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Chinese Journal of Chemistry 2024年第14期42卷 1593-1598页

作者： Kunxiu Shou shanshan liu Yunqin Zhang Guozhi Xiao State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyUniversity of Chinese Academy of SciencesChinese Academy of SciencesKunmingYunnan650201 China

Collective syntheses of *** CPS K43,K47 and K88 repeating units have been accomplished via a newα-glycosylation method with GlcN_(3) as donors,which features:1)mild reaction conditions,2)good to high yields,3)excellent *** synthetic route also highlights an orthogonal one-pot coupling strategy on the basis of glycosyl ortho-(1-phenylvinyl)benzoates for stereoselective constructions of both 1,2-trans and 1,2-cis glycosidic bonds,precluding the issues of aglycone transfer.

关键词： A baumanni CPS α-Glycosylation method One-pot glycosylation 1,2-GlcN bonds Glycosyl ortho-(1-phenylvinyl)benzoates Carbohydrates Oligosaccharides Total synthesis

Safety control strategy of spinal lamina cutting based on force and cutting depth signals

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CAAI Transactions on Intelligence Technology 2024年第4期9卷 894-902页

作者： Jian Zhang Yonghong Zhang shanshan liu Xuquan Ji Sizhuo liu Zhuofu Li Baoduo Geng Weishi Li Tianmiao Wang School of Mechanical Engineering and Automation Beihang UniversityBeijingChina Beijing Zoezen Robot Co.Ltd. BeijingChina Department of Orthopaedics Peking University Third HospitalBeijingChina Engineering Research Center of Bone and Joint Precision Medicine Ministry of EducationBeijingChina Beijing Key Laboratory of Spinal Disease Research BeijingChina School of Biological Science and Medical Engineering Beihang UniversityBeijingChina Department of Biology Kenyon CollegeGambierOhioUSA

Laminectomy is one of the most common posterior spinal operations. Since the lamina is adjacent to important tissues such as nerves, once damaged, it can cause serious com-plications and even lead to paralysis. In order to prevent the above injuries and com-plications, ultrasonic bone scalpel and surgical robots have been introduced into spinal laminectomy, and many scholars have studied the recognition method of the bone tissue status. Currently, almost all methods to achieve recognition of bone tissue are based on sensor signals collected by high‐precision sensors installed at the end of surgical robots. However, the previous methods could not accurately identify the state of spinal bone tissue. Innovatively, the identification of bone tissue status was regarded as a time series classification task, and the classification algorithm LSTM‐FCN was used to process fusion signals composed of force and cutting depth signals, thus achieving an accurate classi-fication of the lamina bone tissue status. In addition, it was verified that the accuracy of the proposed method could reach 98.85% in identifying the state of porcine spinal laminectomy. And the maximum penetration distance can be controlled within 0.6 mm, which is safe and can be used in practice.

关键词： artificial neural network intelligent robots robotics surgery

Lactobacillus melliventris promotes hive productivity and immune functionality in Bombus terrestris performance in the greenhouse

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Insect Science 2024年第3期31卷 911-926页

作者： Qianhui Yu Yan liu shanshan liu Shaogang Li Yifan Zhai Qingchao Zhang Li Zheng Hao Zheng Yifan Zhai Xiaofei Wang Insttute of Plant Protection Shandong Academy of Agricultural SciencesJinanChina Key Laboratory of Natural Enemies Insects Ministry of Agriculture and Rural AffairsJinanChina College of Food Science and Nutritional Engineering China Agricultural UniversityBeijingChina BGI-Qingdao BGI-ShenzhenQingdaoShandongChina

Bumblebees are important pollinators in agricultural ecosystems,but their abundance is declining *** is an urgent need to protect bumblebee health and their pollination *** possess specialized gut microbiota with potential to be used as probiotics to help defend at-risk bumblebee ***,evidence for probiotic benefits on bumblebees is ***,we evaluated how supplementation with Lactobacillus melliventris isolated from bumblebee gut affected the colony development of Bombus *** native strain colonized robustly and persisted long-term in bumblebees,leading to a significantly higher quality of ***,the tyrosine pathway was upregulated in the brain and fat body,while the Wnt and mTOR pathways of the gut were ***,the field experiment in the greenhouse revealed the supplementation of *** led to a 2.5-fold increase in the bumblebee survival rate and a more than 10%increase in the number of flowers visited,indicating a better health condition and pollination ability in field *** study represents a first screening for the potential use of the native gut member,***,as probiotic strains in hive supplement for bumblebee breeding,which may be a practical approach to improve immunity and hive health.

关键词： Bombus terrestris gut microbiota immunity Lactobacillus melliventris transcriptome

Study on the energy level limitations of triplet-triplet annihilation upconversion with anthracene-isomerized dimers as annihilators

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ChemPhysMater

ChemPhysMater 2024年第2期3卷 187-193页

作者： shanshan liu Tingting Gou Xiaojuan Song Riming Hu Heyuan liu Xiyou Li Xuchuan Jiang Institute for Smart Materials&Engineering University of JinanJinan 250022China Schoolof Materials Science and Engineering China University of Petroleum(East China)Qingdao 266580China

The enhancement in the efficiency of triplet-triplet annihilation upconversion(TTA-UC)is mainly determined by the triplet energy transfer(TET)and triplet-triplet annihilation(TTA)between the sensitizers and *** TET process works efficiently by adjusting the concentration ratio of the sensitizers and *** efficiency of TTA is determined by the properties of the *** TTA is a Dexter-type energy transfer and is affected by the diffusion rate,the energy levels of the excited states and the molecular size are both crucial in *** this study,four isomerized dimers of 9,10-diphenlanthracene(DPA)and anthracene(An)were designed and prepared as annihilators for *** singlet and triplet energy levels could be adjusted by altering the connection position while maintaining the molecular weight and *** PtOEP was used as the sensitizer,the maximum upconversion efficiency of 9-[4-(9-anthracenyl)phenyl]-10-phenylanthracene(9DPA-9An)was~11.18%.This is four times higher than that of 9,10-diphenyl-2,9-bianthracene(2DPA-9An,2.63%).The calculation of the energies of T_(1)and the higher triplet state(T_(3),because E(T_(2))is similar to the E(T)of these dimers)for these dimers has provided insights into the underlying *** indicated that the energy gap value of 2×E(T_(1))-E(T_(3))is the determining factor for TTA *** work may provide a better understanding of the excited-state energy levels,which is crucial for designing novel annihilators to enhance the TTA-UCefficiency.

关键词： Upconversion Annihilator Triplet-triplet annihilation Energy levels

A chromosome-level genome of electric catfish(Malapterurus electricus)provided new insights into order Siluriformes evolution

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Marine Life Science & Technology 2024年第1期6卷 1-14页

作者： Meiru liu Yue Song Suyu Zhang Lili Yu Zengbao Yuan Hengjia Yang Mengqi Zhang Zhuocheng Zhou Inge Seim shanshan liu Guangyi Fan Huanming Yang College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China BGI-Qingdao BGI-ShenzhenQingdao 266555China BGI-Shenzhen Shenzhen 518083China Professional Committee of Native Aquatic Organisms and Water Ecosystem of China Fisheries Association Beijing 100125China Integrative Biology Laboratory College of Life SciencesNanjing Normal UniversityNanjing 210023China State Key Laboratory of Agricultural Genomics BGI-ShenzhenShenzhen 518083China

The electric catfish(Malapterurus electricus),belonging to the family Malapteruridae,order Siluriformes(Actinopterygii:Ostariophysi),is one of the six branches that has independently evolved electrical *** assembled a 796.75 Mb *** genome and anchored 88.72%sequences into 28 *** family analysis revealed 295 expanded gene families that were enriched on functions related to glutamate *** evolutionary analyses of electric organs among different lineage of electric fishes further revealed that the coding gene of rho guanine nucleotide exchange factor 4-like(arhgef4),which is associated with G-protein coupled receptor(GPCR)signaling pathway,underwent adaptive parallel *** identification suggests visual degradation in catfishes,and an important role for taste in environmental *** findings fill in the genomic data for a branch of electric fish and provide a relevant genetic basis for the adaptive evolution of Siluriformes.

关键词： Electric fish Karyotype analysis Convergent evolution Environmental adaptation Historical effective population size

Visible-light-induced organocatalyzed C（sp）–H bond functionalization of 1,3-azoles with trifluoroacetylsilanes

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Science China Chemistry 2024年

作者： Zhengyu Li Zeguo Zhang Zhihan Zhang Gang Zhou Yizhi Zhang shanshan liu Xiao Shen The Institute for Advanced Studies Engineering Research Center of Organosilicon Compounds & Materials Ministry of EducationWuhan University College of Chemistry Central China Normal University

Previous carbene insertion to C–H bonds of 1,3-azoles relied on metal carbene species. Herein, we report a metal-free C（sp2）–H bond functionalization of 1,3-azoles with trifluoroacetylsilanes. The reaction features mild conditions, broad substrate scope and wide functional group tolerance. The mechanistic study supports that the success of the reaction is probably attributed to the dual roles of trifluoroacetylsilanes under the photocatalyzed conditions: generating carbenes which undergo cyclopropanation and generating biradicals which promote ring-opening aromatization of the in situ generated fused cyclopropanes.

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Arecoline causes cognitive impairment and potential addiction via disturbing Kenyon cells in bumblebee brain

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Food Science and Human Wellness 2024年

作者： Huiling liu Xiaohuan Mu Rongrong Fan Jieteng Chen Jie Ma Liang Meng Xiaosong Hu Hao Zheng shanshan liu Xiaofei Wang College of Food Science and Nutritional Engineering， National Engineering Research Center for Fruit and Vegetable Processing， Key Laboratory of Fruits and Vegetables Processing， Ministry of Agriculture， Engineering Research Centre for Fruits and Vegetables Processing， Ministry of Education， China Agricultural University BGI-Qingdao

Areca nut is the basic ingredient of betel quid， which is chewed by hundreds of millions of people in south-eastern Asia. Chewing of areca nut has been associated with oral cancers potentially due to its specific alkaloids， among which arecoline constitutes about 90% of total fraction. Being the world’s fourth most commonly used psychoactive substance， arecoline evokes stimulation， addiction， and other direct neurological effects， while its misuse correlates to neurotoxic effects. However， what might underlie its neurotoxic mechanisms has been poorly documented. The brain is encoded by a complex network of neuronal and glial cell types， and neurotoxicity of hazardous compounds present transcriptional heterogeneity. Recently， the eusocial bumblebee has been used as a model for studying brain effects， with sophisticated cognitive capability and precisely measured brain architecture. Here， we decipher cell-type-specific mental risks to arecoline using bumblebees. Arecoline induced locomotor hyperactivity and cognitive impairment. Single nucleus RNA sequencing (snRNA-seq) unearthed arecoline-induced cell-specific responses， primarily targeted on Kenyon cells (KC). Moreover， high-dose arecoline induced distinctive cell responses among KC subtypes， particularly class I large Kenyon cell (lKC)， leading to DNA damage， excitatory/inhibitory (E/I) imbalance， and calcium dyshomeostasis， which potentially resulted in cognitive impairment. Given arecoline’s popularity and growing exposure risks to humans， neurological health risks of areca nut warrant serious consideration.

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一种端到端的事件共指消解方法

工程科学与技术 2024年第1期56卷 82-88页

作者：刘浏蒋国权环志刚刘姗姗刘茗丁鲲国防科技大学第六十三研究所江苏南京210007 宿迁学院信息工程学院江苏宿迁223800

事件共指消解任务主要是判断不同事件提及是否指向同一件事件。事件共指消解不仅能有效缓解事件抽取任务中存在的信息冗余问题,而且为事件内容补全提供了有效途径。尽管许多学者利用深度学习方法对事件共指消解进行了大量研究。但是大... 详细信息

事件共指消解任务主要是判断不同事件提及是否指向同一件事件。事件共指消解不仅能有效缓解事件抽取任务中存在的信息冗余问题,而且为事件内容补全提供了有效途径。尽管许多学者利用深度学习方法对事件共指消解进行了大量研究。但是大部分事件共指消解模型中仍然存在显式信息表示不足、论元噪声引入以及共指事件分布稀疏等问题。针对上述问题,提出了一种利用显式论元信息和重构事件链的端到端事件共指消解方法。首先,使用名为OneIE事件抽取模型提取事件的触发词和论元以获取事件的结构化信息;随后,使用Transformer编码器对事件提及上下文进行表示,并将置信分数引入论元信息编码以缓解其可能带来的误差传递;同时,采用门控机制对论元在触发词的水平和垂直方向上的信息进行分解,并根据论元和触发词的相关系数融合两个方向的信息,过滤论元中的噪声;然后,使用前馈网络计算事件提及对共指得分;最后,通过重构事件链验证事件提及的合法性以纠正由共指事件稀疏性带来的模型训练结果偏差。为了验证方法的有效性,本文基于数据集ACE2005进行实验。结果表明,本文模型在端到端事件共指消解任务上具有一定的先进性,其中CoNLL和AVG指标平均高出基线模型5.67%和6.24%。

关键词：事件共指消解自然语言处理预训练语言模型

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探究重力和单侧光对胚芽鞘弯曲程度的影响

生物学教学 2024年第2期49卷 46-47页

作者：刘闪闪浙江省宁波市鄞州中学宁波315100

阐述了以小麦与玉米胚芽鞘为实验材料,探究重力和单侧光对胚芽鞘弯曲程度的影响。分析实验结果发现,重力对胚芽鞘弯曲的影响要大于单侧光的影响。

关键词：小麦与玉米胚芽鞘重力与单侧光影响程度

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劳动力成本上升与企业创新:负担还是赋能?

现代经济探讨 2024年第8期 85-96页

作者：刘姗姗黄险峰河南师范大学政治与公共管理学院新乡453007 辽宁大学经济学院沈阳110036

创新是引领经济高质量发展的第一动力。在中国老龄化加剧背景下,需要厘清劳动力成本持续上升对企业创新的影响效应,为更好地落实创新驱动战略和推动经济高质量发展提供理论基础和实践启示。利用2007-2022年中国沪深A股上市公司数据,实... 详细信息

创新是引领经济高质量发展的第一动力。在中国老龄化加剧背景下,需要厘清劳动力成本持续上升对企业创新的影响效应,为更好地落实创新驱动战略和推动经济高质量发展提供理论基础和实践启示。利用2007-2022年中国沪深A股上市公司数据,实证分析劳动力成本上升对企业创新的影响,结果表明劳动力成本上升与企业创新数量、创新质量均呈倒U型关系。劳动力成本上升通过影响企业投资、劳动力雇佣和利润率作用于企业创新。劳动力成本上升与企业创新的倒U型关系具体表现为高效率企业、资本密集型企业和非国有企业的促进效应,低效率企业、劳动密集型企业和国有企业的抑制作用。

关键词：劳动力成本创新数量创新质量劳动生产率

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