (MCMs) of the material structure. The results of our MCMs are compared with measurements and some empirical expressions
- …