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Estimation of Apple Tree Leaf Chlorophyll Content Based on Machine Learning Methods

REMotE SENSING 2021年第19期13卷 3902-3902页

作者： Ta, Na Chang, Qingrui Zhang, Youming Northwest A&F Univ Coll Nat Resources & Environm Yangling 712100 Shaanxi Peoples R China

Leaf chlorophyll content (LCC) is one of the most important factors affecting photosynthetic capacity and nitrogen status, both of which influence crop harvest. However, the development of rapid and nondestructive methods for leaf chlorophyll estimation is a topic of much interest. Hence, this study explored the use of the machine learning approach to enhance the estimation of leaf chlorophyll from spectral reflectance data. The objective of this study was to evaluate four different approaches for estimating the LCC of apple tree leaves at five growth stages (the 1st, 2nd, 3rd, 4th and 5th growth stages): (1) univariate linear regression (ULR);(2) multivariate linear regression (MLR);(3) support vector regression (SVR);and (4) random forest (RF) regression. Samples were collected from the leaves on the eastern, western, southern and northern sides of apple trees five times (1st, 2nd, 3rd, 4th and 5th growth stages) over three consecutive years (2016-2018), and experiments were conducted in 10-20-year-old apple tree orchards. Correlation analysis results showed that LCC and ST, LCC and vegetation indices (VIs), and LCC and three edge parameters (TEP) had high correlations with the first-order differential spectrum (FODS) (0.86), leaf chlorophyll index (LCI) (0.87), and (SDr - SDb)/ (SDr + SDb) (0.88) at the 3rd, 3rd, and 4th growth stages, respectively. The prediction models of different growth stages were relatively good. The MLR and SVR models in the LCC assessment of different growth stages only reached the highest R-2 values of 0.79 and 0.82, and the lowest RMSEs were 2.27 and 2.02, respectively. However, the RF model evaluation was significantly better than above models. The R-2 value was greater than 0.94 and RMSE was less than 1.37 at different growth stages. The prediction accuracy of the 1st growth stage (R-2 = 0.96, RMSE = 0.95) was best with the RF model. This result could provide a theoretical basis for orchard management. In the future, more models based

关键词： leaf chlorophyll content hyperspectral remote sensing RF SVR

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Resveratrol elongates the lifespan and improves antioxidant activity in the silkworm Bombyx mori

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Journal of Pharmaceutical Analysis 2021年第3期11卷 374-382页

作者： Jiangbo Song Lian Liu Kaige Hao Shuang Mao Yongxi Tang Xiaoling Tong Fangyin Dai State Key Laboratory of Silkworm Genome Biology Key Laboratory for Sericulture Biology and Genetic BreedingMinistry of Agriculture and Rural AffairsCollege of BiotechnologySouthwest UniversityNo.2 Tiansheng RoadBeibei DistrictChongqing400715China

A number of research has shown that the plant polyphenol resveratrol,one of the most prominent small molecules,has beneficial protective effects in multiple organisms,including worms,flies,and *** understand the effects of resveratrol on lifespan,we evaluated its effects in the silkworm Bombyx *** this study,we found that lifespan was significantly prolonged in both female and male silkworms treated with *** larval weight was significantly increased from day 3 of the 5th larval instar(L5D3)to day 7 of the 5th larval instar(L5D7).However,the weight of the pupa,cocoon,and total cocoon was not significantly different in female silkworms with resveratrol treatment than that in ***,resveratrol significantly improved the thermotolerance of the silkworms,which enhanced their survival ***,antioxidant activity was increased by resveratrol in both female and male ***,an antioxidant-related signalling pathway,SIRT7-FoxO-GST,was activated in silkworms with resveratrol ***,these results help us to understand the molecular pathways underlying resveratrol induced pro-longevity effects and indicate that silkworm is a promising animal model for evaluating the effects of lifespan-extending drugs.

关键词： Resveratrol Bombyx mori Lifespan Antioxidant activity SIRT7-FoxO-GST pathway

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New rationale for the effect of multiple buoyancies and their influence on the propagation of respiratory pollutants

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PHYSICS OF FLUIDS 2024年第1期36卷 015116-015116页

作者： Deng, Xiaorui Gong, Guangcai He, Xizhi Wang, Yuxin Huang, Yuting Chen, Xiang Hunan Univ Coll Civil Engn Changsha 410082 Peoples R China

The effect of buoyancy on fluid flows is a significant consideration in problems relating to energy, the environment, and health. Here, we examine what we term a "multi-buoyancy effect" (MBE), or "fluid-bunching effect," which is a combination of the Archimedes number (Ar)-related buoyancy resulting from the temperature difference between a fluid flow and the ambient fluid and the Gc number (Gc)-related buoyancy resulting from the temperature difference between the upper and lower boundaries of the fluid domain. A new semi-analytical mathematical model of the jet trajectory is put forward by rational reconstruction. This reveals the physical mechanisms of fluid flows propagating in limited spaces under this MBE. Human respiratory experiments were conducted to show that the MBE can govern the transmission of infective airborne pollutants between people. Our findings provide a new perspective in the transmission of fluid flows and airborne pollutants in limited spaces. They are, thus, also of great interest for predicting the stratification of flows and circulation of the atmosphere and ocean.

关键词： Flow of fluids

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Comparative analysis of integument transcriptomes identifies genes that participate in marking pattern formation in three allelic mutants of silkworm, Bombyx mori

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FUNCTIONAL & INTEGRATIVE GENOMICS 2020年第2期20卷 223-235页

作者： Ding, Xin Liu, Junxia Tong, Xiaoling Wu, Songyuan Li, Chunlin Song, Jiangbo Hu, Hai Tan, Duan Dai, Fangyin Southwest Univ Minist Agr & Rural Affairs Key Lab Sericultural Biol & Genet Breeding Coll BiotechnolState Key Lab Silkworm Genome Bio Chongqing 400715 Peoples R China

The diversity markings and pigment patterns in insects are outcomes of adaptive evolution. The elucidation of the molecular mechanism underlying variations in pigment patterns may improve our understanding of the origin and evolution of these spectacular diverse phenotypes. Melanin, ommochrome, and pteridine are the three main types of insect pigments, and the genes that directly participate in pigment biosynthesis have been extensively studied. However, available information on gene interactions and the whole pigment regulatory network is limited. In this study, we performed integument transcriptome sequencing to analyze three larval marking allelic mutants, namely, multi lunar (L), L(C), and L-Ca, which have similar twin-spot markings on the dorsal side of multiple segments. Further analysis identified 336 differentially expressed genes (DEGs) between L and Dazao (wild type which exhibits normal markings), 68 DEGs between L(C)/+ and +(LC)/+(LC), and 188 DEGs between L-Ca/+ and +(LCa)/+(LCa). Gene Ontology (GO) analysis indicated a significant DEG enrichment of the functional terms catalytic activity, binding, metabolic process, and cellular process. Furthermore, three mutants share six common enriched KEGG pathways. We finally identified eight common DEGs among three pairwise comparisons, including Krueppel-like factor, TATA-binding protein, protein patched, UDP-glycosyltransferase, an unknown secreted protein, and three cuticular proteins. Microarray-based gene expression analysis revealed that the eight genes are upregulated during molting, which coincides with marking formation, and are significantly differentially expressed between marking and non-marking regions. The results suggest that the eight common genes are involved in the construction of the multiple twin-spot marking patterns in the three mutants.

关键词： Bombyx mori Allelic mutants Integument Transcriptome Pigment Marking pattern

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Effects of Drying and Rewetting Cycles on Carbon Dioxide Emissions and Soil Microbial Communities

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FORESTS 2022年第11期13卷 1916-1916页

作者： Zhang, Yun Li, Xiaohan Liu, Xinmei Cui, Yufei Zhang, Ye Zheng, Xiaoying Zhang, Weiwei Fan, Yue Zou, Junliang Beijing Acad Agr & Forestry Sci Inst Grassland Flowers & Ecol Beijing 100097 Peoples R China

Extreme rainfall and drought events attributed to climate change are anticipated to occur in the current century, resulting in frequent drying and rewetting cycles (DWCs) in soils, which will, in turn, influence soil properties and microorganisms. Sample plots of Sophora japonica, Pinus tabulaeformis, and Ginkgo biloba were selected, and undisturbed soil columns were collected. CK was the constant drying treatment;the precipitation intensities of R80, R40, and R20 were 80 mm, 40 mm, and 20 mm, respectively, and the total precipitation for the four treatments was 160 mm. Significant differences were observed in the cumulative CO2 emissions among the various DWC frequencies for the same woodland soils. A significant correlation was observed between the Birch effect and the DWC frequencies of the three woodland soils. A Pearson's correlation analysis revealed that background nutrient contents were the key factors influencing alpha diversity. In conclusion, DWCs generally increased CO2 fluxes, cumulative CO2 emissions, and the Birch effect in addition to decreasing the alpha diversity of soil microorganisms when compared to those in the constant drying treatment.

关键词： drying and rewetting soil microorganisms CO2 fluxes cumulative CO2 emissions woodland soils

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Low-voltage Injection-free Electroluminescence Device based on a Monolayer MoSe2/WSe2 Lateral Heterostructure

Low-voltage Injection-free Electroluminescence Device based ...

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2024 Conference on Lasers and Electro-Optics, CLEO 2024

作者： Zhong, Yutong Ma, Hanyuan Lv, Qian Li, Yongzhuo Feng, Jiabin Li, Chen Xu, Jialu Yu, Chenxin Lv, Ruitao Ning, Cun-Zheng Department of Electronic Engineering Tsinghua University Beijing100084 China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and Engineering Tsinghua University Beijing100084 China School of Materials Science and Engineering Nanyang Technological University Singapore639798 Singapore College of Integrated Circuits and Optoelectronic Chips Shenzhen Technology University Guangdong Shenzhen518118 China

We demonstrate an injection-free electroluminescence device fabricated with a CVD-grown monolayer MoSe2/WSe2 lateral heterostructure. The device is based on impact generation of excitons through an alternating voltage... 详细信息

ISBN: (纸本)9781957171395

关键词： Heterojunctions

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Enhanced Electromagnetic Shielding and Thermal Conductive Properties of Polyolefin Composites with a Ti3C2TX MXene/Graphene Framework Connected by a Hydrogen-Bonded Interface

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ACS NANO 2022年第6期16卷 9254-9266页

作者： Tan, Xue Liu, Te-Huan Zhou, Wenjiang Yuan, Qilong Ying, Junfeng Yan, Qingwei Lv, Le Chen, Lu Wang, Xiangze Du, Shiyu Wan, Yan-Jun Sun, Rong Nishimura, Kazuhito Yu, Jinhong Jiang, Nan Dai, Wen Lin, Cheng-Te Chinese Acad Sci Ningbo Inst Mat Technol & Engn NIMTE Key Lab Marine Mat & Related Technol Zhejiang Key Lab Marine Mat & Protect Technol Ningbo 315201 Peoples R China Univ Chinese Acad Sci Ctr Mat Sci & Optoelect Engn Beijing 100049 Peoples R China Huazhong Univ Sci & Technol Sch Energy & Power Engn Wuhan 430074 Peoples R China Chinese Acad Sci Ningbo Inst Mat Technol & Engn Engn Lab Adv Energy Mat Ningbo 315201 Zhejiang Peoples R China Chinese Acad Sci Shenzhen Inst Adv Technol Shenzhen 518055 Peoples R China Kogakuin Univ Adv Nanoproc Engn Lab Mech Engn Tokyo 1920015 Japan

The rapid increase of operation speed, transmission efficiency, and power density of miniaturized devices leads to a rising demand for electromagnetic interference (EMI) shielding and thermal management materials in the semiconductor industry. Therefore, it is essential to improve both the EMI shielding and thermal conductive properties of commonly used polyolefin components (such as polyethylene (PE)) in electronic systems. Currently, melt compounding is the most common method to fabricate polyolefin composites, but the difficulty of filler dispersion and high resistance at the filler/filler or filler/matrix interface limits their properties. Here, a fold fabrication strategy was proposed to prepare PE composites by incorporation of a well-aligned, seamless graphene framework premodified with MXene nanosheets into the matrix. We demonstrate that the physical properties of the composites can be further improved at the same filler loading by nanoscale interface engineering: the formation of hydrogen bonds at the graphene/MXene interface and the development of a seamlessly interconnected graphene framework. The obtained PE composites exhibit an EMI shielding property of similar to 61.0 dB and a thermal conductivity of 9.26 W m-1 K-1 at a low filler content (similar to 3 wt %, including similar to 0.4 wt % MXene). Moreover, other thermoplastic composites with the same results can also be produced based on our method. Our study provides an idea toward rational design of the filler interface to prepare high-performance polymer composites for use in microelectronics and microsystems.

关键词： CVD graphene Ti3C2TX MXene polyolefin composites electromagnetic interference shielding thermal conductivity

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Disrupted rich-club network organization and individualized identification of patients with major depressive disorder

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PROGRESS IN NEURO-PSYCHOPHARMACOLOGY & BIOLOGICAL PSYChiATRY 2021年 108卷 110074-110074页

作者： Liu, Xinyi He, Cancan Fan, Dandan Zhu, Yao Zang, Feifei Wang, Qing Zhang, Haisan Zhang, Zhijun Zhang, Hongxing Xie, Chunming Southeast Univ Affiliated ZhongDa Hosp Sch Med Dept Neurol Nanjing 210009 Jiangsu Peoples R China Xinxiang Med Univ Psychol Sch Xinxiang 453003 Henan Peoples R China Southeast Univ Neuropsychiat Inst Affiliated ZhongDa Hosp Nanjing 210009 Jiangsu Peoples R China Xinxiang Med Univ Henan Prov Mental Hosp Xinxiang Key Lab Multimodal Brain Imaging Xinxiang 45300 Henan Peoples R China Xinxiang Med Univ Henan Prov Mental Hosp Dept Psychiat Xinxiang 45300 Henan Peoples R China

Background: Altered structural and functional brain networks have been extensively studied in major depressive disorder (MDD) patients. However, whether the differential connectivity patterns in the rich-club organization, assessed from structural brain network analyses, and the associated connections of these regions are particularly susceptible to depression remain unclear. Methods: We acquired resting-state functional magnetic resonance imaging (R-fMRI) and diffusion tensor imaging (DTI) from 31 unmedicated MDD patients and 32 cognitively normal (CN) subjects and completed a series of neuropsychological tests. Rich-club organization, network properties, and coupling between structural and functional connectivity (SC-FC) were explored. Furthermore, whether these indices could potentially deliver effective clinical predictive value for MDD patients were examined. Results: The MDD patients showed disrupted structural rich-club organization and modularity, as well as a distinct correlation pattern between global efficiency and rich-club organization. Importantly, reduced SC-FC coupling, reflecting a decreased agreement in the integrity of the networks, was significantly associated with the strength of structural rich-club connections in the MDD patients. Furthermore, the disrupted structural richclub organization, which was primarily located in the default mode network (DMN) and executive control network (ECN), emerged as a valuable indicator to distinguish between MDD and CN. Conclusions: Findings of this study identified that the disrupted rich-club structural organization significantly influenced brain structural network modularity and integrity and could serve as a promising biological marker for the identification of MDD patients.

关键词： Brain structural connectome Major depressive disorder Network efficiency Rich club organization

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Low-voltage Injection-free Electroluminescence Device based on a Monolayer MoSe2/WSe2 Lateral Heterostructure

Low-voltage Injection-free Electroluminescence Device based ...

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CLEO: Science and Innovations in CLEO 2024, CLEO: S and I 2024 - Part of Conference on Lasers and Electro-Optics

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Record Efficiency of Infrared 2D Materials Light-Emitting Diode Based on a Type-I Mote2/WSe2 Heterostructure

Record Efficiency of Infrared 2D Materials Light-Emitting Di...

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2024 Conference on Lasers and Electro-Optics, CLEO 2024

作者： Zhong, Yutong Li, Yongzhuo Feng, Jiabin Li, Chen Xu, Jialu Yu, Chenxin Ning, Cun-Zheng Department of Electronic Engineering Tsinghua University Beijing100084 China College of Integrated Circuits and Optoelectronic Chips Shenzhen Technology University Guangdong Shenzhen518118 China

We demonstrate an efficient infrared light-emitting diode based on a type-I Mote2/WSe2 heterostructure with a record EQE of 1% at room temperature, where multilayer WSe2 boosts carrier transport while monolayer Mote2 ... 详细信息

ISBN: (纸本)9781957171395

关键词： Carrier transport

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