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The History of Controlling and Treating Infectious Diseases in Ancient China 被引量:1
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作者 Cui-ling LIU Tao ZHOU +5 位作者 Liang-bin CHENG David FISHER Khrystyna PRONYUK Erkin MUSABAEV Yi-ping DANG Lei ZHAO 《Current Medical Science》 SCIE CAS 2024年第1期64-70,共7页
Infectious diseases are the common enemies of mankind.In the course of historical development,they persistently threaten human health and safety.Even today,despite the developments in medical science,we cannot escape ... Infectious diseases are the common enemies of mankind.In the course of historical development,they persistently threaten human health and safety.Even today,despite the developments in medical science,we cannot escape the fear and suffering caused by infectious diseases.Whether in ancient or modern times,the source of infection,route of transmission,and a susceptible population are the three key conditions for the prevalence and spread of infectious diseases.All factors closely related to these three conditions can affect the prevalence of infectious diseases.China is one of the cradles of world civilization.The ancient people accumulated a great deal of experience and lessons in the long struggle against infectious diseases.In the face of the current threat posed by widespread infectious disease,it is imperative to review and summarize ancient Chinese ideas and health policies on epidemic prevention and control to inspire contemporary efforts in the prevention and control of infectious disease.The combination of prevention-oriented epidemic prevention ideology and traditional medicine provides valuable insights,especially for impoverished and medically underserved regions. 展开更多
关键词 infectious diseases Chinese medicine public health historical review
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A Brief Overview of ChatGPT:The History,Status Quo and Potential Future Development 被引量:94
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作者 Tianyu Wu Shizhu He +4 位作者 Jingping Liu Siqi Sun Kang Liu Qing-Long Han Yang Tang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第5期1122-1136,共15页
ChatG PT,an artificial intelligence generated content (AIGC) model developed by OpenAI,has attracted worldwide attention for its capability of dealing with challenging language understanding and generation tasks in th... ChatG PT,an artificial intelligence generated content (AIGC) model developed by OpenAI,has attracted worldwide attention for its capability of dealing with challenging language understanding and generation tasks in the form of conversations.This paper briefly provides an overview on the history,status quo and potential future development of ChatGPT,helping to provide an entry point to think about ChatGPT.Specifically,from the limited open-accessed resources,we conclude the core techniques of ChatGPT,mainly including large-scale language models,in-context learning,reinforcement learning from human feedback and the key technical steps for developing ChatGPT.We further analyze the pros and cons of ChatGPT and we rethink the duality of ChatGPT in various fields.Although it has been widely acknowledged that ChatGPT brings plenty of opportunities for various fields,mankind should still treat and use ChatG PT properly to avoid the potential threat,e.g.,academic integrity and safety challenge.Finally,we discuss several open problems as the potential development of ChatGPT. 展开更多
关键词 AIGC ChatGPT GPT-3 GPT-4 human feedback large language models
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Variations in stem radii of Larix principis-rupprechtii to environmental factors at two slope locations in the Liupan Mountains,northwest China 被引量:7
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作者 Jing Ma Jianbin Guo +4 位作者 Yanhui Wang Zebin Liu Di Gao Liu Hong Ziyou Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第2期513-527,共15页
Relationships between stem growth and climatic and edaphic factors,notably air temperatures and soil moisture for different slopes,are not completely understood.Stem radial variations were monitored at the bottom and ... Relationships between stem growth and climatic and edaphic factors,notably air temperatures and soil moisture for different slopes,are not completely understood.Stem radial variations were monitored at the bottom and top slope positions in a Larix principis-rupprechtii plantation during the 2017 and 2018 growing seasons.Total precipitation during the growing season in 2017 and 2018 was 566 mm and 728 mm,respectively.Stem contractions typically occurred after mid-morning followed by swelling in the late afternoon in both plots,reflecting the diurnal cycle of water uptake and loss.Trees at the two locations showed the same growth initiation(mid-May)because of the small differences in air and soil temperatures.There were no significant differences in cumulative stem radial growth between the bottom plot(1.57±0.34 mm)and the top plot(1.55±0.26 mm)in 2018.However,in 2017,the main growth period of the bottom plot ceased 17 days earlier than in the top plot,while cumulative seasonal growth of the bottom plot(1.08±0.25 mm)was significantly less than the top plot(1.54±0.43 mm).Maximum daily stem shrinkage was positively correlated with air and soil temperatures,solar radiation,vapor pressure deficits,and negatively correlated with volumetric soil moisture content.The maximum daily shrinkage reflected transpiration rates as affected by environmental factors.Daily radial stem increment was correlated with precipitation and volumetric soil moisture in both years,but with air temperatures only in 2017.The seasonal growth of L.principis-rupprechtii Mayr thus shows interannual dynamics,while precipitation constitutes a key driving factor. 展开更多
关键词 Stem radial variations Main growth period Diurnal patterns Initiation temperatures Meteorological factors Larix principis-rupprechtii plantation
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Dual-priming oligonucleotide-based multiplex PCR using tissue samples in rapid urease test in the detection of Helicobacter pylori infection 被引量:10
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作者 Woo Chul Chung Sung Hoon Jung +6 位作者 Jung Hwan Oh Tae Ho Kim Dae Young Cheung Byung Wook Kim Sung Soo Kim Jin Il Kim Eun Young Sin 《World Journal of Gastroenterology》 SCIE CAS 2014年第21期6547-6553,共7页
AIM: To investigate whether tissue samples processed by the rapid urease test (RUT) kit are suitable for dual-priming oligonucleotide-based multiplex polymerase chain reaction (DPO-PCR) to detect Helicobacter pylori (... AIM: To investigate whether tissue samples processed by the rapid urease test (RUT) kit are suitable for dual-priming oligonucleotide-based multiplex polymerase chain reaction (DPO-PCR) to detect Helicobacter pylori (H. pylori). 展开更多
关键词 Helicobacter pylori Diagnosis Dual-priming oligonucleotide-based multiplex polymerase chain reaction
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Non-alcoholic fatty liver disease-a chronic disease of the 21^(st) century 被引量:4
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作者 Peter Metrakos Tommy Nilsson 《The Journal of Biomedical Research》 CAS CSCD 2018年第5期327-335,共9页
Non-alcoholic fatty liver disease(NAFLD) comprises a spectrum of metabolic states ranging from simple steatosis to inflammation with associated fibrosis to cirrhosis. Though accumulation of hepatic fat is not associ... Non-alcoholic fatty liver disease(NAFLD) comprises a spectrum of metabolic states ranging from simple steatosis to inflammation with associated fibrosis to cirrhosis. Though accumulation of hepatic fat is not associated with a significant increase in mortality rates, hepatic inflammation is, as this augments the risk of terminal liver disease, i.e.,cirrhosis, hepatic decompensation(liver failure) and/or hepatocellular carcinoma. Disease progression is usually slow, over a decade or more and, for the most part, remains asymptomatic. Recent estimates suggest that the global prevalence of NAFLD is high, about one in four. In most cases, NAFLD overlaps with overweight, obesity,cardiovascular disease and the metabolic syndrome with numerous contributing parameters including a dysregulation of adipose tissue, insulin resistance, type 2 diabetes, changes in the gut microbiome, neuronal and hormonal dysregulation and metabolic stress. NAFLD is diagnosed incidentally, despite its high prevalence. Non-invasive imaging techniques have emerged, making it possible to determine degree of steatosis as well asfibrosis. Despite this,the benefit of routine diagnostics remains uncertain. A better understanding of the(molecular) pathogenesis of NAFLD is needed combined with long-term studies where benefits of treatment can be assessed to determine costbenefit ratios. This review summarizes the current state of knowledge and possible areas of treatment. 展开更多
关键词 non-alcoholic fatty liver disease PATHOGENESIS molecular mechanism DIAGNOSTICS BIOMARKER
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The impact of climate change on fire risk in Daxing'anling,China 被引量:2
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作者 Xiaorui Tian Lifu Shu +1 位作者 Mingyu Wang Fengjun Zhao 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第5期997-1006,共10页
Daxing’anling is a key region for forest fire prevention in China. Assessing changes in fire risk in the future under multiple climatic scenarios will contribute to our understanding of the influences of climate chan... Daxing’anling is a key region for forest fire prevention in China. Assessing changes in fire risk in the future under multiple climatic scenarios will contribute to our understanding of the influences of climate change for the region and provide a reference for applying adaptive measures for fire management. This study analyzed the changes in fire weather indices and the fire season under four climate scenarios (RCP2.6, RCP4.5, RCP6.0, RCP8.5) for 2021-2050 using data from five global climate models together with observation data. The results showed that the analog data could project the average state of the climate for a given period but were not effective for simulating extreme weather conditions. Compared with the baseline period (1971-2000), the period 2021-2050 was predicted to have an increase in average temperature of 2.02-2.65 °C and in annual precipitation 25.4-40.3 mm, while the fire weather index (FWI) was predicted to increase by 6.2-11.2% and seasonal severity rating (SSR) by 5.5-17.2%. The DMC (Duff moisture code), ISI (initial spread index), BUI (build-up index), FWI and SSR were predicted to increase significantly under scenarios RCP4.5, RCP6.0, and RCP8.5. Furthermore, days with high or higher fire danger rating were predicted to be prolonged by 3-6 days, with the change in the southern region being greater under scenarios RCP4.5, RCP6.0, and RCP8.5. 展开更多
关键词 Climate change Fire danger Forest fire Fire season Fire weather indexes
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Valuation of Ecosystem Services:Research Progress and Prospects 被引量:3
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作者 FENG Ling 《Asian Agricultural Research》 2012年第10期75-79,共5页
The ecosystem services are material base and natural capital for sustainable development of human being. Valuation of ecosystem services is favorable for people realizing the importance of natural ecosystem to human b... The ecosystem services are material base and natural capital for sustainable development of human being. Valuation of ecosystem services is favorable for people realizing the importance of natural ecosystem to human being, and considering its long-term influence on sustainable development of human society when making decisions. Besides, it is an attempt of ecology, geography and other natural sciences to influence social decision process by economic methods. The Value of the World's Ecosystem Services and Natural Capital, written by Robert Costanza et al., in 1997, is generally regarded as a masterpiece for the research of valuing ecosystem services. However, the classifying standard of ecosystem services, the method of various services summation and the purpose for static global value, had confronted many criticisms. Still to now, accurately valuing ecosystem services is not easy, because of the complexity of natural ecosystem, the weak capability of economic system to pricing ecosystem services and the lack of more study in this field. Based on the criticisms summarizing and comprehensive analysis, further study suggestions of ecosystem services valuation is presented: multi-scale integrated and community participation applied in evaluation, dynamic changes of material value and intangible value of ecosystem services, investigation and simulation studies of the marginal value when ecosystem services changed, associated with related areas like ecological compensation research, and research on the market-oriented evaluation of ecosystem's intangible values. 展开更多
关键词 ECOSYSTEM SERVICES VALUE EVALUATION Research progr
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Spatial and temporal distribution of forest fire frequency and forest area burnt in Jilin Province, Northeast China 被引量:5
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作者 Qiang Liu Yanlong Shan +2 位作者 Lifu Shu Pingyan Sun Shuai Du 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第5期1233-1239,共7页
Forest fires caused by natural forces or human activities are one of the major natural risks in Northeast China.The incidence and spatial distribution of these fires vary over time and across the forested areas in Jil... Forest fires caused by natural forces or human activities are one of the major natural risks in Northeast China.The incidence and spatial distribution of these fires vary over time and across the forested areas in Jilin Province,Northeast China.In this study,the incidence and distribution of 6519 forest fires from 1969 to 2013 in the province were investigated.The results indicated that the spatiotemporal distribution of the burnt forest area and the fire frequency varied significantly by month,year,and region.Fire occurrence displayed notable temporal patterns in the years after forest fire prevention measures were strictly implemented by the provincial government.Generally,forest fires in Jilin occurred in months when stubble and straw were burned and human activities were intense during traditional Chinese festivals.Baishan city,Jilin city,and Yanbian were defined as fire-prone regions for their high fire frequency.Yanbian had the highest frequency,and the fires tended to be large with the highest burned area per fire.Yanbian should thus be listed as the key target area by the fire management agency in Jilin Province for better fire prevention. 展开更多
关键词 Fire intensity Forest fire Temporal distribution Spatial distribution
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Maxillary first premolars:Ⅰ.Morphology of the apical constriction 被引量:3
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作者 Darning Wu Younong Wu Ming Hu 《Journal of Nanjing Medical University》 2009年第6期420-424,共5页
Objective: To investigated the apical constriction morphology of maxillary first premolars in the Chinese population. Methods: Eighty recently extracted human maxillary first premolars from a native Chinese populati... Objective: To investigated the apical constriction morphology of maxillary first premolars in the Chinese population. Methods: Eighty recently extracted human maxillary first premolars from a native Chinese population were used. The number and shape of apical constrictions were recorded under a dental operating microscope (DOM) at 12.5 × 2.5 magnification. After access preparation, a new K-file was inserted into the canal until the tip of the file was just seen at the apical constriction under the DOM. The teeth with files in the canals were X-rayed from a mesiodistal direction using a direct digital radiography (DDR) system, and the distance between the file tip and the center of radiographic apex was directly measured from the computer screen using DDR measurement software. Results: The percentage of teeth with an apical constriction was 78.5% (102/130). The most common apical constriction shapes were oval (55.9%) and round (35.3%). The mean distance between the apical constriction and the anatomical tip of the root was 0.61 mm, and 84.3% (86/102) were within 1 mm. Conclusion: The most common shape of an apical constriction was oval or round, and the distance to the apex was mostly within 1 mm, indicating that root canal therapy should stop 1 mm from the radiographic apex. 展开更多
关键词 maxillary first premolar tooth root apical constriction anatomic apex
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Active Achilles tendon kinesitherapy accelerates Achilles tendon repair by promoting neurite regeneration 被引量:2
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作者 Jiasharete Jielile Minawa Aibai +10 位作者 Gulnur Sabirhazi Nuerai Shawutali Wulanbai Tangkejie Aynaz Badelhan Yeermike Nuerduola Turde Satewalede Darehan Buranbai Beicen Hunapia Ayidaer Jialihasi Jingping Bai Murat Kizaibek 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第35期2801-2810,共10页
Active Achilles tendon kinesitherapy facilitates the functional recovery of a ruptured Achilles tendon However, protein expression during the healing process remains a controversial issue. New Zealand rabbits, aged 14... Active Achilles tendon kinesitherapy facilitates the functional recovery of a ruptured Achilles tendon However, protein expression during the healing process remains a controversial issue. New Zealand rabbits, aged 14 weeks, underwent tenotomy followed immediately byAchilles tendon microsurgery to repair the Achilles tendon rupture. The tendon was then immobilized or subjected to postoperative early motion treatment (kinesitherapy). Mass spectrography results showed that after 14 days of motion treatment, 18 protein spots were differentially expressed, among which, 12 were up-regulated, consisting of gelsolin isoform b and neurite growth-related protein collapsing response mediator protein 2. Western blot analysis showed that gelsolin isoform b was up-regulated at days 7-21 of motion treatment. These findings suggest that active Achilles tendon kinesitherapy promotes the neurite regeneration of a ruptured Achilles tendon and gelsolin isoform b can be used as a biomarker for Achilles tendon healing after kinesitherapy. 展开更多
关键词 achilles tendon rupture early motion functional exercise EXERCISE Achilles tendon HEALING PROTEOMICS MARKER tissue repair
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Evaluation of the Protective Efficacy of a Fused OmpK/Omp22 Protein Vaccine Candidate against Acinetobacter baumannii Infection in Mice 被引量:5
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作者 GUO San Jun REN Shan XIE Yong En 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第2期155-158,共4页
Acinetobocter baumannfi (A. Baumannii) is an emerging opportunistic pathogen responsible for hospital-acquired infections, and which now constitutes a sufficiently serious threat to public health to necessitate the ... Acinetobocter baumannfi (A. Baumannii) is an emerging opportunistic pathogen responsible for hospital-acquired infections, and which now constitutes a sufficiently serious threat to public health to necessitate the development of an effective vaccine. In this study, a recombinant fused protein named OmpK/Omp22 and two individual proteins OmpK and Omp22 were obtained using recombinant expression and Ni-affinity purification. Groups of BALB/c mice were immunized with these proteins and challenged with a clinically isolated strain of A. boumonnii. The bacterial load in the blood, pathological changes in the lung tissue and survival rates after challenge were evaluated. Mice immunized with OmpK/Omp22 fused protein provided significantly greater protection against A. boumonnfi challenge than those immunized with either of the two proteins individually. The results provide novel clues for future design of vaccines against A. boumonnii. 展开更多
关键词 Evaluation of the Protective Efficacy of a Fused OmpK/Omp22 Protein Vaccine Candidate against Acinetobacter baumannii Infection in Mice
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The Development Trend of Developed Countries to Invest in Education of Disadvantaged Groups and the Enlightenment to Our Country 被引量:1
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作者 Ruan Ting Song Zhanmei 《学术界》 CSSCI 北大核心 2013年第9期288-297,共10页
Educational investment is the material basis for developing intelligence and educational cause and also an important factor for the development of economic and society.This paper argues that educational investment is ... Educational investment is the material basis for developing intelligence and educational cause and also an important factor for the development of economic and society.This paper argues that educational investment is an important strategy to solve the problem of disadvantaged groups in our country,and hopes that through the analysis of the structure and the trend for educational investment in developed countries,and it can provide reference and valuable suggestions for our country. 展开更多
关键词 教育投资 弱势群体 发达国家 发展趋势 物质基础 社会发展
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Advances in the phylogenesis of Agaricales and its higher ranks and strategies for establishing phylogenetic hypotheses 被引量:1
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作者 Rui-lin ZHAO Dennis E. DESJARDIN +1 位作者 Kasem SOYTONG Kevin D. HYDE 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2008年第10期779-786,共8页
We present an overview of previous research results on the molecular phylogenetic analyses in Agaricales and its higher ranks (Agaricomycetes/Agaricomycotina/Basidiomycota) along with the most recent treatments of tax... We present an overview of previous research results on the molecular phylogenetic analyses in Agaricales and its higher ranks (Agaricomycetes/Agaricomycotina/Basidiomycota) along with the most recent treatments of taxonomic systems in these taxa. Establishing phylogenetic hypotheses using DNA sequences, from which an understanding of the natural evolutionary relationships amongst clades may be derived, requires a robust dataset. It has been recognized that single-gene phylogenies may not truly represent organismal phylogenies, but the concordant phylogenetic genealogies from multiple-gene datasets can resolve this problem. The genes commonly used in mushroom phylogenetic research are summarized. 展开更多
关键词 Gene Molecular MUSHROOMS PHYLOGENY
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A study of emissions and marker gases from smouldering combustion in Larix gmelinii plantations of the Daxing'an Mountains 被引量:1
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作者 Shuyuan Tang Sainan Yin +6 位作者 Yanlong Shan Bo Gao Long Sun Xiyue Han Mingxia Wang Mingyu Wang Zongshi Chen 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第1期195-201,共7页
Underground fires are characterized by smouldering combustion with a slow rate of spread rate and without flames.Although smouldering combustion releases large amounts of gaseous pollutants,it is difficult to discover... Underground fires are characterized by smouldering combustion with a slow rate of spread rate and without flames.Although smouldering combustion releases large amounts of gaseous pollutants,it is difficult to discover by today's forest fire monitoring technologies.Carbon monoxide(CO),nitrogen oxides(NO_(x))and sulfur dioxide(SO_(2))were identified as high concentration marker gases of smouldering combustion-easily-be monitored.According to a two-way ANOVA,combustion time had a significant impact on CO and NO_(x) emissions;smoldering-depth also had a significant impact on NO_(x) emissions but not on CO emissions.Gas emission equations were established by multiple linear regression,C_(co)=156.989-16.626 t and C_(NOx)=3.637-0.252 t-0.039 h. 展开更多
关键词 Gas emissions Marker gases Infuence factors Smouldering combustion
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The effects of EMLA cream on pain responses of preschoolers 被引量:1
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作者 Se Na Ahn Joohyun Lee +3 位作者 Hae Won Kim Sook Bin Im Byung Sun Cho Hye Young Ahn 《Open Journal of Nursing》 2013年第8期1-4,共4页
The aim of present study was to assess the effects of a eutectic mixture of topical anesthetics (EMLA cream) on pain responses of preschoolers during venipuncture. The pain responses were reported by children, nurses,... The aim of present study was to assess the effects of a eutectic mixture of topical anesthetics (EMLA cream) on pain responses of preschoolers during venipuncture. The pain responses were reported by children, nurses, and the children’s mothers. The pre- and post-test-designed study, which included a non-equivalent control group, was carried out in a pediatric unit at E University Hospital in South Korea. Pain responses during venipuncture were measured by the self-reporting of the children using the Face Pain Rating Scale (FPRS), the Procedure Behavior Checklist by nurses (PBCL), the Visual Analog Scale (VAS) by mothers, in addition to measurements of the children’s pulse rate and level of oxygen saturation. EMLA cream was effective in decreasing the pain responses of the children as assessed by FPRS, PBCL, and VAS scores. However, pulse rate and level of oxygen saturation of the children during venipuncture were not significantly different between the two groups. EMLA cream could be a useful option for reducing pain in preschool children during invasive procedures. 展开更多
关键词 VENIPUNCTURE EMLA CREAM PAIN PRESCHOOLER
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The Production of 1,8-Cineole, a Potential Biofuel, from an Endophytic Strain of <i>Annulohypoxylon</i>sp. FPYF3050 When Grown on Agricultural Residues 被引量:1
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作者 K. Y. Wang G. A. Strobel D.-H. Yan 《Journal of Sustainable Bioenergy Systems》 2017年第2期65-84,共20页
An endophytic fungus producing 1,8-cineole from Neolitsea pulchella (Meissn.) Merr. was identified as Annulohypoxylon sp. by phylogenetic analyses of the sequence alignments of ITS rDNA, β-tubulin, Actin and EF1-α. ... An endophytic fungus producing 1,8-cineole from Neolitsea pulchella (Meissn.) Merr. was identified as Annulohypoxylon sp. by phylogenetic analyses of the sequence alignments of ITS rDNA, β-tubulin, Actin and EF1-α. This isolate produces an attractive spectrum of volatile organic compounds (VOCs) with only one dominant component, 1,8-cineole, as identified by gas chromatography-mass spectrometry (GC-MS). The fungus was able to grow in seven media with different carbon sources, and five raw agro-forest residues. The content of 1,8-cineole in the mixed VOCs via fungus reached up to 94.95% and 91.25% relative area in PDA and raw poplar sawdust, respectively. Under optimum test conditions, the fungus produced 1,8-cineole at the 0.764 ppmv in 50 mL head spaces in PDA. Interestingly, 1,8-cineole is an ideal fuel additive for both diesel and gasoline engines. Also, this is the first isolate, in this group of fungi, making cineole, which produces as its primary VOC product which makes it an ideal organism for strain improvement. Such as step will be critical for its ultimate use in biofuel production. 展开更多
关键词 1 8-Cineole Agro-Forest Residues ENDOPHYTIC Annulohypoxylon BIOFUEL FUNGAL VOCs
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Photosynthetic traits and antioxidative defense responses of Pinus yunnanensis after joint attack by bark beetles Tomicus yunnanensis and T.minor
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作者 Juan Liu Hang Chen +3 位作者 Jianmin Wang Xiaoming Chen Zixiang Yang Junsheng Liang 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第6期2031-2038,共8页
Bark beetles Tomicus yunnanensis and T.minor are two important pests of Pinus yunnanensis and can cause massive death of pine trees.In this study,we examined several traits related to photosynthesis in P.yunnanensis a... Bark beetles Tomicus yunnanensis and T.minor are two important pests of Pinus yunnanensis and can cause massive death of pine trees.In this study,we examined several traits related to photosynthesis in P.yunnanensis and their relationship with antibiotic defense responses after joint attack by the two bark beetles at the shoot and the trunk stages.When shoots were attacked by the beetles,the abundance of chlorophylls,carotenoids,and the rates of net photosynthesis(Pn)and transpiration(E)decreased in needles,while the levels of superoxide dismutase and malondialdehyde remained unchanged in both needles and phloem.The activity of peroxidases also remained unchanged in needles,but increased in phloem.The activity of catalases increased in both needles and phloem.When trunks were attacked by the bark beetles,chlorophyll abundance,Pn,E,and antioxidative enzyme activities all declined,and the declines were more pronounced than in the attacked shoots.A decrease in protein concentrations was also observed in needles and phloem from the attacked pines.Attack on shoots by the bark beetles suppressed host defense and provided a favorable environment for larval growth and development,resulting in long-term decline of pine growth potential.The results suggest that attacks on trunks by beetles caused more severe damage to host trees than attacks on shoots. 展开更多
关键词 Antioxidant enzymes BARK BEETLE Defense responses Photosynthesis PINUS yunnanensis Tomicus MINOR Tomicus yunnanensis
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The effect of maternal BDE-209 exposure on offsping's expression of MAP-1B and S100 in hippocampus of the rats
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作者 Yu Lin Su Tao +1 位作者 Chen Shengqiang Chen Dunjin 《现代妇产科进展》 CSCD 北大核心 2008年第12期957-960,共4页
Objective:To study the effect of maternal BDE-209 (brominated Diphenyl Ethers-209)exposure on the expression of microtubule-associated protein-1b (map-1b) and S-100 in rat's hippocampus of the offspring by RT-PCR.... Objective:To study the effect of maternal BDE-209 (brominated Diphenyl Ethers-209)exposure on the expression of microtubule-associated protein-1b (map-1b) and S-100 in rat's hippocampus of the offspring by RT-PCR.Methods:Peanut oil suspensions of commercial deca-BDE was given in dose of 300 mg/(kg·d) by oral gavage throughout gestation and lactation in experimental group.The control group was administered only with the same capacity of peanut oil at the same time.The expression of MAP-1B in the hippocampus of the offspring's rats were tested when the pups were newborn,7days,14 days,21days and 45days old respectively by means of RT-PCR.Result:MAP-1B protein showed a statistically significantly lower concentration in the groups 14 days,21days,45days than that of the control groups.The expression of S-100 in the group which received with deca-BDE by RT-PCR showed higher than that of control groups.But only the 45days groups had significant difference of expression of MAP-1B protein compared with the control groups(P<0.05).Conclusions:Maternal BDE-209 exposure during the period of pregnancy will diminish the expression of map-1b protein in hippocampus of offspring's rats. 展开更多
关键词 产妇 溴化二苯醚 哺乳期 药物分析
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THE UNSTABLE MODES OF NATURAL CONVECTION BOUNDARY LAYER
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作者 陶建军 庄逢甘 颜大椿 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2000年第3期217-222,共6页
The instability of natural convection boundary layer around a vertical heated flat plate is analyzed theoretically in this paper. The results illustrate that the 'loop' in the neutral curve is not a real loop ... The instability of natural convection boundary layer around a vertical heated flat plate is analyzed theoretically in this paper. The results illustrate that the 'loop' in the neutral curve is not a real loop but a twist of the curve in the frequency-wave number-Grashof number space, and there is only one unstable mode at small Prandtl numbers. Specially, when the Prandtl number is large enough two unstable modes will be found in the 'loop' region. Along the amplifying surface intersection the two unstable modes have the same Grashof number, wave number and frequency but different amplifying rates. Their instability characteristics are analyzed and the criterion for determining the existence of the multi-unstable modes is also discussed. 展开更多
关键词 INSTABILITY natural convection boundary layer amplifying surface
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HIGH PRESSURE SYNTHESIS OF HIGH T_(c)A15 Nb_(3)Si
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作者 WANG Yaoji WANG Wenkui +1 位作者 HE Shouan H.Iwasaki 《Chinese Physics Letters》 SCIE CAS 1987年第1期44-46,共3页
The A15 Nb_(3)Si with a smaller lattice parameter(a=0.5093nm)has been synthesized from the amorphous Nb_(77)Si_(23) alloy under high pressure by using Bridgman anvils apparatus.Superconductivity measurements shoued th... The A15 Nb_(3)Si with a smaller lattice parameter(a=0.5093nm)has been synthesized from the amorphous Nb_(77)Si_(23) alloy under high pressure by using Bridgman anvils apparatus.Superconductivity measurements shoued that the A15 phase produced from Nb_(77)Si_(23) has the highest T_(c)(19.1K)among all that can be obtained from Nb-Si alloys. 展开更多
关键词 alloys. ALLOY (3)
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