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11.
In this paper, we report on the indoor concentrations from a suite of full-scale outdoor tracer-gas point releases conducted in the downtown area of Oklahoma City in 2003. A point release experiment consisted of releases of sulfur hexafluoride (SF6) in multiple buildings and from different outdoor locations. From the measurements, we are able to estimate the concentration variations indoors for a building operating under “typical” operating conditions. The mean indoor spatial coefficients of variation are 30% to 45% from a daytime outdoor release are around 80% during an outdoor evening release. Having estimates of the spatial coefficient of variation provides stakeholders, including first responders, with the likely range of concentrations in the building when little is known about the building characteristics and operating behavior, such as developing urban-scale hazard and consequence analyses. We show differences in indoor measurements at different distances to the release points, floors of the building, and heating, ventilation, and air conditioning system (HVAC) operation. We also show estimates at different time resolutions. The statistics show that in the studied medium to large commercial buildings, spatial differences would result in peak indoor concentrations in certain parts of the buildings that may be substantially higher than the building average. To our knowledge, very few tracer gas measurements have been conducted in buildings of this scope, particularly with measurements on multiple floors and within a floor. The resulting estimates of spatial variability provide a unique opportunity for hazard assessment, and comparison to multi-zone models. 相似文献
12.
Cerebral microbleeds and cognitive decline in a hemodialysis patient: Case report and review of literature
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Lin Li Mark Fisher Wei‐Ling Lau Hamid Moradi Alexander Cheung Gaby Thai Jason Handwerker Kamyar Kalantar‐Zadeh 《Hemodialysis international. International Symposium on Home Hemodialysis》2015,19(3):E1-E7
Cerebral microbleeds (CMBs) are small hemosiderin deposits indicative of prior cerebral microscopic hemorrhage and previously thought to be clinically silent. Recent population‐based cross‐sectional studies and prospective longitudinal cohort studies have revealed association between CMB and cognitive dysfunction. In the general population, CMBs are associated with age, hypertension, and cerebral amyloid angiopathy. In the chronic kidney disease (CKD) population, diminished estimated glomerular filtration rate has been found to be an independent risk factor for CMB, raising the possibility that a uremic milieu may predispose to microbleeds. In the end‐stage renal disease (ESRD) population on hemodialysis, the incidence of microbleeds is significantly higher compared with a control group without history of CKD or stroke. We present an ESRD patient on chronic hemodialysis with a history of gradual cognitive decline and progressive CMBs. Through this case and literature review, we illustrate the need to develop detection and prediction models to treat this frequent development in ESRD patients. 相似文献
13.
Jonas Ort Benedikt Kremer Linda Grüßer Romy Blaumeiser-Debarry Hans Clusmann Mark Coburn Anke Hllig Ute Lindauer 《International journal of molecular sciences》2020,21(23)
Effective pharmacological neuroprotection is one of the most desired aims in modern medicine. We postulated that a combination of two clinically used drugs—nimodipine (L-Type voltage-gated calcium channel blocker) and amiloride (acid-sensing ion channel inhibitor)—might act synergistically in an experimental model of ischaemia, targeting the intracellular rise in calcium as a pathway in neuronal cell death. We used organotypic hippocampal slices of mice pups and a well-established regimen of oxygen-glucose deprivation (OGD) to assess a possible neuroprotective effect. Neither nimodipine (at 10 or 20 µM) alone or in combination with amiloride (at 100 µM) showed any amelioration. Dissolved at 2.0 Vol.% dimethyl-sulfoxide (DMSO), the combination of both components even increased cell damage (p = 0.0001), an effect not observed with amiloride alone. We conclude that neither amiloride nor nimodipine do offer neuroprotection in an in vitro ischaemia model. On a technical note, the use of DMSO should be carefully evaluated in neuroprotective experiments, since it possibly alters cell damage. 相似文献
14.
Thin Film Thermoelectric Metal–Organic Framework with High Seebeck Coefficient and Low Thermal Conductivity
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Yang Chao-Tung Chen Shuo-Tsung Liu Jung-Chun Chan Yu-Wei Chen Chien-Chih Verma Vinod Kumar 《The Journal of supercomputing》2019,75(8):4408-4429
The Journal of Supercomputing - In the last decade, cloud computing has brought enormous changes to people’s lives. Cloud computing gives a client-driven computational model. In this case,... 相似文献
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18.
Jonathan K. Dozier Mark D. Distefano 《International journal of molecular sciences》2015,16(10):25831-25864
The use of proteins as therapeutics has a long history and is becoming ever more common in modern medicine. While the number of protein-based drugs is growing every year, significant problems still remain with their use. Among these problems are rapid degradation and excretion from patients, thus requiring frequent dosing, which in turn increases the chances for an immunological response as well as increasing the cost of therapy. One of the main strategies to alleviate these problems is to link a polyethylene glycol (PEG) group to the protein of interest. This process, called PEGylation, has grown dramatically in recent years resulting in several approved drugs. Installing a single PEG chain at a defined site in a protein is challenging. Recently, there is has been considerable research into various methods for the site-specific PEGylation of proteins. This review seeks to summarize that work and provide background and context for how site-specific PEGylation is performed. After introducing the topic of site-specific PEGylation, recent developments using chemical methods are described. That is followed by a more extensive discussion of bioorthogonal reactions and enzymatic labeling. 相似文献
19.
This work developed a computational methodology to evaluate and compare standard fire exposures such as those outlined in ASTM E119 with real fire exposures and determine the difference in the temperature rise of a rail car floor assembly. The real fire exposures simulated in this work were identified in a review of incidents and consisted of a constantly-fed diesel fuel spill, a localized trash fire, and a gasoline spill simulated from a collision of the railcar with an automobile. These realistic fire exposures were applied to a variety of exemplar rail cars representative of single-level and bi-level passenger cars. These floor assembly models exposed to realistic fires were simulated in Fire Dynamics Simulator (FDS). The thermal exposure at the underside of railcar provided by FDS was coupled with a thermal model in ABAQUS, which provided the evolution of temperature in different components of the floor assembly. The standard scenarios were simulated for 2 hours instead of the typical 30 minutes to identify the appropriate exposure duration in ASTM E119, which can better represent a real fire scenario. The average and maximum temperatures predicted at the unexposed surface for both scenarios were compared with the threshold values given in NFPA 130. 相似文献
20.
Similarities and differences between male and female novice designers on color‐concept associations for warnings,action required,and signs and equipment status messages
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This research examined the male and female novice designers toward color associations for the concepts used for ‘warnings’, ‘action required’, and ‘signs and equipment status’ through a questionnaire‐based study. A total of 178 Hong Kong Chinese final year undergraduate design students (89 males and 89 females) participated in the study. The test used required the participants to indicate their choice of one of nine colors to associations with each of 38 concepts in a color‐concept table, so that any one color could be associated with any one of the concepts. For both male and female groups of novice designers, chi‐square tests revealed a strong color association for each concept tested in this study (P < .05). The results showed males and females agreed on some color‐concept association stereotypes which were therefore gender neutral. The male and female novice designers had the same color associations and similar levels of stereotype strengths for 21 concepts. The nine strongest and therefore most useful color‐concept association stereotypes for both male and female novice designers were: red‐danger, red‐fire, red‐hot, red‐stop, red‐emergency, red‐error, blue‐cold, blue‐male, and green‐exit. However, the male and female novice designers had different color association stereotypes for the standby (green vs. yellow), emergency exit (green vs. red), and toxic (purple vs. black) concepts, and the strengths of the 14 remaining associations for both groups were not at equivalent levels. Overall, it is anticipated that the findings of this study will act as a useful reference for novice designers and other design practitioners to optimize color coding in the design of ‘warnings’, ‘action required’, and ‘signs and equipment status’ messages. 相似文献