7,994 research outputs found
Testosterone Therapy and Cardiovascular Risk
Endogenous testosterone levels are inversely associated with cardiovascular risk in older men and men with cardiovascular disease. Current data on cardiovascular outcomes of testosterone therapy include only observational studies and adverse event monitoring in short-term trials that were not designed to measure cardiovascular outcomes. These studies have yielded conflicting results, and some have raised concerns that testosterone therapy may increase cardiovascular risk. A well-designed, adequately powered, prospective trial will ultimately be required to clarify whether testosterone therapy impacts cardiovascular outcomes. This review describes the findings and limitations of recent studies of cardiovascular risk in older men on testosterone therapy and discusses some of the mechanisms through which testosterone may modify cardiovascular risk
Night on Fire: The First Complete Account of John Paul Jones\u27 Greatest Battle, and We Have Met the Enemy: Oliver Hazard Perry: Wilderness Commodore
The Coercive Logic of Militant Drone Use
While unmanned aerial systems can serve as a force multiplier for militants, these systems do not embody a transformation in modern insurgent warfare or enable militants to engage regularly in strategic coercion. Instead, drone use is consistent with a militant group’s relative capabilities and broader strategic objectives. Consequently, these groups are likely to employ drones primarily for theater and tactical military purposes
A Farm-Level Evaluation of Conditions Under Which Farmers Will Supply Biomass Feedstocks for Energy Production
This study evaluated the risk management potential of including biomass crops as a diversification strategy for a grain farm in northwest Tennessee. Results indicate that adding biomass crops to the farm enterprise mix could improve mean net revenues and reduced net revenue variability.Resource /Energy Economics and Policy,
On-Line Realtime Water Quality Monitoring and Control for Swimming Pools
Effective swimming pool water quality monitoring and control systems are important to safeguard public health and for bather comfort. Most Irish swimming pool monitoring systems rely heavily on manual methods for sampling, testing and data recording of important parameters. Microbiological testing is infrequent and results can often take days. The goal of this research is to develop a water quality monitoring and control system with real time data logging, automatic data analysis, remote monitoring and control, microbiological sampling capabilities and online connectivity. National Instruments hardware and its software package LabView form the basis of the monitoring and control system. Several sensors measure the main water parameters affecting disinfection and overall water balance: temperature, pH level, total dissolved solids, turbidity, chlorine level and redox potential. Water hardness is measured manually due to the prohibitive cost of an automatic system. The LabView package and related hardware controls the chemical dosing of the pool in order to maintain these parameters within their recommended optimum levels. An investigation is also being carried out into the development of a biosensor to detect E. coli, as it is the best indicator of faecal contamination in water. The flexibility of the technology used in this research means that it has numerous other potential applications, such as: drinking water treatment, waste water treatment, industrial process control, environmental study and monitoring
A Multicenter Study Of Students Sensitivity To Screen-Update Delay
In a climate of shrinking educational budgets, online learning courses offer many advantages; however there are several possible problems associated with electronic learning. There may be problems associated with learning style preferences, student apathy, instructional support, accessibility, and problems with technology. This paper examines a technological problem associated with the effects of screen-update-delay and student enjoyment, student self-reported comprehension, and student objective comprehension. In particular, this paper attempts to identify the point at which longer screen updates will be detrimental to the students enjoyment and/or have a significant negative impact on the students self-reported comprehension and retention of material
Trends and biases in the listing and recovery planning for threatened species: an Australian case study
Many countries rely on formal legislation to protect and plan for the recovery of threatened species. Even though the listing procedures in threatened species legislation are designed to be consistent for all species there is usually a bias in implementing the laws towards charismatic fauna and flora, which leads to uneven allocation of conservation efforts. However, the extent of bias in national threatened species lists is often unknown. Australia is a good example: the list of threatened species under the Environmental Protection and Biological Conservation Act has not been reviewed since 2000, when it was first introduced. We assessed how well this Act represents threatened species across taxonomic groups and threat status, and whether biases exist in the types of species with recovery plans. We found that birds, amphibians and mammals have high levels of threatened species (12-24%) but < 6% of all reptiles and plants and < 0.01% of invertebrates and fish are considered threatened. Similar taxonomic biases are present in the types of species with recovery plans. Although there have been recent improvements in the representation of threatened species with recovery plans across taxonomic groups, there are still major gaps between the predicted and listed numbers of threatened species. Because of biases in the listing and recovery planning processes many threatened species may receive little attention regardless of their potential for recovery: a lost opportunity to achieve the greatest conservation impact possible. The Environmental Protection and Biological Conservation Act in Australia needs reform to rectify these biases
Monitoring of zincate pre-treatment of aluminium prior to electroless nickel plating
<p>Zincating is used as a pre-treatment for aluminium prior to electroless nickel deposition during preparation of magnetic computer memory discs. Four immersion zincating solutions were evaluated at 22°C using single step or double zincating followed by electroless nickel deposition from a high phosphorus hypophosphite bath at 90°C. The coating process was monitored by potential <i>vs.</i> time curves obtained under open-circuit conditions during zincating then electroless nickel plating. The surface morphology of the aluminium, at various stages, was imaged by scanning electron microscopy and atomic force microscopy. Zero resistance ammetry was used to record galvanic currents between the aluminium and an inert platinum counter electrode during zincating. This, together with potential-time measurements, provided simple and valuable methods for following the zincating process and subsequent electroless Ni plating. Double zincating enabled a shorter induction time for electroless Ni deposition and resulted in a more complete coverage of the surface by Zn.</p
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Enzymatic Glycosylation of Vancomycin Aglycon: Completion of a Total Synthesis of Vancomycin and N- and C-Terminus Substituent Effects of the Aglycon Substrate
Studies on the further development of the sequential glycosylations of the vancomycin aglycon catalyzed by the glycosyltransferases GtfE and GtfD and the observation of unusual, perhaps unexpected, aglycon substrate substituent effects on the rate and efficiency of the initial glycosylation reaction are reported
Global protein responses of multidrug resistance plasmid-containing Escherichia coli to ampicillin, cefotaxime, imipenem and ciprofloxacin
Objectives
This study compared the proteomics of Escherichia coli containing the multidrug resistance plasmid pEK499 under antimicrobial stress and with no antimicrobial.
Methods
We utilised mass spectrometry-based proteomics to compare the proteomes of the bacteria and plasmid under antimicrobial stress and no antimicrobial.
Results
Our analysis identified statistically significant differentially abundant (SSDA) proteins common to groups exposed to the β-lactam antimicrobials but not ciprofloxacin, indicating a β-lactam stress response to exposure from this class of drugs, irrespective of β-lactam resistance or susceptibility. Data arising from comparisons of the proteomes of ciprofloxacin-treated E. coli and controls detected an increase in the relative abundance of proteins associated with ribosomes, translation, the TCA cycle and several proteins associated with detoxification, and a decrease in the relative abundance of proteins associated with the stress response, including oxidative stress. We identified changes in proteins associated with persister formation in the presence of ciprofloxacin but not the β-lactams. The plasmid proteome differed across each treatment and did not follow the pattern of antimicrobial–antimicrobial resistance (AMR) protein associations: a relative increase was observed in the amount of CTX-M-15 in the presence of cefotaxime and ciprofloxacin, but not the other β-lactams, suggesting regulation of CTX-M-15 protein production.
Conclusion
The proteomic data from this study provided novel insights into the proteins produced from the chromosome and plasmid under different antimicrobial stresses. These data also identified novel proteins not previously associated with AMR or antimicrobial responses in pathogens, which may well represent potential targets of AMR inhibition
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