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Advances in Small RNAs and Sexual Reproduction in Plants
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作者 王俊 何桥 +5 位作者 汪卫星 向素琼 孙海艳 李晓林 梁国鲁 郭启高 《Agricultural Science & Technology》 CAS 2013年第2期211-214,229,共5页
Small RNAs are non-coding RNA molecules with 20-30 nucleotides (nt) in length that mainly play regulatory roles in gene expression at the post-transcription level by directly cutting target mRNA or inhibiting its tr... Small RNAs are non-coding RNA molecules with 20-30 nucleotides (nt) in length that mainly play regulatory roles in gene expression at the post-transcription level by directly cutting target mRNA or inhibiting its translation. Small RNAs play regulatory roles in the growth and development process of plants at the core of gene regulatory networks, which has been widely studied and confirmed in sporophyte generation of plants. However, few researches have been conducted on small RNAs and gametophyte generation. It is reported that small RNAs play important roles in floral organ development, gametogenesis, fertilization, and early zygotic development of plants. In addition, various small RNAs also play roles in controlling genetic integrity, cell differentiation and functions during the sexual reproduction process of plants. However, most of the specific functions of small RNAs in the sexual reproduction process are unknown yet. This study mainly aimed to introduce small RNAs in plants, summarize the latest advances in researches of small RNAs and plant sexual reproduction, and make prospect on its future. 展开更多
关键词 Small RNA Sexual reproduction Floral organ development GAMETOGENESIS FERTILIZATION Early zygotic development
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Biosorption of Cd (Ⅱ) and Pb (Ⅱ) Ions by Aqueous Solutions of Novel Alkalophillic Streptomyces VITSVK5 spp. Biomass 被引量:6
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作者 Kumar Saurav Krishnan Kannabiran 《Journal of Ocean University of China》 SCIE CAS 2011年第1期61-66,共6页
Discharge of heavy metals from metal processing industries is known to have adverse effects on the environment.Bio-sorption of heavy metals by metabolically inactive biomass of microbial organisms is an innovative and... Discharge of heavy metals from metal processing industries is known to have adverse effects on the environment.Bio-sorption of heavy metals by metabolically inactive biomass of microbial organisms is an innovative and alternative technology for removal of these pollutants from aqueous solution.The search of marine actinobacteria with potential heavy metal biosorption ability resulted in the identification of a novel alkalophilic Streptomyces VITSVK5 species.The biosorption property of Streptomyces VITSVK5 spp.was investigated by absorbing heavy metals Cadmium (Cd) and Lead (Pb).Physiochemical characteristics and trace metal concentration analysis of the backwater showed the concentrations of different metals were lead 13±2.1 μg L-1,cadmium 3.1±0.3μg L-1,zinc 8.4±2.6μg L-1 and copper 0.3±0.1μg L-1,whereas mercury was well below the detection limit.The effect of pH and biomass dosage on removal efficiency of heavy metal ions was also investigated.The optimum pH for maximal biosorption was 4.0 for Cd (II) and 5.0 for Pb (II) with 41% and 84% biosorption respectively.The biosorbent dosage was optimized as 3 g L-1 for both the trace metals.Fourier transform infrared absorption spectrum results indicated the chemical interactions of hydrogen atoms in carboxyl (–COOH),hydroxyl (–CHOH) and amine (–NH2) groups of biomass with the metal ions.This could be mainly involved in the biosorption of Cd (II) and Pb (II) onto Streptomyces VITSVK5 spp.The results of our study revealed Streptomyces metabolites could be used to develop a biosorbent for adsorbing metal ions from aqueous environments. 展开更多
关键词 heavy metals BIOSORPTION Streptomyces VITSVK5 spp pH biomass dosage
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Temperature Effect on the Life History of Three Types of Brachionus calyciflorus Females 被引量:4
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作者 席贻龙 黄祥飞 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2004年第2期192-197,共6页
The effect of temperature on the life history characteristics of amictic females (AF), unfertilized mictic females (UMF) and fertilized mictic females (FMF) in Brachionus calyciflorus was studied with replicated indiv... The effect of temperature on the life history characteristics of amictic females (AF), unfertilized mictic females (UMF) and fertilized mictic females (FMF) in Brachionus calyciflorus was studied with replicated individual cultures at 20℃,25℃ and 30℃, and with algae Scenedesmus obliquus for their food. There were highly significant effects of both temperature and female type, independently and interactively, on the duration of juvenile and post-reproduction periods, and the number of eggs produced by the rotifer per life cycle. Among all the temperature-female type combinations, all the juvenile periods of FMF, and the post-reproduction periods of UMF and FMF at 20℃, were the longest, and the number of eggs produced by an UMF at 30℃ was the highest. There were highly significant effects of both temperature and female type on the duration of the reproduction period, but no clear correlation was observed between temperature and female type. The reproduction period of AF was longer than that of UMF and FMF. Only temperature influenced significantly the mean life-span of the three types of females. The duration of juvenile, reproduction and post-reproduction periods as well as the life-span of the three types of females were all reduced very significantly with rise of temperature, but the rates of reduction varied with female type. Among the three types of females, the number of eggs produced per life cycle by an UMF was the highest, and that of a FMF was the lowest. A significant relationship between the number of eggs produced per life cycle and temperature was observed only in the UMF. 展开更多
关键词 Brachionus calyciflorus ROTIFER life history TEMPERATURE female type
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Recent Researches of Bioactive Metabolites in Marine Organisms-associated Microorganisms
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作者 GUQianqun LUJia +4 位作者 CUIChengbin ZHUTianjiao FANGYuchun LIUHongbing ZHUWeiming 《Journal of Ocean University of China》 SCIE CAS 2004年第2期150-156,共7页
Recent researches have shown that some compounds isolated from marine organisms have striking structural similarities with the metabolites from known microorganisms. It is inferred from the researches that the symbiot... Recent researches have shown that some compounds isolated from marine organisms have striking structural similarities with the metabolites from known microorganisms. It is inferred from the researches that the symbiotic or associated marine microorganisms may be the true sources of those compounds or at least involved in the biosynthesizing process. This view has been further evidenced by the researches for many sponges and sponge-associated microorganisms. Importantly, growing evidence has highlighted that the symbiotic or associated marine microorganisms live in the microenvironment within the hosts, and they also produce secondary metabolites which are new and original in structure and unique in activity. All these suggest that the microorganisms associated with marine organisms are the sources with very high potential to be new natural bioactive agents. This article reviews briefly the research advances in the study of new bioactive metabolites from marine organisms-associated microorganisms since 2000. 展开更多
关键词 marine microorganism SYMBIONT bioactive METABOLITE
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Operationalizing physical literacy: The potential of active video games 被引量:4
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作者 Haichun Sun 《Journal of Sport and Health Science》 SCIE 2015年第2期145-149,共5页
The core idea of physical literacy is a mind-body integrated, holistic approach to physical activity. A physically literate individual is expected to be cognitively knowledgeable, physically competent, and mentally mo... The core idea of physical literacy is a mind-body integrated, holistic approach to physical activity. A physically literate individual is expected to be cognitively knowledgeable, physically competent, and mentally motivated for a physically active life throughout the lifespan. The advancement of technology in recent years, especially those in active video games(AVGs), seems to have allowed the mind-body integrated physical activity accessible to children at all ages. This article reviews findings from research and critique research on AVGs in light with the theoretical and pedagogical tenets of physical literacy and, on the basis of the review, elaborates the potential that AVGs could contribute to enhancing children's physical literacy. 展开更多
关键词 Exergaming MOTIVATION Motor skill learning Physical activity Physical education
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A Model Describing the Time Course and Variability in Toxicity of Hydrophobic Chemicals to Aquatic Organisms-Toxicity of chlorinated benzenes to marine algae
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作者 WANG Xiulin SHAN Baotian +3 位作者 GE Ming ZHANG Lei ZHU Chenjian HAN Xiurong 《Journal of Ocean University of Qingdao》 2002年第1期71-79,共9页
The growth of Chlorella marine, Nannochloris oculate, Pyramimonaos sp., Platymonas subcordiformis and Phaeodactylum tricornutum exposed to chlorobenzene, 1,2-dichlorobenzene, 1,2,3,4-tetrachlorobenzene and pentach-lor... The growth of Chlorella marine, Nannochloris oculate, Pyramimonaos sp., Platymonas subcordiformis and Phaeodactylum tricornutum exposed to chlorobenzene, 1,2-dichlorobenzene, 1,2,3,4-tetrachlorobenzene and pentach-lorobenzene was tested. The Boltzman equation was used to describe organism growth. The time course for uptake of hydrophobic organic chemicals (HOCs) by aquatic organisms was expressed by incorporating growth and, if desired, the effect of metabolism into the HOC bioconcentration process. The probability of any given concentration of HOCs in the organisms causing a specified toxic endpoint was expressed with a modified Weibull distribution function. The combined bioconcentration and probability equations were tested with data for time course of incubation of algae exposed to chlorinated benzenes (CBs). A set of parameters, including the uptake rate constant k 1, the elimination rate constant k 2 and thereafter the bioconcentration factor on a dry weight basis, BCF D, the critical HOC concentration in the organism resulting in a specified toxic endpoint, C* A, and the spread factor, S, could be obtained by fitting only experimental data for percent growth inhibition(%)-time-CB exposure concentration. The average coefficients of variation within CBs were 15.2% for BCF D, 21.0% for k 1, 18.3% for k 2, 8.1% for C* A and 9.7% for S. The variability in toxicity (such as EC 10, EC 50, EC 90) derived from the model equations agreed well with those experimentally observed. 展开更多
关键词 TOXICITY BIOCONCENTRATION MODEL chlorinated benzenes ALGAE
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Impact of Deficient Nutrition on Health Condition of Persons with Dementia
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作者 Velija Katica Nadzida Mlaco +1 位作者 Amela Katica Jasmin Katica 《Journal of Environmental Science and Engineering(B)》 2017年第11期582-588,共7页
Dementia is a loss of mental ability (ability to think, remember and make logical conclusions) which, in principle affects normal everyday life of a person. Dementia is not a disease but a group of symptoms that may... Dementia is a loss of mental ability (ability to think, remember and make logical conclusions) which, in principle affects normal everyday life of a person. Dementia is not a disease but a group of symptoms that may cause different diseases. Symptoms include change of behaviour, character and unexpected changes in the mood. Poor quality of nutrition affects significantly the intensity of dementia. Balanced diet that meets healthy safety standards and requirements will satisfy the needs of an organism for vitamins and minerals and special attention should be given to intake of folic acid, vitamin B12 and minerals zinc and selenium. Intake of omega3 fatty acids is a source of fuel for blood vessels, particularly for the ones of the nervous tissues. 展开更多
关键词 Dementio NUTRITION war period.
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Numerical study on freezing-thawing phase change heat transfer in biological tissue embedded with two cryoprobes 被引量:1
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作者 赵芳 陈振乾 施明恒 《Journal of Central South University》 SCIE EI CAS 2009年第2期326-331,共6页
A two-dimensional model for freezing and thawing phase change heat transfer in biological tissue embedded with two cryoprobes was established.In this model,the blood vessels were considered as tree-like branched fract... A two-dimensional model for freezing and thawing phase change heat transfer in biological tissue embedded with two cryoprobes was established.In this model,the blood vessels were considered as tree-like branched fractal network,and the effective flow rate and effective thermal conductivity of blood were obtained by fractal method.The temperature distribution and ice crystal growth process in biological tissue embedded with two cryoprobes during freezing-thawing process were numerically simulated.The results show that the growth velocity of ice crystal in freezing process from 200 to 400 s is more rapid than that from 400 to 600 s. Thawing process of frozen tissue occurs in the regions around cryoprobes tips and tissue boundary simultaneously,and the phase interfaces are close to each other until ice crystal melts completely.The distance of two cryoprobes has a more profound effect on the temperature distribution in freezing process at 400 s than at 800 s. 展开更多
关键词 heat transfer FRACTURE phase change FREEZING thawing
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Production of Interleukin 2 like Growth Factor from the Mitogen Activated Peripheral Blood Lymphocytes of Indian Major Carp, Labeo rohita
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作者 G. R. Dash K. Pani Prasad S. P. Sen 《Journal of Agricultural Science and Technology(B)》 2011年第8期1184-1190,共7页
Optimum conditions for in vitro production of interleukin 2 (IL 2) like activity from the Peripheral blood lymphocytes (PBL) of an Indian major carp, Labeo rohita were studied. Culture supernatants were generated ... Optimum conditions for in vitro production of interleukin 2 (IL 2) like activity from the Peripheral blood lymphocytes (PBL) of an Indian major carp, Labeo rohita were studied. Culture supernatants were generated by culturing the PBL in RPMI-1640 media supplemented with Glutamine and 10% fetal bovine serum (FBS) and stimulating with two different mitogens: concanavalin A (Con A) and Phytohaemagglutinin (PHA) at different concentrations separately. Significantly (P 〈 0.01) higher proliferation response was obtained from the culture supematant stimulated with concanavalin A (Con A) at a concentration of 10 lag mLl. The effect of phorbol myristate acetate (PMA) was also studied by co-stimulating PBL with Con A and PHA separately and it was found to synergistically enhancing the stimulation index with Con A whereas the stimulation index remain unchanged with PHA. The Con A (10 μg mLl) stimulated PBL were also cultured at different cell density, incubation period and incubation temperature in order to optimize the in vitro L. rohita IL2 production. The IL2 like activity was studied by lymphocyte proliferation assay on 72 h Con A blasts using WST based assay technique. Significantly (P 〈 0.01) higher stimulation indices were obtained when the PBL were cultured at a cell density of 1 × 10^6 cells mL^-1 for 30-36 h at an incubation temperature of 30 ℃. The IL2 like activity was purified by DEAE-Sepharose anion exchange chromatography and recorded between 70-130 mM NaCI with peak activity at 110 Mm NaCI. The molecular weight of the factor responsible for IL2 like activity was found to be 15-17 KD. 展开更多
关键词 Interleukin 2 MITOGEN Labeo rohita lymphocytes.
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Metal‐organic framework‐derived multifunctional photocatalysts 被引量:3
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作者 Yaping Zhang Jixiang Xu +1 位作者 Jie Zhou Lei Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第4期971-1000,共30页
Metal‐organic framework(MOF)‐derived nanomaterials have attracted widespread attention,because the excellent features,such as high surface area,porosity and tunable properties are inherited from MOFs.Moreover,the de... Metal‐organic framework(MOF)‐derived nanomaterials have attracted widespread attention,because the excellent features,such as high surface area,porosity and tunable properties are inherited from MOFs.Moreover,the derivatives avoid the poor conductivity and stability of MOFs.MOF‐derived nanomaterials can easily be regulated by a specific selection of metal nodes and organic linkers,resulting in multifunctionality in photocatalysis.MOF derivatives can be used not only as semiconductor photocatalysts,but also as co‐catalysts for photocatalytic hydrogen evolution,CO_(2) reduction,pollutants degradation,etc.This review focuses on the multifunctional applications of MOF derivatives in the field of photocatalysis.The researches in recent years are analyzed and summarized from the aspects of preparation,modification and application of MOF derivatives.At the end of the review,the development and challenges of MOF derivatives applied in photocatalysis in the future are put forward,in order to provide more references for further research in this field and bring new inspiration. 展开更多
关键词 MOF‐derived nanomaterials Semiconductor photocatalyst COCATALYST H_(2)evolution CO_(2)reduction Pollution degradation
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Impact of Organic Vegetable Production System in Kiambu and Kajiado Counties of Kenya
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作者 Samuel Kiruku Ndungu Ibrahim Macharia +1 位作者 Ruth Kahuthia-Gathu Raphael Githaiga Wahome 《Journal of Environmental Science and Engineering(A)》 2013年第4期256-266,共11页
Though there are many documented reasons that make farmers to adopt organic farming system, economic benefits present a major motivation. The study was conducted to evaluate the impact of organic production system on ... Though there are many documented reasons that make farmers to adopt organic farming system, economic benefits present a major motivation. The study was conducted to evaluate the impact of organic production system on profitability of smallholder vegetable production systems in the two counties so as to appraise its contribution to improvement of rural livelihoods. The study collected data on costs and returns for a sample of 208 smallholder vegetable farmers who were composed of 78 organic and 130 conventional farmers. Impact of organic production system was evaluated using propensity score matching technique. Organic vegetable production system was found to have a positive significant impact of increasing farm gross margin by US$0.58 representing 89.5% among smallholder producers in Kiambu and Kajiado Counties of Kenya. The study recommended promotion of organic production system as a tool that can be used to improve livelihoods especially in the rural areas. 展开更多
关键词 ORGANIC PROFITABILITY IMPACT organic vegetables smallholder production systems.
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The simulation of electrostatic coupling intra-body communication based on the finite-element method
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作者 Song Yong Zhang Kai Yang Guang Zhu Kang Hao Qun 《Engineering Sciences》 EI 2011年第1期30-34,共5页
In this paper, investigation has been done in the computer simulation of the electrostatic coupling IBC by using the developed finite-element models, in which a.the incidence and reflection of electronic signal in the... In this paper, investigation has been done in the computer simulation of the electrostatic coupling IBC by using the developed finite-element models, in which a.the incidence and reflection of electronic signal in the upper arm model were analyzed by using the theory of electromagnetic wave;b.the finite-element models of electrostatic coupling IBC were developed by using the electromagnetic analysis package of ANSYS software;c.the signal attenuation of electrostatic coupling IBC were simulated under the conditions of different signal frequencies, electrodes directions, electrodes sizes and transmission distances. Finally, some important conclusions are deduced on the basis of simulation results. 展开更多
关键词 Intra-body Communication electrostatic coupling FINITE-ELEMENT personal area network
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Relative Effectiveness of Ultraviolet Light Irradiation and Chlorination against Indigenous Bacteriophage and Bacteria in Primary Treated Wastewater
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作者 Jatuwat Sangsanont Kumiko Oguma Hiroyuki Katayama 《Journal of Environmental Science and Engineering(B)》 2012年第8期1003-1009,共7页
The effectiveness of chlorine and ultraviolet light at inactivating indigenous microbes in primary treated wastewater was examined in this study. The inactivation rates for somatic colipahge and F-specific bacteriopha... The effectiveness of chlorine and ultraviolet light at inactivating indigenous microbes in primary treated wastewater was examined in this study. The inactivation rates for somatic colipahge and F-specific bacteriophage were less than 2.5 log and 1 log, respectively, at either free chlorine doses of 6, 15 mg/L and 30 mg/L after 30 minutes contact time. However, E. coli and total coliforms were susceptible to chlorination and inactivated more than 4 log within first 15 minutes of contact time at any chlorine dosage tested. In contrast, the inactivation of bacteriophage was increased when increasing UV fluence. At the same disinfection effectiveness against E. coli, UV disinfection was more effective than chlorination against F-specific bacteriophages. 展开更多
关键词 CHLORINATION UV irradiation indigenous bacteriophage indigenous bacteria wastewater.
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In Vitro Hyphal Growth Inhibition of Plant Pathogenic Fungi by Corrigiola Telephiifolia Extracts
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作者 H. Lakmichi F.Z. Bakhtaoui +1 位作者 K. Loutfi C.A. Gadhi 《Journal of Environmental Science and Engineering》 2010年第5期42-48,共7页
The sugar beet root rot and Bayoud disease, respectively caused by Sclerotium rolfsii and Fusarium oxysporum albedinis, are major agricultural problems in Morocco, affecting its economical and social conditions. As of... The sugar beet root rot and Bayoud disease, respectively caused by Sclerotium rolfsii and Fusarium oxysporum albedinis, are major agricultural problems in Morocco, affecting its economical and social conditions. As of now, no effective control method of these phytopathogens is available. Therefore the search for new efficient and ecologically undamaging fungicides was essential. The present study reports the antifungal activity of five organic extracts of Corrigiola telephiifolia Pourr., a Moroccan medicinal plant, against these fungi using mycelial growth inhibition assays (in vitro). The extracts concentration varied from 0.01 to 1 mg.mlt. Also, preliminary information on the chemical composition of the extracts is included. The results showed a difference in sensitivity of both fungi toward the plant extracts. The mycelia growth of Sclerotium rolfsii was concentration and time-dependant. It was markedly inhibited by the polar extracts especially at high dose (p〈 0.001). While Fusarium oxysporum f. sp. albedinis was much less sensitive. 展开更多
关键词 BIOFUNGICIDE corrigiola telephiifolia fitsarium oxysporum sclerotium rolfsii kinetic study.
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Are Polymers Toxic? Case Study: Environmental Impact of a Biopolymer
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作者 Giovanna Mercado Martha Dominguez +1 位作者 Israel Herrera Rosa Maria Melgoza 《Journal of Environmental Science and Engineering(B)》 2017年第3期121-126,共6页
In this paper, the analysis of the environmental impacts of a biopolymer based on starch is presented. These impacts were calculated from a cradle to gate LCA (Life Cycle Assessment), based on UNEEN ISO 14040:2006 ... In this paper, the analysis of the environmental impacts of a biopolymer based on starch is presented. These impacts were calculated from a cradle to gate LCA (Life Cycle Assessment), based on UNEEN ISO 14040:2006 and UNEEN ISO 14044, using as functional unit 1 kg of produced biomaterial. The impact categories analyzed were global wanning, ozone depletion, acidification and eutrophication. The results indicate that the electricity causes the highest impacts in the global warming and ozone depletion categories, but compared to synthetic polymers, the emissions are low. Finally, in the case of eutrophication, the impacts are similar to other biopolymers but higher in comparison with petroleum-based polymers like HDPE (High Density Polyethylene), LDPE (Low Density Polyethylene), PP (Polypropylene), PS (Polystyrene) and PET (Polyethylene Terephthalate). 展开更多
关键词 Polymer BIOPOLYMER LCA environmental impacts.
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日语セズニイル·セズニアル的动态研究及语用原则的选择 被引量:1
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作者 黄文溥 《外国语言文学》 2009年第2期73-78,共6页
语言形式的使用实态需要在历时动态和共时动态的研究中得到充分的把握和解释。(1)日语セズニイル·セズニアル被以往的静态研究所忽视的共时特征可以从历时动态的考察中得到解释。(2)调查显示,日语セズニイル主语主要限于有生体,セ... 语言形式的使用实态需要在历时动态和共时动态的研究中得到充分的把握和解释。(1)日语セズニイル·セズニアル被以往的静态研究所忽视的共时特征可以从历时动态的考察中得到解释。(2)调查显示,日语セズニイル主语主要限于有生体,セズニアル在使用上也受限制。两种限制性质相同,可以在共时动态的研究框架中作出统一的说明:它们都是在使用上受制于经济性和明晰性的语用原则。个别人偏爱使用这两个形式表示无生命的否定的状态,这是以牺牲经济原则和明晰原则为代价,受表达力原则驱使而出现的结果。 展开更多
关键词 动态研究 语用原则 有生体 无生命
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Modificaomics:deciphering the functions of biomolecule modifications 被引量:3
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作者 Ting Liu Cheng-Jie Ma +1 位作者 Bi-Feng Yuan Yu-Qi Feng 《Science China Chemistry》 SCIE EI CAS CSCD 2018年第4期381-392,共12页
The spatiotemporal expression of genes is sophisticatedly controlled through three main layers: transcriptional, translational and post-translational. Now increasing chemical modifications are discovered on genomic DN... The spatiotemporal expression of genes is sophisticatedly controlled through three main layers: transcriptional, translational and post-translational. Now increasing chemical modifications are discovered on genomic DNA, RNA and proteins. These modifications are recognized as additional layer of regulatory mechanisms in controlling gene expression that defines cell status. So far,more than 150 chemical modifications are identified in nucleic acids,and more than 400 discrete types of modifications are identified in proteins. How these modifications are interpreted are fundamental questions to our understanding of living organisms. The omics sciences of systems biology, including genomics, transcriptomics, proteomics, and metabolomics, have been in existence for decades. Due to the large numbers of modifications occurring in DNA, RNA and proteins with regulatory roles, we propose the modificaomics from the words of modification and omics. Modificaomics mainly refers to the comprehensive study of the modifications on DNA, RNA and proteins. In this review, we conceive modificaomics by introducing the discovered modifications in DNA, RNA and proteins as well as summarizing their biological functions. We hope the proposed modificaomics can provide a whole picture of modifications of these biopolymers and simulate the study of the functions of the modifications on DNA, RNA and proteins. 展开更多
关键词 modificaomies DNA modifications RNA modifications protein modifications FUNCTIONS
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Total chemical and semisynthetic approaches for the preparation of ubiquitinated proteins and their applications 被引量:6
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作者 Xiaobao Bi Kalyan Kumar Pasunooti Chuan-Fa Liu 《Science China Chemistry》 SCIE EI CAS CSCD 2018年第3期251-265,共15页
Protein ubiquitination is an important post-translational modification(PTM) in eukaryotic organisms that regulates a variety of cellular processes, such as protein degradation, signal transduction, apoptosis, and DNA ... Protein ubiquitination is an important post-translational modification(PTM) in eukaryotic organisms that regulates a variety of cellular processes, such as protein degradation, signal transduction, apoptosis, and DNA damage tolerance. To decipher mechanistically the diverse biological functions of ubiquitination, homogeneous ubiquitinated proteins are greatly needed.Although direct isolation from cell source and in vitro enzymatic methods can be used to produce such proteins, these methods often suffer from problems of low yield or heterogeneous products. Comparably, total chemical and semisynthetic approaches offer good alternatives to produce the ubiquitinated proteins with high purity and selectivity. This review summarizes the recent developments of protein ubiquitination strategies and the use of the synthesized proteins to help garner structural and functional insight into the inner workings of the ubiquitin system. 展开更多
关键词 UBIQUITINATION native chemical ligation deubiquitinases protein synthesis
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Large-scale fabrication of field-effect transistors based on solution-grown organic single crystals 被引量:3
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作者 Shuang Liu Jia-Ke Wu +4 位作者 Cong-Cheng Fan Guo-Biao Xue Hong-Zheng Chen Huolin L. Xin Han-Ying Li 《Science Bulletin》 SCIE EI CAS CSCD 2015年第12期1122-1127,I0003,共7页
A simple solution processing method was de- veloped to grow large-scale well-aligned single crystals in- cluding 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS- pentacene), anthracene, tetracene, perylene, C6o ... A simple solution processing method was de- veloped to grow large-scale well-aligned single crystals in- cluding 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS- pentacene), anthracene, tetracene, perylene, C6o and tetra- cyanoquinodimethane. As pinned by a solid needle, a droplet of semiconductor solution dried into single-crystal arrays on a 1 cm×2 cm substrate. TIPS-pentacene was used to demonstrate the fabrication of hundreds of field- effect transistors (FETs) with the hole mobility as high as 6.46 cm^2 V^-1.s^-1. As such, this work provides a high- throughput, yet efficient approach for statistical examination on the FET performance of organic single crystals. 展开更多
关键词 Organic single-crystal transistors Large scale High mobility Solution process
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A novel purification technique for noble gas isotope analyses of authigenic minerals 被引量:2
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作者 HE LiYan QIU HuaNing +3 位作者 SHI HeSheng ZHU JunZhang BAI XiuJuan YUN JianBing 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第1期111-117,共7页
Noble and active gases are released from geological samples during gas extraction for noble gas isotope analyses. The active gases should be removed before inletting to mass spectrometers for the analyses. The normal ... Noble and active gases are released from geological samples during gas extraction for noble gas isotope analyses. The active gases should be removed before inletting to mass spectrometers for the analyses. The normal noble gas preparation systems can clean up most geological samples. However, authigenic minerals from sedimentary rocks in oil/gas fields contain organic matter, which cannot be cleaned up by the normal preparation systems and thus influence the noble gas analyses. We introduce a novel gas purification system (PRC patent No. ZL201320117751.2), which includes several reversible purification pumps with different absorbing and degassing temperatures. It can well clean up water steam, carbon dioxide and organic gas- es. Mica minerals are often used for 40Ar/39Ar dating. A muscovite sample (2082MS) which could not be cleaned up by the normal preparation system with two SAES NP10 getters, becomes the test sample for a comparative experiment in this study. The experiment is assigned into 4 sections with the organic gas removal system (OGRS) "Closed/Opened" in turn. When the OGRS is closed only with two NP10 getters for purification, the 40At intensities increase in curves with inlet time because of impurities, the 40Ar/39Ar dating results yield age errors about +2%-±1% (20-). When the OGRS is opened for purification, in contrast, the 40Ar intensities decrease linearly with inlet time. This indicates that the gases have been cleaned up effectively, and the 40Ar/39Ar results yield ages with errors in ±0.4%. The OGRS is very helpful to obtain high-quality analysis data. 展开更多
关键词 40Ar/39Ar dating Gas purification technique Organic impurity Noble gas
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