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The spread and outbreak of computer viruses in the information age have had a huge impact on social production and people's lives, and it is particularly important to effectively prevent and suppress the spread of computer viruses. In this paper, a computer virus propagation model with immune function is established making use of the optimal control method. It obtains the basic reproduction number R0 based on the method of the next generation matrix; It builds the Liapunov function, and proves the condition of the global stability of the disease-free equilibrium point when R0≤1; The optimal solution is obtained based on Pontryagin's principle of maximum value. Numerical simulation results show that the optimal control model can detect and deal with infected computers while improving the installation and protection rate of antivirus software, and the control target time is the shortest and the control cost is the lowest.(信息时代计算机病毒的传播、爆发对社会生产和人民生活造成严重影响，有效预防和抑制计算机病毒传播尤为重要。结合最优控制方法，建立了一种具有免疫效力的计算机病毒传播模型。由下一代矩阵方法求得基本再生数R0，并证明了无病平衡点的全局稳定性，通过敏感性分析找到对R0敏感的参数；构建了Liapunov函数，证明了当R0≤1时无病平衡点的全局稳定性；基于庞特里亚金最值原理得到最优解。用数值模拟方法对不同控制措施下的结果进行对比分析，结果表明，在及时检测并隔离被感染计算机并提高杀毒软件的安装率和保护率的情况下，控制目标的时间最短且控制成本最低。)

目的探讨双胎妊娠并发子痫前期的发病趋势、特征及危险因素。方法回顾性分析2011年1月至2019年12月在中山大学附属第一医院住院分娩的1 542例双胎妊娠孕妇子痫前期的发病趋势。最终1 384例双胎妊娠孕妇纳入后续发病特征及危险因素分析，根据绒毛膜性将其分为单绒毛膜性（monochorionic，MC）组和双绒毛模性（dichorionic， DC）组，MC共有403例，其中子痫前期（preeclampsia， PE）组55例，非PE组348例；DC共有981例，其中PE组105例，非PE组876例；分别比较不同绒毛膜性孕妇PE组和非PE组的基本资料和分娩结局，采用单因素分析和多因素Logistic回归分析不同绒毛膜性双胎妊娠发生子痫前期的危险因素。结果双胎妊娠PE的总发病率为10.4%，2011-2019年各年PE的发病率在7.8%～11.8%之间波动。无论MC与DC双胎妊娠，PE组孕妇贫血（MC为58.2%和39.7%，P=0.010；DC为59%和38%，P=0.000）、低蛋白血症（MC为7.3%和1.7%，P=0.035；DC为10.5%和0.7%，P=0.000）、早产（MC为94.5%和70.1%，P=0.000；DC为89.5%和54.8%，P=0.000）、产后出血（MC为21.8%和10.6%，P=0.018；DC为20.9%和13.4%，P=0.035）、新生儿转新生儿重症监护室（MC为49.1% 和28.6%，P=0.000；DC为26.7%和15.6%，P=0.000）的发生率均较非PE组高，组间差异有统计学意义；DC双胎妊娠PE组小胎出生体质量和大胎出生体质量均较非PE组轻，组间差异有统计学意义（P=0.000；P=0.017）。孕期增重过多、辅助生殖技术受孕是MC双胎PE的独立危险因素；孕前BMI≥24 kg/m2、孕期增重过多、双胎体质量差过大是DC双胎妊娠PE的独立危险因素。结论双胎妊娠PE的发病率波动于7.8%～11.8%；不同绒毛膜性双胎妊娠PE的危险因素和分娩结局略有差异；孕期增重过多、辅助生殖技术受孕、孕前BMI≥24 kg/m2、双胎体质量差过大是双胎妊娠PE的危险因素，提示孕期体质量管理尤为重要。

【目的】探讨家庭亲密与师生依赖对学龄前儿童进入幼儿园1年后的多动行为的影响。【方法】以2014年深 圳市龙华区7 465名新入园的学龄前儿童为研究对象，由其主要照护人填写家庭环境量表中文版（FES-CV）和Conners父母 用症状问卷（PSQ），评价其入园前的家庭亲密状况及入园时多动行为。1年后进行随访，再次由主要照护人使用PSQ评价 儿童的多动行为，由主班教师填写师生关系量表（STRS）评价其入园第一年的师生依赖水平。校正家庭社会经济状况及学 龄前儿童基线时的多动指数后，应用logistic回归分析家庭亲密、师生依赖与多动行为关联的主效应及交互作用。【结果】 学龄前儿童入园1年后多动行为的发生与家庭亲密呈负关联（OR=0.85，95% CI=0.75~0.97，P=0.01），与师生依赖的关联无统 计学意义（OR=1.00，95% CI=0.93~1.08，P=0.98），进一步分析提示家庭亲密和师生依赖与学龄前儿童入园1年后的多动行为 的关联存在交互作用（OR=0.96，95% CI=0.92~0.99，P=0.03）。家庭亲密（OR=1.08，95%CI=0.88~1.34，P=0.47）、师生依赖 （OR=1.03，95%CI=0.93~1.15，P=0.53）对学龄前儿童入园1年后多动行为的改善的影响没有统计学意义。【结论】家庭亲密 和师生依赖与学龄前儿童入园1年后新发多动行为的关系存在效应修饰作用。

为解决经典AODV（按需距离矢量）路由协议中目的节点在已建立路由链路信号覆盖范围内随机移动时脱离其原来直接通信节点而断路、通信恢复时间长以及网络负载大等问题,对利用AODV协议Hello消息报文激活中间节点与目的节点的通信切换实现快速路由修复进行了研究,并得到改进后的路由协议AODVL。仿真结果表明,AODVL比经典的AODV路由协议减小了网络负载并缩短了路由修复时间。AODVL更适用于目的节点在已建立路由链路信号覆盖范围内随机移动的网络,节点间通信具有更高的实时性。

本文报道一种适合用现有工艺条件进行研制的OEIC光发送机的驱动电路。该驱动电路不仅对信号具有一定的整形能力,而且更适于高速脉码调制。同时,当制作工艺条件变化时具有较高的稳定性。对该电路进行计算机辅助分析和优化,得到该电路的上升、下降时间为120ps、140ps。

[目的]探讨前列腺特异膜抗原单克隆抗体7E11C5.3介导铼-188和平阳霉素（PYM）导向治疗前列腺癌细胞系LNCaP的体外作用。[方法]以葡聚糖为中介体制备7E11C5.3-PYM偶联物，间接ELISA法测定免疫活性，2,3,5-氯化三苯基四氮唑（TTC）法测定抑菌活性。采用2-巯基乙醇直接还原法制备188Re-7E11C5.3标记物，纸层析法测定标记率和放化纯度，直线回归外推法测定免疫活性分数。四唑盐（MTT）法测定体外细胞毒作用。[结果]7E11C5.3-PYM偶联物中7E11C5.3和PYM的克分子比为1∶54，偶联后单抗的免疫活性降低了10%～20%，偶联物中PYM的抑菌活性为游离PYM的25%。188Re-7E11C5.3的标记率为93.16%±2.18%，放化纯度为95.62%±0.48%，免疫活性分数为74.86%±1.86%。7E11C5.3-PYM和188Re-7E11C5.3对LNCaP细胞的抑制作用分别强于游离PYM和188ReO4-；两者单独用药时，其半数抑制浓度（IC50）分别为（10.17±2.06）µg/mL和（23.38±3.73）×104 Bq/mL；两者联合用药时，其IC50值分别为（1.83±0.20）µg/mL和（6.82±0.73）×104 Bq/mL。[结论] 7E11C5.3-PYM和188Re-7E11C5.3联合用药对前列腺癌细胞的抑制作用显著强于单独用药。

【目的】对珠海市部分中青年警察血脂水平进行调查分类，为特殊职业人群血脂异常防治提供信息。【方法】2140例健康体检的中青年警察按年龄性别分组，测定血清甘油三醑、总胆固醇、低密度脂蛋白胆固醇和高密度脂蛋白胆固醇水平。根据我国“血脂异常防治建议”标准进行分类，并对血脂异常进行临床分型。查阅相关文献，将警察血脂特点与同期发表的文献资料进行对比分析。【结果】2140名中青年警察中，总胆固醇、甘油三醑和低密度脂蛋白胆固醇平均水平均随年龄的增大而上升．3项指标男性高于同年龄段女性。中年女性警察的平均血脂水平与本地区城市中年女性血脂水平基本一致，与本地区城市中年男性人群比较，中年男性警察总胆固醇平均水平[（5．65±0．98）mmol／L vs（5．04±1．65）mmol／L,P〈0．001]、甘油三酯平均水平[（2．09±1．65）mmol／L、vs（1．41±1．06）mmol／L，P〈0．001]明显升高。【结论】珠海市中青年警察的血脂异常呈年轻化趋势．中年男性警察血脂异常的严重程度高于本地相应男性普通城市居民。

[目的]探讨家长参与程度对初中生吸烟行为的作用。[方法]在广州黄埔区整群随机抽取6所中学。使用自填式问卷对初中学生和家长（2851套）进行横断面调查，以家长态度与行为共4个条目的量化总分将家长参与程度分成5个等级，再评价家长参与程度对初中生吸烟相关知-信-行的影响。[结果]2617套有效问卷中。家长参与程度Ⅰ-Ⅴ级的构成比分别为1．9％、4．9％、13．4％、33．4％和46．4％。学生感受到的家长吸烟许可率，Ⅰ级为5．9％，Ⅱ级为1．6％，Ⅲ级为1．1％，Ⅳ级为0．6％，Ⅴ级为0．7％。各组学生的吸烟与健康知识水平无统计学意义的差别（P〉0．05）。学生吸烟相关的正、负性态度得分和态度总分都随着家长参与程度的增加而升高。家长参与程度Ⅰ～Ⅴ级的初中生不规律吸烟率分别为21．6％、16．5％、15．4％、13．5％和14．1％，规律吸烟率分别为11．8％、8．7％、4．3％、3．9％和3．5％，其发生率的差异有统计学意义（P〈0．05），而且家长参与程度与学生吸烟行为存在统计学意义的负相关（Spearman，r=-0．042，P=0．031）。[结论]家长参与能够对初中生吸烟相关的态度和行为产生直接或间接影响，应在青少年控烟中得到更多的重视。

【目的】为了解广东省35 ～ 44 岁居民吸烟情况。【方法】1996 年10 ～ 12 月和1997 年3～ 5 月采用多阶段整群随 机抽样方法选择样本, 共调查35 ～ 44 岁居民1 554 人。【结果】35 ～ 44 岁居民男、女吸烟率分别为81.4%和4.1%。城市居 民786 人、乡村768 人, 男性吸烟率分别为78.1%和84.8 %, 接近全国最高水平。【结论】建议把35 ～ 44 岁年龄段居民作为控 烟的重点人群, 为今后在广东省有组织、有计划、有针对性地进行控烟运动提供依据。

【目的】评价99mTc-MIBI 与201T1 肺肿瘤显像在原发性肺癌诊断中临床意义。【方法】28 例肺癌患者进行了201T1 早 期( 15 min)与延迟( 3 h)肺肿瘤平面显像,其中 23 例有同期的99mTc-MIBI 显像资料; 勾画各时相前位图像上病变部位( T)及对侧 正常肺组织(N)的感兴趣区, 计算摄取比值( T/N)及滞留指数[ RI=(延迟 T/N-早期 T/N)×100/早期 T/N) ] , 并取病灶部位放 射性较正常肺组织摄取明显增高为阳性指标进行定性分析。【结果】99m Tc-MIBI 早期与延迟显像肉眼定性分析诊断肺癌的阳 性率分别为 86. 96%和 78. 26%,201T1 显像两者阳性率均为 89. 29%; 99mTc-MIBI 早期与延迟显像 T/N 分别为 1. 26±0. 19 与 1. 24 ±0. 19,201T1 为 1. 43±0. 21和 1. 59±0. 32,99mTc-MIBI 与201T1 比较早期 T/N 之间与延迟 T/N 之间均有明显差异(t 值分别为 5. 538与 7. 33, P 值均

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BACKGROUND: The development and utilization of shale gas has become an important way to ensure national energy security and achieve global carbon neutrality goals. Shale gas reservoir is the direct target layer of shale gas exploration and development, because its shale nanopore throat system, dominated by organic pores, has the characteristics of integrated source storage, low porosity, low permeability and non-darcy flow. The evaluation of shale reservoir evaluation needs to break through the bondage of traditional inorganic pore evaluation ideas and the bottleneck of nanoscale characterization technology, and adopt higher precision and resolution experimental technology to characterize nanopores and depict organic pores. OBJECTIVES: To understand the research progress on characterization technology of nano organic pore structure in shale and explore the evolution mechanism of organic pore formation, its experimental technical bottlenecks and possible solutions. METHODS: According to the experimental types and principles, shale nanopore analysis can be divided into two types: physical experiment technology and imaging analysis technology. The former mainly carries out quantitative physical experiment analysis of rock physical properties, while the latter carries out microscopic in-situ observation and image analysis of pore structure. RESULTS: Since organic pores were first discovered in the Barnett shale in North America in 2009, significant progress has been made in studying shale characterization techniques and developmental features. (1)Multi-scale and multi-type nanopore characterization techniques were established. Among them, the quantitative microstructure characterization technologies are dominated by mercury-adsorption joint measurement method and pulse attenuation method. Quantitative parameters of shale physical properties and full aperture distribution ranging from 0. 35nm to 10000nm and permeability of <1μD can be accurately obtained. High-resolution microscopy scanning based on field-emission SEM and microscopy-CT forms a multi-scale structure reconstruction technology of nanopore, and thus 2D-3D image information is available. (2) The formation and evolution of organic pores are controlled by organic matter type, rock evolution and other factors. It is necessary to reveal the internal connection between the influencing factors and the physical evolution law of organic matter molecular structure, which is the key to identify the heterogeneity of shale reservoirs. Formation and keeping of organic pores is in the process of decomposition and condensation reaction competition space effect. (3) Previous studies established a series of kerogen and asphalt structure model for the molecular organic pores evolution mechanism, providing the theoretical basis for research on the genetic mechanism and evolution law of organic pores at the molecular level. Transmission electron microscope and atomic force microscope are used to observe molecular space arrangement and microstructure internal form in stereo. These techniques enable the understanding of the mechanisms of organic pore formation and preservation at the nanoscale. CONCLUSIONS: In - situ structure imaging and component scanning technology, reservoir description, composition analysis and digital core integration, are developed to the structure and composition, pore permeability and brittle integration dynamic evaluation. A leap from microstructural analysis to macroscopic big data prediction is realized, meeting the needs of efficient exploration and development of shale gas geology and engineering integration. [ABSTRACT FROM AUTHOR]

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Copyright of National Palace Museum Research Quarterly is the property of National Palace Museum and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

旨在为大豆低温粕产品质量的提高及生产成本的降低提供指导，对当前两种典型的大豆粕低温脱溶工艺（气流闪蒸脱溶和AB双筒脱溶）分别进行了详细介绍，从低温粕水溶性蛋白的损失、碎料的形成、粕料色泽、设备的正常运行及维护周期、溶剂消耗和蒸汽消耗等方面对两种大豆粕低温脱溶工艺进行对比分析。相较于气流闪蒸脱溶工艺，AB双筒脱溶过程中水溶性蛋白的损失更低、粕料成型度更好、粕料色泽变化更小，有效地减轻了设备堵塞、磨损现象，延长了设备使用周期，减少了系统维护、检修费用，同时也间接地节省了溶剂和蒸汽消耗。综上，可优先选择AB双筒脱溶工艺对大豆粕进行低温脱溶处理。To provide guidance for improving the quality of soybean white flake and reduce production cost, the current typical two soybean meals low temperature desolventizing processes, namely air flow flash desolventizing and tank AB double-cylinder desolventizing process were introduced in detail, and the two soybean meals low temperature desolventizing processes were compared from the loss of water-soluble protein in soybean white flake, the formation of crushed material, the color of meal, the normal operation of the equipment and the maintenance cycle, the solvent consumption and steam consumption, etc. Compared with air flow flash desolventizing process, tank AB double-cylinder desolventizing process has lower water-soluble protein loss, better meal forming, smaller meal material color change, and can effectively reduce the equipment blockage, wear phenomenon, extend the equipment usage cycle, reduce the system maintenance, examine and repair costs, indirectly save the solvent and steam consumption. In conclusion, the tank AB double-cylinder desolventizing process can be preferred for the low temperature desolventizing treatment of soybean meals.

在玉米胚芽预榨饼浸出制油过程中，湿粕脱溶是一个很重要的工序。基于玉米胚芽预榨饼的特点，对其浸出过程中湿粕脱溶工艺和设备进行了改进，并应用于生产实践。采用浸出器强制沥干和新型的高料层蒸脱机的技术方案，在强制沥干真空度1 500 Pa、蒸脱机脱溶层净高3 600 mm、脱溶时间35~40 min条件下，粕残溶达到650 mg/kg及以下，闪爆实验合格。通过采用新工艺和新技术，能在保证玉米胚芽粕产品品质的同时达到节能降耗的目的。In the process of oil extraction from corn germ pre-pressed cake, wet meal desolventizing is a very important process. Based on the characteristics of corn germ pre-pressed cake, the process and equipment of wet meal desolventizing were improved, and it was applied in production practice. Using forced drainage in extractor a new type of high material layer DTDC, under the conditions of forced drainage vacuum 1 500 Pa, net height of DTDC′s desolventizing layer 3 600 mm, and desolventizing time 35-40 min, the residual solvent in meal was 650 mg/kg and below, and the flash explosion test was qualified. Through the adoption of new processe and new technology, the quality of the meal can be guaranteed at the same time to achieve the purpose of energy saving and consumption reduction.

索-桁结构是一种有潜力的空间结构,但目前的研究尚不够深入.本文提出了一种圆形平面索-桁预应力结构,采用反应谱法和时程法分析,研究了其动力性能.结果表明,该种结构的频谱极为密集,振型较为复杂;这类结构采用反应谱法计算动内力将导致不可接受的误差,而应采用相应的时程分析法计算动内力.同时还得出了这种结构预应力的施加不可缺少,否则将有可能导致动力破坏的结论.