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Several anti-Aβ monoclonal antibody drugs have been approved for clinical use at home and abroad recently. In order to facilitate its safe and effective treatment of anti-Aβ monoclonal antibody drugs for Alzheimer's disease (AD) in China, we present recommendations for the clinical use of anti-Aβ monoclonal antibody drugs based on existing clinical trials and the clinical practice of AD treatment with Aducanumab at Ruijin Hospital Hainan Branch, Shanghai Jiaotong University School of Medicine. The recommendations include clinical indications, pre-medication assessment and preparation, medication instructions and precautions, as well as post-medication clinical monitoring, which is aimed to furnish clinicians with comprehensive medication guidance. [ABSTRACT FROM AUTHOR]

In order to accurately measure the 3D temperature distribution of solid rocket motor plume, a radiation temperature measurement model of solid rocket engine plume was established. Aiming at the problems of low accuracy and poor robustness of reconstruction algorithm in current radiometric temperature measurement technoiogy, a reconstruction method of solid plume three-dimensional temperature field based on LM-GAUSS hybrid algorithm was proposed. The effects of radiation intensity noise, absorption coefficient noise, different noise levels and meshing method were studied by numerical simulation. Compared with the simulation results of traditional LSQR and NNLS reconstruction algorithms, the simulation results show that the reconstruction accuracy of the algorithm is better than 5%o when the noise is less than 10%, which proves the performance of the proposed hybrid algorithm with high reconstruction accuracy and strong robustness. The 3D temperature field reconstruction experiment of ethylene flame was carried out in the laboratory, which proved the applicability of LM-GAUSS and provided the support for the foliow-up field measurement of solid engine plume temperature. [ABSTRACT FROM AUTHOR]

Background DSA is an irreplaceable diagnostic method for cerebral vascular disease. It is sensitive to intracranial macrovascular disease, but not to distal blood perfusion. In order to quantitatively assess the perfusion area of the feeding artery, this study is the first to propose an imaging method of the internal carotid artery (ICA) perfusion area relying on deconvolution algorithm and cross - correlation (CC) algorithm. Methods Four patients with cerebral vascular disease and 2 healthy subjects who underwent DSA examination in Luwan Branch of Ruijin Hospital Affiliated to Shanghai Jiaotong University School of Medicine from June 2020 to May 2021 were enrolled. The arterial input function (AIF) of the ICA was extracted, and a deconvolution algorithm was used to calculate the time to peak (Tmax) for each pixel. Then the CC algorithm was used to obtain the CC map related to the perfusion of the ICA at each pixel point of the whole brain. Area of interest (ROI) of AIF were randomly selected for 2 healthy subjects, calculated the root mean square error (RMSE) of the CC map for reliability analysis. The CC map was drawn for 4 patients with cerebral vascular disease for validity analysis. Results Reliability analysis showed that the RMSE values of Towne's and lateral views of the CC map and Tmax map of the left and right ICA in a healthy subject were 0.008 ±0.011, 0.022 ± 0.002, 0.015 ±0.007, 0.004 ±0.008, and (0.108 ± 0.181) s, (0.181 ± 0.214) s, (0.301 ± 0.230) s, (0.035 ± 0.092) s; another healthy subject were 0.015 ± 0.023, 0.007 ±0.011, 0.007 ±0.011, 0.005 ±0.012, and (0.172±0.275) s, (0.092 ± 0.174) s, (0.087±0.156) s, (0.079± 0.153) s. The averaged RMSE value of Tmax map was lower than the temporal resolution of DSA, indicating that the reliability of the CC map of the AIF value box in different ROIs of the ICA was high. Validity analysis showed that the CC map and Tmax map of the patient with acute ischemic stroke treated by intravenous thrombolysis bridging to mechanical thrombectomy can fully display the perfusion changes of the ICA after successful thrombectomy. Postoperative DSA in the patient with subacute ischemic stroke after endovascular therapy showed recanalization of the occluded artery, while the CC map showed no significant change in the perfusion of the ICA. The DSA of the patient with middle cerebral artery (MCA) stenosis without related ischemic events showed severe MCA stenosis, but the CC map showed that the ICA was well perfused, and no endovascular treatment was required. The DSA of the patient with acute ischemic stroke without MCA stenosis showed no MCA stenosis, but only sparse ICA-related perfusion was seen on the CC map. Conclusions The CC map and Tmax map based on DSA images have good reliability in different ROIs of AIF. The CC map can provide quantitative information on the perfusion area of the feeding arteries, which is helpful for accurate diagnosis and appropriate treatment decisions. [ABSTRACT FROM AUTHOR]

Ammonia is an important industrial raw material and a potential green energy. Using renewable energy to convert nitrogen into ammonia under ambient condition is an attractive method. However, the development of efficient photoelectrochemical ammonia synthesis catalysts remains a challenge. Perovskite such as BaSrTiO3 (BST) is a good photocatalytic material. However, BST is active under ultraviolet light and has a high recombination rate of photogenerated electron-hole pairs. By dispersing precious metals, it can effectively regulate the absorption of sunlight by BST. In this work, we used a two-step method to prepare BST. The H2PtCl6⋅6H2O solution was dispersed on the BST, and then followed by calcination in a tube furnace to obtain Pt@BaSrTiO3 (Pt@BST). X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were utilized to analyze the structures, morphologies, and surface chemical composition of the synthesized materials. Results showed that the well-crystallized Pt particles were successfully loaded onto the BST surface, and Pt and BST interacted to produce a metal-semiconductor heterojunction, improving the performance of N2 reduction. The N2 adsorption and desorption isotherms showed that the increase in the specific surface area helped the catalyst to adsorb N2, and the contact area with H2O also increased, which promotes the occurrence of NRR and thus produces more NH3. UV-Vis and PL spectroscopic techniques were used to characterize and analyze optical properties of the obtained catalyst. It is indicated that decoration of Pt reduces the band gap of the catalyst and increases the visible light absorption range, in addition, further enhances the charge separation and transfer, inhibits the recombination of electron-hole pairs, and improves the efficiency of charge separation. The performances of BST and Pt@BST for photoelectric catalytic synthesis of ammonia under ambient condition were studied. The yield of ammonia first increased and then decreased with the increase of Pt content. When the Pt content was 4wt%, the yield was the highest. The results showed that the ammonia yield of Pt@BST was 26.57 x 10-8 mol⋅h-1⋅mg-1 and Faraday efficiency (FE) was 5.43% at -0.3 V (vs. RHE) in 0.1 mol⋅-1 Na2SO4 under natural conditions, suggesting that the ammonia yield of Pt@BST was twice that of pure BST (13.12 x 10-8 mol⋅h-1⋅mg-1). We conducted control experiments of 15N2 isotope and Ar in order to eliminate internal and external environmental pollution. Confirming that the detected NH3 was produced exclusively via nitrogen reduction reaction. After recycling the test six times at -0.3 V (vs. RHE), both FE and ammonia yield rate showed a slight variation, indicating the high stability of Pt@BST during N2 reduction process. This work provides a simple strategy for further designing the preparation of noble metal modified perovskite catalysts, and has promising application prospects in ammonia synthesis under ambient condition. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is one of most common neurodegenerative diseases, which gradually begins and develops after 65 years old, presenting as progressive and irreversible memory loss and other cognitive decline, and finally causes dementia and disability. Therefore, early diagnosis, timely treatment and effective prevention of AD have been become important clinical and scientific problems. During the period of Twelfth Five-Year Plan for National Economic and Social Development, our team have engaged in AD diagnosis and treatment for a long time and carried out studies in the field of pathogenesis, epidemiology, screening of risk factors, neuropsychological tests, imaging, biomarkers and early intervention of AD. This paper has summarized these research achievements. [ABSTRACT FROM AUTHOR]

The article offers information on a study which investigates culture, identification and biological characteristics of newborn calf osteoblasts. It notes that the coastal bone from a new-born calf was digested five times with trypsin, and was manually fragmented into bone flaps. It mentions that the properties of osteoblasts are possessed by isolated and cultured cells.

Given that the conventional blockchain model for the fruit and vegetable supply chain has the problems of insufficient depth of traceability information, insufficient data correlation, and low query efficiency, a graph blockchain model was proposed in this study. Firstly, the graph theory was used to improve the block data structure of the traditional blockchain and change the storage structure of the sequence table in the traditional blockchain structure into a graph structure that can facilitate the storage of in-depth traceability information for associated storage of deep traceability information. Then, the mapping relationship between physical block data and graph block chain model was established through a graph block chain mapping model, and according to the logical structure of the fruit and vegetable supply chain, the graph block data structure was established. Customized design of smart contracts for graph blockchain data storage, query and authority management was performed to ensure the reliability of supply chain data. Finally, the graph blockchain model was developed based on the XuperChain platform and its performance was experimentally compared with that of the traditional blockchain. The results showed that the graph blockchain allows deep traceability of the fruit and vegetable supply chain and greatly improves the efficiency of data query, which can provide a new method and idea for the traceability information storage and fast query of the fruit and vegetable supply chain based on blockchain.

During the initial casting stage of the IF steel, the cleanliness of the first slab deteriorates. Steel plants treat the initial casting slabs as waste or demoting products. Moreover, the cleanliness deterioration of initial casting slabs leads to unstable quality and low product yield. In the present study, to investigate the cleanliness of continuous casting slabs and the optimization measures during the initial casting stage of the IF steel, the cleanliness of the initial casting slabs is evaluated by field sampling and experimental analysis. Moreover, the effect of the casting speed rising method on the cleanliness of the IF steel slab during the initial casting stage is investigated. Additionally, numerical simulations are conducted to reveal the level of fluctuations of the molten steel in the mold during the initial casting stage. The results show that the variations in T[O], [N], and the content of microinclusions in the slab decrease obviously along the casting direction. The contents of T[O] and [N] in the slab reach the normal slab level of 6 m (approximately 13×10−6) and 7 m (approximately 19×10−6) away from the dummy bar head, respectively. Nevertheless, the effects of the casting speed rising method on the contents of T[O], [N], and microinclusions in the initial casting slabs are inapparent during the open casting process. For the three conditions of open casting (different casting speed rising methods), the contents of the macroinclusions in the slab reach the normal slab level of around 2 m (approximately 2 mg/10 kg) away from the dummy bar head, respectively. Subsequently, the fluctuation of the macroinclusion content can be determined. Furthermore, under the condition of “quick-slow” casting speed rising, the fluctuation can be quickly alleviated, and the macroinclusion content normalizes. Numerical simulations reveal that the variations in the fluctuation level of the molten steel at different positions (near the nozzle, a quarter of the width, and near the narrow face) in the mold during the initial casting stage of the three casting speed rising modes are similar. First, the fluctuation level is extremely intense. Then, the fluctuation level gradually weakens for some time. Finally, the fluctuation level of the molten steel at different positions in the mold stabilizes. Additionally, the numerical simulation results reveal that the slab cleanliness can quickly normalize (430 s after initial casting and about 5 m away from the dummy bar head) under the “quick-slow” casting speed rising mode during the initial casting stage.

The surface and corner cracks of continuous casting billet form during the continuous casting process, especially in medium-carbon steel. Surface defects of such billets are directly related to the secondary cooling process of continuous casting, while the center deviation of the billet, center shrinkage, and center loosening in medium-carbon steel, medium-carbon alloy steel, and high-carbon steel are especially prominent. Such quality defects are related to the secondary cooling and press-down process of continuous casting. These two defects are the main factors restricting continuous casting production. The secondary cooling of the continuous casting process has an important influence on the surface and internal quality of the slab, especially the temperature of the slab corners, which directly affects the surface quality of the slab. Under the existing process conditions, the mathematical model for calculating the solidification heat transfer of the slab in the secondary cooling zone is calibrated and improved, and a three-dimensional secondary cooling model is developed to solve the influence of uneven cooling due to water distribution on the temperature of the slab. This controls the surface quality of the slab, especially the corner cracks of the slab, and improves and optimizes the slab continuous casting secondary cooling system to improve the slab quality. An equation for calculating the soft reduction parameters is proposed, and the existing soft reduction process is optimized by combining the developed three-dimensional secondary cooling model with the proposed and applied controllable single-stage soft reduction and unsteady soft reduction control to solve the internal quality problems, such as central segregation, central porosity, and shrinkage of the continuous casting slab. At the same time, the model database is optimized to make the data more complete and the model calculation more accurate. This model adds the technology of mixed casting of different grades of steel and the technology of predicting and controlling the W-shaped solidification to further improve the applicability and accuracy of the model. The model has been developed and successfully applied in several steel plants, and the result shows that the proposed model can improve the surface and internal quality of cast slabs effectively, such as cracks and segregation.

Continuous casting technology has greatly improved production efficiency; however, in the continuous casting process of heavy rail steel, problems of center segregation, center porosity, and shrinkage cavity of the bloom occur, which notably affect the billet quality of heavy rail steel. The soft reduction technique can effectively improve these problems, but internal cracks will appear, and the quality of the bloom will deteriorate if the parameters are not properly set. To examine the inner crack induced by the soft reduction of continuous casting bloom, this study established a mathematical model for the soft reduction of a 230 mm×280 mm section bloom by the ABAQUS finite-element software. The thermal-stress coupling model was used to predict the inner crack of the heavy rail steel bloom, using the soft reduction model during the soft reduction process. First, the temperature at different central solidification fractions of 0.3–0.7 in the bloom was calculated. The equivalent plastic strain that was located at the solidification front at different central solidification fractions was then calculated by the soft reduction model. Results indicated that the equivalent plastic strain at the solidification front in the bloom did not exceed the critical strain of 0.4% at the central solidification fractions with a reduction amount of 7 mm. Moreover, the inner crack did not occur at the solidification front. Simultaneously, the soft reduction model calculation with a different reduction amount was conducted at the central solidification fraction of 0.6. Results showed that the equivalent plastic strain at the solidification front exceeded the critical plastic strain of 0.4% when the reduction amount was more than 7 mm, which resulted in an inner crack. The greater the reduction amount, the more serious is the inner crack. Concurrently, industrial experimental results had a good agreement with the model calculation results.

Alzheimer's disease (AD) is one of most common neurodegenerative diseases, which gradually begins and develops after 65 years old, presenting as progressive and irreversible memory loss and other cognitive decline, and finally causes dementia and disability. Therefore, early diagnosis, timely treatment and effective prevention of AD have been become important clinical and scientific problems. During the period of Twelfth Five-Year Plan for National Economic and Social Development, our team have engaged in AD diagnosis and treatment for a long time and carried out studies in the field of pathogenesis, epidemiology, screening of risk factors, neuropsychological tests, imaging, biomarkers and early intervention of AD. This paper has summarized these research achievements. DOI: 10.3969/j.issn.1672-6731.2018.02.004

Pannexin1 (Panx1) is a subtype of the newly discovered gap junction proteins named Pannexin(s). Panx1 is widely expressed in the nervous system, cardiovascular system, etc and can form non-selective and large conductance hemichannel. It has been demonstrated that various conditions can regulate Panx1 open and affect the body's physiological function via macromolecular substance (for instance, ATP) releasing. This review gives a detailed introduction to the main distribution of Panxl, summarizes the open and inhibition condition of Panx1, and finally, prospects directions of future research.