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Screening of Polyphosphate Accumulating Organisms and Their Phosphorus Removal Performance
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作者 Miaoxuan HONG Qitong LIANG +1 位作者 Yating HUANG Shasha LIU 《Asian Agricultural Research》 2024年第1期22-24,共3页
[Objectives]To study the phosphorus removal performance of phosphate accumulating organisms(PAOs).[Methods]Activated sludge from domestic sewage treatment plant was used as the strain source,and phosphate accumulating... [Objectives]To study the phosphorus removal performance of phosphate accumulating organisms(PAOs).[Methods]Activated sludge from domestic sewage treatment plant was used as the strain source,and phosphate accumulating organisms were screened by plate streaking method and dilution coating plate method.Six kinds of excellent phosphate accumulating organisms were obtained by metachromatic granule staining experiment,total phosphorus experiment and simulated sewage phosphorus removal experiment to assist the observation of bac-terial morphology and experiment of phosphorus removal capacity.In addition,the influencing factors of phosphorus removal capacity(nitrogen source,trace metal ions)were analyzed.[Results]In the case of simulated sewage,the phosphorus removal rate of strain b was the highest,reaching 66.25%,while the phosphorus removal rate of strain e and f was about 10%lower than that of the phosphorus uptake experiment.[Conclusions]This study is expected to provide a theoretical reference for the gradual optimization of the screening method of phosphorus re-moval bacteria in domestic sewage treatment. 展开更多
关键词 Phosphate accumulating organisms(PAOs) Separation and screening Biological phosphorus removal
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Incidence, risk factors and clinical outcome of multidrug-resistant organisms after heart transplantation
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作者 Sophia Hatzianastasiou Paraskevas Vlachos +12 位作者 Georgios Stravopodis Dimitrios Elaiopoulos Afentra Koukousli Josef Papaparaskevas Themistoklis Chamogeorgakis Kyrillos Papadopoulos Theodora Soulele Despoina Chilidou Kyriaki Kolovou Aggeliki Gkouziouta Michail Bonios Stamatios Adamopoulos Stavros Dimopoulos 《World Journal of Transplantation》 2024年第2期107-118,共12页
BACKGROUND Transplant recipients commonly harbor multidrug-resistant organisms(MDROs),as a result of frequent hospital admissions and increased exposure to antimi-crobials and invasive procedures.AIM To investigate th... BACKGROUND Transplant recipients commonly harbor multidrug-resistant organisms(MDROs),as a result of frequent hospital admissions and increased exposure to antimi-crobials and invasive procedures.AIM To investigate the impact of patient demographic and clinical characteristics on MDRO acquisition,as well as the impact of MDRO acquisition on intensive care unit(ICU)and hospital length of stay,and on ICU mortality and 1-year mortality post heart transplantation.METHODS This retrospective cohort study analyzed 98 consecutive heart transplant patients over a ten-year period(2013-2022)in a single transplantation center.Data was collected regarding MDROs commonly encountered in critical care.RESULTS Among the 98 transplanted patients(70%male),about a third(32%)acquired or already harbored MDROs upon transplantation(MDRO group),while two thirds did not(MDRO-free group).The prevalent MDROs were Acinetobacter baumannii(14%),Pseudomonas aeruginosa(12%)and Klebsiella pneumoniae(11%).Compared to MDRO-free patients,the MDRO group was characterized by higher body mass index(P=0.002),higher rates of renal failure(P=0.017),primary graft dysfunction(10%vs 4.5%,P=0.001),surgical re-exploration(34%vs 14%,P=0.017),mechanical circulatory support(47%vs 26%P=0.037)and renal replacement therapy(28%vs 9%,P=0.014),as well as longer extracorporeal circulation time(median 210 vs 161 min,P=0.003).The median length of stay was longer in the MDRO group,namely ICU stay was 16 vs 9 d in the MDRO-free group(P=0.001),and hospital stay was 38 vs 28 d(P=0.006),while 1-year mortality was higher(28%vs 7.6%,log-rank-χ2:7.34).CONCLUSION Following heart transplantation,a predominance of Gram-negative MDROs was noted.MDRO acquisition was associated with higher complication rates,prolonged ICU and total hospital stay,and higher post-transplantation mortality. 展开更多
关键词 Heart transplantation Multi drug resistant organisms Transplantation complications Transplantation outcome
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Verify the Function of a Potential Growth-Regulating Gene in Marine Bivalve Using a Candidate Model Organism Mulinia lateralis
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作者 WANG Chen KONG Lingling +6 位作者 LIAN Shanshan YANG Zujing MENG Deting LI Moli ZHANG Xiangchao BAO Zhenmin HU Xiaoli 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第4期1012-1022,共11页
A better understanding of genetic bases of growth regulation is essential for bivalve breeding,which is helpful to improve the yield of the commercially important bivalves.While previous studies have identified some c... A better understanding of genetic bases of growth regulation is essential for bivalve breeding,which is helpful to improve the yield of the commercially important bivalves.While previous studies have identified some candidate genes accounting for variation in growth-related traits through genotype-phenotype association analyses,seldom of them have verified the functions of these putative,growth-related genes beyond the genomic level due to the difficulty of culturing commercial bivalves under laboratory conditions.Fortunately,dwarf surf clam Mulinia lateralis can serve as a model organism for studying marine bivalves given its short generation time,the feasibility of being grown under experimental conditions and the availability of genetic and biological information.Using dwarf surf clam as a model bivalve,we characterize E2F3,a gene that has been found to account for variation in growth in scallops by a previous genome-wide association study,and verify its function in growth regulation through RNA interference(RNAi)experiments.For the first time,E2F3 in dwarf surf clam,which is termed as MulE2F3,is characterized.The results reveal that dwarf surf clams with MulE2F3 knocked down exhibit a reduction in both shell size and soft-tissue weight,indicating the functions of MulE2F3 in positively regulating bivalve growth.More importantly,we demonstrate how dwarf surf clam can be used as a model organism to investigate gene functions in commercial bivalves,shedding light on genetic causes for variation in growth to enhance the efficiency of bivalve farming. 展开更多
关键词 growth-regulating gene FUNCTION marine bivalve model organism Mulinia lateralis
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Machines,Tools and Tool Transporter Concurrent Scheduling in Multi⁃machine FMS with Alternative Routing Using Symbiotic Organisms Search Algorithm
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作者 M.Padma Lalitha N.Sivarami Reddy +1 位作者 K.L.Narasimhamu I.Suneetha 《Journal of Harbin Institute of Technology(New Series)》 CAS 2023年第6期35-61,共27页
This study explored the concurrent scheduling of machines, tools, and tool transporter(TT) with alternative machines in a multi-machine flexible manufacturing system(FMS), taking into mind the tool transfer durations ... This study explored the concurrent scheduling of machines, tools, and tool transporter(TT) with alternative machines in a multi-machine flexible manufacturing system(FMS), taking into mind the tool transfer durations for minimization of the makespan(MSN). When tools are expensive, just a single copy of every tool kind is made available for use in the FMS system. Because the tools are housed in a central tool magazine(CTM), which then distributes and delivers them to many machines, because there is no longer a need to duplicate the tools in each machine, the associated costs are avoided. Choosing alternative machines for job operations(jb-ons), assigning tools to jb-ons, sequencing jb-ons on machines, and arranging allied trip activities, together with the TT’s loaded trip times and deadheading periods, are all challenges that must be overcome to achieve the goal of minimizing MSN. In addition to a mixed nonlinear integer programming(MNLIP) formulation for this simultaneous scheduling problem, this paper suggests a symbiotic organisms search algorithm(SOSA) for the problem’s solution. This algorithm relies on organisms’ symbiotic interaction strategies to keep living in an ecosystem. The findings demonstrate that SOSA is superior to the Jaya algorithm in providing solutions and that using alternative machines for operations helps bring down MSN. 展开更多
关键词 machines tool transporter and tools scheduling FMS tool transporter symbiotic organisms search algorithm.
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Multidrug resistant organism infections in patients with COVID-19:risk factors and outcomes
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作者 Yang Kun Bao-Qi Zeng +8 位作者 Qing-Qing Yang Meng Zhang Yun Lu Wen-Jing Li Su-Yu Gao Xuan-Xuan Wang Wen Hu Hong Cheng Feng Sun 《Medical Data Mining》 2023年第2期1-6,共6页
Background:Coronavirus disease 2019(COVID-19)has now spread to most countries and regions of the world.Risk factors associated with multi-drug resistant organism(MDRO)infections in patients with COVID-19 have not been... Background:Coronavirus disease 2019(COVID-19)has now spread to most countries and regions of the world.Risk factors associated with multi-drug resistant organism(MDRO)infections in patients with COVID-19 have not been well studied yet.In the present study,we aimed to identify the risk factors associated with the MDRO infections and their impact on in-hospital mortality of COVID-19 patients.Methods:This retrospective cohort study was conducted between December 2019 and April 2020 at two tertiary hospitals in Wuhan,China.Data of cases were collected through electronic medical records system.This study was focused on cases with bacterial culture records.Risk factors and outcomes associated with MDRO infections were analyzed using logistic regression model.Results:Of the 2891 patients,370 patients have bacterial culture results,and MDROs were isolated in 38 patients.Respiratory tract infections(67.3%)were the most common hospital acquired infections.Variables independently associated with MDRO infections were dyspnea at admission(odds ratio(OR)4.74;95%confidence interval(CI)2.06-10.88;P<0.001),intensive care unit(ICU)admission(OR 5.02;95%CI 1.99-12.63;P<0.01),and invasive mechanical ventilation(OR 5.13;95%CI 2.15-12.27;P<0.001),adjusted for age and gender.MDROs infection was also a significant risk factor of death for the patients,adjusted for age,gender,severity of illness,ICU admission and mechanical ventilation(OR 1.12,95%CI:0.43-2.96,P=0.817).Conclusion:In our study,dyspnea at admission,ICU admission and invasive mechanical ventilation were associated with the presence of MDRO infections,and clinicians should be alert in MDRO infections in COVID-19 hospitalized patients. 展开更多
关键词 COVID-19 multi-drug resistant organism INFECTION risk factor SARS-CoV-2
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Microplastics in Marine Environment: Occurrence, Distribution, and Extraction Methods in Marine Organisms
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作者 Boluwatife S. Olubusoye Peter Oni +6 位作者 Faustina Owusu Oluwatoyin Adekoya Acaye Ongwech Daniel A. Odogwu Oluwafemi Awolesi Ayobami Oje Beatrice Arwenyo 《Open Journal of Ecology》 2023年第12期931-955,共25页
The pervasive presence of microplastics in marine environments has raised significant concerns. This review addresses the pressing issue of microplastic pollution in marine ecosystems and its potential implications fo... The pervasive presence of microplastics in marine environments has raised significant concerns. This review addresses the pressing issue of microplastic pollution in marine ecosystems and its potential implications for both the environment and human health. It outlines the current state of microplastic occurrence, distribution, and extraction methods within marine organisms. Microplastics have emerged as a significant environmental concern due to their harmful effects on ecosystems and their potential human health risks. These particles infiltrate marine environments through runoff and atmospheric deposition, ultimately contaminating beaches and posing threats to marine life. Despite the gravity of this issue, there has been limited research on the presence and distribution of microplastics in marine organisms. This review aims to bridge this knowledge gap by comprehensively examining the occurrence, distribution, and various extraction methods used to detect microplastics in marine organisms. It emphasizes the urgent need for targeted measures to manage microplastic pollution, highlights the significant role of human activities in contributing to this problem, and underscores the importance of reducing human-induced pollution to safeguard marine ecosystems. While this paper contributes to the understanding of microplastic pollution in marine environments and underscores the critical importance of taking action to protect marine organisms and preserve our oceans for future generations, it also emphasizes that, in effectively tackling the microplastic problem, a well-coordinated approach is essential, involving research initiatives, policy adjustments, public involvement, and innovative technologies. Crucially, prompt and resolute responses must exist to counteract the escalating peril posed by microplastics to the oceans and the global environment. 展开更多
关键词 Microplastics Marine Environment Marine organisms Extraction Methods Ecological Impact Ocean Pollution
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Prevalence of Some World Health Organization Priority Organisms from an Abattoir at Kwata, Anambra State, Nigeria
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作者 Ruth Asikiya Afunwa Chudi Igweze Onyebuchi +4 位作者 Gbadamosi Francis Ayodele Eze Cynthia Adanna Egbuna Roselyn Ikegbune Chidozie Nwakaeze Emmanuel Amobi 《Advances in Microbiology》 2023年第8期420-433,共14页
The abattoir is one of the important sectors in the food industry, therefore the need for close monitoring of everything concerning it to minimize microbial contamination. The aim of the study is to identify bacteria ... The abattoir is one of the important sectors in the food industry, therefore the need for close monitoring of everything concerning it to minimize microbial contamination. The aim of the study is to identify bacteria listed as WHO priority organisms associated with meat from Kwata abattoir in Awka, Anambra state. The study was carried out over a three (3) months period from September to December 2022. Thirteen samples were collected from the floor, table, water, meat, knife and soil in the abattoir. The samples were cultured using streak and spread plate methods on MacConkey and Cetrimide agar. The isolates were identified with the following biochemical tests: catalase, oxidase, citrate and indole tests. Ampiclox levofloxacin, gentamicin, ofloxacin impenem ceftraixone, cefixime, cefuroxime and nitrofurantoin were used for sensitivity test following Kirby Bauer disc diffusion method and biofilm formation was determined using the tube method. The 75 isolates obtained were identified as follows;29.3% E. coli, 26.7% Klebsiella spp., 16% Proteus spp., and 28% Pseudomonas spp. The result of antibiotics sensitivity test interpreted using the European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints showed that (98%) of the isolates were resistant to the antibiotics used. Test for biofilm formation with 52 isolates showed 31 strong, 12 moderate and 9 weak biofilm formers. The result of this study confirms the presence of bacteria contaminants within the WHO priority list in the abattoir, as such there is need for improved handling of animals. Slaughtering, cleaning and distribution of meat should be done using aseptic procedures. . 展开更多
关键词 ABATTOIR WHO Priority organisms Antibiotic Resistance COMMUNITY
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Analysis of Multi-Drug Resistant Organism Surveillance and Antimicrobial Resistance Early Warning in a Hospital in 2022
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作者 Henggui Xu Qinggui Zhao 《Journal of Clinical and Nursing Research》 2023年第3期60-69,共10页
Objective:To determine the clinical distribution of multi-drug resistant organism(MDRO)in Jiangyan Hospital and the monitoring and warning of drug-resistance bacteria to provide an important basis for guiding the appl... Objective:To determine the clinical distribution of multi-drug resistant organism(MDRO)in Jiangyan Hospital and the monitoring and warning of drug-resistance bacteria to provide an important basis for guiding the application of broad-spectrum antibiotics in clinical treatment and reducing the occurrence of nosocomial infection.Methods:Retrospective screening and analysis were conducted on the pathogenic strains of hospitalized patients in our hospital in 2022.Results:A total of 2,769 strains of pathogenic bacteria and 390 strains of MDRO were detected and isolated in our hospital in 2022;the detection rate of MDRO was 14.08%.A total of 516 strains(18.64%)Klebsiella pneumoniae(KP)and 62 strains(12.02%)of carbapenem-resistant Klebsiella pneumoniae(CR-KP)were detected;436 strains(15.75%)of Escherichia coli(ECO)were detected,including 8 strains(1.83%)of CR-ECO;342 strains(12.35%)of Pseudomonas aeruginosa(PA)and 116 strains(33.92%)of CR-PA were detected;there were 194 strains(7.01%)of Acinetobacter baumannii(AB),among which 125 strains(64.43%)were CR-AB;there were 291 strains(10.51%)of Staphylococcus aureus,among which 79 strains(27.15%)of methicillin-resistant Staphylococcus aureus(MRSA)were detected;78 strains(2.82%)of Enterococcus faecalis were detected,and vancomycin-resistant enterococcus(VRE)was not detected.The first five MDROs were CR-AB,CR-PA,MRSA,CR-KP,and CR-ECO.The top five departments with the highest MDRO detection rate in 2022 were the ICU(37.44%),the Pulmonology Department(ward 13;31.03%),the Department of Rehabilitation(ward 5;6.67%),the Department of Neurosurgery(ward 11;4.62%),and the Department of General Surgery(ward 10;3.59 The resistance rate of antibacterial drugs is divided into four levels for early warning:30%to 40%,41%to 50%,51%to 75%,and 75%or more.Conclusion:Our hospital should strengthen the monitoring of antimicrobial resistance warning related to MDRO and the abuse of antimicrobial drugs.Based on the results of drug sensitivity and antimicrobial resistance warning,the use of antibiotics should be standardized in clinical practice to reduce nosocomial infection。 展开更多
关键词 Antimicrobial resistance ANTIBIOTICS Early warning Multi-drug resistant organism
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Assessing Earthworm Influence on Remediating Potentials of Soil Micro-Organisms, and Bioavailable Hydrocarbon Pollutant in the Niger Delta, Nigeria
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作者 Tambeke Nornu Gbarakoro Victoria Oluwaseyi Koshoffa Francis David Sikoki 《Journal of Geoscience and Environment Protection》 2023年第3期277-292,共16页
In the Niger Delta region of Nigeria, oil explorations and exploitations abound, causing environmental pollution with serious consequences on soil ecosystem and its biodiversity. In spite of the relationship between m... In the Niger Delta region of Nigeria, oil explorations and exploitations abound, causing environmental pollution with serious consequences on soil ecosystem and its biodiversity. In spite of the relationship between microbes and fauna in soil ecosystem, such that both organisms can metabolize certain range of petroleum hydrocarbon substrates with the fauna influencing the remediation potentials of bacteria, yet soil fauna is still not fully considered in bioremediation. The influence of earthworm;Lumbricus terrestris on the remediating potentials of soil bacteria in petroleum hydrocarbon contaminated soils was investigated. Eighteen pots were filled with 700 g of soil each, with nine treated with mixture of 3 levels crude oil and remediated with earthworm, while the other nine had no earthworm. The total petroleum hydrocarbon (TPH), soil physical, nutrient compositions, and TPH degrading bacteria biodiversity were determined before contamination or commencement of study and thirty days after. The results showed a decrease in TPH concentration of 55.58%, 62.57% and 67.07% in 1 ml, 2 ml and 3 ml crude oil contaminated soil, respectively. Species richness and abundance of bacteria organisms increased with high relative abundance in soils remediated with earthworms, hydrocarbon utilizing bacteria increased from less than 0.1 cfu/g to 0.4 cfu/g, and total heterotrophic bacteria 1.6 cfu/g at the end of the study. Earthworms increased rate of remediation potentials of bacteria, such that within 30 days post remediation treatment, 34.14% of reduced concentration was achieved over soil samples without earthworms at 3 ml, and 25.14% at 2 ml concentration. Reduction in pH levels in remediated soils was between 6.39 to 6.17 and 6.74 to 6.72 in unremediated soils, while moisture content was 6.73% to 6.77% unremediated and 5.85% to 6.62% in earthworm remediated soils. Total organic carbon, nitrates in soils inoculated with earthworms were lower in concentration than those without earthworms. Reverse was the case with potassium, phosphate and phosphorous concentrations which were above those without earthworms. Results indicate statistically, significant difference between reduction in TPH in earthworm remediated soils and unremediated soils, pointing out that earthworm is a good candidate for facilitation of bacteria remediation-petroleum hydrocarbon contamination. 展开更多
关键词 Petroleum Hydrocarbon Contamination Bacteria Biodiversity Soil Fauna Total Organic Carbon NITRATES
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Embryos - the evolutionary boundary of kingdoms of organisms
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作者 FUDa-li 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第1期65-66,i004,共3页
Bioevolution is still a main puzzle and attracts many scientists to research on it. Here I present that organisms have two impor- tant properties, definite structure and self-reproduction. Based on the number and conn... Bioevolution is still a main puzzle and attracts many scientists to research on it. Here I present that organisms have two impor- tant properties, definite structure and self-reproduction. Based on the number and connection of the structural units, organisms can be di- vided into three groups, unicellular, particellular and polycellular organisms. It can be called polycellular evolution that organisms evolve from unicellular, particellular to polycellular. Also it can be called diploid evolution that organisms evolve from haplobes to diplobes, two groups based on the reproductive differences. Some concepts like spore, zygote and embryos are redefined in the paper. Moreover, I present that embryos are the most important boundary of bioevolution and organisms can be divided into two evolutionary phases, the lower and the higher. The lower organisms, Kingdom Microbia (kingd. nov.), are inembryonate, which include Acytophyla (phyl. nov.), bacteria, protozoa, fungi and inembryonate algae. The higher organisms are embryonate and have two branches, Kingdom Plantae and Kingdom Animalia. Plantae are sessile and, autotrophic or sporogenic, which include higher plants and Nudembryophyta (phyl. nov.). Animalia are heterotrophic and, motile or gametogenic, which include all multicellular animals. The new system, which reflects the two important phases of bioevolu- tion and two branches of higher organisms, can really correct the problem of different kingdoms in different researches or by different re- searchers. 展开更多
关键词 Particellular organism Polycellular organism Kingdom Microbia kingd. nov. Kingdom Plantae Kingdom Animalia Phylum Nudembryophyta phyl. nov. Phylum Acytophyla phyl. nov.
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Biomass Fraction of Phosphate-Accumulating Organisms Grown in Anoxic and Aerobic Stages under Optimum Nitrate Concentration
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作者 王晓玲 李娜 +3 位作者 谢添 张芳 董利鹏 殷宝用 《Journal of Donghua University(English Edition)》 EI CAS 2014年第3期278-286,共9页
The effects of nitrate concentration on the capability of phosphorus uptake in the main anoxic stage were investigated.Meanwhile, the biomass fractions — heterotrophs, phosphateaccumulating organisms( PAOs),and nitri... The effects of nitrate concentration on the capability of phosphorus uptake in the main anoxic stage were investigated.Meanwhile, the biomass fractions — heterotrophs, phosphateaccumulating organisms( PAOs),and nitrifying organisms in a pilot-scale enhanced biological phosphorus removal( EBPR) system— were both experimentally and theoretically evaluated( from the mass balance calculations of organic matter, nitrogen and phosphorus),under optimum nitrate concentration in the main anoxic stage,in which the influent chemical oxygen demand( COD)concentration was stabilized at( 290 ± 10) mg·L- 1and the influent total phosphorus( TP) concentration was stabilized at( 7. 0 ± 0. 5)mg · L- 1. In long term operations,the process exhibited high performance in removing organic matter, nitrogen, and phosphorus. Approximately 46. 41% of organic matter,57. 21% of nitrogen,and 48. 14% of phosphorus were removed from the influent in the form of carbon dioxide,nitrogen gas,and polyphosphate,respectively. XH( heterotrophs),XPAO( PAOs),and XAUT( autotrophs) were regarded as the major organisms responsible for biomass production. The yield fractions of XHgrowth in the first anoxic,the second anoxic,and the aerobic stages were 10. 24%,19. 11%,and 19. 71%,respectively; the yield fractions of XPAO growth in the second anoxic and the aerobic stages were 24. 34% and19. 86%,respectively; the yield fraction of XAUTgrowth in the aerobic stage was 6. 74%. These results showed that XHand XPAOformed the major community. Moreover,a higher amount of XPAOgrowth on stored poly-hydroxyalkanoates( PHAs) under the anoxic condition was seen in this EBPR system for municipal wastewater treatment. 展开更多
关键词 biomass anoxic phosphorus uptake heterotrophs phosphate-accumulating organisms nitrifying organisms
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APPLICATION OF CLAYS TO REMOVAL OF RED TIDE ORGANISMS Ⅰ.COAGULATION OF RED TIDE ORGANISMS WITH CLAYS 被引量:27
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作者 俞志明 邹景忠 马锡年 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1994年第3期193-200,共8页
Coagulation of red tide organism cells with clays is discussed in theory and the effects of some fac-tors on it are studied.A quantitative model is presented which describes how the coagulation varies withpH in soluti... Coagulation of red tide organism cells with clays is discussed in theory and the effects of some fac-tors on it are studied.A quantitative model is presented which describes how the coagulation varies withpH in solution.According to the model,within the pH-range between pH<sub>zpc<sub>a</sub></sub>and pH<sub>zpc<sub>b</sub></sub>,V<sub>R</sub> is negativeand the coagulation is strong and strongest at pH=(pH<sub>zpc<sub>a</sub></sub>+pH<sub>zpc<sub>b</sub></sub>)/2.It is also demonstrated that whenthe diameter of clay particles is close to that of cells,the collision probability is low,resulting in weakercoagulation.The model results have been corroborated by experiments and so are scientific and theoreticalbases for application. 展开更多
关键词 COAGULATION RED TIDE organism REMOVAL CLAY
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Octoradiate Spiral Organisms in the Ediacaran of South China 被引量:29
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作者 TANG Feng YIN Chongyu +3 位作者 Stefan BENGTSON LIU Pengju WANG Ziqiang GAO Linzhi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第1期27-34,共8页
Shales of the Ediacaran Doushantuo Formation of South China contain a new disc-shaped macrofossil, Eoandromeda octobrachiata, characterized by eight spiral arms that were probably housed within an outer membrane. Alth... Shales of the Ediacaran Doushantuo Formation of South China contain a new disc-shaped macrofossil, Eoandromeda octobrachiata, characterized by eight spiral arms that were probably housed within an outer membrane. Although the presence of eight radiating structures entails a resemblance to cnidarian octocorals as well as to ctenophores, direct homologies with these extant groups are unlikely. Instead we bring attention to the helicospiral morphology of newly reported embryos from the Doushantuo Formation, suggesting that the long-sought adults of the Ediacaran embryonic metazoans have finally been found. 展开更多
关键词 Octoradiate spiral organism Eoandromeda octobrachiata EDIACARAN South China
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APPLICATION OF CLAYS TO REMOVAL OF RED TIDE ORGANISMS Ⅲ.THE COAGULATION OF KAOLIN ON RED TIDE ORGANISMS 被引量:16
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作者 俞志明 邹景忠 马锡年 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1995年第1期62-70,共9页
This article reports studies on the coagulation of kaolin(from Wuxian,Jiangsu,China)on various red tide organisms,and the observation for the first time that the coagulation of kaolin is much greaterthan that of montm... This article reports studies on the coagulation of kaolin(from Wuxian,Jiangsu,China)on various red tide organisms,and the observation for the first time that the coagulation of kaolin is much greaterthan that of montmorillonite so that kaolin is a more effective clay for removing red tide organisms.The authors’theoretical explanation and analysis by a mathematical-physical model prove that comparedto montmorillonite,kaolin has greater attraction for organism cells and therefore greater coagulation capabil-ity.This project’s studies on the effects of pH and acid-treatment show that the acid-treatment does not have much influence on the kaolin system;whereas the effect of pH on the kaolin system is the same asthat on the montmonrillonite system. 展开更多
关键词 KAOLIN COAGULATION red TIDE organism REMOVAL
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APPLICATION OF CLAYS TO REMOVAL OF RED TIDE ORGANISMS Ⅱ.COAGULATION OF DIFFERENT SPECIES OF RED TIDE ORGANISMS WITH MONTMORILLONITE AND EFFECT OF CLAY PRETREATMENT 被引量:25
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作者 俞志明 邹景忠 马锡年 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1994年第4期316-324,共9页
Study on the coagulation of four species of red tide organisms(Nitzschia pungens,Skeletonema costatum,Prorocentrum minimum and Noctiluca scintillans)with montmorillonite,and the effect ofmontmorillonite pretreatment... Study on the coagulation of four species of red tide organisms(Nitzschia pungens,Skeletonema costatum,Prorocentrum minimum and Noctiluca scintillans)with montmorillonite,and the effect ofmontmorillonite pretreatment on the coagulation shows that the capability for montmorillonite to coagu-late with them is in the order:N.pungens】S.costatum】P.minimum】N.scintillans.Thecoagulation is discussed from the aspects of the structure,shape,size,movement,habit,etc.of differ-ent species and the results are explained theoretically.The experimental results also indicate that the treat-ment of montmorillonite with acid can enhance its coagulating capability.This is due to the fact that Al(OH<sub>2</sub>)<sub>6</sub><sup>+3</sup>,exchanged from the clay lattice by hydrogen ion H<sup>+</sup>,forms hydroxy-aluminum polymers on thesurface of the montmorillonite.The hydroxy-aluminum polymers positively charge and increase the positivecharacteristic of the clay surface,and also serves as a bridge between adjacent surfaces of particles.Thesetwo functions 展开更多
关键词 montraorillonite PRETREATMENT red TIDE organismS REMOVAL coagulation.
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Effect of nitrification inhibitor DMPP on nitrogen leaching, nitrifying organisms, and enzyme activities in a rice-oilseed rape cropping system 被引量:27
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作者 LI Hua LIANG Xinqiang +3 位作者 CHEN Yingxu LIAN Yanfeng TIAN Guangming NI Wuzhong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第2期149-155,共7页
DMPP (3,4-dimethylpyrazole phosphate) has been used to reduce nitrogen (N) loss from leaching or denitrification and to improve N supply in agricultural land. However, its impact on soil nitrifying organisms and e... DMPP (3,4-dimethylpyrazole phosphate) has been used to reduce nitrogen (N) loss from leaching or denitrification and to improve N supply in agricultural land. However, its impact on soil nitrifying organisms and enzyme activities involved in N cycling is largely unknown. Therefore, an on-farm experiment, for two years, has been conducted, to elucidate the effects of DMPP on mineral N (NH4^+- N and NO3^--N) leaching, nitrifying organisms, and denitrifying enzymes in a rice-oilseed rape cropping system. Three treatments including urea alone (UA), urea + 1% DMPP (DP), and no fertilizer (CK), have been carded out. The results showed that DP enhanced the mean NH4^+-N concentrations by 19.1%-24.3%, but reduced the mean NO3^--N concentrations by 44.9%-56.6% in the leachate, under a two-year rice-rape rotation, compared to the UA treatment. The population of ammonia oxidizing bacteria, the activity of nitrate reductase, and nitrite reductase in the DP treatment decreased about 24.5%-30.9%, 14.9%-43.5%, and 14.7%-31.6%, respectively, as compared to the UA treatment. However, nitrite oxidizing bacteria and hydroxylamine reductase remained almost unaffected by DMPP. It is proposed that DMPP has the potential to either reduce NO3^--N leaching by inhibiting ammonia oxidization or N losses from denitrification, which is in favor of the N conversations in the rice-oilseed rape cropping system. 展开更多
关键词 DMPP (3 4-dimethylpyrazole phosphate) nitrification inhibitor nitrifying organisms nitrogen leaching soil enzymes
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Composting MSW and sewage sludge with effective complex microorganisms 被引量:18
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作者 XiBD LiuHL 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2002年第2期264-268,共5页
The effects of complex microorganisms in composting process of the municipal solid waste (MSW) and sludge were examined through inspecting biomass, temperature, oxygen consumption, organic mater, and C/N (the ratio of... The effects of complex microorganisms in composting process of the municipal solid waste (MSW) and sludge were examined through inspecting biomass, temperature, oxygen consumption, organic mater, and C/N (the ratio of carbon and nitrogen). The experimental results shows: complex microorganisms are effective to compose organic matter and speedup composting change into humus. 展开更多
关键词 effective complex microorganisms(ECM) temperature oxygen consumption organic matter C/N ratio
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Research proceedings on amphibian model organisms 被引量:6
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作者 Lu-Sha LIU Lan-Ying ZHAO +1 位作者 Shou-Hong WANG Jian-Ping JIANG 《Zoological Research》 CAS CSCD 2016年第4期237-245,共9页
Model organisms have long been important in biology and medicine due to their specific characteristics. Amphibians, especially Xenopus, play key roles in answering fundamental questions on developmental biology, regen... Model organisms have long been important in biology and medicine due to their specific characteristics. Amphibians, especially Xenopus, play key roles in answering fundamental questions on developmental biology, regeneration, genetics, and toxicology due to their large and abundant eggs, as well as their versatile embryos, which can be readily manipulated and developed in vivo. Furthermore, amphibians have also proven to be of considerable benefit in human disease research due to their conserved cellular developmental and genomic organization. This review gives a brief introduction on the progress and limitations of these animal models in biology and human disease research, and discusses the potential and challenge of Microhyla fissipes as a new model organism. 展开更多
关键词 AMPHIBIAN Model organism Life Science BIOMEDICINE Microhyla fissipes
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Screening on oil-decomposing microorganisms and application in organic waste treatment machine 被引量:9
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作者 LUYi-tong CHENXiao-bin ZHOUPei LIZhen-hong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第3期440-444,共5页
As an oil-decomposable mixture of two bacteria strains(Bacillus sp. and Pseudomonas sp.), Y3 was isolated after 50 d domestication under the condition that oil was used as the limited carbon source. The decomposing ra... As an oil-decomposable mixture of two bacteria strains(Bacillus sp. and Pseudomonas sp.), Y3 was isolated after 50 d domestication under the condition that oil was used as the limited carbon source. The decomposing rate by Y3 was higher than that by each separate individual strain, indicating a synergistic effect of the two bacteria. Under the conditions that T=25—40℃,pH=6—8, HRT(Hydraulic retention time)=36 h and the oil concentration at 0.1%, Y3 yielded the highest decomposing rate of 95.7 %. Y3 was also applied in an organic waste treatment machine and a certain rate of activated bacteria was put into the stuffing. A series of tests including humidity, pH, temperature, C/N rate and oil percentage of the stuffing were carried out to check the efficacy of oil-decomposition. Results showed that the oil content of the stuffing with inoculums was only half of that of the control. Furthermore, the bacteria were also beneficial to maintain the stability of the machine operating. Therefore, the bacteria mixture as well as the machines in this study could be very useful for waste treatment. 展开更多
关键词 oil-decomposing microorganism SCREENING application organic waste treatment machine decomposing rate
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Pollution monitoring of marine organisms grown in the Zhoushan Sea of China 被引量:6
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作者 Zhou Qixing, Zhu Yinmei Department of Environmental Sciences, Zhejiang Agricultural University, Hangzhou 310029, China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1997年第3期35-39,共5页
The sustainable regeneration of the biggest fishery resource in the Zhoushan Sea area of China has been adversely affected in recent years. Wastewater discharged into the marine ecosystem is the main source of pollut... The sustainable regeneration of the biggest fishery resource in the Zhoushan Sea area of China has been adversely affected in recent years. Wastewater discharged into the marine ecosystem is the main source of pollution. Affected organisms such as hairtail prawn, jellyfish, crab, laver and kelp were monitored, and the contributions and fluxes of three sort of pollutants(oils, Cr and phenol) from the expansion of rural enterprises in the Yangtze River valley, the Qiantang River valley, the Ningbo coastal area and the Zhoushan islands were calculated. More than 16 chemical pollutants were jointly responsible for the decrease in the yield and quality of marine organisms. Furthermore, combined contamination effects and their joint toxicity differed between summer and winter, because they were varied with different temperature, salinity, pH and E h. 展开更多
关键词 pollution monitoring marine environment affected organism.
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