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Cavitation happening inside an inclined V-shaped corner is a common and important phenomenon in practical engineering. In the present study, the lattice Boltzmann models coupling velocity and temperature fields are adopted to investigate this complex collapse process. Based on a series of simulations, the fields of density, pressure, velocity and temperature are obtained simultaneously. Overall, the simulation results agree with the experiments, and they prove that the coupled lattice Boltzmann models are effective to study cavitation bubble collapse. It was found that the maximum temperature of bubble collapse increases approximately linearly with the rise of the distance between the single bubble center and the corner. Meanwhile, the velocity of the micro-jet increases and the pressure peak at the corner decreases correspondingly. Moreover, the effect of angle of the V-shaped wall on the collapse process of bubbles is similar to the effect of distance between the single bubble center and the corner. Moreover, with the increase in bubble radius, the maximum temperature of bubble collapse increases proportionally, the starting and ending of the micro-jet are delayed and the pressure peak at the corner becomes larger and also is delayed. In the double bubble collapse, the effect of distance between two bubble centers on the collapse process of bubbles is discussed in detail. Based on the present study, appropriate measures can be proposed to prevent or utilize cavitation in practical engineering. [ABSTRACT FROM AUTHOR]

Thermal comfort in outdoor spaces is of vital importance to human health and well-being, and affects the livability of cities. In a humid-hot region with elevated temperatures, it is difficult to improve the thermal experience of urban residents by changing objective conditions such as the microclimate. This study created a set of experience indices in different dimensions including visual, auditory, and olfactory perceptions and psychological cognitions, to explore the influencing factors and mechanisms of visitor's thermal comfort in an urban park. We found that visual, auditory, and olfactory experience indices and psychological cognition indices were both strongly correlated with thermal comfort (Pearson correlation coefficients were above 0.3). By analyzing a survey data with a structural equation model, we found that Visual, auditory, and olfactory experiences have a complete, mediating effect on thermal comfort. Explicitly, visual, auditory, and olfactory perceptions affect thermal comfort through two mediating variables: thermal sensation and psychological cognitions. In turn, thermal sensation and psychological cognitions have a direct effect on visitor's thermal comfort. Psychological cognitions has the largest direct effect on thermal comfort. Quantitatively, a 1-unit increase in psychological cognitions produces an increase of 0.601 units in thermal comfort. A potential approach is to improve multisensory modalities that affect necessary sensory perception and psychological cognitions of visitors. The findings of this study provide a valuable reference for the planning and design of recreational spaces in humid-hot regions and for the studies of outdoor thermal comfort. [ABSTRACT FROM AUTHOR]

Objective: To explore the effects of oleic acid on the gene and protein expression of adiponectin and its PPARgamma mechanism in 3T3-l1 adipocytes., Method: L1 adipocytes were incubated with different concentration (25, 50, 100, 200, 400 micromol/L) for 24h, and the mRNA expression of adiponectin and PPARgamma was determined by real-time PCR (relative quantity). And then the 3T3-L1 adipocytes were treated for OA at concentration of 100 micromol/L for 24h with/without the affect of PPARgamma inhibitor GW9662, to determine the gene and protein expression of adiponectin. The protein expression changes of adiponectin were detected by immunoblotting., Result: The mRNA expression of adiponectin and PPARgamma increased at the dosages of 25, 50, and 100micromol /L. With the increase of OA, the mRNA expression of adiponectin and PPARgamma decreased in a dose-dependent manner. Incubating with GW9662 and OA, decreases in the mRNA and protein expression of adiponectin were 77% and 78.01% (P < 0.05), compared with the control respectively., Conclusion: OA could increase the gene expression of adiponectin and PPARgamma mRNA in dose-dependent manner in 3T3-L1 adipocytes,which could be specifically blocked by GW9662, OA indues the expression of adiponectin mRNA and protein in 3T3-L1 adipocytes, possibly by a mechanism involving PPARgamma.