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Neural Regeneration Research 2012年第3期7卷 229-234页

作者： gang guo yonggui yang weiqun yang Department of Radiology Xiamen Second Hospital Teaching Hospital of Fujian Medical University Xiamen 361021 Fujian Province China

We performed a retrospective analysis of non-contrast computed tomography （CT） scans, immediately subsequent magnetic resonance imaging （MRI）, and cerebral angiography data from 30 consecutive patients with acute ischemic stroke within 6 hours after symptom onset. Results showed that eleven patients developed subsequent hemorrhagic transformation at follow-up. A hyperintense middle cerebral artery sign on MRI was found in six hemorrhagic patients, all of who had acute thrombosis formation on magnetic resonance angiography and digital subtraction angiography. No patients in the non-hemorrhagic group had hyperintense middle cerebral artery sign on MRI. The sensitivity, specificity, and positive predictive values of the hyperintense middle cerebral artery sign on MRI T1-weighted image for subsequent hemorrhagic transformation were 54.5%, 100%, and 100% respectively. Hyperdense middle cerebral artery sign on non-contrast CT was observed in nine patients, five of who developed hemorrhagic transformation. These data suggest that hyperintense middle cerebral artery sign on MRI T1-weighted image is a highly specific and moderately sensitive indicator of subsequent hemorrhagic transformation in patients after acute ischemic stroke, and its specificity is superior to CT.

关键词： stroke hemorrhagic transformation magnetic resonance imaging angiography

Cerebral blood flow volume measurements of the carotid artery and ipsilateral branches using two-dimensional phase-contrast magnetic resonance angiography

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Neural Regeneration Research 2011年第30期6卷 2367-2371页

作者： gang guo yonggui yang weiqun yang Department of Radiology Xiamen Second Hospital Teaching Hospital of Fujian Medical University Xiamen 361021 Fujian Province China

The optimal velocity encoding of phase-contrast magnetic resonance angiography （PC MRA） in measuring cerebral blood flow volume （BFV） ranges from 60 to 80 cm/s. To verify the accuracy of two-dimensional （2D） PC MRA, the present study localized the region of interest at blood vessels of the neck using PC MRA based on three-dimensional time-of-flight sequences, and the velocity encoding was set to 80 cm/s. Results of the measurements showed that the error rate was 7.0±6.0% in the estimation of BFV in the internal carotid artery, the external carotid artery and the ipsilateral common carotid artery. There was no significant difference, and a significant correlation in BFV between internal carotid artery ＋ external carotid artery and ipsilateral common carotid artery. In addition, the BFV of the common carotid artery was correlated with that of the ipsilateral internal carotid artery. The main error was attributed to the external carotid artery and its branches. Therefore, after selecting the appropriate scanning parameters and protocols, 2D PC MRA is more accurate in the determination of BFV in the carotid arteries.

关键词： two-dimensional phase-contrast magnetic resonance angiography blood flow three-dimensional time-of-flight phase-contrast magnetic resonance angiography internal carotid artery common carotid artery external carotid artery velocity encoding

Optimal velocity encoding during measurement of cerebral blood flow volume using phase-contrast magnetic resonance angiography

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Neural Regeneration Research 2011年第23期6卷 1796-1800页

作者： gang guo yonggui yang weiqun yang Department of Radiology Xiamen Second Hospital Teaching Hospital of Fujian Medical University Xiamen 361021 Fujian Province China

This study investigated the effect of velocity encoding on measurement of brain blood flow and blood volume of inflow and outflow using phase-contrast magnetic resonance angiography. A single two-dimensional phase-contrast magnetic resonance angiography slice was applied perpendicular to the internal carotid artery and the vertebral artery at C2 level. For each subject, the velocity encoding was set from 30 to 90 cm/s with an interval of 10 cm/s for a total of seven settings. Various velocity encodings greatly affected blood flow volume, maximal blood flow velocity and mean blood flow velocity in the internal carotid artery, but did not significantly affect vertebral arteries and jugular veins. When velocity encoding was 60-80 cm/s, the inflow blood volume was 655 _＋ 118 mL/min, and the outflow volume was 506 _＋ 186 mL/min. The ratio of outflow/inflow was steady at 0.78-0.83, and there was no aliasing in any of the images. These findings suggest that velocity encodings of 60 80 cm/s should be selected during measurement of cerebral blood flow volume using phase-contrast magnetic resonance angiography.

关键词： cerebral blood flow velocity encoding phase-contrast magnetic resonance imaging

Effect of pouring time on microstructure and mechanical properties of centrifugal cast Ti-46Al alloy tubes

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China Foundry 2025年

作者： gang Huang Qian Dang Cong-cong Su Jing Zhao Chi Zhang guo-huai Liu Zhao-dong Wang The State Key Laboratory of Rolling and Automation Northeastern University School of Materials Science and Engineering Shenyang University of Technology

The grain size of TiAl alloy castings prepared by traditional casting process is coarse, thus showing poor mechanical properties. In this study, a new type of high performance Ti-46Al alloy tube prepared by vacuum centrifugal casting technology was introduced. This research comprehensively examined the influence of pouring time on the microstructure and mechanical performance of the castings, employing both experimental approaches and ProCast simulation methodologies. The findings indicate that prolonging the pouring time facilitates a microstructural evolution from coarse columnar grains to refined equiaxed grains. Under the condition of pouring temperature of 1,600 °C, rotation speed of 800 r·min-1and pouring time of 6 s, the tensile strength of Ti-46Al alloy at room temperature reaches 650 MPa, and the tensile strength at 800 °C reaches 705 MPa, which is significantly higher than that of traditional as-cast Ti-Al alloy.

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基于质谱的脂质C=C和脂肪酰基位置鉴定方法及其在食品分析中的应用研究进展

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食品科学 2025年第1期46卷 293-303页

作者：滕蒙南段晓亮张东郭伟群浙江农林大学食品与健康学院浙江杭州311302 国家粮食和物资储备局科学研究院北京102629

脂质在生命体中发挥着重要作用,结构影响功能,脂质精细结构解析至关重要。但脂质结构的多样性和相似性对脂质分析提出了巨大挑战。质谱是脂质分析的重要技术之一,在脂质C=C和脂肪酰基位置结构解析中有着较好的应用。本文介绍脂质分析的... 详细信息

脂质在生命体中发挥着重要作用,结构影响功能,脂质精细结构解析至关重要。但脂质结构的多样性和相似性对脂质分析提出了巨大挑战。质谱是脂质分析的重要技术之一,在脂质C=C和脂肪酰基位置结构解析中有着较好的应用。本文介绍脂质分析的前处理方法,综述基于质谱的C=C位置和脂肪酰基位置鉴定方法,并讨论该方法在食品分析中的应用,最后展望质谱在脂质化合物精确结构解析方面的发展趋势,以期为不饱和脂质C=C位置和脂肪酰基位置鉴定以及异构体识别和定量分析技术发展和应用提供参考。

关键词：脂质质谱 C=C位置脂肪酰基位置应用

BEESO:Multi-strategy Boosted Snake-Inspired Optimizer for Engineering Applications

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Journal of Bionic Engineering 2023年第4期20卷 1791-1827页

作者： gang Hu Rui yang Muhammad Abbas guo Wei Department of Applied Mathematics Xi’an University of TechnologyXi’an710054China School of Computer Science and Engineering Xi’an University of TechnologyXi’an710048China Department of Mathematics University of SargodhaSargodha40100Pakistan University of North Carolina at Pembroke PembrokeNC28372USA

This paper presents an efficient enhanced snake optimizer termed BEESO for global optimization and engineering *** a newly mooted meta-heuristic algorithm,snake optimizer(SO)mathematically models the mating characteristics of snakes to find the optimal *** has a simple structure and offers a delicate balance between exploitation and ***,it also has some shortcomings to be *** proposed BEESO consequently aims to lighten the issues of lack of population diversity,convergence slowness,and the tendency to be stuck in local optima in *** presentation of Bi-Directional Search(BDS)is to approach the global optimal value along the direction guided by the best and the worst individuals,which makes the convergence speed *** increase in population diversity in BEESO benefits from Modified Evolutionary Population Dynamics(MEPD),and the replacement of poorer quality individuals improves population *** Elite Opposition-Based Learning(EOBL)provides improved local exploitation ability of BEESO by utilizing solid solutions with good *** performance of BEESO is illustrated by comparing its experimental results with several algorithms on benchmark functions and engineering ***,the results of the experiment are analyzed again from a statistical point of view using the Friedman and Wilcoxon rank sum *** findings show that these introduced strategies provide some improvements in the performance of SO,and the accuracy and stability of the optimization results provided by the proposed BEESO are competitive among all *** conclude,the proposed BEESO offers a good alternative to solving optimization issues.

关键词： Snake optimizer Bi-Directional Search Evolutionary Population Dynamics Elite Opposition-Based Learning Strategy Mechanical optimization design

Maintaining moderate levels of hypochlorous acid promotes neural stem cell proliferation and differentiation in the recovery phase of stroke

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Neural Regeneration Research 2025年第3期20卷 845-857页

作者： Lin-Yan Huang Yi-De Zhang Jie Chen Hai-Di Fan Wan Wang Bin Wang Ju-Yun Ma Peng-Peng Li Hai-Wei Pu Xin-Yian guo Jian-gang Shen Su-Hua Qi School of Medical Technology Xuzhou Key Laboratory of Laboratory DiagnosticsXuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Pharmacy Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina Department of Laboratory Medicine Branch Hospital of Huai’an First People’s HospitalHuai’anJiangsu ProvinceChina Department of Laboratory Medicine the Affiliated Hospital of Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Chinese Medicine The University of Hong KongHong Kong Special Administrative RegionChina

It has been shown clinically that continuous removal of ischemia/reperfusion-induced reactive oxygen species is not conducive to the recovery of late ***,previous studies have shown that excessive increases in hypochlorous acid after stroke can cause severe damage to brain *** previous studies have found that a small amount of hypochlorous acid still exists in the later stage of stroke,but its specific role and mechanism are currently *** simulate stroke in vivo,a middle cerebral artery occlusion rat model was established,with an oxygen-glucose deprivation/reoxygenation model established in vitro to mimic *** found that in the early stage(within 24 hours)of ischemic stroke,neutrophils produced a large amount of hypochlorous acid,while in the recovery phase(10 days after stroke),microglia were activated and produced a small amount of hypochlorous ***,in acute stroke in rats,hypochlorous acid production was prevented using a hypochlorous acid scavenger,taurine,or myeloperoxidase inhibitor,4-aminobenzoic acid *** results showed that high levels of hypochlorous acid(200μM)induced neuronal apoptosis after oxygen/glucose deprivation/***,in the recovery phase of the middle cerebral artery occlusion model,a moderate level of hypochlorous acid promoted the proliferation and differentiation of neural stem cells into neurons and *** suggests that hypochlorous acid plays different roles at different phases of cerebral ischemia/reperfusion *** levels of hypochlorous acid(5 and 100μM)promoted nuclear translocation ofβ-*** transfection of single-site mutation plasmids,we found that hypochlorous acid induced chlorination of theβ-catenin tyrosine 30 residue,which promoted nuclear ***,our study indicates that maintaining low levels of hypochlorous acid plays a key role in the recovery of neurological function.

关键词： cell differentiation cerebral ischemia/reperfusion injury chlorination hypochlorous acid microglia neural stem cell neurogenesis nuclear translocation stroke β-catenin

Bio-inspired Filter Design Based on Vortex Control Mechanism of Parallel Groove Structure

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Journal of Bionic Engineering 2023年第1期20卷 338-348页

作者： Yawei Zhu Dean Hu Yonggang guo Hao Ding gang yang School of Mechanical and Electrical Engineering Henan University of TechnologyZhengzhou450001China Key Laboratory of Advanced Design and Simulation Techniques for Special Equipments Ministry of EducationHunan UniversityChangsha410082China

Solid–liquid separation is widely used in daily life and practical *** industrial filters are prone to clogging,but this rarely occurs in filter-feeding *** by the filter feeding mechanism of balaenid whales and considering the local grooves in the fringes layer,a new bionic filter is produced by 3D printing technology through the bionic design of the parallel channels inside the mouth of balaenid *** the same time,a test platform composed of the bionic filter,peristaltic pump,fluid pulse rectifier and water tank is built to carry out the fluid flow pattern dyeing and particle filtration *** is found that fluid separation occurs near the groove structure and local vortices are *** vortex control filtration mechanism makes the particles in the front grooves tend to accumulate on the left side,which has a certain anti-clogging ***,the increase of flow velocity leads to the enhancement of vortices,which makes the accumulation effect on the left more *** study initially practices the bionic application from biological model to engineering design,and the vortex control anti-clogging filtration mechanism proposed in the study has a wide range of application prospects and values.

关键词： Solid-liquid separation Balaenid whales Filter feeding-Bionic design Anti-clogging filtration mechanism

T-Splines Based Isogeometric Topology Optimization with Arbitrarily Shaped Design Domains

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Computer Modeling in Engineering & Sciences 2020年第6期123卷 1033-1059页

作者： gang Zhao Jiaming yang Wei Wang yang Zhang Xiaoxiao Du Mayi guo School of Mechanical Engineering and Automation Beihang UniversityBeijing100191China Beijing Engineering Technological Research Center of High-Efficient&Green CNC Machining Process Beijing100191China

In this paper,a new isogeometric topology optimization(ITO)method is proposed by using T-splines based isogeometric analysis(IGA).The arbitrarily shaped design domains,directly obtained from CAD,are represented by a single T-spline surface which overcomes the topological limitations of Non-Uniform Rational B-Spline(NURBS).The coefficients correlated with control points are directly used as design ***,the T-spline basis functions applied for geometry description and calculation of structural response are simultaneously introduced to represent the density *** numerical examples show that the proposed approach leads to a coherent workflow to handle design problems of complicated *** optimized results are free of checkerboard patterns without additional stabilization and filtering techniques due to the properties of T-splines,which also simplified the *** addition,through performing local refinement,we can easily achieve multiresolution optimization and infill optimization within the T-splines based *** general,the proposed method provides a possibility to design,analyze,and optimize engineering structures in a uniform model,which has the potential to improve design efficiency and reduce the cost of product development.

关键词： Topology optimization isogeometric analysis unstructured T-splines Bézier extraction

Multiple Dens Evaginatus of Premolars and Molars in Chinese Dentition:A Case Report and Literature Review

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International Journal of Oral Science 2010年第3期2卷 177-180页

作者： Yan-gang Rao Li-yang guo Tao Hu Department of Operative Dentistry and Endodontics West China College of Stomatology Sichuan University ChengduChina

Dens evaginatus （DE） is a dental anomaly that occurs as an accessory tubercle on the occlusal or lingual surface of a tooth. The authors provide a literature review and report a rare case in which DE occurs on multiple mandibular premolars and maxillary molars. The patient is a 26-year-old Chinese woman, with a chief complaint of gingival bleeding. DE affecting teeth 17, 27, 35,and 45 was found during clinical examination. For treatment of the patient, we reduced the opposing occluding teeth, while undertaking progressive grinding of the tubercles for six months. We followed-up for a year. This suggests the importance of examining for multiple DE during clinical practice.

关键词： Dens evaginatus evaginated odontome molar,premolar