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Preparation of BCEC-Astrocyte Co-culturing Membrane Plate Insert 被引量:1
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作者 赵康峰 王琪 +2 位作者 蒲小平 杨秀伟 朱玉真 《Journal of Chinese Pharmaceutical Sciences》 CAS 2004年第4期276-281,共6页
To prepare a hand-made micropore membrane culture plate insert forco-culture. Methods The plate insert was made using plastic centrifuge tube and micropore membrane.After seeding brain capillary endothelial cells (BCE... To prepare a hand-made micropore membrane culture plate insert forco-culture. Methods The plate insert was made using plastic centrifuge tube and micropore membrane.After seeding brain capillary endothelial cells (BCECs) on it (under the effect ofastrocyte-conditioned medium), the plate insert was assessed by analysis of trans-endothelialelectrical resistance (TEER). Results The plate insert has a stability of at least 15 d underculture condition. TEER increased significantly under co-culture condition from (66.1 +- 13.3)Ωcm^2 to (182.2 +- 6.7) Ωcm^2. Conclusion This micropore membrane culture plate insert can beeasily made, on which BCEC culture can be successfully performed. Moreover, it is adjustable andrecyclable. It follows that the plate insert is a useful tool for co-culture and the relatedresearch fields. 展开更多
关键词 blood-brain barrier culture plate insert brain capillary endothelial cell ASTROCYTE trans-endothelial electronic resistance
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A Multi-Generation Schmakeria poplesia Culturing System for Use in Ecotoxicological Study 被引量:1
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作者 HUANG Ying ZHU Liyan QIU Xuchun QI Benjin ZHANG Tianwen 《Journal of Ocean University of China》 SCIE CAS 2009年第1期30-34,共5页
Crustacean zooplankton form the keystone link between primary producers and fish stocks in marine and estuary, ecosystems. We have established a multi-generation cultivation system for zooplankton ruth which future ex... Crustacean zooplankton form the keystone link between primary producers and fish stocks in marine and estuary, ecosystems. We have established a multi-generation cultivation system for zooplankton ruth which future experiments on the biological effects of pollutants in marine and estuary environments can be better performed. A population of calanoid copepod, Sehmakeria poplesia, was collected in December 2003 and maintained in a static system through all stages (eggs to adults). The population ex- hinted an average developmental time of 13.6 d in conditions corresponding to the natural environment (water temperature 20~C salinity 15). A series of experiments were performed to examine copepod egg production and hatching success as functions of food type and feeding concentration. Results in our study showed that Isoehrysis galbana was more favored for the reproduction of cope- pods than Phaeodactylum tricornutum, and 10xl0%ellsmL-1 was the most practical algae concentration. We have demonstrated that the Schmakeria poplesia population can be maintained in the laboratory through multiple generations. In addition, methods to control egg production through changes in food concentration have been established, making it feasible to control the start date of exposure experiments or the timing of the collection of oftspring to initiate a new generation. 展开更多
关键词 Schmakeria poplesia culturing egg production development toxic pollutants
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Study on Culturing Prunus salicina cv.Zaoshi Embryos
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作者 余小玲 何业华 +2 位作者 韩景忠 谢志亮 彭兵 《Agricultural Science & Technology》 CAS 2010年第4期80-82,166,共4页
[Objective]The aim was to study the effective factors on culturing Prunus salicina cv.Zaoshi embryos in vitro.[Method]Different age,culture medium and GA3 which affected culturing of prumssalicina embryos were discuss... [Objective]The aim was to study the effective factors on culturing Prunus salicina cv.Zaoshi embryos in vitro.[Method]Different age,culture medium and GA3 which affected culturing of prumssalicina embryos were discussed.[Result]The result showed that on the part of 26-41 d,after the blooming period,the embryos remained tiny and retained endosperms and showed no signs of change after having cultured for three generations.On the part of 48 d,after the blooming period,the endosperms had disappeared,the embryos kept growing until they filled the seed cavity;when they were planted on the MS culture medium,their survival rate reached 77%,in its first generation,the response of embryos was discernible.On the part of 65 d,after the blooming period,4.5% of their embryos grew into shoots on the MS culture medium;with the age of embryos growing,the survival rate of shoots increased until it reached 26% when the fruits went into ripeness;the embryos produced calli in their first generation of culturing.On the part of 65-83 d,after the blooming period,the embryos produced calli through more than 2-3 generations.On the part of 88 d,after the blooming period,the survival rate of shoots on the WPM culturing base doubled compared with that on the MS culturing base;on the same culture medium,the embryos were inhibited from growing into shoots when BA,KT or 2,4-D was added on to the culture medium.The survival rate of shoots was increased remarkably when the seeds were treated in 1 000 mg/L GA3.[Conclusion] This study provided experimental basis for the establishment of Prunus salicina cv.Zaoshi,embryos rescue techniques and cross breading. 展开更多
关键词 Prunus salicina cv.Zaoshi Embryos Culture in vitro Age of embryo
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Optimization of IBRS-2 Cells Culturing Conditions for Cultivation of Porcine Parvovirus N Strain Using Roller Bottle
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作者 卢冰霞 何颖 +10 位作者 赵武 梁家幸 段群棚 蒋冬福 卢敬专 闭炳芬 周英宁 秦毅斌 李斌 苏乾莲 陈忠伟 《Agricultural Science & Technology》 CAS 2017年第5期839-842,共4页
The aim was to optimize the roller bottle culture system of IBRS-2 cells for cultivation of porcine parvovirus (PPV) N strain using a four-factor three-level or- thogonal test (cell culture medium pH value: 7.0, 7... The aim was to optimize the roller bottle culture system of IBRS-2 cells for cultivation of porcine parvovirus (PPV) N strain using a four-factor three-level or- thogonal test (cell culture medium pH value: 7.0, 7.2 and 7.4; inoculation time: 0, 24 and 48 h; inoculation dose: 0.10%, 1.00% and 10.00%; harvest time: 48, 72 and 96 h). The results showed that the optimal conditions were as follows: cell culture medium pH value of 7.2, synchronous inoculation, inoculation dose of 0.10% and culture time of 96 h. Among the four factors, culture time was the most important factor affectina the virulence titer of PPV N strain. 展开更多
关键词 Porcine parvovirus (PPV) Roller bottle culture OPTIMIZATION Orthogonal test
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Alginate Matrix of MDA-MB-231 Breast Cancer Cell 3D Culturing Alters CD44 and CD24 mRNA Levels and Induces ALDH1 Expression
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作者 Layane Duarte e Souza Elisa Raquel Anastacio Ferraz +3 位作者 Isis Soares Salviano Adenilson Souza da Fonseca Israel Felzenzswalb Andre Luiz Mencalha 《Journal of Life Sciences》 2017年第5期219-227,共9页
CSCs (Cancer stem cells) have been involved in tumor resistance, metastasis and recurrence. In breast cancer, tumor cells are characterized by CD44+, CD24-/low and ALDH 1 expression represents a subpopulation of BC... CSCs (Cancer stem cells) have been involved in tumor resistance, metastasis and recurrence. In breast cancer, tumor cells are characterized by CD44+, CD24-/low and ALDH 1 expression represents a subpopulation of BCSC (breast cancer stem cell). Several three-dimensional (3D) in vitro culturing cancer cells have been used to stimulate BCSC phenotype. The present study aimed to evaluate 3D cell culture in alginate matrix and the CD44, CD24 and ALDH1 mRNA levels of BCSC markers. The 3D culture was performed using MDA-MB-231 breast cancer cell line on alginate matrix 1.2% in RPMI medium. Expression of BCSC markers was evaluated by Real Time PCR (Polymerase Chain Reaction) comparing 3D to 2D culture. The 3D cultures increase of CD44 and CD24 mRNA levels and induce ALDH1 expression comparing to 2D culture. The data suggest that 3D alginate matrix alters the mRNA levels of genes involved in the phenotypic characteristics of BCSC. 展开更多
关键词 3D alginate culture CD44 CD24 ALDH1 breast cancer.
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中国古代槟榔文化的接受与传播
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作者 冯青 《农业考古》 北大核心 2024年第4期195-201,共7页
作为舶来品的槟榔,在饮食、医药、赋税等方面扮演过重要的角色,具有丰厚的历史文化。梳理文献发现,两汉三国时期,槟榔视作“奇草异木”记载在各种《异物志》中,开始被接受;南北朝时期,槟榔是贵族士宦的“奢侈品”,唐代受佛教平等思想影... 作为舶来品的槟榔,在饮食、医药、赋税等方面扮演过重要的角色,具有丰厚的历史文化。梳理文献发现,两汉三国时期,槟榔视作“奇草异木”记载在各种《异物志》中,开始被接受;南北朝时期,槟榔是贵族士宦的“奢侈品”,唐代受佛教平等思想影响日渐向大众传播,宋代逐渐成为百姓家的“寻常物”。槟榔之所以能被接受与传播,并在海南用于婚俗,是因其本身的物质文化之外,还与其因贵异而用于重要的人际礼仪、文人墨客极力推崇渲染和赋予了槟榔君子品格等精神文化有着莫大的关系。 展开更多
关键词 betel nut culture imported product ACCEPTANCE DISSEMINATION
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Culturing the Segments of Bryopsis hypnoides Lamouroux Thalli Regenerated from Protoplast Aggregations 被引量:6
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作者 Guang-Ce Wang Cheng-Kui Tseng 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2006年第2期190-196,共7页
Bryopsis hypnoides Lamouroux was regenerated In vitro from the protoplasm squeezed out from wild algae and the regenerated Individuals had an advantage over Indlvlduala from the wild In terms of growth. Culturing of s... Bryopsis hypnoides Lamouroux was regenerated In vitro from the protoplasm squeezed out from wild algae and the regenerated Individuals had an advantage over Indlvlduala from the wild In terms of growth. Culturing of segments of thalll also showed that segments from the regenerated algae grew better than those from individuals from the wild. The segment that corresponds to a part of a cell, at least a part of the protoplasm, can develop Into a mature Individual, Including rhlzold and thallus, suggesting that a multlnucleate alga, such as B. hypnoides, Is different from higher plants, whose totlpotancy Is based on an Intact cell (or protoplasm). Further cultivation of mature Individuals from segments Indicated that the organelles In the thallus had two ways In which they could survive when the alga was on the decline: (Ⅰ) the organelles were transferred Into a ball with a gelatinous envelope through a formed pipe and the ball seemed to be capable of being propagated; and (Ⅱ) the organelles were aggregated In the thallus and then moved to the outside. An Interesting result Is that one organelle aggregation located outside the thallus germinated and developed Into a mature alga, although most organelle aggregations gradually lost vitality and died. The results of the present study reveal that the aggregation of organelles can regenerate a stronger organism than Individuals from the wild owing to the complete exchange of genetic material and may possibly enable organelles to survive in unfavorable surroundings. 展开更多
关键词 aggregation Bryopsis hypnoides culturing thallus segment development germination protoplast.
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Automatic Extraction Method of 3D Feature Guidelines for Complex Cultural Relic Surfaces Based on Point Cloud 被引量:1
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作者 GENG Yuxin ZHONG Ruofei +1 位作者 HUANG Yuqin SUN Haili 《Journal of Geodesy and Geoinformation Science》 CSCD 2024年第1期16-41,共26页
Cultural relics line graphic serves as a crucial form of traditional artifact information documentation,which is a simple and intuitive product with low cost of displaying compared with 3D models.Dimensionality reduct... Cultural relics line graphic serves as a crucial form of traditional artifact information documentation,which is a simple and intuitive product with low cost of displaying compared with 3D models.Dimensionality reduction is undoubtedly necessary for line drawings.However,most existing methods for artifact drawing rely on the principles of orthographic projection that always cannot avoid angle occlusion and data overlapping while the surface of cultural relics is complex.Therefore,conformal mapping was introduced as a dimensionality reduction way to compensate for the limitation of orthographic projection.Based on the given criteria for assessing surface complexity,this paper proposed a three-dimensional feature guideline extraction method for complex cultural relic surfaces.A 2D and 3D combined factor that measured the importance of points on describing surface features,vertex weight,was designed.Then the selection threshold for feature guideline extraction was determined based on the differences between vertex weight and shape index distributions.The feasibility and stability were verified through experiments conducted on real cultural relic surface data.Results demonstrated the ability of the method to address the challenges associated with the automatic generation of line drawings for complex surfaces.The extraction method and the obtained results will be useful for line graphic drawing,displaying and propaganda of cultural relics. 展开更多
关键词 point cloud conformal parameterization vertex weight surface mesh cultural relics feature extraction
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Natural Disaster Risk Monitoring for Immovable Cultural Relics Based on Digital Twin 被引量:1
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作者 LI Bolun DONG Youqiang +2 位作者 QIAO Yunfei HOU Miaole WEN Caihuan 《Journal of Geodesy and Geoinformation Science》 CSCD 2024年第1期90-104,共15页
Natural disaster risk monitoring is an important task for disaster prevention and reduction.In the case of immovable cultural relics,however,the feedback mechanism,risk factors,monitoring logic,and monitoring indicato... Natural disaster risk monitoring is an important task for disaster prevention and reduction.In the case of immovable cultural relics,however,the feedback mechanism,risk factors,monitoring logic,and monitoring indicators of natural disaster risk monitoring are complex.How to achieve intelligent perception and monitoring of natural disaster risk for immovable cultural relics has always been a focus and a challenge for researchers.Based on the analysis of the concepts and issues related to the natural disaster risk of immovable cultural relics,this paper proposes a framework for natural disaster risk monitoring for immovable cultural relics based on the digital twin.This framework focuses on risk monitoring,including the physical entities of natural disaster risk for immovable cultural relics,monitoring indicators,and virtual entity construction.A platform for monitoring the natural disaster risk of immovable cultural relics is proposed.Using the Puzhou Ancient City Site as a test bed,the proposed concept can be used for monitoring the natural disaster risk of immovable cultural relics at different scales. 展开更多
关键词 immovable cultural relics natural disaster risk digital twin risk monitoring
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Between the City and Images:An Analysis of Mainstream Media’s Paths of Constructing the Cultural Memory of a City:Taking Chengdu Radio and Television’s“Hi Chengdu”as an Example 被引量:1
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作者 Ding Ran Shi Lei 《Contemporary Social Sciences》 2024年第2期97-111,共15页
Mainstream media play a crucial role in constructing the cultural memory of a city.This study used 319 short videos released by“Hi Chengdu,”a new media product of Chengdu Radio and Television,as samples.Based on the... Mainstream media play a crucial role in constructing the cultural memory of a city.This study used 319 short videos released by“Hi Chengdu,”a new media product of Chengdu Radio and Television,as samples.Based on the grounded theory,a research framework encompassing“content,technology,and discourse”was established to explore the paths through which mainstream media construct the cultural memory.Regarding content,this paper emphasized temporal and spatial contexts and urban spaces,delving deep into the themes of the cultural memory and vehicles for it.In terms of technology,this paper discussed the practice of leveraging audio/visual-mode discourse to stitch together the impressions of a city and evoke emotional resonance to create a“flow”of memory.As for discourse,this paper looked at the performance of a communication ritual to frame concepts and shape urban identity.It is essential to break free from conventional thinking and leverage local culture as the primary driving force to further boost a city’s productivity,in order to excel in cultural communication. 展开更多
关键词 the cultural memory of a city short videos the grounded theory Chengdu Radio and Television “Hi Chengdu”
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跨文化视域下的雍古艺术——《成为艺术:探索跨文化范畴》评介
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作者 张鑫 《美育学刊》 2024年第5期I0005-I0005,共1页
澳大利亚人类学家霍华德·墨菲(Howard Morphy)的《成为艺术:探索跨文化范畴》(Becoming Art:Exploring Cross-culture Categories)一书以澳大利亚阿纳姆地区的雍古艺术为研究对象,从时间线上梳理了雍古艺术的历史发展脉络,并从人... 澳大利亚人类学家霍华德·墨菲(Howard Morphy)的《成为艺术:探索跨文化范畴》(Becoming Art:Exploring Cross-culture Categories)一书以澳大利亚阿纳姆地区的雍古艺术为研究对象,从时间线上梳理了雍古艺术的历史发展脉络,并从人类学的角度对雍古艺术的社会功能、文化内涵、审美形式等具体问题进行了阐释。在方法论上,因不满于阿尔弗雷德·盖尔(Alfred Gell)将审美因素排除在艺术人类学领域之外的做法,墨菲在其雍古艺术史研究中采取了语义学维度与美学维度相结合的路径,并坚持认为审美因素是艺术品与其他物品区别开来的关键因素。 展开更多
关键词 文化范畴 跨文化视域 culture 阿尔弗雷德 人类学领域 审美因素 美学维度 阿纳姆
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Anticancer Activity of Rice Callus Suspension Cultures from Aromatic Varieties and Metabolites Regulated in Treated Cancer Cell Lines
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作者 Anuradha KUMARI Wusirika RAMAKRISHNA 《Rice science》 SCIE CSCD 2024年第4期449-462,I0027-I0030,共18页
Tissue culture techniques were used to produce large amounts of bioactive compounds with medicinal potential, overcoming space and time constraints for cancer prevention. Rice callus suspension cultures(RCSC) and seed... Tissue culture techniques were used to produce large amounts of bioactive compounds with medicinal potential, overcoming space and time constraints for cancer prevention. Rice callus suspension cultures(RCSC) and seed extracts prepared from aromatic rice varieties were used to evaluate the cytotoxic impact on human colon and lung cancer cell lines, as well as a normal control cell line, using Taxol as a positive control. RCSC and seed extracts from two Indian aromatic rice varieties were applied at different concentrations to treat the cancer cell lines and normal lung fibroblasts over varying time intervals. Apoptosis was assessed in 1:5 dilutions of the A549 and HT-29 cell lines treated with RCSC for 72 h, using propidium iodide staining and flow cytometry. RCSC showed a more potent cytotoxic effect than seed extracts with minimal effect on the normal cell line, in contrast to Taxol. Confocal microscopy and flow cytometry further confirmed the apoptotic effect of RCSC. Gas chromatography-mass spectrometry-based metabolic profiling identified metabolites involved in cytotoxicity and highlighted altered pathways. RCSC is proposed as an alternative source for the development of novel anticancer drugs with reduced side effects. 展开更多
关键词 ANTICANCER CYTOTOXICITY metabolite profiling plant tissue culture rice callus suspension culture secondary metabolite
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Brain dysfunctions and neurotoxicity induced by psychostimulants in experimental models and humans:an overview of recent findings
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作者 Marcello Serra Nicola Simola +1 位作者 Alexia E.Pollack Giulia Costa 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第9期1908-1918,共11页
Preclinical and clinical studies indicate that psychostimulants,in addition to having abuse potential,may elicit brain dysfunctions and/or neurotoxic effects.Central toxicity induced by psychostimulants may pose serio... Preclinical and clinical studies indicate that psychostimulants,in addition to having abuse potential,may elicit brain dysfunctions and/or neurotoxic effects.Central toxicity induced by psychostimulants may pose serious health risks since the recreational use of these substances is on the rise among young people and adults.The present review provides an overview of recent research,conducted between 2018 and 2023,focusing on brain dysfunctions and neurotoxic effects elicited in experimental models and humans by amphetamine,cocaine,methamphetamine,3,4-methylenedioxymethamphetamine,methylphenidate,caffeine,and nicotine.Detailed elucidation of factors and mechanisms that underlie psychostimulant-induced brain dysfunction and neurotoxicity is crucial for understanding the acute and enduring noxious brain effects that may occur in individuals who use psychostimulants for recreational and/or therapeutic purposes. 展开更多
关键词 3 4-methylenedioxymethamphetamine AMPHETAMINE caffeine cell cultures cocaine METHAMPHETAMINE METHYLPHENIDATE NEUROTOXICITY nicotine
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Analysis of the Reform of Ideological and Political Education in College English Curriculum from the Perspective of“Cultural Confidence” 被引量:1
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作者 Hui Zhang 《Journal of Contemporary Educational Research》 2024年第2期117-122,共6页
With the rapid development of the education industry,higher requirements have been put forward for college English education and teaching,accelerating the pace of college English reform.Issues such as how to integrate... With the rapid development of the education industry,higher requirements have been put forward for college English education and teaching,accelerating the pace of college English reform.Issues such as how to integrate knowledge transmission,language expression skill improvement,cultural element extraction,and ideological and political education,and present the role of curriculum education function have attracted attention.In the era of informatization,college students’thinking has undergone certain changes and gradually developed towards diversification.Therefore,universities should start from the perspective of cultural confidence,extract valuable ideological and political elements,and explore effective tourism ideological and political teaching methods.While helping college students enhance their cultural confidence,it is also beneficial for them to better inherit traditional Chinese culture.This article conducts an in-depth exploration of ideological and political education in college English courses from the perspective of“cultural confidence”and uses scientific and effective measures to solve the problems encountered,aiming to provide valuable guidelines for relevant researchers. 展开更多
关键词 Cultural confidence College English teaching Course ideological and political education MEASURE
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Effects of Different Culture Conditions and Growth States on the Structure and Hemostatic Properties of Coscinodiscus sp.
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作者 HE Zheng LI Qinfeng +4 位作者 LIU Jinfeng HUI Guangyan FENG Chao CHENG Xiaojie CHEN Xiguang 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第4期1121-1134,共14页
As a renewable marine inorganic material,Coscinodiscus sp.has significant potential in the field of rapid hemostasis.However,the low yield of Coscinodiscus sp.seriously limits the application.In this study,two new cul... As a renewable marine inorganic material,Coscinodiscus sp.has significant potential in the field of rapid hemostasis.However,the low yield of Coscinodiscus sp.seriously limits the application.In this study,two new culture modes were adopted to increase the production of Coscinodiscus sp.,the effect of changes in culture conditions and growth status on the hemostatic activity of diatoms was detected.To prevent Coscinodiscus sp.from sinking in culture,the suspension culture mode was realized by adding0.5%agar.The semi-continuous high nutrient concentration culture mode increased the cell density of Coscinodiscus sp.to 11000cells mL^(-1)and shorten the culture cycle to 5 d.In terms of coagulation activity,the addition of frustules reduced the in vitro coagulation time by half and the activation time of coagulation by 70%.The hemolysis rate and cytotoxicity of frustules harvested in the two culture modes did not change significantly.The results showed that suspension culture mode and high nutrient concentration culture mode only changed the growth state of Coscinodiscus sp.,while the hemostatic performance remained stable. 展开更多
关键词 diatom culture Coscinodiscus sp frustule hemostatic material hemorrhage control
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Evaluation of ruminal methane and ammonia formation and microbiota composition as affected by supplements based on mixtures of tannins and essential oils using Rusitec
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作者 Giulia Foggi Melissa Terranova +9 位作者 Matteo Daghio Sergej L.Amelchanka Giuseppe Conte Simon Ineichen Monica Agnolucci Carlo Viti Alberto Mantino Arianna Buccioni Michael Kreuzer Marcello Mele 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第4期1607-1622,共16页
Background Dietary supplements based on tannin extracts or essential oil compounds(EOC)have been repeatedly reported as a promising feeding strategy to reduce the environmental impact of ruminant husbandry.A previous ... Background Dietary supplements based on tannin extracts or essential oil compounds(EOC)have been repeatedly reported as a promising feeding strategy to reduce the environmental impact of ruminant husbandry.A previous batch culture screening of various supplements identified selected mixtures with an enhanced potential to mitigate ruminal methane and ammonia formation.Among these,Q-2(named after quebracho extract and EOC blend 2,composed of carvacrol,thymol,and eugenol)and C-10(chestnut extract and EOC blend 10,consisting of oregano and thyme essential oils and limonene)have been investigated in detail in the present study with the semi-continuous rumen simulation technique(Rusitec)in three independent runs.For this purpose,Q-2 and C-10,dosed according to the previous study,were compared with a non-supplemented diet(negative control,NC)and with one supplemented with the commercial EOC-based Agolin^(R) Ruminant(positive control,PC).Results From d 5 to 10 of fermentation incubation liquid was collected and analysed for pH,ammonia,protozoa count,and gas composition.Feed residues were collected for the determination of ruminal degradability.On d 10,samples of incubation liquid were also characterised for bacterial,archaeal and fungal communities by high-throughput sequencing of 16S rRNA and 26S ribosomal large subunit gene amplicons.Regardless of the duration of the fermentation period,Q-2 and C-10 were similarly efficient as PC in mitigating either ammonia(-37%by Q-2,-34%by PC)or methane formation(-12%by C-10,-12%by PC).The PC was also responsible for lower feed degradability and bacterial and fungal richness,whereas Q-2 and C-10 effects,particularly on microbiome diversities,were limited compared to NC.Conclusions All additives showed the potential to mitigate methane or ammonia formation,or both,in vitro over a period of 10 d.However,several differences occurred between PC and Q-2/C-10,indicating different mechanisms of action.The pronounced defaunation caused by PC and its suggested consequences apparently determined at least part of the mitigant effects.Although the depressive effect on NDF degradability caused by Q-2 and C-10 might partially explain their mitigation properties,their mechanisms of action remain mostly to be elucidated. 展开更多
关键词 Additive Bacteria Continuous culture DEGRADABILITY Fermentation Fungi Greenhouse gas In vitro Microbiome RUMEN
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Current status and challenges for cell-cultured milk technology: a systematic review
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作者 Hyuk Cheol Kwon Hyun Su Jung +1 位作者 Vahinika Kothuri Sung Gu Han 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第5期1778-1792,共15页
Cellular agriculture is an innovative technology for manufacturing sustainable agricultural products as an alternative to traditional agriculture.While most cellular agriculture is predominantly centered on the produc... Cellular agriculture is an innovative technology for manufacturing sustainable agricultural products as an alternative to traditional agriculture.While most cellular agriculture is predominantly centered on the production of cultured meat,there is a growing demand for an understanding of the production techniques involved in dairy products within cellular agriculture.This review focuses on the current status of cellular agriculture in the dairy sector and technical challenges for cell-cultured milk production.Cellular agriculture technology in the dairy sector has been classified into fermentation-based and animal cell culture-based cellular agriculture.Currently,various companies synthesize milk components through precision fermentation technology.Nevertheless,several startup companies are pursuing animal cell-based technology,driven by public concerns regarding genetically modified organisms in precision fermentation technology.Hence,this review offers an up-to-date exploration of animal cell-based cellular agriculture to produce milk components,specifically emphasizing the structural,functional,and productive aspects of mammary epithelial cells,providing new information for industry and academia. 展开更多
关键词 Cell culture system Cell-cultured milk Mammary epithelial cells Precision fermentation
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Aboveground carbon sequestration of Cunninghamia lanceolata forests:Magnitude and drivers
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作者 Chen Wang Shuguang Liu +3 位作者 Yu Zhu Andrew R.Smith Ying Ning Deming Deng 《Forest Ecosystems》 SCIE CSCD 2024年第1期32-41,共10页
Understanding the spatial variation,temporal changes,and their underlying driving forces of carbon sequestration in various forests is of great importance for understanding the carbon cycle and carbon management optio... Understanding the spatial variation,temporal changes,and their underlying driving forces of carbon sequestration in various forests is of great importance for understanding the carbon cycle and carbon management options.How carbon density and sequestration in various Cunninghamia lanceolata forests,extensively cultivated for timber production in subtropical China,vary with biodiversity,forest structure,environment,and cultural factors remain poorly explored,presenting a critical knowledge gap for realizing carbon sequestration supply potential through management.Based on a large-scale database of 449 permanent forest inventory plots,we quantified the spatial-temporal heterogeneity of aboveground carbon densities and carbon accumulation rates in Cunninghamia lanceolate forests in Hunan Province,China,and attributed the contributions of stand structure,environmental,and management factors to the heterogeneity using quantile age-sequence analysis,partial least squares path modeling(PLS-PM),and hot-spot analysis.The results showed lower values of carbon density and sequestration on average,in comparison with other forests in the same climate zone(i.e.,subtropics),with pronounced spatial and temporal variability.Specifically,quantile regression analysis using carbon accumulation rates along an age sequence showed large differences in carbon sequestration rates among underperformed and outperformed forests(0.50 and 1.80 Mg·ha^(-1)·yr^(-1)).PLS-PM demonstrated that maximum DBH and stand density were the main crucial drivers of aboveground carbon density from young to mature forests.Furthermore,species diversity and geotopographic factors were the significant factors causing the large discrepancy in aboveground carbon density change between low-and high-carbon-bearing forests.Hotspot analysis revealed the importance of culture attributes in shaping the geospatial patterns of carbon sequestration.Our work highlighted that retaining largesized DBH trees and increasing shade-tolerant tree species were important to enhance carbon sequestration in C.lanceolate forests. 展开更多
关键词 Carbon density Carbon accumulation rate Forest age Spatial variation Cultural influence
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Direct somatic embryogenesis and related gene expression networks in leaf explants of Hippeastrum ‘Bangkok Rose’
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作者 Jingjue Zeng Yi Deng +8 位作者 Shahid Iqbal Jiarui Zhang Kunlin Wu Guohua Ma Lin Li Guangyi Dai Rufang Deng Lin Fang Songjun Zeng 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第2期556-572,共17页
Hippeastrum, a highly diverse genus in the Amaryllidaceae family, is a valuable ornamental bulbous flowering plant. Somatic embryogenesis(SE) is an efficient method for mass production of Hippeastrum plantlets. Previo... Hippeastrum, a highly diverse genus in the Amaryllidaceae family, is a valuable ornamental bulbous flowering plant. Somatic embryogenesis(SE) is an efficient method for mass production of Hippeastrum plantlets. Previous studies have been devoted to the in vitro propagation of Hippeastrum, but the SE and its regulatory networks are rarely reported. In this study, we established a direct SE method of Hippeastrum Bangkok Rose' using leaf bases as explants. MS supplemented with 1.00 mg·L^(-1)NAA +1.00 mg·L^(-1)KT + 0.25 mg·L^(-1)TDZ was the optimal medium for SE. Histological observations showed that the bipolar somatic embryo originated from the epidermal cell layer and underwent initiation,globular, scutellar and coleoptile stages. During SE, endogenous hormones of IAA, CTK, ABA, and SA were highly accumulated. Transcriptomic analysis revealed the genes encoding auxin biosynthesis/metabolic enzymes and efflux carriers were induced, while the auxin receptor of TIR1 and ARF transcriptional repressor of Aux/IAA were down-regulated and up-regulated, respectively, leading to suppression of auxin signaling. In contrast, cytokine signaling was promoted at the early stage of SE, as biosynthesis, transport, and signaling components were up-regulated.Various stress-related genes were up-regulated at the early or late stages of SE. Chromatin remodeling could also be dynamically regulated via distinct expression enzymes that control histone methylation and acetylation during SE. Moreover, key SE regulators, including WOXs and SERKs were highly expressed along with SE. Overall, the present study provides insights into the SE regulatory mechanisms of the Hippeastrum. 展开更多
关键词 Hippeastrum Tissue culture Somatic embryogenesis Gene regulation
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Changes of China’s Status in the Global System and Its Influencing Factors:A Multiple Contact Networks Perspective
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作者 LIU Jian LIU Jibin +2 位作者 YANG Qingshan CAI Sikai LIU Jie 《Chinese Geographical Science》 SCIE CSCD 2024年第2期265-279,共15页
Clarifying China’s position in the global system is an important logical basis for developing national diplomacy.Although much research has been done on China’s development status,most studies have been based on cou... Clarifying China’s position in the global system is an important logical basis for developing national diplomacy.Although much research has been done on China’s development status,most studies have been based on country comparisons or institutional en-vironment.In today’s networked era in which the global economy,trade,personnel,and information are closely connected,studies on China’s global position and its status changes and influencing factors in multiple contact networks are still insufficient.In this study,from the perspective of diverse global contact networks,we constructed economic,cultural,and political influence indices to explore the changes and influencing factors on China’s status in the global system from 2005 to 2018.The results show that during the study period,China’s global influence in the fields of economic ties,cultural exchanges,and political contacts increased significantly,but its influ-ence in the fields of cultural exchanges and political contacts lagged far economic ties.The pattern of China’s economic influence on various economies around the world has shown a transformation from an‘upright pyramid’to an‘inverted pyramid’structure.The proportion of these economies in low-influence zones has decreased from more than 60%in 2005 to less than 20%in 2018.China’s cultural and political influence on various economies around the world has increased significantly;however,for the former,the percentage of high-influence areas is still less than 20%,whereas for the latter the percentage of these economies in medium-and high-influence areas is still less than 50%.Analyses such as a scatter plot matrix show that geographical proximity,economic globalization,close cooperation with developing countries,and a proactive and peaceful foreign policy are important factors in improving China’s status in the diverse global network system. 展开更多
关键词 global system economic ties cultural exchanges political contacts multiple contact networks China’s status
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