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We analyze the general equilibrium effects of countercyclical unemployment benefit policies. Our heterogenous-agent model features costly job search with imperfect insurance of unemployment risk and individual savings. Our model predicts: (1) the additional unemployment under a countercyclical policy relative to that under an acyclical policy to be a superlinear function of the aggregate shock?s size, (2) a higher unemployment rate sensitivity to UI policy changes when individual savings are relatively low. Our estimates of the effects of UI policy changes are based on transition dynamics following a large, unanticipated increase in the unemployment rate. [ABSTRACT FROM AUTHOR]

Rapid developments in satellite remote-sensing technology have enabled the collection of geospatial data on a global scale, hence increasing the need for covariance functions that can capture spatial dependence on spherical domains. We propose a general method of constructing nonstationary, locally anisotropic covariance functions on the sphere based on covariance functions in R 3 . We also provide theorems that specify the conditions under which the resulting correlation function is isotropic or axially symmetric. For large datasets on the sphere commonly seen in modern applications, the Vecchia approximation is used to achieve higher scalability on statistical inference. The importance of flexible covariance structures is demonstrated numerically using simulated data and a precipitation dataset. Supplementary materials accompanying this paper appear online. [ABSTRACT FROM AUTHOR]

Recently, we have successfully achieved the atmospheric pressure catalytic synthesis of nanodiamonds by applying high stress to Ti3C2/Ni composite and then performing chlorine gas etching at atmospheric pressure. In this work, we chose three different catalysts (Fe, Co and Ni), with Ti3C2 as the precursor, aiming to investigate the effect of catalyst type on the synthesis of NDs. The results show that all three catalysts can catalyze the synthesis of NDs and that the crystal type and plasticity of the catalysts may have an important effect on the type and size of the resulting ND. When Fe and Ni were used as catalysts, the percentage of C-type NDs obtained was higher than that of C-type NDs catalyzed by Co (hexagonal close-packed crystal structure) due to its face-centered cubic crystal structure. In contrast, more H-type NDs were catalytically synthesized when Co (hexagonal close-packed crystal structure) was used as the catalyst. In addition, the number of small-size NDs (< 10 nm) catalytically synthesized by Co was significantly more than that catalytically synthesized by Fe and Ni, this may be caused by the poor plasticity of Co with a hexagonal close-packed crystal structure compared to Fe and Ni with a face-centered cubic crystal structure. [ABSTRACT FROM AUTHOR]

Automating retrosynthesis with artificial intelligence expedites organic chemistry research in digital laboratories. However, most existing deep-learning approaches are hard to explain, like a "black box" with few insights. Here, we propose RetroExplainer, formulizing the retrosynthesis task into a molecular assembly process, containing several retrosynthetic actions guided by deep learning. To guarantee a robust performance of our model, we propose three units: a multi-sense and multi-scale Graph Transformer, structure-aware contrastive learning, and dynamic adaptive multi-task learning. The results on 12 large-scale benchmark datasets demonstrate the effectiveness of RetroExplainer, which outperforms the state-of-the-art single-step retrosynthesis approaches. In addition, the molecular assembly process renders our model with good interpretability, allowing for transparent decision-making and quantitative attribution. When extended to multi-step retrosynthesis planning, RetroExplainer has identified 101 pathways, in which 86.9% of the single reactions correspond to those already reported in the literature. As a result, RetroExplainer is expected to offer valuable insights for reliable, high-throughput, and high-quality organic synthesis in drug development. Automating retrosynthesis prediction in organic chemistry is a major application of ML. Here the authors present RetroExplainer, which offers a high-performance, transparent and interpretable deep-learning framework providing valuable insights for drug development. [ABSTRACT FROM AUTHOR]

Maintaining a healthy status is crucial for the successful captive breeding of endangered alpine musk deer (Moschus chrysogaster, AMD), and captive breeding programs are beneficial to the ex-situ conservation and wild population recovery of this species. Meanwhile, the gut microbiota is essential for host health, survival, and environmental adaptation. However, changes in feeding environment and food can affect the composition and function of gut microbiota in musk deer, ultimately impacting their health and adaptation. Therefore, regulating the health status of wild and captive AMD through a non-invasive method that targets gut microbiota is a promising approach. Here, 16S rRNA gene sequencing was employed to reveal the composition and functional variations between wild (N = 23) and captive (N = 25) AMD populations. The results indicated that the gut microbiota of wild AMD exhibited significantly higher alpha diversity (P < 0.001) and greater abundance of the phylum Firmicutes, as well as several dominant genera, including UCG-005, Christensenellaceae R7 group, Monoglobus, Ruminococcus, and Roseburia (P < 0.05), compared to captive AMD. These findings suggest that the wild AMD may possess more effective nutrient absorption and utilization, a more stable intestinal microecology, and better adaption to the complex natural environment. The captive individuals displayed higher metabolic functions with an increased abundance of the phylum Bacteroidetes and certain dominant genera, including Bacteroides, Rikenellaceae RC9 gut group, NK4A214 group, and Alistipes (P < 0.05), which contributed to the metabolic activities of various nutrients. Furthermore, captive AMD showed a higher level of 11 potential opportunistic pathogens and a greater enrichment of disease-related functions compared to wild AMD, indicating that wild musk deer have a lower risk of intestinal diseases and more stable intestinal structure in comparison to captive populations. These findings can serve as a valuable theoretical foundation for promoting the healthy breeding of musk deer and as a guide for evaluating the health of wild-released and reintroduced musk deer in the future. Key points: • Wild and captive AMD exhibit contrasting gut microbial diversity and certain functions. • With higher diversity, certain bacteria aid wild AMD's adaptation to complex habitats. • Higher potential pathogens and functions increase disease risk in captive AMD. [ABSTRACT FROM AUTHOR]

Coated carbide tools are widely used in the processing of nickel-based superalloys due to their excellent wear resistance, high strength, and good hardness at high temperatures. In this paper, the high-speed milling experiments and finite element simulation of Inconel 718 are carried out by using PVD TiAlN-coated carbide tools. Simulations of tool temperature, cutting force, and chip morphology were performed to analyze the effect of cutting speed on the degree of sawtooth chip formation and the effect of sawtooth chip formation on the cutting force and tool wear. The results show that the cutting temperature mainly focuses on the rake face, and with the cutting speed increasing from 60 to 120 m/min, the maximum temperature of the rake face increases from 580 to 660 ℃. The maximum temperature region (MTR) on the rake face gradually approaches the tool nose with a decrease in the cutting speed. The generation of sawtooth chips leads to fluctuations in the cutting force component. As the cutting speed increases, the degree of chip sawing increases. The effect of the sawtooth chip on the fluctuation of the cutting force will also increase, thus increasing the degree of tool wear. [ABSTRACT FROM AUTHOR]

Background: The miRNA profile is changed after burn or sepsis and is involved in regulating inflammatory reactions. However, the function and molecular mechanism of miRNAs in regulating burn sepsis-induced acute kidney injury (AKI) are still unclear. Methods: In this study, animal and cell sepsis models were established after burned rats were injected with lipopolysaccharide (LPS) or NRK-52E cells treated with LPS, respectively. Cytokine expression, inflammatory cell infiltration, serum creatinine (Scr) and kidney injury molecule-1 (KIM-1) levels were analysed after the indicated treatments. Results: Burn sepsis increased the expression of inflammatory factors (TNF-α and IL-1β) and chemokines (MIP-1α, MIP-2 and MCP-1). Moreover, burn sepsis promoted macrophage and neutrophil infiltration into the kidney and upregulated the levels of Scr and KIM-1 in the kidney and urine. Ectopic expression of miR-181c significantly reduced LPS-induced TLR4 protein expression, suppressed KIM-1 mRNA levels and subsequently inhibited the activation of inflammatory genes (TNF-α and IL-1β) and chemokine genes (MIP-1α, MIP-2 and MCP-1). Conclusions: Our results demonstrated that miR-181c could suppress TLR4 expression, reduce inflammatory factor and chemokine secretion, mitigate inflammatory cell infiltration into the kidney and downregulate KIM-1 expression, which might ultimately attenuate burn sepsis-induced AKI. [ABSTRACT FROM AUTHOR]

The machinability and wear reduction mechanism of self-repairing and self-lubricating ceramic tools sintered by vacuum hot-pressing method in the dry turning of 40Cr hardened steel was studied. By comparing the cutting performance and wear morphology of AT (Al2O3/TiC) ceramic tools under different cutting parameters, it was found that AT10B@5 (Al2O3/TiC/10 vol% TiB2/5 vol% h-BN@Al2O3) tool has a longer service life and better machining quality. Owing to the precipitation of solid lubricant during the cutting of AT10B@5 ceramic tool, the friction force during the cutting is reduced, thus decreasing the cutting force and cutting temperature of AT10B@5 ceramic tool during the cutting. The main cutting force decreased by 20.8%; the cutting temperature decreased by 22.2%; and the friction coefficient of front tool face decreased by 11.6% compared with AT tool. This effectively improved the surface quality of working parts, reduced the tool wear, increased the processing quality of work piece, and prolonged the tool life. [ABSTRACT FROM AUTHOR]

A new type of Mo@Ni reinforcement (W,Ti)C cermet was prepared by spark plasma sintering. The solution strengthening mechanism of the Mo@Ni reinforcement (W,Ti)C cermet was investigated. The results showed that proper holding time and sintering pressure could achieve a solid solution between the metal and ceramic phases. Under a sintering temperature of 1325 °C and a heating rate of 400 °C/min, the optimal holding time and sintering pressure of the (W,Ti)C cermet were 10 min and 20 MPa, respectively. Under these conditions, the flexural strength, fracture toughness, and Vickers hardness of the material reached 1550 ± 34 MPa, 12.35 ± 0.31 MPa m1/2, and 17.54 ± 0.33 GPa, respectively. The formation of a braided structure at the grain boundary increased the grain boundary strength and the bond strength between the grains; additionally, it increased the relative density, decreased the microstructure flaws, and made the grain size of the material fine and homogeneous. [ABSTRACT FROM AUTHOR]

Isodon amethystoides (Lamiaceae) is a popular plant in folk medicine in the southern provinces of China. Our phytochemical investigation of the twigs and leaves of this plant led to the discovery of five new diterpenoids with isopimarane and 3,4-seco isopimarane scaffolds [isoamethinols A–E (1–5)], along with the known compound 3,4-seco isopimara-4(18),7,15-triene-3-oic acid methylester (6). The chemical structures of these compounds, including the absolute configurations of the new diterpenoids, were determined by comprehensive spectroscopic analyses and single crystal X-ray diffraction measurements. These compounds were evaluated for their biological activities against a panel of human cancer cell lines, gram-positive bacterial strains and HIV. Notably, the 3,4-seco-isopimarane isoamethinol D (4) showed toxicity to the cervical Hela cancer (Hela) cells with an IC50 value of 27.21 μM and the lung (A549) cancer cells with an IC50 value of 21.47 μM. Compound 4 also exhibited mild antimicrobial activity against the oral bacterial strain Streptococcus mutans. These findings suggested that the diterpenoids with a 3,4-seco-isopimarane diterpenoids isolated from I. amethystoides could provide a novel structure scaffold for the discovery of anticancer and antimicrobial compounds. [ABSTRACT FROM AUTHOR]

Gaussian processes (GPs) are popular models for functions, time series, and spatial fields, but direct application of GPs is computationally infeasible for large datasets. We propose a multi-scale Vecchia (MSV) approximation of GPs for modeling and analysis of multi-scale phenomena, which are ubiquitous in geophysical and other applications. In the MSV approach, increasingly large sets of variables capture increasingly small scales of spatial variation, to obtain an accurate approximation of the spatial dependence from very large to very fine scales. For a given set of observations, the MSV approach decomposes the data into different scales, which can be visualized to obtain insights into the underlying processes. We explore properties of the MSV approximation and propose an algorithm for automatic choice of the tuning parameters. We provide comparisons to existing approaches based on simulated data and using satellite measurements of land-surface temperature. [ABSTRACT FROM AUTHOR]

Introduction: To explore the impact of coronavirus disease 2019 (COVID-19) on the stability of patients with neovascular age-related macular degeneration (nAMD) receiving the treat and extend (T&E) or the pro re nata (PRN) treatment regimen and to identify indicators that may predict the disease stability of nAMD. Methods: This is a retrospective study of patients with nAMD treated at the Second Affiliated Hospital of Harbin Medical University whose treatment schedule was interrupted at least once between 1 February and 31 May 2020. The demographic and clinical characteristics, including the best corrected visual acuity (BCVA), optical coherence tomography (OCT) features, subfoveal choroidal thickness (SFCT), interval between the last injection and the beginning of the pandemic, and the number of anti-vascular endothelial growth factor (VEGF) injections, were analyzed. Results: A total of 209 stable patients with nAMD (122 eyes received the T&E regimen; 87 eyes received the PRN regimen) were identified. Compared to those who received the PRN regimen, the patients who received the T&E regimen were more stable during the first visit after COVID-19 (53.3% vs. 33.3%, P = 0.004), the BCVA was significantly better (58.5 letters vs. 56 letters, P = 0.006), and the CRT fluctuated only slightly (15 μm vs. 35 μm, P = 0.001). Furthermore, a multivariate logistic regression analysis showed that stable patients with nAMD with type 1 choroidal neovascularization (CNV) (OR 2.493 [95% CI 1.179–5.272], compared with type 2 CNV; P = 0.017; OR 2.912 [95% CI 1.133–7.485], compared with retinal angiomatous proliferation; P = 0.026) or with pigment epithelial detachment (PED) were more likely to remain stable when treatment was interrupted (OR 0.392 [95% CI 0.181–0.852], compared with no PED; P = 0.018). Conclusion: Compared to patients who received the PRN treatment regimen, stable patients with nAMD who received the T&E treatment regimen could better maintain stability when the treatments were suddenly interrupted by the COVID-19 pandemic. In addition, patients with type 1 CNV or patients with PED were more likely to remain stable. At present, the COVID-19 pandemic is becoming increasingly normalized, and the T&E regimen can become a more advanced treatment option for patients undergoing therapy. [ABSTRACT FROM AUTHOR]

Syntactic foams with high strength and light weight are essential for aerospace and deep sea explorations. In this study, high-performance carbon fiber/hollow glass microspheres/epoxy syntactic foams were prepared, and the reinforcing mechanism of carbon fiber is discussed. The syntactic foam with 3 wt% short carbon fiber achieves a uniaxial compressive strength of 141.7 MPa, which is among the highest values reported in the literature. The thermal conductivity of syntactic foam increased by 66.7% with the addition of 3 wt% short carbon fibers, which helped to control the cracking issue caused by the inner temperature surge during the curing process. Further stress characterizations using fiber Bragg gratings (FBGs) confirmed that carbon fiber can relieve the evolution of thermal stress and reduce the residual thermal stress. [ABSTRACT FROM AUTHOR]

Gut microbiota forms a unique microecosystem and performs various irreplaceable metabolic functions for ruminants. The gut microbiota is important for host health and provides new insight into endangered species conservation. Forest musk deer (FMD) and alpine musk deer (AMD) are typical small ruminants, globally endangered due to excessive hunting and habitat loss. Although nearly 60 years of captive musk deer breeding has reduced the hunting pressure in the wild, fatal gastrointestinal diseases restrict the growth of captive populations. In this study, 16S rRNA high-throughput sequencing revealed the differences in gut microbiota between FMD and AMD based on 166 fecal samples. The alpha diversity was higher in FMD than in AMD, probably helping FMD adapt to different and wider habitats. The ß-diversity was higher between adult FMD and AMD than juveniles and in winter than late spring. The phylum Firmicutes and the genera Christensenellaceae R7 group, Ruminococcus, Prevotellaceae UCG-004, and Monoglobus were significantly higher in abundance in FMD than in AMD. However, the phylum Bacteroidetes and genera Bacteroides, UCG-005, Rikenellaceae RC9 gut group, and Alistipes were significantly higher in AMD than FMD. The expression of metabolic functions was higher in AMD than in FMD, a beneficial pattern for AMD to maintain higher energy and substance metabolism. Captive AMD may be at higher risk of intestinal diseases than FMD, with higher relative abundances of most opportunistic pathogens and the expression of disease-related functions. These results provide valuable data for breeding healthy captive musk deer and assessing their adaptability in the wild. Key points: • Alpha diversity of gut microbiota was higher in FMD than that in AMD • Expression of metabolic and disease-related functions was higher in AMD than in FMD [ABSTRACT FROM AUTHOR]

DLC has been applied as coating material in the machining of difficult-to-cut materials, and shows a good cutting performance. In this study, Cr/W-DLC/DLC-coated tools were compared with other three kinds of coated tools (TiC-, TiAlN-, Al2O3-) to investigate the cutting performance in the machining of Al–Si alloy. The influence of Cr/W-DLC/DLC-coated tools on the cutting performance under different cutting speeds was studied. Cutting force, cutting temperature, heat partition coefficient, cutting deformation rate, plastic deformation of machined surface, the interface temperature, and stress were investigated numerically with the aid of finite element method (FEM). Actual cutting experiments were carried out to verify the FEM models by means of the cutting force and cutting temperature measurement. The investigation results show that Cr/W-DLC/DLC-coated tool had the best cutting performance among these four kinds of coated tools. With the increasing of cutting speeds, cutting force and cutting temperature showed an increase trend, while the plastic deformation depth of machined surface and heat partition into cutting tool all showed a decrease trend during the machining with Cr/W-DLC/DLC-coated tool. This investigation can provide the theory basis or technical guidance for the cutting practice with Cr/W-DLC/DLC-coated tools. [ABSTRACT FROM AUTHOR]

The coating effect on the cutting temperature has long been a hot topic in understanding heat transfer mechanism in machining coated tools, and especially the multi-layer coated tools. For multi-layer coated tools, the coating structure, coating thickness, and coating material will affect the cutting temperature of the tools. This paper is devoted to the cutting temperature in dry turning of H13 hardened steel with multi-layer coatings. New analytical models for estimating coating temperature and coating–substrate interface temperature were proposed. The multi-layer coating can be equivalent to mono-layer composite coating, which applies equivalent coating layer approach, and was developed to estimate the cutting temperature in turning by heat transfer model of mono-layer coated tool. The analyzed results were compared with appropriate experimental process data using thermocouples and FEM simulated data. The models can accurately reflect the cutting temperature of two multi-layer coated tools under the same cutting condition. [ABSTRACT FROM AUTHOR]

Tool wear damages the surface quality of the workpiece and increases equipment downtime. Tool wear prediction is of great importance for reducing processing costs and improving processing efficiency. This paper applies multisensor fusion technology to predict tool wear. The cutting force, vibration, and acoustic emission signals are collected simultaneously during the milling process. The time domain, frequency domain, and time–frequency domain characteristics of each signal are extracted, reduced, and filtered through correlation analysis. A GSA-BP prediction model is established by a BP neural network in which the weights and thresholds are optimized through the gravitational search algorithm (GSA). The test results show that the prediction results of the GSA-BP model are in good agreement with the actual wear, and the prediction accuracy is higher than that of the traditional BP neural network model. [ABSTRACT FROM AUTHOR]

Cigarette smoking is the major cause of chronic obstructive pulmonary disease. Considerable attention has been paid to the reduced harm potential of nicotine-containing inhalable products such as electronic cigarettes (e-cigarettes). We investigated the effects of mainstream cigarette smoke (CS) and e-vapor aerosols (containing nicotine and flavor) generated by a capillary aerosol generator on emphysematous changes, lung function, and molecular alterations in the respiratory system of female Apoe−/− mice. Mice were exposed daily (3 h/day, 5 days/week) for 6 months to aerosols from three different e-vapor formulations—(1) carrier (propylene glycol and vegetable glycerol), (2) base (carrier and nicotine), or (3) test (base and flavor)—or to CS from 3R4F reference cigarettes. The CS and base/test aerosol concentrations were matched at 35 µg nicotine/L. CS exposure, but not e-vapor exposure, led to impairment of lung function (pressure–volume loop area, A and K parameters, quasi-static elastance and compliance) and caused marked lung inflammation and emphysematous changes, which were confirmed histopathologically and morphometrically. CS exposure caused lung transcriptome (activation of oxidative stress and inflammatory responses), lipidome, and proteome dysregulation and changes in DNA methylation; in contrast, these effects were substantially reduced in response to the e-vapor aerosol exposure. Compared with sham, aerosol exposure (carrier, base, and test) caused a slight impact on lung inflammation and epithelia irritation. Our results demonstrated that, in comparison with CS, e-vapor aerosols induced substantially lower biological and pathological changes in the respiratory tract associated with chronic inflammation and emphysema. [ABSTRACT FROM AUTHOR]

Subtractive machining is required for laser cladded coatings to improve surface quality. However, cutting force performs distinctively due to the coarse profile and structural properties of the laser cladded coatings. The coarse profile of the laser cladded coatings resulted in variable depth of cut in rough turning, while the vibration caused the fluctuations of cutting force in finish turning. In this research, the cutting force characteristics in remanufacturing turning of the laser cladded coatings are investigated. Firstly, cutting force model was established by considering the coarse profile as well as cutting vibration. The experimental results further confirmed that the presented model could predict the cutting forces in remanufacturing processes. Secondly, the effects of the coarse profile and cutting vibration on cutting forces were analyzed based on the presented model. The rough profile is prone to cause tool breakage in rough turning, while the cutting vibration generated great influence on radial force component in finish turning. The results suggested that the rough turning needed to be divided into multiple passes for peeling-off, and the stiffness should be enhanced to reduce cutting vibration in finish turning. [ABSTRACT FROM AUTHOR]

Liquid hydrogen (LH2) attracts widespread attention because of its highest energy storage density. However, evaporation loss is a serious problem in LH2 storage due to the low boiling point (20 K). Efficient insulation technology is an important issue in the study of LH2 storage. Hollow glass microspheres (HGMs) is a potential promising thermal insulation material because of its low apparent thermal conductivity, fast installation (Compared with multi-layer insulation, it can be injected in a short time.), and easy maintenance. A novel cryogenic insulation system consisting of HGMs and a self-evaporating vapor-cooled shield (VCS) is proposed for storage of LH2. A thermodynamic model has been established to analyze the coupled heat transfer characteristics of HGMs and VCS in the composite insulation system. The results show that the combination of HGMs and VCS can effectively reduce heat flux into the LH2 tank. With the increase of VCS number from 1 to 3, the minimum heat flux through HGMs decreases by 57.36%, 65.29%, and 68.21%, respectively. Another significant advantage of HGMs is that their thermal insulation properties are not sensitive to ambient vacuum change. When ambient vacuum rises from 10−3 Pa to 1 Pa, the heat flux into the LH2 tank increases by approximately 20%. When the vacuum rises from 10−3 Pa to 100 Pa, the combination of VCS and HGMs reduces the heat flux into the tank by 58.08%–69.84% compared with pure HGMs. [ABSTRACT FROM AUTHOR]

Background: Triple-negative breast cancer (TNBC) remains a great challenge in clinical treatment due to a shortage of effective therapeutic targets and acquired chemoresistance. Here, we identified the role of an RNA-binding protein, CUG-BP Elav-like family member 6 (CELF6), in the TNBC development and paclitaxel (PTX) chemoresistance. Methods: Stable CELF6-overexpressing cell lines were established in BT549 and MDA-MB-231 cells. Cell proliferation was determined using cell counting, two-dimensional colony formation, and MTT assay. Meanwhile, cell migration and cell invasion were detected by Transwell assay. Furthermore, the downstream target gene of CELF6 was identified and the direct interaction was further determined by luciferase reporter assay, immunoprecipitation, and RNA pull-down. Additionally, the PTX resistant cell line was established to determine the role of CELF6 in PTX resistance. Results: CELF6 overexpression suppressed cell proliferation, cell migration, and cell invasion. Mechanistically, Fructose-Bisphosphatase 1 (FBP1) was identified as the target gene of CELF6 and stabilized by CELF6 via binding 3′UTR. CELF6 overexpression mediated inhibition in TNBC development was dependent on FBP1. Moreover, CELF6 overexpression increased the sensitivity to PTX treatment. Conclusion: CELF6 functions as a tumor suppressor by upregulating FBP 1 expression via stabilizing its mRNA, and thereby inhibits TNBC progression. [ABSTRACT FROM AUTHOR]

In the paper, the achievements obtained from carrying out the policy of environmental protection price for promoting air pollution control in coal-fired power plants in China during more than a decade were summarized. Based on the situation of current electricity market reform, the role and effectiveness of environmental protection price for controlling the normal air pollutants, such as sulfur dioxide, nitrogen oxides, and dust in China's coal-fired power generation plants, were investigated, including the price structure of electricity environmental protection for coal-fired power generation enterprises in different regions, generating units, and power demands. The policy suggestions were proposed, namely, the reform of electricity environmental protection price would be carried out gradually, the relationship between electricity environmental protection price policy and other environmental protection policies would be matched under the relative overcapacity condition, and the environmental protection price regulation would be integrated into other environmental policies. [ABSTRACT FROM AUTHOR]

Since Dr. Carl Salomon proposed the well-known hypothesis on cutting temperatures in 1931, the debate on the hypothesis has never stopped. It shows that evolutions of temperatures with the increase of cutting speed measured at different points are different. From the tool wear and surface integrity point of view, this paper focuses on the evolutions of chip temperature (Chip temp.), tool-chip contact temperature (T-C temp.), and tool-workpiece contact temperature (T-W temp.) with the increase of cutting speed from low (100 m/min) to very high (7000 m/min). First, the cutting heat generation and the temperature increment in machining are theoretically analyzed. Then the influences of chip shape and mechanical property variations with the increase of cutting speed on the temperatures are analyzed. Finally, the cutting temperatures are semiquantitatively derived from chip colors and other heat characteristics in the chip and cutting tool obtained in cutting experiments: evolutions of Chip temp., T-C temp., and T-W temp. with the increase of cutting speed are presented based on the experiment results. The influence of chip shape and temperature variation on tool wear are also discussed. [ABSTRACT FROM AUTHOR]

Diamond-like carbon (DLC)-coated tools are suitable for the machining of various aluminum alloys, graphite, and other non-ferrous metals. The shortcomings of DLC-coated tools such as high internal residual stress, low toughness, and poor adhesion strength limit their application. In order to reveal the mechanical and cutting performance of DLC-coated tools, a DLC monolayer coating, Cr/CrN/DLC composite coating, and Cr/W-DLC/DLC composite coating had been prepared on the cemented carbide cutting tools. The influences of transition interlayer on the microstructure and mechanical properties of DLC coatings were analyzed. Tool lives, wear mechanism, and machined surface roughness obtained with uncoated cemented carbide tool, DLC monolayer–coated tool, and Cr/x/DLC-coated tool during the machining of Al-Si alloys were investigated. Compared with DLC monolayer coating, the strength ratio (ID/IG) of the DLC composite coatings with Cr/x transition structure was improved, while the sp3 covalent bond contents was decreased. The results show that the adhesion strength and toughness of the Cr/x/DLC composite coating were enhanced, and the residual stress was greatly reduced. The cutting tests further indicate that the DLC coating significantly improved the tool life. Based on comprehensive evaluation, the Cr/W-DLC/DLC composite coating has the highest adhesion, highest toughness, the lowest residual stress, and the longest tool life, and it is suitable for the machining of non-ferrous metal. [ABSTRACT FROM AUTHOR]

Background: Anorectal malformation (ARM) is known to be associated with maldevelopment of the enteric nervous system (ENS), and vitamin A (VA) and its metabolite retinoic acid (RA) play important roles in ENS development. Thus, our aim was to investigate serum VA levels in ARM newborns and RA receptor (RAR) expression in the rectum of ARM patients and animal models.Methods: Serum VA concentrations were detected in newly diagnosed ARM neonates (n = 32) and neonates with non-alimentary tract malformations (n = 30). Intestinal specimens were divided into three groups: rectum from ARM patients (n = 30), colon from a stoma (n = 30) and rectum from controls (n = 4). RAR mRNA expression was evaluated by RT-qPCR. Rectum specimens from ARM patients were divided into two groups by postoperative pathology: the normal and lesion ganglion cell groups. Immunohistochemistry and Western blot were employed to detect RARα protein expression in rectum specimens. In addition, the ARM mouse model was induced by all-trans retinoid acid (ATRA), and the expression levels of RARα and the neuronal marker NeuN in the rectum of mice on embryonic day 16.5-18.5 (E16.5-18.5) were investigated.Results: The serum concentration of VA in ARM neonates was lower than that in control neonates (P < 0.0001), and RARα mRNA expression was lower in the rectum specimens from ARM patients than in the colon specimens from a stoma and the rectum specimens from controls (P < 0.05); there was no significant difference between the colon from a stoma and the rectum from controls. RARα protein was expressed in the nucleus of ganglion cells and nerve fibers, and RARα protein expression in the lesion ganglion cell group was significantly lower than that in the normal ganglion cell group (P < 0.01). Compared with the control mice, ARM mice at E16.5-18.5 showed decreased fluorescence intensity of RARα and NeuN in the rectum. RARα and NeuN mRNA expression in the rectum on E16.5-18.5 was lower in ARM mice than in control mice (P < 0.05).Conclusion: Serum VA concentration and the RARα expression pattern are abnormal in the rectum in ARM and may contribute to the ENS maldevelopment in ARM. [ABSTRACT FROM AUTHOR]

Lots of heat generated in the cutting deformation zone can cause the temperature rising of cutting tool and workpiece during the cutting process. Tool temperature is mainly depended on the heat energy entering into tool in the secondary deformation zone. Higher working temperature can weaken the cutting tool strength and then deteriorate the tool wear. Advanced coating layer deposited on the tool substrate can change the tool-chip friction and affect the heat partition in the tool-chip interface. In order to reveal the mechanism of heat conduction in the secondary deformation zone, the model of heat partition into cutting tool was built. With the aid of finite element method (FEM), the relative parameters which were necessary for the solving of heat partition model were quantified. Actual cutting experiments were carried out to the verification of the FEM models by means of the cutting force and temperature measurement. Influences of coatings (i.e., coating materials, coating thickness) and cutting speeds on the heat partition were analyzed. And then, rake face temperatures obtained at four kinds of coated tools were compared. The investigation results showed that TiC coating appears as the maximum value and Al2O3 coating appears as the minimum value of heat partition coefficient into cutting tool among these four kinds of coatings (i.e., TiC, TiN, TiAlN, Al2O3). With the increasing of coating thickness and cutting speeds, heat partition into cutting tool all showed a decrease trend. Al2O3-coated tool had the maximum rake face temperature among these four kinds of coated tools; however, the location of peak temperature on the rake face of Al2O3-coated tool was the shortest distance from the tool tip. [ABSTRACT FROM AUTHOR]

The temperature distribution in monolayer-coated cutting tools is calculated with heat conduction model established based on non-Fourier law and obtained using Laplace transform. A number of different coating materials, starting from uncoated up to three coatings (TiN, TiC, AlO), in combination with the carbide, are calculated. Simulated cutting experiments are carried out to verify the temperature of this heat conduction model. An infrared camera attached on the fixture is used to research the heat conduction behavior on the rake face along coating thickness of cutting. The study results demonstrate that the calculated temperature shows a similar trend as the measured temperature when it is analyzed along the coating thickness direction. Coated tools are more effective than uncoated tools in diminishing temperatures during cutting. AlO coating has better thermal barrier effect than TiN and TiC coatings. [ABSTRACT FROM AUTHOR]

Coated cutting tools have been widely employed in metal cutting operations owing to its excellent abrasion resistance and heat transfer performances. Rake face temperature is the primary factor that determines the temperature distribution in the cutting tool body. Based on the heat source theory, a new prediction model is proposed in this paper to forecast the temperature distribution on the rake face. Infrared image is used to develop a new turning experimental apparatus to measure the rake face temperature of coated tool during the cutting process. Rake face temperature measurement results are used to verify the proposed model prediction results of temperature distribution. Several cutting tests are carried out with monolayer coated tools in the machining of H13 hardened steel. The rake face temperature in monolayer coated tool for machining H13 shows an increase trend as the cutting speed increases. The influence parameters including thermo-physical properties and tool/workpiece frictional coefficient of coating material on temperature distribution in coated tools are discussed and illustrated. The research results presented in this paper can help to access the potential of coated tools used in the hardened steel machining. [ABSTRACT FROM AUTHOR]

Graphs are used to model many real objects such as social networks and web graphs. Many real applications in various fields require efficient and effective management of large-scale, graph-structured data. Although distributed graph engines such as GBase and Pregel handle billion-scale graphs, users need to be skilled at managing and tuning a distributed system in a cluster, which is a non-trivial job for ordinary users. Furthermore, these distributed systems need many machines in a cluster in order to provide reasonable performance. Several recent works proposed non-distributed graph processing platforms as complements to distributed platforms. In fact, efficient non-distributed platforms require less hardware resource and can achieve better energy efficiency than distributed ones. GraphChi is a representative non-distributed platform that is disk-based and can process billions of edges on CPUs in a single PC. However, the design drawbacks of GraphChi on I/O and computation model have limited its parallelism and performance. In this paper, we propose a general, disk-based graph engine called gGraph to process billion-scale graphs efficiently by utilizing both CPUs and GPUs in a single PC. GGraph exploits full parallelism and full overlap of computation and I/O processing as much as possible. Experiment results show that gGraph outperforms GraphChi and PowerGraph. In addition, gGraph achieves the best energy efficiency among all evaluated platforms. [ABSTRACT FROM AUTHOR]

An algorithm combined with back propagation neural network (BPNN) and genetic algorithm (GA) was used in the optimum design of the compositions of an advanced ZrO/TiB/AlO nano-micro-composite ceramic tool and die materials. GA was used to fully optimize the network topology, thresholds, and initial connection weights of BPNN. The input parameters are the contents of each compositions of ceramic tool and die materials and the output parameters are mechanical properties including hardness, flexural strength, and fracture toughness. The compositions with optimum mechanical properties can be chosen for materials preparation with less error and the result can be used to guide the experimental process. As a result, the nano-micro-composite ceramic tool and die material with good mechanical properties was then fabricated. It indicated that the algorithm can offer a robust and efficient way for the compositional design of ceramic tool and die materials. [ABSTRACT FROM AUTHOR]

The aim of the present work was to investigate in detail the influence of running-in with acetylacetone on the friction behavior of 5CB liquid crystal between steel surfaces. Friction tests were carried out using a sliding ball-on-disk tribometer. The coefficient of friction (COF) decreased significantly after a running-in process with acetylacetone. Tribochemical reactions between steel and acetylacetone generated Fe(acac)3 and groove-structured wear on the ball. Their synergistic effect is the reason for the ultralow friction, and without either one, the COF increases. Special attention was given to the rheological behavior of 5CB. Shear history has a significant influence on the viscosity and storage moduli of 5CB. In addition, the COF under the same low speed decreased by 37% after a friction test at higher speed. The possible mechanism is discussed, and an in-depth understanding of this tribological system is needed to develop possible future applications. [ABSTRACT FROM AUTHOR]

To investigate the neural mechanisms underlying attention deficits that are related to neoadjuvant chemotherapy in combination with cerebral perfusion. Thirty one patients with breast cancer who were scheduled to receive neoadjuvant chemotherapy and 34 healthy control subjects were included. The patients completed two assessments of the attention network tasks (ANT), neuropsychological background tests, and the arterial spin labeling scan, which were performed before neoadjuvant chemotherapy and after completing chemotherapy. After neoadjuvant chemotherapy, the patients exhibited reduced performance in the alerting and executive control attention networks but not the orienting network (p < 0.05) and showed significant increases in cerebral blood flow (CBF) in the left posterior cingulate gyrus, left middle occipital gyrus, bilateral precentral gyrus, inferior parietal gyrus, supramarginal gyrus, angular gyrus, precuneus, cuneus, superior occipital gyrus, calcarine cortex, and temporal gyrus (p < 0.01 corrected) when compared with patients before chemotherapy and healthy controls. A significant correlation was found between the decrease performance of ANT and the increase in CBF changes in some brain regions of the patients with breast cancer. The results demonstrated that neoadjuvant chemotherapy influences hemodynamic activity in different brain areas through increasing cerebral perfusion, which reduces the attention abilities in breast cancer patients. [ABSTRACT FROM AUTHOR]

To improve the mechanical characteristics and machinability of Ti(C,N) cermet and broaden its application range, Al2O3@Ni core–shell powders with varying Ni concentrations were generated using the heterogeneous precipitation-thermal reduction method, and Al2O3@Ni core–shell powders-reinforced Ti(C,N) cermet was created using spark plasma sintering (SPS). The mechanical, microstructural, and sintering characteristics of Ti(C,N) cermet were examined using core–shell powders with varying Ni contents. Al2O3@Ni core–shell powders with appropriate Ni content may uniformly distribute Ni with magnetic solid characteristics in cermet materials, resulting in rapid and uniform discharge that increases interface bonding, improves sintering, and greatly improves overall mechanical qualities. After adding core–shell powders, the cutting force of the TA@30N cermet tool is reduced compared to the TA30N cermet tool, but the surface quality of the machined workpiece improves. The effective cutting distance of the TA@30N cermet tool on heat-treated 45# steel is 36,000 m, 33.33% greater than that of the homogeneous TA30N cermet tool. [ABSTRACT FROM AUTHOR]

Bjerkandera adusta can decompose polycyclic aromatic hydrocarbons including cellulose and lignin, but its roles in inhibiting plant pathogens are unclear. Here, the confrontation culture and greenhouse pot experiments were employed to study the control effect of B. adusta M1 on Fusarium graminearum and wheat scab. The results showed that B. adusta M1 fermentation broth (FB) inhibited the growth of F. graminearum, with an inhibition rate of 52.7-89.17%. FB had a significant control effect (72.14 ± 1.42%) on wheat scab, which was slightly lower than that of the chemical fungicide carbendazim (77.34 ± 1.76%). The growth rate was significantly higher in B. adusta M1 than in F. graminearum, indicating a strong competitiveness by B. adusta M1. The images from a scanning electron microscope showed substantial deformations of the hyphae of F. graminearum being penetrated by the hyphae of B. adusta M1, indicating a strong mycoparasitism by B. adusta M1. In addition, FB increased the activity of catalase, peroxidase, and phenylalanine ammonia-lyase in wheat leaves related to disease resistance and decreased the malondialdehyde production and cell membrane permeability. We conclude that B. adusta M1 is a promising fungal agent to control the detriment of F. graminearum to cereal growth in the field., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)