585 research outputs found
Security Analysis, Agency Costs, and UK Firm Characteristics
This paper assesses the monitoring power of security analysts from the manager-shareholder conflict perspective. Using a sample of UK firms tracked by security analysts, our evidence supports the view that security analysis acts as a monitoring mechanism in reducing agency costs. We also find that security analysts are more effective in reducing agency costs for smaller and more focused firms rather than larger and more diversified firms suggesting that for larger and more complex firms security analysis is less effective. The UK findings suggest that the monitoring role of security analysts is not restricted to the U.S. capital market environment.
Solids maldistribution in parallel cyclones
The amount of solids maldistribution in parallel cyclones was investigated to determine what parameters affected the maldistribution. In many fluidized bed processes with parallel cyclones (as many as 20 in parallel in some cases), it has been noted that unequal erosion (wear) can occur in the cyclones. This results in very short run lengths in order to repair the cyclones with the most wear. This unequal wear has been attributed to unequal solids distribution to the cyclones. In addition to the increased wear, cyclone efficiencies are affected as well.
In the specific concern that generated this study, it was found that parallel cyclones in fluidized-bed cokers at Syncrude Canada Ltd. (Syncrude) had unequal amounts of coke buildup on them. This coke buildup on the cyclones causes increased backpressure on the fluidized-bed coker, and after a certain pressure is reached, results in shutdown of the coker. Hot scouring coke, presented at the cyclone inlets, is used to combat the coke formation that is caused by condensation of heavy hydrocarbons. Understanding the scouring coke distribution into the parallel cyclones could lead to reduced deposit maldistribution and increased run length.
The testing to determine what causes solids maldistribution in parallel cyclones was conducted using four, 30-cm diameter parallel cyclones that were located above a 0.9-m diameter fluidized bed. Solids flows into the freeboard above the fluidized bed were from the fluidized bed itself and from two pneumatic conveying lines that simulated the lines entering the freeboard of the Syncrude Canada Ltd (Syncrude) fluidized bed coker. The testing was conducted at ambient temperature and pressure using a coke material with a median particle size of 156 microns.
The results of the testing showed that although the pressure drop across the cyclones were essentially equal, the gas and solids flow rates through the cyclones could vary significantly. By closing a valve in the dipleg of each of the test cyclones and measuring the rate of buildup of solids in each dipleg, the solids flow rate through each cyclone could be determined.
Tests were conducted to vary the gas flow rate through the bed, the amount of solids flow through each pneumatic conveying line and the amount of gas flowing through each cyclone. Depending on conditions, it was found that the ratio of the solids flow rate through the highest-loaded cyclone to the lowest-loaded cyclone could be as much as a factor of four.
It was found that the solids distribution in the freeboard above the bed determined the solids flow distribution into each cyclone. Changing the gas flow rate through the cyclone did not affect the solids distribution through the cyclones. It appears that the solids distribute to the cyclones based on the solids distribution at the entrance to the parallel cyclones. The gas flow then distributes itself in order to equalize the pressure drop across the cyclones
Long-term ecological research and the COVID-19 anthropause: A window to understanding social-ecological disturbance
The period of disrupted human activity caused by the COVID-19 pandemic, coined the anthropause, altered the nature of interactions between humans and ecosystems. It is uncertain how the anthropause has changed ecosystem states, functions, and feedback to human systems through shifts in ecosystem services. Here, we used an existing disturbance framework to propose new investigation pathways for coordinated studies of distributed, long-term social-ecological research to capture effects of the anthropause. Although it is still too early to comprehensively evaluate effects due to pandemic-related delays in data availability and ecological response lags, we detail three case studies that show how long-term data can be used to document and interpret changes in air and water quality and wildlife populations and behavior coinciding with the anthropause. These early findings may guide interpretations of effects of the anthropause as it interacts with other ongoing environmental changes in the future, particularly highlighting the importance of long-term data in separating disturbance impacts from natural variation and long-term trends. Effects of this global disturbance have local to global effects on ecosystems with feedback to social systems that may be detectable at spatial scales captured by nationally to globally distributed research networks
Ethnic differences in Glycaemic control in people with type 2 diabetes mellitus living in Scotland
Background and Aims:
Previous studies have investigated the association between ethnicity and processes of care and intermediate outcomes of diabetes, but there are limited population-based studies available. The aim of this study was to use population-based data to investigate the relationships between ethnicity and glycaemic control in men and women with diabetes mellitus living in Scotland.<p></p>
Methods:
We used a 2008 extract from the population-based national electronic diabetes database of Scotland. The association between ethnicity with mean glycaemic control in type 2 diabetes mellitus was examined in a retrospective cohort study, including adjustment for a number of variables including age, sex, socioeconomic status, body mass index (BMI), prescribed treatment and duration of diabetes.<p></p>
Results:
Complete data for analyses were available for 56,333 White Scottish adults, 2,535 Pakistanis, 857 Indians, 427 Chinese and 223 African-Caribbeans. All other ethnic groups had significantly (p<0.05) greater proportions of people with suboptimal glycaemic control (HbA1c >58 mmol/mol, 7.5%) compared to the White Scottish group, despite generally younger mean age and lower BMI. Fully adjusted odds ratios for suboptimal glycaemic control were significantly higher among Pakistanis and Indians (1.85, 95% CI: 1.68â2.04, and 1.62,95% CI: 1.38â1.89) respectively.<p></p>
Conclusions:
Pakistanis and Indians with type 2 diabetes mellitus were more likely to have suboptimal glycaemic control than the white Scottish population. Further research on health services and self-management are needed to understand the association between ethnicity and glycaemic control to address ethnic disparities in glycaemic control.<p></p>
Improved Standpipe Entrance for Stable High-Flux Flow
Cold model tests were used to show the causes of instabilities in the operation of the standpipe entrance (âsore thumbâ) in industrial scale fluid cokers. New geometries were tested which might provide higher flows and prevent operating problems such as flow reversals and flooding, while also minimizing the adverse effects of fouling. The tests were conducted using FCC particles in a geometrically and dynamically scaled half-column of approximately 1/9th scale which had previously been used to show the effects of baffles on fluid coker strippers. The addition of sloping surfaces to increase the surface area for ingress of particles was helpful to an extent, but excessive overhang resulted in bubbles being drawn in. A perforated top surface was found to be instrumental in the degassing of the solids, whereas porous side area was essential for solids entry. Aeration of the standpipe reduced stick-slip flow, but excessive aeration made degassing more difficult and therefore promoted flow reversal. Loss of area at the top, and to a lesser extent, at the sides was found to be detrimental to the performance of the standpipe entrance. Several new geometries were tested, leading to one that provided better flow stability, improved flow control, excellent pressure build-up in the standpipe, more tolerance to fouling, and enhanced circulation capacity
Marked improvement in HbA<sub>1c</sub> following commencement of flash glucose monitoring in people with type 1 diabetes
Egg and clutch sizes of western chicken turtles (Deirochelys reticularia miaria)
Chicken turtles (Deirochelys reticularia) are generally characterized as having atypical reproductive characteristics relative to other sympatric emydids. However, the comparatively understudied western chicken turtle (D. r. miaria) has been shown to exhibit some reproductive characteristics that differ from the other subspecies. Therefore, we examined clutch and egg sizes from six D. r. miaria (13 clutches) in Oklahoma and compared the results to values that have been reported for the other two subspecies. Females nested up to three times per year, with clutches ranging from 8-13 eggs per clutch (mean = 10.9). The eggs were 19.4-25.3 mm wide (mean = 22.2 mm). These values are greater than the means reported for the other subspecies, but the differences were not statistically significant
HbA1c response and hospital admissions following commencement of flash glucose monitoring in adults with type 1 diabetes
Introduction Our aim was to assess the effect of introducing flash monitoring in adults with type 1 diabetes with respect to change in hemoglobin A1c (HbA1c) and frequency of hospital admissions.Research design and methods Prospective observational study of adults with type 1 diabetes in our center, in whom a prescription for a flash monitoring sensor was collected. Primary outcome was change in HbA1c between 2016 and after flash monitoring. Rates of hospital admission were compared between the first year after flash monitoring and the corresponding 12-month period 2 years earlier.Results Approximately half of all adults with type 1 diabetes, attending our center, collected prescriptions for flash monitoring sensors (n=2216). Median fall in HbA1c was â1 (â0.1) mmol/mol (%) (p<0.001) and was greatest in those with baseline HbA1c >75 (9.0) mmol/mol (%): â10 (â0.9) mmol/mol (%), p<0.001. 43% of those with a baseline HbA1c >53âmmol/mol (7%) experienced a â„5âmmol/mol (0.5%) fall in HbA1c. In addition to higher HbA1c, early commencement within 1âmonth of NHS-funded flash monitoring (p<0.001), and male gender (p=0.013) were associated with a fall in HbA1c of â„5 (0.5) mmol/mol (%). Socioeconomic deprivation (p=0.009) and collecting fewer than 2 sensors per month (p=0.002) were associated with lack of response. Overall, hospital admissions did not change but an increase in admissions for hypoglycemia was observed (1.1% vs 0.3%, p=0.026).Conclusions Flash monitoring is associated with reduction in HbA1c in individuals with HbA1c >58âmmol/mol. Numerous clinical features are independently associated with HbA1c response. An increase in hypoglycemia admissions occurred following flash monitoring
Electronic books in public libraries: a feasibility study for developing usage models for web-based and hardware-based electronic books
This final report considers the background and implementation of a project that
introduced electronic book (ebook) collections to Essex Public Libraries in 2004. The
research considered ebook collections available for borrowing on a PDA (HP iPAQ)
and collections downloadable on to the borrowerâs PDA or PC (OverDrive, ebrary).
The project, a partnership consisting of Loughborough University, Essex Public
Libraries, and the Co-East Management Team
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