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The Pt–Rh alloy is currently the most promising material for aerospace engine thruster nozzles. The performance of the alloy is closely related to the Rh content. Pt-40Rh is the most important variant of the Pt–Rh alloy system. In this paper, the crystal structure, equation of state (EOS), elastic properties and thermal properties of the Pt-40Rh alloy were studied using first-principle calculations based on density, functional theory and the quasi-harmonic Debye model. The results showed that the crystalloid volume of Pt-40Rh was strongly influenced by the pressure and temperature. The higher the temperature and reduced pressure, the greater the change in volume. Under zero temperature and zero pressure, the Poisson's ratio and BH/GH of the Pt-40Rh crystal were 0.335 and 2.433, respectively. Meanwhile, the thermal property calculations also revealed that the constant pressure heat capacity (CP) continued to increase with temperature. The constant body heat capacity (CV) gradually tended to the Dulong-Petit limit value (99.768 J·mol−1·K−1) when the temperature was above 600 K, that is while CP continued to increase with the increase in temperature. [ABSTRACT FROM AUTHOR]

Immersion vaccination is dependent on the response of fish mucosa-associated tissues. Herein, javelin goby Synechogobius hasta was immersed with Vibrio vulnificus bacterin to investigate mucosal and humoral immune responses post-vaccination. The results showed that the specific serum antibody titers gradually increased after vaccination and peaked at day 21, while the mucosal antibody titers in the gill, skin, and intestine showed a faster response, with the peak time at days 3, 5, and 7, respectively. For antigen uptake, a rapid and significant enhancement was detected in the mucosa-associated tissues (gill, skin, and intestine) compared with the blood, spleen, kidney, and liver (P < 0.05). Antigen uptake levels in the gills and skin were peaked at 12 h post-immersion and were significantly higher than other tissues (P < 0.05). The histological results showed that the mucous cell numbers in mucosa-associated tissues increased over time, peaked at day 3 post-immunization, and then decreased to the level of the control groups. Additionally, the mucin components in mucosa-associated tissues shifted from neutral mucopolysaccharide to acidic mucopolysaccharide. Integrations of antibody titers, antigen uptake in mucosa-associated tissues, mucous cell number changes, and mucin characteristic changes provided valuable information for research on mucosal immunity in fish. All present findings suggest a major advantage of immersion vaccines to elicit a high level of local immune response, making immersion vaccines an ideal mode of inoculation that induces protective immunity against a variety of pathogens. [ABSTRACT FROM AUTHOR]

Background: Robotic distal gastrectomy (RDG) is a new technique that is rapidly gaining popularity and may help overcome the limitations of laparoscopic distal gastrectomy (LDG); however, its safety and therapeutic efficacy remain controversial. Therefore, this meta-analysis was performed to evaluate the safety and efficacy of RDG.Methods: We searched PubMed, EMBASE, the Cochrane Library, and Web of Science for studies that compared RDG and LDG and were published between the time of database inception and May 2021. We assessed the bias risk of the observational studies using ROBIN-I, and a random effect model was always applied.Results: The meta-analysis included 22 studies involving 5386 patients. Compared with LDG, RDG was associated with longer operating time (Mean Difference [MD] = 43.88, 95% CI = 35.17-52.60), less intraoperative blood loss (MD = - 24.84, 95% CI = - 41.26 to - 8.43), a higher number of retrieved lymph nodes (MD = 2.41, 95% CI = 0.77-4.05), shorter time to first flatus (MD = - 0.09, 95% CI = - 0.15 to - 0.03), shorter postoperative hospital stay (MD = - 0.68, 95% CI = - 1.27 to - 0.08), and lower incidence of pancreatic fistula (OR = 0.23, 95% CI = 0.07-0.79). Mean proximal and distal resection margin distances, time to start liquid and soft diets, and other complications were not significantly different between RDG and LDG groups. However, in the propensity-score-matched meta-analysis, the differences in time to first flatus and postoperative hospital stay between the two groups lost significance.Conclusions: Based on the available evidence, RDG appears feasible and safe, shows better surgical and oncological outcomes than LDG and, comparable postoperative recovery and postoperative complication outcomes. [ABSTRACT FROM AUTHOR]

This study was to evaluate the effect of stocking densities on the nitrogen and phosphorus budgets for a polyculture of the crab Portunus trituberculatus and the Pacific white shrimp Litopenaeus vannamei. The shrimps (initial weight, 0.012 g) were cultured at a density of 45 shrimpm−2, and juvenile crabs (initial weight, 0.024g) were cultured at five densities of 0, 3, 6, 9, and 12 crabs m−2. The treatments were grouped as C0S45, C3S45, C6S45, C9S45, and C12S45, respectively. Water quality parameters, growth of shrimp and crabs, and nitrogen and phosphorus budget were measured. The results indicated that the shrimp performances in polyculture treatments C3S45 and C6S45 were superior to those in the crab-free treatment (C0S45). The crab in treatments C3S45 and C6S45 exhibited a significantly higher final mean weight and carapace width/length than those in treatments C9S45 and C12S45. The final size and survival of crabs had a negative correlation with the increasing crab stocking density. The contents of total phosphorus and total nitrogen and the comprehensive contamination index values were higher in the C9S45 and C12S45 treatments than in the other treatments. The conversion ratios of nitrogen for crab and shrimp growth in treatment C3S45 were significantly higher than those in the crab-free treatment. These findings indicate that polyculturing shrimp with crabs at suitable densities can improve productivity, profitability, nutrient utilization, and the environmental quality. From the 60-day treatments, the optimal culture densities were 3–6 crabs m−2 and 45 shrimps m−2. [ABSTRACT FROM AUTHOR]

Carbohydrate metabolism may play an important role in maintaining cell homeostasis in bivalves. In the present study, the temporal variations in immune and carbohydrate metabolism parameters of Zhikong scallop Chlamys farreri under an acute Vibrio anguillarum challenge were investigated in order to better understand the energetic mechanisms of scallop immune defense. After bacterial challenge, reactive oxygen species, total antioxidant capacity, acid phosphatase activity, and transcripts of peptidoglycan recognition protein and heat-shock protein 70 in the hemolymph of scallops increased substantially within 96 h. By contrast, the significantly increased malondialdehyde content was observed in the serum of challenged scallops. As far as carbohydrate metabolism was concerned, the expression levels of hexokinase, isocitrate dehydrogenase, and N-acetylglucosaminyltransferase VI in hemocytes of challenged scallops were significantly up-regulated within 192 h. At 192 h, the electron transport system budgets were significantly higher, while the glycogen contents were significantly lower in soft tissues of challenged scallops as compared to those of control. Moreover, the significantly increased glucose content concomitant with significantly up-regulated expressions of sodium glucose transporter 1 and glucose-regulated protein 78 was observed in the hemolymph at 24 h after challenge. The above results demonstrated that bacterial challenge could induce acute immune responses and cause oxidative stress in scallops. During the bacterial stress period, scallops utilized glucose via anaerobic glycolysis and aerobic oxidation to meet the overall cost of immune response. Also, scallops might rely upon the metabolic pathways of glycogen degradation and gluconeogenesis to maintain glucose homeostasis in hemolymph. [ABSTRACT FROM AUTHOR]