检索结果-南通市图书馆

International Journal of Digital Earth 2022年第1期15卷 832-852页

作者： Katsuto Shimizu Tetsuji Ota Nariaki Onda Nobuya Mizoue Department of Forest management Forestry and Forest Products Research InstituteIbarakiJapan Faculty of Agriculture Kyushu UniversityFukuokaJapan Tohoku research Center Forestry and Forest Products Research InstituteIwateJapan

Mapping of deforestation,forest degradation,and recovery is essential to characterize country-level forest change and formulate mitigation *** studies have mainly used a simple forest/non-forest classification after forest disturbance to identify deforestation and forest ***,a more flexible approach that is applicable to different forest conditions is *** this study,we examined an approach for mapping deforestation,forest degradation,and recovery using disturbance types and tree canopy cover estimates from annual Landsat time-series data from 1988 to 2020 across *** developed models to estimate both disturbance types and tree canopy cover based on a random forest algorithm using predictor variables derived from a trajectory-based temporal segmentation *** estimated disturbance types and canopy cover in each year were then used in a rule-based classification of deforestation,forest degradation,and *** producer’s and user’s accuracies ranged from 59.1%to 72.9%and 60.8%to 91.6%,respectively,for the forest change classes of mapping deforestation,forest degradation,and *** approach developed here can be adjusted for different definitions of deforestation,forest degradation,and recovery according to research objectives and thus has the potential to be applied to other study areas.

关键词： Deforestation degradation time series Google Earth Engine tropical forest

Distribution of chlorpyrifos in rice paddy environment and its potential dietary risk

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2015年第9期27卷 101-107页

作者： Yan Fu Feifei Liu Chenglin Zhao Ying Zhao Yihua Liu Guonian Zhu institute of Pesticide and Environmental Toxicology Zhejiang University research institute of Subtropical forestry Chinese Academy of Forestry

Chlorpyrifos is one of the most extensively used insecticides in China. The distribution and residues of chlorpyrifos in a paddy environment were characterized under field and laboratory conditions. The half-lives of chlorpyrifos in the two conditions were 0.9–3.8 days（field） and 2.8–10.3 days（laboratory）, respectively. The initial distribution of chlorpyrifos followed the increasing order of water 〈 straw 〈 soil, and soil was characterized as the major absorber. The ultimate residues in rice grain were below the maximum residue limit（MRL） with a harvest interval of 14 days. The chronic exposure for chlorpyrifos was rather low compared to the acceptable daily intake（ADI = 0.01 mg/kg bw） due to rice consumption. The chronic exposure risk from chlorpyrifos in rice grain was 5.90% and 1.30% ADI from field and laboratory results respectively. Concerning the acute dietary exposure,intake estimated for the highest chlorpyrifos level did not exceed the acute reference dose（ARf D = 0.1 mg/kg bw）. The estimated short-term intakes（ESTIs） were 0.78% and 0.25% of the ARf D for chlorpyrifos. The results showed that the use of chlorpyrifos in rice paddies was fairly safe for consumption of rice grain by consumers.

关键词： Chlorpyrifos Distribution Paddy environment Dietary risk assessment

Peficitinib suppresses diffuse-type tenosynovial giant cell tumor by targeting TYK2 and JAK/STAT signaling

在线全文

学校读者我要写书评

暂无评论

Science China Life Sciences 2025年

作者： Shan Lu Chenxi Cao Wenjia Zhang Jiayi Li Jingli Yang Zisheng Huang Zhijun Wu Baitao Liu Hongjie Huang Haijun Wang Yongjian Wang Dingge Liu Zhihua Zhang Kaiping Liu Gang Yang Xi Gong Hui Dai Yingjia Li Erdan Dong Xin Zhang Yan Zhang Haihe Laboratory of Cell Ecosystem institute of Cardiovascular Diseases The First Affiliated Hospital of Dalian Medical University institute of Cardiovascular Sciences School of Basic Medical Sciences Peking University Health Science Center Department of Cardiology and Institute of Vascular Medicine Peking University Third HospitalState Key Laboratory of Vascular Homeostasis and Remodeling Peking University Department of Sports Medicine Peking University Third Hospital Institute of Sports Medicine of Peking University Beijing Key Laboratory of Sports Injuries Engineering research Center of Sports Trauma Treatment Technology and Devices Ministry of Education State Key Laboratory of Membrane Biology Institute of Molecular Medicine College of Future Technology Peking University Peking University Health Science Centre Peking University Department of Immunology School of Basic Medical Sciences NHC Key Laboratory of Medical Immunology Peking University research Center for Cardiopulmonary Rehabilitation University of Health and Rehabilitation Sciences Qingdao Hospital (Qingdao Municipal Hospital) School of Health and Life Sciences University of Health and Rehabilitation Sciences research Unit of Medical Science research management/Basic and Clinical research of Metabolic Cardiovascular Diseases Chinese Academy of Medical Sciences

Diffuse-type tenosynovial giant cell tumor(dTGCT) is a destructive but rare benign proliferative synovial neoplasm. Although surgery is currently the main treatment modality for dTGCT, the recurrence risk is up to 50%. Therefore, there is a great need for effective drugs against dTGCT with minor side effects. The Janus kinase(JAK)/signal transducer and activator of transcription(STAT) signaling plays a central role in rheumatoid arthritis(RA), a disease with similar characteristics as dTGCT, but its function in dTGCT remains *** fibroblast-like synoviocytes(FLS) and macrophages were isolated from 10 synovial tissue samples from dTGCT patients for the screening and validation of the five clinically approved JAK inhibitors to treat RA against dTGCT. Cell viability, cell death, inflammation and the activity of the JAK family members of cultured dTGCT FLS(both 2-D and 3-D) and macrophages were investigated for the efficacy of the JAK inhibitors. Here, we found that similar to RA, JAK/STAT signaling was markedly activated in the dTGCT synovium. Of the 5 JAK inhibitors, peficitinib was shown to have the most potency in addressing some of the pathological responses of dTGCT FLS and *** potency of peficitinib was much higher than pexidartinib, which is the only FDA-approved drug for dTGCT. Mechanistically, peficitinib inhibited tyrosine kinase 2(TYK2), a JAK family member necessary for the pathological progression of dTGCT FLS and macrophages. In summary, we not only revealed JAK/STAT(especially TYK2) signaling as the major mechanism underlying dTGCT, but also identified peficitinib as a promising drug against dTGCT.

关键词：

Crown Fuel Characteristics and Carbon Emission from Japanese Red Pine Stands Burned by Crown Fire in Mt. Palgong, South Korea

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Mountain Science 2012年第5期9卷 656-664页

作者： Byungdoo LEE Myoung Soo WON Yohan LEE Myung Bo LEE Division of Forest Disaster management Korea Forest Research Institute College of forestry Oregon State University

Carbon emissions from forest fires are considered an important factor of ecosystem carbon balance and global climate change. Carbon emissions from Japanese red pine stands （Pinus densiflora S. et Z.） burned by crown fire were estimated at Mt. Palgong in Daegu Metropolitan City, and crown fuel characteristics, including crown bulk density, crown base height, and fuel moisture content of Japanese red pine, were analyzed. Total biomass combusted was calculated by subtracting the biomass of burned stands from that of unburned stands exhibiting similar stand structures and site environments. Ten trees in the unburned area and five trees in the burned area were cut by using direct harvesting techniques to estimate crown layer biomass. All biomass sampled was oven-dried and weighed. The dry weight ratios of stems, branches, and needles were 7o%, 21%, and 9%, respectively. The available fuel load susceptible to combustion during the crown fire spread was equivalent to 55% of the crown layer biomass. The crown bulk density was 0.24 kg/m3 on average. The estimated amount of CO2 was 23,454 kg CO2/ha for the crown layer. These results will be useful for calculating the amount of CO2 emitted from forest fires and for developing a forest carbon model in P. densiflora forests.

关键词： Biomass burning Crown fire Fuelcharacteristics Bulk density Pinus densiflora

Sap flow characteristics of three afforestation species during the wet and dry seasons in a dry-hot valley in Southwest China

在线全文

学校读者我要写书评

暂无评论

Journal of forestry research 2017年第1期28卷 51-62页

作者： Xiaofei Wang Jianfeng Liu Yongyu Sun Kun Li Chunhua Zhang research institute of Resources Insects Chinese Academy of Forestry Key Laboratory of Tree Breeding and Cultivation of State forestry Administration Research Institute of ForestryChinese Academy of Forestry

Assessing and using tree species （exotic or native） with superior tolerance to environmental stresses （such as drought and high temperature） play an important role in afforestation practices. In the present study, stem sap flow characteristics and responses to ambient meteo- rological factors of three tree species, Albizzia kalkora （native）, Azadirachta indica （exotic）, and Acacia auriculaeformis （exotic）, in a dry-hot valley （Yuanmou, Yunnan Province, China） were investigated using thermal dissipation probes. The diurnal dynamics of sap flow in three studied species displayed an obvious circadian rhythm during the wet and dry seasons, with the exception of A. indica during the dry season. The sap flow velocity （SFV） in A. kalkora and A. auriculaeformis was significantly positively correlated with photosynthetically active radiation （PAR）, air temperature, vapour pressure deficit （VPD） and wind speed, but negatively correlated with atmospheric relative humidity over the two seasons. The cross-corre- lation analysis also revealed that the SFV of the three species was significantly correlated with PAR and VPD （P 〈 0.001）. Additionally, stem sap flow lagged behind PAR but ahead of VPD, and the diurnal sap flow was more dependent on PAR than on VPD. However, we found that the dominant climatic factor influencing the stem sap flow differed between daytime and nighttime. PAR was more influential than other meteorological factors during the daytime, while VPD or other factors were more influential overnight. When the nighttime refilling ability of the three tree species was compared, our results suggest that A. indica has higher drought resistance and better for afforestation of the studied region.

关键词： Sap flow Thermal dissipation probes Meteorological factors Refill Dry-hot valley

Morphometric study confirms the presence of only Vatica mangachapoi on Hainan Island, China

在线全文

学校读者我要写书评

暂无评论

Journal of forestry research 2018年第3期29卷 636-643页

作者： Junjie Guo Shuaibin Shang Jie Zeng research institute of Tropical forestry CAF

To date only one species of the genus Vatica Linn.(Dipterocarpaceae) has been identified, and a subspecies and three varieties have been reported on Hainan Island, China. However, it remained controversial whether the species was Vatica mangachapoi or a new species Vatica hainanensis, and whether the subspecies or varieties are taxonomically valid. We evaluated here morphometric variations of 133 trees collected from nine populations and herbarium specimens of Vatica spp. using 16 traits of leaf and fruit. Among these, leaf traits varied more within and among populations than did fruit traits. Four traits of ratios were more stable than directly-measured traits within and among populations. The ranges of lamina length, lamina width and height of maximum lamina width point were the greatest among the 16 traits, while number of lateral veins varied least among the 12 directly-measured traits. Measurements from all 9 populations overlapped for each morphological trait, and variation of each trait was continuous among both individuals and populations. The range of variation did not distinguish any specimen from V mangachapoi as described in the flora of Southeast Asia By cluster analysis, individuals of each population as wel as specimens of each variety formed no distinct clusters The published varieties thus were characterized by no distinguishing variations in comparison with the nine sampled populations. In conclusion, the new species V hainanensis as well as the subspecies and varieties were not supported by our comparisons, and only V. man gachapoi without any subspecies or varieties occurs on Hainan Island, China.

关键词： Vatica Linn. Vatica mangachapoi Morphological variability Cluster analysis Hainan Island

High-quality total RNA extraction from Magnolia sieboldii *** seeds:a comparative evaluation

在线全文

学校读者我要写书评

暂无评论

Journal of forestry research 2019年第1期30卷 371-379页

作者： Jun Wei Xiaolin Zhang Zhe Hou Xiujun Lu Department of forestry Shenyang Agricultural University research institute of forestry Chinese Academy of Forestry

Magnolia sieboldii K. Koch seed is characterized with having deep dormancy. The inner molecular regulation mechanism has not been investigated because of the absence of a protocol for total RNA(ribonucleic acid)extraction. The extraction of high-quality RNA is important and can be a limiting factor in plant molecular biology experiments. Sufficient high-quality total RNA is required to elucidate the molecular regulation mechanism of germination. However, M. sieboldii seeds with large amounts of secondary metabolites also contain recalcitrant tissues for RNA isolation. We found two simple and low-cost RNA extraction methods for M. sieboldii seeds by evaluating and selecting eight types of methods and further optimizing these methods. The two methods were not only suitable for extracting M. sieboldii seed RNA but also applicable to RNAs from several other tissues. Total RNA extracted through these approaches was applicable for general molecular biology experiments such as qRT-PCR(quantitative real-time polymerase chain reactions). The protocols also meet the strict harsh requirements for transcriptome sequencing and small RNA sequencing. This study provides a powerful approach for future studies at the transcription level.

关键词： Seed dormancy RNA isolation qRT-PCR Small RNA Magnolia sieboldii

Localizing base stations with measured data:a concatenated image-based deep learning approach

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2025年

作者： Yang CHEN Ziyuan LIU Feng JIANG Hong SHEN Wei XU Mengyu LI Ritao CHENG National Mobile Communications research Laboratory Southeast University China Mobile Group Design institute Co. Ltd.

Localization has become an indispensable function of modern cellular communication systems[1]. In a cloud radio access network （C-RAN）, the remote radio head （RRH） is the actual signal transmitter, whose location ...

关键词：

Radial profile of sap flow velocity in mature Xinjiang poplar(Populus alba L. var. pyramidalis) in Northwest China

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Arid Land 2014年第5期6卷 612-627页

作者： HongZhong DANG TianShan ZHA JinSong ZHANG Wei LI ShiZeng LIU institute of Desertification Studies Chinese Academy of Forestry School of Soil and Water Conservation Beijing Forestry University research institute of forestry Chinese Academy of Forestry Gansu Desert Control research institute

Estimation of the transpiration rate for a tree is generally based on sap flow measurements within the hydro-active stem xylem. In this study, radial variation of sap flow velocity（Js） was investigated at five depths of the xylem（1, 2, 3, 5 and 8 cm under the cambium） in three mature Xinjiang poplar（Populus alba L. var. pyramidalis） trees grown at the Gansu Minqin National Studies Station for Desert Steppe Ecosystem from May to October 2011. Thermal dissipation probes of various lengths manufactured according to the Granier＇s design were installed into each tree for simultaneous observation of the radial patterns of Js through the xylem. The radial patterns were found to fit the four-parameter GaussAmp equation. The peak Js was about 27.02±0.95 kg/（dm2？d） at approximately 3 to 5 cm deep from the cambium of the three trees,and the lowest Js appeared at 1 cm deep in most of the time. Approximately 50% of the total sap flow in Xinjiang poplar occurred within one-third of the xylem from its outer radius, whereas 90% of the total sap flow occurred within two-fifth of the xylem. In addition, the innermost point of the xylem（at 8-cm depth）, which appeared as the penultimate sap flow in most cases during the study period, was hydro-active with Js,8 of 7.55±3.83 kg/（dm2？d）. The radial pattern of Js was found to be steeper in midday than in other time of the day, and steeper diurnal fluctuations were recorded in June, July and August（the mid-growing season）. Maximum differences between the lowest Js（Js,1 or Js,8） and the highest Js（Js,3 or Js,5） from May through October were 12.41, 17.35, 16.30, 18.52, 12.60 and 16.04 g/（cm2？h）, respectively. The time-dependent changes of Js along the radial profile（except at 1-cm depth） were strongly related to the reference evapotranspiration（ET0）. Due to significant radial variability of Js, the mean daily sap flow at the whole-tree level could be over-estimated by up to 29.69% when only a single probe at depth of 2 cm was used. However, t

关键词： sap flow radial pattern Populus alba L.var.pyramidalis reference evapotranspiration(ET0) Granier method

Simulating the heartwood formation process of Erythrophleum fordii in South China

在线全文

学校读者我要写书评

暂无评论

Journal of forestry research 2015年第4期26卷 1049-1055页

作者： Zhigang Zhao Junjie Guo Chunsheng Wang Jie Zeng research institute of Tropical forestry CAF

We studied the formation of heartwood in Ery- throphleumfordii Oliv., an endangered rosewood species, by cross-section analysis on 52 stumps aged 28-57 years and arbitrarily sampled from natural forests in South China. Width and area of heartwood were positively correlated with age and xylem width （XW）, and were independent of annual radial growth. The proportions of heartwood and sapwood areas were equal at about 40 years. The heartwood formation pro- cess was simulated by linear regression of age and XW.

关键词： Erythrophleum fordii Growth process Heartwood formation Heartwood width Rosewoodspecies