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Thermally rectifying materials would have important implications for thermal management, thermal circuits, and the field of phononics in general. Graphene-based nanostructures have very high intrinsic thermal conductance, but they normally display no thermal rectification effects. The present study relates to a thermally rectifying material and, more particularly, to a graphene-based nanomaterial for controlling heat flux and the associated method determining the rectification coefficient. Thermal rectifiers using a graphene-based nanostructure as thermal conductors were designed. Vacancy defects were introduced into one end of the nanostructure to produce an axially non-uniform mass distribution. Modified Monte Carlo methods were used to investigate the effects of defect size and shape, vacancy concentration, and ribbon length on the thermal rectification properties. Anharmonic lattice dynamics calculations were carried out to obtain the frequency-dependent phonon properties. The results indicated that the nanoscale system conducts heat asymmetrically, with a maximum available rectification coefficient of about 70%. Thermal rectification has been achieved, and the difference in temperature dependence of thermal conductivity is responsible for the phenomenon. Defects can be tailored to modulate the temperature dependence of thermal conductivity. The power-law exponent can be negative or positive, depending upon the ribbon length and vacancy concentration. A computational method has been developed, whereby the numerous variables used to determine the rectification coefficient can be summarized by two parameters: the power-law exponent and the thermal resistance ratio. Accordingly, the rectification coefficient can be obtained by solving a simple algebraic expression. There are several structure factors that cause noticeable effects on the thermal rectification properties. Defect size, vacancy concentration, and ribbon length can affect the thermal conductance of the nanostructure symmetrically and significantly. Graphene-based nanostructure thermal rectifiers can be arranged in an array so as to provide thermal rectification on a macroscopic scale., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Background: Synovial sarcoma is a soft tissue sarcoma of temporarily unknown histologic origin with the ability for biphasic differentiation, occurring mostly in the vicinity of large joints of the extremities. Synovial sarcoma that originates in the liver is extremely rare. Only 7 cases have been reported in the domestic and international literature., Case Presentation: We report an 11-year-old female patient who underwent partial hepatectomy for a liver mass. Microscopically, she was diagnosed with hepatic biphasic synovial sarcoma. Cytogenetic examination revealed the fusion gene SS18-SSX1 (+), which confirmed the diagnosis., Conclusion: Synovial sarcoma of the liver is a rare malignancy that is difficult to diagnose. Confirmation of diagnosis is based on histopathological assessment combined with immunohistochemical staining and, if necessary, cytogenetic aids., (© 2022. The Author(s).)

Colorectal cancer (CRC) is the third most common malignant tumor in the world. Previous research has shown that Lacticaseibacillus paracasei strains and its cultures have anti-colon cancer effects, but the study of L. paracasei-derived extracellular vesicles (LpEVs) as intercellular communication molecule against colon cancer has not been previously reported. Our research showed LpEVs were taken in by colorectal cancer cells. Subsequently, LpEVs inhibited the proliferation, migration, invasion and promote apoptosis of colorectal cancer cells. LpEVs inhibited the growth of CRC xenograft in nude mice and promoted tumor apoptosis in vivo. Transcriptome sequencing analysis revealed that differentially expressed genes were involved in the regulation of apoptosis. LpEVs significantly inhibited the phosphorylation level of 3-phosphoinositide-dependent protein kinase-1 (PDK1) and AKT in colorectal cancer cells and reduced the expression of Bcl-2 protein. In conclusion, extracellular vesicles of Lacticaseibacillus paracasei PC-H1 can inhibit the growth of colorectal cancer cells in vivo and vitro and induce apoptosis through PDK1/AKT/Bcl-2 signaling pathway. This research not only provides a new mechanism for the anti-tumor effects of probiotics, but also opens up new opportunity for the treatment of colon cancer., (Copyright © 2021 The Authors. Published by Elsevier GmbH.. All rights reserved.)

Background: The benefit and safety of laparoscopic pancreatoduodenectomy (LPD) for the treatment of pancreatic or periampullary tumours remain controversial. Studies have shown that the learning curve plays an important role in LPD, yet there are no randomised studies on LPD after the surgeons have surmounted the learning curve. The aim of this trial was to compare the outcomes of open pancreatoduodenectomy (OPD) with those of LPD, when performed by experienced surgeons., Methods: In this multicentre, open-label, randomised controlled trial done in 14 Chinese medical centres, we recruited patients aged 18-75 years with a benign, premalignant, or malignant indication for pancreatoduodenectomy. Eligible patients were randomly assigned (1:1) to undergo either LPD or OPD. Randomisation was centralised via a computer-generated system that used a block size of four. The patients and surgeons were unmasked to study group, whereas the data collectors, outcome assessors, and data analysts were masked. LPD and OPD were performed by experienced surgeons who had already done at least 104 LPD operations. The primary outcome was the postoperative length of stay. The criteria for discharge were based on functional recovery, and analyses were done on a modified intention-to-treat basis (ie, including patients who had a pancreatoduodenectomy regardless of whether the operation was the one they were assigned to). This trial is registered with Clinicaltrials.gov, number NCT03138213., Findings: Between May 18, 2018, and Dec 19, 2019, we assessed 762 patients for eligibility, of whom 656 were randomly assigned to either the LPD group (n=328) or the OPD group (n=328). 31 patients in each group were excluded and 80 patients crossed over (33 from LPD to OPD, 47 from OPD to LPD). In the modified intention-to-treat analysis (297 patients in the LPD group and 297 patients in the OPD group), the postoperative length of stay was significantly shorter for patients in the LPD group than for patients in the OPD group (median 15·0 days [95% CI 14·0-16·0] vs 16·0 days [15·0-17·0]; p=0·02). 90-day mortality was similar in both groups (five [2%] of 297 patients in the LPD group vs six [2%] of 297 in the OPD group, risk ratio [RR] 0·83 [95% CI 0·26-2·70]; p=0·76). The incidence rate of serious postoperative morbidities (Clavien-Dindo grade of at least 3) was not significantly different in the two groups (85 [29%] of 297 patients in the LPD group vs 69 [23%] of 297 patients in OPD group, RR 1·23 [95% CI 0·94-1·62]; p=0·13). The comprehensive complication index score was not significantly different between the two groups (median score 8·7 [IQR 0·0-26·2] vs 0·0 [0·0-20·9]; p=0·06)., Interpretation: In highly experienced hands, LPD is a safe and feasible procedure. It was associated with a shorter length of stay and similar short-term morbidity and mortality rates to OPD. Nonetheless, the clinical benefit of LPD compared with OPD was marginal despite extensive procedural expertise. Future research should focus on identifying the populations that will benefit from LPD., Funding: National Natural Science Foundation of China and Tongji Hospital, Huazhong University of Science and Technology, China., Competing Interests: Declaration of interests All authors declare no competing interests., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Hepatic artery variations increase the difficulty of laparoscopic pancreaticoduodenectomy (LPD). The safety and efficacy of LPD in the presence of aberrant hepatic arteries (AHA) must be further verified.Patients with normal and variant hepatic arteries who underwent LPD and preoperative arterial angiography were retrospectively analyzed. Variation type, intraoperative management, and clinical treatment outcomes were compared.There were 54 cases (24.8%) of AHA. The most common hepatic artery variation was accessory right hepatic artery (RHA) from the superior mesenteric artery (SMA, n = 12, 5.5%), followed by replaced RHA from the SMA (n = 10, 4.6%), accessory left hepatic artery from the SMA (n = 10, 4.6%), and replaced common hepatic artery from the SMA (n = 6, 2.8%). Each type of arterial variation was successfully preserved in all cases, and there were no significant effects on the evaluated surgical indices, conversion rate, incidence of postoperative complications, or follow-up results.Our findings indicated that preservation of AHAs during total LPD is feasible. There were no significant effects on surgical indices, incidence of postoperative complications, or follow-up outcomes.The influence of AHA on the safety and efficacy of LPD must be further verified. Patients with normal and variant hepatic arteries who underwent LPD and preoperative arterial angiography were retrospectively analyzed. There were 54 cases (24.8%) of AHA. There were no significant effects of AHAs on surgical indices, incidence of postoperative complications, or follow-up outcomes.

Mixing is an important operation in solid-state anaerobic digestion (SS-AD) to improve the mass transfer of the solid phase. This study proposed simple turning by loader in common garage-type digester without commonly used mixer or percolation system (simplified SS-AD). In simplified-SS-AD, turning is conducted in open condition. Thus, oxidation of anaerobic sludge during turning would influence digestion performance. Therefore, in this study, the effect of turning wastes by mixing during digestion on a simplified SS-AD fed with rice straw and pig urine was investigated. Four different mixing frequency levels-no mixing (M0) and mixing once a day (M-1/1), once every 3 days (M-1/3) and once a week (M-1/7)-were conducted. Methane yields of M0, M-1/3 and M-1/7 were comparable with each other. Methane yield and lag period of M-1/1 were approximately 61% and 155% of M0 (351.2  mL/g VS and 4.7 days), respectively. Furthermore, the chemical oxygen demand (COD) of acetate accumulated in the digestate of M-1/1 was comparable to the difference in the COD of methane production between M-1/1 and the other treatments. Mixing every day also resulted in a higher oxidation-reduction potential and carbon dioxide content. These findings suggest that methanogenesis was inhibited in M-1/1 by frequent mixing in the atmosphere. Net energy analysis of SS-AD plant operation showed that M0 can obtain the highest net energy gain, whereas net energy production of M-1/7 was reduced by rewarming after mixing. Therefore, no mixing is the most effective approach for the proposed simplified process., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

This study investigated the effect of the feedstock-to-inoculum (F/I) ratio on performance of the solid-state anaerobic co-digestion of pig urine and rice straw inoculated with a solid digestate, and clarified the microbial community succession. A 44-day biochemical methane potential test at F/I ratios of 0.5, 1, 2 and 3 at 55 °C and a 35-day large-scale batch test at F/I ratios of 0.5 and 3 at 55 °C were conducted to investigate the effects of F/I ratio on anaerobic digestibility and analyze microbial community succession, respectively. The highest cumulative methane yield was 353.7 m 3 /t VS in the large-scale batch test. Volatile fatty acids did not accumulate at any F/I ratios. The volatile solids reduction rate was highest at a F/I ratio of 0.5. Microbial community structures were similar between F/I ratios of 3 and 0.5, despite differences in digestion performance, suggesting that stable operation can be achieved at these ratios., (Copyright © 2017 Elsevier Ltd. All rights reserved.)