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Interaction between Biochar and Algae on Problem Soil
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作者 Tazeen Fatima Khan Abdullah Al Mamun Nipu 《Journal of Materials Science and Chemical Engineering》 2024年第1期56-68,共13页
An in-vitro experiment was conducted to assess the interaction between biochar and algae on a problem soil. Experiments were performed with and without algae to observe the effectiveness of algae for overcoming the ch... An in-vitro experiment was conducted to assess the interaction between biochar and algae on a problem soil. Experiments were performed with and without algae to observe the effectiveness of algae for overcoming the challenges posed by problem soils. At the end of incubation periods, the adsorption and desorption of phosphorus (P) on a problem soil vis-á-vis algal inoculation were determined. Our results showed that different types of biochars adsorbed different amounts of P suggesting that the source of biochar played a crucial role in determining its behavior towards P. Tannery waste biochar significantly adsorbed 147% and 35% more P compared to that of the chicken litter and orange peel biochars respectively. Significant reductions in adsorption were observed when the biochar was used in combination with the algae which could be due to the beneficial effects of algae leading to the amelioration of the problem soil. Adsorption was reduced to 34%, 24% and 20% for the orange peel biochar + algae, chicken litter biochar + algae and tannery waste biochar + algae, respectively compared to the corresponding biochars present as a single solid. Phosphorus (P) desorption was also reduced significantly in presence of algal inoculation. Overall our findings suggest that the application of algae along with biochar in the problem soil could reduce the adsorption of P which would influence the availability of P. 展开更多
关键词 BIOCHAR algaE Problem Soil INTERACTION PHOSPHORUS
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Dynamic Analysis of an Algae-Bacteria Ecological Model
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作者 Gaopeng Sun Hengguo Yu 《Journal of Applied Mathematics and Physics》 2024年第1期362-382,共21页
In the paper, under the framework of exploring the interaction between algae and bacteria, an algae-bacteria ecological model was established to analyze the interaction mechanism and growth coexistence mode between al... In the paper, under the framework of exploring the interaction between algae and bacteria, an algae-bacteria ecological model was established to analyze the interaction mechanism and growth coexistence mode between algicidal bacteria and algae. Firstly, mathematical work mainly provided some threshold conditions to ensure the occurrence of transcritical bifurcation and saddle-node bifurcation, which could provide certain theoretical support for selecting key ecological environmental factors and numerical simulations. Secondly, the numerical simulation work dynamically displayed the evolution process of the bifurcation dynamic behavior of the model (2.1) and the growth coexistence mode of algae and algicidal bacteria. Finally, it was worth summarizing that intrinsic growth rate and combined capture effort of algae population had a strong influence on the dynamic behavior of the model (2.1). Furthermore, it must also be noted that transcritical bifurcation and saddle-node bifurcation were the inherent driving forces behind the formation of steady-state growth coexistence mode between algicidal bacteria and algae. In summary, it was hoped that the results of this study would contribute to accelerating the study of the interaction mechanism between algicidal bacteria and algae. 展开更多
关键词 algaE Algicidal Bacteria Transcritical Bifurcation Saddle-Node Bifurcation Coexistence Mode
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Hydrocarbon generation differences of shales composed of green algal and cyanobacteria: A case study of Mesozoic and Cenozoic saline lacustrine shales in Junggar Basin, NW China
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作者 Miao Yu Gang Gao +7 位作者 Wan-Yun Ma Miao Liu Ni Zhou You-Jin Zhang Dan He Ke-Ting Fan Liu-Lin-Bo Guo Jie Li 《Petroleum Science》 SCIE EI CAS CSCD 2023年第6期3348-3362,共15页
The Mesozoic and Cenozoic strata in the Junggar basin developed two sets of shallow to semi-deep lacustrine shale, namely, the Cretaceous Qingshuihe Formation (K_(1q)) and the Paleogene Anjihaihe Formation (E_(2-3a)).... The Mesozoic and Cenozoic strata in the Junggar basin developed two sets of shallow to semi-deep lacustrine shale, namely, the Cretaceous Qingshuihe Formation (K_(1q)) and the Paleogene Anjihaihe Formation (E_(2-3a)). Through organic petrology and scanning electron microscope (SEM) observation, it is found that the primary hydrocarbon-generating organic matter (OM) in the two sets of strata is different. The biological precursor of the E_(2-3a) OM is mainly green algae (Pediastrum), while the precursor of K_(1q) kerogen is mainly cyanobacteria (Oscillatoria). Then, the E_(2-3a) green algae-rich shale and K_(1q) cyanobacteria-rich shale were subjected to hydrous pyrolysis and kinetic analysis, respectively. The results show that the evolution modes of hydrocarbon generation of the typical shales are very different. Green algae have the characteristics of a low oil generation threshold, heavy oil quality, and no prominent oil peak, while cyanobacteria have the characteristics of late oil generation, concentrated hydrocarbon generation, and relatively light oil quality. The characteristics of oil generation can also be well reflected in the composition evolution of the crude oil components. The carbon isotope of gas, kerogen, and extracts of the E_(2-3a) green algae-rich shale are significantly heavier than the K_(1q) cyanobacteria-rich shale, which may be related to the living habits of their biological precursors, carbon source usage, photosynthesis efficiency, and carbon fixation efficiency. 展开更多
关键词 Green algae CYANOBACTERIA Shale Anjhaihe Formation Qingshuihe Formation Junggar Basin
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Phyllosphere eukaryotic microalgal communities in rainforests:Drivers and diversity
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作者 Ben-Wen Liu Shu-Yin Li +1 位作者 Huan Zhu Guo-Xiang Liu 《Plant Diversity》 SCIE CAS CSCD 2023年第1期45-53,共9页
Phyllosphere algae are common in tropical rainforests,forming visible biofilms or spots on plant leaf surfaces.However,knowledge of phyllosphere algal diversity and the environmental factors that drive that diversity ... Phyllosphere algae are common in tropical rainforests,forming visible biofilms or spots on plant leaf surfaces.However,knowledge of phyllosphere algal diversity and the environmental factors that drive that diversity is limited.The aim of this study is to identify the environmental factors that drive phyllosphere algal community composition and diversity in rainforests.For this purpose,we used single molecule real-time sequencing of full-length 18S rDNA to characterize the composition of phyllosphere microalgal communities growing on four host tree species(Ficus tikoua,Caryota mitis,Arenga pinnata,and Musa acuminata) common to three types of forest over four months at the Xishuangbanna Tropical Botanical Garden,Yunnan Province,China.Environmental 18S rDNA sequences revealed that the green algae orders Watanabeales and Trentepohliales were dominant in almost all algal communities and that phyllosphere algal species richness and biomass were lower in planted forest than in primeval and reserve rainforest.In addition,algal community composition differed significantly between planted forest and primeval rainforest.We also found that algal communities were affected by soluble reactive phosphorous,total nitrogen,and ammonium contents.Our findings indicate that algal community structure is significantly related to forest type and host tree species.Furthermore,this study is the first to identify environmental factors that affect phyllosphere algal communities,significantly contributing to future taxonomic research,especially for the green algae orders Watanabeales and Trentepohliales.This research also serves as an important reference for molecular diversity analysis of algae in other specific habitats,such as epiphytic algae and soil algae. 展开更多
关键词 Full-length 18S rDNA sequences Cryptic diversity Environmental factors High-throughput sequence Phyllosphere algae Tropical rainforest
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Preparation methods,biological activities,and potential applications of marine algae oligosaccharides:a review
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作者 Lixin Zheng Yang Liu +2 位作者 Shijie Tang Wancong Zhang Kit-Leong Cheong 《Food Science and Human Wellness》 SCIE CSCD 2023年第2期359-370,共12页
Marine algae are valuable sources of health-promoting molecules that have been consumed by Asians for decades.Among aquatic flora,marine algae stand out in terms of high content of marine algae polysaccharides(MAP)suc... Marine algae are valuable sources of health-promoting molecules that have been consumed by Asians for decades.Among aquatic flora,marine algae stand out in terms of high content of marine algae polysaccharides(MAP)such as carrageenan,alginate,fucoidan,laminaran,agarose,rhamnan,and ulvan.When hydrolyzed,MAP generate marine algae oligosaccharides(MAO),which have attracted interest in recent years due to their superior solubility compared with MAP.Besides,MAO have been demonstrated numerous biological activities including antioxidant,antidiabetic,anti-inflammatory,antimicrobial,and prebiotic activities.Thus,this review summarizes the main chemical classes of MAO,their sources,and the main processes used for their production(i.e.,physical,chemical,and biological methods),coupled with a discussion of the advantages and disadvantages of these methods.Highlights of the biological activities of MAO and their potential applications in food,nutraceutical,and pharmaceuticals would also be discussed and summarized. 展开更多
关键词 Marine algae MAO Preparation methods Biological activities Potential applications
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Two-stage reproduction derived from cells of thallus could directly contribute to seeds for green tidal algal Enteromorpha(Ulva) prolifera/clathrata bloom,with disclosure of their ephemeral trait
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作者 Bingxin Huang Lanping Ding +4 位作者 Yao Zhang Youxuan Guo Junxia Liang Yanqi Xie Yue Chu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第9期101-112,共12页
Green tidal algal Enteromorpha species complete their life cycles by the isomorphic alternation of generations.The provenance of green tide caused by them in the western Yellow Sea has been disputed. The cell reproduc... Green tidal algal Enteromorpha species complete their life cycles by the isomorphic alternation of generations.The provenance of green tide caused by them in the western Yellow Sea has been disputed. The cell reproduction derived from adult thallus was observed on E. clathrata collected from Shantou City, Guangdong Province in this study. Subsequently, it further found that E. proliferia collected from Qingdao City, Shandong Province and Qinhuangdao City, Hebei Province, produced reproductive cells by somatic cells of its early infantile thallus or branch. The latter is functionally similar to that the seedlings of red alga Porphyra yezoensis produce the monospores, and could exquisitely explain the ephemeral or opportunistic trait and environmental adaptation ability of Enteromorpha species. Changes in growth conditions may induce the two types of cell reproduction.They contribute to the bloom, and can effectively reveal the seasonally occurring large-scale and on-year and offyear phenomenon. The latter may have played a decisive role in its formation. This paper analyses the legal status of the species name, the type of generation during bloom, ephemeral traits, the role of microscopic propagule, the area of origin, on-year and off-year phenomenon, early warning and prevention and control of the species, and so on. On this basis, further study on the influence of environmental factors on cell reproduction of early infantile thalli or branches will achieve a positive effect for early warning and prevention and control of the green tidal algal bloom. 展开更多
关键词 green tidal algae Yellow Sea opportunistic trait on-year and off-year early infantile alternation of generations prediction on the occurrence process
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Effect of Algae on Melon(Cucumis melo subsp.agrestis var.conomon)Growth and Development under Drought-Stress Conditions
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作者 M.Zeki KARİPÇİN BehcetİNAL 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第11期3177-3193,共17页
Due to climate change,it is necessary to develop plant varieties that are resilient to climate conditions and resistant to abiotic and biotic stresses.The use of microalgae,which are microorganisms that contain carboh... Due to climate change,it is necessary to develop plant varieties that are resilient to climate conditions and resistant to abiotic and biotic stresses.The use of microalgae,which are microorganisms that contain carbohydrates,proteins,lipids,and vitamins,against drought tolerance is a new approach.The aim of the current study was to determine the drought-related mechanisms in the conomon melon genotype and develop drought-tolerant melon cultivars.Morphological,physiological,pomological,and molecular analyses were carried out on the algae-treated genotypes.It has been determined that commercial algae application provides the best results in leaf temperature,leaf relative water contents(LRWC),plant height,fruit length,fruit diameter,and yield,while Cag Cag(a special river in the region)stream algae application gives better results in main stem diameter.It was determined that the number of nodes in the control(without algae)plots was higher than in the other two treatments.Yield and LRWC and plant height values of genotype 7 were the best values among other genotypes.The leaf temperature measurement was lower on genotype 9 than on the other genotypes.While the highest fruit length value was measured in genotype 1,genotype 8 was superior in the main stem diameter,fruit diameter,and the number of nodes among the remaining plant materials.In terms of yield,it was determined that the interaction between genotype 2 and the commercial algae resulted in the best outcomes.In addition,the results of the genetic evaluation revealed that the materials used were not genetically distant from each other and more detailed genetic evaluations are needed.The molecular kinship analysis revealed that the genotypes used in the study were divided into three distinct groups,with individuals within each group exhibiting a high degree of relatedness to one another.As a result of the study,it was found that the application of microalgae had significant effects on improving the drought tolerance of Cucumis melo subsp.agrestis var.conomon genotypes. 展开更多
关键词 DROUGHT algaE molecular taxonomy Cucumis melo subsp.agrestis var.conomon
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Influence of External Factors on Algae Biomass in Lake Khadicha (Bukhara, Uzbekistan)
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作者 Barno Bakhriddinovna Kobulova Yigitali Shavkatillayevich Tashpulatov 《American Journal of Plant Sciences》 2023年第12期1399-1409,共11页
Aquatic plant communities, which largely determine the ecological state of aquatic ecosystems and the quality of their waters, are the most important components in the biological monitoring system. Lake Khadicha is a ... Aquatic plant communities, which largely determine the ecological state of aquatic ecosystems and the quality of their waters, are the most important components in the biological monitoring system. Lake Khadicha is a unique natural body of water that is used for growing commercial fish. In recent years, due to heavy loads of abiotic and anthropogenic factors, the lake water has become highly saline. This phenomenon greatly affects the biodiversity of aquatic organisms, in addition to algae. During 2019-2021, the algae flora of Lake Khadicha was studied. 216 species of algae were identified as part of the algal flora. Their relationship with external factors such as water temperature, salinity and pH was studied. The seasonal abundance and biomass of algal flora areas of the lake were determined. Quantitative indicators of the dominant species in each season and their bioecological characteristics are identified. 展开更多
关键词 ABUNDANCE algaE BIOMASS Environmental Factors Lake Khadicha
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Dynamic Analysis of an Algae-Fish Harvested Model with Allee Effect
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作者 Xiaoyu Song Hengguo Yu Min Zhao 《Journal of Applied Mathematics and Physics》 2023年第10期2938-2962,共25页
In this paper, an algae-fish harvested model with Allee effect was established to further explore the dynamic evolution mechanism under the influence of key factors. Mathematical theoretical work not only investigated... In this paper, an algae-fish harvested model with Allee effect was established to further explore the dynamic evolution mechanism under the influence of key factors. Mathematical theoretical work not only investigated the existence and stability of all possible equilibrium points, but also probed into the occurrence of transcritical and Hopf bifurcation. The numerical simulation works verified the effectiveness of the theoretical derivation results and displayed rich bifurcation dynamical behaviors, which showed that Allee effect and harvest have played a vital role in the dynamic relationship between algae and fish. In summary, it was expected that these research results would be beneficial for promoting the study of bifurcation dynamics in aquatic ecosystems. 展开更多
关键词 algae and Fish Model Allee Effect HARVESTING Equilibrium Point BIFURCATION
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Exploring the Therapeutic Potential of Algae-Based Sheet Masks in Skincare: A Comprehensive Study of Cosmetological Benefits and Microbiome Balanced Interactions
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作者 Ciska Janssens-Böcker Karin Wiesweg Claudia Doberenz 《Journal of Cosmetics, Dermatological Sciences and Applications》 2023年第4期277-301,共25页
Research in dermatology is exploring bio-compatible materials like alginate and calcium sulphate for use in skincare products, such as facial sheet masks. Alginate (from seaweed) has wound healing and hydration proper... Research in dermatology is exploring bio-compatible materials like alginate and calcium sulphate for use in skincare products, such as facial sheet masks. Alginate (from seaweed) has wound healing and hydration properties, while calcium assists in maintaining skin balance and protection. In this study we explore the effects of an algae-calcium based sheet mask on skin. Materials and Methods: In-vitro studies investigated the purpose, process and effectiveness of an algae-calcium dry sheet mask (Algae Mask-MedSkin Solutions Dr. Suwelack). The mask is made from brown algae and undergoes a lyophilization and stabilization process to form its final structure. The mask’s properties were tested using scanning electron microscopy (SEM) and its performance was assessed on human skin biopsies. Various tests were performed, such as measuring the release of ionic constituents and concentration of calcium ions, and the fibroblast cell-activating effect. Clinical evaluations and skin microbiome assessment were conducted on healthy volunteers to assess the mask’s effect on the skin. Results and Conclusion: The study validates the benefits of macro algae-based sheet masks for skincare, with significant cosmetic effects and high tolerance due to its composition. Notably, the algae based mask releases substantial calcium ions, hydrates, minimizes skin roughness and wrinkles, regulates pH levels, and maintains skin microbiome diversity. It also decreases Corynebacterium species found on the skin, suggesting potential to modify skin microbiome. . 展开更多
关键词 algaE Sheet Mask Calcium Skin Aging HYDRATION MICROBIOME Skin pH
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Transcriptome sequencing of essential marine brown and red algal species in China and its significance in algal biology and phylogeny
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作者 WU Shuangxiu SUN Jing +7 位作者 CHI Shan WANG Liang WANG Xumin LIU Cui LI Xingang YIN Jinlong LIU Tao YU Jun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第2期1-12,共12页
Most phaeophytes (brown algae) and rhodophytes (red algae) dwell exclusively in marine habitats and play important roles in marine ecology and biodiversity. Many of these brown and red algae are also important res... Most phaeophytes (brown algae) and rhodophytes (red algae) dwell exclusively in marine habitats and play important roles in marine ecology and biodiversity. Many of these brown and red algae are also important resources for industries such as food, medicine and materials due to their unique metabolisms and me-tabolites. However, many fundamental questions surrounding their origins, early diversification, taxonomy, and special metabolisms remain unsolved because of poor molecular bases in brown and red algal study. As part of the 1 000 Plant Project, the marine macroalgal transcriptomes of 19 Phaeophyceae species and 21 Rhodophyta species from China's coast were sequenced, covering a total of 2 phyla, 3 classes, 11 orders, and 19 families. An average of 2 Gb per sample and a total 87.3 Gb of RNA-seq raw data were generated. Approxi-mately 15 000 to 25 000 unigenes for each brown algal sample and 5 000 to 10 000 unigenes for each red algal sample were annotated and analyzed. The annotation results showed obvious differences in gene expres-sion and genome characteristics between red algae and brown algae;these differences could even be seen between multicellular and unicellular red algae. The results elucidate some fundamental questions about the phylogenetic taxonomy within phaeophytes and rhodophytes, and also reveal many novel metabolic pathways. These pathways include algal CO2 fixation and particular carbohydrate metabolisms, and related gene/gene family characteristics and evolution in brown and red algae. These findings build on known algal genetic information and significantly improve our understanding of algal biology, biodiversity, evolution, and potential utilization of these marine algae. 展开更多
关键词 PHAEOPHYCEAE brown algae RHODOPHYTA red algae marine macroalgae transcriptome sequencing secondary generation sequencing
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Effect of Silver Nanoparticles on Growth of Eukaryotic Green Algae 被引量:5
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作者 Anjali Dash Anand P.Singh +2 位作者 Bansh R.Chaudhary Sunil K.Singh Debabrata Dash 《Nano-Micro Letters》 SCIE EI CAS 2012年第3期158-165,共8页
Silver nanoparticles,endowed with powerful antimicrobial property,are the most widely used nanomaterial in consumer products,with associated risk of their easy access to environment and freshwater ecosystems by surfac... Silver nanoparticles,endowed with powerful antimicrobial property,are the most widely used nanomaterial in consumer products,with associated risk of their easy access to environment and freshwater ecosystems by surface runoff.Although toxic effects of nanosilver on bacterial,fungal and mammalian cells have been documented,its impact on algal growth remains unknown.Pithophora oedogonia and Chara vulgaris are predominant members of photosynthetic eukaryotic algae,which form major component of global aquatic ecosystem.Here we report for the first time that nanosilver has significant adverse effects on growth and morphology of these filamentous green algae in a dose-dependent manner.Exposure of algal thalli to increasing concentrations of silver nanoparticles resulted in progressive depletion in algal chlorophyll content,chromosome instability and mitotic disturbance,associated with morphological malformations in algal filaments.SEM micrographs revealed dramatic alterations in cell wall in nanoparticle-treated algae,characterized with cell wall rupture and degradation in Pithophora.Although these observations underscore severe deleterious effects of nanosilver on aquatic environment,the information can also be exploited as a bioengineering strategy to control unwanted and persistent growth of noxious algal weeds that clog the municipal water supply and water channels and produce fouling of water bodies. 展开更多
关键词 Silver nanoparticles Green algae algal growth Photosynthetic pigment NANOTOXICITY
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Alga-lysing bioreactor and dominant bacteria strain 被引量:3
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作者 PEI Hai-yan HU Wen-rong +1 位作者 MU Rui-min LI Xiao-cai 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第5期546-552,共7页
Alga-lysing bacteria have been paid much attention to in recent years. In this study, the alga-lysing strain P05 which was isolated from an immobilizing biosystem was immobilized by coke and elastic filler, forming tw... Alga-lysing bacteria have been paid much attention to in recent years. In this study, the alga-lysing strain P05 which was isolated from an immobilizing biosystem was immobilized by coke and elastic filler, forming two biological reactors. The removal efficiencies of algae, NH4^+-N and organic matter using the two reactors were studied. The results showed that strain P05 was an ideal algal-lysing bacteria strain because it was easy to be immobilized by coke and elastic filler which are of cheap, low biodegradability and the simple immobilization procedure. After 7 d filming, the biological film could be formed and the reactors were used to treat the eutrophic water. These two reactors were of stability and high effect with low cost and easy operation. The optimal hydraulic retention time (HRT) of each reactor was 4 h. The algae removal rates were 80.38% and 82.1% (in term of Chl-α) of coke reactor and filler reactor, respectively. And that of NH4^+-N were 52.3% and 52.7%. The removal rates of CODMn were 39.03% and 39.64%. The strain P05 was identified as Bacillus sp. by PCR amplification of the 16S rRNA gene, BLAST analysis, and comparison with sequences in the GenBank nucleotide database. 展开更多
关键词 alga-lysing algae removal IMMOBILIZATION 16S rRNA Bacillus sp.
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Effect of Tropical Algae as Additives on Rumen <i>in Vitro</i>Gas Production and Fermentation Characteristics 被引量:5
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作者 Baptiste Dubois Nigel W. Tomkins +4 位作者 Robert D. Kinley Mei Bai Scott Seymour Nicholas A. Paul Rocky de Nys 《American Journal of Plant Sciences》 2013年第12期34-43,共10页
Algae have become an area of intensive research in many fields of study. Areas of application are becoming increasingly diverse with the advent of technologies particularly in the mass production of algae biomass. Alg... Algae have become an area of intensive research in many fields of study. Areas of application are becoming increasingly diverse with the advent of technologies particularly in the mass production of algae biomass. Algae contain complex bioactive compounds and these are gaining importance in emerging technologies with nutritional and environmental applications. In this study, a preliminary investigation evaluated 15 species of algae from the major categories of marine and fresh water algae for their potential as inclusions in ruminant diets for management of greenhouse gas emissions. It was hypothesized that algae would positively affect rumen fermentation and gas production while reducing methane production. The hypothesis was tested using an Ankom automated gas monitoring system and rumen fluid from Bos indicus steers fed tropical forage diets. The results were variable between algae species with some showing a significant reduction in total gas and methane production, with others increasing gas and fermentation. The red and brown algae stand out as having potential for greenhouse gas mitigation with the brown alga Cystoseira having the most prominent effect. The effects observed on fermentation may be manipulated through dosage management and beneficial effects could be potentially maximized by preparing combinations of algal supplements. It has been demonstrated in this study that algae have the potential to assist in rumen fermentation management for improved gas production, and greenhouse gas abatement. 展开更多
关键词 algaE Enteric Gas MACROalgaE Methane RUMEN SEAWEED
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(AlGa)As可见光激光器的镜面保护 被引量:1
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作者 廖柯 《半导体光电》 CAS CSCD 北大核心 1990年第2期138-141,共4页
本文介绍了一种可见光激光器端面镜面保护方法。用电子束蒸发在可见光激光器的两个镜面上分别镀上0.75 λ/2和λ/2厚的 Al_2O_3钝化膜,并就镀膜对激光器性能的影响进行了测试研究。经过镜面保护的可见光激光器寿命有很大改善,且由于一... 本文介绍了一种可见光激光器端面镜面保护方法。用电子束蒸发在可见光激光器的两个镜面上分别镀上0.75 λ/2和λ/2厚的 Al_2O_3钝化膜,并就镀膜对激光器性能的影响进行了测试研究。经过镜面保护的可见光激光器寿命有很大改善,且由于一个端面镀上0.75 λ/2抗反射膜,使激光器的极限输出功率有一定的提高。 展开更多
关键词 (alga)As 可见 激光器 镜面 保护
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ALGA在岸基导弹航路规划中的应用研究
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作者 王光源 汲万峰 +2 位作者 张非非 章尧卿 孙钧正 《电光与控制》 北大核心 2012年第5期1-6,共6页
针对基本遗传算法(GA)易局部收敛的缺陷,设计了基于模式搜索的自学习算子,提出一种基于模式搜索的自学习遗传算法(ALGA)。通过仿真测试函数将ALGA与基本遗传算法、自适应遗传算法(AGA)进行比较,显示改进的ALGA提高了算法的综合搜索能力... 针对基本遗传算法(GA)易局部收敛的缺陷,设计了基于模式搜索的自学习算子,提出一种基于模式搜索的自学习遗传算法(ALGA)。通过仿真测试函数将ALGA与基本遗传算法、自适应遗传算法(AGA)进行比较,显示改进的ALGA提高了算法的综合搜索能力。将改进的ALGA运用到岸基导弹航路规划中,并进行仿真实验,仿真结果验证了改进算法的有效性。 展开更多
关键词 航路规划 模式搜索 alga 遗传算法
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Effects of the sunscreen ultraviolet filter,oxybenzone,on green microalgae
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作者 Ming-Li TEOH Nur Suhaida SANUSI +1 位作者 Ching-Yee WONG John BEARDALL 《Advances in Polar Science》 CSCD 2020年第2期112-123,共12页
Ultraviolet(UV)filters are widely used in sunscreen and personal care products due to their ability to give protection to our skin from UV radiation.Oxybenzone,commonly known as benzophenone-3,is one type of UV filter... Ultraviolet(UV)filters are widely used in sunscreen and personal care products due to their ability to give protection to our skin from UV radiation.Oxybenzone,commonly known as benzophenone-3,is one type of UV filter found as the active ingredient in many pharmaceutical products.Although oxybenzone has been extensively studied as an environmental toxicant in the ecosystem,little is known about its toxicity effects on microalgae.The effects of oxybenzone on growth(measured as OD620 nm,chlɑand carotenoids)and macromolecular composition of polar microalgae(Chlorella UMACC 400 and Chlorella UMACC 401)and temperate microalgae(Chlorella sp.,Chlamydomonas reinhardtii,Scenedesmus quadricauda)were investigated.These microalgae were cultured in triplicate and exposed to different oxybenzone concentrations(0,100,200,300 and 400 mg·L-1),at 4℃and 18 for polar and temperate species respectively,for 96 h.The oxybenzone concentrations used℃represent a range from environmental to extreme concentrations to understand the impact of this toxicant on microalgae.The results showed that the highest concentration of oxybenzone(300 and 400 mg·L-1)had adverse effects on growth rate and biomass of these microalgae.However,exposure to oxybenzone concentrations ranging from 200 mg·L-1 to 400 mg·L-1 did not have significant effects on S.quadricauda growth.The exposure to oxybenzone at higher concentrations also led to changes in cell structure after 96 h.Generally,protein and carbohydrate content of all microalgae except S.quadricauda increased with increasing oxybenzone concentrations.Protein content increased significantly when cells were exposed to oxybenzone,though effects were greater in the polar species,suggesting that it could be one of the adaptive strategies that enabled these microalgae to tolerate oxybenzone.Further investigation is required to determine the effects of oxybenzone on other features of microalgal performance at relevant environmental concentrations. 展开更多
关键词 polar algae temperate algae CHLORELLA benzophenone-3 emerging contaminants
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The“harmful algae and algal toxins in coastal waters of China:investigation and database”project
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作者 Tian YAN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2022年第6期2081-2093,共13页
The“harmful algae and algal toxins in coastal waters of China:investigation and database”project(HAATC)is funded(US$2.3 million)by the Ministry of Science and Technology of China for 60 months starting on the 1st Ja... The“harmful algae and algal toxins in coastal waters of China:investigation and database”project(HAATC)is funded(US$2.3 million)by the Ministry of Science and Technology of China for 60 months starting on the 1st Jan 2019.Since the 1990s,national projects and other related work have greatly improved harmful algal bloom(HAB)research in China.However,the existing research on HABs is often limited to specific sea areas or specific algal bloom disasters,which is insufficient for understanding the long-term evolution of HAB occurrence under the influence of intensified human activity and global change.The HAATC project intends to determine the overall distribution of marine harmful microalgae and macroalgae,and marine algal toxins(in phytoplankton and shellfish)through a large-scale investigation in the coastal waters of China and continuous investigation in key sea areas.It also aims to observe biotic and abiotic processes during harmful red tides and green tides,and establish an open database and query platform of HABs in China.The research consortium,led by chief scientist Prof.Tian YAN,includes approximately 100 scientists and students.More than 2 years of work have shown the increased distribution of HAB species(including cysts)and algal toxins in China’s coastal waters,the increased occurrence of macroalgae blooms(mainly by Ulva prolifera and Sargassum horneri)in the Southern Yellow Sea,increased amount of causative species being identified due to the use of molecular technologies in taxonomy,and new records of algal toxins such as azaspiracid,cycloimines and neurotoxinsβ-N-methylamino-l-alanine have been detected,which complicates the research in algal toxins and toxicology.Eventually,the project will provide systematic basic data and techniques for the rapid and accurate identification of harmful algae species to support the research,monitoring,and control of harmful algal blooms,as well as seafood safety management in China. 展开更多
关键词 harmful algae algal toxins coastal waters of China DATABASE
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Oxidative effects of the harmful algal blooms on primary organisms of the food web
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作者 JOAQUIN CABRERA PAULA MARIELA GONZALEZ SUSANA PUNTARULO 《BIOCELL》 SCIE 2019年第2期41-50,共10页
Degraded water quality from nutrient pollution,physical,biological,and other chemical factors contributes to the development and persistence of many harmful algal blooms(HAB s).The complex dynamics of the HAB s is a c... Degraded water quality from nutrient pollution,physical,biological,and other chemical factors contributes to the development and persistence of many harmful algal blooms(HAB s).The complex dynamics of the HAB s is a challenge to marine ecosystems for the toxic effects reported.The consequences include fish,bird,and mammal mortality,respiratory or digestive tract problems,memory loss,seizures,lesions and skin irritation in many organisms.This review is intended to briefly summarize the recent reported information on harmful marine toxin deleterious effects over the primary organisms of the food web,namely algae,zooplankton and invertebrates.Special focus is made on oxidative stress status of cells and tissues.Even though in situ field research is less controlled than laboratory studies,in which the organisms are directly exposed to the toxins under consideration,both types of approaches are required to fully understand such a complex scenario.On top of that,the contribution of the increasing water temperatures in the sea,as a consequence of the global climate change,will be addressed as a topic for further studies,to evaluate the effect on regulating algal growth,species composition,trophic structure,metabolic stress and function of aquatic ecosystems. 展开更多
关键词 Harmful algal toxins oxidative stress algaE ZOOPLANKTON invertebrates
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Seasonal change of ice algal and phytoplankton assemblages in the Nella Fjord near Zhongshan Station, East Antarctica
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作者 何剑锋 陈波 《Chinese Journal of Polar Science》 2000年第2期113-122,共10页
The ice algal and phytoplankton assemblages were studied from Nella Fjord near Zhongshan Station, East Antarctica from April 12 to December 30, 1992. Algal blooms occurred about 3 cm thick on the bottom of sea ice in ... The ice algal and phytoplankton assemblages were studied from Nella Fjord near Zhongshan Station, East Antarctica from April 12 to December 30, 1992. Algal blooms occurred about 3 cm thick on the bottom of sea ice in late April and mid November to early December respectively, and a phytoplankton bloom appeared in the underlying surface water in mid December following the spring ice algal bloom. The biomass in ice bottom was 1 to 3 orders of magnitude higher than that of surface water. Amphiprora kjellmanii, Berkeleya sp., Navicula glaciei, Nitzschia barkelyi, N. cylindrus /N. curta, N. lecointei and Nitzschia sp. were common in the sea ice temporarily or throughout the study period. The biomass in a certain ice segment was decreased gradually and the dominant species were usually succeeded as the season went on. Nitzschia sublineata and Dactyliosolen antarctica were two seasonal dominant species only observed in underlying water column. The assemblages between bottom of ice and underlying surface water were different except when spring ice algae bloomed. The evidence shows that the ice algal blooms occurred mainly by in situ growth of ice algae, and the phytoplankton bloom was mostly caused by the release of ice algae. 展开更多
关键词 ANTARCTICA sea ice ice algae PHYTOPLANKTON biomass algal composition.
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