检索结果-南通市图书馆

Gastric carboxylesterases of the edible crab Cancer pagurus (Crustacea, Decapoda) can hydrolyze biodegradable plastics

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Emerging Contaminants 2024年第1期10卷 80-89页

作者： Lukas Miksch Lars Gutow Reinhard Saborowski Alfred Wegener Institute Helmholtz Centre for Polar and Marine ResearchAm Handelshafen 1227570BremerhavenGermany

A promising strategy to counteract the progressing plastic pollution of the environment can involve the replacement of persistent plastics with biodegradable *** polymers are enzymatically degradable by various hydrolytic ***,these materials can reach the environment in the same way as conventional ***,they are accessible to terrestrial,freshwater,and marine *** ingested by marine organisms,highly active enzymes in their digestive tracts may break down biodegradable *** incubated microparticles of five different biodegradable plastics,based on polylactictic acid(PLA),polybutylene succinate(PBS),polybutylene adipate terephthalate(PBAT)and polyhydroxybutyrate-co-valerate(PHBV),in-vitro with the gastric fluid of the edible crab Cancer pagurus and evaluated the hydrolysis rates by pH Stat titration.A plastic blend of PLA with PBAT showed the highest hydrolysis *** enzymes in the gastric fluid of crabs were separated by anion exchange *** with carboxylesterase activity were identified using fluorescent methylumbelliferyl(MUF)-*** fractions with high carboxylesterase activity also hydrolyzed a PLA/PBAT plastic *** showed molecular masses of 40–45 kDa as determined by native gel electrophoresis(SDS-PAGE).Our study demonstrated that digestive carboxylesterases in the gastric fluid of *** exhibit a high potential for hydrolyzing certain biodegradable *** esterases are common in the digestive tract of organisms,it seems likely that other invertebrates possess the ability to hydrolyze biodegradable plastics.

关键词： Biodegradable plastics Microplastics Crustaceans Ingestion Enzymes Enzymatic degradation

Photosynthetic response to a winter heatwave in leading and trailing edge populations of the intertidal red alga Corallina offi-cinalis(Rhodophyta)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2024年第7期43卷 70-77页

作者： Regina Kolzenburg Federica Ragazzola Laura Tamburello Katy R.Nicastro Christopher D.McQuaid Gerardo I.Zardi Umeåmarine Sciences centre UmeåUniversity90571 NorrbynSweden University of Portsmouth Institute of Marine SciencePortsmouth PO49LYUK Stazione Zoologica Anton Dohrn Genova Marine CenterGenova 16126Italy Stazione Zoologica Anton Dohrn Sicily Marine CenterPalermo 90149Italy Department of Zoology and Entomology Rhodes UniversityMakhanda(Grahamstown)6139South Africa centre of marine Sciences University of AlgarveFaro 8005-139Portugal Laboratoire d’Océanologie et de Géosciences Universitéde LilleLille 59000France Universitéde Caen Normandie Laboratoire de Biologie des Organismes et des Ecosystèmes AquatiquesCaen 14032France

marine heatwaves(MHWs)caused by anthropogenic climate change are becoming a key driver of change at the ecosystem *** conditions experienced by marine organisms across their distribution,particularly towards the equator,are likely to approach their physiological limits,resulting in extensive mortality and subsequent changes at the population *** at the margins of their species’distribution are thought to be more sensitive to climate-induced environmental pressures than central populations,but our understanding of variability in fitness-related physiological traits in trailing versus leading-edge populations is *** a laboratory simulation study,we tested whether two leading(Iceland)and two trailing(Spain)peripheral populations of the intertidal macroalga Corallina officinalis display different levels of maximum potential quantum efficiency(Fv/Fm)resilience to current and future winter MHWs *** study revealed that ongoing and future local winter MHWs will not negatively affect leading-edge populations of ***,which exhibited stable photosynthetic efficiency throughout the *** edge populations showed a positive though non-significant trend in photosynthetic efficiency throughout winter MHWs *** and equatorward populations did not produce significantly different results,with winter MHWs having no negative affect on Fv/Fm of either ***,we found no long-term regional or population-level influence of a winter MHWs on this species’photosynthetic ***,we found no statistically significant difference in thermal stress responses between leading and trailing ***,*** showed a trend towards higher stress responses in southern than northern *** responses rest on a variety of local population traits,they are difficult to predict based solely on thermal pressures.

关键词： marginal population coralline algae climate change ecophysiology photophysiology macroalgae Fv/Fm

Experimental and numerical investigation of the impacts of rotor tip-rake on excitation forces of pump-jet propulsors

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2024年第1期36卷 142-157页

作者： Xue-qin Ji Xiao-song Zhang Chen-jun Yang Xiao-qian Dong State Key Laboratory of Ocean Engineering Marine Numerical Experiment CentreSchool of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China CSSC Shanghai marine Energy Saving Technology Co. Ltd.Shanghai200011China China Ship Scientific Research Center Shanghai Branch Shanghai200011China

The tip-clearance flow in a pump-jet propulsor exerts great impacts on the fluctuating pressures and resultant unsteady forces,which are important sources of structural vibrations and radiated noise *** blade geometry close to the tip is an important factor determining the vortex strength in the tip-clearance *** the open-water condition,the effects of raking the rotor tips on the duct-surface fluctuating pressures and the resultant unsteady forces acting on different components of the propulsor are investigated via physical model experiments and the numerical solution of Reynolds-averaged Navier-Stokes(RANS)equations coupled with the SST k-ωturbulence *** measured and simulated results of hydrodynamic pressures are consistent to each other,and the simulated flows help better understand why the fluctuating pressures change with the tip *** strong fluctuations of duct-surface pressures are caused by intensive tip separation *** duct-surface pressure fluctuations are effectively reduced by using the rake distribution near the tip towards blade back side and,for the combination of the five-bladed rotor and the seven-bladed stator,the resultant unsteady horizontal(and vertical)forces acting on the duct and stator are also reduced;while increasing rake leads to negative effect on pressure fluctuations and unsteady horizontal(and vertical)forces acting on all the components of the propulsor.

关键词： Pump-jet tip-clearance tip-rake fluctuating pressures excitation forces

Vallisneria spiralis L. adaptive capacity improves pore water chemistry and increasespotential nitrification in organic polluted sediments

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Ecological Processes 2024年第2期 72-89页

作者： Leonardo Morini Claudio Ferrari Marco Bartoli Mindaugas Zilius Elias Broman Giovanna Visioli Department of Chemistry Life Science and Environmental Sustainability University of Parma Department of Environmental and Prevention Sciences University of Ferrara Department of Integrative marine Ecology (EMI) Genoa Marine Centre Stazione Zoologica Anton Dohrn-National Institute of Marine BiologyEcology and Biotechnology marine Research Institute Klaipeda University Department of Ecology Environment and Plant Sciences Stockholm University Baltic Sea centre Stockholm University

Background Macrophytes may modify benthic biodiversity and biogeochemistry via radial oxygen loss from roots. This condition contrasts sediments anoxia, allows roots respiration, and facilitates aerobic microbial communities and processes in the rhizosphere. Simultaneously, the rhizosphere can stimulate anaerobic microorganisms and processes via exudates or by favoring the build-up of electron acceptors as nitrate. As eutrophication often results in organic enrichment in sediments and large internal nutrients recycling, an interesting research question is to investigate whether plants maintain the capacity to stimulate aerobic or anaerobic microbial communities and processes also under elevated organic *** A manipulative experiment was carried out under laboratory-controlled conditions. Microcosms containing bare sediments and sediments transplanted with the macrophyte Vallisneria spiralis L. were created. The effect of the plant was investigated on sediments with moderate(8%) and elevated(21%) organic matter content, after an acclimatization period of 30 days. Chemical and physical parameters, microbial community composition and the potential rates of nitrification, denitrification and nitrate ammonification were measured at two different depths(0–1 and 1–5 cm) after the acclimatization period to evaluate the role of *** Vallisneria spiralis grew and assimilated pore water nutrients at the two organic matter levels and vegetated sediments had always nutrient-depleted porewaters as compared to bare sediments. Nitrifying microbes had a lower relative abundance and diversity compared to denitrifying bacteria. However, regardless of the organic content, in vegetated sediments nitrifiers were detected in deeper horizons as compared to bare sediments, where nitrification was confined near the surface. In contrast, potential denitrification rates were not affected by the presence of roots, but probably regulated by the presence of nitrate and by ro

关键词：

A CFD study on the hydrodynamic response of a small-scale ice floe induced by a passing ship

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2024年第2期36卷 290-299页

作者： Zongyu Jiang Spyros Hirdaris Sasan Tavakoli Mikko Suominen Pentti Kujala marine and Arctic Technology Department of Mechanical EngineeringAalto UniversityEspooFinland Global Ship Systems centre ABS Hellenic SM LLC.AthensGreece Department of Infrastructure Engineering The University of MelbourneMelbourneAustralia

A Reynolds averaged Navier-Stokes(RANS)computational fluid dynamics(CFD)model is built to investigate the hydrodynamic response of a circular ice floe under the influence of a passing ship in calm *** ship,mirroring the KRISO Container Ship’s hull design,progresses near an ice floe whose diameter is 30%of the ship’s length and its thickness is 3 *** ship advances at a constant speed,which is handled by using the overset mesh *** study focuses on the ice floe’s motions and the hydrodynamic forces induced by three speeds and three transverse distances of the passing *** reveal that ship-generated wakes notably influence the ice floe’s motions,with a greater influence on sway than ***,the ship’s speed and proximity distinctly affect the ice floe’s motions.

关键词： Hydrodynamics ship-ice interactions ice floe Reynolds averaged Navier-Stokes(RANS)computational fluid dynamics(CFD)

A review on the parasitic isopod genus Notophryxus ***,1883(Crustacea:Isopoda),and first report of Notophryxus globularis ***,1885 from Lakshadweep Sea(Amini Island)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2024年第8期43卷 142-153页

作者： Mukkattu Nazar Suhaana Jaime Gómez-Gutiérrez Paravanparambil Rajakumar Jayachandran Punnakkal Hari Praved Sivasankaran Bijoy Nandan Department of marine Biology Microbiology and BiochemistrySchool of Marine SciencesCochin University of Science and TechnologyKochi-Kerala 682016India Departamento de Plancton y Ecología Marina Centro Interdisciplinario de Ciencias MarinasInstituto Politécnico NacionalLa Paz B.C.S.23096Mexico Applied Research centre for Environment and marine Studies King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia

Isopod crustaceans of the family Dajidae are exclusively marine *** genus Notophryxus ***,1883 currently includes nine nominal species,which are very rarely reported as the chances for encountering these specimens are *** comprehension of the taxonomy,biology,ecology,and life cycle of species belonging to the Notophryxus genus is notably *** nominal species of Notophryxus genus are reviewed here to obtain a comprehensive and integrative taxonomic understanding of this genus,in an attempt to address the *** paper also documents the rediscovery of an ectoparasitic isopod from the genus Notophryxus in Indian waters,after 55 *** isopod specimens obtained from the outer reefs of Amini Island in the Lakshadweep archipelago,Southeastern Arabian Sea,display morphological congruence to Notophryxus globularis ***,*** only previous report on this species dates back to 1885 from ***'description of *** as an ectoparasite on the euphausiid Thysanoessa gregaria ***,1883 in the North *** discovery represents a range extension of *** from the North Pacific to the Arabian *** cryptoniscid larvae and three adult females of ***(with dwarf males)were found attached to four adult mysid specimens of Siriella aequiremis Hansen,*** present study provides an improved diagnosis of *** with the aid of light microscopy images and line drawings which was not given in the original ***,1885 *** research also provides a concise description of cryptoniscid larvae from the same sampling location and same host which is most likely to be *** larvae.

关键词： Dajiidae Mysid cryptoniscan larvae Southeastern Arabian Sea Notophryxus

Insights into carbon dioxide sequestration into coal seams through coupled gas flow-adsorption-deformation modelling

在线全文

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 26-40页

作者： Hywel Thomas Min Chen Geoenvironmental Research centre Cardiff School of EngineeringCardiff UniversityQueen’s BuildingsThe ParadeNewport RoadCardiffCF243AAUK Key Laboratory of marine Geology Tongji UniversityShanghai200092China

Injecting carbon dioxide(CO_(2))into coal seams may unlock substantial carbon sequestration *** the coal acts like a carbon filter,it can preferentially absorb significant amounts of CO_(2).To explore this further,desorption of the adsorbed gas due to pressure drop is investigated in this paper,to achieve an improved understanding of the long-term fate of injected CO_(2) during post-injection *** paper presents a dual porosity model coupling gas flow,adsorption and geomechanics for studying coupled processes and effectiveness of CO_(2) sequestration in coals.A new adsorption?desorption model derived based on thermodynamics is incorporated,particularly,the desorption hysteresis is *** reliability of the proposed adsorption-desorption isotherm is examined via validation *** is indicated that occurrence of desorption hysteresis is attributed to the adsorption-induced pore *** injection ceases,the injected gas continues to propagate further from the injection well,while the pressure in the vicinity of the injection well experiences a significant *** the adsorbed gas near the well also decreases,this decrease is less compared to that in pressure because of desorption *** unceasing spread of CO_(2) and drops of pressure and adsorbed gas depend on the degree of desorption hysteresis and heterogeneity of coals,which should be considered when designing CO_(2) sequestration into coal seams.

关键词： CO_(2)geological storage Coal seam Adsorption Desorption hysteresis

Recent Advances of Bioactive marine Natural Products in Drug Discovery

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Ocean University of China 2024年第5期23卷 1297-1318页

作者： ZHANG Qun LV Liuxia WANG Wenhui WEI Meiyan GU Yucheng SHAO Changlun Key Laboratory of marine Drugs Ministry of Education of ChinaSchool of Medicine and PharmacyOcean University of ChinaQingdao 266100China Laboratory for marine Drugs and Bioproducts Qingdao Marine Science and Technology CenterQingdao 266237China Key Laboratory of Tropical Medicinal Resource Chemistry of Ministry of Education College of Chemistry and Chemical EngineeringHainan Normal UniversityHaikou 571158China Syngenta Jealott’s Hill International Research centre BracknellBerkshire RG426EYUK

marine natural products(MNPs)are valuable resources for drug *** date,17 drugs from marine sources are in clinical use,and 33 pharmaceutical compounds are in clinical *** the success of drug development from the marine resources is higher than the industry *** is a feasible strategy to conduct the discovery of druglead compounds based on marine chemical ecology by fully exploiting the pharmacological potential of marine chemical defense *** the search for bioactive MNPs,our group has constructed a biological resources library including more than 1500 strains of *** on the strategy of Blue Drug Library,we have discovered a series of novel MNPs with abundant biological *** efficient and scalable total synthesis of(+)-aniduquinolone A(44)and pesimquinolone I(48)have been completed,which will facilitate access to sufficient quantities of candidates for in vivo pharmacological and toxicological *** a nucleoprotein(NP)inhibitor,QLA(75)possesses significant anti-influenza A virus(IAV)activities both in vitro and in ***-00803(76)is a potent and selective AMP-activated kinase(AMPK)activator that can effectively inhibit metabolic disorders and metabolic dysfunction-associated steatohepatitis(MASH)***,we identified two new candidate molecules with potent anti-hepatocellular carcinoma ***,as a natural guanine-nucleotide exchange factors for ADP-ribosylation factor GTPases(Arf-GEFs)inhibitor prodrug,CHNQD-01255(78)is qualified to be developed as a targeted candidate anticancer drug,which may be promising to apply for cancer ***,it is evident that MNPs play an important role in drug development.

关键词： marine medicinal organisms natural products marine drug discovery and optimization drug development

Physics-embedded machine learning search for Sm-doped PMN-PT piezoelectric ceramics with high performance

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2024年第8期33卷 81-88页

作者：辛睿王亚祺房泽郑凤基高雯付大石史国庆刘建一张永成 College of Physics Center for Marine Observation and CommunicationsNational Demonstration Center for Experimental Applied Physics EducationQingdao UniversityQingdao 266071China centre for Theoretical and Computational Physics College of PhysicsQingdao UniversityQingdao 266071China

Pb(Mg_(1/3)Nb_(2/3))O_(3)–PbTiO_(3)(PMN-PT)piezoelectric ceramics have excellent piezoelectric properties and are used in a wide range of *** the solid solution ratios of PMN/PT and different concentrations of elemental doping are the main methods to modulate their piezoelectric *** combination of these controllable conditions leads to an exponential increase of possible compositions in ceramics,which makes it not easy to extend the sample data by additional experimental or theoretical *** this paper,a physics-embedded machine learning method is proposed to overcome the difficulties in obtaining piezoelectric coefficients and Curie temperatures of Sm-doped PMN-PT ceramics with different *** contrast to all-data-driven model,physics-embedded machine learning is able to learn nonlinear variation rules based on small datasets through potential correlation between ferroelectric *** on the model outputs,the positions of morphotropic phase boundary(MPB)with different Sm doping amounts are *** also find the components with the best piezoelectric property and comprehensive ***,we set up a database according to the obtained results,through which we can quickly find the optimal components of Sm-doped PMN-PT ceramics according to our specific needs.

关键词： Pb(Mg_(1/3)Nb_(2/3))O_(3)–PbTiO_(3)(PMN-PT)ceramic physics-embedded machine learning piezoelectric coefficient Curie temperature