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Using digital cameras for comparative phenological monitoring in an evergreen broad-leaved forest and a seasonal rain forest

Junbin Zhao, Yiping Zhang, Zhenghong Tan, Qinghai Song, Naishen Liang, Lei Yu, Junfu Zhao
2012 Ecological Informatics  
Digital cameras have been used in phenological observations for their high accuracy and low labor cost. Most studies successfully use greenness indices derived from digital images for timing the events related to leaf development. However, when timing the leaf senescence events, wide discrepancies between actual and estimated dates are common. In this study, images of three species (two from an evergreen broad-leaved forest and one from a seasonal rain forest) were used to estimate three
more » ... gical events of leaf development and senescence. Other than the greenness index, a redness index was also employed. Different annual patterns in color indices developed among the species. The redness index was more accurate when estimating leaf senescence, while the greenness index was more accurate for estimating leaf development events in Acer heptalobum and Machilus bombycina. The absolute differences in estimations of phenological events ranged from − 3 to 1 day, which is more accurate than estimates based on the greenness index only (− 2 to 27 days). With the introduction of the redness index, this technique has been much improved and is possible to be applied to more species. Furthermore, variations of color indices during periods of phenological events were highly related to the climatic factors with a time lag of around 10 days. Because of the ease of use and efficiency (i.e., automatic daily data output), digital cameras are expected to be used in ecosystem process modeling, networks of phenology assessment and validation of the remote sensing results from satellites.
doi:10.1016/j.ecoinf.2012.03.001 fatcat:lvr3oqrw6rbebijrog24l7xlqy

The effect of drought stress on self-organisation in a seasonal tropical rainforest

Qinghai Song, Hua Lin, Yiping Zhang, Zhenghong Tan, Junfu Zhao, Junbin Zhao, Xiang Zhang, Wenjun Zhou, Lei Yu, Lianyan Yang, Guirui Yu, Xiaomin Sun
2013 Ecological Modelling  
From late 2009 to 2010, southwestern China experienced a severe drought. We evaluated the selforganisation of a seasonal tropical rainforest in response to drought stress. The forest had the least self-organization in 2010, and during the dry season (March-April) of 2010, the forest was least able to capture exergy (Rn/DR). The rate of long wave radiation (I/DR) loss was highest in 2010. The thermal response number of canopy temperature (TRNc) and Rn/DR showed similar trends and decreased from
more » ... he rainy season to the dry seasons in each of the three years.
doi:10.1016/j.ecolmodel.2013.06.010 fatcat:eyr7bm4kyjfcpnt7b6cakrr4xy

High temperature causes negative whole-plant carbon balance under mild drought

Junbin Zhao, Henrik Hartmann, Susan Trumbore, Waldemar Ziegler, Yiping Zhang
2013 New Phytologist  
Theoretically, progressive drought can force trees into negative carbon (C) balance by reducing stomatal conductance to prevent water loss, which also decreases C assimilation. At higher temperatures, negative C balance should be initiated at higher soil moisture because of increased respiratory demand and earlier stomatal closure. Few data are available on how these theoretical relationships integrate over the whole plant. We exposed Thuja occidentalis to progressive drought under three
more » ... ture conditions (15, 25, and 35°C), and measured C and water fluxes using a whole-tree chamber design. High transpiration rates at higher temperatures led to a rapid decline in soil moisture. During the progressive drought, soil moisture-driven changes in photosynthesis had a greater impact on the whole-plant C balance than respiration. The soil moisture content at which wholeplant C balance became negative increased with temperature, mainly as a result of higher respiration rates and an earlier onset of stomatal closure under a warmer condition. Our results suggest that the effect of drought on whole-plant C balance is highly temperature-dependent. High temperature causes a negative C balance even under mild drought and may increase the risk of C starvation.
doi:10.1111/nph.12400 pmid:23822669 fatcat:m2dea3b6ffhw3dpec2v2sopghy

Susceptibility of tree shrew to SARS-CoV-2 infection [article]

Yuan Zhao, Junbin Wang, Dexuan Kuang, Jingwen Xu, Mengli Yang, Chunxia Ma, Siwen Zhao, Jingmei Li, Haiting Long, Kaiyun Ding, Jiahong Gao, Jiansheng Liu (+10 others)
2020 bioRxiv   pre-print
Therefore, tree shrew is not a suitable experimental , Yuan Zhao, Junbin Wang, Dexuan Kuang, Wenhai Yu, Yun Yang, Haixuan Wang, Haiyan Li and Daoju Wu performed animal-related experiments.  ...  Hongqi Liu, Shuaiyao Lu, Yuan Zhao designed the experiments, interpreted data and wrote the manuscript.  ... 
doi:10.1101/2020.04.30.029736 fatcat:zmeneho4w5hflhgpwx53n2ltgu

Automatic Classification Framework of Tongue Feature Based on Convolutional Neural Networks

Jiawei Li, Zhidong Zhang, Xiaolong Zhu, Yunlong Zhao, Yuhang Ma, Junbin Zang, Bo Li, Xiyuan Cao, Chenyang Xue
2022 Micromachines  
Tongue diagnosis is an important part of the diagnostic process in traditional Chinese medicine (TCM). It primarily relies on the expertise and experience of TCM practitioners in identifying tongue features, which are subjective and unstable. We proposed a tongue feature classification framework based on convolutional neural networks to reduce the differences in diagnoses among TCM practitioners. Initially, we used our self-designed instrument to capture 482 tongue photos and created 11 data
more » ... s based on different features. Then, the tongue segmentation task was completed using an upgraded facial landmark detection method and UNET. Finally, we used ResNet34 as the backbone to extract features from the tongue photos and classify them. Experimental results show that our framework has excellent results with an overall accuracy of over 86 percent and is particularly sensitive to the corresponding feature regions, and thus it could assist TCM practitioners in making more accurate diagnoses.
doi:10.3390/mi13040501 pmid:35457806 pmcid:PMC9025353 fatcat:yjxh7g3k3faq7iobc5oyc6o2gq

FluxCalR: a R package for calculating CO~2~ and CH~4~ fluxes from static chambers

Junbin Zhao
2019 Journal of Open Source Software  
The original functions in the package have been used for flux calculations in the previous publications (Zhao et al., 2016 (Zhao et al., , 2017 and in other ongoing research projects performed in the  ...  The R 2 of the regression is usually taken to determine the quality of a flux measurement and a regression with low R 2 is usually discarded (Zhao, Peichl, & Nilsson, 2016 , 2017 .  ... 
doi:10.21105/joss.01751 fatcat:t2gvysuyhzfg7gpzio2etexi2u

AIM1-dependent high basal SA accumulation modulates stomatal aperture in rice [article]

Lei Xu, Hongyu Zhao, Junbin Wang, Xuming Wang, Xianqing Jia, Zhuang Xu, Ruili Li, Kun Jiang, Zhixiang Chen, Jie Luo, Xiaodong Xie, Keke Yi
2022 bioRxiv   pre-print
The basal levels of salicylic acid (SA), an important plant hormone, vary dramatically among plant species. In the shoot, for example, the monocot plant rice contains almost 100 times higher SA levels than the dicot model plant Arabidopsis. Despite its high basal levels, neither the biosynthetic pathway nor the biological functions of SA is well understood in rice. Here, we report that the synthesis of basal SA in rice shoot is not altered in the mutant for the ISOCHORISMATE SYNTHASE (ICS)
more » ... but drastically reduced in the mutant for OsAIM1, which encodes a beta-oxidation enzyme in the phenylalanine ammonia-lyase (PAL) pathway. Analogous to its role in thermogenesis, compromised SA accumulation in the Osaim1 mutant led to a lower shoot temperature than wild-type plants. However, this shoot temperature defect was resulted from increased transpiration due to elevated steady-state stomatal aperture in the mutant. Furthermore, the high basal shoot SA level is required for sustained expression of WRKY45 to modulate the steady-state stomatal aperture and shoot temperature in rice. Taken together, these results provide the direct genetic evidence for the critical role of the PAL pathway in the biosynthesis of high levels of basal SA, which play an important role in the regulation of steady-state stomatal aperture to promote fitness under both normal and stress conditions.
doi:10.1101/2022.06.23.497111 fatcat:lysb5wsv7jd2vj32rioluzh3wu

Gap-filling continuously-measured soil respiration data: A highlight of time-series-based methods

Junbin Zhao, Holger Lange, Helge Meissner
2020 Agricultural and Forest Meteorology  
., 2006; Zhao et al., 2016) .  ...  The sizes of this sampling window are usually arbitrarily chosen, ranging from one halfmonth to a full year (e.g., Kunwor et al., 2017; Moffat et al., 2007; Zhao and Huang, 2015) .  ... 
doi:10.1016/j.agrformet.2020.107912 fatcat:qntbdatca5dwjgkmdhzmjeqige

Equivalence between belief propagation instability and transition to replica symmetry breaking in perceptron learning systems

Yang Zhao, Junbin Qiu, Mingshan Xie, Haiping Huang
2022 Physical Review Research  
The binary perceptron is a fundamental model of supervised learning for nonconvex optimization, which is a root of the popular deep learning. The binary perceptron is able to achieve a classification of random high-dimensional data based on the marginal probabilities of binary synapses. The relationship between the belief propagation instability and the equilibrium analysis of the model remains elusive. Here, we establish the relationship by showing that the instability condition around the
more » ... ef propagation fixed point is identical to the instability for breaking the replica symmetric saddle-point solution of the free-energy function. Therefore our analysis will hopefully provide insight towards other learning systems in bridging the gap between nonconvex learning dynamics and statistical mechanics properties of more complex neural networks.
doi:10.1103/physrevresearch.4.023023 fatcat:q32cspylwbdsrmhipcwgbwyfja

Freshwater wetland plants respond nonlinearly to inundation over a sustained period

Junbin Zhao, Sparkle L Malone, Christina L Staudhammer, Gregory Starr, Henrik Hartmann, Steven F Oberbauer
2021 American Journal of Botany  
In a field study, we previously found that inundation caused greater stress on photosynthesis in muhly grass than in sawgrass (Zhao et al., 2018) .  ...  content (Zhao et al., 2018) are also reduced, indicating that nonstomatal processes (e.g., carboxylation, electron transport) also limit photosynthesis under inundation stress.  ... 
doi:10.1002/ajb2.1746 pmid:34617586 fatcat:tmesrppbu5fuvfebidalqnpg6e

Molecular Mechanism and Genetic Determinants of Buprofezin Degradation

Xueting Chen, Junbin Ji, Leizhen Zhao, Jiguo Qiu, Chen Dai, Weiwu Wang, Jian He, Jiandong Jiang, Qing Hong, Xin Yan, M. Julia Pettinari
2017 Applied and Environmental Microbiology  
Buprofezin is a widely used insect growth regulator whose residue has been frequently detected in the environment, posing a threat to aquatic organisms and nontarget insects. Microorganisms play an important role in the degradation of buprofezin in the natural environment. However, the relevant catabolic pathway has not been fully characterized, and the molecular mechanism of catabolism is still completely unknown. Rhodococcus qingshengii YL-1 can utilize buprofezin as a sole source of carbon
more » ... d energy for growth. In this study, the upstream catabolic pathway in strain YL-1 was identified using tandem mass spectrometry. Buprofezin is composed of a benzene ring and a heterocyclic ring. The degradation is initiated by the dihydroxylation of the benzene ring and continues via dehydrogenation, aromatic ring cleavage, breaking of an amide bond, and the release of the heterocyclic ring 2- tert -butylimino-3-isopropyl-1,3,5-thiadiazinan-4-one (2-BI). A buprofezin degradation-deficient mutant strain YL-0 was isolated. A comparative genomic analysis combined with gene deletion and complementation experiments revealed that the gene cluster bfzBA3A4A1A2C is responsible for the upstream catabolic pathway of buprofezin. The bfzA3A4A1A2 cluster encodes a novel Rieske nonheme iron oxygenase (RHO) system that is responsible for the dihydroxylation of buprofezin at the benzene ring; bfzB is involved in dehydrogenation, and bfzC is in charge of benzene ring cleavage. Furthermore, the products of bfzBA3A4A1A2C can also catalyze dihydroxylation, dehydrogenation, and aromatic ring cleavage of biphenyl, flavanone, flavone, and bifenthrin. In addition, a transcriptional study revealed that bfzBA3A4A1A2C is organized in one transcriptional unit that is constitutively expressed in strain YL-1. IMPORTANCE There is an increasing concern about the residue and environmental fate of buprofezin. Microbial metabolism is an important mechanism responsible for the buprofezin degradation in the natural environment. However, the molecular mechanism and genetic determinants of microbial degradation of buprofezin have not been well identified. This work revealed that gene cluster bfzBA3A4A1A2C is responsible for the upstream catabolic pathway of buprofezin in Rhodococcus qingshengii YL-1. The products of bfzBA3A4A1A2C could also degrade bifenthrin, a widely used pyrethroid insecticide. These findings enhance our understanding of the microbial degradation mechanism of buprofezin and benefit the application of strain YL-1 and bfzBA3A4A1A2C in the bioremediation of buprofezin contamination.
doi:10.1128/aem.00868-17 pmid:28710269 pmcid:PMC5583499 fatcat:cuismqs3nnfn5e44dbcnu3at24

Susceptibility of tree shrew to SARS-CoV-2 infection

Yuan Zhao, Junbin Wang, Dexuan Kuang, Jingwen Xu, Mengli Yang, Chunxia Ma, Siwen Zhao, Jingmei Li, Haiting Long, Kaiyun Ding, Jiahong Gao, Jiansheng Liu (+10 others)
2020 Scientific Reports  
Since severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) became a pandemic event in the world, it has not only caused huge economic losses, but also a serious threat to global public health. Many scientific questions about SARS-CoV-2 and Coronavirus disease (COVID-19) were raised and urgently need to be answered, including the susceptibility of animals to SARS-CoV-2 infection. Here we tested whether tree shrew, an emerging experimental animal domesticated from wild animal, is
more » ... le to SARS-CoV-2 infection. No clinical signs were observed in SARS-CoV-2 inoculated tree shrews during this experiment except the increasing body temperature particularly in female animals. Low levels of virus shedding and replication in tissues occurred in all three age groups. Notably, young tree shrews (6 months to 12 months) showed virus shedding at the earlier stage of infection than adult (2 years to 4 years) and old (5 years to 7 years) animals that had longer duration of virus shedding comparatively. Histopathological examine revealed that pulmonary abnormalities were the main changes but mild although slight lesions were also observed in other tissues. In summary, tree shrew is less susceptible to SARS-CoV-2 infection compared with the reported animal models and may not be a suitable animal for COVID-19 related researches. However, tree shrew may be a potential intermediate host of SARS-CoV-2 as an asymptomatic carrier.
doi:10.1038/s41598-020-72563-w pmid:32994418 pmcid:PMC7525503 fatcat:icc7njgkynfcjjgudoydgvfshe

The Metabolic Signature of AML Cells Treated With Homoharringtonine

Yulong Zhang, Na Li, Zhiguang Chang, Huabin Wang, Hanzhong Pei, Dengyang Zhang, Qi Zhang, Junbin Huang, Yao Guo, Yuming Zhao, Yihang Pan, Chun Chen (+1 others)
2022 Frontiers in Oncology  
Acute myeloid leukemia (AML) is a hematologic malignancy. The overall prognosis is poor and therapeutic strategies still need to be improved. Studies have found that abnormalities in metabolisms promote the survival of AML cells. In recent years, an increasing number of studies have reported the effectiveness of a protein synthesis inhibitor, homoharringtonine (HHT), for the treatment of AML. In this study, we demonstrated that HHT effectively inhibited AML cells, especially MV4-11, a cell line
more » ... representing human AML carrying the poor prognostic marker FLT3-ITD. We analyzed the transcriptome of MV4-11 cells treated with HHT, and identified the affected metabolic pathways including the choline metabolism process. In addition, we generated a line of MV4-11 cells that were resistant to HHT. The transcriptome analysis showed that the resistant mechanism was closely related to the ether lipid metabolism pathway. The key genes involved in these processes were AL162417.1, PLA2G2D, and LPCAT2 by multiple intergroup comparison and Venn analysis. In conclusion, we found that the treatment of HHT significantly changed metabolic signatures of AML cells, which may contribute to the precise clinical use of HHT and the development of novel strategies to treat HHT-resistant AML.
doi:10.3389/fonc.2022.931527 pmid:35774129 pmcid:PMC9237253 fatcat:siz4znveyfgupncpswjh2loa3m

Synergistic Enhancement Properties of a Flexible Integrated PAN/PVDF Piezoelectric Sensor for Human Posture Recognition

Jiliang Mu, Shuai Xian, Junbin Yu, Juanhong Zhao, Jinsha Song, Zhengyang Li, Xiaojuan Hou, Xiujian Chou, Jian He
2022 Nanomaterials  
The flexible pressure sensor has attracted much attention due to its wearable and conformal advantage. All the same, enhancing its electrical and structural properties is still a huge challenge. Herein, a flexible integrated pressure sensor (FIPS) composed of a solid silicone rubber matrix, composited with piezoelectric powers of polyacrylonitrile/Polyvinylidene fluoride (PAN/PVDF) and conductive silver-coated glass microspheres is first proposed. Specifically, the mass ratio of the PAN/PVDF
more » ... the rubber is up to 4:5 after mechanical mixing. The output voltage of the sensor with composite PAN/PVDF reaches 49 V, which is 2.57 and 3.06 times that with the single components, PAN and PVDF, respectively. In the range from 0 to 800 kPa, its linearity of voltage and current are all close to 0.986. Meanwhile, the sensor retains high voltage and current sensitivities of 42 mV/kPa and 0.174 nA/kPa, respectively. Furthermore, the minimum response time is 43 ms at a frequency range of 1–2.5 Hz in different postures, and the stability is verified over 10,000 cycles. In practical measurements, the designed FIPS showed excellent recognition abilities for various gaits and different bending degrees of fingers. This work provides a novel strategy to improve the flexible pressure sensor, and demonstrates an attractive potential in terms of human health and motion monitoring.
doi:10.3390/nano12071155 pmid:35407273 pmcid:PMC9000213 fatcat:pe3dofvfr5d4jambba5n3siqpq

Hematological and biochemical parameters for Chinese rhesus macaque

Wenhai Yu, Xianhui Hao, Fengmei Yang, Jin Ma, Yuan Zhao, Yanyan Li, Junbin Wang, Hongjie Xu, Lixiong Chen, Quan Liu, Suqin Duan, Yaping Yang (+3 others)
2019 PLoS ONE  
Rhesus macaque is an important animal model in biomedical research, especially human disease, developmental, translational, and pre-clinical research. Blood physiological and biochemical parameters are important markers for physiology, pathology, and toxicology research. However, these parameters have not been systematically reported for Chinese rhesus macaques. To characterize the reference for these parameters, this study collected 1805 Chinese rhesus macaques living in Southwestern China. A
more » ... otal of 24 blood physiological indexes and 27 biochemical parameters were determined. Sex and age were found to affect these parameters. In conclusion, a comprehensive and systematic reference of hematological and biochemical parameters for Chinese rhesus macaque was established in this work on the basis of a large cohort. Such reference will benefit biomedical research employing rhesus macaques as animal models.
doi:10.1371/journal.pone.0222338 pmid:31527891 pmcid:PMC6748566 fatcat:3hh3qhvyhjgexmlfdwnkurghtm
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