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To investigate the performance of transcritical CO2 quasi-secondary compression cycle with ejector (TCIEJ) for heat pump water heaters, the thermodynamic model of TCIEJ is established based on the pinch point, and TCEX, TCEJ, and TCI are selected as comparisons. The effects of changing high pressure and ambient temperature on the heating COP and compressor exhaust temperature are analyzed, and the influence of cooling water inlet and outlet temperature and vapor injection pressure on TCIEJ is further analyzed. The results show that there are optimal high pressures that make the heating COP of the four heat pump cycles reach the maximum value, of which TCIEJ has the best performance. At an ambient temperature of −15 °C, the maximum heating COP of TCIEJ increased by about 20.5%, 14.9%, and 7.9% compared with TCEX, TCEJ, and TCI. With the increase in ambient temperature, the optimal high pressure continues to increase, and the corresponding maximum heating COP gradually increases. Selecting the geometric mean of high pressure and evaporation pressure as the optimal vapor injection pressure for TCIEJ, the error is small compared to the actual optimal vapor injection pressure. With the increase in ambient temperature and cooling water outlet temperature, the optimal high pressure of TCIEJ continues to increase, and the correlation formula of optimal high pressure is fitted according to the simulation results. [ABSTRACT FROM AUTHOR]

In order to improve the efficiency of the system and promote its application in other industries, the performance of a thermoelectric subcooled CO2 transcritical heat pump system was studied. A simulation model of the system was established using steady-state lumped parameter technology, and the experimental data were compared with the simulation results. The effects of cooling and chilled water flow rate and temperature, subcooling degree, compressor discharge pressure on the coefficient of performance (COP), and heating coefficient of performance (COPh) were analyzed. The results showed that COP/COPh increased with the increase in cooling and chilled water flow rate and chilled water temperature and decreased with the increase in cooling water temperature. The experimental COPh and COP of the system with a thermoelectric subcooler increased by 4.19% and 4.62%, respectively, compared to the system without it. The simulated data was in good agreement with the experimental data, and the error was within 10%, thus verifying the correctness of the model. When the subcooling degree increased to 11 °C, the system simulation results showed that COP/COPh increased by about 40% and 13.3%, respectively. The optimal high pressure was about 8.0 MPa, which corresponded to the maximum COP and COPh of the system of 3.25 and 4.25, respectively. The research results can provide a theoretical basis for future system optimization. [ABSTRACT FROM AUTHOR]

Oil well cement additives applied in high-temperature environments play an increasingly important role in well cementing work. In this study, a ternary copolymer LNS-1 consisting of sodium styrene sulfonate (SSS), maleic acid (MA), and N-vinylcaprolactam (NVCL) was designed and synthesized using potassium persulfate as an initiator via free radical aqueous solution copolymerization, which was then used as a retarder additive for oil well cement under high-temperature conditions. The structure and performance of copolymer LNS-1 was assessed via gel permeation chromatography, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, nuclear magnetic resonance hydrogen spectrum, Thermogravimetric analysis, and scanning electron microscopy analysis. To study the effect of the retarder on cement slurry properties, the performance of the slurry with LNS-1 was tested. The experimental results demonstrate that LNS-1 was successfully synthesized with excellent retarding ability, thermal resistance, and outstanding suspension; thus, the copolymer can serve as an excellent retarder for oil well cement. Through exploration, it is found that the mechanism of the retarder mainly includes adsorption – membrane layer mechanism and chelation – covering mechanism. NVCL exhibits good complexation, adsorption, hydrolysis stability, and thermal stability. It contains three lone pairs of electrons, which allow the NVCL to chelate Ca2+ that in the liquid phase of the cement. The number of calcium ions is therefore reduced in the cement liquid phase, and cement hydration is inhibited to a certain extent, contributing to a longer hydration process. [ABSTRACT FROM AUTHOR]

Background: Our aim was to evaluate the efficacy and safety of inetetamab plus chemotherapy in the first-line treatment of HER2-positive metastatic breast cancer., Methods: A HOPES study was conducted on patients with HER2-positive metastatic breast cancer. Eligible patients were randomly divided into test group and control group at a 2:1 ratio. Among them, patients in test group received inetetamab plus vinorelbine. Concurrently, patients in the control group received vinorelbine. During the trial, safety evaluation was conducted every 4 weeks and efficacy evaluation was conducted every 8 weeks. As assessed by the Response Criteria Evaluation in Solid Tumors (RECIST) 1.0 criteria, the primary endpoint was progression-free survival (PFS) and the secondary endpoints included objective response rate (ORR) and disease control rate (DCR). Safety was estimated according to the National Cancer Institute Common Toxicity Criteria (NCI-CTC) version 2.0. Efficacy and safety of the postoperative recurrent-metastases first-line subgroup in the HOPES registry study of inetetamab was analyzed and compared with previous clinical studies of trastuzumab in the first-line treatment of HER2-positive metastatic breast cancer., Results: In total, we included 315 patients. Among them, 114 patients in the postoperative recurrent-metastases first-line subgroup were assigned to the full analysis set (FAS) (test group, 72; and control group, 42). The test group significantly prolonged median PFS (mPFS) (11.1 vs. 3.3 months of the control group; P<0.0001). ORR and DCR were remarkably higher than the control group (ORR, 61.5% vs. 29.7% with an increase of 31.8%, P=0.0224; DCR, 93.8% vs. 59.4% with an increase of 34.4%, P=0.0003). Efficacy and safety of postoperative recurrent-metastases first-line subgroup in the HOPES study was comparable to previous clinical studies of trastuzumab as first-line treatment of HER2-positive metastatic breast cancer., Conclusions: Inetetamab has shown efficacy and safety equivalent to trastuzumab for patients in the first-line treatment of postoperative recurrence-metastases HER2-positive breast cancer, which confirms its important status and potential as first-line treatment. Inetetamab provides more first-line targeted therapy options for patients with HER2-positive metastatic breast cancer., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://tbcr.amegroups.com/article/view/10.21037/tbcr-21-42/coif). ZJ serves as the Editor-in-Chief of Translational Breast Cancer Research from November 2019 to October 2024. XW serves as an unpaid Editorial Board Member of Translational Breast Cancer Research from December 2020 to November 2022. The other authors have no conflicts of interest to declare., (2022 Translational Breast Cancer Research. All rights reserved.)

Objective: This paper was written to systematically review and meta-analyze the evidence on the efficacy of lanthanum carbonate (LC) and calcium carbonate (CC) and the risk of cardiovascular calcification on hemodialysis (HD) patients., Materials and Methods: The Cochrane library, PubMed, Web of Science, Chinese journal full-text database (CNKI), WANGFANG DATA, and Sino Med were searched between January 1946 and December 2020. The literature with respect to the randomized controlled clinical trial comparing LC and CC in HD patients was selected. The main outcomes include coronary artery calcification score (CACS), cardiovascular events, and serum phosphorus (mmol/L). The statistical program used for meta-analysis was Stata V14.0., Results: Of 388 original titles screened, data was extracted from 9 studies (625 participants). LC can significantly reduce the progression of coronary artery calcification compared to CC (standardized mean deviation (SMD) = -0.59, 95% CI: -0.94 to -0.25, p < 0.01). The LC group had lower serum phosphorus levels (SMD = -1.35, 95% CI: -2.33 to -0.36, p < 0.01), lower serum calcium levels (SMD = -1.03, 95% CI: -1.83 to -0.23, p = 0.012), and lower fibroblast growth factor 23 (FGF-23) level (SMD = -4.80, 95% CI: -7.96 to -1.64, p = 0.003) than the CC group. The Egger regression test of CACS showed no potential publication bias (p = 0.72)., Conclusion: Compared with CC, LC can significantly delay the process of coronary artery calcification, and at the same time reduce patients' serum phosphate, serum calcium, and FGF-23. Therefore, we recommend LC as a phosphorus-lowering drug for HD patients.