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Electron beam additive manufacturing (EBAM) has broad application prospects in the preparation of large structural components such as those in aerospace structures. It is of great significance to have a deep understanding of the residual stress distribution and deformation of EBAM. A three-dimensional transient thermal–mechanical coupling model was established for the comprehensive investigation of the deformation and residual stress of aluminum alloy components prepared by wire-feed EBAM for the first time. The reliability of the simulation model was verified by comparing the predicted temperature, stress and deformation with experimentally measured values. The influence of heat input on residual stress distribution and deformation was studied using the verified model. The simulation results indicate that reducing heat input is an efficient approach to reducing deformation and residual stress. The developed model can be a powerful tool to optimize process parameters to reduce the residual stress and deformation of EBAM aluminum alloy components. [ABSTRACT FROM AUTHOR]

Introduction: We aimed to carry out a retrospective study from a single institution to determine whether radioactive iodine (RAI) ablation decreases the risk of recurrence of papillary thyroid microcarcinoma (PTMC) patients that presented with lateral lymph node metastasis (LLNM). Methods: We retrospectively analyzed a total of 6361 consecutive PTMC patients who initially underwent surgery for the treatment of thyroid carcinoma at the First Hospital of Jilin University, between January 2005 and February 2015. Altogether, 137 patients with PTMC with LLNM have been enrolled in our study. Results: The disease-free survival period was significantly shorter for the RAI (−) patients than for the RAI (+) patients ( p = 0.0074 by the log-rank test). The disease-free survival rates at 5 and 10 years were 93.02 and 87.5%, respectively, in the RAI (−) group and 100 and 96.81%, respectively, in the RAI (+) group. CLNM ratio and LLNM ratio were factors identified for multivariate analysis by Cox's proportional hazards method yielding risk ratios of 7.281 [CI 1.804-17.554; p = 0.010] and 1.157 [CI 1.0125-9.381; p = 0.048] in the RAI (−) group. Conclusion: Taken together, RAI may be beneficial for PTMC with LLNM, especially when CLNM ratio or LLNM ratio was greater than 0.5. [ABSTRACT FROM AUTHOR]

The North Himalayan gneiss domes (NHGD), as one of the extensional structures widely distributed across the southern Tibetan Plateau, are an important window for studying post-collisional diastrophism and magmation as well as polymetallic mineralization. However, the deep mechanism for the formation of NHGD remains controversial. The magneto-telluric (MT) method was adopted to study the deep structure of the Cuonadong dome in the Northern Himalayas. The characteristics of the dome were explored by using the MT sounding curves and phase tensors. Three-dimensional (3D) MT inversion was performed to determine the electrical resistivity structure beneath the Cuonadong dome. The preferred 3D electrical resistivity model shows that an obvious low-resistivity anomaly develops beneath the Cuonadong dome which is overlaid by a high-resistivity body and surrounded by an apparent subcircular zone of low-resistivity anomalies. The integrated conductivity (longitudinal conductance) from depths of 1–20 km indicates that the average longitudinal conductance at the core of the Cuonadong dome is about 10,000 S. The high-conductivity anomaly at the core is found to be analogous to that of lava, mainly resulting from the crustal partial melting, and the estimated melt content is 11.0–17.3%. The high conductance surrounding the dome reaches 20,000 S on average, which is mainly attributed to saline fluids. MT results in this study support that the Cuonadong dome experienced magmatic diapirism. Taken together with previous geological and geochemical studies, we suggest that under the east-west (E-W) extensional tectonic setting in southern Tibet, deep crustal partial melting constantly accumulated beneath the dome, and therefore the magmatic diapirism resulted in the formation of the Cuonadong dome. In addition, the MT results also indicate that the development of the Cuonadong dome provides abundant mineralizing fluids and the space for migration of metallogenic fluids for (rare-metal) polymetallic mineralization. [ABSTRACT FROM AUTHOR]

The North Himalayan gneiss domes (NHGD), as one of the extensional structures widely distributed across the southern Tibetan Plateau, are an important window for studying post-collisional diastrophism and magmation as well as polymetallic mineralization. However, the deep mechanism for the formation of NHGD remains controversial. The magneto-telluric (MT) method was adopted to study the deep structure of the Cuonadong dome in the Northern Himalayas. The characteristics of the dome were explored by using the MT sounding curves and phase tensors. Three-dimensional (3D) MT inversion was performed to determine the electrical resistivity structure beneath the Cuonadong dome. The preferred 3D electrical resistivity model shows that an obvious low-resistivity anomaly develops beneath the Cuonadong dome which is overlaid by a high-resistivity body and surrounded by an apparent subcircular zone of low-resistivity anomalies. The integrated conductivity (longitudinal conductance) from depths of 1–20 km indicates that the average longitudinal conductance at the core of the Cuonadong dome is about 10,000 S. The high-conductivity anomaly at the core is found to be analogous to that of lava, mainly resulting from the crustal partial melting, and the estimated melt content is 11.0–17.3%. The high conductance surrounding the dome reaches 20,000 S on average, which is mainly attributed to saline fluids. MT results in this study support that the Cuonadong dome experienced magmatic diapirism. Taken together with previous geological and geochemical studies, we suggest that under the east-west (E-W) extensional tectonic setting in southern Tibet, deep crustal partial melting constantly accumulated beneath the dome, and therefore the magmatic diapirism resulted in the formation of the Cuonadong dome. In addition, the MT results also indicate that the development of the Cuonadong dome provides abundant mineralizing fluids and the space for migration of metallogenic fluids for (rare-metal) polymetallic mineralization. [ABSTRACT FROM AUTHOR]

Background: Tumor-associated macrophages (TAMs) constitute the main infiltrating immune cells in the solid tumor microenvironment. Amounting studies have analyzed the antitumor effect on immune response induced by Toll-like receptor (TLR) agonists, such as lipopolysaccharide (LPS), γ-interferon (γ-IFN), and palmitic Acid (PA). However, their combined treatment for gastric cancer (GC) has not been illuminated. Methods: We investigated the relevance of macrophage polarization and the effect of PA and γ-IFN in GC in vitro and in vivo. M1 and M2 macrophage-associated markers were measured by real-time quantitative PCR and flow cytometry, and the activation level of the TLR4 signaling pathways was evaluated by western blot analysis. The effect of PA and γ-IFN on the proliferation, migration, and invasion of GC cells (GCCs) was evaluated by Cell-Counting Kit-8, transwell assays, and wound-healing assays. In vivo animal models were used to verify the effect of PA and γ-IFN on tumor progression, and the M1 and M2 macrophage markers, CD8 + T lymphocytes, regulatory T cells (Treg) cells, and the myeloid-derived suppressor cells (MDSCs) in tumor tissues were analyzed by flow cytometry and immunohistochemical (IHC). Results: The results showed that this combination strategy enhanced M1-like macrophages and diminished M2-like macrophages through the TLR4 signaling pathway in vitro. In addition, the combination strategy impairs the proliferative and migratory activity of GCC in vitro and in vivo. While, the antitumor effect was abolished using the TAK-424 (a specific TLR-4 signaling pathway inhibitor) in vitro. Conclusions: The combined treatment of PA and γ-IFN inhibited GC progression by modulating macrophages polarization via the TLR4 pathway. [ABSTRACT FROM AUTHOR]

Because of its high sensitivity to misalignment, precision grinding of free-form surfaces with micron accuracy requires accurate registration of the surface measurement point cloud. Registration of point clouds obtained with a coordinate measuring machine (CMM) is generally an iterative process of finding optimal coordinate transformation between the CMM frame and the model frame of the workpiece by minimizing the point-to-surface distances with probe radius compensation. For free-form surfaces, frequent calculation of point-to-surface distances consumes very much time, and a trade-off has to be made between the efficiency and the accuracy. This paper presents a method for fast registration of free-form surface point clouds based on the point-to-triangle distance which involves only Delaunay triangulation of a two-dimensional dataset, and the surface normal is quickly calculated from cross product. Probe radius compensation is realized by registering the probe center points with the offset surface. We prove that it is equivalent to registering the probe contact points with the nominal surface through theoretical analysis. The registration problem is then formulated as sequential linear least-square problems with properly defined ball constraints. To validate the method, numerical simulations are presented to show the accuracy of the point-to-triangle distance. The registration algorithm also shows excellent robustness against misalignment of tens of millimeters/degrees. Finally measurement, registration, and grinding of a free-form optical surface are experimentally demonstrated. The surface error obtained after registration is used for compensatory grinding which reduces it to micron level. [ABSTRACT FROM AUTHOR]

As interference waves in deep reflection data processing, surface waves are often suppressed as noise, but surface waves carry considerable underground media information, including structural information and the physical properties of rocks. Reasonable extraction and use of surface wave signals are of great significance when studying shallow characteristics. Deep reflection data are collected using large offsets, trail spacing, and explosive sources. The surface wave energy tends to be stronger, and the high-frequency surface wave signal is abundant. After extraction and inversion, the shallow shear wave velocity structure can be obtained. Near the Cuonadong dome in the southern Tibetan detachment system (STDS), a large number of leucogranites are developed in the core, containing important rare metal minerals and high metallogenic potential. However, studies regarding the shallow structure in this region are rare. In this paper, we use deep reflection data from a profile through the Cuonadong dome to obtain the S-wave velocity structure of the study area by extracting the surface wave fundamental-mode dispersion curve and inversion. Combined with regional geological and magnetotelluric data, we supposed that the thickness of the Cuonadong dome sediment layer (< 1.4 km/s) varies greatly from east to west, the thickness of the sediment layer is the deepest near the Cuona fault and Jisong fault (more than 1 km), and the core of the dome is the thinnest. Under the Cuonadong dome, there are obvious high-velocity anomalies (> 2.2 km/s), and the horizontal S-wave velocity changes greatly, which is mainly related to the destruction of magmatic activity since the Miocene. These understandings of the structure and velocity field of the Cuonadong dome can provide a powerful geophysical basis for establishing the dome structure model and searching for hidden ore bodies. [ABSTRACT FROM AUTHOR]

Alternative energy sources, derived from biomass feedstocks, are important for China's energy security. To evaluate China's capacity for bioenergy in the future, Geographic Information System (GIS) techniques were adopted to identify potentially productive marginal areas for the growth of 16 energy crops and to comprehensively estimate their biomass and bioenergy production potential under three scenarios. The results showed that a total of 267.23 Mha (i.e., million hectare) of marginal land was available for energy crop production. When assessing the suitability of individual environments for each type of energy crop, the largest total land area of a lignocellulosic energy crop, an oil energy crop, and a lignocellulosic energy tree were 3.64 Mha (Miscanthus spp.), 45.44 Mha (Jatropha curcas L.), and 63.55 Mha [Haloxylon ammodendron (C. A. Mey.) Bunge], respectively. In addition, the proposed production of bioethanol [Sorghum bicolor (L.) Moench], biodiesel [Swida wilsoniana (Wanger.) Sojak], and bio-electricity [H. ammodendron] in the baseline scenario met 31.83%, 26.08%, and 9.2% of ethanol demand for E10, diesel, and electricity in 2016, respectively. Furthermore, if upland and forest land could be used to produce bioenergy, the bioethanol substitution rates of ethanol for E100, diesel, and electric power were calculated as 62.63%, 153.94%, and 60.47%, respectively, for 2040. The results indicated that China's future energy demands could not be satisfied by simply depending on energy crops in most situations. Future bioenergy should be developed based on reliable supplies of several types of biomass materials and dedicated biochemical or thermochemical conversion processes, among other renewable energy sources. [ABSTRACT FROM AUTHOR]

Coronavirus disease 2019 (COVID-19), defined by the World Health Organization (WHO), has affected more than 50 million patients worldwide and caused a global public health emergency. Therefore, there is a recognized need to identify risk factors for COVID-19 severity and mortality. A systematic search of electronic databases (PubMed, Embase and Cochrane Library) for studies published before September 29, 2020, was performed. Studies that investigated risk factors for progression and mortality in COVID-19 patients were included. A total 344,431 participants from 34 studies were included in this meta-analysis. Regarding comorbidities, cerebrovascular disease (CVD), chronic kidney disease (CKD), coronary heart disease (CHD), and malignancy were associated with an increased risk of progression and mortality in COVID-19 patients. Regarding clinical manifestations, sputum production was associated with a dramatically increased risk of progression and mortality. Hemoptysis was a risk factor for death in COVID-19 patients. In laboratory examinations, increased neutrophil count, decreased lymphocyte count, decreased platelet count, increased C-reactive protein (CRP), coinfection with bacteria or fungi, increased alanine aminotransferase (ALT) and creatine kinase (CK), increased N-terminal pronatriuretic peptide (NT-proBNP), and bilateral pneumonia in CT/X-ray were significantly more frequent in the severe group compared with the non-severe group. Moreover, the proportion of patients with increased CRP and total bilirubin (TBIL) was also significantly higher in the deceased group than in the survival group. CVD, CKD, sputum production, increased neutrophil count, decreased lymphocyte count, decreased platelet count, increased CRP, coinfection with bacteria or fungi, increased ALT and CK, increased NT-proBNP, and bilateral pneumonia in CT/X-ray were associated with an increased risk of progression in COVID-19 patients. Moreover, the proportion of patients with increased sputum production, hemoptysis, CRP and TBIL was also significantly higher in the deceased group. [ABSTRACT FROM AUTHOR]