406 research outputs found
Editor's Note
An update on the Alaska Justice Forum during times of change at the University of Alaska Anchorage, including the publication's transition to an all-digital format
Environmental test program for superconducting materials and devices
A systematic approach to obtaining real time, superconducting YBa2Cu30(7-x) materials is presented. The work was carried out under the overall direction of Clemson University with tasks being performed at both Clemson and Westinghouse (Aiken, SC). Clemson prepared the tapecast superconducting 123 material and fabricated in into substrate-supported, environmentally-protected conducting links. Following this, all of the elements were individually tested for resistance vs. temperature and Tc; and then a portion of them were kept at Clemson for further testing while a randomly selected group was delivered to Westinghouse for specialized testing and evaluation in their low temperature/high vacuum and radiation facilities. In addition, a number of control samples (12 ea.) were put on the shelf at Clemson for further reference at the end of the testing period. The specific tests conducted at Clemson and Westinghouse/SRC are presented with a summary of the results
Enhancement of cooling tower performance by manipulation of rain zone drop size
Thesis (MEng)--University of Stellenbosch, 1995.AFRIKAANSE OPSOMMING: Die moontlikheid om die warmteoordrag in die reensone van 'n natuurlike trek nat koeltoring
te vcrbeter deur die gemiddelde druppel diameter van die sproei te verminder is ondersoek.
Eksperimentele wcrk was daarop gerig om tipiese druppelgrootte verspreidings onder
druppakking te bepaal, asook die verkryging van werklike verrigtings-data vir verskiJlende
pakking en reensone kombinasies in 'n koeltoring toetsfasiliteit. 'n Fotografiese metode wat
gebruik maak van beeldverwerkingstegniekc is ontwikkel om die druppelgrootte verspreidings
wat in die )meltoring toetsfasiliteit gevind word te bepaal. 'n Rekenaar simulasieprogram wat
ontwikkel is deur Dreyer [940Rl] is verder gebruik om reensone verrigtingsdata
( oordragskarakteristieke en druppelgrootte verspreidings) teoreties te vcorspel, vir vergelyking
met en evalusie van die eksperimentele resultate.
Dit is bewys dat die plasing van 'n laag spatroosters reg onder druppakking die gerniddelde
druppeldiameter in die reensone verrninder het, wat gelei het tot 'n ooreenstemmende toename
in oordragskarakteristiek. Met die gebruik van 'n rekenaar simulasie program is bereken dat
hierdie opstelling die termiese kapasiteit van 'n koeltoring met tot 5 % kan verbeter.ENGLISH ABSTRACT: The possibility of improving the heat transfer in the rain zone of large natural draft wet cooling
towers, by decreasing the mean drop diameter in this region, has been investigated.
Experimental studies were aimed at determining typical drop size distributions under trickle
packs and obtaining actual performance data for packing and rain zone combinations in a
cooling tower test facility. A photography-based method, which utilizes image processing
techniques, was develo!Jed t() determine the drop size distributions found in the test facility. A
computer simulation program developed by Dreyer [94DRI] was used to theoretically predict
rain zone performance data (i.e., transfer coefficients and drop size distribution data) for
comparison with and evaluation of the experimental data.
I: was found that by placing a layer of splash grids beneath a trickle pack the mean drop
diameter in the rain zone was decreased, resulting in corresponding increases in transfer
characteristic. Using a computer simulation program it was calculated that this arrangement
could increase the thermal capacity of a large natural draft cooling tower by up to 5 %
National variation in United States sepsis mortality: a descriptive study
<p>Abstract</p> <p>Background</p> <p>The regional distribution of a disease may provide important insights regarding its pathophysiology, risk factors and clinical care. While sepsis is a prominent cause of death in the United States (US), few studies have examined regional variations with this malady. We identified the national variation in sepsis deaths in the US. We conducted a descriptive analysis of 1999-2005 national vital statistics data from the National Center for Health Statistics summarized at the state-level. We defined sepsis deaths as deaths attributed to an infection, classified according to the International Classification of Diseases, Version 10. We calculated national and state age-adjusted sepsis-attributed mortality rates.</p> <p>Results</p> <p>National age-adjusted sepsis mortality was 65.5 per 100,000 persons (95% CI: 65.8 - 66.0). State level sepsis mortality varied more than two-fold (range 41 to 88.6 per 100,000 persons; median 60.8 per 100,000, IQR 53.9-74.4 per 100,000). A cluster extending from the Southeastern to the mid-Atlantic US encompassed states with the highest sepsis mortality.</p> <p>Conclusions</p> <p>Sepsis mortality varies across the US. The states with highest sepsis mortality form a contiguous cluster in the Southeastern and mid-Atlantic US. These observations highlight unanswered questions regarding the characteristics and care of sepsis.</p
Is the outpatient management of acute diverticulitis safe and effective? A systematic review and meta-analysis
Background: In Western countries, the incidence of acute diverticulitis (AD) is increasing. Patients with uncomplicated diverticulitis can undergo a standard antibiotic treatment in an outpatient setting. The aim of this systematic review was to assess the safety and efficacy of the management of acute diverticulitis in an outpatient setting. Methods: A literature search was performed on PubMed, Scopus, Embase, Central and Web of Science up to September 2018. Studies including patients who had outpatient management of uncomplicated acute diverticulitis were considered. We manually checked the reference lists of all included studies to identify any additional studies. Primary outcome was the overall failure rates in the outpatient setting. The failure of outpatient setting was defined as any emergency hospital admission in patients who had outpatient treatment for AD in the previous 60 days. A subgroup analysis of failure was performed in patients with AD of the left colon, with or without comorbidities, with previous episodes of AD, in patients with diabetes, with different severity of AD (pericolic air and abdominal abscess), with or without antibiotic treatment, with ambulatory versus home care unit follow-up, with or without protocol and where outpatient management is a common practice. The secondary outcome was the rate of emergency surgical treatment or percutaneous drainage in patients who failed outpatient treatment. Results: This systematic review included 21 studies including 1781 patients who had outpatient management of AD including 11 prospective, 9 retrospective and only 1 randomized trial. The meta-analysis showed that outpatient management is safe, and the overall failure rate in an outpatient setting was 4.3% (95% CI 2.6%-6.3%). Localization of diverticulitis is not a selection criterion for an outpatient strategy (p 0.512). The other subgroup analyses did not report any factors that influence the rate of failure: previous episodes of acute diverticulitis (p = 0.163), comorbidities (p = 0.187), pericolic air (p = 0.653), intra-abdominal abscess (p = 0.326), treatment according to a registered protocol (p = 0.078), type of follow-up (p = 0.700), type of antibiotic treatment (p = 0.647) or diabetes (p = 0.610). In patients who failed outpatient treatment, the majority had prolonged antibiotic therapy and only few had percutaneous drainage for an abscess (0.13%) or surgical intervention for perforation (0.06%). These results should be interpreted with some caution because of the low quality of available data. Conclusions: The outpatient management of AD can reduce the rate of emergency hospitalizations. This setting is already part of the common clinical practice of many emergency departments, in which a standardized protocol is followed. The data reported suggest that this management is safe if associated with an accurate selection of patients (40%); but no subgroup analysis demonstrated significant differences between groups (such as comorbidities, previous episode, diabetes). The main limitations of the findings of the present review concern their applicability in common clinical practice as it was impossible to identify strict criteria of failure
Is the outpatient management of acute diverticulitis safe and effective? A systematic review and meta-analysis
Background: In Western countries, the incidence of acute diverticulitis (AD) is increasing. Patients with uncomplicated diverticulitis can undergo a standard antibiotic treatment in an outpatient setting. The aim of this systematic review was to assess the safety and efficacy of the management of acute diverticulitis in an outpatient setting. Methods: A literature search was performed on PubMed, Scopus, Embase, Central and Web of Science up to September 2018. Studies including patients who had outpatient management of uncomplicated acute diverticulitis were considered. We manually checked the reference lists of all included studies to identify any additional studies. Primary outcome was the overall failure rates in the outpatient setting. The failure of outpatient setting was defined as any emergency hospital admission in patients who had outpatient treatment for AD in the previous 60 days. A subgroup analysis of failure was performed in patients with AD of the left colon, with or without comorbidities, with previous episodes of AD, in patients with diabetes, with different severity of AD (pericolic air and abdominal abscess), with or without antibiotic treatment, with ambulatory versus home care unit follow-up, with or without protocol and where outpatient management is a common practice. The secondary outcome was the rate of emergency surgical treatment or percutaneous drainage in patients who failed outpatient treatment. Results: This systematic review included 21 studies including 1781 patients who had outpatient management of AD including 11 prospective, 9 retrospective and only 1 randomized trial. The meta-analysis showed that outpatient management is safe, and the overall failure rate in an outpatient setting was 4.3% (95% CI 2.6%-6.3%). Localization of diverticulitis is not a selection criterion for an outpatient strategy (p 0.512). The other subgroup analyses did not report any factors that influence the rate of failure: previous episodes of acute diverticulitis (p = 0.163), comorbidities (p = 0.187), pericolic air (p = 0.653), intra-abdominal abscess (p = 0.326), treatment according to a registered protocol (p = 0.078), type of follow-up (p = 0.700), type of antibiotic treatment (p = 0.647) or diabetes (p = 0.610). In patients who failed outpatient treatment, the majority had prolonged antibiotic therapy and only few had percutaneous drainage for an abscess (0.13%) or surgical intervention for perforation (0.06%). These results should be interpreted with some caution because of the low quality of available data. Conclusions: The outpatient management of AD can reduce the rate of emergency hospitalizations. This setting is already part of the common clinical practice of many emergency departments, in which a standardized protocol is followed. The data reported suggest that this management is safe if associated with an accurate selection of patients (40%); but no subgroup analysis demonstrated significant differences between groups (such as comorbidities, previous episode, diabetes). The main limitations of the findings of the present review concern their applicability in common clinical practice as it was impossible to identify strict criteria of failure
Extracting structural features of rat sciatic nerve using polarization-sensitive spectral domain optical coherence tomography
We present spectral domain polarization-sensitive optical coherence tomography (SD PS-OCT) imaging of peripheral nerves. Structural and polarization-sensitive OCT imaging of uninjured rat sciatic nerves was evaluated both qualitatively and quantitatively. OCT and its functional extension, PS-OCT, were used to image sciatic nerve structure with clear delineation of the nerve boundaries to muscle and adipose tissues. A long-known optical effect, bands of Fontana, was also observed. Postprocessing analysis of these images provided significant quantitative information, such as epineurium thickness, estimates of extinction coefficient and birefringence of nerve and muscle tissue, frequency of bands of Fontana at different stretch levels of nerve, and change in average birefringence of nerve under stretched condition. We demonstrate that PS-OCT combined with regular-intensity OCT (compared with OCT alone) allows for a clearer determination of the inner and outer boundaries of the epineurium and distinction of nerve and muscle based on their birefringence pattern. PS-OCT measurements on normal nerves show that the technique is promising for studies on peripheral nerve injury. © 2012 Society of Photo-Optical Instrumentation Engineers (SPIE)
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