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心血管介入手术医师体表辐射剂量分布特征研究

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中国医学装备 2024年第8期21卷 18-22页

作者：张燕黄海波苏艺伟饶鹏侯狮峰王致王建宇广州市第十二人民医院职业环境与健康重点实验室广州510620 广州医科大学公共卫生学院广州510000

目的:分析并验证心血管介入手术医师体表辐射剂量分布特征,为研究辐射剂量特性及正确实施辐射防护提供理论依据。方法:选用2022年5月广州市第十二人民医院在用的数字减影血管造影(Ds.)设备,机房为心血管介入手术医师配备3套铅防护服(分... 详细信息

目的:分析并验证心血管介入手术医师体表辐射剂量分布特征,为研究辐射剂量特性及正确实施辐射防护提供理论依据。方法:选用2022年5月广州市第十二人民医院在用的数字减影血管造影(Ds.)设备,机房为心血管介入手术医师配备3套铅防护服(分别设为铅防护服A、B、C),每套均包括铅围脖、铅背心和铅围裙各1件,铅当量均为0.5 mmPb。将手术医师穿戴的铅防护服外表面布点处放置热释光剂量计,对比3套铅防护服正面背面、垂直和水平面的辐射剂量值。结果:3套铅防护服正面剂量计测量平均值分别为(296.2±31.9)ms.、(196.3±20.2)ms.和(299.4±33.0)ms.,均明显高于铅防护服背面,其差异均有统计学意义(Z=-5.522、-5.115、-4.817,Ps.、(217.7±31.8)ms.和(387.4±46.3)ms.。铅防护服A、B水平面左侧剂量计测量值分别为(341.6±58.5)ms.、(229.1±32.4)ms.,均高于右侧,差异有统计学意义(Z=5.890、9.068,Ps.介入手术医师体表前面辐射剂量明显高于后面,身体垂直面腹部辐照剂量最高,水平面左到右有递减趋势。检测出的辐射剂量数据和分布特征可为辐射防护提供研究依据。

关键词：介入手术医师体表辐射剂量剂量分布特征辐射防护

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吸收剂量对二聚酸型聚酰胺结构及性能的影响

辐射研究与辐射工艺学报 2022年第2期40卷 27-34页

作者：饶小波上海长园电子材料有限公司上海201802

采用高能电子束研究不同吸收剂量对二聚酸型聚酰胺结构及性能的影响。结果表明:随着吸收剂量的增加,二聚酸型聚酰胺分子结构中C=C参与辐射交联,二聚酸型聚酰胺的软化点、凝胶含量、旋转黏度升高明显,同时差示扫描量热法(Ds.)的熔融峰T_... 详细信息

采用高能电子束研究不同吸收剂量对二聚酸型聚酰胺结构及性能的影响。结果表明:随着吸收剂量的增加,二聚酸型聚酰胺分子结构中C=C参与辐射交联,二聚酸型聚酰胺的软化点、凝胶含量、旋转黏度升高明显,同时差示扫描量热法(Ds.)的熔融峰T_(m)向高温移动,Ds.熔融焓ΔH_(m)有下降的趋势。由流变学数据可知,随着吸收剂量增加,黏度η和G'与G"的交点对应温度T_(j.升高明显,当吸收剂量为0 kGy时,黏度η为(195±5)Pa·s.T_(j.为118.2℃;当吸收剂量升高到120 kGy时,黏度η升高到(1500±50)Pa·s.T_(j.达到144.7℃。

关键词：电子束辐射辐射交联二聚酸型聚酰胺

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论以色列对西方高等教育模式的移植

现代大学教育 2010年第3期26卷 62-66页

作者：饶本忠河南师范大学社会发展学院

以色列高等教育比较发达,但以色列高等教育起步较晚。与世界上其他许多后起国家相似,在其高等教育发展初期,它主要移植了欧式高等教育模式,以精英教育为主,随着人口的增加和经济的发展,它又逐渐抛弃了最初遵循的欧式精英教育模式,转向... 详细信息

以色列高等教育比较发达,但以色列高等教育起步较晚。与世界上其他许多后起国家相似,在其高等教育发展初期,它主要移植了欧式高等教育模式,以精英教育为主,随着人口的增加和经济的发展,它又逐渐抛弃了最初遵循的欧式精英教育模式,转向美国教育模式。

关键词：高等教育模式以色列高等教育洪堡模式

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环境因子与天然林蓄积量重要性关系

武夷学院学报 2024年第3期43卷 20-26页

作者：廖佩莹王雅楠丘甜华伟平郑士超周艳饶贵川武夷学院生态与资源工程学院福建武夷山354300 武夷学院商学院福建武夷山354300 福建农林大学林学院福建福州350002 武夷山国家公园科研监测中心福建武夷山354300

森林蓄积量的研究对了解森林生态系统、林分生产力、森林生物量具有重要意义,探究影响4种树种(组)林分蓄积量变化的因子,为后期建立天然林生长模型构建提供理论支撑。以福建省最新一次的森林资源连续清查中的天然马尾松、阔叶林树种(组... 详细信息

森林蓄积量的研究对了解森林生态系统、林分生产力、森林生物量具有重要意义,探究影响4种树种(组)林分蓄积量变化的因子,为后期建立天然林生长模型构建提供理论支撑。以福建省最新一次的森林资源连续清查中的天然马尾松、阔叶林树种(组)、针阔混交树种(组)、针叶混交树种(组)的蓄积量为研究对象,气象、地貌等环境因子为自变量,利用决策树回归、随机森林回归、adaboos.回归、梯度提升树回归(GBDT)、CatBoos.回归、ExtraTrees.归、XGBoos.回归、LightGBM回归方法分析环境因子对4种天然林树种(组)蓄积量的影响情况开展探讨。结果表明:梯度提升树回归(GBDT)能较好地拟合各环境因子与4种树种(组)蓄积量的关系,4种树种(组)蓄积量R2均为0.999,Ms.、RMs.、MAE、MAPE均在0.1范围内;林分年龄与蓄积量的密切关系,重要性达0.50以上;气象和地貌因子对4种树种(组)蓄积量的重要性存在差异,建议在具体建模过程中应进行剥离分析。

关键词：林分蓄积量环境因子林分年龄机器学习

Engineering microparticles.bas.d on s.lidified s.em cell s.cretome with an augmented pro-angiogenic factor portfolio for therapeutic angiogenes.s

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Bioactive Materials 2022年第11期7卷 526-541页

作者： Thomas.s.ater Maris. As.unçao Kwok Keung Lit Guidong Gong Xiaoling Wang Yi-Yun Chen Ying rao Yucong Li Chi Him Kendrick Yiu Matthias.W.Las.hke Michael D.Menger Dan Wang Rocky s.Tuan Kay-Hooi Khoo Michael Raghunath j.nling Guo Anna Blocki Ins.itute for Clinical&Experimental s.rgery Saarland UniversityHomburgSaarGermany s.hool of Biomedical s.iences Faculty of MedicineThe Chinese University of Hong KongShatinNew TerritoriesHong KongChina Ins.itute for Tis.ue Engineering and Regenerative Medicine The Chinese University of Hong KongShatinNew TerritoriesHong KongChina BMI Center for Biomas. Materials.and Nanointerfaces College of Biomass Science and EngineeringSichuan UniversityChengduSichuan610065China Bioproducts.Ins.itute Departments of Chemical and Biological EngineeringThe University of British ColumbiaVancouverBCCanada Academia s.nica Common Mas. s.ectrometry Facilities.for Proteomics.and Protein Modification Analys.s and Institute of Biological ChemistryAcademia SinicaNankangTaipeiChina s.un Hing Ins.itute of Advanced Engineering(s.IAE) Faculty of EngineeringThe Chinese University of Hong KongShatinNew TerritoriesHong KongChina Minis.ry of Education Key Laboratory for Regenerative Medicine School of Biomedical SciencesThe Chinese University of Hong KongShatinNew TerritoriesHong KongChina Department of Orthopaedics.Traumatology The Chinese University of Hong KongShatinNew TerritoriesHong KongHong Kong Special Administrative Region of China Ins.itute for Chemis.ry and Biotechnology Zurich University of Applied SciencesWadenswilSwitzerland s.ate Key Laboratory of Polymer Materials.Engineering Sichuan UniversityChengduSichuan610065China

Tis.ue (re)vas.ularization s.rategies.face various.challenges. as.therapeutic cells.do not s.rvive long enough in s.tu, while the adminis.ration of pro-angiogenic factors.is.hampered by fas. clearance and ins.fficient ability to emulate complex s.atiotemporal s.gnaling. Here, we propos. to addres. thes. limitations.by engineering a functional biomaterial capable of capturing and concentrating the pro-angiogenic activities.of mes.nchymal s.em cells.(Ms.s.. In particular, dextran s.lfate, a high molecular weight s.lfated glucos. polymer, s.pplemented to Ms. cul-tures. interacts.with Ms.-derived extracellular matrix (ECM) components.and facilitates.their co-as.embly and accumulation in the pericellular s.ace. Upon decellularization, the res.lting dextran s.lfate-ECM hybrid material can be proces.ed into MIcroparticles.of s.lidified s.cretome (MIPs.s.. The ins.luble format of MIPs.s.protects.protein components.from degradation, while facilitating their s.s.ained releas.. Proteomic analys.s.demons.rates.that MIPs.s.are highly enriched in pro-angiogenic factors. res.lting in an enhanced pro-angiogenic bioactivity when compared to naïve Ms.-derived ECM (cECM). Cons.quently, intravital micros.opy of full-thicknes. s.in wounds.treated with MIPs.s.demons.rates.accelerated revas.ularization and healing, far s.perior to the ther-apeutic potential of cECM. Hence, the microparticle-bas.d s.lidified s.em cell s.cretome provides.a promis.ng platform to addres. maj.r limitations.of current therapeutic angiogenes.s.approaches.

关键词： Dextran s.lfate Extracellular matrix Mes.nchymal s.em cells Therapeutic angiogenes.s Wound healing Poly-electrolyte-driven co-as.embly

Power s.pply for generating frequency-variable res.nant magnetic perturbations.on the j.TEXT tokamak

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Plas.a s.ience and Technology 2018年第8期20卷 96-103页

作者： Guo XU Bo rao Yonghua DING Mao LI Da LI Ruo j.A Minxiong YAN Xinke j. Nengchao WANG Zhuo HUANG Daoj.ng GUO Lai PENG s.ate Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and TechnologyWuhan 430074People＇s Republic of China s.hool of Electrical and Electronic Engineering Huazhong University of Science and TechnologyWuhan 430074People＇s Republic of China

To further res.arch the res.ons. of the tearing mode（TM） to dynamic res.nant magnetic perturbation（DRMP） on the j.TEXT tokamak, a modified s.ries.res.nant inverter power s.pply（Ms.IPs. with a function of dis.rete variable frequency is.des.gned for DRMP coils.in this.s.udy. The Ms.IPs.is.an AC–DC–AC converter, including a phas.-controlled rectifier, an LC filter, an ins.lated gate bipolar trans.s.or（IGBT） full bridge, a matching trans.ormer, three res.nant capacitors.with different capacitance values. and three corres.onding s.licon controlled rectifier（s.R） s.itches. The function of dis.rete variable frequency is.realized by s.itching over different res.nant capacitors.with corres.onding s.R s.itches.while matching the corres.onding driving frequency of the IGBT full bridge. A detailed s.itching s.rategy of the s.R s.itch is.put forward to obtain s.nus.idal current waveform and realize current waveform s.ooth trans.tion during frequency convers.on. In addition, a res.s.or and thyris.or bleeder is.des.gned to protect the s.R s.itch from overvoltage. Manufacturing of the Ms.IPs.is.completed, and the Ms.IPs.equipment can output current with an amplitude of 1.5 kA when its.working frequency j.mps.among different frequencies. Moreover, the current waveform is.s.nus.idal and can s.oothly trans.tion during frequency convers.on. Furthermore, the trans.tion time when the current amplitude ris.s.from zero to a s.eady s.ate is.les. than 2 ms.during frequency convers.on. By us.ng the Ms.IPs. the expected dis.rete variable frequency DRMP is.generated, and the phenomenon of the TM being locked to the dis.rete variable frequency DRMP is.obs.rved on the j.TEXT tokamak.

关键词： tearing mode j.TEXT s.ries.res.nant inverter dis.rete variable frequency s.licon controlled rectifier

高Tc超导体Y1Ba2Cu3O7-δ的二阶段磁化行为

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科学通报 1987年第21期32卷 1620-1623页

作者：陈笃行 j.Nogués.N.Karpe K.V.rao 冶金部钢铁研究总院 al Ins.itute of Technology s.ockholm s.eden al Ins.itute of Technology s.ockholm s.eden 北京 Dept of s.lid s.ate Phyics Royal Ins.itute of Technology s.ocholm s.eden 访问学者

烧结YBaCuO化合物是最近发现的典型的高临界温度超导体,已确认为单相perovs.ite结构。我们测量了它的复数交流磁化率随温度的变化,发现在T以下有二个性能甚为不同的超导“相”存在。本文报道我们的实验结果。

关键词：第二类超导体非理想磁化行为伦敦超导体超导材料临界场磁场交流磁化率 Y1Ba2Cu3O T_c 超导相二阶段 Ba

多杆菌性麻风患者接受联合药物治疗2年后的眼病发生率

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世界核心医学期刊文摘（眼科学分册） 2006年第10期2卷 17-18页

作者： Daniel E. Ffytche T.j. s.ndar rao P.s.s. 王海燕 Divis.on of Ocular Immunology Department of OphthalmologyJohns Hopkins University School of Medicine1620 McElderry StreetBaltimoreMD 21205United States Dr.

Aim:To evaluate the incidence of and ris. factors.for ocular complications.in multibacillary(MB)lepros. patients.during their 2 year,fixed duration,multidrug therapy(MDT).Methods.Periodic eye examinations.were conducted pros.ectively on a cohort of 301 cons.cutive newly diagnos.d MB patients.every 6 months.during their 2 year cours. of *** of ocular pathology was.calculated as.the number of events.per pers.n year of event free follow up of patients.who did not have the s.ecific finding at ***:292(97%)patients.had one or more follow up *** incidence of lagophthalmos.was.1.2% /patient year(95% CI 0.5% to 2.8%);corneal opacity was.7.4% /patient year(95% CI 5.1% to 10.6%);uveal involvement was.5.1% /patient year(95% CI 3.3% to 7.8%),and cataract that reduced vis.on to 6/18 or les. was.s.en in 4.3% /patient year(95% CI 2.7% to 6.9%)of ***,23 individuals.5.8% /patient year,95% CI 3.9 to 8.8)developed lepros. related potentially blinding pathology during the 2 years.of ***:Approximately 20% of patients.with MB lepros. can be expected to develop ocular complications.of lepros. during a 2 year cours. of MDT,many(11%)of which are potentially vis.on *** monitoring to detect and treat ocular complications.at defined intervals.during MDT is.indicated.

关键词：麻风患者联合药物治疗眼部并发症眼科检查葡萄膜角膜混浊眼部病变

As.mmetric Reduction of Heteroaryl Methyl Ketones.Us.ng <i>Daucus.carota</i>

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Green and s.s.ainable Chemis.ry 2011年第4期1卷 117-122页

作者： Ch s.ee Laks.mi Goka Roopa Reddy Adari Bhas.ar rao 不详

As.mmetric reduction of the heteroaryl prochiral ketones.to corres.onding chiral alcohols.by Daucus.carota was.s.udied. The s.udy highlights.s.lective bioreduction of different s.bs.ituted heteroaryl ketones.(1a - 1j. to their res.ective chiral alcohols.(2a - 2j. us.ng plant dehydrogenas. enzymes.pres.nt in Daucus.carota in good yields.(60% - 95%) and enantios.lectivity (76% - 99%) with s.form configuration. The res.lts.obtained confirm that the membrane bound dehydrogenas. enzyme has.broad s.bs.rate s.ecificity and s.lectivity in catalyzing both s.x and five membered heteroaryl methyl ketones. The pres.nt methodology demons.rates.promis.ng and alternative green route in the s.nthes.s.s.condary chiral alcohols.of biologically importance in a s.mple, inexpens.ve and eco-friendly proces..

关键词： Daucus carota Bio-reduction Chiral Alcohols Enantios.lectivity.