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Objective To investigate the clinical application and efficacy of Da Vinci robotic assisted pancreaticoduodenectomy (RPD) in treatment of periampullary carcinoma（PAC）. Methods The clinical data of 8 patients with PAC (5 cases of pancreatic head adenocarcinoma, 2 cases of duodenal adenocarcinoma, and 1 case of adenocarcinoma of the lower bile duct) admitted to Yancheng First Peoples Hospital from December 2021 to June 2023 were retrospectively analyzed. There were 4 males and 4 females, aged (63±10) years，and all of them were treated with RPD. The patients status during and after operation, and at follow-up were observed, with the follow-up time until June 2023. Results Eight patients successfully completed RPD, without any conversion to open surgery. The surgery time was (358±68) min, and the intraoperative blood loss was (240±112) mL. Only one patients received intraoperative allogeneic blood transfusion. All patients had negative pathological margins and achieved R0 resection. The time to gastric tube extraction, time to initial diet intake, time for getting out of bed and postoperative hospital stay of 8 patients were (3.6±1.1), (2.8±0.6), (2.6±0.4) and (20.8±4.2) days, respectively. There was no secondary operation and no perioperative death. Six cases had perioperative complications (some cases complicated with multiple complications), including 4 cases of mild pancreatic leakage, 1 case of biliary leakage, 3 cases of pleural or abdominal effusion,1 case of intestinal retention,and 1 case of gastric obstruction, all of which were cured after symptomatic conservative treatment. All 8 cases received a median follow-up of 10 months, with 2 cases experiencing tumor recurrence and metastasis, and 6 cases without recurrence and metastasis . One case died due to pulmonary embolism,and 7 cases entered the adjuvant chemotherapy procedure after surgery and all survived, with good living conditions. Conclusion RPD is safe and feasible for the treatment of PAC,and can be applied individually and reasonably.However, long-term prognosis evaluation requires large-size, high-quality clinical studies."

The aim of this work is to study the influence of chamfered perforation and chamfering on the heave and pitch motion of a single floating wind power platform with an anti-heave device. Firstly, the hydrodynamic performance of a single floating body with different chamfers, or without perforation, is calculated and analysed. Secondly, the motion of a model without perforation and with 35° chamfered perforation is captured and studied in a towing tank. The results show that when the wave height is large and the period is small, the perforated device has a certain effect. When the wave height and period are small, the pitch suppression effect of chamfered perforation is more obvious than that of non-chamfered perforation. When the period and wave height are large, the heave suppression effect of non-chamfered perforation is better than that of chamfered perforation. In experimental research, the perforated floating body has a certain effect on restraining the heave and pitch of a floating body under most working conditions, and the effect of restraining the pitch is obviously better than that of restraining the heave.

LuTan-1 (LT-1) is a constellation with two full-polarization L-band radar satellites designed by China, and the first satellite was scheduled to be launched in December 2021 and the second one in January 2022. The LT-1 will be operated for deformation monitoring in repeat-pass mode, and for DEM generation in bistatic mode, improving self-sufficiency of SAR data for the field of geology, earthquake, disaster reduction, geomatics, forestry and so on. In this paper, we focused on designing an algorithm for interferometric DEM generation using LT-1 bistatic satellites. The basic principle, main error sources and errors control of the DEM generation algorithm of LT-1 were systematically analyzed. The experiment results demonstrated that: ① The implemented algorithm had rigorous resolution with a theoretic accuracy better than 0.03m for DEM generation. ② The errors in satellite velocity and Doppler centroid had no obvious effect on DEM accuracy and they could be neglected. While the errors in position, baseline, slant range and interferometric phase had a significant effect on DEM accuracy. And the DEM error caused by baseline error was dominated, followed by the slant range error, interferometric phase error and satellite position error. ③ To obtain an expected DEM accuracy of 2m, the baseline error must be strictly controlled and its accuracy shall be 1.0mm or better for Cross-Track and Normal-Direction component, respectively. And the slant range error and interferometric phase error shall be reasonably controlled. The research results were of great significance for accurately grasping the accuracy of LT-1 data products and their errors control, and could provide a scientific auxiliary basis for LT-1 in promoting global SAR technology progress and the generation of high-precision basic geographic data.

Purpose: Pro-relational opportunism (PRO) is of growing concern in today's business environment. The premise of this study is to investigate the issues that remain relatively underexplored in previous research – antecedents of supplier PRO and how supplier PRO affects the trust and commitment of brand firms. Methodology: Three scenario-based experiments were applied to test the hypotheses. In Studies 1a and 1b, we used a 1 × 2 (Study 1a – inter-organizational identification: low versus high; Study 1b – supplier dependence: low versus high) between-subjects design. Participants were asked to evaluate their ethical philosophies after reading the scenarios. We ran a regression analysis to test for the main and interactive effects of inter-organizational identification, supplier dependence, and ethical philosophy on supplier PRO. Study 2 used a 1 × 2 (supplier PRO: PRO acting versus non-PRO acting) between-subjects design. The bootstrapping method using PROCESS was applied to run a mediation analysis. Findings: This study finds that inter-organizational identification, supplier dependence, and managers' ethical philosophy (utilitarianism and relativism) may increase suppliers' PRO behavior. Utilitarianism and relativism positively moderate the effects of inter-organizational identification and supplier dependence on supplier PRO. Supplier PRO has both a direct and negative impact on the brand firm's commitment and an indirect effect mediated by trust. Research implications: This study provides insight into drivers and outcomes of supplier PRO based on the relationships with brand firms. Influences of inter-organizational determinants are dependent on individual factors. This research extends the supply chain opportunism literature beyond the typically dyadic perspective. Practical implications: Brand firms should be cautioned that strong inter-organizational identification may promote supplier PRO. In addition, brand firms should encourage dependent suppliers to find ethical ways to promote alternative attractiveness. In seeking to avoid damage to the trust and commitment of brand firms, suppliers need to establish systems and norms to help managers develop correct ethical philosophies and understand the harm of PRO behavior. Originality/value/contribution: This research may be the first to examine the antecedents of supplier PRO and its boundary conditions in multi-level settings (i.e. inter-organizational and individual levels). Moreover, this study deepens our understanding of opportunism by further developing the consequences of PRO. [ABSTRACT FROM AUTHOR]

The seepage characteristics of clay core walls are crucial for the seepage safety of core rockfill dams, with the permeability coefficient in the unsaturated zone being nonlinear. To accurately determine the unsaturated seepage parameters in clay core rockfill dams, this paper first proposes an enhanced reptile search algorithm (ERSA) by applying three improvement strategies: Arnold's cat chaotic map, nonlinear evolutionary factor, and adaptive Cauchy–Gaussian mutation with variable weight. Then, by integrating the ERSA with the unsaturated seepage finite element method, an inverse modeling approach is developed. This approach is applied to an actual rockfill dam with operational monitoring data to determine the unsaturated seepage parameters of the clay core. Results indicate that the ERSA outperforms the original RSA in test functions, and the calculation results of the seepage parameters determined through inversion are consistent with the monitoring data, showing an overall mean absolute error of 1.086 m. The inverse modeling approach provides a valuable reference for determining unsaturated seepage parameters in similar clay core rockfill dams. [ABSTRACT FROM AUTHOR]