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Dynamics of Environmental Humidity and Water Content in Tobacco Leaf and Metabolism of Starch During Curing

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Agricultural Sciences in China 2003年第2期2卷 149-153页

作者： gongchang－rong CHENJiang－hua 等 DepartmentofAgriculture HenanAgriculturalUniversityZhengzhou450002P.R.China ChinaNationalTobaccoLeafCorporation Beijing100055P.R.China

Effect of environmental humidity and water content in tobacco leaf on starch metabolism was studied by using the electric-heated auto-controlled flue-curing barn supplied by Henan Agricultural University, China. The results indicated that the degradation of starch and decrease of water content in tobacco leaf during early yellowing at low humidity was the most rapid, and the water loss was the highest while the lowest under high humidity. The duration for starch degradation under low humidity was longer than that of CK. So the starch residue in cured leaf of different treatment took the order of high humidity yellowing treatment> low humidity yellowing treatment > CK. When the leaf water content was decreased to around 50 %, the starch degradation became slow and the content of starch was stable. Starch degradation and decrease of leaf water content was not synchronous. Starch in tobacco leaf during yellowing degraded more rapidly when humidity was decreased at a high speed, but the degradation stopped earlier at late stage. There was a quicker and higher degradation of starch under high environmental humidity. When the humidity decreased to 70 %, the content of starch was stable. The activity of amylase began to decrease when relative humidity was below 75 %, but it kept a high level of activity when the environmental humidity was below 70 %.

关键词： Tobacco leaf Flue-curing Starch Relative humidity Amylase

Studies on Amylase and Degradation of Starch and Pigment of Tobacco Leaf During Process of Flue-Curing

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Agricultural Sciences in China 2004年第12期3卷 931-936页

作者： gongchang-rong YUANHong-tao CHENJiang-hua SONGZhao-peng HenanAgriculturalUniversity Zhengzhou450002P.R.China HubeiTobaccoProduction＆SalesCorporation Wuhan453000P.R.China ChinaNationalTobaccoLeafCorporation Beijing100055P.R.China

The changes in the activity of amylase and amylase-isoenzyme and the degradation of starch and pigment of tobacco leaf during flue-curing were studied by using the electric- heated flue-curing barn designed and made by the Henan Agricultural University. The temperature and humidity of the barn were controlled automatically. The results indicated that starch in tobacco leaf decreased rapidly and leveled off after 48 h of curring, in the meantime, the content of soluble sugar increased accordingly and reached a peak at the stage of color-fixing. Both of them had a rapid-changing stage in the first 36 hours of yellowing. The changes of starch and soluble sugar contents had highly significant negative-correlation at 1 % level (rNC89 = -0.8962**, rYY85 = -0.9704**). The activity of amylase increased with the proceeding of curing and reached a peak after 36 hours of curing, then decreased. But the activity of amylase kept at a high level when the humidity of curing-environment was very low, even if the tobacco leaf had been dried. The rapid degradation of starch showed a significantly negative correlation with the increase of activity of amylase at 5 % level (rNC89 = -0.8495*, rYY85 = -0.7839*). The degradation of starch and pigment had the same regulation and had highly significant correlation at 1 % level (rNC89= 0.9649**, rYY85= 0.9428**). There were mainly three amylase-isoenzyme bands -A, B, C respectively, in tobacco leaf during flue curing. They were identified as α-AMY, β-AMY, R-AMY, and the activity of β-AMY was the highest. The changes in amylase activity and contents of starch and pigment were affected by the tobacco leaf moisture and environmental humidity during curing.

关键词： Tobacco leaf Flue-curing Starch Amylase Pigment

PD-YOLO:Colon Polyp Detection Model Based on Enhanced Small-Target Feature Extraction

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Computers, Materials & Continua 2025年第1期82卷 913-928页

作者： Yicong Yu Kaixin Lin Jiajun Hong rong-Guei Tsai Yuanzhi Huang New Engineering Industry College Putian UniversityPutian351100China Engineering Research Center of Big Data Application in Private Health Medicine(Putian University) Fujian Province UniversityPutian351100China Computer College Guangdong University of Science&TechnologyDongguan523668China

In recent years,the number of patientswith colon disease has increased *** polyps are the precursor lesions of colon *** not diagnosed in time,they can easily develop into colon cancer,posing a serious threat to patients’lives and health.A colonoscopy is an important means of detecting colon ***,in polyp imaging,due to the large differences and diverse types of polyps in size,shape,color,etc.,traditional detection methods face the problem of high false positive rates,which creates problems for doctors during the diagnosis *** order to improve the accuracy and efficiency of colon polyp detection,this question proposes a network model suitable for colon polyp detection(PD-YOLO).This method introduces the self-attention mechanism CBAM(Convolutional Block Attention Module)in the backbone layer based on YOLOv7,allowing themodel to adaptively focus on key information and ignore the unimportant *** help themodel do a better job of polyp localization and bounding box regression,add the SPD-Conv(Symmetric Positive Definite Convolution)module to the neck layer and use deconvolution instead of *** results indicate that the PD-YOLO algorithm demonstrates strong robustness in colon polyp *** to the original YOLOv7,on the Kvasir-SEG dataset,PD-YOLO has shown an increase of 5.44 percentage points in AP@0.5,showcasing significant advantages over other mainstream methods.

关键词： Polyp detection YOLOv7 SPD-Conv CBAM deconvolution

High-throughput screening of CO_(2) cycloaddition MOF catalyst with an explainable machine learning model

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Green Energy & Environment 2025年第1期10卷 132-138页

作者： Xuefeng Bai Yi Li Yabo Xie Qiancheng Chen Xin Zhang Jian-rong Li Beijing Key Laboratory for Green Catalysis and Separation and Department of Chemical Engineering College of Materials Science&EngineeringBeijing University of TechnologyBeijing100124China

The high porosity and tunable chemical functionality of metal-organic frameworks(MOFs)make it a promising catalyst design ***-throughput screening of catalytic performance is feasible since the large MOF structure database is *** this study,we report a machine learning model for high-throughput screening of MOF catalysts for the CO_(2) cycloaddition *** descriptors for model training were judiciously chosen according to the reaction mechanism,which leads to high accuracy up to 97%for the 75%quantile of the training set as the classification *** feature contribution was further evaluated with SHAP and PDP analysis to provide a certain physical understanding.12,415 hypothetical MOF structures and 100 reported MOFs were evaluated under 100℃ and 1 bar within one day using the model,and 239 potentially efficient catalysts were *** them,MOF-76(Y)achieved the top performance experimentally among reported MOFs,in good agreement with the prediction.

关键词： Metal-organic frameworks High-throughput screening Machine learning Explainable model CO_(2)cycloaddition

Enantioselective reductive conjugate alkenylation of α,β-enones with keto alkenyl acetates by nickel catalysis

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Science China Chemistry 2025年第1期68卷 157-162页

作者： rong-De He Yun-Lei Luo Qiu-Quan Pan Qi-Wei Yao Xing-Zhong Shu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University

Reactions involving alkenyl acetates offer cost-effective and environmentally friendly routes for alkene synthesis, yet their asymmetric variant remains elusive. Concurrently, asymmetric conjugate alkenylation predominantly centered on nucleophilic addition using alkenyl–M. This manuscript presents an asymmetric reductive conjugate alkenylation reaction involving alkenyl acetates. The method facilitates the enantioselective addition of keto alkenyl groups to α,β-enones, resulting in the formation of unsaturated diketones—a class of useful structural motifs that are challenging to access otherwise. The use of electron-rich Pyroxy ligand is essential for achieving both high reaction efficiency and enantioselectivity.

关键词： nickel alkenylation asymmetric cross-coupling alkenes

Recent Advances in Artificial Sensory Neurons:Biological Fundamentals,Devices,Applications,and Challenges

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Nano-Micro Letters 2025年第3期17卷 168-216页

作者： Shuai Zhong Lirou Su Mingkun Xu Desmond Loke Bin Yu Yishu Zhang rong Zhao Guangdong Institute of Intelligence Science and Technology HengqinZhuhai 519031People’s Republic of China College of Integrated Circuits Zhejiang UniversityHangzhou 3112000People’s Republic of China ZJU-Hangzhou Global Scientific and Technological Innovation Center Hangzhou 310027People’s Republic of China Department of Science Mathematics and TechnologySingapore University of Technology and DesignSingapore 487372Singapore Department of Precision Instruments Tsinghua UniversityBeijing 100084People’s Republic of China Center for Brain‑Inspired Computing Research Tsinghua UniversityBeijing 100084People’s Republic of China IDG/McGovern Institute for Brain Research Tsinghua UniversityBeijing 100084People’s Republic of China

Spike-based neural networks,which use spikes or action potentialsto represent information,have gained a lot of attention because of their high energyefficiency and low power *** fully leverage its advantages,convertingthe external analog signals to spikes is an essential *** including analog-to-digital converters or ring oscillators,and sensorssuffer from high power and area *** efforts are devoted to constructingartificial sensory neurons based on emerging devices inspired by the biologicalsensory *** can simultaneously perform sensing and spike conversion,overcoming the deficiencies of traditional sensory *** review summarizesand benchmarks the recent progress of artificial sensory *** starts with thepresentation of various mechanisms of biological signal transduction,followed bythe systematic introduction of the emerging devices employed for artificial ***,the implementations with different perceptual capabilitiesare briefly outlined and the key metrics and potential applications are also ***,we highlight the challenges and perspectives for the future development of artificial sensory neurons.

关键词： Artificial intelligence Emerging devices Artificial sensory neurons Spiking neural networks Neuromorphic sensing

Direct and rapid detection of serum amino acid and monoamine neurotransmitters to assist the diagnosis of panic disorder

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Science China Chemistry 2025年第1期68卷 377-384页

作者： Shiwen Liu Xuerui Wan Meng Zhao Jiaqi Wang Weilan Wu Linlin You Yonggui Yuan Qian Xu rong Gao Key Laboratory of Environmental Medicine Engineering Ministry of Education School of Public Health Southeast University Key Laboratory of Modern Toxicology of Ministry of Education Department of Hygienic Analysis and Detection School of Public HealthNanjing Medical University Department of Psychosomatics and Psychiatry Zhongda Hospital School of Medicine Southeast University

The measurement of amino acid and monoamine neurotransmitters（NTs） in serum plays a central role in the identification and monitoring of clinical panic disorder（PD）. However, the strong polarity and chemical heterogeneity of NTs make direct extraction and rapid detection extremely challenging. Herein, we developed a strategy that integrated solid phase extraction based on magnetic Fe3O4coated with polydopamine（Fe3O4@PDA） and direct analysis of mass spectrometry in real time（DART-MS） for quantification of 10 NTs. We systematically investigated the optimal conditions of this strategy to achieve good accuracy and precision. Compared with existing magnetic solid phase extraction methods for NTs detection in biological samples, this strategy could adsorb more targets while having similar adsorption efficiencies, and the total process time was reduced by an average of 69.42%. We rapidly determined the metabolic abnormality of 6 types of NTs in the serum of PD patients and demonstrated their diagnostic accuracy. In addition, an outstanding feature of PD in which tryptophan was more metabolized by the KYN pathway and the 5-hydroxytryptamine pathway was inhibited could be elucidated by this strategy. Our results highlighted the potential ability of Fe3O4@PDA coupled with DART-MS to assist in the clinical diagnosis of PD.

关键词： neurotransmitters panic disorder magnetic solid phase extraction direct analysis of mass spectrometry in real time

Federated local causal structure learning

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Science China(Information Sciences) 2025年

作者： Kui YU Chen rong Hao WANG Fuyuan CAO Jiye LIANG School of Computer and Information Hefei University of Technology School of Computer and Information Technology Shanxi University

Local causal structure learning (LCS) efficiently identifies a set of direct neighbors of a specified variable from observational data. Additionally, it distinguishes direct causes and direct effects of this variable without learning the entire causal structure. While many LCS algorithms have been proposed, they do not consider the data privacy-preserving problem,which has attracted extensive attention from academia and industry. To address this issue, we propose a federated local causal structure learning (FedLCS) algorithm to learn local causal structures in privacy-preserving data in a federated ***, FedLCS introduces a layer-wise federated local skeleton learning algorithm to construct the local skeleton. Based on this skeleton, it introduces a federated local skeleton orientation algorithm and an extension-and-backtracking orientation algorithm to orient the edges. Finally, FedLCS uses a federated local extension-and-backtracking orientation algorithm to orient the remaining edges. Extensive experiments on benchmark, synthetic, and real datasets demonstrate that FedLCS can learn the local causal structure of a given variable in a federated setting.

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Inhibiting ceramide synthase 5 expression in microglia decreases neuroinflammation after spinal cord injury

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Neural Regeneration Research 2025年第10期20卷 2955-2968页

作者： Wei Zhang Yubao Lu Ruoqi Shen Yingjie Wu Chenrui Liu Xingxing Fang Liangming Zhang Bin Liu Limin rong Department of Spine Surgery The Third Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina National Medical Products Administration(NMPA)Key Laboratory for Quality Research and Evaluation of Cell Products GuangzhouGuangdong ProvinceChina Guangdong Provincial Center for Quality Control of Minimally Invasive Spine Surgery GuangzhouGuangdong ProvinceChina Guangdong Provincial Center for Engineering and Technology Research of Minimally Invasive Spine Surgery GuangzhouGuangdong ProvinceChina

Microglia,the resident monocyte of the central nervous system,play a crucial role in the response to spinal cord ***,the precise mechanism remains *** investigate the molecular mechanisms by which microglia regulate the neuroinflammatory response to spinal cord injury,we performed single-cell RNA sequencing dataset analysis,focusing on changes in microglial *** found that the MG1 subpopulation emerged in the acute/subacute phase of spinal cord injury and expressed genes related to cell pyroptosis,sphingomyelin metabolism,and neuroinflammation at high ***,we established a mouse model of contusive injury and performed intrathecal injection of siRNA and molecular inhibitors to validate the role of ceramide synthase 5 in the neuroinflammatory responses and pyroptosis after spinal cord ***,we established a PC12-BV2 cell co-culture system and found that ceramide synthase 5 and pyroptosis-associated proteins were highly expressed to induce the apoptosis of neuron *** ceramide synthase 5 expression in a mouse model of spinal cord injury effectively reduced ***,ceramide synthase 5-induced pyroptosis was dependent on activation of the NLRP3 signaling *** ceramide synthase 5 expression in microglia in vivo reduced neuronal apoptosis and promoted recovery of neurological ***2g7 formed a“bridge”between sphingolipid metabolism and ceramide synthase 5-mediated cell death by inhibiting the NLRP3 signaling ***,these findings suggest that inhibiting ceramide synthase 5 expression in microglia after spinal cord injury effectively suppressed microglial pyroptosis mediated by NLRP3,thereby exerting neuroprotective effects.

关键词： ceramide synthase 5 gasdermin D microglia neuroinflammation NLRP3 nuclear factor kappa B Pla2g7 pyroptosis sphingomyelin metabolism spinal cord injury