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食肉目（Carnivora）动物对维持食物网稳定和生态系统功能平衡具有重要作用，理解捕食者与其猎物的时间生态位有助于珍稀物种的保护。为探究豹猫（Prionailurus bengalensis）与同域分布潜在猎物的日活动特征、季节性变化和种间活动重叠规律，于2018年9月—2020年8月在甘肃兴隆山国家级自然保护区布设60台红外相机开展持续监测，累计工作日33 521 d，共捕获豹猫370次、灰尾兔（Lepus oiostolus） 390次、鼠类（Rats）760次和环颈雉（Phasianus colchicus）834次独立有效事件。基于核密度曲线和活动重叠度分析豹猫、灰尾兔、鼠类和环颈雉的日活动节律，揭示捕食者与猎物在青草期和枯草期的日活动节律变化模式。结果显示：（1）豹猫和鼠类的日活动节律为双峰型夜行性，环颈雉为持续峰型昼行性，而灰尾兔表现为峦峰型泛夜行性。（2）除环颈雉外，其他3个物种日活动节律季节性变化明显，枯草期均倾向于凌晨活动，且豹猫也增加了白天午后的活动时长，具有较强的适应性。（3）豹猫与鼠类、灰尾兔的重叠度较高，但存在季节差异，青草期与鼠类重叠度最高（∆4=0.779），枯草期与灰尾兔重叠度最高（∆1=0.720），与环颈雉青草期（∆4=0.356）和枯草期（∆1=0.453）重叠度均最低。本研究从时间维度评估了豹猫与其猎物的活动行为响应，为探讨兴隆山豹猫与猎物的时空共存机制和为自然保护地开展关键物种保护与有害物种防治提供科学依据。

随着新型电力系统建设的不断推进，电力终端和采集类设备的大范围接入，对变电站的巡检工作开展产生了巨大的挑战，实施难度大、定位精度无法保障。为此，设计了一种基于5G的大规模MIMO的融合定位算法，首先，利用静止波束成形方法拟合粗定位体系结构，确定直接定位方法的搜索区域。然后，推导四阶累积量拟合近场模型，并计算与远场基站关联的自适应权值。最后，构建了一种基于远场与近场联合直接定位的位置感知模型，将直接定位方法有效应用于粗定位区域，解决了依靠传统到达角定位方式密集小区误差大的问题。仿真结果表明，在相同的实验环境下基于5G基站的远近场景大规模MIMO融合定位技术具有更高的定位精度和稳定性，能够有效保证站内巡检定位的准确性。

为研究粗骨料类型、空心率、长细比和偏心距对方中空夹层钢管陶瓷再生混凝土柱偏压力学性能的影响，进行了16根试件的偏压试验，其中粗骨料类型分别为废弃陶瓷和天然碎石。试验结果表明：所有试件均表现为弹塑性失稳破坏；试件的极限承载力和抗弯刚度随长细比和偏心距的增大而降低，其中中空夹层试件的极限承载力高于实心试件的相应值；陶瓷再生混凝土试件展现出了较好的延性和变形能力，其极限承载力与普通混凝土试件接近。使用有限元软件对试验进行模拟，模拟得到的荷载-跨中挠度曲线整体与试验曲线接近。采用T/CCES 7—2020和DB 36/J001—2007分别对中空夹层试件和实心试件极限承载力进行计算，计算结果接近试验值。

旨在为葵花籽仁的分级应用提供理论依据，以葵花籽为原料，通过多级精分设备将葵花籽进行脱壳、分级，分为小（≤3 mm）、中（3~4 mm）、大（＞4 mm）3种粒径等级的葵花籽仁，分别对葵花籽仁组成进行比较分析。结果表明，各粒径葵花籽仁含油量均超过60%，油中不饱和脂肪酸相对含量超过85%，且小粒径葵花籽仁含油量及油中亚油酸相对含量最高。各粒径葵花籽仁粗蛋白质含量为44.93%~53.33%，大粒径葵花籽仁粗蛋白质及氨基酸含量最高。3种粒径葵花籽仁绿原酸总量为26 314.93 ~28 095.98 ng/mg，中粒径葵花籽仁总绿原酸总量最高。3种粒径葵花籽仁总淀粉含量为0.067%~0.090%，小粒径葵花籽仁总淀粉含量最高；3种粒径葵花籽仁抗性淀粉含量为0.019%~0.032%，中粒径葵花籽仁抗性淀粉含量最高。 In order to provide a theoretical basis for the application of sunflower seed kernels grading, sunflower seed were used as raw material, and sunflower seeds were hulled and graded by multi-stage fine separation system to three particle sizes of small (≤3 mm), medium (3-4 mm) and large (>4 mm), and the composition of sunflower seed kernels was compared and analyzed, respectively.The results showed that the oil content of sunflower seed kernels of all particle sizes was more than 60%, the relative content of unsaturated fatty acids in oil was more than 85%, and the sunflower seed kernels with small particle size had the highest oil content and relative content of linoleic acid in oil. The content of crude protein of sunflower seed kernels was 44.93%-53.33%, and the sunflower seed kernels with large particle size had the highest crude protein and amino acids content. The content of chlorogenic acid of sunflower seed kernels was 26 314.93 -28 095.98 ng/mg, and the sunflower seed kernels with medium particle size had the highest chlorogenic acid content. The total starch content of sunflower seed kernels was 0.067%-0.090%, with the highest total starch content in the small particle size sunflower seed kernels. The content of resistant starch was 0019%-0.032%, and the sunflower seed kernels with medium particle size had the highest resistant starch content.

针对我国装配式钢结构建筑推广应用过程中的标准化、模块化和产业化需求,提出了一种竖向承重体系和抗侧力体系相分离的新型组合结构体系,并基于这一概念提出了一系列适用于多层和高层住宅建筑的高性能结构方案。通过大比例试验、高效数值模拟和性能评价等方法对该种新型体系的抗震性能开展了深入研究,充分证明了其在地震区应用的可行性。另外,开展了与该新型结构体系相配套的集成式楼盖和一体化外围护墙板的研究,分别围绕集成式楼盖及节点的力学机理和一体化外围护墙板的保温性能、隔声性能、受弯性能以及与结构的协同受力性能展开了系列研究。目前,与装配式板柱钢结构体系相配套的一个示范产业园区和两条示范生产线均已建成,相关研发成果已成功应用在两项示范工程中,取得了良好的示范效果。

为了解决电动汽车的车载电池体积大和里程焦虑等问题，加速电动汽车的推广应用，动态无线充电系统（DWCS）应运而生。介绍了电动汽车智能DWCS的基本框架，从电路结构及系统建模、电动汽车定位、DWCS的控制策略以及与智能电网的相互影响等方面详细阐述了国内外学者在 DWCS 方面的研究工作，然后从系统结构及优化、与无人驾驶技术的融合以及电网和交通网的协同优化策略等方面对电动汽车智能 DWCS 未来的研究方向和发展趋势进行了展望。

35kV交流汇集是目前海上风电场集电系统的通用集电方案。随着对海上风场单位成本降低的追求和技术的发展，海上风机单机容量越来越大。然而，由于35kV海底电缆热极限和通流能力的限制，单机容量的增大使得单根海缆上可连接的风机数目随之减少。随着海上风电场规模的扩大和单机容量的增加，如果仍采用35kV交流集电方案，海底电缆的数目势必增加，电缆投资及相应工程费用和难度也将增大。据此，提出了66kV交流集电方案，并基于一组典型案例，对35kV和66kV海上风电交流集电方案进行了技术经济性比对。进一步结合未来海上风电的发展趋势讨论了66kV海上风电集电方案的适用性。

1000kV电网和特高压直流需要依靠500kV电网进行有效的承接和分散。以1000kV和500kV母线的短路电流限制为约束条件，分别针对特高压主变独立和互联供电分区的情况，分析特高压主变分区供电能力。首先分析1000kV/500kV典型分区结构所具备的供电能力，然后根据分区供电能力判断可能形成的500kV/220kV分区数目，所有500kV/220kV分区供电能力之和即是1000kV/500kV/220kV3层结构的整体供电能力，1个分区的供电能力范围约为21000～35000 MW。考虑直流接入500kV电网时，可以在原有分区的供电能力上直接叠加直流输入功率需要的500kV/220kV分区供电能力。针对京津唐规划电网饱和负荷水平进行了深入分析，给出2020年京津唐规划电网目标网架的饱和供电能力范围约为110000～120500 MW。

针对电网规划过程中不确定因素的数学模型类型不一致的情况，提出了考虑可再生能源出力概率模型和预测负荷区间模型的输电网规划方法。首先给出了考虑区间数的扩展随机机会约束规划模型；然后建立了以投资成本最小为目标函数，以支路潮流的扩展随机机会测度作为约束条件，同时考虑随机不确定因素和区间不确定因素的输电网规划模型；采用粒子群优化算法优化规划方案，采用准蒙特卡洛模拟和改进的分支定界相结合的方法对规划方案进行安全校验。IEEE RTS-24节点系统和某实际电网的案例结果证明了所提算法的有效性和正确性。

水貂皮是裘皮贸易的主要产品,占世界裘皮贸易总额的70%左右,其价格和销量直接影响全球毛皮业的发展。近10 a来,毛皮价格波动频繁,通过研究2007～2016年哥本哈根拍卖会9月拍卖季和赫尔辛基拍卖会6月拍卖季的水貂皮均价、售出率,采用比较统计法和数字模型法,得出水貂皮价格及销量在2007～2013年总体呈稳步增长趋势,但从2014年开始,世界经济增长趋缓,全球需求结构改变,各行各业均受影响,其中以毛皮行业较为严重,水貂皮价格大幅度下跌,引发市场震动。利用ARIMA模型预测未来水貂皮的价格走势,在此基础上,分析造成皮张价格大幅度变动的原因,同时为中国毛皮行业今后稳步健康发展提出相应建议。

为了减小相干瑞利噪声,提出了一种多波长瑞利和布里渊自外差检测布里渊光时域反射系统。分析了相位调制产生多波长探测光的机理及三波长系统的自外差检测原理;搭建单波长和三波长自外差检测布里渊光时域反射系统,获得了沿光纤的自外差信号功率和布里渊频移。实验结果表明,相对于单波长系统,三波长系统有效地减小了相干瑞利噪声引起的功率波动,信噪比提高近4.56dB;布里渊频移波动的均方根误差降低2.2 MHz。

理论分析了瑞利BOTDA（布里渊光时域分析）传感系统的动态范围,提出了一种采用脉冲编码技术改善系统信噪比从而增大系统动态范围的方法。研究了瑞利BOTDA系统中格雷码和Simplex码的编码和解码原理,通过对瑞利BOTDA系统采用叠加平均法和脉冲编码法后信噪比改善量的分析对比,阐明了脉冲编码技术在增大瑞利BOTDA系统动态范围方面的优越性,并利用Matlab软件进行了仿真验证。仿真结果表明,该编码技术能够明显改善系统信噪比,增大系统的动态范围。

针对卫星激光通信过程中初始捕获产生的相对运动偏移误差,建立了星间激光通信的相对运动补偿模型。该模型只需提供较少的星历表查询,就能得到高精度补偿数据。仿真实验结果表明,该模型可以减小不确定区域扫描过程中产生的偏移误差,在星间激光通信过程中实现了高概率、快速建立激光通信链路。

采用样线法以巢址为指标在红花尔基樟子松林国家级自然保护区对松鼠的生境保护选择进行了定量研究。使用样线法进行调查,共获取147个巢样方和160个对照样方,对每个样方分别测定了8个环境参数。主成分分析结果表明,影响松鼠巢址选择的诸因素重要性依次为:林型、生境的郁闭程度、生境所处坡向坡位。松鼠显著倾向于在利用苔草樟子松林,随机利用其他类型樟子松林,而对杨桦林等则倾向回避。松鼠巢树周围的树木密度和多样性显著高于对照样方。巢址生境多位于南向的中、下坡位。

[目的]通过观察快速衰老小鼠（SAM）在衰老过程中海马中nNOS的分布和表达变化,探讨NO/nNOS在中枢神经系统衰老中的作用。[方法]采用雄性快速衰老亚系8小鼠（SAMP8）及抗快速衰老亚系1小鼠（SAMR1）为研究对象,其中SAMP8为实验组,SAMR1为对照组,每组动物再分为青年组（2月龄）和老年组（10月龄）两组,每个年龄组随机分配6只动物。用免疫组织化学法标记SAM海马中nNOS神经元,观察海马CA1,CA2和CA3区nNOS神经元的形态和分布,并计数nNOS神经元的数量;用RT-PCR法检测海马中nNOSmRNA表达水平（用平均灰度值表示）。 [结果]老龄SAMP8海马中阳性神经元的形态与其它组比较无明显差别,但CA1和CA2区阳性神经元密度明显减低,CA3区阳性神经元密度无明显改变。SAMP8老年组与青年组相比,海马CA1和CA2区nNOS阳性细胞的数量显著减少（73±14vs144±38,P〈0.01;71±30vs126±39,P〈0.05）,CA3区阳性神经元数量无显著差别;SAMP8与SAMR1比较,青年组海马nNOS阳性细胞的数量无显著差别,老年组海马CA1和CA2区阳性细胞的数量显著减少（73±14vs139±24,P〈0.01;71±30vs120±37,P〈0.05）。SAMP8老年组海马nNOSmRNA水平明显低于青年组（0.43±0.17vs0.92±0.15,P〈0.01）,且低于相应月龄SAMR1（0.43±0.17vs0.86±0.13,P〈0.01）。[结论]海马中nNOS催化产生不足量NO可能加速SAMP8衰老,致使学习记忆能力下降,为通过调节NO产量来延缓衰老及衰老相关学习记忆能力下降提供了理论依据。

非洲冠鹤在中国各动物园中饲养展出较普遍,是观赏价值高、深受游客喜爱的鸟类之一。利用同1对亲鸟为实验对象,经过近10 a的实践,采用不同的繁殖方法进行非洲冠鹤的繁殖实验,最终繁殖成活非洲冠鹤19只。本文从成本投入及最终产出等方面对几种繁殖方式进行了深入的对比和总结,阐明了各种繁殖方式的优势与不足,以期为处在不同发展阶段的野生动物保护单位或部门结合自己的实际情况保护资源、利用资源提供一些参考;同时也为类似物种的繁衍、保护提供一些借鉴。

摘 要 以HCV NS3区单克隆抗体、LSAB法检测了116 例各类肝病肝组织(其中肝细胞癌52 例,肝炎 后肝硬化16 例,慢性肝炎40 例,体质性黄疸8 例)及6 份正常肝组织(作为对照)中HCV 抗原的表达状况,结 果表明, HCV 抗原在肝细胞癌、肝炎后肝硬化及慢性肝炎中检出率分别为13. 5% ( 7 /52)、12. 5% ( 2 /16)、10% ( 4 /40) ,而在体质性黄疸及正常肝组织中未检出HCV抗原。HCV抗原可见于癌细胞或癌周肝细胞的胞浆或胞 核中,实验结果支持HCV 与肝细胞癌的关联, HCV感染对促使肝病的加重也具有一定影响。肝细胞癌中,胞核 型HCV 抗原表达较多见。癌周组织中HCV 抗原检出率高于癌组织,提示HCV 可能主要作用于癌前病变,在肝 细胞癌发生的初始阶段起作用,促使正常细胞恶性化。

2004年9月,中央电视台的一则新闻引起了我的注意,大意是中国西部野生动物保护成果显著,岩羊数量急剧增加,目前每平方公里分布数量为世界前列。我因此想起了银川中广网4月9日发表的一篇郭长江记者的报道,说距离宁夏回族自治区首府银川市仅30多公里的贺兰山国家级保护

世界上很多国家和政府为了普及爱鸟常识和提高人民对鸟的保护意识,根据本国的季节气候规定了爱鸟日、爱鸟节或爱鸟周,爱鸟月。 中国是世界上鸟类资源最丰富的国家之一,现有鸟类1294种。据不完全统计,我国有褐马鸡、朱鹮、中华秋沙鸭等特产珍稀鸟类50种以上。世界上的鹤类有15种,我国就有9种;野生雉类276种,我国有61种。我国还是亚太地区重要的

朱鹮分布区的气候特征张立新（陕西汉中地区气象局）１．资料来源朱鹤的数量分布等引自陕西省外损保护观察站，气象资料抄自汉中地区气象局，部分乡降水观测点资料引自汉中地区农业气候区划，卫星遥感资料引自陕西省农业遥感信息中心。２．朱鹤的分布２．ｌ行政分布：据陕...

BACKGROUND: According to existing clinical studies, vertebroplasty treatment with both the external pedicle approach and the pedicle approach can improve the pain and quality of life of patients with spinal compression fractures. Compared with the pedicle approach, the external pedicle approach has a freer puncture angle, and good bone cement dispersion effect can be obtained by adjusting the puncture angle. OBJECTIVE: To compare the impact of vertebroplasty through individualized unilateral external pedicle approach and bilateral pedicle approach on the treatment of spinal compression fractures by quantifying the dispersion effect of bone cement. METHODS: A total of 80 patients with thoracolumbar compression fracture were divided into two groups by random number table method. The bilateral pedicle group (n=40) underwent vertebroplasty through a bilateral pedicle approach, while the unilateral external pedicle group (n=40) underwent individualized vertebroplasty through a unilateral external pedicle approach. Anteroposterior and lateral X-rays of the affected vertebrae from two groups of patients were photographed to assess effect and type of bone cement dispersion within 3 days after surgery. Visual analog scale score, tenderness threshold around fracture, and Oswestry dysfunction index were assessed before, 1, 7 days, and 1 month after surgery. RESULTS AND CONCLUSION: (1) Dispersion effect of bone cement in unilateral external pedicle group was better than that in bilateral pedicle group (P < 0.001), and the amount of bone cement perfusion was higher than that in bilateral pedicle group (P < 0.001). In the bilateral pedicle group, the bone cement dispersion types were mainly concentrated in type I and type III, while in the unilateral external pedicle group, the bone cement dispersion types were mainly concentrated in type I and type II, and there was a significant difference in bone cement dispersion types between the two groups (P < 0.001). (2) Postoperative visual analog scale scores and Oswestry disability index of both groups were lower than those before surgery (P < 0.001), and postoperative tenderness threshold around fracture showed a trend of decreasing first and then increasing. At the same time point after treatment, there were no significant differences in visual analog scale score, Oswestry disability index, and tenderness threshold around fracture between the two groups (P > 0.05). (3) The results indicate that individualized vertebroplasty via unilateral external pedicle approach can achieve better bone cement dispersion, and the treatment effect is consistent with the vertebroplasty via classical bilateral pedicle approach. [ABSTRACT FROM AUTHOR]

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