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Objective To explore the expression of triggering receptor expressed on myeloid cells 2 (TREM2) in high-glucose microglia and to investigate the role of TREM2 in the proliferation, migration and phagocytosis of high-glucose microglia. Methods Microglia cells were divided into control group and high-glucose treatment group(67.5 mmol/L glucose, 24 h). The microglia cells were counted and the expression of Iba1 and TREM2 was detected. TREM2 siRNA was transfected to detect the proliferation and migration of microglia. The amyloid β-peptide (Aβ) with a fluorescent tag was added to observe the phagocytosis of Aβ by microglia. Results Compared to normal microglia, the number of microglia significantly decreased after high-glucose treatment (P＜0.001), while the expression of TREM2 and Iba1 markedly increased (P＜0.001). High glucose and TREM2 did not affect the proliferation of microglia. Compared to the normal group, the migration of microglia significantly decreased after high-glucose treatment (P＜0.05) and TREM2 did not affect the migration ability of high-glucose microglia. Compared to the normal group, the phagocytosis of Aβ by microglia significantly decreased in the high-glucose treated group(P＜0.001). Furthermore, TREM2 knockdown further decreased the phagocytosis of Aβ by high-glucose microglia (P＜0.001). Conclusions The expression of TREM2 in microglia significantly increases after high-glucose treatment, which significantly affects phagocytosis of Aβ by microglia.

Hot deformation behavior of as-cast BFe30-1-1 alloy was systematically investigated at the temperature of 750-1000 ℃ and the strain rate of 0.01-10 s-1. The effects of friction and adiabatic on the flow stress were analyzed. The stain-stress curves caused by frictional and adiabatic effects were corrected. The corrected curves were used to establish the Arrhenius constitutive equation, so as to the processing map of as-cast BFe30-1-1 alloy on the basis of dynamic material model. The microstructure evolution of alloy during hot deformation was investigated, which shows that the flow-stress increases with the decrease of deformation temperature and the increase of strain rate. Friction and temperature rise can influence the flow stress curves of alloys. The dynamic recrystallization occurs during the hot deformation. The average relative error between the predicted value and the experimental value of peak stress is less than 3.77%. It shows that the constitutive equation can accurately predict the flow stress of different hot deformation conditions. According to the hot processing map and microstructural analysis, the reasonable range of thermoplastic deformation process for BFe30-1-1 copper-nickel alloy is the deformation temperature of 900-1000 ℃ and the strain rate of 0.04 - 0.16 s-1. And more dynamic recrystallization grains of the alloy can be obtained at this deformation condition.

Public goods for the global ocean sustainable development (GOSD) are key to promoting the sustainable development of oceans globally. To understand the utilization and protection status of global ocean resources as well as the international cooperation and trend regarding GOSD, this study summarizes the current status and development trends of the GOSD public goods in China and abroad, analyzes the major scientific and technological problems and challenges faced by China in related fields, and proposes the development priorities of the GOSD public goods in terms of engineering technologies. Furthermore, it proposes that China should boost its comprehensive strength in ocean science and technology by establishing an effective mechanism for ocean observation and data sharing and enhance international cooperation and strategic planning to promote its international influence in the field of GOSD public goods.

[Objective] The effects of different mulching methods on the distribution of organic and inorganic carbon in soil aggregates on the Loess Plateau, and the mechanism under which soil aggregates sequester carbon under mulched conditions were determined in order to promote efficient management of dryland farm soil. [Methods] The study was conducted on a long-term positioning experiment beginning in 2012. Soil characteristics were studied from plots on which spring corn (“Xianyu 335”) was grown under three treatments: straw mulching (SM), film mulching (FM), and no mulching (CK). Carbon distribution and enzyme activities in aggregates of different particle sizes were determined by the wet sieve method. [Results] ① Organic carbon contents of aggregates of each particle size were significantly greater for SM than for CK (p2 mm in size, but significantly increased the reserves of aggregates 2 mm to 0.25 mm in size (p

Longwall mining with large cutting height serves as one of main methods for extracting thick coal seam. Face failure gradually becomes a critical phenomenon due to significant increase of the cutting height, which drastically influences the mining efficiency in such longwall faces. In order to improve surrounding rock stability and mining efficiency of such faces, the influence of support stiffness on face stability is thoroughly investigated by using theoretical analysis, laboratory testing and field measurements. The results show that three kinds of face failure patterns commonly appear in longwall face with large cutting height, including splitting pattern of hard coal seam, shearing pattern of relatively hard coal seam and plastic flow pattern in soft coal seam. A safety factor is proposed for longwall face, which is defined as the ratio of the difference between load-bearing capacity of the face and roof load applied on the face to the referred roof load. The influence of roof load on distribution of the safety factor is obtained. A model is developed for roof impact phenomenon, determination method of the load exerting on the face by roof is deduced. The relation between support stiffness and face stability coefficient is achieved. With the increase in support stiffness, the load applied on the face decreases and the face stability is strengthened. However, the sensitivity of the load and face stability to support stiffness decreases gradually. Physical modeling of the influence provided by support stiffness on face stability is carried out. With the support stiffness of 1.0, 1.5 and 2.0 MN/m, load-bearing capacity of the face increases from 17 to 19 and then to 20 kN. The largest horizontal displacement decreases from 40 to 30 and then to 25 mm. After failure, the broken areas are about 0.41, 0.32 and 0.21 m2, respectively, in the referred scenarios. At last, the face stability of 31402 longwall face in Wulanmulun coal mine is effectively improved by increasing the support stiffness.

The effect of carbon nanotubes (CNTs) on the aging behavior of Mg-9Al matrix composites was studied, and the evolution of microstructures, mechanical properties and thermal conductivity of composites during the aging treatment were discussed. Results show that the addition of CNTs increases the solid solubility of Al in Mg matrix and limited the migration of grain boundaries during the aging process, which can promote the formation of continuous precipitated phases β-Mg17Al12 in CNTs/Mg-9Al composites. The rod-shaped continuous precipitates in coherent relationship with Mg matrix can effectively hinder the dislocation movement, which can improve the mechanical properties of the composites. Besides, the reduction of solid solution Al atoms during aging process and the addition of CNTs can improve the thermal conductivity of the composites. The property evaluation indicates that the tensile yield strength, ultimate tensile strength, diffusivity and thermal conductivity of peak-aged 0.4CNTs/Mg-9Al composite are 275 MPa, 369 MPa, 34.5 mm2/s and 68.4 W/(m·K) respectively, showing 17%, 23%, 43% and 45% increasing in comparison with those of Mg-9Al before aging.

Since widely accepted by international scholars, Voussoir Beam Theory proposed by Academician Minggao Qian helps the research on underground mining pressure realize leapfrog development from the stage of qualitative hypothesis to quantitative analysis. In the past forty years, an integral system has been formed for strata movement theory and strata control technique, contributing to safe, efficient and green mining of underground coal seams. By underlining the voussoir beam theory, critical developments on strata movement and its control have been reviewed. Important topics are proposed for future research. In the voussoir beam theory, rupture characteristics of main roof are studied with beam and thin plate models. It is revealed fracturing line of main roof locates ahead of the longwall face. Due to supporting effects provided by coal wall and caving materials, the rotation of broken blocks of main roof results in the occurrence of compressive force, forming the voussoir beam structure. Both slipping and rotating instability modes of the structure are identified. The S-R instability conditions are determined. Based on such understanding, determination method for roof load is proposed through keeping the balance of voussoir beam structure, realizing quantitative analysis on the relation between hydraulic support and surrounding rock. Until now, the voussoir beam structure stands as the most impeccable model for explaining underground mining pressure. It is a major breakthrough for conventional qualitative hypothesis, which makes historic contributions to living safety and working efficiency of the miners. The Voussoir Beam Theory further brings about many achievements on strata control, including three-coupling relation between hydraulic support and surrounding rock, dynamic load model for roof control, medium plate model, far-near field model in longwall face with large space etc. Based on the voussoir beam theory, the key stratum theory is moreover proposed by Minggao Qian in the middle of the 1990s. Mechanical relation between different overburden strata is established during movement process. Coordinative analysis on mining pressure, strata movement and surface subsidence is realized. The Voussoir Beam Theory and key stratum theory provide significant guidance on the research of coal mining pressure and strata movement, contributing to a series of theoretical developments, such as mining pressure control at the face area, mining induced fracture distribution in strata, mining induced stress distribution, strata movement and surface subsidence. Such achievements serve as the foundation of green mining and scientific mining. Further development of the theory should pay attention to unified field theory for strata movement, strata movement based accident and damage prevention technique, strata movement under complex mining conditions, visualization of strata movement and intelligent strata control.

The Mg-xGd-1Er-1Zn-0.6Zr alloys with Gd contents of 7%(mass fraction), 9% and 11% were prepared by gravity casting method.The microstructure of the alloys was studied by means of optical microscope, scanning electron microscope and X-ray diffractometer.The corrosion behavior of the alloys were evaluated by means of open circuit potential, potentiodynamic polarization and electrochemical impedance spectroscopy measurements in 3.5%NaCl solution.The results show that when Gd content increases from 7% to 11%, the peak time of open circuit potential decreases from 1609 s to 851 s, the charge transfer resistance decreases from 588.50 Ω to 31.9 Ω, the corrosion current density increases from 2.21×10-5 A/cm2 to 3.97×10-5 A/cm2, indicating that the corrosion resistance of the alloys decreases with the increase of Gd content.It is attributed to the combined operation of the micro-galvanic corrosion effect as well as corrosion barrier effect of second phase.When the Gd content increases from 7% to 11%, the volume fraction of (Mg, Zn)3(Gd, Er) phase increases from 1.9% to 5.2%, and changes from discontinuous distribution to semi-continuous distribution along grain boundaries, the volume fraction of the lamellar-shape LPSO phase increases from 11.7% to 26.7% and penetrates into grains.The increase in the volume fraction of the (Mg, Zn)3(Gd, Er) phase and the lamellar-shape LPSO phase results in the decrease of corrosion resistance, however, a large number of fine lamellar-shape LPSO phases is able to prevent the corrosion from spreading and slow down the growth of corrosion rate of the alloy with 11%Gd content in 8-24 h.

Objective To explore the imaging characteristics of the mandibular nerve canal in adults to provide a reference for clinical mandibular surgery.Methods One thousand adult patients in Guiyang Stomatological Hospital from January 2018 to January 2021 were randomly selected. Cone beam CT (CBCT) was used to observe the anterior mandibular canal and other branches, and the incidence of anterior canal in the mandibular ramus area, posterior molar area and molar area and the distance to each point of the mandible were measured.Results Of the 901 patients (1 802 sides) included in the study, 386 patients (42.84%) found branches of the mandibular canal, and 182 patients (97 males and 85 females) found the Anterograde Canal 20.20% (182/901). In total, 225 mandibles were found to have anterior canals. There were 101 cases of left mandible and 124 cases of right mandible. The forward canal mainly occurred in the molar area, the molar posterior area and the ascending branch area, and the ascending branch area was the best starting point of the forward canal and the molar stopping point (P < 0.05). The average length of the forward canal (L1) was (10.364 ± 3.833) mm, the average height of the forward canal to the main trunk of the mandibular nerve (L2-RRB) was (3.623 ± 2.035) mm, and the average height of the forward canal to the crest of the alveolar ridL3 (l3) was (9.280 ± 3.240) mm.Conclusion Mandibular nerve canal branches are common, and there were no differences in male, female and lateral distribution. In this study, the incidence of mandibular anterior canal was the highest, and it often occurred in the molar area.

Stiffened plates is a common structural form in aviation structure. Different types of stiffened plates and different manufacturing processes will affect its mechanical behavior and failure mode. The finite element method is used to establish numerical models of titanium alloy stiffened plates, and to study the effects of the T, L and Z type stiffened plates on buckling mode and failure. The influence of manufacturing processes such as welded, spot welded, riveted and integral panels on buckling and post buckling properties are analyzed. It is shown that the buckling load and the failure load of the T-type stiffened plate are the maximum one. Different manufacturing processes have great influence on the failure load and post-buckling load capacity, among which the post-buckling load capacity of welded stiffened plate is the largest one. At the same time, the most effective stiffening method of 600 mm×600 mm stiffened plate structure is given.

Objective: To investigate the clinicopathological characteristics of gastric schwannomas (GSs). Methods: The 31 GS cases, including 12 males and 19 females with a median age of 51 years (22-70), of 17 223 surgical procedures performed from January 2014 through March 2020 were retrieved for histological and immunological studies. The diagnosis, differentiation, treatment and prognosis were discussed with reference to relevant literatures. Results: The pre-operative imaging study suggested gastrointestinal stromal tumor(GIST) in 20 cases. Only two patients had the tumor breaking the serosa, and the tumor found on 29 patients was located between the muscularis propria and serosa of the stomach. Histological examination revealed well-circumscribed tumor with a prominent peripheral lymphoid cuff. The tumor was mainly composed with spindle cells, arranged in bundles and small clusters or in a haphazard fashion. The common features of soft tissue schwannoma, such as Antoni A zone and Antoni B zone, were absent or rarely found. Although the atypical nucleus could be identified, the mitosis was rare or absent. GS were diffusely positive for S100 and SOX10. Conclusions: GS is a rare benign mesenchymal tumor of the stomach, most of which are easy to be misdiagnosed as gastrointestinal stromal tumor. The diagnosis should be established based on histological features and immunophenotypes.

Highly sensitive characterization of surface plasmon resonance (SPR) modes lays the solid foundation for wide SPR-related applications. Herein, we discover that these SPR modes based on all-metal nanostructures without any probed molecule can be characterized with ultrahigh sensitivities at both excitation and emission wavelengths by utilizing plasmon-enhanced sum frequency generation (PESFG) spectroscopy. The theory of PESFG for sensitively characterizing SPR modes is first validated experimentally. Moreover, we have elaborately demonstrated that PESFG strongly depends on both the resonant wavelengths of SPR modes and spatial mode distributions when azimuthal angles of excitations are varied. Our study not only enhances the understanding of the mechanism that governs PESFG, but also offers a potentially new method for exploring new-style SPR modes (e.g. plasmon-induced magnetic resonance and bound states in the continuum) by PESFG.

Abstract Objective The purpose of this study is to evaluate the association between PET/CT CFR and biomarkers combined in confirming the diagnosis of coronary microvascular dysfunction. Results A total of 28 patients (21 males and 7 females) were included in this descriptive observational study (both qualitative and quantitative). The mean patient age was 55.50 ± 10.21 years (range 27–70 years) and the median was 56.5 years (range 49–63 years). All patients underwent Echo, CAG and PET/CT scan. Chest tightness was the most common symptom in our study. Most patients had normal blood pressure (n = 18, 64.3%) while only (n = 10, 37.5%) had hypertension, and (n = 1, 3.6%) had diabetes mellitus. The mean HDL in CMVD (n = 25) and non-CMVD (n = 3) were 1.30 ± 0.39 and 1.08 ± 0.95, respectively, indicating that the difference between the groups was statistically significant (p = 0.04). Similarly, the mean HBA1c- (glycated haemoglobin) in CMVD (n = 25) and non-CMVD (n = 3) were 5.6 ± 0.53 and 5.0 ± 0.26, respectively, with (p = 0.03). Our findings managed to show the association between biomarkers and PET/CT CFR in confirming the diagnosis of coronary microvascular dysfunction.

Abstract Objective To improve current knowledge of coronary flow reserve and non-obstructive coronary artery disease in terms of definition, features and clinical implications of measurement of coronary flow reserve (CFR), is an integrated measure of focal, diffuse, and small vessel coronary artery disease, can also be explained as a calculated ratio of hyperaemic to rest absolute myocardial blood flow. Non-obstructive coronary artery disease is defined as atherosclerotic plaque that does not obstruct blood flow or result in anginal symptoms. We also aimed at knowing the significance of PET in diagnosing coronary microvascular disease. Results In our study 92% were between 41 and 60 years. 83% were males and 17% females, more patients had hypertension about 50%, few had diabetes mellitus about 16%, while those with both hypertension and diabetes mellitus were 17%. About 83% had ST segment and T wave changes on ECG. All patients and controls had normal coronaries on coronary angiography TIMI 3 flow. On further investigation by Positron emission tomography/CT we found out 58% had abnormal CFR and 42% had normal coronary flow reserve. Our findings indicate PET/CT coronary flow reserve concept provides a platform for the diagnosis of non-obstructive coronary artery disease in patients with signs and symptoms of ischemia without angiographic obstructive CAD.

New finite element methods are proposed for elliptic interface problems in one and two dimensions. The main motivation is to get not only an accurate solution, but also an accurate first order derivative at the interface (from each side). The key in 1D is to use the idea of Wheeler (1974). For 2D interface problems, the point is to introduce a small tube near the interface and propose the gradient as part of unknowns, which is similar to a mixed finite element method, but only at the interface. Thus the computational cost is just slightly higher than in the standard finite element method. We present a rigorous one dimensional analysis, which shows a second order convergence order for both the solution and the gradient in 1D. For two dimensional problems, we present numerical results and observe second order convergence for the solution, and super-convergence for the gradient at the interface.

Based on the principle of dilute solution approximation, a phase field model for dendritic growth during the non-isothermal solidification process was proposed by coupling the phase field, concentration field and temperature field, and was adopted to investigate the dendritic growth of Al-Cu binary alloy during the non-isothermal solidification process. Also, the simulations of free dendritic growth in an undercooled melt of Al-4.5%Cu binary alloy with different perturbation intensity and anisotropy were carried out by the present phase field model. The results show that during the non-isothermal solidification process of Al-4.5%Cu binary alloy, the dendrite grow into undercooled melt with the solute rejection and latent heat release at the front of solid/liquid interface, and the solute enriches at the dendrite root and high temperature appears at the dendritic growth front. With the increase of perturbation intensity, the dendritic growth becomes more developed and more branches appear. Moreover, the anisotropy coefficient also has a great effect on the dendritic growth, and the growth speed of dendrite increases with the increase of anisotropy coefficient.

The China spallation neutron source (CSNS) was built and started running since 2018. It produces neutrons by impinging 1.6 GeV protons onto a tungsten target with 25 Hz repetition frequency. A beam line exploiting the back-streaming neutrons (Back-n) was built mainly for nuclear data measurement and started commissioning simultaneously with CSNS in 2018. There are two experimental endstations along the Back-n beam line: endstation 1 (#ES1) with a neutron flight path of about 55 m and endstation 2 (#ES2) with about 76 m. The neutron energy spectra of both #ES1 and #ES2 were measured since it is important for feasibility study and analysis. In this paper, the measurement of the neutron energy spectrum of Back-n #ES1 is reported. It is measured by a multi-layer fission chamber using the 235U samples as the neutron converters. The neutron energy spectrum from 0.1 eV to 30 MeV is obtained. The integral neutron flux (from 0.1 eV to 30 MeV) normalized to the proton beam power of 100 kW is 1.55×107 neutrons/cm2/s.

In the past two decades cooperating with Frank Laboratory of Neutron Physics (FLNP), Joint Institute for Nuclear Research (JINR) measurements of (n, α) reaction cross sections for 6Li, 10B, 25Mg, 39K, 40Ca, 54,56,57 Fe, 58Ni, 63Cu, 64,67 Zn, 95Mo, 143Nd and 147,149 Sm nuclei were performed in the MeV neutron energy region based on the 4.5 MV Van de Graaff accelerator at Peking University. In recent years, our measurements were extended in three aspects. Firstly, measurements were expanded from two-body reactions to three-body reactions such as 10B (n, t2 α). Secondly, the neutron energy region was extended from below 8 MeV to 8 - 11 MeV by using the HI-13 tandem accelerator of China Institute of Atomic Energy (CIAE), with which cross sections of 54,56 Fe(n, α)53,51Cr reactions were measured. Thirdly, based on the newly-built China Spallation Neutron Source (CSNS) Back-n WNS (White Neutron Source), differential and angle-integrated cross sections for 6Li(n, t) and 10B(n, α) reactions were measured in the neutron energy region from 1 eV to 3 MeV.