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Spatio-temporal variability in microfossil and geochemical records of cenomanian-Turonian oceanic anoxic event-2: a review

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Journal of palaeogeography 2024年第4期13卷 646-674页

作者： c.p.Sooraj Shweta Gupta Jahnavi punekar Department of Earth Sciences Indian Institute of Technology Bombay

The cenomanian-Turonian boundary oceanic anoxic event(OAE-2; Bonarelli event; ～94 Ma) is associated with a species turnover in the marine calcareous microfossil record, widespread marine anoxia,black shale deposition and positive δ13c excursions. This study reviews 141 cTBE sites globally, aiming to understand micropaleontological, geochemical, and sedimentological expressions of OAE-2. There is a clear palaeogeographic and palaeobathymetric heterogeneity in the development of OAE-2 marine anoxia. A majority of the documented OAE-2 sites are from deep marine environments. The calcareous nannoplankton and benthic foraminifera record a diversity decline, while planktic foraminifera shows community level shifts and no major mass extinction. The variability of total organic carbon in OAE-2 sediments across sites(10 wt.%) and the δ13c profiles(diachronous) have been attributed to different mechanisms of anoxia *** increased primary “productivity model” gains support from productivity proxies(e.g., Ba, p, cu, Ni),redox-sensitive elements(e.g., Mn, Mo, U, V, As), and eutrophic genera(e.g., benthic foraminifera Gabonita spp., calcareous nannofossils Biscutum spp. and Zeugrhabdotus erectus). The enhanced organic carbon“preservation model” in stratified(semi) restricted basins gains support from sites with lower enrichment of redox-sensitive elements and oligotrophic flora and fauna in the OAE-2 records. Geochronology of the caribbean and the High Atlantic Large Igneous province events(cLIp and HALIp) mark them as likely triggers of the OAE-2 related global perturbation of marine biogeochemistry. Volcanic triggers may have caused climate warming, altered hydrological cycles, enhanced continental weathering, shifts in ocean circulation, and nutrient flows. Addressing knowledge gaps, further research is urged, utilizing innovative proxies, and exploring underrepresented depositional systems to comprehensively understand OAE-2 onset and biotic crisis.

关键词： Oceanic anoxic Event-2 Global organic carbon distribution Geochemical proxies Marine calcifiers palaeoceanography

convergent plate boundary environments for formation of≥3800 Ma mafic-ultramafic assemblages(Isua area,Greenland):Implications for early global geodynamics

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Geoscience Frontiers 2024年第3期15卷 119-136页

作者： Allen p.Nutman clark R.L.Friend Vickie c.Bennett School of Earth Atmospheric and Life SciencesUniversity of WollongongWollongongNSW 2522Australia Glendale TiddingtonOxon OX92LQUK Research School of Earth Sciences Australian National UniversityCanberraACT 2601Australia

In the gneiss terrane on the south side of the Eoarchean Isua supracrustal belt,ultramafic rocks with relict abyssal peridotite mineralogy(Bennett et al.,2002;Friend et al.,2002;Nutman et al.,2007;Rollinson,2007;van de Löcht et al.,2020),layered gabbros with cumulate ultramafic rocks,basalts and associated siliceous sedimentary rocks were tectonically-imbricated,prior to and during intrusion of ca.3800 Ma *** with3800 Ma basalts in the Outer Arc Group of the nearby Isua supracrustal belt,the composition of all these mafic rocks(e.g.,Th-Hf-Nb systematics,high Th/Yb,Ba/Nb,Ba/Yb ratios and negative Nb and Ti anomalies)shows affinity with modern suprasubduction rocks whose genesis involved fluid fluxing of the upper ***,the majority of these samples have Ba/Nb and Ba/Yb values less than in modern island arc magmas,but similar to many backarc basin magmas(e.g.,p.a.c. and Stern,2006).It is unknown whether these ca.3800 Ma mafic rocks are,(i)arc rocks where the Ba/Nb and Ba/Yb signatures reflect lower surficial Ba in Eoarchean oceanic settings,or(ii)in direct comparison with phanerozoic suites,these signatures reflect a back-arc setting with interplay between fluid fluxing and decompressional *** tectonic intercalation of upper mantle with lower and upper crustal rocks,combined with the fluid-fluxing influences seen in chemistry of all the mafic rocks is best accommodated in a compressional Eoarchean convergent plate boundary setting within a mobile-lid *** stagnant lid scenarios of crust formation,if operative,must have co-existed or alternated with mobile-lid regimes by 3800 Ma.

关键词： Eoarchean Fluid-fluxing plate tectonics Suprasubduction crustal evolution

consumer transparency in the production chain for plant varieties produced using new genomic techniques

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aBIOTEcH 2024年第2期5卷 239-246页

作者： J.M.Lukasiewicz c.c.M.van de Wiel L.A.p.Lotz M.J.M.Smulders Wageningen University&Research P.O.Box 386NL-6700 AJ WageningenThe Netherlands

plants edited with new genomic techniques(NGTs)currently fall under the Genetically Modified Organisms Directive(2001/18/Ec)in the European *** the proposal of the European commission,NGT plants are partially exempted from the regulations of this *** proposal makes a distinction between two categories of NGT plants:NGT-1 and ***-1 category plants are considered equal to plants obtained through conventional breeding *** plants will not be labelled for the consumer,although they will be labelled as ***-2 category plants may be labelled with additional information as a positive *** of seeds of varieties made with gene editing,but not the products,would mean that most steps in the production chain are transparent,but not the last step towards ***“right to know”and increasing knowledge of gene-edited food is a common theme in food labelling towards ***,we describe current labelling regimes and registers and how these may be applied to provide transparency on gene-edited products to ***,we also look into consumer studies,which indicate a greater accep.a.c. of gene-edited food among consumers,especially when additional benefits such as sustainability are mentioned.

关键词： Labelling New genomic techniques consumer transparency plant products

Efficient guiding and focusing of intense laser pulse using periodic thin slits

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Matter and Radiation at Extremes 2024年第4期9卷 29-39页

作者： L.Xu T.W.Huang K.Jiang c.N.Wu H.peng p.c.hen R.Li H.B.Zhuo c.T.Zhou Shenzhen Key Laboratory of Ultraintense Laser and Advanced Material Technology Center for Intense Laser ApplicationTechnologyand College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118People’s Republic of China

Slits have been widely used in laser-plasma interactions as plasma optical components for generating high-harmonic light and controlling laser-driven particle ***,we propose and demonstrate that periodic thin slits can be regarded as a new breed of optical elements for efficient focusing and guiding of intense laser *** fundamental physics of intense laser interaction with thin slits is studied,and it is revealed that relativistic effects can lead to enhanced laser focusing far beyond the pure diffractive focusing *** addition,the interaction of an intense laser pulse with periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energy transfer efficiency compared with conventional *** results provide a novel method for manipulating ultra-intense laser pulses and should be of interest for many laser-based applications.

关键词： laser pulse intense

Exposure of juvenile chinook salmon to effluent from a large urban wastewater treatment *** *** profiling

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Aquaculture and Fisheries 2024年第3期9卷 367-377页

作者： James p.Meador Suzanne c.Ball c.Andrew James Jenifer K.McIntyre Dept.of Environmental and Occupational Health Sciences School of Public Health4225 Roosevelt Way NESuite 100SeattleWA98105-6099USA Washington State University School of the EnvironmentPuyallup Research and Extension Center2606 W Pioneer AvePuyallupWA98371USA University of Washington Tacoma Center for Urban Waters326 East D StreetTacomaWA98421-1801USA

Targeted metabolomic analysis was conducted on juvenile chinook salmon exposed for 10 days to wastewater effluent(WWE)from a large urban treatment *** included five dilutions of WWE(20%,5.3%,1.4%,0.4%,and 0.1%)and a control with 7 replicates per *** was extracted from fish and analyzed via liquid chromatography–mass spectrometry(Lc-MS)for 361 endogenous metabolites,of which 185 were ***-versus-treatment comparisons identified several metabolites that were associated with altered biochemical pathways observed for all treatments,including several that are important for energy generation and *** altered pathways are crucial for fish health and may be an early indicator of potential adverse effects on growth,reproduction,behavior,and immune *** ocean-type chinook salmon spend several days to weeks in the nearshore estuary where they may encounter high concentrations of WWE *** are exposed to a wide range of potent pharmaceuticals,personal care products,and industrial compounds from WWE that have the potential to affect physiological homeostasis and disrupt their normal life cycle.

关键词： Wastewater effluent Metabolomics physiology chinook salmon pharmaceuticals Metabolic pathways Estuary

Exposure of juvenile chinook salmon to effluent from a large urban wastewater treatment *** *** responses

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Aquaculture and Fisheries 2024年第3期9卷 355-366页

作者： Suzanne c.Ball James p.Meador c.Andrew James Jenifer K.McIntyre Washington State University School of the EnvironmentPuyallup Research and Extension Center2606 W Pioneer AvePuyallupWA98371USA Dept.of Environmental and Occupational Health Sciences School of Public Health4225 Roosevelt Way NESuite 100SeattleWA98105-6099USA University of Washington Tacoma Center for Urban Waters326 East D StreetTacomaWA98421-1801USA

Wastewater treatment plants release complex mixtures of chemicals into the aquatic environment as wastewater effluent(WWE);however,the effects of these mixtures are still poorly *** salmon(Oncorhynchus tshawytscha)are a culturally important species in the pacific Northwest and are a vital food resource for southern resident killer whales(Orcinus orca)that are listed as‘critically endangered’under the *** Species Act(ESA).chinook populations have declined drastically in this region and have failed to show significant recovery despite regional-to-federal efforts,resulting in many populations being listed as threatened under the *** source of stress to juvenile chinook is chemical pollution from WWE during their outmigration along river corridors and residency in *** this study,we investigated effects of WWE on juvenile chinook health in a ten-day exposure to dilutions of WWE from 0.1%to 20%.At the end of the exposure,we measured endpoints associated with endocrine disruption,brain function,osmoregulation,stress,and *** to WWE significantly(α=0.1 for all analyses)induced vitellogenesis,indicating endocrine system *** saw significant reductions in plasma glucose,an indication of stress,and brain Na+/K+-ATpase(NKA)activity,an enzyme essential for neuronal ***,metabolism was affected as evidenced by altered total protein,cholesterol,and albumin in plasma,a drastic decrease in whole body lipid content,and a significant increase in visible liver *** compared contaminant concentrations in exposure water with effects concentrations from the literature for chemicals known to induce vitellogenin or inhibit brain *** most contaminants,concentrations in exposure waters were several orders of magnitude below effects concentrations in the *** exception was estrogenic hormones,which were detected at similar concentrations in this study compared to concentrations in other studies tha

关键词： Wastewater effluent chinook salmon Toxicity Sodium potassium ATpase Vitellogenin physiology Metabolism Glucose

Seasonal changes in Hermit Thrush (catharus guttatus) song syntax

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Avian Research 2024年第2期15卷 172-179页

作者： Sean p.Roach Luke c.McLean Jeff W.MacLeod Leslie S.phillmore psychology Department University of New Brunswick Saint John100 Tucker Park RoadSaint JohnNBCanada Department of psychology and Neuroscience Dalhousie University1355 Oxford StHalifaxNSB3H 4J1Canada

In many songbird species,birdsong features phonological syntax,meaning that the units within their vocal se-quences are ordered in a non-random way that adheres to a *** such syntactical patterns have been richly described in many species,comparatively little is known about how those patterns contribute to song achieving its important *** each of song’s main functions,territorial defense and mate attraction,evidence of a role for syntax is *** species for which syntax has been thoroughly described is the Hermit Thrush(catharus guttatus),which presents song types from their repertoires in a semi-predictable order and,in doing so,rapidly cycle up and down the frequency *** objective of the present study was to explore the importance of song syntax in the Hermit Thrush through a within-subject examination of how measures of syntax,such as the predictability of song type order within song sequences,shift over the breeding *** hypothesized that,if such syntactical characteristics are important to breeding behaviour,they would be most prominent at the start of the breeding season when activity associated with territory establishment and mate attraction is most *** revealed that,as predicted,the rigidness of song type ordering within se-quences was highest at the start of the season and declined *** song type sequences were most predictable at the vitally important early part of the breeding season fit our hypothesis that this aspect of song syntax is important to song’s functions related to territory establishment and/or mate *** work will clarify whether that role relates to one of song’s two main functions or serves song transmission in some broader way.

关键词： Birdsong Hermit Thrush Seasonal change Stereotypy Syntax

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Exploring one material for dual applications:A red-emitting Mg2GeO4:Eu3+ nanophosphor for future generation energy efficient WLEDs and dosimetric applications

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Journal of Rare Earths 2024年第10期42卷 1835-1845页

作者： Akshay Arjun G.p.Darshan S.c.Sharma H.Nagabhushana D.V.Sunitha H.B.premkumar Department of physics Faculty of Mathematical and Physical SciencesM.S.Ramaiah University of Applied Sciences Jain University c.N.R.Rao centre for Advanced Materials Tumkur University School of Applied Sciences (physics) REVA University

The envisaged design and developme nt of individual mate rials to excavate a broader spectrum of desired properties and offer multiple applications are highly *** this in mind,a series of forsterite-structured Mg2GeO4:Eu3+（1 mol%-9 mol%） nanophosphors was synthesized via a solution combustion method using oxalyl dihydrazide as a *** X-ray diffraction patterns confirm the orthorhombic crystal system with a puma space *** results clearly show irregularly shaped cluster-like structures with aggregation of the *** diffuse reflectance spectra,the optical energy band gap of the Mg2GeO4:Eu3+（1 mol%-9 mol%） nanophosphors was estimated and obtained to be～4.12-4.32 *** photoluminescence emission spectra exhibit intense peaks at ～579,589,610,661,and 707 nm,which are due to characteristic5D0→7F0,5D0→7F1,5Do→7F2,5D0→7F3and5D0→7F4transitions of Eu3+ions,*** commission International de L'Eclairage color coordinates are gradually tuned from pale red（0.5980,0.4012） to a pure red（0.6385,0.3611） *** glow peaks showcase excellent super-linear response at low doses of γ-irradiations,indicating that the prepared phosphor can be used in thermoluminescent personal dosimetry which is a biological tissue *** aforementioned results demonstrate that the prepared Mg2GeO4:Eu3+（1 mol%-9 mol%） nanophosphors are considered an excellent candidate for dual applications,i.e.,red component in future generation white-light-emitting diodes（WLEDs） and personal dosimetric applications.

关键词： Dosimetry Nanophosphors photoluminescence photometric properties Rare earths Thermoluminescence

实验室培养肉进入顾客餐桌——机遇与挑战并存

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Engineering 2024年第3期34卷 3-5页

作者： Sarah c.p.Williams Senior Technology Writer

In the summer of 2023,two US restaurants added a novel item to their menus:chicken grown in a lab(Fig.1)[1,2].The first to receive regulatory approval for commercial sale,the lab-grown—or"cultivated"—meat starts as a few real chicken cells that are grown in vats of liquid and nutrients until they become pieces large enough to shape into nuggets and strips.

关键词：实验室培养 approval restaurant

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