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Small size does not restrain frugivory and seed dispersal across the evolutionary radiation of Galapagos lava lizards

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Current Zoology 2019年第4期65卷 353-361页

作者： sandra HERVIAS-PAREJO Ruben HELENO Beatriz RUmEU Beatriz GUZmAN Pablo VARGAS Jens m. OLESEN Anna TRAVESET Carlos VERA Edgar BENAVIDES manuel NOGALES Institut mediterrani d'Estudis Avanqats (CSIC-UIB) Global Change Research Group Mallorca Balearic Islands Spain Centre for Functional Ecology Department of Life Sciences University of Coimbra Portugal Real Jardin Botanico (CSIC-RJB) Madrid Spain Department of Bioscience Aarhus University Denmark Galapagos National Park Puerto Ayora Santa Cruz Galapagos Ecuador Department of Ecology and Evolutionary Biology Yale University USA lnstituto de Productos Naturales Agrobiologia (CSIC-IPNA) Island Ecology and Evolution Research Group Canary Islands Spain

Frugivory in lizards is often assumed to be constrained by body size;only large individuals are considered capable of consuming fruits, with the potential of acting as seed dispersers. However, only one previous study has tested the correlation of frugivory with body and head size at an archipelago scale across closely related species. All nine lava lizards (microlophus spp.) were studied on the eleven largest Galapagos islands from 2010 to 2016 to investigate whether frugivory is related to body and head size. We also tested whether fruit abunda nee in flue nces fruit con sumption and explored the effect of seed ingestion on seedling emergence time and percentage. Our results showed that across islands, lava lizards varied considerably in size (64-102 mm in mean snoutvent length) and level of frugivory (1-23%, i.e., percentage of droppings with seeds). However, level of frugivory was only weakly affected by size as fruit consumption was also common among small lizards. Lava lizards consumed fruits throughout the year and factors other than fruit abundance may be more importa nt drivers of fruit selecti on (e.g., fruit size, energy con tent of pulp). From 2,530 droppings, 1,714 seeds of at least 61 plant species were identified, 76% of the species being native to the Galapagos. most seeds (91%) showed no external structural damage. Seedling emergence time (44 versus 118 days) and percentage (20% versus 12%) were enhanced for lizardingested seeds compared to control (uningested) fruits. De-pulping by lizards (i.e., removal of pulp with potential germi nation inhibitors) might in crease the chances that at least some seeds find suitable recruitment conditi ons. We con eluded that lizards are importa nt seed dispersers throughout the year and across the whole archipelago, regardless of body size.

关键词： microlophus oceanic islands plant-animal interactions seed disperser size seed dispersal effectiveness seedling emergence

UDP-glucuronosyltransferases mediate coffee-associated reduction of liver fibrosis in bile duct ligated humanized transgenic UGT1A mice

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Hepatobiliary Surgery and Nutrition 2021年第6期10卷 766-781页

作者： Steffen Landerer sandra Kalthoff Christian P.Strassburg Department of Internal medicine I University Hospital BonnVenusberg-Campus 1BonnGermany

Background:Coffee consumption has been shown to reduce the risk of liver fibrosis and is capable of inducing human UDP-glucuronosyltransferase(UGT)1A ***1A enzymes act as indirect antioxidants catalyzing the elimination of reactive metabolites,which in turn are potent initiators of profibrotic *** aim of this study was to analyze the role of UGT1A genes as effectors of the protective properties of coffee in bile duct ligation(BDL)induced liver ***:Fourteen days BDL with and without coffee pre-and co-treatment was performed in htgUGT1A-WT and htgUGT1A-SNP *** UGT1A mRNA expression levels,serum bilirubin and aminotransferase activities were *** fibrosis was assessed by collagen deposition,computational analysis of Sirius red tissue staining and expression of profibrotic marker *** stress was measured by hepatic peroxidase concentrations and immunofluorescence ***:UGT1A transcription was differentially activated in the livers of htgUGT1A-WT mice after BDL,in contrast to a reduced or absent induction in the presence of ***-treated(coffee+BDL)htgUGT1A-WT-mice showed significantly increased UGT1A expression and protein levels and a considerably higher induction compared to water drinking WT mice(BDL),whereas in co-treated htgUGT1A-SNP mice absolute expression levels remained below those observed in htgUGT1A-WT *** deposition,oxidative stress and the expression of profibrotic markers inversely correlated with UGT1A expression levels in htgUGT1A-WT and SNP mice after BDL and coffee+BDL ***:Coffee exerts hepatoprotective and antioxidative effects via activation of UGT1A *** hepatic fibrosis as a result of coffee-mediated UGT1A induction during cholestasis was detected,while the protective action of coffee was lower in a common low-function UGT1A SNP haplotype present in 10%of the Caucasian *** study suggests that coffee consumption might

关键词： Glucuronidation cholestasis liver fibrosis coffee oxidative stress

Development of barium@alginate adsorbents for sulfate removal in lithium refining

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Frontiers of Chemical Science and Engineering 2021年第1期15卷 198-207页

作者： Lisa Xu Kaifei Chen George Q.Chen sandra E.Kentish Gang(Kevin)Li Department of Chemical Engineering The University of MelbourneParkvilleVIC 3010Australia

The demand for lithium has been steadily growing in recent years due to the boom of electric *** purity lithium is commonly used in the manufacture of battery grade lithium *** residuals originating from acid leaching of lithium ores must be limited to below 20 mg·L^(−1) during *** are methods to remove sulfate such as membrane processing and chemical precipitation using barium ***,membrane separation is unable to achieve the required purity while chemical precipitation often causes secondary contamination with barium and requires extra filtration processes that lead to increased processing *** this study,we developed a polymeric matrix entrapped with barium ions as a novel adsorbent to selectively adsorb sulfate in aqueous *** adsorbent was prepared by dropwise injection method where alginate droplets were crosslinked with barium to form hydrogel *** a typical scenario,the microcapsules had a diameter of 3 mm and contained 5 wt-%*** microcapsules could successfully reduce sulfate concentration in a solution from 100 to 16 mg·L^(−1),exceeding the removal ***,the microcapsules were mechanically unstable in the presence of an excess amount of ***,calcium ions were added as a secondary crosslinking agent to improve the integrity of the *** two-step Ca/Ba@alginate microcapsules showed an exceptional adsorption performance,reducing the sulfate concentration to as low as 0.02 mg·L^(−1).Since the sulfate selective microcapsules can be easily removed from the aqueous system and do not result in secondary barium contamination,these Ca/Ba@alginate adsorbents will find applications in ultra-refining of lithium in industry.

关键词： barium@alginate microcapsules dropwise injection sulfate removal lithium

Shaken not stirred: A molecular contribution to the systematics of genus mugil (Teleostei, mugilidae)

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Integrative Zoology 2016年第4期11卷 263-281页

作者： sandra HERAS Ferruccio mALTAGLIATI maria Victoria FERNÁNDEZ maría Inés ROLDÁN Laboratory of Genetic Ichthyology University of GironaGironaSpain Department of Biology University of PisaPisaItaly

With this work we addressed some molecular systematic issues within the mugil cephalus species ***ticular attention was paid to the debated situations of:(i)mugil liza,occurring in partial sympatry with mugil cephalus in the northwestern Atlantic,and(ii)mugil platanus,considered by some authors a synonymy of the former species and distributed in the southwestern *** sequenced 79 individuals of a 465-bp portion of the mitochondrial control region(CR)from 8 western Atlantic and 2 mediterranean *** addition,all CR sequences available from GenBank for the studied taxa were added to our dataset,for a total of 323 indi***,229 haplotypes corresponding to 8 divergent monophyletic lineages were *** of phylogenetic analyses were consistent with the occurrence of past speciation events producing the observed lin*** these lineages,7 correspond to cryptic species and one is constituted by *** and *** a matter of fact,these 2 taxa constitute a single lineage within the *** species ***,individuals of ***/*** lineage analyzed by means of the 18 mitochondrial markers available in GenBank exhibited a degree of genetic diversity consistent with highly divergent *** the 8 lineages detected,the mediterraean one(type locality)corresponds to ***;the lineage ***/*** should be named ***,under the priority principle,and the left 6 lineages need formal description.

关键词： cryptic species historical demography molecular phylogeny mugil systematics

Diversity of dictyostelid social amoebae in high latitude habitats of Northern Sweden

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Fungal Diversity 2013年第1期58卷 185-198页

作者： Allison L.Perrigo sandra L.Baldauf maria Romeralo Program in Systematic Biology Department of Organismal BiologyEvolutionary Biology CenterUppsala UniversityNorbyvägen 18D75236 UppsalaSweden

The dictyostelid social amoebae(Dictyostelia)occur in terrestrial habitats *** has been observed previously that their diversity decreases with increasing latitude and *** we look at dictyostelid diversity in the high latitude habitats of Northern *** were recovered from soil samples using traditional plating methods and then identified using morphological characters and molecular sequence(small subunit ribosomal RNA)*** total,nine species were recovered,including two new species,described herein as Dictyostelium barbibulus and Polysphondylium *** species diversity found here is discussed in relation to previous findings in the area as well as other high-latitude studies,and biogeographical patterns are *** total number of species found in Northern Sweden is lower than the numbers recorded for regions further south in Europe,a finding consistent with a latitudinal gradient of species *** findings highlight the benefit of using molecular data for accurate species identification in Dictyostelia and the need for a continued sampling effort to better understand their diversity and distribution,especially in high latitude habitats.

关键词： Cellular slime mold Dictyostelium molecular identification New species Protist biogeography Sweden

The effects of tannins-containing ground pine bark diet upon nutrient digestion,nitrogen balance,and mineral retention in meat goats

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Journal of Animal Science and Biotechnology 2015年第3期6卷 347-354页

作者： Byeng Ryel min sandra Solaiman Thomas Terrill Aina Ramsay Irene mueller-Harvey Department of Agricultural and Environmental Sciences Tuskegee University Agricultural Research Station Fort-Valley State University School of Agriculture Policy and DevelopmentUniversity of Reading

Background： Pine bark is a rich source of phytochemical compounds including tannins, phenolic acids, anthocyanins, and fatty acids. These phytochemicals have potential to significantly impact on animal health and animal production. The goal of this work is to measure the effects of tannins in ground pine bark as a partial feed replacement on feed intake, dietary apparent digestibility, nitrogen balance, and mineral retention in meat goats. Results： Eighteen Kiko cross goats （initial BW = 31.8 ± 1.49 kg） were randomly assigned to three treatment groups （n = 6）. Dietary treatments were tested： control （0 % pine bark powder （PB） and 30 % wheat straw （WS））; ] 5 % PB and 15 % WS, and 30 % PB and 0 % WS. Although dry matter （Dm） intake and digestibility were not affected （P〉 0.10） by feeding PB, neutral detergent fiber （linear; P= 0.01）, acid detergent fiber （linear; P= 0.001） and lignin digestibility （linear; P= 0.01） decreased, and crude protein （CP） digestibility tended to decrease （P=0.09） as PB increased in the diet, apparent retention of Ca （P= 0.09）, P （P=0.03）, mg （P= 0.01）, mn （P= 0.01）, Zn （P= 0.01） and Fe （P= 0.09） also increased linearly. Nitrogen intake and fecal N excretion were not affected （P〉 0.05） by addition of PB in the diet, but N balance in the body was quadratically increased （P〈 0.01） in the 15 % PB diet compared to other diets. This may be due to more rumen escape protein and less excreted N in the urine with the 15 % PB diet. The study showed that a moderate level of tannin-containing pine bark supplementation could improve gastrointestinal nitrogen balance with the aim of improving animal performance. Conclusion： These results suggest that tannin-containing PB has negative impact on fiber, lignin, and protein digestibility, but positively impacted on N-balance.

关键词： Digestibility Goats Phytochemicals Tannins

Reproductive biology of largehead hairtail(Trichiurus lepturus)in south-eastern Australia

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Aquaculture and Fisheries 2023年第2期8卷 148-158页

作者： Chantelle Clain John Stewart Ashley Fowler sandra Diamond School of Science Western Sydney UniversityLocked Bag 1797PenrithNSW2751Australia NSW Department of Primary Industries Sydney Institute of Marine ScienceChowder Bay RoadMosmanNSW2088Australia

Knowledge of reproductive biology and life-history traits of populations exploited by fisheries is important for their sustainable *** investigated the life-history traits of Trichiurus lepturus(largehead hairtail)in south-eastern Australia;a region of low exploitation for this otherwise heavily exploited circumglobal species,to investigate whether there were differences in the reproductive biology and life-history traits in the south-east Australian population compared with those in other *** also used histological sections to examine male and female gonads at a microscopic *** lepturus in south-eastern Australia had a greater maximum length(193 cm total length(TL)),matured at a larger length(108 cm TL at 50%mature)and had a spawning period(march to September,Austral winter)that was inconsistent with other *** overall sex ratio of 1:0.4 females:males was consistent with a female dominant sex ratio observed in other regions,particularly in larger length ***,females in the current study dominated samples from both estuarine and coastal habitats,as well as during the spawning and non-spawning periods,which is not consistent with the patterns found in other *** in south-eastern Australia may relate to limited fishing pressure,genetic variation,or differences in environmental factors that influence reproductive development,including temperature,trophic resources and habitat.

关键词： Fisheries Length at maturity Histology Spawning period Sex ratio Trichiurus

A geometric interpretation of the transition density of a symmetric Lévy process

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Science China mathematics 2012年第6期55卷 1099-1126页

作者： JACOB Niels KNOPOVA Victorya LANDWEHR sandra SCHILLING RenéL. Department of mathematics Swansea UniversitySingleton ParkSwansea SA28PPUK V.m.Glushkov Institute of Cybernetics NAS of Ukraine 03187KievUkraine Heinrich Heine University Düsseldorf German Diabetes Center at the Heinrich Heine University DüsseldorfLeibniz Center for Diabetes ResearchInstitute of Biometrics and EpidemiologyAuf'm Hennekamp 6540225 DüsseldorfGermany Institut für mathematische Stochastik Technische Universität Dresden01062 DresdenGermany

We study for a class of symmetric Levy processes with state space R^n the transition density pt（x） in terms of two one-parameter families of metrics, （dt）t〉o and （δt）t〉o. The first family of metrics describes the diagonal term pt （0）; it is induced by the characteristic exponent ψ of the Levy process by dr（x, y） = √tψ（x - y）. The second and new family of metrics 6t relates to √tψ through the formula exp（-δ^2t（x,y））=F[e^-tψ/pt（0）]（x-y）,where Y denotes the Fourier transform. Thus we obtain the following ＂Gaussian＂ representation of the tran- sition density： pt（x） = pt（O）e^-δ^2t（x,0） where pt（O） corresponds to a volume term related to √tψ and where an ＂exponential＂ decay is governed by 5t2. This gives a complete and new geometric, intrinsic interpretation of pt（x）.

关键词： transition function estimates Levy processes metric measure spaces heat kernel bounds in-finitely divisible distributions self-reciprocal distributions

marginal zone B cells are naturally reactive to collagen type II and are involved in the initiation of the immune response in collagen-induced arthritis

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Cellular & molecular Immunology 2011年第4期8卷 296-304页

作者： Cecilia Carnrot Kajsa E Prokopec Kristina Rasbo mikael CI Karlsson sandra Kleinau Department of Cell and molecular Biology Uppsala UniversityUppsalaSweden Department of medicine Unit of Clinical Allergy ResearchThe Karolinska InstituteSolnaSweden

Antibodies against type II collagen(CII)are essential for development of collagen-induced arthritis(CIA),but how and where the B-cell response to CII is initiated is not fully *** show here that naive DBA/1 mice display naturally reactive Igm and IgG anti-CII producing B cells prior to *** CII-reactive B cells were observed in the spleen and recognized as marginal zone(mZ)B *** CII immunization,CII-specific B cells expanded rapidly in the spleen,in contrast to the lymph nodes,with the initial response derived from mZ B cells and later by follicular(FO)B *** was evident despite that the mZ B cells were subject to stringent tolerance mechanisms by having a greater Fc gamma receptor IIb expression than the FO B ***,the mZ B cells migrated to the FO areas upon immunization,possibly providing antigen and activating FO T cells and subsequently FO B ***,around CIA onset increased numbers of IgG anti-CII producing FO B cells was seen in the spleen,which was dominated by IgG2a-and IgG2b-positive *** data demonstrate that CII-reactive mZ B cells are present before and expand after CII immunization,suggesting an initiating role of mZ B cells in the development of CIA.

关键词： arthritis B cells collagen type II ELISpot marginal zone mice