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Understanding the spatial interaction of ultrasounds based on three-dimensional dual-frequency ultrasonic field numerical simulation

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China Foundry 2024年第1期21卷 29-43页

作者： Zhao-yang Yin qi-chi le Yan-chao Jiang Da-zhi Zhao qi-yu Liao qi Zou Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

A transient 3D model was established to investigate the effect of spatial interaction of ultrasounds on the dual-frequency ultrasonic field in magnesium alloy melt.The effects of insertion depth and tip shape of the ultrasonic rods,input pressures and their ratio on the acoustic field distribution were discussed in detail.Additionally,the spacing,angle,and insertion depth of two ultrasonic rods significantly affect the interaction between distinct ultrasounds.As a result,various acoustic pressure distributions and cavitation regions are obtained.The spherical rods mitigate the longitudinal and transversal attenuation of acoustic pressure and expand the cavitation volume by 53.7%and 31.7%,respectively,compared to the plate and conical rods.Increasing the input pressure will enlarge the cavitation region but has no effect on the acoustic pressure distribution pattern.The acoustic pressure ratio significantly affects the pressure distribution and the cavitation region,and the best cavitation effect is obtained at the ratio of 2:1(P15:P20).

关键词： dual-frequency ultrasonic numerical model acoustic pressure spatial interaction magnesium alloy

Theoretical study of the nonlinear force-loading control in single-molecule stretching experiments

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Communications in Theoretical Physics 2024年第4期76卷 167-175页

作者： Xingyu qi Zilong Guo Shimin le Hu Chen Research Institute for Biomimetics and Soft Matter Fujian Provincial Key Lab for Soft Functional Materials ResearchDepartment of PhysicsXiamen UniversityXiamen 361005China Center of Biomedical Physics Wenzhou InstituteUniversity of Chinese Academy of SciencesWenzhou 325000China

Force spectrum measurements with constant loading rates are widely used in single-molecule manipulation experiments to study the mechanical stability and force response of biomolecules.Force-dependent transition rates can be obtained from the transition force distribution,but it is limited to the force range with non-zero force distribution.Although constant loading rate control can be realized with magnetic tweezers,the loading rate range is limited due to the slow movement of permanent magnets.Non-linear exponential and exponential squared force loading functions are more feasible in magnetic tweezers,while there is no theoretical result available for these two kinds of non-linear force loading functions.In this study,we solved the unfolding process of a protein following Bell's model under nonlinear exponential and exponential squared force loading functions,which offer a broader range of unfolding force distribution compared to the traditional constant loading rate experiments.Furthermore,we derived two force loading functions,which can produce uniform unfolding force distribution.This research contributes fundamental equations for the analysis of experimental data obtained through single-molecule manipulation under nonlinear force loading controls,paving the way for the use of nonlinear force control in magnetic tweezer experiments.

关键词： single-molecule manipulation magnetic tweezers force loading transition rates force distribution

Enhancement of mechanical properties of GTAW joints for ZC63 magnesium alloy by post-weld heat treatment

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Journal of Materials Science & Technology 2024年第2期169卷 251-263页

作者： Weiyang Zhou qichi le Ye Shi qiyu Liao Tong Wang qi Zou Clodualdo Aranas Jr Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China Key Laboratory of Lightweight Structural Materials Liaoning ProvinceNortheastern UniversityShenyang 110819China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China Department of Mechanical Engineering University of New BrunswickFrederictonE3B 5A3New BrunswickCanada

To further improve the microstructure and mechanical properties of gas tungsten arc welded(GTAW)welded joints for ZC63 magnesium alloy,post-weld heat treatment is carried out.It is found that the majority of the MgZnCu phase in the fusion zone(FZ)is dissolved in theα-Mg matrix under suitable heat treatment conditions.The remainder is diffusely distributed as rods or granules at the grain bound-aries.The excessive heat treatment temperature(460℃)leads to abnormal grain growth(AGG)in the FZ.The substructure gradient between the abnormally grown grains and the surrounding small grains pro-vides the driving force for AGG.Meanwhile,the dissolution of the MgZnCu phase weakens the hindering effect of the second phase on grain boundary migration,setting the stage for AGG.In addition,the detri-mental impact of the continuous MgZnCu phase on the mechanical properties of the welded joint is also lessened by its dissolution.The ultimate tensile strength(UTS),yield strength(YS)and elongation(EL)of the welded joints are 255 MPa,119 MPa and 27.0%,respectively,under the post-weld heat treatment process of 440℃×12 h.The welding coefficient of the welded joint reaches 97.0%,satisfying the service criteria set forth by the mechanical properties of the welded joints.

关键词： GTAW FZ Heat treatment AGG Mechanical properties

Bidirectional Transformer with absolute-position aware relative position encoding for encoding sentences

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Frontiers of Computer Science 2023年第1期17卷 63-71页

作者： le qi Yu ZHANG Ting LIU School of Computer Science and Technology Harbin Institute of TechnologyHarbin 150001China

Transformers have been widely studied in many natural language processing (NLP) tasks, which can capture the dependency from the whole sentence with a high parallelizability thanks to the multi-head attention and the position-wise feed-forward network. However, the above two components of transformers are position-independent, which causes transformers to be weak in modeling sentence structures. Existing studies commonly utilized positional encoding or mask strategies for capturing the structural information of sentences. In this paper, we aim at strengthening the ability of transformers on modeling the linear structure of sentences from three aspects, containing the absolute position of tokens, the relative distance, and the direction between tokens. We propose a novel bidirectional Transformer with absolute-position aware relative position encoding (BiAR-Transformer) that combines the positional encoding and the mask strategy together. We model the relative distance between tokens along with the absolute position of tokens by a novel absolute-position aware relative position encoding. Meanwhile, we apply a bidirectional mask strategy for modeling the direction between tokens. Experimental results on the natural language inference, paraphrase identification, sentiment classification and machine translation tasks show that BiAR-Transformer achieves superior performance than other strong baselines.

关键词： Transformer relative position encoding bidirectional mask strategy sentence encoder

Renewable conversion of coal gangue to 13-X molecular sieve for Cd^(2+)-containing wastewater adsorption performance

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Rare Metals 2024年第2期43卷 702-710页

作者： le Kang Si-Fan Liu Da-Wei Yi Kai Wang Hui-Ling Du Hao-qi Huang Peng Chen College of Materials Science and Engineering Xi’an University of Science and TechnologyXi’an710054China School of Electrical Engineering Weihai Innovation Research InstituteQingdao UniversityQingdao266000China School of Metallurgy Northeastern UniversityShenyang110819China School of Materials and Chemical Engineering Tongren UniversityTongren554300China

Using coal gangue(CG)as raw material,a new type of all solid-waste-based 13-X molecular sieve material was controllably prepared by alkali fusion-hydrothermal method.The synthetic molecular sieve was used as a solid adsorbent to treat Cd^(2+)-containing wastewater,and its adsorption behavior on Cd^(2+)in aqueous solution was studied and analyzed.The microstructure and morphology of the molecular sieve were investigated by X-ray diffraction(XRD),field emission scanning electron microscopy(FESEM)and specific surface area analyzer.The results show that the synthesized 13-X molecular sieve has higher Brunauer–Emmett–Teller(BET)specific surface area with higher crystallinity and higher adsorption capacity for the heavy metal Cd^(2+).The adsorption process of Cd^(2+)by molecular sieve conforms to the Langmuir isotherm adsorption equation and Lagergren pseudo-second-order rate equation.Combined with thermodynamic calculation,it can be concluded that the adsorption process is physically monolayer,spontaneous and exothermic.In this study,a low-cost and naturally available synthesis method of 13-X molecular sieve is reported.Combined with its adsorption mechanism for Cd^(2+),it provides a feasible and general method for removing heavy metal ions from coal gangue and also provides a new way for the utilization of coal gangue with high added value.

关键词： Coal gangue Hydrothermal synthesis 13-X molecular sieve Adsorption Wastewater containing Cd^(2+)

Treatment with β-sitosterol ameliorates the effects of cerebral ischemia/reperfusion injury by suppressing cholesterol overload, endoplasmic reticulum stress, and apoptosis

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Neural Regeneration Research 2024年第3期19卷 642-649页

作者： Xiuling Tang Tao Yan Saiying Wang qingqing Liu qi Yang Yongqiang Zhang Yujiao Li Yumei Wu Shuibing Liu Yulong Ma le Yang Precision Pharmacy&Drug Development Center Department of PharmacyTangdu HospitalAir Force Medical UniversityXi’anShaanxi ProvinceChina Department of Clinical Pharmacy Jinling HospitalMedical School of Nanjing UniversityNanjingJiangsu ProvinceChina Department of Pharmacology School of PharmacyAir Force Medical UniversityXi’anShaanxi ProvinceChina Department of Anesthesiology The First Medical Center of Chinese PLA General HospitalBeijingChina Department of Anatomy Histology and Embryology and K.K.Leung Brain Research CentreAir Force Medical UniversityXi’anShaanxi ProvinceChina

β-Sitosterol is a type of phytosterol that occurs naturally in plants.Previous studies have shown that it has anti-oxidant,anti-hyperlipidemic,anti-inflammatory,immunomodulatory,and anti-tumor effects,but it is unknown whetherβ-sitosterol treatment reduces the effects of ischemic stroke.Here we found that,in a mouse model of ischemic stroke induced by middle cerebral artery occlusion,β-sitosterol reduced the volume of cerebral infarction and brain edema,reduced neuronal apoptosis in brain tissue,and alleviated neurological dysfunction;moreover,β-sitosterol increased the activity of oxygen-and glucose-deprived cerebral cortex neurons and reduced apoptosis.Further investigation showed that the neuroprotective effects ofβ-sitosterol may be related to inhibition of endoplasmic reticulum stress caused by intracellular cholesterol accumulation after ischemic stroke.In addition,β-sitosterol showed high affinity for NPC1L1,a key transporter of cholesterol,and antagonized its activity.In conclusion,β-sitosterol may help treat ischemic stroke by inhibiting neuronal intracellular cholesterol overload/endoplasmic reticulum stress/apoptosis signaling pathways.

关键词： apoptosis blood-brain barrier β-sitosterol cerebral ischemia/reperfusion injury cholesterol overload cholesterol transport endoplasmic reticulum stress ischemic stroke molecular docking NPC1L1

Mitochondrial Regulation of Macrophages in Innate Immunity and Diverse Roles of Macrophages During Cochlear Inflammation

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Neuroscience Bulletin 2024年第2期40卷 255-267页

作者： Yuan Zhang Fanglei Ye Xiaolong Fu Shen Li le Wang Yutian Chen Hongmin Li Shaojuan Hao Kun Zhao qi Feng Peipei Li Department of Otology The First Afliated Hospital of Zhengzhou UniversityZhengzhou 450052China Shandong Provincial Hospital Shandong First Medical UniversityJinan 250000China Department of Neurology The First Afliated Hospital of Zhengzhou UniversityZhengzhou 450052China The Department of Endovascular Surgery The First Afliated Hospital of Zhengzhou UniversityZhengzhou 450052China Department of Integrated Traditional and Western Nephrology The First Afliated Hospital of Zhengzhou UniversityZhengzhou 450052China Henan Province Research Center of Kidney Disease Zhengzhou 450052China

Macrophages are essential components of the innate immune system and constitute a non-specific first line of host defense against pathogens and inflammation.Mitochondria regulate macrophage activation and innate immune responses in various inflammatory diseases,including cochlear inflammation.The distribution,number,and morphological characteristics of cochlear macrophages change significantly across different inner ear regions under various pathological conditions,including noise exposure,ototoxicity,and age-related degeneration.However,the exact mechanism underlying the role of mitochondria in macrophages in auditory function remains unclear.Here,we summarize the major factors and mitochondrial signaling pathways(e.g.,metabolism,mitochondrial reactive oxygen species,mitochondrial DNA,and the inflammasome)that influence macrophage activation in the innate immune response.In particular,we focus on the properties of cochlear macrophages,activated signaling pathways,and the secretion of inflammatory cytokines after acoustic injury.We hope this review will provide new perspectives and a basis for future research on cochlear inflammation.

关键词： Macrophage Mitochondria Innate immunity Cochlea Infammation

Exosome-Transmitted miR-224-5p Promotes Colorectal Cancer Cell Proliferation via Targeting ULK2 in p53-Dependent Manner

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Biomedical and Environmental Sciences 2024年第1期37卷 71-84页

作者： YANG le Mei ZHENG qi LIU Xiao Jia LI Xian Xian Veronica Lim CHEN qi ZHAO Zhong Hua WANG Shu Yang Department of Pathology School of Basic MedicineFudan UniversityShanghai 200032China Department of Pathology Dunedin School of MedicineUniversity of OtagoDunedin 9054New Zealand Department of Pathology Huashan HospitalFudan UniversityShanghai 200040China Shanghai Cancer Institute Renji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200127China Teladoc Health Inc Shanghai 200335China Shanghai Medical College Fudan UniversityShanghai 200032China Shanghai Key Laboratory of Medical Imaging Computing and Computer Assisted Intervention Shanghai 200032China

Objective To investigate the role and molecular mechanism of exosomal miR-224-5p in colorectal cancer(CRC).Methods The miR-224-5p expression in CRC patient tissues and cell-derived exosomes was measured by laser capture microdissection and qRT-PCR,respectively.Dual-luciferase reporter gene assay was used to determine the target gene of miR-224-5p.The protein expressions of p53 and unc-51 like kinase 2(ULK2)in CRC cells were detected by western blot.Flow cytometry was used to detect cell cycle and apoptosis.Cell proliferation was measured by CCK8 and EdU assay.Results The miR-224-5p expression was upregulated in CRC tissues and increased progressively with the rise of CRC stage.CRC cells secreted extracellular miR-224-5p mainly in an exosome-dependent manner,and then miR-224-5p could be transferred to surrounding tumor cells to regulate cell proliferation in the form of autocrine or paracrine.Moreover,ULK2 was characterized as a direct target of miR-224-5p and was downregulated in CRC tissues.Interestingly,ULK2 inhibited CRC cell proliferation in a p53-dependent manner.Furthermore,exosome-derived miR-224-5p partially reversed the proliferation regulation of ULK2 on CRC cells.Conclusion Our findings demonstrate that exosome-transmitted miR-224-5p promotes p53-dependent cell proliferation by targeting ULK2 in CRC,which may offer promising targets for CRC prevention and therapy.

关键词： miR-224-5p Exosome ULK2 p53 Cell proliferation Colorectal cancer

Decreased human leukocyte antigen-D-related expression on CD14^(+)monocytes in patients with out-of-hospital cardiac arrest provided target temperature management therapy:a prospective observational study

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Emergency and Critical Care Medicine 2024年第1期4卷 16-21页

作者： Huan Shao Wei Yuan Ziren Tang Zhijiang qi le An qiang Zhang Chunsheng Li Department of Emergency Medicine Beijing Chao-Yang HospitalCapital Medical UniversityBeijingChina Beijing Key Laboratory of Cardiopulmonary Cerebral Resuscitation Beijing Chao-Yang HospitalCapital Medical UniversityBeijingChina.

Background:Post–cardiac arrest syndrome involves systemic inflammation,which causes subsequent neurological impairments.We investigated the influence of targeted temperature management(TTM)therapy in patients with out-of-hospital cardiac arrest(OHCA)after return of spontaneous circulation(ROSC)by observing the changes in circulating CD14^(+)monocytes and the expression of human leukocyte antigen D–related(HLA-DR)and programmed cell death ligand 1(PD-L1)in CD14^(+)monocytes.Methods:Adult patients admitted to the emergency department of Beijing Chao-Yang Hospital after OHCA between January 2017 and March 2018 were included in this study.Thirty control subjects,10 patients with OHCA,and 37 patients with OHCA who received 72 hours of TTM therapy were enrolled.Peripheral blood samples of patients in the OHCA and TTM groups were collected on Days 1 and 3(D1 and D3)after ROSC and evaluated for HLA-DR and PD-L1 expression on CD14^(+)monocytes using flow cytometry.Results:Compared with control subjects,the percentage of circulating CD14^(+)monocytes,HLA-DR+/CD14^(+)monocyte ratios,and mean fluorescence intensity were significantly decreased in patients with OHCA.After ROSC,HLA-DR expression in CD14^(+)monocytes in the TTM group was lower than that in patients with OHCA.However,there were no significant differences in the percentage of PD-L1+/CD14^(+)monocytes or the mean fluorescence intensity between patients with OHCA and healthy volunteers.Conclusion:After ROSC,circulating CD14^(+)monocytes and HLA-DR+/CD14^(+)monocyte ratios decreased significantly in patients with OHCA.Human leukocyte antigen D–related expression in CD14^(+)monocytes was lower in patients treated with TTM.

关键词： Human leukocyte antigen D-related Monocytes Out-of-hospital cardiac arrest Target temperature management