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Nutrient resorption strategies of three oak tree species in response to interannual climate variability

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Forest Ecosystems 2021年第4期8卷 937-947页

作者： baoming du Huawei Ji Shirong Liu Hongzhang Kang Shan Yin Chunjiang Liu School of Agriculture and Biology Shanghai Jiao Tong University200240 ShanghaiChina Key Laboratory of Forest Ecology and Environment China’s State Forestry AdministrationResearch Institute of Forest EcologyEnvironment and ProtectionChinese Academy of Forestry100091 BeijingChina Shanghai Urban Forest Ecosystem Research Station State Forestry Administration200240 ShanghaiChina Shanghai Yangtze River Delta Eco-environmental Change and Management Observation and Research Station Ministry of Science and Technology200240 ShanghaiChina

Background:Nutrient resorption is critical for plants toward balancing their nutritional requirements and adapting to environmental variabilities,which further impacts litter quality and nutrient ***,the interannual variability of nutrient resorption under climate change remains ***:We investigated the five-year nutrient resorption efficiencies(NuRE,%)of 14 elements in three deciduous oak tree species(Quercus aliena ***,***,and ***)in a warm-temperate forest of Central China and assessed their relationships with interannual climate and soil ***:Nutrient resorption did not differ between species but varied significantly between different *** each year,N,P,S,K,C,Mg,and Zn were preferentially resorbed in all of the oak species in contrast to Ca,Na,Mn,Ba,Al,Fe,Cu,which were to some extent *** the 14 elements,the NuRE of C,N,P,S,Ca,and Mg was more sensitive to interannual climate variations in the three oak *** carbon resorption efficiency was significantly increased during the driest year of the study(2014);N resorption efficiency was reduced with temperature;whereas N and P resorption efficiency initially decreased and then increased with ***,the elements with higher NuREs typically had lower coefficient of variation(CV)in all three oak ***:Different oak species exhibited analogous nutrient conservation strategies in response to annual climate variabilities,and interannual climate variations strongly impacted plant nutrient *** plants may establish a tradeoff mechanism to rebalance somatic nutrients for regrowth at the end of the growing season.

关键词： Nutrient resorption Tradeoff mechanism Climate change Quercus spp. Temperate forests

Nutrient retranslocation strategies associated with dieback of Pinus species in a semiarid sandy region of Northeast China

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Forest Ecosystems 2023年第6期10卷 763-773页

作者： Chang Liu Kai Wang Hongzhang Kang baoming du Risheng Zhang Shanshan Tai Liaoning Technical University Fuxin123000China College of Environmental Sciences and Engineering Liaoning Technical UniversityFuxin 123000China School of Design Shanghai Jiao Tong UniversityShanghai 200240China Qingyuan Forest National Observation and Research StationShenyang 110016China School of Agriculture and Biology Shanghai Jiao Tong UniversityShanghai 200240China Liaoning Institute of Sandy Land Control and Utilization Fuxin 123000China

In the semiarid sandy region of Northeast China,Mongolian pine(Pinus sylvestris ***)suffers dieback after the age of 35,while Japanese red pine(Pinus densiflora)and Chinese pine(Pinus tabuliformis)stay *** nutrient retranslocation reflects the nutrient conservation and utilization mechanism of plants in response to their ***,the nutrient retranslocation strategies employed by three Pinus tree species to cope with nutrient limitations remain largely *** this study,we investigated the seasonal variations in nitrogen(N)and phosphorus(P)concentrations of Mongolian pine,Japanese red pine,and Chinese pine plantations in terms of the green needles of all ages,senesced needles,and ***,the N retranslocation efficiency(NRE),and P retranslocation efficiency(PRE),and correlations between the N:P ratios of needles and soil were *** results showed that,except for the spring NRE in 1-year-old needles of Mongolian pine,the spring NRE and PRE in 1-and 2-year-old needles of the three tree species were greater than *** autumn PRE was higher than zero for Mongolian pine,but lower than zero for Japanese red pine and Chinese *** the three Pinus species,Mongolian pine showed greater spring PRE in 2-year-old needles,and PRE from 1-to 2-yearold needles,and from 2-year-old needles to ***,Japanese red pine had higher P concentrations and lower N:P ratios in senesced needles,while greater PRE was found in Chinese pine *** relationships between the N:P ratios were found in the current year and 1-year-old needles and soil in the Mongolian pine plantation,while there was an insignificant relationship between the N:P ratios of the needles and soil in the Chinese pine ***,for Mongolian pine,the removal of P from needles in autumn,and higher P translocation from older needles under P-deficient soil may have contributed to the tree *** contrast,Japanese red pine and Chinese pine stored

关键词： Nutrient use strategy Nutrient limitation Seasonal retranslocation Needle age Shelter forest decline

Responses of runoff to changes in climate and human activities in the Liuhe River Basin, China

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Journal of Arid Land 2024年第8期16卷 1023-1043页

作者： LI Mingqian WANG He du Wei GU Hongbiao ZHOU Fanchao CHI baoming School of Ecology and Environment Institute of Disaster PreventionLangfang 065201China Hebei Key Laboratory of Resource and Environmental Disaster Mechanism and Risk Monitoring Sanhe 065201China Suzhou Qianxing Environmental Engineering Co. Ltd.Suzhou 215000China College of Transportation Engineering Nanjing Tech UniversityNanjing 210000China Tianjin North China Geological Exploration General Institute Tianjin 300000China

Since the 1950s,numerous soil and water conservation measures have been implemented to control severe soil erosion in the Liuhe River Basin(LRB),*** these measures have protected the upstream soil and water ecological environment,they have led to a sharp reduction in the downstream flow and the deterioration of the river ecological ***,it is important to evaluate the impact of soil and water conservation measures on hydrological processes to assess long-term runoff *** the Soil and Water Assessment Tool(SWAT)models and sensitivity analyses based on the Budyko hypothesis,this study quantitatively evaluated the effects of climate change,direct water withdrawal,and soil and water conservation measures on runoff in the LRB during different periods,including different responses to runoff discharge,hydrological regime,and flood *** runoff series were divided into a baseline period(1956-1969)and two altered periods,i.e.,period 1(1970-1999)and period 2(2000-2020).Human activities were the main cause of the decrease in runoff during the altered periods,contributing 86.03%(-29.61 mm),while the contribution of climate change was only 13.70%(-4.70 mm).The impact of climate change manifests as a decrease in flood volume caused by a reduction in precipitation during the flood *** of two flood cases indicated a 66.00%-84.00%reduction in basin runoff capacity due to soil and water conservation measures in the upstream *** and water conservation measures reduced the peak flow and total flood volume in the upstream runoff area by 77.98%and 55.16%,respectively,even with nearly double the *** runoff coefficient in the reservoir area without soil and water conservation measures was 4.0 times that in the conservation *** results contribute to the re-evaluation of soil and water conservation hydrological effects and provide important guidance for water resource planning and water conservation policy formu

关键词： runoff soil and water conservation climate variability flood human activities Liuhe River Basin

An internal ballistic model of electromagnetic railgun based on PFN coupled with multi-physical field and experimental validation

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Defence Technology（防务技术） 2024年第2期32卷 254-261页

作者： Benfeng Gu Haiyuan Li baoming Li National Key Laboratory of Transient Physics Nanjing University of Science and TechnologyNanjing 210094China

To accelerate the practicality of electromagnetic railguns,it is necessary to use a combination of threedimensional numerical simulation and experiments to study the mechanism of bore *** this paper,a three-dimensional numerical model of the augmented railgun with four parallel unconventional rails is introduced to simulate the internal ballistic process and realize the multi-physics field coupling calculation of the rail gun,and a test experiment of a medium-caliber electromagnetic launcher powered by pulse formation network(PFN)is carried *** test methods such as spectrometer,fiber grating and high-speed camera are used to test several parameters such as muzzle initial velocity,transient magnetic field strength and stress-strain of *** the simulation results and experimental data,the damage condition of the contact surface is analyzed.

关键词： Internal ballistic modeling Electromagnetic rail gun Multi-physics field coupling Experimental validation PFN

Dietary fat supplementation relieves cold temperature-induced energy stress through AMPK-mediated mitochondrial homeostasis in pigs

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Journal of Animal Science and Biotechnology 2024年第4期15卷 1669-1687页

作者： Wei He Xinyu Liu Ye Feng Hongwei Ding Haoyang Sun Zhongyu Li baoming Shi College of Animal Science and Technology Northeast Agricultural University600 Changjiang StreetHarbin 150030PR China

Background Cold stress has negative effects on the growth and health of mammals, and has become a factor restricting livestock development at high latitudes and on plateaus. The gut-liver axis is central to energy metabolism, and the mechanisms by which it regulates host energy metabolism at cold temperatures have rarely been illustrated. In this study, we evaluated the status of glycolipid metabolism and oxidative stress in pigs based on the gut-liver axis and propose that AMP-activated protein kinase(AMPK) is a key target for alleviating energy stress at cold temperatures by dietary fat *** Dietary fat supplementation alleviated the negative effects of cold temperatures on growth performance and digestive enzymes, while hormonal homeostasis was also restored. Moreover, cold temperature exposure increased glucose transport in the jejunum. In contrast, we observed abnormalities in lipid metabolism, which was characterized by the accumulation of bile acids in the ileum and plasma. In addition, the results of the ileal metabolomic analysis were consistent with the energy metabolism measurements in the jejunum, and dietary fat supplementation increased the activity of the mitochondrial respiratory chain and lipid metabolism. As the central nexus of energy metabolism, the state of glycolipid metabolism and oxidative stress in the liver are inconsistent with that in the small intestine. Specifically, we found that cold temperature exposure increased glucose transport in the liver, which fully validates the idea that hormones can act on the liver to regulate glucose output. Additionally, dietary fat supplementation inhibited glucose transport and glycolysis, but increased gluconeogenesis, bile acid cycling, and lipid metabolism. Sustained activation of AMPK, which an energy receptor and regulator, leads to oxidative stress and apoptosis in the liver;dietary fat supplementation alleviates energy stress by reducing AMPK *** Cold s

关键词： Apoptosis Cold temperature Energy stress Fat Glucolipid metabolism Mitochondrial homeostasis

Microarrow sensor array with enhanced skin adhesion for transdermal continuous monitoring of glucose and reactive oxygen species

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Bio-Design and Manufacturing 2024年第1期7卷 14-30页

作者： Xinshuo Huang baoming Liang Shantao Zheng Feifei Wu Mengyi He Shuang Huang Jingbo Yang Qiangqiang Ouyang Fanmao Liu Jing Liu Hui-jiuan Chen Xi Xie State Key Laboratory of Optoelectronic Materials and Technologies School of Electronics and Information TechnologyGuangdong Province Key Laboratory of Display Material and TechnologySun Yat-Sen UniversityGuangzhou 510006China School of Biomedical Engineering Sun Yat-Sen UniversityShenzhen 518107China Pazhou Lab Guangzhou 510330China The First Affiliated Hospital of Sun Yat-Sen University Guangzhou 510006China

Conventional blood sampling for glucose detection is prone to cause pain and fails to continuously record glucose fluctuations in *** glucose monitoring based on implantable electrodes could induce pain and potential tissue inflammation,and the presence of reactive oxygen species(ROS)due to inflammationmay affect glucose *** technology is less invasive,yet microneedle adhesion with skin tissue is *** this work,we developed a microarrow sensor array(MASA),which provided enhanced skin surface adhesion and enabled simultaneous detection of glucose and H_(2)O_(2)(representative of ROS)in interstitial fluid in *** microarrows fabricated via laser micromachining were modified with functional coating and integrated into a patch of a three-dimensional(3D)microneedle *** to the arrow tip mechanically interlocking with the tissue,the microarrow array could better adhere to the skin surface after penetration into *** MASA was demonstrated to provide continuous in vivo monitoring of glucose and H_(2)O_(2) concentrations,with the detection of H_(2)O_(2) providing a valuable reference for assessing the inflammation ***,the MASA was integrated into a monitoring system using custom *** work provides a promising tool for the stable and reliable monitoring of blood glucose in diabetic patients.

关键词： Microarrow sensor array Glucose sensing Reactive oxygen species sensing Integrated system Continuous monitoring

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4种藤本植物的抗旱性比较

江苏农业学报 2016年第3期32卷 674-679页

作者：周军武金翠杜宝明李彭丽苏州农业职业技术学院江苏苏州215008 上海交通大学上海200240

以4种藤本植物的2年生实生苗为材料,采用盆栽试验方法,观测4种藤本植物的生长指标及形态特征,测定干旱胁迫对4种藤本植物叶片相关生理生化指标的影响。结果表明,干旱胁迫下,美国凌霄的细胞膜透性和丙二醛含量增加最快,常春藤的脯氨酸含... 详细信息

以4种藤本植物的2年生实生苗为材料,采用盆栽试验方法,观测4种藤本植物的生长指标及形态特征,测定干旱胁迫对4种藤本植物叶片相关生理生化指标的影响。结果表明,干旱胁迫下,美国凌霄的细胞膜透性和丙二醛含量增加最快,常春藤的脯氨酸含量增加最快;随着干旱时间持续,美国凌霄的超氧化物歧化酶(SOD)活性持续下降,常春藤的SOD活性变化较平缓,花叶络石和黄金络石的各指标变化趋势都居于中间。模糊数学隶属函数法综合评价,4种藤本植物抗旱能力大小顺序为常春藤>黄金络石>花叶络石>美国凌霄。

关键词：藤本植物抗旱性生长指标形态特征生理生化指标

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面向带宽受限场景的高效语义通信方法

西安电子科技大学学报 2024年第3期51卷 9-18页

作者：刘伟王孟洋白宝明西安电子科技大学通信工程学院陕西西安710071

语义通信为通信系统优化和性能提升提供了新的研究角度,然而,目前语义通信的研究忽略了通信开销的影响,未考虑语义通信性能和通信开销的关系,导致带宽资源受限时语义通信性能难以提升。为此,针对带宽受限场景,提出一种基于信息瓶颈的语... 详细信息

语义通信为通信系统优化和性能提升提供了新的研究角度,然而,目前语义通信的研究忽略了通信开销的影响,未考虑语义通信性能和通信开销的关系,导致带宽资源受限时语义通信性能难以提升。为此,针对带宽受限场景,提出一种基于信息瓶颈的语义通信方法。首先,该方法采用Transformer模型进行语义和信道联合编解码,并设计特征选择模块以识别和删除冗余语义信息,构建了端到端语义通信模型;进而考虑语义通信性能与通信开销之间的折衷关系,基于信息瓶颈理论设计损失函数,在保证语义通信性能的同时,降低通信开销,完成语义通信模型的训练和优化。实验结果显示,在欧洲议会平行语料库上,与基线模型相比,所提方法在保证通信性能的同时可降低约20%~30%的通信开销,在相同带宽条件下该方法的BLEU分数可提升约5%。实验结果表明,所提方法可以有效降低语义通信开销,从而提升带宽资源受限场景下的语义通信性能。

关键词：语义通信通信系统深度学习 Transformer 特征选择模块信息瓶颈理论

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官民互济视角下中国近代文白变革

史学月刊 2024年第5期 41-54页

作者：张宝明河南大学历史文化学院暨中国近现代社会转型研究中心河南开封475001

一个国家民族的语言不仅仅是人际沟通的工具,也内蕴着一个国家民族的道统与文脉。不管是古代中国以“雅言”为尚的语言传统还是近代中国以“白话”为尚的语言变革,都承担着“文以载道”的道统意识,关涉官民互济的文脉建构问题。面对帝... 详细信息

一个国家民族的语言不仅仅是人际沟通的工具,也内蕴着一个国家民族的道统与文脉。不管是古代中国以“雅言”为尚的语言传统还是近代中国以“白话”为尚的语言变革,都承担着“文以载道”的道统意识,关涉官民互济的文脉建构问题。面对帝国列强的武力侵略和欧风美雨的文化渗透,朝野双方在互动中将文言/白话打造成“国文”“国语”建构起的新的语言统绪,以凝聚民族认同,应对文教危机。学统、政统与道统历来是语言与文脉绕不开的命题,及至近代文白变革朝野互动更显其缠绕与紧张。在官民互济视野下反思汉语之文化复兴之路,我们会清晰地看到现代性演进过程中,语言统绪所面临的紧张与焦虑。

关键词：官民互济道统文脉文白变革