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Many industrial facilities, such as the widely used cooling tower, transfer heat to the atmosphere. The most common cooling media are water and air. The performance of cooling equipment depends upon such factors as flow rate, pressure at the nozzle tip, and the type of nozzle. In this article, round and slot nozzles with air as the cooling medium are studied to verify their cooling effectiveness. The heat transfer characteristics of these nozzles, compared using three different methodologies, are presented. A commercial computational fluid dynamics tool, FLUNET, is employed to model the 3D thermal-fluidic field of each nozzle. A 1D source code is also implemented in FORTRAN to achieve a faster and more reliable solution. Finally, experimental data are used to verify the two computational results. The difference between the results obtained using the FORTRAN code and FLUENT was about 0.07%. The temperatures at the cooling tower exit for the 1D and 3D codes were 431.9°C and 432.2°C (809.4°F and 810°F), respectively. Four sets of experimental data were compared with the numerical results. The maximum temperature difference between the 1D model and the measurements occurred at an inlet temperature of 450°C (842°F) and at a strip thickness of 2.28 mm. The outlet temperature from the 1D model and measurement was, respectively, 290.1°C and 278.5°C (554.2°F and 533.3°F), differing by approximately 4%. The 1D model generates good temperature predictions compared to measurements from a real cooling tower. This result would be very beneficial for industries that require fast temperature information for stable and steady operation, such as steelworks. [ABSTRACT FROM PUBLISHER]

Objectives: The majority of immune cells in the brain are comprised of microglia, which undergo morphological changes when activated to remove damaged neurons and infectious agents from the brain tissue. In this study, we investigated the effects of type 2 diabetes on microglial activation and the subsequent secretion of pro-inflammatory cytokines, such as interferon-gamma (IFN-gamma) and interleukin-1beta (IL-1beta), in the hippocampus using Zucker diabetic fatty (ZDF) rats and Zucker lean control (ZLC) rats at various diabetic stages. Methods: Zucker lean control and Zucker diabetic fatty rats were sacrificed at 12 (early diabetic stage), 20, or 30 weeks of age (chronic diabetic stage), and the hippocampus was obtained via transcardiac perfusion or dissection for immunohistochemistry and western blot analysis, respectively. Results: Zucker diabetic fatty rats demonstrated significantly higher glucose levels at 12 and 30 weeks of age compared to ZLC rats. Microglia immunoreactive to ionized calcium-binding adapter molecule 1 (Iba- 1) had hypertrophied cytoplasm with retracted processes at 30 weeks of age. In contrast, Iba-1- immunoreactive microglia displayed similar morphology in ZDF and ZLC rats at 12 and 20 weeks of age. Similarly, IFN-gamma and IL-1beta protein levels were significantly increased in ZDF rats compared to ZLC rats at 30 weeks of age, but not at 12 and 20 weeks of age. Interleukin-1beta immunoreactivity in the ZDF rats predominantly increased in the dentate gyrus and CA1 region of the hippocampus compared to that of ZLC rats at 30 weeks of age. In addition, IL-1beta immunoreactive structures in ZDF rats at 30 weeks of age were detected near the astrocytes and microglia. Conclusion: These results suggest that chronic diabetes activates microglia and significantly increases pro-inflammatory cytokine levels in the hippocampus. [ABSTRACT FROM AUTHOR]

Objectives: Luteolin, a common flavonoid from many plants, has various pharmacological activities, including a memory-improving effect. In this study, we investigated the effects of luteolin on spatial memory, cell proliferation, and neuroblast differentiation in the hippocampal dentate gyrus in a rat model of scopolamine (SCO)-induced amnesia. Methods: Scopolamine was subcutaneously administered for 28 days via an Alzet minipump (44 mg/ml delivered at 2.5 μl/h) along with a daily intraperitoneal administration of vehicle (saline) 10 mg/kg luteolin or 5 mg/kg galantamine (GAL) (a control drug for acetylcholinesterase (AChE) inhibitor) for 28 days. Results: The administration of SCO significantly decreased the spatial alteration percentage in the Y-maze test compared to that in the vehicle (saline)-treated group. The administration of luteolin or GAL significantly improved the spatial alteration percentage comoared to that in the SCO-treated group. Similarly, the administration of SCO significantly decreased the cell proliferation (Ki67-positive cells) and neuroblast differentiation (doubleocortin-positive cells) in the dentate gyrus. The administration of luteolin or GAL significantly mitigated the SCO-induced reduction of Ki67- and doublecortin-immunoreactive cells in the dentate gyrus. In addition, the administration of luteolin significantly decreased the lipid peroxidation (malondialdehyde (MDA) levels) and increased the brain-derived neurotrophic factor (BDNF) and AChE levels in the hippocampal homogenates compared to the SCO-treated group. Conclusion: These results suggest that the luteolin treatment improves the SCO-induced reduction of cell proliferation and neuroblast differentiation in the dentate gyrus. The mechanism underlying the amelioration of SCO-induced amnesia by luteolin may be associated with the increase in BDNF, acetylcholine, and the decrease in lipid peroxidation. [ABSTRACT FROM AUTHOR]

Objectives: Adenosine monophosphate-activated kinase (AMPK) is an energy-specific sensor within the central nervous system. In this study, we observed AMPK and its phosphorylated form (pAMPK) in the hippocampal CA1 region after 5 minutes of transient forebrain ischemia. In addition, we also investigated the effects of Compound C, an AMPK inhibitor, against ischemic damage in gerbils. Methods: Adenosine monophosphate-activated kinase and pAMPK immunoreactivity was observed in the hippocampal CA1 region at various time points after ischemia and Compound C was intraperitoneally administered to gerbils immediately after reperfusion and the animals were sacrificed at 5 days after ischemia/reperfusion. Results: Adenosine monophosphate-activated kinase immunoreactivity was transiently increased in the hippocampal CA1 region 1-2 days after ischemia/reperfusion, while AMPK immunoreactivity was almost undetectable in the stratum pyramidale of the CA1 region 4-7 days after ischemia/reperfusion. The administration of Compound C caused a dose-dependent decrease in the ischemia-induced hyperactive behavior, the depletion of ATP, and lactate accumulation in the hippocampal CA1 region within 24 hours after ischemia/reperfusion. In addition, the administration of Compound C decreased reactive gliosis (astrocytes and microglia) and increased the number of cresyl violet-positive neurons when compared to the vehicle-treated group at 5 days post-ischemia/reperfusion. Conclusion: These results suggest that AMPK is transiently phosphorylated following forebrain ischemia in the hippocampal CA1 region and inhibition of AMPK has neuroprotective effects against ischemic damage through the reduction of ATP depletion and lactate accumulation in the hippocampal CA1 region. [ABSTRACT FROM AUTHOR]

Given the overly strict requirements for clear headed-bar spacing in ACI 318-08 and the lack of headed bar provisions in CEB-FIB MC 90, two approximately 2/3-scale exterior beam-column connection subassemblies were tested under cyclic lateral loading. The tests primarily explored the effect on their seismic performance of using (a) small clear spacings and (b) multiple layers of headed bars in the beam. Also, previous test data were thoroughly analyzed. It was concluded that the clear bar spacing of approximately 2db or the use of two bar layers may be permitted for headed bars anchored in exterior beam-column joints. [ABSTRACT FROM AUTHOR]

To improve equipment throughput and device yield, plasma processing equipment should be tightly monitored. A cumulative-sum (CUSUM) control chart is used to monitor off-line process qualities. In this study, a V-mask control chart (VCC) is presented for detecting in-situ process variability. This consisted of a modified cumulative-sum and a V-mask-parameterized belief function. The presented control chart was applied to monitor a radio frequency matching of plasma impedance. Experimental data were measured by using a real-time impedance monitoring system. Detection performance was studied either for the fixed or time-varying VCC parameters. Analysis was more detailed by defining several diagnostic parameters. The detection performance of VCC monitor system was very sensitive to the variations in the design parameters. Optimizing the impact of design parameters considerably improved the detection performance of VCC system. In particular, VCC employing time-varying parameters demonstrated improved detection accuracy. The presented technique can be utilized to monitor other in-situ equipment data. [ABSTRACT FROM AUTHOR]