674 research outputs found
Engineering scale-up challenges, and effects of SO2 on the calcium looping cycle for post combustion CO2 capture
Engineering scale-up challenges, and potential effects of SO2 on the calcium looping cycle for post combustion CO2 capture have been investigated in Cranfield University's pilot scale reactor (25 kWth). Following reactor and process modifications, close to 80% capture was achieved. SO2 was found to have a detrimental effect on the calcium looping cycle in both batch and continuous cyclic tests, although the presence of steam from natural gas-fired burners was found to have a positive effect on maintaining capture capacity of the sorbent
A Qualitative Examination of Graduate Advising Relationships:The Advisee Perspective
Sixteen 3rd-year counseling psychology doctoral students were interviewed about their relationships with their graduate advisors. Of those students, 10 were satisfied and 6 were unsatisfied with their advising relationships. Satisfied and unsatisfied students differed on several aspects of the advising relationship, including (a) the ability to choose their advisors, (b) the frequency of meetings with their advisors, (c) the benefits and costs associated with their advising relationships, and (d) how conflict was dealt with in the advising relationship. Furthermore, all of the satisfied students reported that their advising relationships became more positive over time, whereas many of the unsatisfied students reported that their advising relationships got worse (e.g., became more distant) over time
A Comparison of Occupied and Unoccupied Sharp-Tailed Grouse Habitat in Montana
The sharp-tailed grouse (Tympanuchus phasianellus) was once present throughout the state of Montana. The species was extirpated in Montana west of the Continental Divide by the late 2000ās, while healthy populations still exist east of the Continental Divide. We compared key habitat components important to sharp-tailed grouse survival in occupied areas east of the Divide to unoccupied areas west of the Divide. We measured vegetative variables related to nesting, brood-rearing, and wintering habitat requirements in 3 occupied study areas and 4 unoccupied study areas during the spring of 2015. Habitat Suitability Index scores were calculated for nesting and brood-rearing. Habitat Suitability Index averages show habitat in the Blackfoot valley to be most suitable for sustaining a sharp-tailed grouse population, habitat in the Bitterroot valley to be potentially suitable, and habitat in Drummond and in the Mission Valley to be unsuitable at this time. These results suggest that the Blackfoot and Bitterroot valleys may contain suitable habitat for a potential sharp-tailed grouse reintroduction
Effects of Fructose-Derived Advanced Glycation End Products on Acetylation of Histones in the Brain
Objective: The objective of this study was to determine the effects of fructose and their advanced glycation end products (fru-AGES) on histone acetylation in microglia, the immune cells of the brain.
Significance: Fru-AGES primarily form as a result of non-enzymatic reactions between fructose and proteins. One result is inflammation in the brain, which can be directly correlated to increased microglia activity. Microglial activity has been shown to be associated with the acetylation of histones, resulting in a change in transcription of inflammatory genes. Elucidation of a direct link between fructose, fru-AGES and histone acetylation would increase understanding the pathophysiology of inflammatory disorders such as Alzheimerās disease.
Experimental Procedures: An immortalized rat microglial cell line was treated in vitro with control media, fru-AGES or fructose. Histone acetylation was analyzed indirectly through activity of histone deacetlyase (HDAC) using the HDAC Glo I/II Assay (Promega). Chemiluminescent product formation was measuring with a spectrophotometer.
Results Obtained: Both treatments with fructose and fru-AGES showed an increase in HDAC activity compared to control by up to 35% and 20%, respectively, correlating to a decrease in global histone acetylation. This is contradictory to initial expectations, as a decrease in acetylation could result in a decrease in transcription of genes . Despite causing an initial inflammatory response, fructose and fru-AGES appear to suppress overall gene transcription.
Conclusion: Previous data show that exposure of microglia to fructose and fru-AGES results in a pro-inflammatory activated state. However, at the level of gene transcription, microglia may be desensitized and less able to respond in the long term
Perceptions of personal health risks by medical and non-medical workers in a university medical center: a survey study
<p>Abstract</p> <p>Background</p> <p>Health care workers (HCWs) are faced with many work-related choices which may depend on how they perceive risk, such as whether or not to comply with safety regulations. Little research has investigated risk perception in medical workers in comparison with non-medical workers and the extent to which risk perception differs in these groups. The current study thus investigates risk perception of medical and non-medical workers to inform and complement future research on safety compliance. The study has implications for the design of intervention programmes to increase the level of compliance of HCWs.</p> <p>Methods</p> <p>A survey study was conducted in which questionnaires were distributed to 6380 HCWs. The questionnaire asked for ratings of risk perception for cold, annual influenza, pandemic influenza, cancer, heart attack and food poisoning. Of 2495 returned questionnaires (response rate: 39%), 61.40% were from medical workers (24.1% of these were from physicians, 39.7% from nurses and 36.2% from paramedics) and 38.60% were from non-medical workers.</p> <p>Results</p> <p>Medical workers gave lower risk perception ratings than did non-medical workers for cancer, but not for other health risks. Within the medical workers, physicians rated the risk of getting a cold as higher, but of having a heart attack as lower than did nurses and paramedics; physicians also rated their risk of getting cancer as lower than did nurses. Perceived risk was higher as a function of age for pandemic influenza, cancer and heart attack, but lower for cold and annual influenza. HCWs who lived with a partner and children rated the risk of getting a cold or annual influenza higher than those who lived alone or with a partner only. Full-time HCWs gave lower ratings for annual influenza than did part-time HCWs.</p> <p>Conclusions</p> <p>Different base levels of risk perception between medical and non-medical workers need to be taken into account for successful implementation of safety regulations.</p> <p>Intervention programmes to improve compliance with safety regulations may need to be customized for different groups as a function of how they perceive risk.</p
Habitat change and the scale of predation risk
In their efforts to maximise fitness while reducing the probability of dying, animals must trade off food for safety. The trade-off is likely to depend on habitat and habitat change. I imagine an environment with both safe and risky (manipulated) patches in which foragers can respond by altering their pattern of foraging, by avoidance, or by reduced activity. Analytical models predict that if foragers exploit risky patches, predation risk will either increase with distance from safety, or with the area foraged. But if foragers avoid risky patches, predation risk will either decelerate or decline sigmoidally with area away from the risky patch
Dynamic Modeling of In-Use Cement Stocks in the United States
A dynamic substance-flow model is developed to characterize the stocks and flows of cement utilized during the 20th century in the United States, using the generic cement life cycle as a systems boundary. The motivation for estimating historical inventories of cement stocks and flows is to provide accurate estimates of contemporary cement in-use stocks in U.S. infrastructure and future discards to relevant stakeholders in U.S. infrastructure, such as the federal and state highway administrators, departments of transportation, public and private utilities, and the construction and cement industries. Such information will assist in planning future rehabilitation projects and better life cycle management of infrastructure systems. In the present policy environment of climate negotiations, estimates of in-use cement infrastructure can provide insights about to what extent built environment can act as a carbon sink over its lifetime. The rate of addition of new stock, its composition, and the repair of existing stock are key determinants of infrastructure sustainability. Based upon a probability of failure approach, a dynamic stock and flow model was developed utilizing three statistical lifetime distributionsāWeibull, gamma, and lognormalāfor each cement end-use. The model-derived estimate of the āin-useā cement stocks in the United States is in the range of 4.2 to 4.4 billion metric tons (gigatonnes, Gt). This indicates that 82% to 87% of cement utilized during the last century is still in use. On a per capita basis, this is equivalent to 14.3 to 15.0 tonnes of in-use cement stock per person. The in-use cement stock per capita has doubled over the last 50 years, although the rate of growth has slowed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72233/1/JIEC_055_sm_SuppMat.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/72233/2/j.1530-9290.2008.00055.x.pd
Systemic implications of the bail-in design
The 2007-2008 financial crisis forced governments to choose between the unattractive alternatives of either bailing out a systemically important bank (SIB) or allowing it to fail disruptively. Bail-in has been put forward as an alternative that potentially addresses the too-big-to-fail and contagion risk problems simultaneously. Though its efficacy has been demonstrated for smaller idiosyncratic SIB failures, its ability to maintain stability in cases of large SIB failures and system-wide crises remains untested. This paperās novelty is to assess the financial-stability implications of bail-in design, explicitly accounting for the multilayered networked nature of the financial system. We present a model of the European financial system that captures all five of the prevailing contagion channels. We demonstrate that it is essential to understand the interaction of multiple contagion mechanisms and that financial institutions other than banks play an important role. Our results indicate that stability hinges on the bank-specific and structural bail-in design. On one hand, a welldesigned bail-in buttresses financial resilience, but on the other hand, an ill-designed bail-in tends to exacerbate financial distress, especially in system-wide crises and when there are large SIB failures. Our analysis suggests that the current bail-in design may be in the region of instability. While policy makers can fix this, the political economy incentives make this unlikely
Systematic Heuristic Evaluation of Computerized Consultation Order Templates: Cliniciansā and Human Factors Engineersā Perspectives
We assessed the usability of consultation order templates and identified problems to prioritize in design efforts for improving referral communication. With a sample of 26 consultation order templates, three evaluators performed a usability heuristic evaluation. The evaluation used 14 domain-independent heuristics and the following three supplemental references: 1 new domain-specific heuristic, 6 usability goals, and coded cliniciansā statements regarding ease of use for 10 sampled templates. Evaluators found 201 violations, a mean of 7.7 violations per template. Minor violations outnumbered major violations almost twofold, 115 (57%) to 62 (31%). Approximately 68% of violations were linked to 5 heuristics: aesthetic and minimalist design (17%), error prevention (16%), consistency and standards (14%), recognition rather than recall (11%), and meet referrersā information needs (10%). Severe violations were attributed mostly to meet referrersā information needs and recognition rather than recall. Recorded violations yielded potential negative consequences for efficiency, effectiveness, safety, learnability, and utility. Evaluators and clinicians demonstrated 80% agreement in usability assessment. Based on frequency and severity of usability heuristic violations, the consultation order templates reviewed may impede clinical efficiency and risk patient safety. Results support the following design considerations: communicate consultantsā requirements, facilitate information seeking, and support communication. While the most frequent heuristic violations involved interaction design and presentation, the most severe violations lacked information desired by referring clinicians. Violations related to templatesā inability to support referring cliniciansā information needs had the greatest potential negative impact on efficiency and safety usability goals. Heuristics should be prioritized in future design efforts
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