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Severe burns are devastating injuries with significant immune dysfunction and result in substantial mortality and morbidity due to sepsis induced organ failure. Acute lung injury is the most common type of organ injury in sepsis, however, the mechanisms of which are poorly understood and effective therapeutic measures are limited. This study is aimed to investigate the effect of a small Guanosine triphosphatase (GTPase), Adenosine diphosphate ribosylation factor 6 (ARF6), on burn sepsis induced lung injury, and discuss the possible mechanisms. Burn sepsis was established in male C57BL/6 mice. Mice were anesthetised by intramuscular injection of ketamine and xylazine hydrochloride, then 30% TBSA full thickness burn followed by sub-eschar injection of lipopolysaccharide. Animals were treated with intraperitoneal injection of a small molecule inhibitor of ARF6: NAV-2729, or vehicle, right after the burn and sepsis stimuli were inflicted. Lung tissues were harvested for histopathological observation and the acute lung injury scores were calculated. Organ permeability, Vascular Endothelial Cadherin (VE-cadherin) expression, inflammatory cytokine levels and myeloperoxidase activity in lung tissues were detected. Rat pulmonary microvascular endothelial cells (PMVECs) were stimulated by burn sepsis serum with or without 10 μM NAV-2729. The ARF6 activation, VE-cadherin expression, inflammasome activity, adapter protein apoptosis speck-like protein containing a caspase recruiting domain (ASC) specks and cytokines secretion were determined. Student's t test was used for comparison between two groups. Multiple comparisons among groups were performed by using analysis of variance, with Tukey's test for the post hoc test. NAV-2729 treatment attenuated burn sepsis induced lung injury and promoted survival of burn septic mice by preserving VE-cadherin expression in endothelial cell adherent junction and limited vascular hyperpermeability in lung tissues. Moreover, inflammatory cytokine expression and inflammatory injury in lung tissues were alleviated. Mechanistically, NAV-2729 enhanced vascular integrity by inhibiting ARF6 activation and restoring VE-cadherin expression in PMVECs. In addition, NAV-2729 inhibited ARF6-dependent phagocytosis of ASC specks, thus preventing inflammation propagation mediated by cell-to-cell transmission of ASC specks. ARF6 inhibition preserved vascular integrity by restoring expression of VE-cadherin and suppressed the spread of inflammation by affecting phagocytosis of ASC specks, thus protected against sepsis induced lung injury and improve survival of burn septic animals. The findings of this study implied potential therapeutics by which ARF6 inhibition can protect lung function from septic induced lung injury and improve outcomes in burn sepsis. • ARF6 inhibition is effective to preserve vascular integrity in burn sepsis. • ARF6 inhibition restrain both vascular leakage and excessive inflammatory cascade. • Inhibiting ARF6 does not affect the primary inflammatory response in burn sepsis. • ARF6 inhibition could be a promising potential therapeutic to protect against burn sepsis induced lung injury. [ABSTRACT FROM AUTHOR]

Covalent Organic Frameworks (COFs) are widely used for photocatalysis but limited by the aggregation of the catalysts, which limited the mass transfer. Herein, corn stalk cores were used as the substrate, and two kinds of biomass based COFs with different electronic structures of thiophene (C@SCOF) and pyridine (C@NCOF) were in-situ fabricated uniformly on the surface of the substrate. In this way, COFs expose more active sites rather than embedding in the agglomerated structure. Biomass based COFs, especially C@SCOF, exhibit a hierarchical porous structure containing micropores and macropores, which offer fast mass transfer channels for the catalytic and adsorbed substrates. Therefore, the biomass based COFs utilized more efficiently to achieve higher photocatalytic performance. The C@SCOF with D-A structure displays stronger photoresponse and lower impedance, which promote the dissociation of a photogenerated exciton and carrier separation efficiency, resulting remarkable photocatalytic performance for oxidation of benzylamine coupling reaction. This work could guide the design and preparation of biomass-based hybrids with promising performance. [Display omitted] • Two different electronic structured biomass based COFs were constructed. • Hierarchical porous structure exposes more active sites and improved mass transfer. • Biomass based COFs showed stable structure and good reusability. • C@SCOF with D-A structure and porosity showed better photocatalytic performance. [ABSTRACT FROM AUTHOR]

The direct impact of diamond wire slicing on the cost of subsequent silicon wafer processing underscores the significance of reducing slicing costs for both the integrated circuit and photovoltaic industries. Effectively and reasonably evaluating monocrystalline silicon wafer quality is thus a crucial challenge. In this paper, fractal theory was used to analyze the monocrystalline silicon wafer sawn surfaces combining with surface roughness measurement. The findings reveal the presence of scratches, pits, and prominent saw marks on the sawn surface. Notably, the surface roughness is significantly higher along the feed direction compared to that along the wire direction. Moreover, an increase in the ratio of feed speed to wire speed leads to a rougher surface. The fractal dimension of the sawn surface is inversely proportional to its roughness, indicating that a higher fractal dimension corresponds to a finer surface texture. Moreover, the two dimensional fractal dimension can effectively capture the anisotropic characteristics of monocrystalline silicon wafers. The two dimensional fractal dimension of the wafer surface obtained by removing materials in ductile mode has a strong symmetry. However, the two dimensional fractal dimension of the surface obtained in brittle mode fluctuates obviously and is weakly symmetric. By combining traditional surface roughness analysis with fractal methods, we can gain insights into the material removal mechanisms involved in slicing monocrystalline silicon wafers using diamond wire, which is of great significance for optimizing diamond wire slicing. [ABSTRACT FROM AUTHOR]

Esophageal cancer is one of the most common digestive malignant diseases worldwide and emerging evidences revealed that microRNAs (miRNAs) were implicated in the development and progression of esophageal cancer. However, the expression level and biological function of microRNA-873(miR-873) in esophageal cancer are still largely elusive. In this study, we investigated the expression and biological roles of miR-873 in human esophageal cancer. Our results revealed that miR-873 was significantly underexpressed in esophageal cancer tissues and cell lines when compared with the para-tumor tissue and primary human esophageal epithelial cells. Furthermore, overexpression of miR-873 could remarkably inhibit esophageal cancer cell growth, migration and invasion. Moreover, we validated differentiated embryonic chondrocyte expressed gene 2 (DEC2) as a direct target of miR-873 which could reverse the repressive effects of miR-873 on esophageal cancer cell. In summary, our investigation demonstrated that miR-873 was underexpressed in esophageal cancer and might act as a tumor suppressor gene by directly targeting DEC2. [ABSTRACT FROM AUTHOR]

In this paper, the effects of multi-radii geometry of inserts on material removal rate (MRR) and surface integrity are studied. An innovative model was developed based on the Monte Carlo method to predict the MRR during turning with different tool nose geometries and the maximum prediction error was controlled within 2.7%. The results demonstrated that both roughness heights and irregularities of the machined surfaces were half reduced by using multi-radii wiper inserts compared to those obtained by conventional inserts. Feed rate was optimized as 0.4 mm/rev in turning with wiper inserts. As a result, surface integrity improves by 41.45% and energy consumption reduces by 4.25%. The corrosion resistance of the AISI 1045 steel was improved by the laser cladding and high feed rate turning process chain. Turning with feed rate of 0.4 mm/rev provided the highest corrosion resistance. The premise of using multi-radii wiper inserts for higher MRR while maintaining good surface integrity was realized. Such conditions determined finishing process of remanufactured parts and the obtained minimization of specific cutting energy enabled sustainable manufacturing process. [ABSTRACT FROM AUTHOR]

Laser cladding has been widely used to repair some high value-added parts for remanufacturing or sustainable production. Additional machining is necessary when the repaired parts require high precision and high quality. However, using conventional cutting theory to machine cladding workpiece is always a challenging work. The depth of cut in machining cladding workpiece is restricted in a shallow range and exhibits comparable to the thickness of cladding. It is meaningful to explore the critical conditions for orthogonal machining two-layered workpiece formed by laser cladding. The critical condition was defined as an initiation of plastic deformation in substrate while elastic deformation still occurring in the bottom of cladding. These different deformation mechanisms attributed to the inferior physical-mechanical characteristics of the substrate compared to the cladding. The stresses induced by machining can reach the cladding-substrate interface and result in a premature plastic deformation in substrate. As a result, discontinuous plastic deformation zones generated in both subsurface and substrate. For this reason, a coupled thermo-mechanical model was developed to predict the plastic deformation behaviors in subsurface and substrate materials. It was found that the ratio of uncut chip thickness to critical cladded thickness ranged from 0 to 0.678 with increase of uncut chip thickness. It meant that the thicker the cladding was, the more difficult it would be to induce a premature plastic deformation in the substrate. Lower cutting force but higher specific cutting energy was found under lower uncut chip thickness. Thinner cladding was not recommended for purpose of repairing. The results are expected to provide fundamentals to weigh pre-cladded thickness and cutting parameters in a post machining process for manufacturing sustainability. [ABSTRACT FROM AUTHOR]

Wiper insert have the characteristics of achieving an excellent surface finish and improving the productivity in turning processes. Wiper insert can provide twice feed rate while maintaining the comparable surface roughness compared to that provided by the conventional insert. In the present study, surface topographies in finish turning with conventional and wiper inserts are investigated. The key element of this work is that the cutting edge path equation in the cutting tool coordinate system is transformed into the machine tool and workpiece coordinate system by the use of spatial coordinate transformation. Following that a surface topography simulation algorithm based on the cutting edge path equation and cutting parameters is put forward. The output of this work is that both the simulated surface topography and surface roughness profile are good agreement with the experimental results. Both the simulated and the actual machined surface results show that better surface topography is obtained in finish turning with the wiper insert than that with conventional insert. Burnishing effect of the wiper insert leads to half decrease of the Ra and Rz . The actual surface profiles are no longer regular wave shapes due to ploughing effect and side flow existing in the cutting zone. In addition, a surface roughness map has also been developed to optimize the selection of wiper radius and feed rate to satisfy the requirement of surface finishing with higher productivity. From the viewpoint of cutting tool design, the wiper radius with five times larger than tool nose radius can fully come into its role. This provides a novel insight into the design of wiper insert over conventional techniques. Above all, the proposed model gives a better prediction of surface roughness in finish turning process compared to the previous empirical and regression roughness models. The prediction of surface roughness in finish turning with wiper insert is also realized. [ABSTRACT FROM AUTHOR]

The physical-mechanical and electrochemical corrosion behaviors of additively manufactured Cr-Ni-based stainless steel were investigated. Microstructural characterizations of the claddings were tested utilizing EDS, XRD, SEM instruments. Microhardness and nano-indentation measurements were executed to evaluate the mechanical properties. Electrochemical corrosion behaviors of the claddings were evaluated in 10 wt.% NaCl solution, compared with AISI 1045 and 304L steels. The claddings showed the main peaks corresponding to the α-Fe and substitutional solid solution phases. The dendritic austenite and interdendritic ferrite phases grew up under the high solidification and cooling rate. The porosity level of 0.48% in area per cent with a mean pore size of 0.04 μm was measured due to high energy delivered by the laser beam and good wettability of the powders. Microhardness of the claddings was found to be 550 HV 0.05 , indicating higher value compared to the substrate (250 HV 0.05 ). Besides, material constitutive model was proposed by a power law description based on the reverse algorithm. The high yield strength reflected a difficult-to-cut potential in the subsequent cutting process. Moreover, the cladding provided the best corrosion resistance, followed by AISI 304L stainless steel, and AISI 1045 steel the worst. Pitting corrosion was prone to occur in enriched chloride environments. [ABSTRACT FROM AUTHOR]

Text recognition, especially for complex scripts like Chinese, faces unique challenges due to its intricate character structures and vast vocabulary. Traditional one-hot encoding methods struggle with the representation of hierarchical radicals, recognition of Out-Of-Vocabulary (OOV) characters, and on-device deployment due to their computational intensity. To address these challenges, we propose HierCode, a novel and lightweight codebook that exploits the innate hierarchical nature of Chinese characters. HierCode employs a multi-hot encoding strategy, leveraging hierarchical binary tree encoding and prototype learning to create distinctive, informative representations for each character. This approach not only facilitates zero-shot recognition of OOV characters by utilizing shared radicals and structures but also excels in line-level recognition tasks by computing similarity with visual features, a notable advantage over existing methods. Extensive experiments across diverse benchmarks, including handwritten, scene, document, web, and ancient text, have showcased HierCode's superiority for both conventional and zero-shot Chinese character or text recognition, exhibiting state-of-the-art performance with significantly fewer parameters and lower floating-point operations (FLOPs). • HierCode represents Chinese characters using hierarchical encoding and prototype learning. • HierCode exhibits lightweight characteristics and lower FLOPs. • HierCode achieves SOTA results in zero-shot Chinese character and line recognition. [ABSTRACT FROM AUTHOR]

• An empirical fracture model based on the maximum strain principle is proposed. • The new model takes into account the embrittlement effect of high strain rate, and. • Can predict the ductile fracture of materials in the full range of strain rate. At different deformation rates, a ductile material may fail by isothermal deformation fracture, thermoplastic shear instability, or even brittle fracture. The failure mode transition at sound speed deformation rate has not been well described. This paper aims to establish a new fracture model which considers the strain rate embrittlement effect (SREE) at the sound speed deformation rate, and can be used to predict the failure of the material in a large range of strain rate. Taking pure iron DT 8 as the experimental material, impact tests of pure iron specimens under different stress states, strain rates, and temperatures were carried out. Fracture strains under different stress states, strain rates, and temperatures were obtained. The strain rate was increased to 227450/s (5.36/s in log10) to obtain the ductile–brittle transition point. A new fracture model is proposed to describe the evolution of fracture strain over the wide range of strain rate. The new proposed model is experimentally validated and compared with the J-C failure model. It shows the new proposed fracture model can predict the ductile fracture behavior of a ductile material in the full strain rate range, and capture the failure mode transition at the sound speed deformation rate of a material. [ABSTRACT FROM AUTHOR]