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IMPORTANCE: The safety and efficacy of laparoscopic pancreaticoduodenectomy for pancreatic ductal adenocarcinoma remain controversial. OBJECTIVE: To compare laparoscopic and open pancreaticoduodenectomy performed by experienced surgeons in patients with pancreatic ductal adenocarcinoma. DESIGN, SETTING, AND PARTICIPANTS: This was a noninferiority, open-label randomized clinical trial between September 20, 2019 and March 20, 2022, at 10 hospitals in China. A total of 412 adult patients were assessed for eligibility; 200 patients with histologically confirmed or clinically diagnosed pancreatic ductal adenocarcinoma who were eligible to undergo pancreaticoduodenectomy were enrolled. Study recruitment is complete, and follow-up is ongoing. This article reports prespecified early safety results from the trial. INTERVENTIONS: Participants were randomized in a 1:1 ratio to undergo either laparoscopic or open pancreaticoduodenectomy, to be performed by experienced surgeons who had already performed at least 104 laparoscopic pancreaticoduodenectomy operations. MAIN OUTCOMES AND MEASURES: The primary end point is 5-year overall survival, but the data for this end point are not yet mature; thus, secondary short-term outcomes, including operative findings, complications, mortality, and oncological results are reported here. The outcomes were analyzed according to a modified intention-to-treat and per-protocol principle. RESULTS: Among 412 patients for eligibility, 200 patients were enrolled and randomly assigned 1:1 to have laparoscopic pancreaticoduodenectomy or open pancreaticoduodenectomy. The mean (SD) age was 61.3 (9.3) years, and 78 participants (39%) were female. Laparoscopic procedures had longer operative times (median [IQR], 330.0 [287.5-405.0] minutes vs 297.0 [245.0-340.0] minutes; P < .001). Patients in the laparoscopic group lost less blood than those in the open group (median [IQR], 145.0 [100.0-200.0] mL vs 200.0 [100.0-425.0] mL; P = .02). Ninety-day mortality occurred in 2 of 100 patients in the laparoscopic group and 0 of 100 patients in the open group. There was no difference in the rates of complications of the Clavien-Dindo grades III−IV (n = 17 [17.0%] vs n = 23 [23.0%]; P = .29), comprehensive complication index (median [IQR], 0.0 [0.0-22.6] vs 8.7 [0.0-26.2]; P = .79) or median (IQR) postoperative length of stay (14.0 [11.0-17.0] days vs 14.0 [12.0-18.5] days; P = .37) between the 2 groups. CONCLUSIONS AND RELEVANCE: Laparoscopic pancreaticoduodenectomy performed by experienced surgeons in high-volume specialized institutions resulted in similar short-term outcomes compared with open pancreaticoduodenectomy among patients with pancreatic ductal adenocarcinoma. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03785743

In this work, we investigated the epitaxial growth of (010) β-Ga2O3and β-(AlxGa1–x)2O3films using metalorganic chemical vapor deposition (MOCVD) with trimethylgallium (TMGa) as the precursor, aiming for high growth rates for thick films. We observed pyramid-shaped defects in the β-Ga2O3epitaxial films, characterized by polygon-shaped bumps and inverted pyramids embedded in the epi-films. To improve the surface morphology and suppress the defects formation, we developed a novel approach that incorporates a small amount of aluminum (Al) during the growth process. This addition led to significant improvements in surface morphology and reductions in both the density and size of defects for the low-Al β-(AlxGa1–x)2O3films, with a growth rate of 5.5 μm/h. Our findings demonstrate the effectiveness of this approach in optimizing the surface morphology of thick β-(AlxGa1–x)2O3films with rapid growth rates. We achieved the best surface for β-(AlxGa1–x)2O3in an 11 μm-thick film with approximately 2% Al composition, grown at a rate of 5.5 μm/h. However, we also observed that defect density and size increase with film thickness. Room temperature Hall measurements were used to characterize the electrical properties of the low-Al β-(AlxGa1–x)2O3films, which revealed a decrease in Si incorporation efficiency and room temperature mobility with increasing Al composition. Results indicated that increasing the chamber pressure led to a decrease in both growth rate and Al composition at a constant [TMAl]/[TMGa + TMAl] molar flow rate ratio. The β-(AlxGa1–x)2O3films (∼11 μm) with optimal surface quality were grown at chamber pressures between 60 and 100 torr. This work demonstrates the feasibility of growing (010) low-Al β-(AlxGa1–x)2O3thick films with high growth rates and minimal surface defects using MOCVD. Our findings provide valuable insights into β-(Al)GaO growth and suggest that introducing Al is an effective strategy for improving the surface morphology of β-(Al)GaO films. These results have important implications for the development of high-performance (Al)GaO-based vertical power devices.

Distance measures have been scorching issues in solving problems of multi-attribute decision making (MADM). Though kinds of pioneered distance measures of hesitant fuzzy sets (HFS) have been proposed, several existing ones are still risking in achieving reasonable ranking results as which mainly are constructed on processes of arrangement and extension through adding certain membership degrees. Furthermore, in most distance measures, there are no influences of membership values as hesitant characteristics, which only take lengths of HFS elements (HFEs) into account. From such perspective, we establish the concept of hesitant index to express such hesitance with direction-senses, including positive hesitant index and negative hesitant index. Hesitant index is more supple and applicable in describing hesitant situation towards alternatives containing influences of both different directions of hesitance. Via utilizing positive hesitant index and negative hesitant index, we propose virous distance measures to make up inadequacies of some existing distance measures from the view of combing direct and indirect calculations. Furthermore, on the foundation of hesitant index, hesitant information scale is elaborated to describe characteristics of HFEs. Via taking hesitant information scales as important parts, new distance measures are presented from the view of indirect calculation. Proposed distance measures prompted from hesitant index satisfy better triangle inequality than compared existing ones, and proposed distance measures prompted from hesitant information scales not only satisfy triangle inequality, but also can avoid arrangement and extension processes towards different lengths of HFEs. Finally, relevant experiments demonstrate effectiveness and advantages of proposed distance measures in MADM.

The hesitant fuzzy set has been an important tool to address problems of decision making. There are several various improved hesitant fuzzy sets, such as dual hesitant fuzzy set, hesitant interval-valued fuzzy set, and intuitionistic hesitant fuzzy set, however, no one kind of improved fuzzy sets could reflect attitude characteristics of decision makers on time-sequences. In reality, time-sequence is one important sector to reflect hesitant situations as decision makers might have different knowledges of the same alternative at different moments. To perfect the description of such hesitant situations and obtain more reasonable results of decision making, we define a new kind of hesitant fuzzy set, namely, time-sequential hesitant fuzzy set. Meanwhile, its corresponding basic operators, score function and distance measures are proposed. We also propose the concept of fluctuated hesitant information to describe hesitant degrees of decision makers on time-sequences. By comprehensively utilizing the score function, fluctuated hesitant information and distance measures under time-sequential hesitant fuzzy set, a synthetic decision model is proposed. Two illustrated examples and one real-application are utilized to illustrate the effectiveness and advantage of the synthetic decision model under time-sequential hesitant fuzzy set.

In order to enhance the service life of special complex shaped workpieces under severe working conditions, a new coating preparation process, namely, easy-coating and sintering technology, has been proposed. In this study, the feasibility of preparing Co-based coatings on 38CrMoAl substrates using the easy-coating and sintering process was investigated, and the microstructure and properties of the Co-based coatings were studied. By optimizing the parameters of the sintering process, the prepared coating is dense, and the coating forms a good metallurgical bond with the substrate with few pores, but no other defects. As the process has good applicability to the surface of complex-shaped parts, the inner wall of small serpentine tubes and large thicknesses, and is low-cost and easy to operate, the easy-coating-sintering process has great application prospects.

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.

In this study, we comprehensively investigated the growth of β-Ga2O3on (001) on-axis Ga2O3substrates via metalorganic chemical vapor deposition (MOCVD) using both triethylgallium (TEGa) and trimethylgallium (TMGa) as the Ga precursors. For MOCVD growth with TEGa, the group VI/III molar ratio was tuned with different TEGa molar flow rates. The correlation between growth conditions and the surface morphology, growth rate, and electron transport properties of MOCVD-grown (001) β-Ga2O3thin films is comprehensively analyzed. Room temperature mobility of 85 cm2/V s with carrier concentration of 2.0 × 1017cm–3was measured for a film grown using the TEGa molar flow rate of 19 μmol/min and VI/III molar ratio of 934. For MOCVD growth of (001) Ga2O3using TMGa, we observed the occurrence of cracking along the [010] direction in the grown films, which was found to be closely related to the film thickness and growth rate. The relatively smooth surface morphology of the films with cracks is attributed to the strain relaxation. (001) β-Ga2O3films containing rotation domains with (−401) plane were observed from high-resolution X-ray diffraction (XRD) and confirmed with atomic-resolution scanning transmission electron microscopy (STEM) imaging. Under the same growth condition, (001) β-Ga2O3films contain higher carbon concentration as compared to that of the (010) β-Ga2O3films. Results from this work provide fundamental insights into the MOCVD epitaxy of β-Ga2O3on (001) Ga2O3substrates, revealing the opportunities and challenges of MOCVD growth of (001) β-Ga2O3thin films with fast growth rates for high-power electronic device technology.

Abstract: In this work, we systematically investigate the effects of growth parameters on the structural and surface morphological properties of β-(AlxGa1−x)2O3thin films grown on (010) β-Ga2O3substrates via metalorganic chemical vapor deposition (MOCVD). By varying [TMAl]/[TEGa + TMAl] molar flow rate ratio, growth temperature and chamber pressure, (i) the structural and physical properties of β-(AlxGa1−x)2O3films including Al incorporations, growth rates, strain properties, rocking curve full width at half maximum, and (ii) the surface morphological properties are investigated. Higher [TMAl]/[TEGa + TMAl] molar flow ratio leads to higher Al incorporation in β-(AlxGa1−x)2O3films. Higher growth temperature promotes lower growth rates with substantial surface roughening, although the Al incorporation remains similar for a given [TMAl]/[TEGa + TMAl] molar flow ratio. In addition, increasing chamber pressure leads to lower growth rates and lower Al incorporation in the AlGaO films. This study reveals that the MOCVD growth window for (010) β-(AlxGa1−x)2O3films becomes narrower as the Al composition increases. Graphic abstract:

Aimed at locating the temperature abnormal event of nuclear waste drums in a nuclear waste temporary storage repository by a Raman-based distributed temperature sensor, a principal component analysis (PCA)-based method for application is proposed. The effectiveness of the proposed method is verified in the physical simulation device of the nuclear waste drums. First, some samples of the temperature abnormal event with known location are taken as the reference samples, and their features are extracted by PCA. Then, the features of the test sample data to be located are also extracted by PCA. The Euclidean distance is used to measure the similarity between the features of the test sample and the feature of each reference sample. Finally, we find the reference sample that is most similar to a test sample, the location of which is considered the location of the temperature anomaly event for the test sample. The experimental results show that the proposed method can accurately locate the temperature abnormal event of the nuclear waste drums, and the accuracy rate can reach 96%. The method that is proposed in this paper can reliably locate the temperature abnormal event generated by the nuclear waste temporary storage repository induced by external factors such as landslides or earthquakes, and provide technical support for nuclear safety.

Modified multimodal (MMP) Cr3C2–NiCr coatings were fabricated by high-velocity oxy-fuel (HVOF) spraying deposited on a CuCrZr alloy substrate. However, due to the lack of its inevitable porosity, an additional laser re-melting (LRM) approach is highly required to improve the coating performance. Therefore, the LRM technique is employed in this study to improve the microstructure properties of an MMP Cr3C2–NiCr coating by HVOF. Solid-state phase transformation from Cr3C2to Cr7C3occurred during the LRM process. After the LRM process, the coating exhibits the presence of Cr3C2nanoparticles that serve as reinforcement. These nanoparticles demonstrate minimal lattice misfit and exhibit high stability throughout the LRM process. The surface of the coating undergoes modification, resulting in the formation of homogeneous nano (20–130 nm), micron (150 nm to 0.3 μm), and submicron (2–3 μm) Cr3C2structures, along with high-density microstructures, after the LRM process. Nano-Cr3C2particle reinforced with high total work function and incredibly increased corrosion rate significantly improves coating corrosion resistance. Overall, porosity decreased from 3.9% of the HVOF coating to 0.3% of the LRM. As a result, the current density of anticorrosion decreased from 33.7 to 4.35 µA·cm−2, and the Vickers microhardness average values ranged from 1,050 to 1,300 HV0.3, indicating improved microstructure development and related properties.

Objective PD98059 is a potent and selective inhibitor of mitogen-activated protein kinase. Substantial preclinical evidence has shown an anti-tumor effect of curcumin on various solid tumors. This study aimed to investigate whether curcumin synergistically acts with PD98059 in exerting anti-gastric cancer effects.Methods The cell counting kit-8 assay was used to detect cell proliferation of the human gastric cancer MGC-803 cell line. Flow cytometry was performed to detect apoptosis. Western blotting was used to detect phosphatase and tensin homolog (PTEN) and phosphorylated Akt (p-Akt) expression levels. Quantitative reverse transcription-polymerase chain reaction was used to determine microRNA-21 (miR-21).Results A dose of 5 to 40 µM curcumin inhibited proliferation of MGC-803 cells in a dose- and time-dependent manner. A high dose of curcumin strongly inhibited p-Akt protein expression. With increasing curcumin levels, PTEN expression increased and miR-21 levels decreased. These results suggest that curcumin negatively modulated the miR-21/PTEN/Akt pathway. Moreover, after pretreatment with PD98059, cell apoptosis induced by curcumin was significantly increased. Additionally, the inhibitory effects of curcumin on the miR-21/PTEN/Akt pathway were significantly enhanced.Conclusion PD98059 combined with curcumin may be a potential strategy for managing gastric cancer.

In this paper disturbance observer based model predictive control for path following problems of wheeled mobile robots with input disturbances is proposed. A nonlinear disturbance observer is designed to estimate the disturbances, and to compensate the influence of disturbances. Nominal model predictive control scheme with guaranteed asymptotic convergence is adopted to deal with input constraints of wheeled mobile robots. Simulation example shows that the proposed scheme can drive the wheeled mobile robots to follow a given path despite the presence of slowly varying input disturbances.

The anisotropic dielectric functions (DF) of corundum structured m-plane α-(AlxGa1−x)2O3thin films (up to x= 0.76) grown on m-plane sapphire substrate by metalorganic CVD have been investigated. IR and visible–UV spectroscopic ellipsometry yields the DFs, while X-ray diffraction revealed the lattice parameters (a, m, c), showing the samples are almost fully relaxed. Analysis of the IR DFs from 250 to 6000 cm−1by a complex Lorentz oscillator model yields the anisotropic IR active phonons Euand A2uand the shift towards higher wavenumbers with increasing Al content. Analyzing the UV DFs from 0.5 to 6.6 eV we find the change in the dielectric limits ε∞and the shift of the Γ-point transition energies with increasing Al content. This results in anisotropic bowing parameters for α-(AlxGa1−x)2O3of b⊥= 2.1 eV and b∣∣= 1.7 eV.

The battery management system (BMS) is the main safeguard of a battery system for electric propulsion and machine electrification. It is tasked to ensure reliable and safe operation of battery cells connected to provide high currents at high voltage levels. In addition to effectively monitoring all the electrical parameters of a battery pack system, such as the voltage, current, and temperature, the BMS is also used to improve the battery performance with proper safety measures within the system. With growing acceptance of lithium-ion batteries, major industry sectors such as the automotive, renewable energy, manufacturing, construction, and even some in the mining industry have brought forward the mass transition from fossil fuel dependency to electric powered machinery and redefined the world of energy storage. Hence, the functional safety considerations, which are those relating to automatic protection, in battery management for battery pack technologies are particularly important to ensure that the overall electrical system, regardless of whether it is for electric transportation or stationary energy storage, is in accordance with high standards of safety, reliability, and quality. If the system or product fails to meet functional and other safety requirements on account of faulty design or a sequence of failure events, then the environment, people, and property could be endangered. This paper analyzed the details of BMS for electric transportation and large-scale energy storage systems, particularly in areas concerned with hazardous environment. The analysis covers the aspect of functional safety that applies to BMS and is in accordance with the relevant industrial standards. A comprehensive evaluation of the components, architecture, risk reduction techniques, and failure mode analysis applicable to BMS operation was also presented. The article further provided recommendations on safety design and performance optimization in relation to the overall BMS integration.

This study considered the role of coal as China’s basic energy source and examines the development of the coal industry. We focused on the intelligent development of coal mines, and introduced the “Chinese mode” of intelligent mining in underground coal mines, which uses complete sets of technical equipment to propose classification and grading standards. In view of the basic characteristics and technical requirements of intelligent coal mine systems, we established a digital logic model and propose an information entity and knowledge map construction method. This involves an active information push strategy based on a knowledge demand model and an intelligent portfolio modeling and distribution method for collaborative control of coal mines. The top-level architecture of 5G+ intelligent coal mine systems combines intelligent applications such as autonomous intelligent mining, human–machine collaborative rapid tunneling, unmanned auxiliary transportation, closed-loop safety control, lean collaborative operation, and intelligent ecology. Progress in intelligent mining technology was described in terms of a dynamic modified geological model, underground 5G network and positioning technology, intelligent control of the mining height and straightness of the longwall working face, and intelligent mining equipment. The development of intelligent coal mines was analyzed in terms of its imbalances, bottlenecks, and the compatibility of large-scale systems. Implementation ideas for promoting the development of intelligent coal mines were proposed, such as establishing construction standards and technical specifications, implementing classification and grading standards according to mining policy, accelerating key technology research, and building a new management and control model.

In this work, metalorganic chemical vapor deposition (MOCVD) of (010) β-Ga2O3with fast growth rates was investigated using trimethylgallium (TMGa) as the gallium (Ga) precursor. Key growth parameters including precursor/carrier gas flow, growth temperature, chamber pressure, and group VI/III molar flow ratio were systematically mapped. Surface morphology and charge transport properties of the homo-epi (010) β-Ga2O3thin films were probed to correlate with the crystalline quality. The growth rate of (010) β-Ga2O3thin film increases as the TMGa flow rate increases, and high-quality epi-film is achievable with a fast growth rate up to ∼3 μm/h. By tuning the n-type dopant silane flow rate, the net charge carrier concentration was tuned from ∼1016to 1019cm–3. Room-temperature mobility as high as 190 cm2/V·s was measured for a sample grown with a growth rate of 2.95 μm/h and an electron concentration of 1.8 × 1016cm–3. Temperature-dependent Hall measurement revealed a peak mobility value of ∼3400 cm2/V·s at 53 K. The extracted low compensation level of NA∼ 1.5 × 1015cm–3indicates the high purity of the MOCVD growth of the (010) β-Ga2O3film using TMGa as the Ga precursor. Quantitative secondary-ion mass spectroscopy characterization revealed a relatively high C concentration of 7 × 1016cm–3, indicating that C does not serve as a compensator or a donor in MOCVD grown β-Ga2O3. The results from this study demonstrate the feasibility to grow high-quality Ga2O3thin films with fast growth rates, critical for developing high power electronic device technology.