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Abstract: In this study, the coating process on the copper surface with titanium dioxide (TiO2) has been introduced. The coated surface exhibits extremely high affinity for water and the solid–liquid contact angle decreases nearly to zero by exposing the surface to ultra-violet light. This superhydrophilic characteristic was applied to nucleate boiling heat transfer of water jet impingement on a flat heated plate. By making use of this special heat transfer surface, the nucleate boiling heat transfer and the critical heat flux (CHF) of a bar water jet impingement on a large flat superhydrophilic surface was experimentally investigated. The experimental data were measured in a steady state. The purified water was employed as the working liquid. Three main influencing factors, i.e., subcooling, impact velocity and the surface coating condition, were changed and their effects on the nucleate boiling heat transfer and the CHF were investigated. The empirical correlations were obtained for predicting the CHF of steady boiling for a small round water jet impingement on a large flat superhydrophilic surface. The experimental results show that the CHF on the superhydrophilic surface is about 30% higher than that on conventional copper surface by decreasing the solid–liquid contact angle. [Copyright &y& Elsevier]

Abstract: An experimental investigation was carried out for predicting the critical heat flux (CHF) of convective boiling of saturated liquids for a round jet impinging on the horizontal jet stagnation zone. The model of maximum liquid subfilm thickness based on the Helmholtz instability was used to derive a semi-theoretical equation. The experimental data of four liquids: water, ethanol, R-113 and R-11 were employed to determine the correlation factor. The impact velocity ranged from 0.5m/s to 10m/s and the diameters of the jet nozzle ranged from 3mm to 10mm. A semi-theoretical correlation was proposed for predicting CHF of convective boiling for saturated liquids jet impinging on the stagnation zone in a wide range. [Copyright &y& Elsevier]

In desalinization devices and some heat exchangers making use of low-quality heat energy, both wall temperatures and wall beat fluxes of the heated tubes are generally quite low, hence they can not cause boiling in flooded tube-bundle evaporators with common large tube spacing. However, when the tube spacing is very small, the incipient boiling in restricted spaces can occur and results in higher heat transfer than that of pool boiling at the same heat flux. This paper investigated experimentally the effects of tube spacing, positions of tubes and test pressures on the boiling heat transfer of water in restricted spaces of the compact in-line bundles consisting of smooth horizontal tubes. The experimental results show that the tube spacing and tube position have significant effect on the boiling heat transfer in a compact tube bundle. There is an optimum tube spacing, which provides the largest heat transfer coefficient at the same heat flux. [ABSTRACT FROM AUTHOR]

This study investigated experimentally the enhancement effects by the restricted space comprising the compact smooth and rolled-worked tube bundles for boiling heat transfer of water and salt/water mixtures under various test pressures. The experimental results show that the small tube gaps can greatly enhance boiling heat transfer for the both tube bundles. There is an optimum tube gap that provides a most enhanced heat transfer effect. The tube position in the enhanced tube bundle has not meaningful effect on the boiling heat transfer. The test pressures show a significant influence on the boiling heat transfer in the compact bundle. The boiling heat transfer increases with increasing the test pressure. [ABSTRACT FROM AUTHOR]

Introduction: The clinical utility of glutamine in patients undergoing colorectal cancer (CRC) surgery remains unclear. Therefore, we aimed to investigate the impact of postoperative treatment with glutamine on postoperative outcomes in patients undergoing CRC surgery., Methods: We included patients with CRC undergoing elective surgery between January 2014 and January 2021. Patients were divided into the glutamine and control groups. We retrospectively analyzed postoperative infections complications within 30 days and other outcomes using propensity score matching and performed between-group comparisons., Results: We included 1,004 patients who underwent CRC surgeries; among them, 660 received parenteral glutamine supplementation. After matching, there were 342 patients in each group. The overall incidence of postoperative complications was 14.9 and 36.8% in the glutamine and control groups, respectively, indicating that glutamine significantly reduced the incidence of postoperative complications [ p  < 0.001; risk ratio (RR) 0.41 [95% CI 0.30-0.54]]. Compared with the control group, the glutamine group had a significantly lower postoperative infection complications rate (10.5 vs. 28.9%; p  < 0.001; RR 0.36 [95% CI 0.26-0.52]). Although there was no significant between-group difference in the time to first fluid diet ( p  = 0.052), the time to first defecation ( p  < 0.001), first exhaust ( p  < 0.001), and first solid diet ( p  < 0.001), as well as hospital stay ( p  < 0.001) were significantly shorter in the glutamine group than in the control group. Furthermore, glutamine supplementation significantly reduced the incidence of postoperative intestinal obstruction ( p  = 0.046). Moreover, glutamine supplementation alleviated the decrease in albumin ( p  < 0.001), total protein ( p  < 0.001), and prealbumin levels ( p  < 0.001)., Conclusions: Taken together, postoperative parenteral glutamine supplementation can effectively reduce the incidence of postoperative complications, promote the recovery of intestinal function, and improve albumin levels in patients undergoing CRC surgery., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Tang, Pi, Qiu and Wei.)

Background: In two facilities in Chongqing, this research sought to retrospectively evaluate the effects of perineal wound infection on survival after laparoscopic abdominoperineal resection (LAPR) of rectal cancer., Methods: To obtain clinical information on patients who underwent LAPR between January 2013 and December 2021, we performed a multicenter cohort study. A total of 473 patients were enrolled: 314 in the non-infection group and 159 in the group with perineal infection. The general data, perioperative conditions, and tumor outcomes between groups were analyzed. The infection rates, recurrence rates, and survival rates of the two centers were compared., Results: The age, height, weight, body mass index (BMI), preoperative complications, preoperative treatment, and intraoperative conditions of patients in the LAPR infection group were not statistically different from those in the non-infection group. The percentage of men, typical postoperative hospital stay, length of initial postoperative therapy, and recurrence and metastasis rates were all considerably higher in the infection group than those in the non-infection group. Wound infection was an independent factor affecting tumor recurrence and metastasis after LAPR as well as an independent factor shortening patient survival time according to multivariate analysis. The incidence of wound infection, the rate of recurrence, and the rate of mortality did not vary significantly across sites., Conclusion: Wound infection after LAPR increases the mean postoperative hospital stay, prolongs the time to first postoperative treatment, and decreases the disease-free survival (DFS) and overall survival (OS). Therefore, decreasing the rate of LAPR wound infection is expected to shorten the postoperative hospital stay and prolong the patient DFS and OS. Patients with postoperative infection may require intensive adjuvant therapy., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Huang, Wei, Qiu, Tang and Sun.)

Hypoperfusion is the main cause of anastomotic leakage (AL) following colorectal surgery. The conventional method for evaluating anastomotic perfusion is to observe color change and active bleeding of the resection margin of the intestine and the pulsation of mesenteric vessels. However, the accuracy of this method is low, which may be due to insufficient observation time. A novel surgical procedure that separates the mesentery in advance at the intended transection site can delay the observation of anastomotic perfusion, and can potentially detect more anastomotic sites with insufficient vascular supply and reduce the rate of AL. This study aimed to investigate the effects of a novel surgical procedure on AL following sigmoid colon and rectal cancer surgeries. A total of 343 patients who underwent rectal and sigmoid colon cancer surgeries were included in the study. From August 2021 to June 2022, patients with sigmoid colon or rectal cancer underwent a new surgical procedure of pre-division of the mesentery (PDM) at the intended transection site (PDM group). Patients with colorectal cancer who underwent conventional surgical procedures from August 2018 to July 2021 were categorized as the non-PDM group. Symptomatic AL (SAL) within 30 days and other outcomes were retrospectively analyzed using propensity score matching and compared between the two groups. The incidences of SAL were 1.3% and 11.3% in the PDM and non-PDM groups, respectively. PDM significantly reduced the SAL rate in sigmoid colon and rectal cancer surgeries (P = 0.009). The incidence of total postoperative complications (P < 0.05) was significantly lower in the PDM group than that in the non-PDM group. There were no significant differences between the two groups for operative time (P = 0.662), intraoperative blood loss (P = 0.651), intraoperative blood transfusion (P = 0.316), and intensive care rate (P = 1). The length of postoperative hospital stay (P = 0.010) and first exhaust (P = 0.001) and defecation time (P < 0.05) were shorter in the PDM group than in the non-PDM group. PDM can effectively prevent AL, and this procedure can be safely performed in sigmoid colon and rectal cancer surgeries., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Tang, Pi, Zhang, Qiu and Wei.)

Controllable chemo- and regiodivergent amination reactions of anilines and chlorins are accomplished by employing different oxidants and substrates, constructing aminated chlorin monomers and dimers with high structural diversity. Importantly, besides preferential 20-meso-position, the oxidative amination was also realized at the inactive 10-meso-position by using phenyliodine bis(trifluoroacetate) (PIFA) and gold(III)-based reagents.