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Ti4Al0.5NiCr2NbTa0.5 non-equimolar high entropy alloy (HEA) coatings were successfully prepared by laser cladding technology, the Ta element alloyed state in the coatings was changed by adjusting the laser energy density during cladding. The effects of Ta alloyed state on the phase structure, microstructure evolution, microhardness, corrosion resistance and passivation film of coatings were investigated. The results showed that the Ti4Al0.5NiCr2NbTa0.5 coating was composed of BCC and Ti2Ni-laves phases. With the increase in energy density, the increased content of Ta in the BCC phase promotes the formation of the BCC phase while suppressing the precipitation of the Ti₂Ni-Laves phase. However, this also leads to the transformation of the BCC phase from a fine dendritic structure to coarse equiaxed crystals. Meanwhile, the Laves phase, which is initially distributed in a reticulated at the grain boundaries, gradually fragments into a dotted distribution within the BCC phase. As grain coarsening occurs and the Laves phase decreases, the effects of fine-grain strengthening and second-phase strengthening gradually weaken, and the microhardness of the coating decreases from 675.5 HV to 483.4 HV. Additionally, the coating exhibited excellent corrosion resistance. With the change in the alloyed state of Ta, the stability of the passive film on the coating gradually increased, and the oxides of the refractory elements Ta and Nb transitioned from a sub-oxidized state to a stable oxidized state. The minimum corrosion current density of the coatings was only 0.877 × 10−8 A/cm2, and secondary passivation were observed during the polarization treatment of all coatings.

To address the need for weight reduction in a large unmanned aerial vehicle (UAV) fuselage, this study focused on the load-bearing joint structure manufactured through selective laser melting (SLM). A finite element model of this structure was created and analyzed using ANSYS Workbench to evaluate its strength and stiffness under various extreme conditions. The design was verified against the material’s maximum permissible stress criterion. The study then employed topology optimization, using the variable density method aimed at minimizing stress, to optimize the joint structure while retaining 40% of its original mass. Based on the optimization results, two redesign schemes were developed and validated through static analysis. In the optimized models, significant material removal was observed in the middle part of the thin plate connected by the covers of Scheme I and Scheme II. The latter, in particular, demonstrated the largest side length of material removal at 56 mm. The weights of Scheme I and Scheme II were reduced to 0.325 kg and 0.327 kg, respectively, down from the initial mass of 0.377 kg, translating to weight reductions of 13.8% and 13.3%, respectively. The results indicated that Scheme II achieved a notable 13.3% weight reduction while maintaining the strongest load-bearing capacity among the alternatives. Under similar loading conditions, Scheme II exhibited lower stress concentration compared to Scheme I, with reductions of 21.6%, 5.0%, 20.6%, and 27.8% from working condition 1 to working condition 4, respectively. The “wide and short” aperture at the connecting plate helped disperse stress, enhancing load-bearing capacity while compromising on weight reduction. Additionally, Scheme II showed minimal deformation, with a minimum deformation of 0.16 mm, indicating higher stiffness and better resistance to deformation. This indicates that Scheme II is more efficient in maintaining structural integrity under load, making it a more viable option for the UAV fuselage’s load-bearing joint structure. This study demonstrates combining topology optimization with SLM can greatly shorten the manufacturing cycle and produce complex structural parts efficiently. This approach provides important theoretical guidance and reference for the lightweight design and manufacturing field of large-scale UAV load-bearing joint structures. The integration of these advanced techniques advances performance optimization and production efficiency in large-scale UAV load-bearing joint structures. Moreover, it promotes the innovation and development of aerospace manufacturing technology by enabling the creation of more efficient, lighter, and stronger components. Overall, the findings highlight the potential for significant advancements in UAV design and manufacturing, offering practical insights and methodologies applicable to similar engineering challenges in the aerospace industry. The research underscores the importance of adopting cutting-edge technologies such as SLM and topology optimization to achieve superior performance in aerospace applications.

Invar alloys are frequently utilized in the production of composite molds, owing to their excellent dimensional stability and closely matched coefficient of thermal expansion to that of the composite materials. The inherent wear resistance of Invar alloys is limited, which significantly impacts their overall service life. Therefore, in this study, Invar-WC coating and laser remelting coating were prepared on the surface of Invar alloy by laser cladding technology. The microstructures and phase compositions of the different coatings were analyzed, and the hardness and wear resistance of the two coatings were tested and observed in the wear micro-morphology. The results show that the two coatings are well formed. The main phase composition of Invar-WC coating is Fe0.64Ni0.36, and the reinforcing phases such as W2C、M7C3, were formed in the substrate under the effect of W and C elements. The wear resistance of the remelted coating was increased by 63.55% over the substrate, and the wear resistance of the Invar-WC coating was further increased by 97.69% over the substrate. The Invar-WC coating was strengthened by fine grain reinforcement and the second phase reinforcement under the action of WC particles, which led to the increase of the hardness of the Invar-WC coating, and the enhancement of the wear-resistant property. Meanwhile, the wear mechanism of the substrate and laser remelting is characterized by adhesive wear, while the wear mechanism of the Invar-WC coating is characterized by abrasive wear due to the presence of WC particles, resulting in a significant increase in wear resistance.

A reusable reentry vehicle requires a thermal protection structure with high strength and heat resistance for repeated traveling between the Earth and space. In this study, various transition modes of TiC/Ti6Al4V graded materials were designed and fabricated by direct energy deposition, and then ablation tests were conducted to simulate the service environment. The influence of microstructure morphology on the heat resistance of the graded materials was revealed by analyzing the changes in the internal microstructure, element distribution, and microcrack. Compared with Ti6Al4V titanium alloy, TiC/Ti6Al4V graded materials show almost no mass loss or ablation pits, indicating a significant improvement in heat resistance. The Ti6Al4V titanium alloy exhibited macroscopic cracks up to 700 μm in length on the surface after the ablation test; as a contrast, the surface area of the TiC/Ti6Al4V graded materials exhibited fine microcracks, and there were no significant changes in the internal structure. The improvement in the heat resistance of TiC/Ti6Al4V graded materials is attributed to the combined effects of the interface heat resistance between the TiC and Ti6Al4V and the change of heat conduction path within the matrix.

The present study examined the evolution of interfacial microstructure and on the element distribution of GH4169/GH3039 dissimilar joints by laser welding under different preheating temperatures. The results indicated that the microstructure observed in the interface layer on the GH4169 side exhibited distinct layers, namely diffusion layer and transition layer, which varied depending on the varied preheating temperature. Within the weld seam (WS), two types of dendrites were predominantly present: lath-like columnar dendrite and cellular dendrite. In the GH3039 side, the grain structure was mainly dominated by columnar dendrites, exhibits perpendicular growth to the fusion line and demonstrates a certain epitaxial growth morphology. Moreover, excessive preheating temperature intensified the migration of elements and phase transition behavior. As the preheating temperature increased, the low-angle grain boundaries (LAGBs) percentage decreased from 13% to 9.4%. The average grain size of the WS at room temperature, 200 °C and 400 °C is 44.1 μm, 53.3 μm and 58.2 μm, respectively. This paper provides a basis for tuning microstructure and element behavior via preheating temperature optimization in laser welding of dissimilar GH4169/GH3039 for further engineering application.

Controlling repeated thermal cycling is one of the key mechanisms to design microstructures in the interlayer regions for narrow gap laser wire filling welding (NGLWFW) of austenite stainless steels. Herein, the optimization of process parameters for individual layers is tailored to customize the molten pool morphology during the NGLWFW process, facilitating precise control over the microstructure and, consequently, enhancing both mechanical properties and corrosion resistance of the joint. The results showed that the molten pool morphology acquired by simulation are obviously diverse from the bottom zone (BZ), middle zone (MZ) to upper zone (UZ) of the welded joint ascribed to the high heat accumulation effect, leading to the variation of microstructure. At BZ, the combination of smaller grain size and reduced dendrite spacing reduce the number of corrosion sites and promote the formation of a denser and more uniform corrosion product layer. Additionally, the diverse grain orientation, characterized by lower texture strength, facilitated a more uniform distribution of elements. Furthermore, the significantly higher content of δ-ferrite showing smallish shape disrupted the directional growth of austenite columnar grains, contributing to the excellent corrosion resistance observed at the BZ.

The laser welding of dissimilar 2219 Al–Cu and 2195 Al–Li alloys is a significant attempt in the fabrication of rocket propellant tanks, aiming at the escalating demands for weight reduction and cost efficiency. The variances in microstructure evolution for 2219/2195 aluminum alloys laser welded joint deserves thorough investigation because it certainly results in the discrepancies in mechanical property In this paper, the temperature field, microstructure, element distribution, grain orientation, and texture on both sides of the laser welded joint were comprehensively investigated through a combination of simulations and experiments. The tensile strength was tested and the fracture mechanism was analyzed based on the microstructure characteristic. It is found that the wider columnar dendrites zone is generated due to the large temperature gradient from on the 2195 Al–Li alloy side. The grain orientation of the non-dendrite equiaxed zone (EQZ) and columnar grain near the fusion line are significantly influenced by the grain orientation of base metal (BM). On the one side of 2195 Al–Li alloy, the majority of grains feature diameters predominantly within the 3–6 μm range. The region in the vicinity of fusion line on one side of the 2195 Al–Li alloy has the weakest performance. It is deduced that the poor tensile property on one side of the 2195 Al–Li alloy is not only attributed to the loss of Mg and Li elements, but also owing to the evolution of texture. The rotated goss texture with high intensity is formed in EQZ near the fusion line on one side of 2219 Al–Cu alloy.

The diagnosis and treatment of head and neck undifferentiated carcinoma (HNUC) present significant challenges. Herein, we present the case of a patient with advanced HNUC who underwent conversion surgery following treatment with a combination of pembrolizumab and nimotuzumab. During therapy, histological transformation from undifferentiated to sarcomatoid carcinoma was detected at the primary site. This case not only highlights the potential of immune combination-targeted therapy to reduce tumour burden and increase the surgical options for patients, but also reveals the complex alterations in tumour biology that may occur during treatment. It emphasizes the necessity for routine pathological assessments throughout the therapeutic regimen to guide personalised therapeutic strategies and optimise patient prognoses.

Abstract Background Breast cancer is the most common malignant tumor among women worldwide. GREB1L is a protein-coding gene. Previous studies have shown that GREB1L plays a vital role in lung and gastric adenocarcinoma. Currently, there is no relevant report about its role in breast cancer. Methods The Cancer Genome Atlas database was used to compare the expression level of GREB1L between tumor and normal tissues. The TISIDB website was used for prognosis analysis. The LinkedOmics database was used to predict the potential biological mechanism of GREB1L in breast cancer. Immunohistochemistry was used to detect the GREB1L expression level in breast tissue. Western blotting was used to detect the GREB1L expression level in cell lines. Transwell assays, CCK-8 cell proliferation assays, and colony formation assays were used to detect the migration, invasion, proliferation, and colony formation abilities of cells. Subcutaneous xenograft models were used to detect the in vivo tumor formation abilities of cells. Results GREB1L is highly expressed in breast cancer tissues and breast cancer cells. KEGG enrichment analysis suggested that GREB1L participates in the regulation of the Hedgehog signaling pathway; changes in GREB1L expression affected the migration and invasion abilities of MCF7 and MDA-MB-231 cells. Although changes in GREB1L expression did not affect their proliferation and colony formation abilities in vitro and in vivo, they affected the expression of tumor metastasis-related genes in vivo. The overexpression of GREB1L in breast cancer predicted a favorable prognosis. Conclusion These results showed that GREB1L is involved in the development of breast cancer, and it may be a potential molecular marker for predicting the prognosis of breast cancer.

Laser melting deposition (LMD) is an additive manufacturing technology that involves complex thermodynamic and kinetic characteristics in the molten pool. A perspective on the thermal-fluid dynamic behavior in the molten pool is essential for investigating the microstructure morphology and solidification characterization. In this study, a three-dimensional transient thermal-fluid coupling model is proposed for describing thermal-fluid dynamic behavior within the molten pool during laser melting deposition of TiC/Ti6Al4V functionally graded materials. The simulated temperature distribution and deposition layer morphology agree well with the experimental results. The simulation results indicate that the heat accumulation phenomenon generated during the LMD process can exacerbate the penetration effect of the molten pool. The solidified deposition layer will be remelted to form a large cross-layer molten pool, and the molten metal in the remelted zone will move from the lower layer to the upper layer driven by the Marangoni convection. Furthermore, the unmelted TiC particles and the in-situ generated TiC particles can decrease the free energy of the molten pool, induce heterogeneous nucleation, and promote the growth of equiaxed crystals.

Laser cladding provides a cost-effective and high-quality solution for repairing aircraft engines. A finite element model was developed in this study to simulate and analyze the stress distribution during the cladding of a complex curved groove structure made of Ti6Al4V. The mechanism underlying the microstructure at the interface was revealed. The stress concentration locations in the curved groove structure are located at the intersection of the cladding layer and sidewall, as well as at both ends of the cladding layer and the groove bottom. By applying reverse swing scanning, a more consistent distribution of stress fields can be obtained. Optimizing the scanning strategy reduced the maximum stress in the repair layer from 717 MPa to 711 MPa. The experimental stress distribution data are in good agreement with the computational results. The cladding layer undergoes changes in heat cycling and nucleation conditions, leading to the formation of alternating columnar and equiaxed grain morphologies.

ABSTRACTInhibiting unhomogenised microstructure during the directed energy deposition process with the electric arc energy source (DED-Arc) has become a significant challenge. Ultrasonic vibration leads to the severe stirring of liquid metal and break down dendrites in the inner-layer zone, which promotes the formation of fine grains after rapid solidification. In contrast, the grain refinement effect is not obvious in the semi-melting zone. The addition of ZrO2 particles in the 2319 Al-Cu alloy during the DED-Arc process can drag and pin the grain boundary to prevent grain coarsening in the semi-melting zone. Under the integrated effect of ultrasound and particles, ZrO2 particles can be evenly distributed in different regions, which is beneficial to enhance the microstructure uniformity of the deposition layer and ultimately achieving significant improvement in mechanical properties. The intergrated effect of ultrasonic vibration and particles on strength and elongation reach 13.8% and 92.4%, respectively.

In order to improve the performance of welded joints in Al-Li alloys, butt joints consisting of 2 mm thick 2195-T8 Al-Li alloy plates are fabricated by laser beam welding with different filler wires in this paper. The joints welded by ER2319CT, ER4047, and without filler are investigated in the context of microstructure, the distribution of alloying elements, the burning loss of alloying elements, and tensile strength. From the fusion boundary to the center of the weld seam (WS), the crystal morphologies vary in the sequence of fine equiaxed grains, columnar dendrite, and equiaxed dendrite. The equiaxed grains and columnar dendrite disappear in certain areas of the WS by ER2319CT. The burning loss rates of Li and Cu in the WS by filler wires are higher than those by laser welding without filler. AlLiSi and Al2Cu are identified as the strengthening phases in the WS by ER4047, while Al2Cu, Al2CuLi, and Al6CuLi3 are the strengthening phases in the WS by ER2319CT. Compared with laser welding without filler wire, more strengthening phases improve the mechanical properties of the welded joints by filler wires. Both types of welding wires can improve the performance of welded joints, and ER2319CT is more effective.

High-entropy alloy (HEA) coatings on the surface of low-alloy steel by laser cladding can improve the corrosion and wear resistance, and the performance can be further improved by adding the Cr element. However, the effect of Cr content on the microstructure, hardness, wear and corrosion resistance of the coatings on the welded joint has not been completely understood in the literature. This paper aims at revealing the influence of Cr content on the microstructure and properties of laser-cladded FeCoCrxNiAl HEA on different regions of Q345 welded structure. The results indicate that FeCoCrxNiAl HEA coating has good metallurgical bonding with the Q345 welded surface. The increase of Cr element content in the powder plays an important role in energy absorption of powder and substrate, affecting the dilution rate and diffusion of Fe from the substrate to HEA coating. The HEA coating is mainly composed of the face-centered cubic phase (FCC) and body-centered cubic phase (BCC). When x = 1.5, the actual Cr element content of coating is the highest, which promotes the formation of hard brittle phase BCC, and subsequently affects the hardness and wear resistance of the sample. Meanwhile, the corrosion resistance increases and then decreases, and reaches the highest when x = 1.5. Due to the existence of Cr and other elements with good corrosion resistance in the HEA coating, a dense oxide film can be formed in 3.5 wt.% NaCl solution and neutral salt spray environment to prevent the corrosion from continuing, which can effectively improve the corrosion resistance of each region of the welded joint, and the protective efficiencies on the weld bead (WB), heat-affected zone (HAZ) and base metal (BM) are 99.1, 98.4 and 96.6%, respectively.

The quality of a laser deep penetration welding joint is closely related to porosity. However, the keyhole stability seriously affects the formation of porosity during the laser welding process. In this paper, a three-dimensional laser welding model with gas/liquid interface evolution characteristics is constructed based on the hydrodynamic interaction between the keyhole and molten pool during the laser welding process. The established model is used to simulate the flow and heat transfer process of molten. The Volume of Fluid (VOF) method is used to study the formation and collapse of the keyhole and the formation of bubbles. It is found that bubbles are easy to form when the keyhole depth abruptly changes. There are three main forms of bubbles formed by keyhole instability. The front wall of the keyhole collapses backward to form a bubble. The back wall of the keyhole inclines forward to form a bubble. The lower part of the keyhole produces a necking-down effect, and the lower part of the keyhole is isolated separately to form a bubble. In addition, when the keyhole does not penetrate the base metal, the stability of the keyhole is high and the percentage of porosity is low.

Abstract Cardiac rehabilitation program is well‐established but the Rehabilitation After Myocardial Infarction Trial (RAMIT) is reported that it does not affect mortality and morbidity of patients after myocardial infarction during follow‐up period. The objectives of the study were to compare functional walking capacity, risk factor control, and morbidities in follow‐up for cardiac rehabilitation (exercise + education), exercise only, and usual care among patients with coronary artery disease. A total of 492 male and female patients (age range: 45–73 years) with coronary artery disease after myocardial infarction or underwent percutaneous coronary intervention or coronary artery bypass grafting surgeries referred to cardiac rehabilitation were included in the study. Patients were participating in a cardiac rehabilitation program (exercise + education, CRP cohort, n = 125), exercise only (USC cohort, n = 182), or usual care (NCR cohort, n = 185). Data regarding incremental shuttle walk test, lipid profile, the Patient Health Questionnaire 9, and morbidities in follow‐up of patients were retrospectively collected and analyzed. After completion of 1 year, cardiac rehabilitation program (p

Laser-MIG hybrid multi-layer welding (LMHMW) technology has been employed in paraxial configuration with laser leading for the welding of 20 mm thick Q235 carbon steel plates to exploit the hybridization effect that addresses the shortcomings of the individual process as well as to compliment their merits. The bilateral effects of arc augmented laser welding have resulted in complete joint penetration, process efficiency, stability and gap bridge ability. Samples welded under varying heat inputs in multiple passes have been analyzed for their microstructure evaluation using an optical microscope followed by tensile and Vickers hardness testing in various regions of the weld zones. This process was conducted to characterize the effect of heat input on the mechanical properties of the welded joints. The experimental results illustrate that different heat inputs have significant effects on the microstructure, heat affected zone width and mechanical properties of welded joints. The microhardness near the fusion line decreases dramatically due to the influence of the phase transformation process, and the highest microhardness value is obtained in the center of the weld seam. By using reasonable process parameters, the strength of the welded joint can obtain 458.5 MPa.

Hybrid laser arc welding (HLAW) features advantages such as higher welding speed and gap tolerance as well as smaller welding deformation and heat-affected zone than arc welding. Porosity in hybrid laser arc weld due to keyhole fluctuation tends to be the initial source of crack propagation, which will significantly diminish the weld performance. A high-speed imaging technique was adopted to record and analyze the droplet transfer and keyhole fluctuation behavior during hybrid laser arc welding of aluminum alloys. A heat transfer and fluid flow model of HLAW was established and validated for a perspective of the evolution process of droplet transfer and keyhole fluctuation. The relationship between keyhole fluctuation and weld porosity was also revealed. During the droplet transfer stage, liquid metal on the top surface of the weld pool flows toward the keyhole originated by globular transfer, and the keyhole fluctuates and decreases significantly, which has a higher tendency to form a bubble in the weld pool. The bubble evolves into porosity once trapped in the mush-zone near the trailing edge of the weld pool. Therefore, globular transfer during HLAW is the principal origin of keyhole fluctuation and weld porosity. Welding current has a significant influence on keyhole fluctuation and weld porosity rate. Droplet transfer frequency, keyhole fluctuation, and porosity rate increase with higher welding current under the globular transfer mode. The porosity rate shows a nearly positive correlation with the standard deviation of keyhole fluctuation.

Specific energy is a key process parameter during laser cladding of high entropy alloy (HEA); however, the effect of specific energy on the microstructure, hardness, and wear resistance of HEA coating has not been completely understood in the literature. This paper aims at revealing the influence of specific energy on the microstructure and properties of laser cladded FeCoCrNi high entropy alloy on the Ti6Al4V substrate, and further obtains feasible process parameters for preparation of HEA coating. Results indicate that there are significant differences in the microstructure and properties of the coatings under different specific energy. The increase of specific energy plays a positive role in coarsening the microstructure, promoting the diffusion of Ti from the substrate to HEA coating, and subsequently affects the hardness of samples. The HEA coating is mainly composed of the face-centered cubic phase and body-centered cubic phase, precipitating a small amount of Fe-Cr phase and Laves phase. Metallurgical bonding is obtained between the base metal and the coatings of which the bonding region is mainly composed of columnar crystal and shrinkage cavities. The microhardness of the HEA coating reaches 1098 HV, which is about 200% higher than that of the TC4 substrate, and the wear resistance is significantly improved by the HEA coating.

Using a dynamic perspective this article examines, the general situation of the development of South Korean direct investment in China since 1992, when the two countries established diplomatic relations. It probes many characteristics of South Korean direct investment in China: its late start yet rapid rise; the smaller average value of Korean project investments; the accelerated process of localization by large South Korean enterprises in China; the diversified industrial distribution; and the wide-ranging geographical distribution. It analyses the reasons for the rapid increase in South Korean investment in China: the use of China's low-priced production factors, the direct entry of South Korean enterprises into the Chinese market, and the stable investment environment with fewer labor disputes that China provides. Finally, this article also proves that South Korean enterprises have achieved satisfactory results from their direct investment in China.

Background and objective The treatment for early-stage non-small cell lung cancer is primarily surgical. However, the optimal extent of mediastinal lymph node resection remains to be determined. The aim of the current study is to investigate the effect of a pulmonary wedge resection on aged patients with lung cancer. Methods A total of 15 lung cancer patients aged over 70 years were treated via video-assisted thoracoscopic surgery (VATS) wedge resection and mediastinal lymph node sampling from June 2004 to February 2008. Mediastinal lymph node sampling included stations 2R, 4R, 8 and 9 for the right-sided cancers and stations 5, 6, 8 and 9 for the left-sided cancers. Results VATS wedge resection and mediastinal lymph node sampling for aged patients with peripheral lung cancer are minimally invasive treatments with a short operative time and low postoperative morbidity. The 1-year and 3-year survival rates were 100% and 86.6%, respectively. Conclusion VATS wedge resection and mediastinal lymph node sampling can be an alternative treatment for aged patients with early peripheral lung cancer.

Objective • To investigate the efficacy and long-term results of transabdominal preperitoneal prosthesis (TAPP) in the treatment of patients with unilateral inguinal hernia (UIH). Methods • Ninety-two patients with UIH admitted to our hospital from January 2017 to August 2021 were selected to be the study subjects of this trial. They were divided into two groups with 46 patients in each, based on whether they were treated with a transabdominal preperitoneal prosthesis (TAPP group) or an open Bassini repair (OBR group). The clinical data of both groups were compared in terms of surgery (time and bleeding), postoperative (length of stay and costs), postoperative (near and far) complications, visual analog (VAS) score within 6 months after surgery, and postoperative SF-36 health survey scale. Results • The mean operative time and intraoperative bleeding were lower in the TAPP group than in the OBR group (P < .05), the postoperative hospital stay was shorter in the TAPP group than in the OBR group (P < .05), and the hospital costs were markedly higher in the TAPP group than in the OBR group (P < .05). There was no remarkable difference in the occurrence of postoperative complications between the two groups. The mean VAS score and SF-36 score profiles were better in the TAPP group than in the OBR group at 3 and 14 days after surgery (P < .05), and there were no marked differences in VAS score and SF-36 score profiles between both groups at 2-month and 6-month postoperative follow-up (P > .05). Conclusion • TAPP is effective in treating patients with UIH, improving their pain and quality of life, and safeguarding their health. [ABSTRACT FROM AUTHOR]

The spatiotemporal characteristics of the Antarctic ice sheet (AIS), as constrained by geodetic observations, provide us with a deeper understanding of the current evolution of ice mass balance. However, it still needs further in-depth research on interannual fluctuations and long-term trends of ice mass changes throughout the AIS. In this study, these two aspects were quantitatively analyzed through global positioning system (GPS) and gravity recovery and climate experiment/follow on (GRACE/GFO) over the past two decades. The nonlinear variation of GPS-inferred vertical land motion (VLM) and the influence of surface elastic load are of particular concern. The principal component analysis method is utilized to extract common mode signals from GPS time series, while correcting for various surface loads. The first principal components (PCs) accounted for 57.67%, 35.87%, 36.28%, and 36.03% of the total variances in the vertical components for GPS raw, atmospheric + nontidal oceanic (AO)-removed, AO + hydrographic model (AOH)-removed, and AO + GRACE/GFO-based load (AOG)-removed, respectively. Furthermore, the GPS vertical velocity, excluding the common mode component + AOG, yielded a median value of 0.13 mm/yr, which indicates that the retreat of ice mass has made a significant contribution to the GPS-observed VLM. In addition, the glacial isostatic adjustment (GIA) effect is found to play a key role in the large-scale VLM uplifting of the West AIS. After evaluating five different GIA models with GPS vertical velocity, we suggest that the ICE-6G_D model can more effectively correct GIA signals in GPS observations over Antarctica.

Abstract Mitochondrial dysfunctions are closely associated with different types of disease, including cancer. Carnitine acetyltransferase (CRAT) is a mitochondrial-localized enzyme catalyzing the reversible transfer of acyl groups from an acyl-CoA thioester to carnitine and regulates the ratio of acyl-CoA/CoA. Our bioinformatics analysis using public database revealed a significant decrease of CRAT expression in ovarian cancer (OC). However, the functions of CRAT have rarely been investigated in human cancers, especially in OC. Here, we found a frequent down-regulation of CRAT in OC, which is mainly caused by up-regulation of miR-132-5p. Downregulation of CRAT was significantly associated with shorter survival time for patients with OC. Forced expression of CRAT suppressed OC growth and metastasis by inducing cell cycle arrest and epithelial to mesenchymal transition (EMT). By contrast, CRAT knockdown promoted OC growth and metastasis. Mechanistically, we found that CRAT downregulation promoted OC growth and metastasis by increasing mitochondrial biogenesis to facilitate mitochondrial metabolism through reducing the acetylation of peroxisome proliferator-activated receptor-γ coactivator (PGC-1α). In summary, CRAT functions as a critical tumor suppressor in OC progression by enhancing PGC-1α-mediated mitochondrial biogenesis and metabolism, suggesting CRAT as a potential therapeutic target in treatment of OC.

Abstract The comprehensive benefit evaluation of LID based on multi-criteria decision-making methods faces technical issues such as the uncertainties and vagueness in hybrid information sources, which can affect the overall evaluation results and ranking of alternatives. This study introduces a multi-indicator fuzzy comprehensive benefit evaluation approach for the selection of LID measures, aiming to provide a robust and holistic framework for evaluating their benefits at the community level. The proposed methodology integrates quantitative environmental and economic indicators with qualitative social benefit indicators, combining the use of the Storm Water Management Model (SWMM) and ArcGIS for scenario-based analysis, and the use of hesitant fuzzy language sets and Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) for decision-making. The framework’s novelty lies in the integration of the hesitant fuzzy weighted average algorithm to handle subjective uncertainties in expert judgment and the incorporation of multi-return period scenarios to enhance the robustness of the evaluation. The comprehensive benefits of 26 LID configurations were conducted in Chenglong Road Subdistrict under five rainfall return period scenarios of 5, 10, 20, 50, and 100 years. The results show that LID measures, particularly combinations of sunken green spaces and permeable paving, offer significant reductions in runoff and peak flow, along with improved flood mitigation across multiple return periods. Additionally, this study identifies practical LID implementation priorities for local decision-makers. The relative closeness is influenced by the indicators and non-calibrated parameters. However, it overall does not affect the main trends and key insights derived. The robustness of the proposed approach is reinforced by four key aspects: the impact of the Thiessen polygon method in ArcGIS, the influence of composite runoff coefficient and iterative optimization in SWMM, the effect of hesitant fuzzy linguistic sets and TOPSIS on weight calculation, and the contribution of simulations under different return periods to stability analysis.

Abstract Aim and objectives To construct a set of scientific and feasible nursing management protocols for early fluid resuscitation in acute pancreatitis (AP) patients that can be used to guide clinical practice and enhance the treatment efficacy in these patients. Background Fluid resuscitation is a key means of early treatment for AP patients and has become a clinical consensus. Nurses are important practitioners of fluid resuscitation, and there is a lack of specific enforceable nursing management programs. Methods Through literature research, on-site research, semi-structured interviews, and other preliminary preparations of the first draft of the nursing management program for early fluid resuscitation in acute pancreatitis, the Delphi method was used to conduct two rounds of correspondence with medical and nursing experts, and then statistically analyzed. Results Fifteen and 14 questionnaires were distributed in two rounds, respectively, and 15 and 14 questionnaires were recovered, respectively. The positive coefficient of experts was 100%, the authority coefficient was 0.970 and 0.975, respectively; the coefficient of variation coefficient was 0.05–0.21 and 0.00–0.20, respectively; the expert coordination coefficients of all levels of indices in this study are 0.166–0.335 and 0.189–0.364, respectively. The P values of the first, second, and third level indices are

The relationship between tensile strength, wire feeding speed and travel speed is built based on Back Propagation (BP) neural network during the wire arc additive manufacturing (WAAM) process. The introduction of a genetic algorithm for optimising the BP neural network (GA-BP) and incorporation of additional parameter combinations through the forward model markedly enhance the prediction accuracy of the process parameter reversemodel. The BP neural network with a genetic algorithm model exhibits excellent training results, and the sample population regression reaches 0.97. An error value of the optimised model is only 3.10% for wire feeding speed prediction, only 1.55% for travel speed prediction. The GA-BP reverse model optimises WAAM process parameters and achieves a tensile strength exceeding 230MPa. [ABSTRACT FROM AUTHOR]

The Metaverse depicts a parallel digitalized world where virtuality and reality are fused. It has economic and social systems like those in the real world and provides intelligent services and applications. In this paper, we introduce the Metaverse from a new technology perspective, including its essence, corresponding technical framework, and potential technical challenges. Specifically, we analyze the essence of the Metaverse from its etymology and point out breakthroughs promising to be made in time, space, and contents of the Metaverse by citing Maslow's Hierarchy of Needs. Subsequently, we conclude four pillars of the Metaverse, named ubiquitous connections, space convergence, virtuality and reality interaction, and human-centered communication, and establish a corresponding technical framework. Additionally, we envision open issues and challenges of the Metaverse in the technical aspect. The work proposes a new technology perspective of the Metaverse and will provide further guidance for its technology development in the future.© 2022 Published by Elsevier Ltd.