In recent years, the application of the difficult-to-machine materials has increased gradually, and the challenging requirements have been placed on cutting. The difficult-to-machine materials suffer ...from limitations such as large cutting force, high cutting temperature and serious cutting tool wear during processing. In order to improve the cutting performance of cutting tools and attain sustainable development, the green cutting technology has been gradually developed. The cutting tool surface micro-texture and coating represent the key technologies for attaining the green cutting performance. These technologies can improve the cutting performance, thereby prolonging the cutting tool life and improving the workpiece surface quality. This study systematically expounds the latest progress in the field of micro-textured cutting tools, coated cutting tools and micro-textured coated cutting tools. It introduces the existing micro-texture and coating preparation processes and analyzes the mechanism of micro-texture and coating. The compiles the recent developments in the materials and structures, along with summarizing the effect of micro-texture, coating and micro-texture coating synergy on cutting tool performance, cutting performance and workpiece surface quality. Finally, it presents the future development trend for the micro-textured cutting tools, coated cutting tools and micro-textured coating cutting tools. Overall, this study acts as a benchmark for the follow-up development in the field of green cutting technology.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Compared to conventional tools, the cutting performance of microtextured tools is significantly better. Laser surface texturing (LST) is the most important technique for producing a microstructure. ...The modification of microstructure properties of tools by LST has not received much attention. In this study, the effects of LST on the microstructural properties of tools were investigated, and the specific causes of the improvement in wear resistance of tools by laser micro texturing and the effects of micro-texture on adhesive wear of tools were revealed. In this study, microtextured tools with different laser parameters were fabricated and the test was conducted for cutting titanium alloys. The changes in tool microstructural properties and tool wear morphology were compared and analyzed. LST effectively reduces the release of co-elements during cutting, solidifies WC particles, and reduces the adhesive and oxidative wear of the tool. In addition, the micro-texture and surrounding annular protrusions significantly reduce cutting heat, which in turn reduces diffusive and abrasive wear. In this context, the morphology of the micro-texture facilitates adhesive fracture and peeling of the adhesive wear, while the annular protrusions help reduce tool wear. Their interaction significantly improves the wear resistance of laser-machined microtextured tools.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The role of cancer cell FOXP3 in tumorigenesis is conflicting. We aimed to study FOXP3 expression and regulation, function and clinical implication in human non-small cell lung cancer (NSCLC).
One ...hundred and six patients with histologically-confirmed NSCLC who underwent surgery were recruited for the study. Tumor samples and NSCLC cell lines were used to examine FOXP3 and its related molecules. Various cell functions related to tumorigenesis were performed. In vivo mouse tumor xenograft was used to confirm the in vitro results.
NSCLC patients with the high level of FOXP3 had a significant decrease in overall survival and recurrence-free survival. FOXP3 overexpression significantly induced cell proliferation, migration, and invasion, whereas its inhibition impaired its oncogenic function. In vivo studies confirmed that FOXP3 promoted tumor growth and metastasis. The ectopic expression of FOXP3 induced epithelial-mesenchymal transition (EMT) with downregulation of E-cadherin and upregulation of N-cadherin, vimentin, snail, slug, and MMP9. The oncogenic effects by FOXP3 could be attributed to FOX3-mediated activation of Wnt/β-catenin signaling, as FOXP3 increased luciferase activity of Topflash reporter and upregulated Wnt signaling target genes including c-Myc and Cyclin D1 in NSCLC cells. Co-immunoprecipitation results further indicated that FOXP3 could physically interacted with β-catenin and TCF4 to enhance the functions of β-catenin and TCF4, inducing transcription of Wnt target genes to promote cell proliferation, invasion and EMT induction.
FOXP3 can act as a co-activator to facilitate the Wnt-b-catenin signaling pathway, inducing EMT and tumor growth and metastasis in NSCLC.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Studies have found that milling with an inclined plane when using ball-end milling cutters can reduce heating of the cutting tool. It has also been found that micro-textures on the rake face can play ...a role in the reduction of friction and wear. Taking these things together, milling titanium alloy with micro-textured ball-end milling cutters with workpieces at an inclined angle can have a significant influence on tool wear and the surface quality of machined workpieces. We have therefore looked at the factors affecting the quality of machined surfaces using an orthogonal test and, in particular, the effect of different micro-texture parameters and different workpiece inclination angles. Through means of an extreme difference analysis, the primary and secondary relationship between micro-texture parameters, workpiece inclination angles, and surface roughness is assessed. The analysis focuses in particular on the distance between micro-pits, micro-pit diameter, the workpiece inclination angle, the distance between the first row of micro-pits and the cutter edge, and the depth of the micro pits. On the basis of the analysis, a model that can predict surface roughness is established that provides a means of optimizing micro-textured cutter design and machining inclination angles when milling titanium alloy.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Titanium alloys generally have problems such as sticking, large cutting force, and poor heat dissipation during the cutting process., research shows that processing microtextures on the surface of ...the tool can effectively improve the above problems. Therefore, this paper designs the V-groove micro-textures based on the principle of bionics. Use simulation software to analyze the milling behavior of different V-groove micro-texture ball-end milling cutters for milling titanium alloys. Build a test platform to study the milling performance of the V-groove micro-texture ball-end milling cutter for milling titanium alloys, obtain the prior choice range of V-groove micro-texture parameters, optimize the parameters based on the simulated annealing algorithm and conduct experimental verification. The results of the optimal tool parameters are that the opening angle of the V-groove micro-textures is 79°, the V-groove micro-texture spacing is 170 µm, and the V-groove micro-texture width is 30 µm, the distance from blade of the V-groove micro-textures is 90 µm.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The mammalian cerebral cortex undergoes a strictly regulated developmental process. Detailed in situ visualizations, imaging of these dynamic processes, and in vivo functional gene studies ...significantly enhance our understanding of brain development and related disorders. This review introduces basic techniques and recent advancements in in vivo electroporation for investigating the molecular mechanisms underlying cerebral diseases. In utero electroporation (IUE) is extensively used to visualize and modify these processes, including the forced expression of pathological mutants in human diseases; thus, this method can be used to establish animal disease models. The advent of advanced techniques, such as genome editing, including de novo knockout, knock-in, epigenetic editing, and spatiotemporal gene regulation, has further expanded our list of investigative tools. These tools include the iON expression switch for the precise control of timing and copy numbers of exogenous genes and TEMPO for investigating the temporal effects of genes. We also introduce the iGONAD method, an improved genome editing via oviductal nucleic acid delivery approach, as a novel genome-editing technique that has accelerated brain development exploration. These advanced in vivo electroporation methods are expected to provide valuable insights into pathological conditions associated with human brain disorders.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Parametric optimisation of micro-texture is important to improve the performance of cutting tool in metal cutting. In this study, the simulation models of micro-textured surface of cemented carbide ...are established by using ABAQUS platform, and fictitious stress distribution is analysed to select the optimum micro-texture structure. Then, many friction tests were carried out to compare the several different micro-textures. Based on the experimental data, the parametric optimisation model of micro-texture on cemented carbide surface is established, and its significant analysis is carried out. Moreover, the optimised parameters are applied to the ball-nose end mill in the machining of titanium alloy. The results show that the micro-texture can absorb stress and change the status of stress distribution on the surface. Among the micro-texture structures, the performance of micro-pit is the best one, i.e. surface stress micro-pit-texture is distributed uniformly, and the stress concentration micro-pit-texture is low, when the micro-pit-texture’s diameter is 46.6 μm, its depth is 27 μm, and its distance is 123 μm. The ball-nosed end mill with the optimised parameters has a stronger wear resistance than a normal tool.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The control variable method is a method to study the influence of a certain factor on the result quantity by artificially controlling other factors. Some researches have shown that a micro-texture ...can effectively reduce the surface work-hardening degree of the tool surface. Therefore, in this study, based on the control variable method, a micro-texture ball-end milling cutter was used to mill titanium alloy. The influence rules of micro-texture distance from edge, micro-texture distribution type and mode and cutting stroke on work hardening degree were analysed. The results show that the surface work-hardening degree was the smallest(118%) at a distance of 90 μm from the cutting edge and at a 0.3° offset angle. When the micro-texture is micro-pit texture, the work hardening degree is 121% and is minimum. The content of the O element in the surface modification layer of the micro-textured tool is 6.97%, which is less than 16.17% of that of the non-textured tool, and the content of the C element is 4.95% and 4.97% respectively. The results show that the micro-texture placement can effectively reduce the oxidation degree and work hardening degree of the machined surface of the milled titanium alloy.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The period fertility in China has declined to very low levels, and the completed cohort fertility rate (CFR) has also decreased significantly. However, the exact fertility rate remains controversial. ...While the tempo effect has played a significant role in China's period fertility decline, child underreporting has to be taken into consideration in China's fertility research.
By using the census data from 1982 to 2010, and the 1% population sample survey data from 1995 to 2015, we systematically analyzed China's fertility and its trends since the 1980s using period fertility measures, adjusted period fertility measures, cohort fertility measures, and indirect estimation methods.
The results show that marriage postponement significantly affects the TFR decline. Even after eliminating the tempo and parity structure effect, the adjusted TFR has fallen below 1.5, and the first-order fertility rate dropped to 0.9 in 2015. The CFR for women aged 45-49 declined from 5.37 in 1982 to 1.62 in 2015 mainly because of a decrease in fourth and higher-order births from 1982 to 1990, a decrease in second and third births from 1990 to 2000, and a decrease in second births from 2000 to 2015. Indirect estimation methods yielded a TFR in the range of 1.5-1.6 for the period 2000-2010 and an average TFR of 1.49 for the period 2011-2020.
The traditional norm of universal marriage and childbearing for Chinese women is changing. China's fertility has been steadily declining, as measured by both period and cohort indicators. Following the historical change, fertility may continue to decline even after introducing the universal three-child policy in China in 2021.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Given the serious work hardening phenomenon, high chemical activity, severe tool wear, and poor workpiece surface quality during the cutting of titanium alloys, placing micro-texture on the tool ...surface decreases the tool-chip contact area and friction and plays the role of wear resistance and friction reduction. In order to improve the cutting performance of cutting tools, the present study examins the effect of micro-texture parameters of a cemented carbide ball-end milling cutter on cutting force, tool wear, and workpiece surface roughness and establishes a regression analysis model via regression analysis. We consider the cutting performance of a cemented carbide micro-texture ball-end milling cutter as an evaluation standard. A genetic algorithm is applied to the multi-objective optimization of micro-texture parameters, and a regression analysis model of micro-texture design criteria is established. This provides a standardised reference to select standard micro-texture parameters in the design and preparation of a cemented carbide micro-texture ball-end milling cutter.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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