The present study monitored bacterial succession,physicochemical properties,and volatile organic compounds(VOCs)changes in smoked chicken legs with modified atmosphere packaging(MAP,60% CO_(2) and 40%N_(2))during a 25...The present study monitored bacterial succession,physicochemical properties,and volatile organic compounds(VOCs)changes in smoked chicken legs with modified atmosphere packaging(MAP,60% CO_(2) and 40%N_(2))during a 25-day storage period at 4℃.After 15 days of storage,S erratia proteamaculans and Pseudomonas fragi became the predominant bacteria.Furthermore,physicochemical properties changed significantly,as evidenced by an increase in thiobarbituric acid reactive substances and b*(yellowness)value,and a decrease in hardness.A total of 65 VOCs were identified during storage.Correlation between bacterial succession and quality indicators(including VOCs and physicochemical properties)allowed the identification of 26 core dominant bacteria,including S.proteamaculans,Psychrobacter alimentarius,Pseudomonas putida,and Pseudomonas poae,which were positively related to spoilage VOCs(e.g.,1-octen-3-ol,1-pentanol,and 3-methyl-1-butanol)and could be defined as specific spoilage organisms(SSOs).The results of this study provide a systematic approach to predict SSOs in smoked chicken legs during storage,which can also provide a basis for product safety.展开更多
BACKGROUND Colonization with multidrug-resistant organisms(MDROs)is frequently observed in critically ill patients with liver cirrhosis admitted to intensive care units(ICUs).However,whether colonization directly lead...BACKGROUND Colonization with multidrug-resistant organisms(MDROs)is frequently observed in critically ill patients with liver cirrhosis admitted to intensive care units(ICUs).However,whether colonization directly leads to infections or adversely impacts clinical outcomes remains unclear.Clarifying this relationship may help deter-mine the prognostic significance of colonization in these patients.AIM To evaluate the clinical relevance of MDRO colonization and infection at ICU admission in patients with cirrhosis.METHODS This retrospective single-center cohort study included 107 ICU admissions of patients with liver cirrhosis at a tertiary care center(2018-2024).Colonization was assessed by rectal and nasal/pharyngeal swabs within 48 hours of ICU admission.Outcomes analyzed included MDRO infection during ICU stay,concordance between colonizing and infecting strains,organ support requirements,and 28-day transplant free survival.Multivariable logistic regression and Kaplan-Meier analyses were used to evaluate predictors of infection and mortality.RESULTS Nearly one-third(29.9%)of patients were colonized with MDROs on admission,more commonly in the acute-onchronic liver failure phenotype than those with acute decompensation(34.5 vs 10.0%,P=0.033).Although infections were established in the majority(85%)of cases,of which 17.6%due to MDROs,colonization alone did not independently predict these infections[odds ratio(OR)=2.18,P=0.383]nor influenced short-term mortality(OR=1.14,P=0.813).However,once MDRO infection occurred,an 82%concordance was observed between colonizing and infecting strains.MDRO infections,unlike colonization,significantly increased the need for organsupport interventions,including mechanical ventilation and vasopressor therapy and prolonged ICU stays.Only severity of organ dysfunction,quantified by the Sequential Organ Failure Assessment score,independently predicted 28-day mortality(OR=1.38,P=0.024).CONCLUSION MDRO colonization at ICU admission is frequent among critically ill patients with cirrhosis,particularly those with acute-on-chronic liver failure.While colonization alone does not predict infection or early mortality,its clinical value emerges in guiding empirical antibiotic treatment once infection is suspected.Ultimately,short-term survival appears to be more strongly influenced by the severity of organ failure than by either MDRO colonization or infection.展开更多
New pollutants have become a significant concern in China's efforts toward ecological and environmental protection.Trichloromethane(TCM,CHCl_3),one of these new pollutants,is primarily released into soil and groun...New pollutants have become a significant concern in China's efforts toward ecological and environmental protection.Trichloromethane(TCM,CHCl_3),one of these new pollutants,is primarily released into soil and groundwater through various industrial activities.Over the past four decades,researchers have consistently focused on the remediation of TCM-contaminated soil and groundwater using microorganisms and iron-based materials,which hold significant potential for practical application.Understanding the remediation process and the factors influencing TCM degradation through these two methods is crucial for advancing both theoretical research and practical implementation.This review focuses on the degradation mechanisms of TCM in soil and groundwater by microorganisms and iron-based materials.It summarizes the active microorganisms and modified iron-based materials with high TCM degradation capabilities,discusses enhancement measures for both methods in the remediation process,and finally,outlines the challenges faced by these methods.The goal is to provide theoretical references for efficient remediation of TCM-contaminated soil and groundwater.展开更多
[ Objective] The study aimed to supply important basis for developing environment-friendly pesticides with myricetin and crude extract of Myrica rubra leaves as effective components. [ Method] According to ＂Test guid...[ Objective] The study aimed to supply important basis for developing environment-friendly pesticides with myricetin and crude extract of Myrica rubra leaves as effective components. [ Method] According to ＂Test guidelines for environmental safety evaluation on chemical pesticides＂, the toxicity of myricetin and crude extract of M. rubra leaves on non-target organisms was determined and the safety evaluation was carried out. [Result] MyriceUn and crude extract of M. rubra leaves had low toxicity on non-target organisms, such as earthworm, silkworm and soil microbes. Myricetin showed low toxicity and the crude extract of M. rubra leaves showed middle toxicity on tadpole. The high-concentration crude extract of M. rubra leaves had some antifeedant effect on silkworm. [ Conclusion] Myricetin and crude extract of M. rubra leaves had low toxicity on non-tar- get organisms in environment and they were relatively safe.展开更多
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
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 of montmorillonite pretrea...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 of montmorillonite pretreatment on the coagulation shows that the capability for montmorillonite to coagulate with them is in the order: N. pungens > S. costatum > P. minimum > N. scintillans. The coagulation is discussed from the aspects of the structure, shape, size, movement, habit, etc. of different species and the results are explained theoretically. The experimental results also indicate that the treatment of montmorillonite with acid can enhance its coagulating capability. This is due to the fact that A1(OH2)6+3, exchanged from the clay lattice by hydrogen ion H+, forms hydroxy-aluminum polymers on the surface of the montmorillonite. The hydroxy-aluminum polymers positively charge and increase the positive characteristic of the clay surface, and also serves as a bridge between adjacent surfaces of particles. These two functions enhance the montmorillonite's capability for coagulating with the organism cells.展开更多
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
Titanium dioxide nanoparticles(TiO_2 NPs) are one of the most widely used nanomaterials in the consumer products, agriculture, and energy sectors. Their large demand and widespread applications will inevitably cause d...Titanium dioxide nanoparticles(TiO_2 NPs) are one of the most widely used nanomaterials in the consumer products, agriculture, and energy sectors. Their large demand and widespread applications will inevitably cause damage to organisms and ecosystems. A better understanding of TiO_2 NP toxicity in living organisms may promote risk assessment and safe use practices of these nanomaterials. This review summarizes the toxic effects of TiO_2 NPs on multiple taxa of microorganisms, algae, plants, invertebrates, and vertebrates. The mechanism of TiO_2 NP toxicity to organisms can be outlined in three aspects: The Reactive Oxygen Species(ROS)produced by TiO_2 NPs following the induction of electron–hole pairs; cell wall damage and lipid peroxidation of the cell membrane caused by NP-cell attachment by electrostatic force owing to the large surface area of TiO_2 NPs; and TiO_2 NP attachment to intracellular organelles and biological macromolecules following damage to the cell membranes.展开更多
BACKGROUND Intensive care unit(ICU)patients are critically ill and have low immunity.They will undergo various trauma medical procedures during diagnosis and treatment.The use of high-dose hormones and broad-spectrum ...BACKGROUND Intensive care unit(ICU)patients are critically ill and have low immunity.They will undergo various trauma medical procedures during diagnosis and treatment.The use of high-dose hormones and broad-spectrum antibiotics will increase the incidence of nosocomial infection in ICU patients.Therefore,it is necessary to explore the causes of nosocomial infection in ICU and provide basis for the prevention and control of nosocomial infection in ICU.AIM To explore major pathogens of nosocomial infection in ICUs,methods of detection and drug resistance trends.METHODS Risk factors of multidrug-resistant infection were analyzed to provide a basis for clinical rational use of antimicrobial drugs in the ICU.These findings were used to standardize rational use of antimicrobial agents.BD PhoenixTM100 automatic bacterial identification analyzer was used to for cell identification in specimens collected from the ICU between January 2016 and December 2019.Drug sensitivity tests were carried out and drug resistance trends were analyzed using the optical disc diffusion method.Odds ratios and corresponding 95%CI of independent variables were calculated using a logistic regression model.Backward elimination(trend=0.1)was used as an inclusion criterion for multivariate analysis.All data were analyzed using SPSS version 22.0,and P<0.05 was considered statistically significant.RESULTS We collected 2070 samples from ICU patients between January 2016 and December 2019.Sample types comprised sputum(1139 strains,55.02%),blood(521 strains,25.17%),and drainage fluid(117 strains,5.65%).A total of 1051 strains of major pathogens,including Acinetobacter baumannii,Escherichia coli(E.coli),Pseudomonas aeruginosa(P.aeruginosa),Klebsiella pneumoniae(K.pneumoniae)and Staphylococcus aureus,were detected,with a detection rate of 35.97%(378/1051).Most of these strains were resistant to antibiotics.Detection rate of E.coli was 21.79%(229/1051),and it was generally sensitive to many antimicrobial drugs.Detection rate of P.aeruginosa was 24.74%(260/1051),and showed low sensitivity to most antibiotics.Detection rate of K.pneumoniae was 9.42%(99/1051),which was generally resistant to multiple antimicrobial drugs and resistant forms.K.pneumoniae was resistant to imipenem for approximate 4 years,and showed a 19.9%(19/99)and 20.20%(20/99)rate of meropenem resistance.Logistic analysis showed that mechanical ventilation and ureteral intubation were risk factors for multidrug-resistant bacterial infections.CONCLUSION This study showed a high incidence of ICU infections.Mechanical ventilation and urine tube intubation were risk factors for infection with multidrug-resistant bacteria.展开更多
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
Objective To study the possibility of removing nitrogen, phosphorus, and organic pollutants using seeding type immobilized microorganisms. Methods Lakes P and M in Wuhan were chosen as the objects to study the removal...Objective To study the possibility of removing nitrogen, phosphorus, and organic pollutants using seeding type immobilized microorganisms. Methods Lakes P and M in Wuhan were chosen as the objects to study the removal of nitrogen, phosphorus, and organic pollutants with the seeding type immobilized microorganisms. Correlations between the quantity of heterotrophic bacteria and the total nitrogen （TN）, total phosphorus （TP）, and total organic carbon （TOC） in the two lakes were studied. The dominant bacteria were detected, inoculated to the sludge and acclimated by increasing nitrogen, phosphorus and decreasing carbon source in an intermittent, time-controlled and fixed-quantity way. The bacteria were then used to prepare the seeding type immobilized microorganisms, selecting diatomite as the adsorbent cartier. The ability and influence factors of removing nitrogen, phosphorus, and organic pollutant from water samples by the seeding type immobilized microorganisms were studied. Results The coefficients of the heterotrophic bacterial quantity correlated with TOC, TP, and TN were 0.9143, 0.8229, 0.7954 in Lake P and 0.9168, 0.7187, 0.6022 in Lake M. Ten strains of dominant heterotrophic bacteria belonging to Pseudomonas, Coccus, Aeromonas, Bacillus, and Enterobateriaceae, separately, were isolated. The appropriate conditions for the seeding type immobilized microorgansims in purifying the water sample were exposure time=24 h, pH=7.0-8.0, and quantity of the immobilized microorganisms=0.75-1g/50 mL. The removal rates of TOC, TP, and TN under the above conditions were 80.2%, 81.6%, and 86.8%, respectively. Conclusion The amount of heterotrophic bacteria in the two lakes was correlated with TOC, TP, and TN. These bacteria could be acclimatized and prepared for the immobilized microorganisms which could effectively remove nitrogen, phosphorus, and mixed organic pollutants in the water sample.展开更多
With physical method of micro-gap gas discharge, a large amount of hydroxyl radical can be produced in 20t/h pilot-scale system using the ionization of 02 and H2O. In this paper, the effect of biochemistry of hydroxyl...With physical method of micro-gap gas discharge, a large amount of hydroxyl radical can be produced in 20t/h pilot-scale system using the ionization of 02 and H2O. In this paper, the effect of biochemistry of hydroxyl radicals on introduced organisms in ballast water was experimentally investigated. The results indicate that the contents of chlorophyl-a, chlorophyl-b, chlorophyl-c and carotenoid are decreased by 35%-4% within 8.0s and further to the lowest limit of test 5 minutes. In addition, the main reasons of cell death are the lipid peroxidation, the strong destruction to the monose, amylose, protein, DNA and RNA of cell, and damage in CAT, POD and SOD of antioxidant enzyme system.展开更多
Until recently,potassium(K)has not received considerable attention because of the general belief that soils contain ample amounts of this element.In addition,low rates of K fertilizer application in agriculture have l...Until recently,potassium(K)has not received considerable attention because of the general belief that soils contain ample amounts of this element.In addition,low rates of K fertilizer application in agriculture have led to rapid depletion of K in the rhizosphere soil in many underdeveloped countries.This results in various negative impacts,including preventing optimum utilization of applied nitrogen and phosphorus fertilizers.To compensate for these losses,massive use of K fertilizers in agriculture has been suggested.Potassium fertilizers are manufactured from rock minerals,particularly sylvite(KCl)and carnallite(KCl·MgCl2·6H2O).Unfortunately,to date,there is no cost-effective technology available for converting rock minerals into potassic fertilizers.Potassium-solubilizing microorganisms(KSMs)can release K from soil/minerals into plant-available forms,which could be a sustainable option.The possibility of using KSMs as efficient biofertilizers to improve crop production has been increasingly highlighted by researchers.In this review,the existing forms of K in soils and their availability and dynamic equilibrium are discussed.In addition,different K fertilizers and their advantages and disadvantages for crops are described.Furthermore,the microorganisms usually reported as K solubilizers,the research progress on KSMs,and future insights on the use of these KSMs in agriculture are reviewed.Screening and analyses of the published literature show that organic acid production is the common mechanism of K solubilization by bacteria and fungi.This review may serve as a proposal for the future research avenues identified here.展开更多
Glycogen accumulating organisms(GAOs) are closely related to the deterioration of enhanced biological phosphorus removal systems. However, the metabolic mechanisms that drive GAOs remain unclear. Here, the two-thirds ...Glycogen accumulating organisms(GAOs) are closely related to the deterioration of enhanced biological phosphorus removal systems. However, the metabolic mechanisms that drive GAOs remain unclear. Here, the two-thirds supernatant of a reactor were decanted following the anaerobic period to enrich GAOs. Long-term monitoring demonstrated that the system was stable and exhibited typical characteristics of GAOs metabolism. Acetate was completely consumed after 60 min of the anaerobic phase. The level of glycogen decreased from 0.20 to 0.14 g/gSS during the anaerobic phase, whereas the level of glycogen significantly increased to 0.21g/gSS at the end of the aerobic period. Moreover, there was almost no phosphate release and absorption in the complete periods, thus confirming the successful construction of a GAOs enrichment system. Microbial community analysis demonstrated that Ca. Contendobacter was among the core functional genera and showed the highest activity among all of the communities. Furthermore, our study is the first to identify the involvement of the ethyl-malonyl-CoA pathway in the synthesis of polyhydroxyvalerate via croR, ccr, ecm, mcd, mch and mcl genes. The Embden-Meyerhof-Parnas(EMP) pathway was preferentially used via glgP. Furthermore, the glyoxylate cycle was the main source of ATP under anaerobic conditions, whereas the tricarboxylic acid cycle provided ATP under aerobic conditions. aceA and mdh appeared to be major modulators of the glyoxylate pathway for controlling energy flow. Collectively, our findings not only revealed the crucial metabolic mechanisms in a GAOs enrichment system but also provided insights into the potential application of Ca. Contendobacter for wastewater treatment.展开更多
With the physical method of micro-gap gas discharge, OH. radicals were produced by the ionization of O2 in air and H2O in the gaseous state, in order to explore more effective method totreat the ship＇s ballast water....With the physical method of micro-gap gas discharge, OH. radicals were produced by the ionization of O2 in air and H2O in the gaseous state, in order to explore more effective method totreat the ship＇s ballast water. The surface morphology of Al2O3 dielectric layer was analysed using Atomic Force Microscopy （AFM）, where the size of Al2O3 particles was in the range of 2 μm to 5 μm. At the same time, the biochemical effect of hydroxyl radicals on the introduced organisms and the quality of ship＇s ballast water were studied. The results indicate that the main reasons of cell death are lipid peroxide and damage of the antioxidant enzyme system in Catalase （CAT）, Peroxidase （POD） and Superoxide dismutase （SOD）. In addition, the quality of the ballast water was greatly improved.展开更多
Temperature is an important physical factor, which strongly influences biomass and metabolic activity. In this study, the effects of temperature on the anoxic metabolism of nitrite （NO2） to nitrous oxide （N2O） by ...Temperature is an important physical factor, which strongly influences biomass and metabolic activity. In this study, the effects of temperature on the anoxic metabolism of nitrite （NO2） to nitrous oxide （N2O） by polyphosphate accumulating organisms, and the process of the accumulation of N2O （during nitrite reduction）, which acts as an electron acceptor, were investigated using 91% ：e 4% Candidatus Accumulibacterphosphatis sludge. The results showed that N2O is accumulated when Accumulibacter first utilize nitrite instead of oxygen as the sole electron acceptor during the denitrifying phosphorus removal process. Properties such as nitrite reduction rate, phosphorus uptake rate, N2O reduction rate, and polyhydroxyalkanoate degradation rate were all influenced by temperature variation （over the range from 10 to 30℃ reaching maximum values at 25℃）. The reduction rate of N2O by N2O reductase was more sensitive to temperature when N2O was utilized as the sole electron acceptor instead of NO2, and the N2O reduction rates, ranging from 0.48 to 3.53 N2O-N/（hr.g VSS）, increased to 1.45 to 8.60 mg N2O-N/（hr·g VSS）. The kinetics processes for temperature variation of 10 to 30℃ were （01 = 1.140-1.216 and θ2 = 1.139-1.167）. In the range of 10℃ to 30℃, almost all of the anoxic stoichiometry was sensitive to temperature changes. In addition, a rise in N2O reduction activity leading to a decrease in N2O accumulation in long term operations at the optimal temperature （27℃ calculated by the Arrhenius model）.展开更多
Sludge dewatering and treatment may cost as much as the wastewater treatment.Usually large proportion of the pollutants in wastewater is organic.They are attacked by saprophytic microorganisms,i.e.organisms that feed ...Sludge dewatering and treatment may cost as much as the wastewater treatment.Usually large proportion of the pollutants in wastewater is organic.They are attacked by saprophytic microorganisms,i.e.organisms that feed upon dead organic matter.Activity of organisms causes decomposition of organic matter and destroys them,where the bacteria convert the organic matter or other constituents in the wastewater to new cells,water,gases and other products.Demolition activities,including renovation/remodeling works and complete or selective removal/demolishing of existing structures either by man-made processes or by natural disasters,create an extensive amount of wastes.These demolition wastes are characterized as heterogeneous mixtures of building materials that are usually contaminated with chemicals and dirt.In developing countries, it is estimated that demolition wastes comprise 20%to 30%of the total annual solid wastes.In Egypt,the daily quantity of construction and demolition(C&D) waste has been estimated as 10 000 tones.That is equivalent to one third of the total daily municipal solid wastes generated per day in Egypt.The zabbaliin have since expanded their activities and now take the waste they collect back to their garbage villages where it is sorted into recyclable components:paper,plastics, rags,glass,metal and food.The food waste is fed to pigs and the other items are sold to recycling centers.This paper summarizes the wastewater and solid wastes management in Egypt now and future.展开更多
In environmental risk assessments（ERA）, biomarkers have been widely used as an early warning signal of environmental contamination. However, biomarker responses have limitation due to its low relevance to adverse ou...In environmental risk assessments（ERA）, biomarkers have been widely used as an early warning signal of environmental contamination. However, biomarker responses have limitation due to its low relevance to adverse outcomes（e.g., fluctuations in community structure, decreases in population size, and other similar ecobiologically relevant indicators of community structure and function）. To mitigate these limitations, the concept of adverse outcome pathways（AOPs） was developed. An AOP is an analytical, sequentially progressive pathway that links a molecular initiating event（MIE） to an adverse outcome. Recently, AOPs have been recognized as a potential informational tool by which the implications of molecular biomarkers in ERA can be better understood. To demonstrate the utility of AOPs in biomarker-based ERA, here we discuss a series of three different biological repercussions caused by exposure to benzo（a）pyrene（Ba P）, silver nanoparticles（Ag NPs）, and selenium（Se）. Using mainly aquatic invertebrates and selected vertebrates as model species, we focus on the development of the AOP concept. Aquatic organisms are suitable bioindicator species whose entire lifespans can be observed over a short period; moreover, these species can be studied on the molecular and population levels.Also, interspecific differences between aquatic organisms are important to consider in an AOP framework, since these differences are an integral part of the natural environment.The development of an environmental pollutant-mediated AOP may enable a better understanding of the effects of environmental pollutants in different scenarios in the diverse community of an ecosystem.展开更多
Comprehending the diversity of the regenerative potential across metazoan phylogeny represents a fundamental challenge in biology. Invertebrates like Hydra and planarians exhibit amazing feats of regeneration, in whic...Comprehending the diversity of the regenerative potential across metazoan phylogeny represents a fundamental challenge in biology. Invertebrates like Hydra and planarians exhibit amazing feats of regeneration, in which an entire organism can be restored t^om minute body segments. Vertebrates like teleost fish and amphibians can also regrow large sections of the body. While this regenerative capacity is greatly attenuated in mammals, there are portions of major organs that remain regenerative. Regardless of the extent, there are common basic strategies to regeneration, including activation of adult stem cells and proliferation of differentiated cells. Here, we discuss the cellular features and molecular mechanisms that are involved in regeneration in different model organisms, including 14ydra, planarians, zebrafish and newts as well as in several mammalian organs.展开更多
The paper elaborates the features and superiority of applying multimedia technology to aquatic organisms in a Science and Life Technology course. The augmented reality application of multimedia technology in aquatic o...The paper elaborates the features and superiority of applying multimedia technology to aquatic organisms in a Science and Life Technology course. The augmented reality application of multimedia technology in aquatic organisms’ instruction has its own features, teaching information capacity, interactive user interface. The paper concludes the superiority of Unity and Vuforia AR instruction from five perspectives;meanwhile, the paper elaborates its disadvantages. An AR-based instruction attitude questionnaire was conducted at the end of the experiment to obtain learners’ perspectives of the system. Learners in AR approach demonstrate higher motivation and concentrate their attention on the learning tasks. Learners showed more positive attitude in willingness to use the AR-based instruction to improve learning interests. This study provided insights for better understanding the design, theory and practice of e-learning through augmented reality technology.展开更多
基金funded by the National Natural Science Foundation of China(U22A20547)the Major Science and Technology Projects of Heilongjiang Province(2021ZX12B05 and 2020ZX07B02)。
文摘The present study monitored bacterial succession,physicochemical properties,and volatile organic compounds(VOCs)changes in smoked chicken legs with modified atmosphere packaging(MAP,60% CO_(2) and 40%N_(2))during a 25-day storage period at 4℃.After 15 days of storage,S erratia proteamaculans and Pseudomonas fragi became the predominant bacteria.Furthermore,physicochemical properties changed significantly,as evidenced by an increase in thiobarbituric acid reactive substances and b*(yellowness)value,and a decrease in hardness.A total of 65 VOCs were identified during storage.Correlation between bacterial succession and quality indicators(including VOCs and physicochemical properties)allowed the identification of 26 core dominant bacteria,including S.proteamaculans,Psychrobacter alimentarius,Pseudomonas putida,and Pseudomonas poae,which were positively related to spoilage VOCs(e.g.,1-octen-3-ol,1-pentanol,and 3-methyl-1-butanol)and could be defined as specific spoilage organisms(SSOs).The results of this study provide a systematic approach to predict SSOs in smoked chicken legs during storage,which can also provide a basis for product safety.
基金approved by the Institutional Review Board of the University Hospital Centre Zagreb(Approval No:02/013 AG).
文摘BACKGROUND Colonization with multidrug-resistant organisms(MDROs)is frequently observed in critically ill patients with liver cirrhosis admitted to intensive care units(ICUs).However,whether colonization directly leads to infections or adversely impacts clinical outcomes remains unclear.Clarifying this relationship may help deter-mine the prognostic significance of colonization in these patients.AIM To evaluate the clinical relevance of MDRO colonization and infection at ICU admission in patients with cirrhosis.METHODS This retrospective single-center cohort study included 107 ICU admissions of patients with liver cirrhosis at a tertiary care center(2018-2024).Colonization was assessed by rectal and nasal/pharyngeal swabs within 48 hours of ICU admission.Outcomes analyzed included MDRO infection during ICU stay,concordance between colonizing and infecting strains,organ support requirements,and 28-day transplant free survival.Multivariable logistic regression and Kaplan-Meier analyses were used to evaluate predictors of infection and mortality.RESULTS Nearly one-third(29.9%)of patients were colonized with MDROs on admission,more commonly in the acute-onchronic liver failure phenotype than those with acute decompensation(34.5 vs 10.0%,P=0.033).Although infections were established in the majority(85%)of cases,of which 17.6%due to MDROs,colonization alone did not independently predict these infections[odds ratio(OR)=2.18,P=0.383]nor influenced short-term mortality(OR=1.14,P=0.813).However,once MDRO infection occurred,an 82%concordance was observed between colonizing and infecting strains.MDRO infections,unlike colonization,significantly increased the need for organsupport interventions,including mechanical ventilation and vasopressor therapy and prolonged ICU stays.Only severity of organ dysfunction,quantified by the Sequential Organ Failure Assessment score,independently predicted 28-day mortality(OR=1.38,P=0.024).CONCLUSION MDRO colonization at ICU admission is frequent among critically ill patients with cirrhosis,particularly those with acute-on-chronic liver failure.While colonization alone does not predict infection or early mortality,its clinical value emerges in guiding empirical antibiotic treatment once infection is suspected.Ultimately,short-term survival appears to be more strongly influenced by the severity of organ failure than by either MDRO colonization or infection.
基金financially supported by the National Natural Science Foundation of China(Nos.42177239 and 41991330)the“14th Five Year Plan”of Independent Deployment Project of Nanjing Institute of Soil Research,Chinese Academy of Sciences(No.ISSASIP2213)。
文摘New pollutants have become a significant concern in China's efforts toward ecological and environmental protection.Trichloromethane(TCM,CHCl_3),one of these new pollutants,is primarily released into soil and groundwater through various industrial activities.Over the past four decades,researchers have consistently focused on the remediation of TCM-contaminated soil and groundwater using microorganisms and iron-based materials,which hold significant potential for practical application.Understanding the remediation process and the factors influencing TCM degradation through these two methods is crucial for advancing both theoretical research and practical implementation.This review focuses on the degradation mechanisms of TCM in soil and groundwater by microorganisms and iron-based materials.It summarizes the active microorganisms and modified iron-based materials with high TCM degradation capabilities,discusses enhancement measures for both methods in the remediation process,and finally,outlines the challenges faced by these methods.The goal is to provide theoretical references for efficient remediation of TCM-contaminated soil and groundwater.
基金Supported by Major Program in Zhejiang Science and Technology Department(2008C22G2100038)Emerging Artists Project in Zhejiang Province(21000037)~~
文摘[ Objective] The study aimed to supply important basis for developing environment-friendly pesticides with myricetin and crude extract of Myrica rubra leaves as effective components. [ Method] According to ＂Test guidelines for environmental safety evaluation on chemical pesticides＂, the toxicity of myricetin and crude extract of M. rubra leaves on non-target organisms was determined and the safety evaluation was carried out. [Result] MyriceUn and crude extract of M. rubra leaves had low toxicity on non-target organisms, such as earthworm, silkworm and soil microbes. Myricetin showed low toxicity and the crude extract of M. rubra leaves showed middle toxicity on tadpole. The high-concentration crude extract of M. rubra leaves had some antifeedant effect on silkworm. [ Conclusion] Myricetin and crude extract of M. rubra leaves had low toxicity on non-tar- get organisms in environment and they were relatively safe.
基金National Natural Science Foundation of China(No.51308253)Jilin Province Science and Technology Development Projects,China(No.20130522076JH)
文摘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.
基金the Chinese postdoctoral fund Natural Science fund of Shandong province No 93E0157 and State Major Besearch project (PD-B6-7-2)
文摘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 of montmorillonite pretreatment on the coagulation shows that the capability for montmorillonite to coagulate with them is in the order: N. pungens > S. costatum > P. minimum > N. scintillans. The coagulation is discussed from the aspects of the structure, shape, size, movement, habit, etc. of different species and the results are explained theoretically. The experimental results also indicate that the treatment of montmorillonite with acid can enhance its coagulating capability. This is due to the fact that A1(OH2)6+3, exchanged from the clay lattice by hydrogen ion H+, forms hydroxy-aluminum polymers on the surface of the montmorillonite. The hydroxy-aluminum polymers positively charge and increase the positive characteristic of the clay surface, and also serves as a bridge between adjacent surfaces of particles. These two functions enhance the montmorillonite's capability for coagulating with the organism cells.
文摘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.
基金supported by the National Natural Science Foundation of China (Nos.21607043,21577032)the Youth Innovation Promotion Association,Chinese Academy of Sciences (No.2018054)+1 种基金the Fundamental Research Funds for the Central Universities (Nos.2016ZZD06,2018ZD11)the Open Project of Key Laboratory of Environmental Biotechnology,CAS (No.kf2016009)
文摘Titanium dioxide nanoparticles(TiO_2 NPs) are one of the most widely used nanomaterials in the consumer products, agriculture, and energy sectors. Their large demand and widespread applications will inevitably cause damage to organisms and ecosystems. A better understanding of TiO_2 NP toxicity in living organisms may promote risk assessment and safe use practices of these nanomaterials. This review summarizes the toxic effects of TiO_2 NPs on multiple taxa of microorganisms, algae, plants, invertebrates, and vertebrates. The mechanism of TiO_2 NP toxicity to organisms can be outlined in three aspects: The Reactive Oxygen Species(ROS)produced by TiO_2 NPs following the induction of electron–hole pairs; cell wall damage and lipid peroxidation of the cell membrane caused by NP-cell attachment by electrostatic force owing to the large surface area of TiO_2 NPs; and TiO_2 NP attachment to intracellular organelles and biological macromolecules following damage to the cell membranes.
基金Supported by Drug resistance trend analysis and prevention and control of main pathogens in tertiary hospitals of Hebei Provincial Department of health,No.20210845Analysis of drug and drug resistance trend and prevention and control of pathogens in major general hospitals of Baoding science and technology support plan project,No.17zf79.
文摘BACKGROUND Intensive care unit(ICU)patients are critically ill and have low immunity.They will undergo various trauma medical procedures during diagnosis and treatment.The use of high-dose hormones and broad-spectrum antibiotics will increase the incidence of nosocomial infection in ICU patients.Therefore,it is necessary to explore the causes of nosocomial infection in ICU and provide basis for the prevention and control of nosocomial infection in ICU.AIM To explore major pathogens of nosocomial infection in ICUs,methods of detection and drug resistance trends.METHODS Risk factors of multidrug-resistant infection were analyzed to provide a basis for clinical rational use of antimicrobial drugs in the ICU.These findings were used to standardize rational use of antimicrobial agents.BD PhoenixTM100 automatic bacterial identification analyzer was used to for cell identification in specimens collected from the ICU between January 2016 and December 2019.Drug sensitivity tests were carried out and drug resistance trends were analyzed using the optical disc diffusion method.Odds ratios and corresponding 95%CI of independent variables were calculated using a logistic regression model.Backward elimination(trend=0.1)was used as an inclusion criterion for multivariate analysis.All data were analyzed using SPSS version 22.0,and P<0.05 was considered statistically significant.RESULTS We collected 2070 samples from ICU patients between January 2016 and December 2019.Sample types comprised sputum(1139 strains,55.02%),blood(521 strains,25.17%),and drainage fluid(117 strains,5.65%).A total of 1051 strains of major pathogens,including Acinetobacter baumannii,Escherichia coli(E.coli),Pseudomonas aeruginosa(P.aeruginosa),Klebsiella pneumoniae(K.pneumoniae)and Staphylococcus aureus,were detected,with a detection rate of 35.97%(378/1051).Most of these strains were resistant to antibiotics.Detection rate of E.coli was 21.79%(229/1051),and it was generally sensitive to many antimicrobial drugs.Detection rate of P.aeruginosa was 24.74%(260/1051),and showed low sensitivity to most antibiotics.Detection rate of K.pneumoniae was 9.42%(99/1051),which was generally resistant to multiple antimicrobial drugs and resistant forms.K.pneumoniae was resistant to imipenem for approximate 4 years,and showed a 19.9%(19/99)and 20.20%(20/99)rate of meropenem resistance.Logistic analysis showed that mechanical ventilation and ureteral intubation were risk factors for multidrug-resistant bacterial infections.CONCLUSION This study showed a high incidence of ICU infections.Mechanical ventilation and urine tube intubation were risk factors for infection with multidrug-resistant bacteria.
文摘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.
基金This work was supported by the National Natural Science Foundation of China (No. 30400346)
文摘Objective To study the possibility of removing nitrogen, phosphorus, and organic pollutants using seeding type immobilized microorganisms. Methods Lakes P and M in Wuhan were chosen as the objects to study the removal of nitrogen, phosphorus, and organic pollutants with the seeding type immobilized microorganisms. Correlations between the quantity of heterotrophic bacteria and the total nitrogen （TN）, total phosphorus （TP）, and total organic carbon （TOC） in the two lakes were studied. The dominant bacteria were detected, inoculated to the sludge and acclimated by increasing nitrogen, phosphorus and decreasing carbon source in an intermittent, time-controlled and fixed-quantity way. The bacteria were then used to prepare the seeding type immobilized microorganisms, selecting diatomite as the adsorbent cartier. The ability and influence factors of removing nitrogen, phosphorus, and organic pollutant from water samples by the seeding type immobilized microorganisms were studied. Results The coefficients of the heterotrophic bacterial quantity correlated with TOC, TP, and TN were 0.9143, 0.8229, 0.7954 in Lake P and 0.9168, 0.7187, 0.6022 in Lake M. Ten strains of dominant heterotrophic bacteria belonging to Pseudomonas, Coccus, Aeromonas, Bacillus, and Enterobateriaceae, separately, were isolated. The appropriate conditions for the seeding type immobilized microorgansims in purifying the water sample were exposure time=24 h, pH=7.0-8.0, and quantity of the immobilized microorganisms=0.75-1g/50 mL. The removal rates of TOC, TP, and TN under the above conditions were 80.2%, 81.6%, and 86.8%, respectively. Conclusion The amount of heterotrophic bacteria in the two lakes was correlated with TOC, TP, and TN. These bacteria could be acclimatized and prepared for the immobilized microorganisms which could effectively remove nitrogen, phosphorus, and mixed organic pollutants in the water sample.
基金Key Project of National Foundation Research from Science and Tech-nology, Ministry of China (2002CCC00900), Key and General Projects of NSFC (No. 60371035) and Project of Society Development of Dalian (2004B3SF181).
文摘With physical method of micro-gap gas discharge, a large amount of hydroxyl radical can be produced in 20t/h pilot-scale system using the ionization of 02 and H2O. In this paper, the effect of biochemistry of hydroxyl radicals on introduced organisms in ballast water was experimentally investigated. The results indicate that the contents of chlorophyl-a, chlorophyl-b, chlorophyl-c and carotenoid are decreased by 35%-4% within 8.0s and further to the lowest limit of test 5 minutes. In addition, the main reasons of cell death are the lipid peroxidation, the strong destruction to the monose, amylose, protein, DNA and RNA of cell, and damage in CAT, POD and SOD of antioxidant enzyme system.
文摘Until recently,potassium(K)has not received considerable attention because of the general belief that soils contain ample amounts of this element.In addition,low rates of K fertilizer application in agriculture have led to rapid depletion of K in the rhizosphere soil in many underdeveloped countries.This results in various negative impacts,including preventing optimum utilization of applied nitrogen and phosphorus fertilizers.To compensate for these losses,massive use of K fertilizers in agriculture has been suggested.Potassium fertilizers are manufactured from rock minerals,particularly sylvite(KCl)and carnallite(KCl·MgCl2·6H2O).Unfortunately,to date,there is no cost-effective technology available for converting rock minerals into potassic fertilizers.Potassium-solubilizing microorganisms(KSMs)can release K from soil/minerals into plant-available forms,which could be a sustainable option.The possibility of using KSMs as efficient biofertilizers to improve crop production has been increasingly highlighted by researchers.In this review,the existing forms of K in soils and their availability and dynamic equilibrium are discussed.In addition,different K fertilizers and their advantages and disadvantages for crops are described.Furthermore,the microorganisms usually reported as K solubilizers,the research progress on KSMs,and future insights on the use of these KSMs in agriculture are reviewed.Screening and analyses of the published literature show that organic acid production is the common mechanism of K solubilization by bacteria and fungi.This review may serve as a proposal for the future research avenues identified here.
基金supported by the National Natural Science Foundation of China (No.51678565)the Special Fund of China (No.AWS18J004)+1 种基金the Tianjin Natural Science Foundation (Nos.19JCYBJC_(2)3800, 19JCZDJC_(3)9800)the National Key R&D Program of China (No.2018YFD0800104)。
文摘Glycogen accumulating organisms(GAOs) are closely related to the deterioration of enhanced biological phosphorus removal systems. However, the metabolic mechanisms that drive GAOs remain unclear. Here, the two-thirds supernatant of a reactor were decanted following the anaerobic period to enrich GAOs. Long-term monitoring demonstrated that the system was stable and exhibited typical characteristics of GAOs metabolism. Acetate was completely consumed after 60 min of the anaerobic phase. The level of glycogen decreased from 0.20 to 0.14 g/gSS during the anaerobic phase, whereas the level of glycogen significantly increased to 0.21g/gSS at the end of the aerobic period. Moreover, there was almost no phosphate release and absorption in the complete periods, thus confirming the successful construction of a GAOs enrichment system. Microbial community analysis demonstrated that Ca. Contendobacter was among the core functional genera and showed the highest activity among all of the communities. Furthermore, our study is the first to identify the involvement of the ethyl-malonyl-CoA pathway in the synthesis of polyhydroxyvalerate via croR, ccr, ecm, mcd, mch and mcl genes. The Embden-Meyerhof-Parnas(EMP) pathway was preferentially used via glgP. Furthermore, the glyoxylate cycle was the main source of ATP under anaerobic conditions, whereas the tricarboxylic acid cycle provided ATP under aerobic conditions. aceA and mdh appeared to be major modulators of the glyoxylate pathway for controlling energy flow. Collectively, our findings not only revealed the crucial metabolic mechanisms in a GAOs enrichment system but also provided insights into the potential application of Ca. Contendobacter for wastewater treatment.
基金supported by the Key Project of National Support Plan from Science and Technology Ministry of China （2006BAC11B06） the Key Project of International Cooperation from the Ministry of Science and Technology of China （2005DFA20800）+1 种基金the Support Plan of National New Century Excellent Youth of China （NCET-04-0286, -05-0398） the Project of National Natural Science Foundation of China （No. 60371035）
文摘With the physical method of micro-gap gas discharge, OH. radicals were produced by the ionization of O2 in air and H2O in the gaseous state, in order to explore more effective method totreat the ship＇s ballast water. The surface morphology of Al2O3 dielectric layer was analysed using Atomic Force Microscopy （AFM）, where the size of Al2O3 particles was in the range of 2 μm to 5 μm. At the same time, the biochemical effect of hydroxyl radicals on the introduced organisms and the quality of ship＇s ballast water were studied. The results indicate that the main reasons of cell death are lipid peroxide and damage of the antioxidant enzyme system in Catalase （CAT）, Peroxidase （POD） and Superoxide dismutase （SOD）. In addition, the quality of the ballast water was greatly improved.
基金supported by the National High Technology Research and Development Program (863) of China (No. 2012AA063406)the National Natural Science Foundation of China (No. 51008005)
文摘Temperature is an important physical factor, which strongly influences biomass and metabolic activity. In this study, the effects of temperature on the anoxic metabolism of nitrite （NO2） to nitrous oxide （N2O） by polyphosphate accumulating organisms, and the process of the accumulation of N2O （during nitrite reduction）, which acts as an electron acceptor, were investigated using 91% ：e 4% Candidatus Accumulibacterphosphatis sludge. The results showed that N2O is accumulated when Accumulibacter first utilize nitrite instead of oxygen as the sole electron acceptor during the denitrifying phosphorus removal process. Properties such as nitrite reduction rate, phosphorus uptake rate, N2O reduction rate, and polyhydroxyalkanoate degradation rate were all influenced by temperature variation （over the range from 10 to 30℃ reaching maximum values at 25℃）. The reduction rate of N2O by N2O reductase was more sensitive to temperature when N2O was utilized as the sole electron acceptor instead of NO2, and the N2O reduction rates, ranging from 0.48 to 3.53 N2O-N/（hr.g VSS）, increased to 1.45 to 8.60 mg N2O-N/（hr·g VSS）. The kinetics processes for temperature variation of 10 to 30℃ were （01 = 1.140-1.216 and θ2 = 1.139-1.167）. In the range of 10℃ to 30℃, almost all of the anoxic stoichiometry was sensitive to temperature changes. In addition, a rise in N2O reduction activity leading to a decrease in N2O accumulation in long term operations at the optimal temperature （27℃ calculated by the Arrhenius model）.
基金Supported by a grant from Sanko Company for EM Production and its produetsa grant from JICA Agency.OIC.Okmawa.Japan
文摘Sludge dewatering and treatment may cost as much as the wastewater treatment.Usually large proportion of the pollutants in wastewater is organic.They are attacked by saprophytic microorganisms,i.e.organisms that feed upon dead organic matter.Activity of organisms causes decomposition of organic matter and destroys them,where the bacteria convert the organic matter or other constituents in the wastewater to new cells,water,gases and other products.Demolition activities,including renovation/remodeling works and complete or selective removal/demolishing of existing structures either by man-made processes or by natural disasters,create an extensive amount of wastes.These demolition wastes are characterized as heterogeneous mixtures of building materials that are usually contaminated with chemicals and dirt.In developing countries, it is estimated that demolition wastes comprise 20%to 30%of the total annual solid wastes.In Egypt,the daily quantity of construction and demolition(C&D) waste has been estimated as 10 000 tones.That is equivalent to one third of the total daily municipal solid wastes generated per day in Egypt.The zabbaliin have since expanded their activities and now take the waste they collect back to their garbage villages where it is sorted into recyclable components:paper,plastics, rags,glass,metal and food.The food waste is fed to pigs and the other items are sold to recycling centers.This paper summarizes the wastewater and solid wastes management in Egypt now and future.
基金a part of the project (20140342) titled " Development of techniques for assessment and management of hazardous chemicals in the marine environment " funded by the Ministry of Oceans and Fisheries, Korea to Jae-Seong Leesupported by the " Korea Polar Ocean Development: K-POD " grant (project no. PM14030) funded by the Ministry of Oceans and Fisheries, Korea
文摘In environmental risk assessments（ERA）, biomarkers have been widely used as an early warning signal of environmental contamination. However, biomarker responses have limitation due to its low relevance to adverse outcomes（e.g., fluctuations in community structure, decreases in population size, and other similar ecobiologically relevant indicators of community structure and function）. To mitigate these limitations, the concept of adverse outcome pathways（AOPs） was developed. An AOP is an analytical, sequentially progressive pathway that links a molecular initiating event（MIE） to an adverse outcome. Recently, AOPs have been recognized as a potential informational tool by which the implications of molecular biomarkers in ERA can be better understood. To demonstrate the utility of AOPs in biomarker-based ERA, here we discuss a series of three different biological repercussions caused by exposure to benzo（a）pyrene（Ba P）, silver nanoparticles（Ag NPs）, and selenium（Se）. Using mainly aquatic invertebrates and selected vertebrates as model species, we focus on the development of the AOP concept. Aquatic organisms are suitable bioindicator species whose entire lifespans can be observed over a short period; moreover, these species can be studied on the molecular and population levels.Also, interspecific differences between aquatic organisms are important to consider in an AOP framework, since these differences are an integral part of the natural environment.The development of an environmental pollutant-mediated AOP may enable a better understanding of the effects of environmental pollutants in different scenarios in the diverse community of an ecosystem.
基金supported in part by the grants from the National Basic Research Program of China (Nos.MOST945300 and MOST944500 to TPZ)the National Natural Science Foundation of China (No.31172173 to TPZ)
文摘Comprehending the diversity of the regenerative potential across metazoan phylogeny represents a fundamental challenge in biology. Invertebrates like Hydra and planarians exhibit amazing feats of regeneration, in which an entire organism can be restored t^om minute body segments. Vertebrates like teleost fish and amphibians can also regrow large sections of the body. While this regenerative capacity is greatly attenuated in mammals, there are portions of major organs that remain regenerative. Regardless of the extent, there are common basic strategies to regeneration, including activation of adult stem cells and proliferation of differentiated cells. Here, we discuss the cellular features and molecular mechanisms that are involved in regeneration in different model organisms, including 14ydra, planarians, zebrafish and newts as well as in several mammalian organs.
文摘The paper elaborates the features and superiority of applying multimedia technology to aquatic organisms in a Science and Life Technology course. The augmented reality application of multimedia technology in aquatic organisms’ instruction has its own features, teaching information capacity, interactive user interface. The paper concludes the superiority of Unity and Vuforia AR instruction from five perspectives;meanwhile, the paper elaborates its disadvantages. An AR-based instruction attitude questionnaire was conducted at the end of the experiment to obtain learners’ perspectives of the system. Learners in AR approach demonstrate higher motivation and concentrate their attention on the learning tasks. Learners showed more positive attitude in willingness to use the AR-based instruction to improve learning interests. This study provided insights for better understanding the design, theory and practice of e-learning through augmented reality technology.
