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Using shapes correlation for active contour segmentation of uterine fibroid ultrasound images in computer-aided therapy

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Applied Mathematics(A Journal of Chinese Universities) 2016年第1期31卷 37-52页

作者： NI Bo HE Fa-zhi PAN Yi-teng yuan zhi-yong School of Computer Science Wuhan University School of Computer Science Hubei Polytechnic University

Segmenting the lesion regions from the ultrasound （US） images is an important step in the intra-operative planning of some computer-aided therapies. High-Intensity Focused Ultrasound （HIFU）, as a popular computer-aided therapy, has been widely used in the treatment of uterine fibroids. However, such segmentation in HIFU remains challenge for two reasons：（1） the blurry or missing boundaries of lesion regions in the HIFU images and （2） the deformation of uterine fibroids caused by the patient＇s breathing or an external force during the US imaging process, which can lead to complex shapes of lesion regions. These factors have prevented classical active contour-based segmentation methods from yielding desired results for uterine fibroids in US images. In this paper, a novel active contour-based segmentation method is proposed, which utilizes the correlation information of target shapes among a sequence of images as prior knowledge to aid the existing active contour method. This prior knowledge can be interpreted as a unsupervised clustering of shapes prior modeling. Meanwhile, it is also proved that the shapes correlation has the low-rank property in a linear space, and the theory of matrix recovery is used as an effective tool to impose the proposed prior on an existing active contour model. Finally, an accurate method is developed to solve the proposed model by using the Augmented Lagrange Multiplier （ALM）. Experimental results from both synthetic and clinical uterine fibroids US image sequences demonstrate that the proposed method can consistently improve the performance of active contour models and increase the robustness against missing or misleading boundaries, and can greatly improve the efficiency of HIFU therapy.

关键词： Active contour shapes correlation ultrasound image segmentation matrix recovery computer-aided therapy.

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Soil organic carbon contents, aggregate stability,and humic acid composition in different alpine grasslands in Qinghai-Tibet Plateau

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Journal of Mountain Science 2016年第11期13卷 2015-2027页

作者： CAO zhi-yuan WANG yong LI Jie ZHANG Jin-jing HE Nian-peng Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Alpine grassland soils on Qinghai-Tibet Plateau store approximately 33.5 Pg of organic carbon(C) at 0–0.75 m depth and play an important role in the global carbon *** investigated soil organic C(SOC),water-soluble organic C(WSOC),easily oxidizable organic C(EOC),humic C fractions,aggregate-associated C,aggregate stability,and humic acid(HA) composition along an east-west transect across Qinghai-Tibet Plateau,and explored their spatial patterns and controlling *** contents of SOC,WSOC,EOC,humic C fractions and aggregate-associated C,the proportions of macroaggregates(2-0.25) and micro-aggregates(0.25-0.053 mm),and the aggregate stability indices all increased in the order alpine desert < alpine steppe < alpine *** alkyl C,O-alkyl C,and aliphatic C/aromatic C ratio of HA increased as alpine desert < alpine meadow < alpine steppe,and the trends were reverse for the aromatic C and HB/HI *** annual precipitation and aboveground biomass weresignificantly correlated with the contents of SOC and its fractions,the proportions of macro- and microaggregates,and the aggregate stability indices along this *** all these C fractions,SOC content and aggregate stability were more closely associated with humic C and silt and clay sized C in comparison with WSOC,EOC,and macro- and microaggregate *** results suggested that alpine meadow soils containing higher SOC exhibited high soil aggregation and aggregate *** annual precipitation should be the main climate factor controlling the spatial patterns of SOC,soil aggregation,and aggregate stability in this *** resistant and stable C fractions rather than labile C fractions are the major determinant of SOC stocks and aggregate stability.

关键词： Soil organic carbon Aggregate stability Humic acid Carbon-13 nuclear magnetic resonance Latitudinal transect Qinghai-Tibet Plateau

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多级维修供应下可修复备件库存建模与优化

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系统工程理论与实践 2013年第10期33卷 2623-2630页

作者：罗祎阮旻智袁志勇海军工程大学兵器工程系武汉430033

为了研究可修复备件库存分配模型,根据METRIC理论,结合"原位维修率"、"占空比"、"重测完好率"等重要维修参数,建立了具有多等级的维修供应体系、多层次结构备件的初始库存分配通用模型.以装备可用度、备件满足率以及保障延误时间为指标... 详细信息

为了研究可修复备件库存分配模型,根据METRIC理论,结合"原位维修率"、"占空比"、"重测完好率"等重要维修参数,建立了具有多等级的维修供应体系、多层次结构备件的初始库存分配通用模型.以装备可用度、备件满足率以及保障延误时间为指标,保障费用为约束,对备件库存方案进行优化,通过实例给出了优化结果,分析了影响备件库存分配方案的保障性因素,并通过VMETRIC仿真平台对模型结果进行了检验.结果表明:本文模型得到的优化方案与VMETRIC软件运行结果一致,证明了本文模型的正确性和算法的合理性.

关键词：可修复备件多级维修供应 METRIC模型边际优化库存配置

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Brain metastasis treated with Cyberknife

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Chinese Medical Journal 2009年第16期122卷 1847-1850页

作者： WANG zhi-zhen yuan zhi-yong ZHANG Wen-cheng YOU Jin-qiang WANG Ping Key Laboratory of Cancer Prevention and Therapy and Department of Radiation Therapy Tianjin Cancer Hospital of Tianjin Medical University Tianjin 300060 China

Background Cyberknife can greatly raise the fractional dose of stereotactic radiosurgery, thus improving its clinical efficacy. We retrospectively analyzed clinical outcomes of brain metastasis treated with Cyberknife. Methods We analyzed 40 cases of brain metastases treated with Cyberknife in the Tianjin Cancer Hospital from August 1, 2006 to August 1, 2007, for a total of 68 lesions with maximal diameter of 0.4-7.5 cm （average 1.88 cm）. Total hypofractional radiated dosage was 18-36 Gy （5-25 Gy/F, 1-5 F） by Cyberknife. We evaluated the remission rate of clinical symptoms, correlation factors to new foci, 3-month local control rates, and 3-month and 1-year survival rates. All patients were followed up for more than 14 months. Results After 1 week, clinical remission was 90.0% （36/40）. After 3 months, the local control rate and therapeutic effective rate were 77.9% （53/68） and 94.1% （64/68）, respectively, as observed by cranium augmentation CT or MRI. The three-month, six-month and 1-year survival rates were 97.5% （39/40）, 82.5% （33/40） and 67.5% （27/40）, respectively. Fourteen patients had neopathy outside the original lesion after 3 months. Neopathy was not correlated with age, whole-brain radiotherapy, number of original lesions, maximum diameter of the original lesion, therapeutic dose per fraction, therapeutic frequency or total therapeutic dose. Conclusions Cyberknife got perfect clinical outcomes by higher dosage per fraction. It is an appropriate and valid treatment shortcut for brain metastasis.

关键词： Cyberknife brain tumor metastasis clinical practice whole brain radiotherapy

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Basic research of the relationship between irradiation dose and volume in radiation-induced pulmonary injury

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Chinese Medical Journal 2009年第16期122卷 1929-1934页

作者： PANG Qing-song WANG Ping WANG Jing WANG Wei WANG Jun yuan zhi-yong Department of Radiotherapy Diagnosis and Treatment Center of Lung Cancer Cancer Hospital of Tianjin Medical University Tianjin 300060 China

Background Irradiation dose and volume are the major investigated the relationships between the irradiation dose model of graded volume irradiation of the rat lung. physical factors of radiation-induced lung injury. The study and volume in radiation-induced lung injury by setting up a Methods Animals were randomly assigned to three groups. The ELEKTA precise 2.03 treatment plan system was applied to calculate the irradiation dose and volume. The treatment plan for the three groups was： group I received a ＂high dose to a small volume＂（25% volume group） with the mean irradiation volume being 1.748 cm^3 （25% lung volume）; the total dose and mean lung dose （MLD） were 4610 cGy and 2006 cGy, respectively （bilateral AP-PA fields, source to axis distance （SAD） = 100 cm, 6MVX, single irradiation）; Group 2 received a ＂low dose to a large volume＂（100% volume group） with the mean irradiation volume being 6.99 cm^3 （100% lung volume）; the total dose was 1153 cGy. MLD was 2006 cGy, which was the same as that of group 1 （bilateral AP-PA fields, SAD = 100 cm, 6MVX, single irradiation）; Group 3 was a control group. With the exception of receiving no irradiation, group 3 had rest steps that were the same as those of the experimental groups. After irradiation, functional, histopathological, and CT changes were compared every two weeks till the 16th week. Results Functionally, after irradiation breath rate （BR） increases were observed in both group 1 and group 2, especially during the period of 6th-8th weeks. The changes of BR in the 100% volume group were earlier and faster. For the 25% volume group, although pathology was more severe, hardly any obvious increase in BR was observed. Radiographic changes were observed during the early period （the 4th week） and the most obvious changes manifested during the mediated period （the 8th week）. The extensiveness of high density and the decreased lung permeability were presented in the 100% volume group, and ground glass opacity and patchy c

关键词： radiation-induced pulmonary injury dose volume

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Effect of initial microstructure on microstructure evolution and mechanical properties of 0.12C martensitic steels during quenching and tempering

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Journal of Iron and Steel Research International 2025年第1期32卷 260-269页

作者： Ya-ru Wang Zi-yong Hou He Yang Jun Zhao zhi-yuan Chang Fan-mao Meng Ling Zhang Gui-lin Wu Xiao-xu Huang State Key Laboratory of Vanadium and Titanium Resource Comprehensive Utilization Panzhihua 617000SichuanChina State Key Laboratory of Advanced Special Steel Shanghai Key Laboratory of Advanced FerrometallurgySchool of Materials Science and EngineeringShanghai UniversityShanghai 200444China International Joint Laboratory for Light Alloys(Ministry of Education) College of Materials Science and EngineeringChongqing UniversityChongqing 400044China Institute of Steel Technology for Automobile and Household Appliance Pangang Group Co.Ltd.Panzhihua 617000SichuanChina ATB Motor(Shanghai)Co. Ltd.Keen International CenterShanghai 200041China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China

The microstructure evolution and mechanical properties of a Fe-0.12C-0.2Si-1.6Mn-0.3Cr-0.0025B(wt.%)steel with different initial microstructures,i.e.,hot rolled(HR)and cold rolled-annealed(CRA),were studied through optical microscopy,scanning electron microscopy,electron channeling contrast imaging,microhardness and room temperature uniaxial tensile *** water quenching from 930℃ to room temperature,a fully martensitic microstructure was obtained in both as-quenched HR and CRA specimens,which shows a microhardness of 480±5 HV,and no significant difference in microstructure and microhardness was *** test results show that the product of tensile strength and total elongation(UTS×TE)of the as-quenched HR specimen,i.e.,24.1 GPa%,is higher than that of the as-quenched CRA specimen,i.e.,18.9 GPa%.While,after being tempered at 300℃,the martensitic microstructures and mechanical properties of the two as-quenched specimens change significantly due to the synergy role of the matrix phase softening and the precipitation *** the maximum UTS×TE,it is 18.9 GPa%obtained in the as-quenched CRA one,while that is 24.4 GPa%obtained in the HR specimen after tempered at 300℃ for 5 min.

关键词： Initial microstructure Lath martensite Quenching Tempering Mechanical property

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Impact of triglyceride-glucose index on the long-term prognosis of advanced gastric cancer patients receiving immunotherapy combined with chemotherapy

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World Journal of Gastroenterology 2025年第5期31卷 68-83页

作者： zhi-yuan Yao Xiao Ma yong-Zheng Cui Jie Liu Zheng-Xiang Han Jun Song Department of Oncology The Affiliated Hospital of Xuzhou Medical CollegeXuzhou 221000Jiangsu ProvinceChina Department of Oncology The Second Affiliated Hospital of Nanjing Medical UniversityNanjing 210008Jiangsu ProvinceChina Department of Radiotherapy The Affiliated Hospital of Xuzhou Medical CollegeXuzhou 221000Jiangsu ProvinceChina Department of Gastrointestinal Surgery The Affiliated Hospital of Xuzhou Medical CollegeXuzhou 221000Jiangsu ProvinceChina

BACKGROUND Gastric cancer(GC)is the fifth most common malignancy and the third leading cause of death *** advancements in immunotherapies,patient prognosis remains poor,necessitating the identification of key prognostic factors to optimize the treatment *** resistance,as indicated by the triglyceride glucose(TyG)index,is increasingly recognized for its impact on cancer progression and immune modulation,and its potential role in GC prognosis is of particular *** To investigate whether the TyG index,a surrogate marker of insulin resistance,can predict the prognosis of patients with advanced GC receiving immunotherapy combined with *** This retrospective study included 300 patients with advanced GC who received sintilimab combined with *** patients were categorized into two groups according to high or low TyG index,and independent prognostic factors for overall survival(OS)were determined using Cox proportional hazards regression analysis,which led to the development of a nomogram *** Of the included patients,136 had a high TyG index and 164 had a low TyG *** median progression-free survival of the high TyG index group was significantly longer than that of the low TyG index ***,the median OS of the high TyG index group was significantly longer than that of the low TyG index *** ob-jective response and disease control rates in the two groups were 18.38%vs 9.15%and 58.82%vs 46.95%,*** significant difference was noted in the incidence of adverse reactions at any level between the two groups(P>0.05).In multivariate analysis,the Eastern Cooperative Oncology Group score,programmed cell death ligand 1 expression,and TyG index acted as independent prognostic factors for *** these factors,the hazard ratio of the TyG index was 0.36(95%confidence interval:0.36-0.55,P<0.001),and the nomogram model re-emphasized its importance as the main predictor of patient prognos

关键词： Triglyceride glucose index Gastric cancer Sintilimab Prognostic model Efficacy Safety

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多基地声呐接收机最优布阵的探讨

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兵工学报 2008年第3期29卷 287-290页

作者：顾晓东邱志明袁志勇海军工程大学兵器工程系湖北武汉430033 海军装备研究院系统所北京100073

研究基于多声呐基阵的无源时差定位方法,从测时差定位原理入手,对定位误差与布阵几何的关系进行了分析,提出声呐基阵的最优布阵原则,对各布阵形式的定位精度进行仿真实验,给出最优布阵形式,仿真结果表明,该布阵形式在无源定位系统中有... 详细信息

研究基于多声呐基阵的无源时差定位方法,从测时差定位原理入手,对定位误差与布阵几何的关系进行了分析,提出声呐基阵的最优布阵原则,对各布阵形式的定位精度进行仿真实验,给出最优布阵形式,仿真结果表明,该布阵形式在无源定位系统中有很好的应用价值。

关键词：海洋测绘声呐时差定位最优布阵

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基于辅助变量法的双基阵纯方位目标跟踪算法

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系统工程与电子技术 2010年第3期32卷 508-511页

作者：顾晓东袁志勇邱志明海军工程大学兵器工程系湖北武汉430033 海军装备研究院系统所北京100073

伪线性估计算法是主要的纯方位目标跟踪算法之一,其计算简单,但估计结果严重有偏。针对伪线性估计算法估计的有偏性,提出了一种新的辅助变量方法对双基阵纯方位跟踪性能进行改进。该算法将上一时刻的目标估计值进行一次Levenberg-Marqua... 详细信息

伪线性估计算法是主要的纯方位目标跟踪算法之一,其计算简单,但估计结果严重有偏。针对伪线性估计算法估计的有偏性,提出了一种新的辅助变量方法对双基阵纯方位跟踪性能进行改进。该算法将上一时刻的目标估计值进行一次Levenberg-Marquardt迭代而得到的估计值作为辅助变量,进而对目标参数进行加权的最小二乘估计。通过仿真说明了利用该方法在不同的测量环境噪声下所得到的位置、速度跟踪误差曲线能快速地逼近CRLB,比双基阵EKF滤波器及伪线性估计算法有着更好的收敛速度和跟踪精度,证明了该方法的有效性。

关键词：双基阵纯方位伪线性估计辅助变量法无偏估计

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Trigonelline exerts its neuroprotective effects in experimental spinal cord injury through modulation of inflammation, apoptosis, and neurotrophic factors

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Asian Pacific Journal of Tropical Biomedicine 2025年第1期15卷 34-42页

作者： zhi-Lan Ye yuan Cao Department of Rehabilitation Jingdezhen Hospital of Traditional Chinese MedicineJingdezhen333000China Department of Neurosurgery General Hospital of Northern Theater CommandShenyang110000China

Objective:To assess the protective effects of trigonelline against spinal cord injury(SCI)in ***:Rats(Sprague-Dawley,male)were randomly assigned to seven groups(n=15 per group):normal,sham,SCI control(1%DMSO),methylprednisolone(30 mg/kg),and trigonelline(50,100,and 200 mg/kg).Rats received respective treatment daily for 28 *** was induced by using a temporary aneurysm ***,biochemical,and histological analyses were performed to investigate the neuroprotective effect of ***:Trigonelline(100 and 200 mg/kg)treatment effectively(P<0.05)mitigated SCI-induced changes in mechano-tactile sensation,allodynia,hyperalgesia,and motor nerve conduction *** notably(P<0.05)downregulated apoptotic(Bax and caspase-3)and inflammatory(COX-Ⅱ)markers,while upregulating Bcl-2 and BDNF mRNA expression in the spinal cord(P<0.05).Furthermore,trigonelline effectively alleviated(P<0.05)SCI-induced alterations in mitochondrial complex levels,resulting in enhanced nicotinamide adenine dinucleotide dehydrogenase,succinate dehydrogenase,redox activity,and cytochrome-C *** examination of spinal cord tissue indicated that trigonelline significantly(P<0.05)ameliorated the histological damage caused by SCI,thereby improving neuronal degeneration,inflammatory cell infiltration,and ***:Trigonelline shows neuroprotective properties in SCI rats by reducing allodynia,hyperalgesia,and inflammation,stabilizing mitochondrial enzyme complexes,and modulating apoptotic and neurotrophic ***,trigonelline holds promise as a potential neuroprotective agent.

关键词： Bax Bcl-2 BDNF COX-Ⅱ Spinal cord injury Trigonelline

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