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The circulating cooling water system is widely used in various industrial production fields, and its operating cost largely depends on external factors, such as ambient temperature and working medium flow. Considering the relative elevation of the heat exchanger, this study establishes a total system operation cost analysis and optimization model based on the superstructure method. The model uses ambient dry bulb temperature, ambient wet bulb temperature, and working medium flow as random variables. Water supply temperature is adopted as the decision variable, and the minimum operating cost of the system is used as the objective function. An analysis of the effect of the three random variables on the operation cost shows that the effect of ambient dry bulb temperature on the operation cost is negligible, and the effect of ambient wet bulb temperature and working medium flow on the operation cost is significant. In addition, a control equation of water supply temperature is established to determine the "near optimal" operation, which is based on the correlation among ambient wet bulb temperature, working medium flow, and optimal water supply temperature. Then, the method is applied to a case system. The operating cost of the system is reduced by 22–31% at different times during the sampling day. [ABSTRACT FROM AUTHOR]

Cofilin-1 (CFL1) and Arp3 expression in 46 squamous cell and adenosquamous carcinomas (SC/ASCs) and 80 adenocarcinomas (ACs) were measured by using immunohistochemistry. Positive CFL1 and Arp3 expression were significantly associated with large tumor size, high TNM stage, lymph node metastasis, and decreased overall survival in both SC/ASC and AC patients ( p < .001). Multivariate Cox regression analysis showed that positive CFL1 and Arp3 expression are independent poor-prognostic factors for both SC/ASC and AC patients. Our study suggested that positive CFL1 and Arp3 expression are closely related to tumor progression, metastasis, and poor prognosis of gallbladder cancer. [ABSTRACT FROM AUTHOR]

Background: Twist, a basic helix-loop-helix transcription factor, has been reported to play a key role in the metastatic progression of several types of cancer. Aims: To investigate the expression and clinical significance of Twist, E-cadherin, and N-cadherin in gastrointestinal stromal tumors (GISTs). Methods: The expression of Twist, E-cadherin, and N-cadherin in GISTs was determined by immunohistochemistry, and their relationship with clinicopathological characteristics was analyzed. Results: The positive rates of Twist, E-cadherin, and N-cadherin in GISTs were 66.7 % (52/78), 35.9 % (28/78), and 75.6 % (59/78), respectively. Twist was expressed significantly more in GISTs with distant metastasis or local invasion ( p < 0.05). Although E-cadherin was expressed significantly less in cases of GISTs with distant metastasis ( p < 0.05), expression of N-cadherin did not differ significantly according to clinical and pathological characteristics ( p > 0.05). Expression of Twist was correlated positively with E-cadherin ( rs = −0.253, p = 0.026) and negatively with N-cadherin ( rs = 0.245, p = 0.030). Conclusions: Twist was expressed significantly more and E-cadherin significantly less in GISTs with metastasis, and expression of both was closely related to metastasis of GISTs. [ABSTRACT FROM AUTHOR]

Abstract: Herein, we present a concept of combining host–guest chemistry with block copolymer self-assembly to fabricate an inner cross-linking block copolymer aggregate with photo-responsive switches on the basis of the reversible interaction between azobenzene and β-cyclodextrin, which can serve as a controllable supramolecular container to load and release guest molecules reversibly. The inner cross-link makes the block copolymer aggregates exhibit good stability, and the aggregates can keep their spherical morphologies during photo-irradiation treatment. When the switches are in on-state, cyclodextrins can bind with hydrophobic pyrene molecules; and when the switches are in off-state, pyrene molecules will get away from the cyclodextrins. The photo-controllable switches embedded in the aggregates endow this new supramolecular container with the capability to load and release guest molecules reversibly without structure disruption. It is anticipated that this line of work may open an avenue for fabricating new polymeric containers which can be used for controllable molecular transfer and catalysis. [Copyright &y& Elsevier]

We report herein the self-organization of the polymerizable bolaamphiphile (noted, l-Asp-DA) that contains a diacetylene group and two l-aspartic groups. We found that l-Asp-DA can self-organize into stable fiberlike nanostructures at the mica−water interface. The micellar nanostructures of l-Asp-DA can be polymerized both in the bulk solution and in the film on UV irradiation, and the nanostructures of the l-Asp-DA micelles at the mica−water interface can be maintained after polymerization. The polymerized l-Asp-DA nanostructures can go through blue−red transition upon pH stimuli arising from the transformation of polydiacetylene skeleton. In addition, the concentration (above cmc) of l-Asp-DA has a great effect on the nanostructures. At a concentration of 3.2 × 10−4mol/L, l-Asp-DA can self-organize into stable fiberlike nanostructure at the mica−water interface, while cylindrical nanostructures self-organize at a concentration of 6.0 × 10−4mol/L. This work may provide a new approach for designing and fabricating molecular assemblies with controlled sizes and shapes, leading to the development of novel functional polymer nanostructure materials. [ABSTRACT FROM AUTHOR]

This work aimed to study the bubble distribution in a multiphase pump. A Euler-Euler inhomogeneous two-phase flow model coupled with a discrete particle population balance model (PBM) was used to simulate the whole flow channel of a three-stage gas-liquid two-phase centrifugal pump. Comparison of the computational fluid dynamic (CFD) simulation results with experimental data shows that the model can accurately predict the performance of the pump under various operating conditions. In addition, the liquid phase velocity distribution, gas-phase distribution, and pressure distribution of the second stage impeller at a 0.5 span of blade height under three typical working conditions were compared. Results show that the region with high local gas volume fraction (LGVF) mainly appears on the suction surface (SS) of the blade. With the increase in inlet gas volume fraction (IGVF), vortices and low velocity recirculation regions are generated at the impeller outlet and SS of the blade, the area with high LGVF increases, and gas–liquid separation occurs at the SS of the blade. The liquid phase flows out of the impeller at high velocity along the pressure surface of the blade, and the limited pressurization of fluid mainly happens at the impeller outlet. The average bubble size at the impeller outlet is the smallest while that at the impeller inlet is the largest. Under low IGVF conditions, bubbles tend to break into smaller ones, and the broken bubbles mainly concentrate at the blade pressure surface (PS) and the impeller outlet. Bubbles tend to coalesce into larger ones under high IGVF conditions. With the increase in IGVF, the bubble aggregation zone diffuses from the blade SS to the PS. [ABSTRACT FROM AUTHOR]