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AVIAN RESEARCH 2025年第1期16卷

作者： Gao, Lifang Zhang, Wen Zhu, Wenjing Wu, Yichen xu, Ran Sun, Ningning Wang, yujie Jia, Biyun Du, Bo Northwest Normal Univ Coll Life Sci Lanzhou 730070 Peoples R China Lanzhou Univ Sch Life Sci Lanzhou 730000 Peoples R China Lanzhou Univ Coll Ecol Lanzhou 730000 Peoples R China

Inclusive fitness theory posits that altruistic behaviors, which are directed more likely towards relatives, should be favored by natural selection. However, the prevalence of alternative parenting behaviors in offspring selection, including rejecting their own offspring and accepting the offspring of others, remains poorly understood within the context of parental care evolution. In order to investigate the factors that prompt the occurrence of alternative parenting behaviors, we designed a series of experiments in the Azure-winged Magpie (Cyanopica cyanus). By manipulating the nest spatial position or offspring age/number and parent-offspring familiarity, we addressed how parents provided parental care for the manipulated offspring. In the nest resettlement experiment, the probability of parents rejecting their own offspring significantly increased with nest-moving distances while decreased with offspring ages. In the cross-fostering experiments, the probability of parents provisioning unrelated young significantly decreased with the age difference between cross-fostered chicks. In the nest duplication experiments, where parents were given a choice between familiar offspring and unfamiliar unrelated chicks or between unfamiliar offspring and familiar unrelated chicks, the probability of both alternative parenting behaviors was significantly influenced by the time when parental association with their offspring was deprived. We conclude that as offspring phenotypic traits become individualized and fixed at a special developmental stage, parents gradually acquire the capacity for offspring recognition by associating with them. Any factors that disrupt parent-offspring association or introduce unrelated young into the nest prior to this critical timeline can result in the occurrence of alternative parenting behaviors.

关键词： Cross-foster Cyanopica cyanus Offspring recognition Parental care Parent-offspring association

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中国养殖海域利用效率空间非均衡格局及成因

资源科学 2020年第11期42卷 2158-2169页

作者：许瑶纪建悦许玉洁中国海洋大学经济学院青岛266100 中国海洋大学海洋发展研究院青岛266100

提高养殖海域利用效率是实现海域资源可持续发展的关键举措,探究养殖海域利用效率的空间非均衡性及成因,对养殖海域合理开发利用具有重要意义。本文运用超越对数生产函数形式的随机前沿模型对2008—2017年中国10个沿海地区养殖海域利用... 详细信息

提高养殖海域利用效率是实现海域资源可持续发展的关键举措,探究养殖海域利用效率的空间非均衡性及成因,对养殖海域合理开发利用具有重要意义。本文运用超越对数生产函数形式的随机前沿模型对2008—2017年中国10个沿海地区养殖海域利用效率进行测度,综合采用核密度估计、GINI系数、对数离差均值、Theil指数、重心—标准差椭圆方法分析空间非均衡性及空间格局,并进一步对空间非均衡格局成因进行探究。研究发现:①中国沿海地区养殖海域平均利用效率为69.85%,且利用效率在时序和空间上存在较大差异,呈现显著的空间非均衡性。②中国养殖海域利用效率的重心呈现出"先向南—后向北—再向南"的变化格局,南部沿海养殖海域利用效率整体上有所提升。③利用效率空间非均衡格局成因主要包括养殖人员培训水平、推广机构密度、推广人员学历水平、经济发展水平的差异。据此,从深挖低效率地区养殖海域利用效率潜力、制定地方特色的养殖海域开发利用政策、完善海水养殖推广体系三方面提出改善中国养殖海域利用效率空间非均衡格局的相关建议。

关键词：养殖海域利用效率空间非均衡格局成因超越对数生产函数核密度估计

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贮藏对祁门红茶风味品质及化学成分的影响

食品与发酵工业 2025年第4期51卷 177-187页

作者：徐玉婕周汉琛张晓磊刘亚芹雷攀登安徽省农业科学院茶叶研究所安徽黄山245000

为探究贮藏对祁门红茶品质特征的影响,该研究基于感官审评、非挥发性及挥发性物质检测,并结合多元统计分析,分析了祁门红茶低温贮藏(-40℃,1年,DW)、室温贮藏(1年,SW)和室温贮藏后低温短时烘焙(70℃,30 min,HB)处理下滋味、香气成分变... 详细信息

为探究贮藏对祁门红茶品质特征的影响,该研究基于感官审评、非挥发性及挥发性物质检测,并结合多元统计分析,分析了祁门红茶低温贮藏(-40℃,1年,DW)、室温贮藏(1年,SW)和室温贮藏后低温短时烘焙(70℃,30 min,HB)处理下滋味、香气成分变化情况。结果表明,与DW红茶比较,SW红茶品质较佳,滋味醇厚,鲜爽度增加,花果香较显;烘焙后的HB红茶汤滋味鲜爽度、香气品质均下降。3组祁门红茶共检测出60种滋味物质,其中可溶性糖、没食子酸含量在SW红茶中最高,而茶黄素、黄酮醇及黄酮(醇)苷含量在SW红茶中较低。偏最小二乘法判别分析模型(partial least squares-discriminant analysis,PLS-DA)可将3组有效区分,筛选出5种差异滋味成分,分别是咖啡碱、茶氨酸、表儿茶素、没食子酸和表没食子儿茶素。共检测出74种挥发性成分,SW红茶中呈现花香的酮类、烯类以及内酯类化合物含量显著增加。通过PLS-DA可将3组红茶明显区分,筛选出的13种差异香气成分分别是:己酸叶醇酯、β-紫罗酮、正己醛、壬醛、青叶醛、香叶基丙酮、苯甲醛、芳樟醇氧化物Ⅰ、脱氢芳樟醇、月桂烯、己酸己酯、丁酸叶醇酯、2-丁基-2-辛烯醛。该研究为祁门红茶在室温下的短期贮藏及贮藏后的工艺处理提供理论参考与科学依据。

关键词：祁门红茶贮藏低温烘焙感官审评化学成分

The Irradiation Effect of High LET Heavy Ion Beam on Phenylalanine Aqueous Solution

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The Irradiation Effect of High LET Heavy Ion Beam on Phenyla...

Methods Research to Calculate Equivalent of Environmental Cost in Power Industry

21世纪初辐射防护论坛第五次会议

作者： xu yujie (School of Radiation Medicine and Public Health, Soochow University)

The radiation chemistry is the research subject to study the action of ionizing radiation on the materials. The irradiation effects are considered as be induced in two kinds of processes. One is the direct energy deposition or energy transfer, which is the Physical Process. Another is the Chemical Process, the ionizing radiation induce first unstable components that react with the target materials, finally appeared as irradiation effect. The ionizing radiation includes α,β,γ ray, the neutron beam, and the energetic charged particles. The property of the ionizing radiation can be generally indicated by LET (Linear Energy Transfer, the amount of energy deposited per unit path-length of charged particle, -dE/dX). It was well known that the irradiation effect of high-energy ions or neutron beam was different from that of γ-ray or electron beam. The LET of 60Co γ-ray was only 0.3 eV/nm, and the irradiation effect of γ-ray has been studied in detail. The high-energy heavy ion beam has higher LET, which may be several hundreds to thousand eV per nm. When heavy ions passed through the materials, there was non-homogeneous and higher density energy deposition, which was called as "track core" along its trajectory. In the track core, the high-density unstable excited components will react with each other and disappear quickly. About the track structure, there were many reports.

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Journal of Power and Energy Engineering 2014年第4期2卷 86-93页

作者： Wenchang Han Dunnan Liu Yuhong Fan Yu Hu yujie xu Xinming Liu Electric Power Research Institute of Economics and Technology Hubei Electric Power Company Wuhan China School of Economics and Management North China Electric Power University Beijing China

Power industry as an important means of primary energy consumption, occupies an important position in coal consumption and pollutant emissions, and causes a great impact on the environment. It is particularly important to define environmental costs while Environmental costs account for a heavy weight in the total cost of generating after the introduction of the Clean Development Mechanism (CDM) This paper analyzes the composition of environmental cost and its calculation methods, three cost equivalent pricing methods and its scope in environmental costs were proposed, there are Government pricing, market pricing and cost accounting, then analyses the cost of equivalent effect on electricity trade.

关键词： Environmental Costs Cost Equivalent Pricing

Research Electricity Production Costs and External Compensation Mechanism

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Journal of Power and Energy Engineering 2014年第4期2卷 94-102页

作者： Dunnan Liu Xinming Liu Liaoyi Ning Haichao Wang Yu Hu yujie xu North China Electric Power University Economics and Management Beijing China Electric Power Research Institute of Economics and Technology Liaoning Electric Power Company Shenyang China Dispatching Control Center Anhui Electric Power Company Hefei China

China's power enterprises are mainly dominated by thermal power, thermal power is the key industry of coal consumption, so the thermal power enterprises have a fundamental influence on the environment, and how to not affect the vital interests of power enterprises under the condition of power plant to increase the strength of governance is to solve the current problem of letter. On the basis of various types of power generation enterprise environmental cost of thermal power, hydropower, wind power and nuclear power pollutant treatment cost were described, through the analysis of emission control scheme and the cost compensation of pollutants, environmental governance cost model, using a actual plant data, calculation of various pollutants compensation cost of thermal power plant, and according to the thermal power and wind power for quantitative comparison before and after compensation.

关键词： The Cost of Environmental Governance Compensation Mechanism Low Carbon and Energy Saving Pollutant Emission

Power Purchase Model of Provincial Grids Based on Diverse Energy Coordination Hedging Optimization

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Journal of Power and Energy Engineering 2014年第4期2卷 463-469页

作者： Dunnan Liu yujie xu Weimin Zeng Jiangping Liu Min Fan Xinming Liu School of Economics and Management North China Electric Power University Beijing China Hubei Provincial Electric Power Company Power Exchange Center Wuhan China

Under the background of energy conservation, the grid companies should give priority to consumptive hydropower, wind power and other clean electricity to fulfill their social responsibility and promote the carbon emission reduction in power industry. But under the current power purchase mode, grid companies must first perform the contract. This is extremely uneconomical and not environmentally friendly. Based on hedging theory, this paper proposes a power purchase optimization model using the strategy of “compression and compensation”. If outer price is lower than the contract price, the grid can compress contract power appropriately, leaving more space for purchasing electricity;if outer price is not attractive enough, the grid should timely improve contract proportion, compensating the deviations of contract caused by "compression". Based on the strategy of "compression and compensation", it can effectively reduce the abandoned wind and water, enhance the economic and social benefits of provincial power grid.

关键词： Power Purchase Optimization Hedging "Compression and Compensation" Large-Scale System Decomposition-Coordination

Channel-Aware Handover Management for Space-Air-Ground Integrated Networks

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China Communications 2025年第2期22卷 62-76页

作者： Chen Nuo Sun Zhili Song yujie Cao Yue Xia xu Aduwati Binti Sali School of Cyber Science and Engineering Wuhan UniversityWuhan 430000China Institute of Communication Systems University of SurreyGuildford GU27XHU.K. 6G Research Center China Telecom Research InstituteBeijing 102200China Institute for Mathematical Research(INSPEM) Universiti Putra Malaysia(UPM)43400 SerdangSelangorMalaysia

To support ubiquitous communication and enhance other 6G applications,the Space-Air-Ground Integrated Network(SAGIN)has become a research ***,satellite-ground fusion technologies integrate network entities from space,aerial,and terrestrial ***,they face challenges such as spectrum scarcity and inefficient satellite *** paper explores the Channel-Aware Handover Management(CAHM)strategy in SAGIN for data ***,CAHM utilizes the data receiving capability of Low Earth Orbit(LEO)satellites,considering satellite-ground distance,free-space path loss,and channel ***,CAHM assesses LEO satellite data forwarding capability using signal-to-noise ratio,link duration and buffer queue ***,CAHM applies historical data on LEO satellite transmission successes and failures to effectively reduce overall interruption *** results show that CAHM outperforms baseline algorithms in terms of delivery ratio,latency,and interruption ratio.

关键词： channel modeling seamless handover space-air-ground integrated network

The Prospective Association of Family Members' Sugar-sweetened Beverages Intake with Children's Sugar-sweetened Beverages Consumption in China

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The Prospective Association of Family Members' Sugar-sweeten...