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中国湿地保护恢复策略研究 被引量:38
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作者 安树青 张轩波 +3 位作者 张海飞 沈美亚 王怡道 陈俊 《湿地科学与管理》 2019年第2期41-44,共4页
中国湿地保护恢复取得了一定的成效,但依然存在以下问题:湿地威胁加剧、自然修复为主难以满足湿地恢复的需求、小微湿地生态问题被忽视和经济发展的积极效应没有充分发挥等。提出了中国湿地保护恢复由抢救性保护转向全面保护,合理选择... 中国湿地保护恢复取得了一定的成效,但依然存在以下问题:湿地威胁加剧、自然修复为主难以满足湿地恢复的需求、小微湿地生态问题被忽视和经济发展的积极效应没有充分发挥等。提出了中国湿地保护恢复由抢救性保护转向全面保护,合理选择湿地恢复等级,自然恢复与人工修复并重、注意中度干扰应用和创新湿地保护恢复新模式等策略。 展开更多
关键词 中国 湿地保护恢复 策略
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Rice leaf inclination2, a VIN3-1ike protein, regulates leaf angle through modulating cell division of the collar 被引量:34
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作者 shu-qing Zhao Jiang Hu +2 位作者 Long-Biao Guo Qian Qian Hong-Wei Xue 《Cell Research》 SCIE CAS CSCD 2010年第8期935-947,共13页
As an important agronomic trait, inclination of leaves is crucial Ior crop architecture and grain yields. 10 understand the molecular mechanism controlling rice leaf angles, one rice leaf inclination2 (1c2, three all... As an important agronomic trait, inclination of leaves is crucial Ior crop architecture and grain yields. 10 understand the molecular mechanism controlling rice leaf angles, one rice leaf inclination2 (1c2, three alleles) mutant was identified and functionally characterized. Compared to wild-type plants, lc2 mutants have enlarged leaf angles due to increased cell division in the adaxial epidermis of lamina joint. The LC2 gene was isolated through positional cloning, and encodes a vernalization insensitive 3-like protein. Complementary expression of LC2 reversed the enlarged leaf angles of lc2 plants, confirming its role in controlling leaf inclination. LC2 is mainly expressed in the lamina joint during leaf development, and particularly, is induced by the phytohormones abscisic acid, gibberellic acid, auxin, and brassinosteroids. LC2 is localized in the nucleus and defects of LC2 result in altered expression of cell division and hormone-responsive genes, indicating an important role of LC2 in regulating leaf inclination and mediating hormone effects. 展开更多
关键词 leaf inclination RICE VIN3-1ike protein cell division LC2
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The first data release(DR1) of the LAMOST regular survey 被引量:29
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作者 A-Li Luo Yong-Heng Zhao +134 位作者 Gang Zhao Li-Cai Deng Xiao-Wei Liu Yi-Peng Jing Gang Wang Hao-Tong Zhang Jian-Rong Shi Xiang-Qun Cui Yao-Quan Chu Guo-Ping Li Zhong-Rui Bai Yue Wu Yan Cai shu-Yun Cao Zi-Huang Cao Jeffrey L.Carlin Hai-Yuan Chen Jian-Jun Chen Kun-Xin Chen Li Chen Xue-Lei Chen Xiao-Yan Chen Ying Chen Norbert Christlieb Jia-Ru Chu Chen-Zhou Cui Yi-Qiao Dong Bing Du Dong-Wei Fan Lei Feng Jian-Ning Fu Peng Gao Xue-Fei Gong Bo-Zhong Gu Yan-Xin Guo Zhan-Wen Han Bo-Liang He Jin-Liang Hou Yong-Hui Hou Wen Hou Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Zhi-Ying Huo Lei Jia Fang-Hua Jiang Xiang Jiang Zhi-Bo Jiang Ge Jin Xiao Kong Xu Kong Ya-Juan Lei Ai-Hua Li Chang-Hua Li Guang-Wei Li Hai-Ning Li Jian Li Qi Li shuang Li Sha-Sha Li Xin-Nan Li Yan Li Yin-Bi Li Ye-Ping Li Yuan Liang Chien-Cheng Lin Chao Liu Gen-Rong Liu Guan-Qun Liu Zhi-Gang Liu Wen-Zhi Lu Yu Luo Yin-Dun Mao Heidi Newberg Ji-Jun Ni Zhao-Xiang Qi Yong-Jun Qi Shi-Yin Shen Huo-Ming Shi Jing Song Yi-Han Song Ding-Qiang Su Hong-Jun Su Zheng-Hong Tang qing-Sheng Tao Yuan Tian Dan Wang Da-Qi Wang Feng-Fei Wang Guo-Min Wang Hai Wang Hong-Chi Wang Jian Wang Jia-Ning Wang Jian-Ling Wang Jian-Ping Wang Jun-Xian Wang Lei Wang Meng-Xin Wang Shou-Guan Wang shu-qing Wang Xia Wang Ya-Nan Wang You Wang Yue-Fei Wang You-Fen Wang Peng Wei Ming-Zhi Wei Hong Wu Ke-Fei Wu Xue-Bing Wu Yu-Zhong Wu Xiao-Zheng Xing Ling-Zhe Xu Xin-Qi Xu Yan Xu Tai-Sheng Yan De-Hua Yang Hai-Feng Yang Hui-Qin Yang Ming Yang Zheng-Qiu Yao Yong Yu Hui Yuan Hai-Bo Yuan Hai-Long Yuan Wei-Min Yuan Chao Zhai En-Peng Zhang Hua-Wei Zhang Jian-Nan Zhang Li-Pin Zhang Wei Zhang Yong Zhang Yan-Xia Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第8期1095-1124,共30页
The Large sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST) general survey is a spectroscopic survey that will eventually cover approximately half of the celestial sphere and collect 10 million spectra of ... The Large sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST) general survey is a spectroscopic survey that will eventually cover approximately half of the celestial sphere and collect 10 million spectra of stars, galaxies and QSOs. Objects in both the pilot survey and the first year regular survey are included in the LAMOST DR1. The pilot survey started in October 2011 and ended in June 2012, and the data have been released to the public as the LAMOST Pilot Data Release in August 2012. The regular survey started in September 2012, and completed its first year of operation in June 2013. The LAMOST DR1 includes a total of 1202 plates containing 2 955 336 spectra, of which 1 790 879 spectra have observed signalto-noise ratio(SNR) ≥ 10. All data with SNR ≥ 2 are formally released as LAMOST DR1 under the LAMOST data policy. This data release contains a total of 2 204 696 spectra, of which 1 944 329 are stellar spectra, 12 082 are galaxy spectra and 5017 are quasars. The DR1 not only includes spectra, but also three stellar catalogs with measured parameters: late A,FGK-type stars with high quality spectra(1 061 918 entries), A-type stars(100 073 entries), and M-type stars(121 522 entries). This paper introduces the survey design, the observational and instrumental limitations, data reduction and analysis, and some caveats. A description of the FITS structure of spectral files and parameter catalogs is also provided. 展开更多
关键词 techniques: spectroscopic survey—data release—catalog
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Effects of cadium, zinc and lead on soil enzyme activities 被引量:29
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作者 YANG Zhi-xin LIU shu-qing +1 位作者 ZHENG Da-wei FENG Sheng-dong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第6期1135-1141,共7页
Heavy metal (HM) is a major hazard to the soil-plant system. This study investigated the combined effects of cadium (Cd), zinc (Zn) and lead (Pb) on activities of four enzymes in soil, including calatase, urea... Heavy metal (HM) is a major hazard to the soil-plant system. This study investigated the combined effects of cadium (Cd), zinc (Zn) and lead (Pb) on activities of four enzymes in soil, including calatase, urease, invertase and alkalin phosphatase. HM content in tops of canola and four enzymes activities in soil were analyzed at two months after the metal additions to the soil. Pb was not significantly inhibitory than the other heavy metals for the four enzyme activities and was shown to have a protective role on calatase activity in the combined presence of Cd, Zn and Pb; whereas Cd significantly inhibited the four enzyme activities, and Zn only inhibited urease and calatase activities. The inhibiting effect of Cd and Zn on urease and calatase activities can be intensified significantly by the additions of Zn and Cd. There was a negative synergistic inhibitory effect of Cd and Zn on the two enzymes in the presence of Cd, Zn and Pb. The urease activity was inhibited more by the HM combinations than by the metals alone and reduced approximately 20%--40% of urease activity. The intertase and alkaline phosphatase activities significantly decreased only with the increase of Cd concentration in the soil. It was shown that urease was much more sensitive to HM than the other enzymes. There was a obvious negative correlation between the ionic impulsion of HM in soil, the ionic impulsion of HM in canola plants tops and urease activity. It is concluded that the soil urease activity may be a sensitive tool for assessing additive toxic combination effect on soil biochemical parameters. 展开更多
关键词 multiple heavy metal pollution canola plants soil enzyme ionic impulsion
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A Mitochondrial Genome Sequence of the Tibetan Antelope(Pantholops hodgsonii) 被引量:22
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作者 shu-qing Xu Ying-Zhong Yang +8 位作者 Jun Zhou Guo-En Jing Yun-Tian Chen Jun Wang Huan-Ming Yang Jian Wang Jun Wu Xiao-Guang Zheng and Ri-Li Ge 《Genomics, Proteomics & Bioinformatics》 SCIE CAS CSCD 2005年第1期5-17,共13页
To investigate genetic mechanisms of high altitude adaptations of native mammals on the Tibetan Plateau, we compared mitochondrial sequences of the endangered Pantholops hodgsonii with its lowland distant relatives Ov... To investigate genetic mechanisms of high altitude adaptations of native mammals on the Tibetan Plateau, we compared mitochondrial sequences of the endangered Pantholops hodgsonii with its lowland distant relatives Ovis ames and Capra hircus, as well as other mammals. The complete mitochondrial genome of P. hodgsonii (16,498 bp) revealed a similar gene order as of other mammals. Because of tandem duplications, the control region of P. hodgsonii mitochondrial genome is shorter than those of O. ames and C. hircus, but longer than those of Bos species. Phylogenetic analysis based on alignments of the entire cytochrome b genes suggested that P. hodgsonii is more closely related to O. ames and C. hircus, rather than to species of the Antilopinae subfamily. The estimated divergence time between P. hodgsonii and O. ames is about 2.25 million years ago. Eutther analysis on natural selection indicated that the COXI (cytochrome c oxidase subunit I) gene was under positive selection in P. hodgsonii and Bos grunniens. Considering the same climates and environments shared by these two mammalian species, we proposed that the mitochondrial COXI gene is probably relevant for these native mammals to adapt the high altitude environment unique to the Tibetan Plateau. 展开更多
关键词 tibetan antelope mitochondrial genome ADAPTATION COXI
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Low- and Mid-High Latitude Components of the East Asian Winter Monsoon and Their Reflecting Variations in Winter Climate over Eastern China 被引量:20
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作者 LIU Ge JI Li-Ren +1 位作者 SUN shu-qing XIN Yu-Fei 《Atmospheric and Oceanic Science Letters》 2012年第3期195-200,共6页
The present study defines a low-latitude component (regionally averaged winter 1000-hPa V-winds over 10 25°N, 105 135°E) and a mid-high-latitude component (regionally averaged winter 1000-hPa V-winds over 30... The present study defines a low-latitude component (regionally averaged winter 1000-hPa V-winds over 10 25°N, 105 135°E) and a mid-high-latitude component (regionally averaged winter 1000-hPa V-winds over 30 50°N, 110 125°E) of the East Asian winter monsoon (EAWM), which are denoted as EAWM-L and EAWM-M, respectively. The study examines the variation characteristics, reflecting variations in winter climate over eastern China, and associated atmospheric circulations corresponding to the two components. The main results are as follows: 1) the EAWM-L and EAWM-M have consistent variation in some years but opposite variations in other years; 2) the EAWM-M index mainly reflects the extensive temperature variability over eastern China, while the EAWM-L index better reflects the variation in winter precipitation over most parts of eastern China; and 3) corresponding to the variation in the EAWM-M index, anomalous winds over the mid-high latitudes of East Asia modulate the southward invasion of cold air from the high latitudes and accordingly affect temperatures over eastern China. In combination with the variation in the EAWM-L index, anomalous low-latitudinal winds regulate the water vapor transport from tropical oceans to eastern China, resulting in anomalous winter precipitation. These pronounced differences between the EAWM-L and the EAWM-M suggest that it is necessary to explore the monsoons' individual features and effects in the EAWM study. 展开更多
关键词 East Asian winter monsoon TEMPERATURE PRECIPITATION eastern China
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Studies on the Rice LEAF INCLINATION1 (LC1), an IAA-amido Synthetase, Reveal the Effects of Auxin in Leaf Inclination Control 被引量:19
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作者 shu-qing Zhao Jing-Jing Xiang Hong-Wei Xue 《Molecular Plant》 SCIE CAS CSCD 2013年第1期174-187,共14页
The angle of rice leaf inclination is an important agronomic trait and closely related to the yields and archi- tecture of crops. Although few mutants with altered leaf angles have been reported, the molecular mechani... The angle of rice leaf inclination is an important agronomic trait and closely related to the yields and archi- tecture of crops. Although few mutants with altered leaf angles have been reported, the molecular mechanism remains to be elucidated, especially whether hormones are involved in this process. Through genetic screening, a rice gain-of- function mutant leaf inclination1, Icl-D, was identified from the Shanghai T-DNA Insertion Population (SHIP). Phenotypic analysis confirmed the exaggerated leaf angles of Icl-D due to the stimulated cell elongation at the lamina joint. LC1 is transcribed in various tissues and encodes OsGH3-1, an indole-3-acetic acid (IAA) amido synthetase, whose homolog of Arabidopsis functions in maintaining the auxin homeostasis by conjugating excess IAA to various amino acids. Indeed, recombinant LC1 can catalyze the conjugation of IAA to Ala, Asp, and Asn in vitro, which is consistent with the decreased free IAA amount in Icl-D mutant. Icl-D is insensitive to IAA and hypersensitive to exogenous BR, in agreement with the microarray analysis that reveals the altered transcriptions of genes involved in auxin signaling and BR biosynthesis. These results indicate the crucial roles of auxin homeostasis in the leaf inclination control. 展开更多
关键词 rice leaf inclination AUXIN GH3.
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Expression of trefoil factors 1 and 2 in precancerous condition and gastric cancer 被引量:14
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作者 shu-qing Shi Jian-Ting Cai Jian-Ming Yang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第19期3119-3122,共4页
AIM: To study the expression of trefoil factor 1 (TFF1) and TFF2 in precancerous condition and gastric cancer and to explore the relationship between TFFs and tumorigenesis, precancerous condition and gastric cance... AIM: To study the expression of trefoil factor 1 (TFF1) and TFF2 in precancerous condition and gastric cancer and to explore the relationship between TFFs and tumorigenesis, precancerous condition and gastric cancer. METHODS: The expression of TFF1 and TFF2 was immunohistochemically analyzed in paraffin-embedded samples from 140 patients including 35 cases of chronic superficial gastritis (CSG), 35 cases of gastric ulcer (GU), 35 cases of chronic atrophic gastritis (CAG) and 35 cases of gastric cancer (GC). RESULTS: TFF1 and TFF2 were located in cytoplasm of gastric mucous cells. In CSG, GU, CAG and GC, the level of TFF1 expression had a decreased tendency (P〈 0.05). The expression of TFF2 was higher in GU than in CSG, but the difference was not significant. The expression of TFF2 also had a decreased tendency in GU, CAG, and GC (P〈 0.05). CONCLUSION: The reduced expression of TFF1 and TFF2 in precancerous conditions and gastric cancer may be associated with the proliferation and malignant transformation of gastric mucosa. More investigations are needed to explore the mechanism of TFFs and the relationship between TFFs and gastric cancer. 展开更多
关键词 Trefoil factor Gastric cancer IMMUNOHISTOCHEMISTRY
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Ultrasound-guided paravertebral nerve block anesthesia on the stress response and hemodynamics among lung cancer patients 被引量:12
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作者 shu-qing Zhen Ming Jin +3 位作者 Yong-Xue Chen Jian-Hua Li Hua Wang Hui-Xia Chen 《World Journal of Clinical Cases》 SCIE 2022年第7期2174-2183,共10页
BACKGROUND Thoracic surgery for radical resection of lung tumor requires deep anesthesia which can lead to an adverse inflammatory response,loss of hemodynamic stability,and decreased immune function.Herein,we evaluat... BACKGROUND Thoracic surgery for radical resection of lung tumor requires deep anesthesia which can lead to an adverse inflammatory response,loss of hemodynamic stability,and decreased immune function.Herein,we evaluated the feasibility and benefits of ultrasound-guided paravertebral nerve block anesthesia,in combination with general anesthesia,for thoracic surgery for lung cancer.The block was performed by diffusion of anesthetic drugs along the paravertebral space to achieve unilateral multi-segment intercostal nerve and dorsal branch nerve block.AIM To evaluate the application of ultrasound-guided paravertebral nerve block anesthesia for lung cancer surgery to inform practice.METHODS The analysis was based on 140 patients who underwent thoracic surgery for lung cancer at our hospital between January 2018 and May 2020.Patients were randomly allocated to the peripheral+general anesthesia(observation)group(n=74)or to the general anesthesia(control)group(n=66).Patients in the observation group received ultrasound-guided paravertebral nerve block anesthesia combined with general anesthesia,with those in the control group receiving an epidural block combined with general anesthesia.Measured outcomes included the operative and anesthesia times,as well as the mean arterial pressure(MAP),heart rate(HR),and blood oxygen saturation(SpO;)measured before surgery,15 min after anesthesia(T1),after intubation,5 min after skin incision,and before extubation(T4).RESULTS The dose of intra-operative use of remifentanil and propofol and the postoperative use of sufentanil was lower in the observation group(1.48±0.43 mg,760.50±92.28 mg,and 72.50±16.62 mg,respectively)than control group(P<0.05).At the four time points of measurement(T1 through T4),MAP and HR values were higher in the observation than control group(MAP,90.20±9.15 mmHg,85.50±7.22 mmHg,88.59±8.15 mmHg,and 90.02±10.02 mmHg,respectively;and HR,72.39±8.22 beats/min,69.03±9.03 beats/min,70.12±8.11 beats/min,and 71.24±9.01 beats/min,respectively;P<0.05).There was 展开更多
关键词 Ultrasound-guided paravertebral nerve block anesthesia ANESTHESIA Lung cancer Stress response HEMODYNAMICS
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Improving effect of Ginkgolide B on mitochondrial respiration of ischemic neuron after cerebral thrombosis in tree shrews 被引量:13
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作者 LI shu-qing ZHANG Ying YANG Li-jun 《Chinese Medical Journal》 SCIE CAS CSCD 2007年第17期1529-1533,共5页
Background It has been known that platelet activating factor receptors (PAFR) may mediate many acute pathological responses and that PAFR antagonist Ginkgolide B (GB) possesses multiple effects, but the actions of... Background It has been known that platelet activating factor receptors (PAFR) may mediate many acute pathological responses and that PAFR antagonist Ginkgolide B (GB) possesses multiple effects, but the actions of GB on PAFR affinity and mitochondrial respiration in the ischemic neuron were unclear until now. This study explored the possible effects of GB on PAFR and the mitochondrial respiration of the neuron in the ischemic microenvironment. Methods Thrombotic cerebral ischemia in tree shrews was induced by a photochemical reaction; changes in the regional cerebral blood flow (rCBF, using ^99rnTc tracer technique ), the brain water content (specific gravimetric method), PAFR (3H-labelled PAF assay), the respiratory control rate (RCR), the phosphorus-oxygen (P/O) ratio of mitochondrial respiration (Clark oxygen electrode), mitochonddal permeability transition (MPT) pore, and the mitochondrial ultrastructure in the ischemic neurons were also observed. Data were compared between the two groups (the ischemia group vs the sham group, and the ischemia group vs the GB group). Results There were high affinity and low affinity sites for PAFR on the tree threws' brain cell membranes. The varying-affinity PAFR binding sites, the respiration state Ⅲ, the state Ⅳ, RCR, the P/O ratio of the mitochondria, and the rCBF all decreased markedly (respectively, P〈0.01 and P〈0.05), but the water content increased (P〈0.01) in the ischemia group after the application of cerebral thrombosis. In tree shrews treated with GB (5 mg/kg i.v.) 6 hours after photochemical reaction, their PAFR binding sites and respiratory state increased markedly. The rCBF gradually increased and the brain edema ameliorated (P〈0.01) at 24h after cerebral ischemia. There were significant differences between the ischemJa group and sham group (P〈0.01). In GB treated isolated neurons' mitochondria, with or without cerebral ischemia, the energy metabolism of the mitochondria had not bee 展开更多
关键词 PHOTOCHEMISTRY cerebral ischemia MITOCHONDRIA GINKGOLIDE tree shrews
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Wheat Growth and Photosynthesis as Affected by Oxytetracycline as a Soil Contaminant 被引量:12
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作者 LI Zhao-Jun XIE Xiao-Yu ZHANG shu-qing LIANG Yong-Chao 《Pedosphere》 SCIE CAS CSCD 2011年第2期244-250,共7页
Extensive worldwide use of oxytetracycline (OTC), a member of the tetracyclines, has resulted in its accumulation in soils, posing a potential risk to food production and safety. A pair of OTC-sensitive (Heyou 1) ... Extensive worldwide use of oxytetracycline (OTC), a member of the tetracyclines, has resulted in its accumulation in soils, posing a potential risk to food production and safety. A pair of OTC-sensitive (Heyou 1) and OTC-tolerant (Yannong 21) wheat (Tritieum aestivum L.) cultivars was compared hydroponically at 0.01, 0.02, 0.04, and 0.08 mmol L-10TC in terms of wheat growth and photosynthesis. Biomass and shoot length decreased significantly with the addition of OTC, with the decreases in dry biomass and shoot length being 5.61%-13.75% and 3.33%-8.57% larger, respectively, for Heyou 1 than Yannong 21. Photosynthesis of Heyou 1 was suppressed by OTC as indicated by the significant decreases in photosynthetic rate (PN), transpiration rate (TR), and stomatal conductance (GS) and the significant increase in intercellular CO2 concentrations (CI), at all OTC levels. Stomatal limitation (LS) and water use eftlciencies (WUE) of Heyou i also increased significantly, but not at 0.08 mmol L-10TC. However, photosynthesis of Yannong 21 was suppressed by OTC only at high OTC levels from 0.02 to 0.08 mmol L-1 as indicated by the decreases in PN, GS, TR, and LS; at 0.01 mmol L-10TC, PN, CI, GS, and TR significantly increased. It was noted that WUE of Yannong 21 was not affected by OTC addition. The results from this hydroponic test suggested that OTC had a potential risk to crop growth through inhibition of photosynthesis, requiring further confirmation with soil tests. 展开更多
关键词 biomass CULTIVAR hydroponic test photosynthetic parameters TETRACYCLINES
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基于自然解决方案理念的湿地一体化生态修复:以广西大新黑水河国家湿地公园为例 被引量:11
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作者 忻飞 杨棠武 +4 位作者 邵一奇 农梅英 尹树捷 安树青 张轩波 《湿地科学与管理》 2021年第4期28-32,共5页
通过查阅资料及调查发现广西大新黑水河国家湿地公园存在农村生活污水直排、废弃采砂场生态环境破坏严重、洲岛鸟类栖息地丧失及水土流失现象加剧等生态问题。基于自然解决方案(NbS)的理念,针对上述问题设计了一体化生态修复方案,主要... 通过查阅资料及调查发现广西大新黑水河国家湿地公园存在农村生活污水直排、废弃采砂场生态环境破坏严重、洲岛鸟类栖息地丧失及水土流失现象加剧等生态问题。基于自然解决方案(NbS)的理念,针对上述问题设计了一体化生态修复方案,主要工程措施有农村人工湿地构建工程、废弃采砂场生态修复工程、鸟类栖息地修复工程及河流原型水岸维护工程。一体化生态修复改善了黑水河国家湿地公园的生态环境,增加了生物多样性,提升了湿地生态功能,初步实现了“山水林田湖草”等生态系统的有机结合,促进了区域生态系统的健康发展。 展开更多
关键词 黑水河国家湿地公园 基于自然解决方案 生态修复
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X射线荧光光谱法测定土壤样品中的氟 被引量:11
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作者 李小莉 李庆霞 +2 位作者 安树清 张勤 郝国杰 《分析化学》 SCIE EI CAS CSCD 北大核心 2019年第11期1864-1869,共6页
污染的土壤及水系沉积物中氟(F)具有长期积累效应,因此测定土壤中的F具有重要意义。F是超轻元素,激发效率低,荧光产额低,且在光路中易被吸收。为提高F测定的分辨率,改善信背比,本研究使用PX8晶体为分析晶体,比PX1晶体信背比提高近2倍。... 污染的土壤及水系沉积物中氟(F)具有长期积累效应,因此测定土壤中的F具有重要意义。F是超轻元素,激发效率低,荧光产额低,且在光路中易被吸收。为提高F测定的分辨率,改善信背比,本研究使用PX8晶体为分析晶体,比PX1晶体信背比提高近2倍。低原子序数元素X射线的强度在很大程度上取决于基体的组分,为减少吸收/增强效应对F测定的影响,仅采用35个土壤标准物质建立F的校准曲线,经谱线重叠干扰校正、基体效应校正,方法的线性关系良好(R 2=0.978),测定限为50μg/g。采用28个土壤样品验证方法的可靠性,结果表明,X射线荧光光谱法可满足土壤样品中F测定误差的要求。 展开更多
关键词 土壤样品 X射线荧光光谱法 吸收/增强效应 分析晶体
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Changes of Bacterial Community Structure in Copper Mine Tailings After Colonization of Reed (Phragmites communis) 被引量:10
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作者 CHEN Yu-qing REN Guan-Ju +3 位作者 AN shu-qing SUN qing-Ye LIU Chang-Hong shuANG Jing-Lei 《Pedosphere》 SCIE CAS CSCD 2008年第6期731-740,共10页
Soil samples were collected from both bare and vegetated mine railings to study the changes in bacterial communities and soil chemical properties of copper mine tailings due to reed (Phragmites communis) colonizatio... Soil samples were collected from both bare and vegetated mine railings to study the changes in bacterial communities and soil chemical properties of copper mine tailings due to reed (Phragmites communis) colonization. The structures of bacterial communities were investigated using culture-independent 16S rRNA gene sequencing method. The bacterial diversity in the bare mine tailing was lower than that of the vegetated mine tailing. The former was dominated by sulfur metabolizing bacteria, whereas the latter was by nitrogen fixing bacteria. The bare mine tailing was acidic (pH = 3.78), whereas the vegetated mine tailing was near neutral (pH : 7.28). The contents of organic matter, total nitrogen, and ammonium acetate-extractable potassium in vegetated mine tailings were significantly higher than those in the bare mine railings (P 〈 0.01), whereas available phosphorus and electrical conductivity were significantly lower than those in the bare mine tailings (P 〈 0.01). The results demonstrated that 16S rRNA gene sequencing could be successfully used to study the bacterial diversity in mine tailings. The colonization of the mine tailings by reed significantly changed the bacterial community and the chemical properties of tailings. The complex interactions between bacteria and plants deserve further investigation. 展开更多
关键词 16S rRNA gene bacterial diversity bacterial community functional group mine tailings
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Seasonal Variation and Correlation with Environmental Factors of Photosynthesis and Water Use Efficiency of Juglans regia and Ziziphus jujuba 被引量:9
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作者 Hai-Bo Yang shu-qing An +4 位作者 Osbert-Jianxin Sun Zuo-Min Shi Xin-Song She qing-Ye Sun Shi-Rong Liu 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2008年第2期210-220,共11页
Both the photosynthetic light curves and CO2 curves of Juglans regia L. and Ziziphus jujuba Mill. var. spinosa in three seasons were measured using a LI-6400 portable photosynthesis system. The maximal net photosynthe... Both the photosynthetic light curves and CO2 curves of Juglans regia L. and Ziziphus jujuba Mill. var. spinosa in three seasons were measured using a LI-6400 portable photosynthesis system. The maximal net photosynthetic rate (Amax), apparent quantum efficiency(φ), maximal carboxylation rate (Vcmax) and water use efficiency (WUE) of the two species were calculated based on the curves. The results showed that Amax of J. regia reached its maximum at the late-season, while the highest values of Amax of Z. jujuba occurred at the mid-season. The Amax of J. regia was more affected by relative humidity (RH) of the atmosphere, while that of Z. jujuba was more affected by the air temperature. Light saturation point (LSP) and Light compensation point (LCP) of J. regia had a higher correlation with RH of the atmosphere, those of Z. jujuba, however, had a higher correlation with air temperature. Vcmax of both J. regia and Z. jujuba had negative correlation with RH of the atmosphere. WUE of J. regia would decrease with the rise of the air temperature while that of Z. jujuba increased. Thus it could be seen that RH, temperature and soil moisture had main effect on photosynthesis and WUE of J. regia and Z. jujuba. Incorporating data on the physiological differences among tree species into forest carbon models will greatly improve our ability to predict alterations to the forest carbon budgets under various environmental scenarios such as global climate change, or with differing species composition. 展开更多
关键词 apparent quantum efficiency (φ) maximal carboxylation rate (Vcrnax) net photosynthetic rate (Pn) returning cropland to forest or grassland seasonal variation water use efficiency (WUE).
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Negative Effects of Oxytetracycline on Wheat (Triticum aestivum L.) Growth, Root Activity, Photosynthesis, and Chlorophyll Contents 被引量:10
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作者 LI Zhao-jun XIE Xiao-yu ZHANG shu-qing LIANG Yong-chao 《Agricultural Sciences in China》 CAS CSCD 2011年第10期1545-1553,共9页
A solution culture experiment was performed to investigate the effects of oxytetracycline (OTC) on wheat (Triticum aestivum L.) growth, chlorophyll contents, and photosynthesis at five levels of 0, 10, 20, 40, and... A solution culture experiment was performed to investigate the effects of oxytetracycline (OTC) on wheat (Triticum aestivum L.) growth, chlorophyll contents, and photosynthesis at five levels of 0, 10, 20, 40, and 80 mmol L-1 OTC. OTC is toxic to wheat. The wheat growth, especially wheat root was significantly decreased. Further OTC also significantly decreased root activity, chlorophyll contents, and photosynthetic parameters except for intercellular CO2 concentrations. The different responses of indicators such as root number, root activity and so on to OTC were also observed. The IC50 values for the tested indicators to OTC ranged from 7.1 to 113.4 mmol L-1 OTC. The order of indicator sensitivity to OTC was root number stomatal conductance chlorophyll a total chlorophyll photosynthetic rates total surface area transpiration rate chlorophyll b fresh weight of root dry weight of root total length dry weight of shoot = fresh weight of shoot total volume. The root number was more sensitive than other indicators with the IC50 value of 7.1 mmol L-1 OTC, and could be taken as the sensitive indicator to predict the hazards of OTC to wheat. 展开更多
关键词 OTC WHEAT GROWTH root morphological characteristics chlorophyll contents PHOTOSYNTHESIS
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Impact of climate change on maize yield in China from 1979 to 2016 被引量:10
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作者 WU Jian-zhai ZHANG Jing +4 位作者 GE Zhang-ming XING Li-wei HAN shu-qing SHEN Chen KONG Fan-tao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第1期289-299,共11页
Climate change severely impacts agricultural production, which jeopardizes food security. China is the second largest maize producer in the world and also the largest consumer of maize. Analyzing the impact of climate... Climate change severely impacts agricultural production, which jeopardizes food security. China is the second largest maize producer in the world and also the largest consumer of maize. Analyzing the impact of climate change on maize yields can provide effective guidance to national and international economics and politics. Panel models are unable to determine the group-wise heteroscedasticity, cross-sectional correlation and autocorrelation of datasets, therefore we adopted the feasible generalized least square(FGLS) model to evaluate the impact of climate change on maize yields in China from 1979–2016 and got the following results:(1) During the 1979–2016 period, increases in temperature negatively impacted the maize yield of China. For every 1℃ increase in temperature, the maize yield was reduced by 5.19 kg 667 m^–2(1.7%). Precipitation increased only marginally during this time, and therefore its impact on the maize yield was negligible. For every 1 mm increase in precipitation, the maize yield increased by an insignificant amount of 0.043 kg 667 m^–2(0.014%).(2) The impacts of climate change on maize yield differ spatially, with more significant impacts experienced in southern China. In this region, a 1℃ increase in temperature resulted in a 7.49 kg 667 m^–2 decrease in the maize yield, while the impact of temperature on the maize yield in northern China was insignificant. For every 1 mm increase in precipitation, the maize yield increased by 0.013 kg 667 m^–2 in southern China and 0.066 kg 667 m^–2 in northern China.(3) The resilience of the maize crop to climate change is strong. The marginal effect of temperature in both southern and northern China during the 1990–2016 period was smaller than that for the 1979–2016 period. 展开更多
关键词 climate change maize yield FGLS model China
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Data release of the LAMOST pilot survey 被引量:8
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作者 A-Li Luo Hao-Tong Zhang +80 位作者 Yong-Heng Zhao Gang Zhao Xiang-Qun Cui Guo-Ping Li Yao-Quan Chu Jian-Rong Shi Gang Wang Jian-Nan Zhang Zhong-Rui Bai Xiao-Yan Chen Feng-Fei Wang Yan-Xin Guo Jian-Jun Chen Bing Du Xiao Kong Ya-Juan Lei Yin-Bi Li Yi-Han Song Yue Wu Yan-Xia Zhang Xin-Lin Zhou Fang Zuo Peng Du Lin He Wen Hou Yi-Qiao Dong Jian Li Guang-Wei Li shuang Li Jing Song Yuan Tian Meng-Xin Wang Yong-Hui Hou Zhi-Ying Huo Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Lei Jia Fang-Hua Jiang Xiang Jiang Zi-Bo Jiang Ge Jin Ai-Hua Li Qi Li Yin-Dun Mao Zheng-Hong Tang qing-Sheng Tao Liang-Ping Tu Da-qing Wang Dan Wang Jian-Ping Wang Lei Wang Shou-Guan Wang shu-qing Wang Ya-Nan Wang You Wang Yue-Fei Wang Ming-Zhi Wei Xiang-Xiang Xue Xiao-Zheng Xing Ling-Zhe Xu Xin-Qi Xu Yan Xu De-Hua Yang Shi-Hai Yang Zheng-Qiu Yao Yong Yu Hui Yuan Chao Zhai En-Peng Zhang Jing Zhang Li-Ping Zhang WeiZhang Yong Zhang Zhen-Chao Zhang Ming Zhao Fang Zhou Yong-Tian Zhu Jie Zhu Si-Cheng Zou 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第9期1243-1246,共4页
This paper describes the data release of the LAMOST pilot survey, which includes data reduction, calibration, spectral analysis, data products and data access. The accuracy of the released data and the information abo... This paper describes the data release of the LAMOST pilot survey, which includes data reduction, calibration, spectral analysis, data products and data access. The accuracy of the released data and the information about the FITS headers of spectra are also introduced. The released data set includes 319 000 spectra and a catalog of these objects. 展开更多
关键词 techniques: spectroscopic survey data reduction data release
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Role of three-dimensional endoanal ultrasound in assessing the anal sphincter morphology of female patients with chronic proctalgia 被引量:9
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作者 Ya-Hong Xue shu-qing Ding +1 位作者 Yi-Jiang Ding Li-Qun Pan 《World Journal of Gastroenterology》 SCIE CAS 2017年第21期3900-3906,共7页
AIM To assess the role of three-dimensional endoanal ultrasound (3D-EAUS) for morphological assessment of the anal sphincter of female patients with chronic proctalgia (CP). METHODS In this unmatched case control stud... AIM To assess the role of three-dimensional endoanal ultrasound (3D-EAUS) for morphological assessment of the anal sphincter of female patients with chronic proctalgia (CP). METHODS In this unmatched case control study, 30 consecutive female patients with CP and 25 normal women (control group) were enrolled. 3D-EAUS was performed in all subjects. Thickness and length of internal anal sphincter (IAS), thickness of puborectalis muscle (PR), length of the external anal sphincter (EAS) plus PR, and puborectalis angle were measured and compared between the two groups. RESULTS Patients with CP had significantly shorter IAS length and greater PR thickness, as compared to those in normal individuals (26.28 +/- 3.59 mm vs 28.87 +/- 4.84 mm, P < 0.05 and 9.67 +/- 1.57 mm vs 8.85 +/- 0.97 mm, P < 0.05, respectively). No significant between-group differences were observed with respect to IAS thickness and the EAS plus PR length (P > 0.05). Puborectalis angle in the CP group was significantly decreased, both in resting (88.23 degrees +/- 1.81 degrees vs 89.94 degrees +/- 2.07 degrees in control group, P < 0.05) and straining (88.47 degrees +/- 3.32 degrees vs 90.72 degrees +/- 1.87 degrees in control group, P < 0.05) phases, which suggest the presence of paradoxical contraction of PR in patients with CP. In the CP group, no significant difference in puborectalis angle was observed between the resting and straining phases (88.23 degrees +/- 1.81 degrees vs 88.47 degrees +/- 3.32 degrees respectively, P > 0.05). CONCLUSION The association of greater PR thickness and paradoxical contraction of PR with CP suggest their potential value as markers of CP. 展开更多
关键词 chronic proctalgia three-dimensional endoanal ultrasound puborectalis angle internal anal sphincter puborectalis muscle
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Automatic image segmentation method for cotton leaves with disease under natural environment 被引量:9
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作者 ZHANG Jian-hua KONG Fan-tao +2 位作者 WU Jian-zhai HAN shu-qing ZHAI Zhi-fen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第8期1800-1814,共15页
In order to improve the image segmentation performance of cotton leaves in natural environment, an automatic segmentation model of diseased leaf with active gradient and local information is proposed. Firstly, a segme... In order to improve the image segmentation performance of cotton leaves in natural environment, an automatic segmentation model of diseased leaf with active gradient and local information is proposed. Firstly, a segmented monotone decreasing edge composite function is proposed to accelerate the evolution of the level set curve in the gradient smooth region. Secondly, canny edge detection operator gradient is introduced into the model as the global information. In the process of the evolution of the level set function, the guidance information of the energy function is used to guide the curve evolution according to the local information of the image, and the smooth contour curve is obtained. And the main direction of the evolution of the level set curve is controlled according to the global gradient information, which effectively overcomes the local minima in the process of the evolution of the level set function. Finally, the Heaviside function is introduced into the energy function to smooth the contours of the motion and to increase the penalty function Φ(x) to calibrate the deviation of the level set function so that the level set is smooth and closed. The results showed that the model of cotton leaf edge profile curve could be obtained in the model of cotton leaf covered by bare soil, straw mulching and plastic film mulching, and the ideal edge of the ROI could be realized when the light was not uniform. In the complex background, the model can segment the leaves of the cotton with uneven illumination, shadow and weed background, and it is better to realize the ideal extraction of the edge of the blade. Compared with the Geodesic Active Contour(GAC) algorithm, Chan-Vese(C-V) algorithm and Local Binary Fitting(LBF) algorithm, it is found that the model has the advantages of segmentation accuracy and running time when processing seven kinds of cotton disease leaves images, including uneven lighting, leaf disease spot blur, adhesive diseased leaf, shadow, complex background, unclear diseased leaf edges, and sta 展开更多
关键词 local binary fitting model natural environment COTTON disease leaves image segmentation
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