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Residual stresses, related distortions and cracks are detrimental in metallic Additive Manufacturing (AM). Previously developed stress-control strategies based on reducing thermal gradients hardly diminish the stress concentrations at the built basement and easily affect other physical phenomena involved in AM. To overcome this, a novel strategy, named as Smart-Substrate, consisting of optimising the inner structure and local stiffness of the substrate is proposed to avert stress accretion and related part deformations. To demonstrate its advantages, a coupled thermomechanical finite element model for AM, experimentally calibrated with in-situ temperature and displacement measurements, is employed to analyse the thermal and mechanical behaviour of three groups of different structures with increasing geometrical complexity (single-wall, rectangular and block parts) fabricated by Directed Energy Deposit (DED) on the standard and smart substrates, respectively. Through using Smart-Substrate, the generation of residual stresses, especially the stress concentrations at the bottom corner of DED-builds being highly sensitive to cracks, and the induced deflections, are fundamentally throttled, and contrariwise for the standard substrate. More importantly, the use of Smart-Substrate is almost without prejudice to the temperature field, metallurgy and resulting mechanical hardness. This provides a possibility for addressing different physical problems individually, enlarging the AM process window.

Hybrid rocket engines suffer from the restricted mechanical properties and low regression rates of current polymeric fuel grains. We propose a three-dimensional printed aluminium (Al) nested composite fuel grain with millimetre-scale lattice pores (referred to as Al-L). In this study, breathable Al blades with micrometer-scale interconnected pores (Al-B) and blades combining millimetre-scale and micrometer-scale pores (Al-B&L) are designed. The formation mechanisms, characteristics, and effects of the breathable blades are analysed in simulations, micro-computed tomography, and cyclic compression tests. The mechanical properties of the composite fuel grains are investigated numerically and in compression tests. Al-B has the highest Young’s modulus at more than 15 times that of a paraffin-based fuel grain and Al-B&L has the highest yield stress at 4 times that of the paraffin-based fuel grain. Referring to combustion properties, the regression rates of the Al-B and Al-B&L grains are respectively 63.3% and 58.2% greater than the regression rate of the paraffin-based fuel grain.

ABSTRACTReplicating SARS-CoV-2 has been shown to degrade HLA class I on target cells to evade the cytotoxic T-cell (CTL) response. HLA-I downregulation can be sensed by NK cells to unleash killer cell immunoglobulin-like receptor (KIR)-mediated self-inhibition by the cognate HLA-I ligands. Here, we investigated the impact of HLA and KIR genotypes and HLA-KIR combinations on COVID-19 outcome. We found that the peptide affinities of HLA alleles were not correlated with COVID-19 severity. The predicted poor binders for SARS-CoV-2 peptides belong to HLA-B subtypes that encode KIR ligands, including Bw4 and C1 (introduced by B*46:01), which have a small F pocket and cannot accommodate SARS-CoV-2 CTL epitopes. However, HLA-Bw4 weak binders were beneficial for COVID-19 outcome, and individuals lacking the HLA-Bw4 motif were at higher risk for serious illness from COVID-19. The presence of the HLA-Bw4 and KIR3DL1 combination had a 58.8% lower risk of developing severe COVID-19 (OR = 0.412, 95% CI = 0.187-0.904, p = 0.02). This suggests that HLA-Bw4 alleles that impair their ability to load SARS-CoV-2 peptides will become targets for NK-mediated destruction. Thus, we proposed that the synergistic responsiveness of CTLs and NK cells can efficiently control SARS-CoV-2 infection and replication, and NK-cell-mediated anti-SARS-CoV-2 immune responses being mostly involved in severe infection when the level of ORF8 is high enough to degrade HLA-I. The HLA-Bw4/KIR3DL1 genotype may be particularly important for East Asians undergoing COVID-19 who are enriched in HLA-Bw4-inhibitory KIR interactions and carry a high frequency of HLA-Bw4 alleles that bind poorly to coronavirus peptides.

ObjectivesTo investigate the current situation regarding occupational burnout among coal miners, explore the relationship between NR3C2 gene polymorphism and occupational burnout, and analyze the influence of the interaction between environment and gene on occupational burnout. This study provides a scientific basis for formulating health strategies to combat job burnout.MethodsA total of 1,500 first-line coal mine workers were selected by cluster random sampling, and the job burnout scale, job content questionnaire (JCQ), and simplified coping style questionnaire (SCSQ) were used for the questionnaire survey. A total of 150 workers were randomly selected from the high burnout group and the low burnout group, and a total of 300 workers were selected as the research objects to examine the relationship between gene polymorphism, environment-gene interactions and burnout. This study employed iMLDRTM genotyping technology for NR3C2 gene (rs5522, rs2070950) polymorphism analysis. The relationship between the occurrence of job burnout, occupational stress, coping styles and the NR3C2 gene was analyzed.ResultsFinally, a total of 1,282 valid questionnaires were retrieved, with an effective recovery rate of 85.5%. The study included 128 participants (10%) with zero burnout, 400 (31.2%) with mild burnout, 649 (50.6%) with moderate burnout and 105 (8.2%) with severe burnout. There were significant differences in the rate of burnout among miners with respect to sex, age, working years, educational level, shifts, and marital status (P < 0.05). The difference in occupational stress between the different job burnout groups was statistically significant (P < 0.05). Compared with the GG genotype of rs2070950 of the NR3C2 gene, the CC genotype was identified as a susceptibility gene for occupational burnout (P < 0.05). In respect to rs5522, rs2070950, occupational stress, positive coping, and negative coping, the low-risk group was unlikely to suffer from job burnout compared with the high-risk group (OR = 0.103, 95%CI: 0.058–0.182).ConclusionIn addition to demographic characteristics, occupational stress and negative coping styles were also identified as risk factors for job burnout. The interaction between locus rs5522, locus rs2070950, occupational stress, positive response, and negative response were found to affect the incidence of occupational burnout.

Abstract Predicting future land system changes driven by anthropogenic and climactic impacts can help to explore adaptation and mitigation pathways for regional and global sustainable development. Here, we project land cover changes in China from 2030 to 2100 at a resolution of 1 km × 1 km under eight scenarios based on the Scenario Model Intercomparison Project (ScenraioMIP), which are extracted from Land Use Harmonization version 2 (LUH2). We use a rule‐based method to classify and map 9 land cover dynamic trajectories at patch scale to present land system changes. At the provincial scale we used hierarchical clustering to identify archetypes of land cover change, which can predict ecological risks for future management in western provinces. Our results reveal that anthropogenic mitigation policies under high mitigation pressure do not result in positive impacts on the land system, but rising temperatures will provide a great opportunity for ecological restoration in some regions.

This paper addresses the performance and environmental impact evaluation of a developed UHPC with recycled mixed powder (RMP) and aeolian sand (AS). The RMP is obtained from the crushing and grinding of waste concrete blocks and clay bricks. The RMP and AS are used instead of cement and river sand during the UHPC's production. The macroperformance, hydration kinetics, microstructure development, and environmental impact of the newly produced UHPC are evaluated. The experimental results reveal that the effect and mechanism of RMP on the fluidity of UHPC are different from that of AS. The RMP and AS show a specific synergistic effect. The RMP can promote the initial hydration of the mixture but restricts its cumulative heat. The AS acts as a nucleation site to promote the secondary hydration reaction involving RMP. The ecological assessment demonstrates that the developed UHPC incorporating RMP and AS can reduce the burden on the environment.

Abstract The temperature distribution of the tri‐post insulator in a ±500 kV direct current gas‐insulated transmission lines (DC‐GIL) is investigated. The influence of thermal gradient on the electric field characteristics is investigated as well. A horizontally installed GIL model is applied in the simulation. The thermal and electric parameters of the insulator are measured and employed. The temperature results indicate that the gas shows a layered distribution pattern while the insulator shows a radial distribution pattern. The temperature of the upper post is higher. With increasing ambient temperature, the surface temperature increases linearly following the variation of ambient temperature. With increasing load current, the temperature near the conductor shows an obvious increase. With increasing gas pressure, the temperature decreases due to the promotion of convection. Besides, the electric field strength of the insulator surface increases if the surface temperature increases during the variation of operating conditions. And the peak of field strength moves towards the enclosure. After 10 h, the temperature reaches a quasi‐stationary state. Since the thermal gradient affects the distribution of gas density and electric field strength of the insulator, the investigation of temperature characteristics is necessary when evaluating the insulating performance of DC‐GIL with insulators.

Abstract Objective Oculopharyngeal muscular dystrophy (OPMD) is a late‐onset inherited neuromuscular disorder, with progressive ptosis and dysphagia as common manifestations. To date, OPMD has rarely been reported among East Asians. The present study summarizes the phenotypic and genotypic features of Chinese patients with OPMD. Methods Twenty‐one patients with molecularly confirmed OPMD from 9 unrelated families were identified by direct sequencing of the polyadenlyate binding protein nuclear‐1 (PABPN1) gene. Immunofluorescence staining of muscle biopsies was conducted to identify the components of protein degradation pathways involved in OPMD. Results In our cohort, the genetically confirmed OPMD group had a mean age at onset of 50.6 ± 4.2 years (range 45–60 years). Ptosis (42.9%) was the most common initial symptom; patients with ptosis as the first symptom subsequently developed dysphagia within a median time of 5.5 years (range 1–19 years). Evidence of external ophthalmoplegia was found in 38.1% of patients. A total of 33.3% of the patients developed muscle weakness at a median age at onset of 66 years (range 50–70 years), with neck flexor involvement in all patients. Five genotypes were observed in our cohort, including classical (GCG)9–11 repeats in 7 families and non‐GCG elongations with additional GCA expansions in 2 families. OPMD muscle biopsies revealed rimmed vacuoles and intranuclear filamentous inclusions. The PABPN1 protein showed substantial accumulation in the nuclei of muscle fiber aggregates and closely colocalized with p62, LC3B and FK2. Interpretation Our findings indicate wide genetic heterogeneity in OPMD in the Chinese population and demonstrate abnormalities in protein degradation pathways in this disease.

Abstract In recent years, convolutional neural networks (CNNs) have made great achievements in the field of medical image segmentation, especially full convolutional neural networks based on U-shaped structures and skip connections. However, limited by the inherent limitations of convolution, CNNs-based methods usually exhibit limitations in modeling long-range dependencies and are unable to extract large amounts of global contextual information, which deprives neural networks of the ability to adapt to different visual modalities. In this paper, we propose our own model, which is called iU-Net bacause its structure closely resembles the combination of i and U. iU-Net is a multiple encoder-decoder structure combining Swin Transformer and CNN. We use a hierarchical Swin Transformer structure with shifted windows as the primary encoder and convolution as the secondary encoder to complement the context information extracted by the primary encoder. To sufficiently fuse the feature information extracted from multiple encoders, we design a feature fusion module (W-FFM) based on wave function representation. Besides, a three branch up sampling method(Tri-Upsample) has developed to replace the patch expand in the Swin Transformer, which can effectively avoid the Checkerboard Artifacts caused by the patch expand. On the skin lesion region segmentation task, the segmentation performance of iU-Net is optimal, with Dice and Iou reaching 90.12% and 83.06%, respectively. To verify the generalization of iU-Net, we used the model trained on ISIC2018 dataset to test on PH2 dataset, and achieved 93.80% Dice and 88.74% IoU. On the lung feild segmentation task, the iU-Net achieved optimal results on IoU and Precision, reaching 98.54% and 94.35% respectively. Extensive experiments demonstrate the segmentation performance and generalization ability of iU-Net.

Abstract Background The fat mass and nutritional status play important roles in the onset and progression of cancer cachexia. The present study evaluated the joint prognostic value of the fat mass, as indicated by the triceps skinfold thickness (TSF), and the serum albumin level, for mortality in patients with cancer cachexia. Methods We performed a multicentre cohort study including 5134 patients with cancer cachexia from January 2013 to April 2019. The sum of the TSF (mm) and serum albumin (g/L) was defined as the triceps skinfold–albumin index (TA). Harrell's C index, a time‐dependent receiver operating characteristic (ROC) curve analysis and the area under the curve (AUC) were used to evaluate the prognostic performance of the TA and other indices. Optimal stratification was used to identify the thresholds to define a low TA, and the association of the TA with all‐cause mortality was evaluated using Kaplan–Meier analysis and Cox proportional hazard regression models. Results The study enrolled 2408 women and 2726 men with a median age of 58.6 years and a median follow‐up of 44 months. A total of 607 women (TA

The spatial transcriptome has enabled researchers to resolve transcriptome expression profiles while preserving information about cell location to better understand the complex biological processes that occur in organisms. Due to technical limitations, the current high-throughput spatial transcriptome sequencing methods (known as next-generation sequencing with spatial barcoding methods or spot-based methods) cannot achieve single-cell resolution. A single measurement site, called a spot, in these technologies frequently contains multiple cells of various types. Computational tools for determining the cellular composition of a spot have emerged as a way to break through these limitations. These tools are known as deconvolution tools. Recently, a couple of deconvolution tools based on different strategies have been developed and have shown promise in different aspects. The resulting single-cell resolution expression profiles and/or single-cell composition of spots will significantly affect downstream data mining; thus, it is crucial to choose a suitable deconvolution tool. In this review, we present a list of currently available tools for spatial transcriptome deconvolution, categorize them based on the strategies they employ, and explain their advantages and limitations in detail in order to guide the selection of these tools in future studies.

Sperm cryopreservation is an effective fertility preservation method for cancer patients before anticancer treatments. However, there are little data on fertility preservation in large cohorts of patients with cancer in southern China. This retrospective cross-sectional study aimed to assess the fertility preservation status of 1034 newly diagnosed male patients with cancer in the Human Sperm Bank of Guangdong Province in southern China (Guangzhou, China). Of these, 302 patients had reproductive system tumors, mostly testicular cancers (99.0%), and 732 had other tumors, including lymphoma (33.1%), gastrointestinal cancer (16.3%), nasopharyngeal carcinoma (15.7%), leukemia (7.7%), sarcoma (3.6%), and others (23.6%). Patients with reproductive system tumors had lower sperm concentration and prefreezing and post-thawing progressive motility than those with non-reproductive system tumors (all P < 0.001). Differences in sperm concentration, progressive motility, and normal morphology rate were observed between patients with and without anticancer surgery before sperm cryopreservation (all P < 0.05). As of April 30, 2022, 63 patients used their cryopreserved sperm for assisted reproductive technology treatments and 39 pregnancies were achieved. This study provides valuable data on the fertility preservation status in newly diagnosed cancer patients in southern China, demonstrating that patients with reproductive system tumors had poor sperm quality for their pretreatment fertility preservation.

Abstract Evolutionary multimodal optimization algorithms aim to provide multiple solutions simultaneously. Many studies have been conducted to design effective evolutionary algorithms for solving multimodal optimization problems. However, optimization problems with many global and acceptable local optima have not received much attention. This type of problem is undoubtedly challenging. In this study, we focus on problems with many optima, the so-called many-modal optimization problems, and this study is an extension of our previous conference work. First, a test suite including additively nonseparable many-modal optimization problems and partially additively separable many-modal optimization problems is designed. Second, an improved difficulty-based cooperative co-evolution algorithm (DBCC2) is proposed, which dynamically estimates the difficulties of subproblems and allocates the computational resources during the search. Experimental results show that DBCC2 has competitive performance.

On account of the enormous role of various government policies, it is very important and valuable to find remarkable independent variables from many practical factors of influencing American economy via choosing suitable methods and effective "optimal" models or equations. Based on the American economic data in practice, in order to creatively analyze and predict American economy under two different government policies, we analyze the relationship between each factor and the economy and obtain some greater impact factors to American gross domestic product (in short, GDP) by using a class of stepwise regression, and then we give optimal analysis and predict the influence to American GDP via employing support vector machine models. Further, we establish data comparison to provide beneficial reference for choosing from two different government policies. Finally, we propose some work for future research.

Abstract Objective The conventional breast Diffusion-weighted imaging (DWI) was subtly influenced by microcirculation owing to the insufficient selection of the b values. However, the multiparameter derived from multiple b-value exhibits more reliable image quality and maximize the diagnostic accuracy. We aim to evaluate the diagnostic performance of stand-alone parameter or in combination with multiparameter derived from multiple b-value DWI in differentiating malignant from benign breast lesions. Methods A total of forty-one patients diagnosed with benign breast tumor and thirty-eight patients with malignant breast tumor underwent DWI using thirteen b values and other MRI functional sequence at 3.0 T magnetic resonance. Data were accepted mono-exponential, bi-exponential, stretched-exponential, aquaporins (AQP) model analysis. A receiver operating characteristic curve (ROC) was used to evaluate the diagnostic performance of quantitative parameter or multiparametric combination. The Youden index, sensitivity and specificity were used to assess the optimal diagnostic model. T-test, logistic regression analysis, and Z-test were used. P value

The achievement of fine equiaxed β grain with conventional intragranular (α-Ti+β-Ti) microstructure in additive manufacturing titanium alloy remains a big challenge. We conquer this challenge by synergistically controlling β-grains during both solidification and subsequent thermal-cycles of laser directed energy deposition (DED), and a solution + quenching heat-treatment. Both the strength and plasticity of heat-treated Ti6Al4V3Ni0.05B are superior to those reported new DED titanium alloy and comparable to that of DED Ti6Al4V, because of the fine-equiaxed β-grains with intragranular (α-Ti+β-Ti) microstructure. These findings provide new insight into the grain structure control and the composition design of AM titanium alloy.