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Coupling textural and stable-isotope variations in fluvial stromatolites:Comparison of Pleistocene and recent records in NE Spain

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Journal of Palaeogeography 2019年第2期8卷 150-169页

作者： C.Arenas M.C.osácar L.Auqué C.Sancho Department of Earth Sciences University of Zaragoza Geotransfer Group and Institute for Research on Environmental Sciences of Aragón(IUCA)

Textural and stable isotopic features of two middle Pleistocene fluvial stromatolite profiles are compared to a recent stromatolite,both formed in the River Piedra system(NE Spain),to test the reliability of climatic,hydrologic and depositional information derived from ancient *** Pleistocene stromatolites formed in a multi-domed,highly-inclined *** recent stromatolite also formed in a highly-inclined cascade of the River Piedra,the sedimentary conditions of which were periodically examined between the years 2000 and *** Pleistocene stromatolites are formed of an alternation of 1) thin large-crystal laminae(type A),with elongated crystals up to 1 mm long,and 2) thick small-crystal laminae(type B),consisting of cyanobacterial fan-and bushshaped *** textural and isotopic comparison with the recent stromatolite shows that each A–B couplet corresponds to one *** type-A laminae are comparable to the macrocrystalline laminae that occur in the cool-period deposits of the recent stromatolite,and the type-B laminae are comparable to the warm-period deposits of the recent *** temperatures(Tw),calculated from δ^(18)o_(calcite) and present measures of δ^(18)o_(water),were similar in the Pleistocene and recent specimens,and close to the measured river ***,the Pleistocene stromatolites formed not far from isotopic equilibrium,as did the recent *** Pleistocene δ^(18) o_(calcite) biannual oscillation is wider in amplitude than in the recent stromatolite,which suggests larger differences in Tw through the year in the Pleistocene than at *** Pleistocene δ^(13)C_(calcite) does not show any pattern;and the values are slightly higher than the recent *** co-evolution of δ^(18)o and δ^(13)C is parallel in the Pleistocene stromatolites,matching the recent stromatolite *** results and their comparison with other ancient examples prove that textural and isotopic features in ancient stromatolites

关键词： Tufa Recent and ancient stromatolites Stable isotopes Biotic and abiotic laminae Intra-annual and inter-annual water temperature variations

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Sources,characteristics,toxicity,and control of ultrafine particles:An overview

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Geoscience frontiers 2022年第1期13卷 512-526页

作者： Andrea L.Moreno-Ríos Lesly P.Tejeda-Benítez Ciro f.Bustillo-Lecompte Department of Civil and Environmental Universidad de la CostaCUCCalle 58#55–66BarranquillaAtlánticoColombia Research Group in Biomedical Toxicological and Environmental Sciences(Biotoxam)University of CartagenaCampus of ZaragocillaCartagenaColombia School of occupational and Public Health Ryerson University350 Victoria StreetTorontoON M5B 2K3Canada

Air pollution by particulate matter(PM)is one of the main threats to human health,particularly in large cities where pollution levels are continually *** to their source of emission,geography,and local meteorology,the pollutant particles vary in size and *** particles are conditioned to the aerodynamic diameter and thus classified as coarse(2.5–10μm),fine(0.1–2.5μm),and ultrafine(of toxicity becomes greater for smaller *** particles can get into the lungs and translocate into vital organs due to their size,causing significant human health ***,PM pollutants have been linked to respiratory conditions,genotoxic,mutagenic,and carcinogenic activity in human *** paper presents an overview of emission sources,physicochemical characteristics,collection and measurement methodologies,toxicity,and existing control mechanisms for ultrafine particles(UfPs)in the last fifteen years.

关键词： Particulate matter Ultrafine particles Air pollution Toxicity Measurement methodologies

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finite-Size Conformational Transitions: A Unifying Concept Underlying Chromosome Dynamics

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Communications in Theoretical Physics 2014年第10期61卷 607-616页

作者： Bertrand R.caré Pascal carrivain Thierry forné Jean-Marc Victor Annick Lesne Laboratoire de Physique Théorique de la Matière Condensée CNRS UMR 7600UPMC University Paris 06F-75005ParisFrance CNRS GDR 3536 UPMC University Paris 06F-75005ParisFrance Institut de Génétique Humaine CNRS UPR 1142 MontpellierFrance Institut de Génétique Moléculaire de Montpellier CNRS UMR 5535University of MontpellierMontpellierFrance Kavli Institute for Theoretical Physics China CAS

Investigating average thermodynamic quantities is not sufficient to understand conformational transitions of a finite-size polymer. We propose that such transitions are better described in terms of the probability distribution of some finite-size order parameter, and the evolution of this distribution as a control parameter varies. We demonstrate this claim for the coil-globule transition of a linear polymer and its mapping onto a two-state model. In a biological context, polymer models delineate the physical constraints experienced by the genome at different levels of organization,from DNA to chromatin to chromosome. We apply our finite-size approach to the formation of plectonemes in a DNA segment submitted to an applied torque and the ensuing helix-coil transition that can be numerically observed, with a coexistence of the helix and coil states in a range of parameters. Polymer models are also essential to analyze recent in vivo experiments providing the frequency of pairwise contacts between genomic loci. The probability distribution of these contacts yields quantitative information on the conformational fluctuations of chromosome regions. The changes observed in the shape of the distribution when the cell type or the physiological conditions vary may reveal an epigenetic modulation of the conformational constraints experienced by the chromosomes.

关键词： coil-globule transition helix-coil transition chromosome conformational capture two-state model

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Hepatocellular carcinoma and food contamination: ochratoxin A as a great prompter

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World Journal of Gastroenterology 2013年第24期19卷 3723-3725页

作者： Raphael Jf felizardo Niels os Cmara Division of Nephrology Department of Medicine Federal University of Sao PauloSao Paulo CEP 05508-900 Brazil Department of Immunology Institute of Biomedical Sciences University of S o PauloSao Paulo CEP 05508-900 Brazil

ochratoxin A (oTA) is a secondary metabolite of Asper-gillus and Penicillium, microorganisms that can be haz-ardous to health when present as food contaminants. oTA is a potent member of a group of mycotoxins. Prolonged exposure to mycotoxins in the diet is related to cancer, among other diseases. Hepatocellular car-cinoma (HCC) accounts for 70%-90% of primary liver cancers and is the third leading cause of cancer-related deaths worldwide. In a recent study, Ibrahim et al proposed a correlation between the incidence of HCC and contamination with oTA. Analysis of oTA in serum samples showed that HCC patients had the highest incidence of oTA of the subjects examined (5-fold higher than that of the control group). oTA levels were significantly increased in HCC patients. This study demonstrates that chronic exposure to high levels of oTA may be associated with a high risk of liver cancer development. future epidemiologic studies of HCC should focus on good practices in food preparation, food storage and the consumption of oTA-containing foods.

关键词： ochratoxin A Mycotoxin food contamination Hepatocellular carcinoma Liver cancer Egypt

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Use of wild trout for PBDE assessment in freshwater environments: Review and summary of critical factors

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Emerging Contaminants 2015年第1期1卷 54-63页

作者： Juan M.Ríos Nerina B.Lana Paula Berton Néstor f.Ciocco Jorgelina C.Altamirano Laboratorio de Química Ambiental Instituto Argentino de NivologíaGlaciología y Ciencias Ambientales(IANIGLA)-CONICETMendozaP.O Box 1315500 MendozaArgentina facultad de Ciencias Exactas y Naturales Universidad Nacional de CuyoPadre J.Contreras 13005500 MendozaArgentina Instituto Argentino de Investigaciòn de ZonasÁridas(IADIZA)-CoNICET MendozaP.O Box 5075500 MendozaArgentina

Certain wild animals represent sentinels to address issues related to environmental pollution,since they can provide integrative data on both pollutant exposure and biological *** their technological benefits,PBDEs are considered a threat to environmental health due to their persistence,toxicity,and capacity to be *** pollutants have been found geographically widespread in fish,particularly in predator species such as *** aim of this work is to critically review the applicability and usefulness of wild trout for assessing PBDEs in freshwater *** reports include data from highly industrialized areas as well as areas from remote regions with relatively low human activity,including European and North American great lakes and freshwater environments in Europe,Greenland,subarctic areas and Patagonia,respectively.A summary of relevant factors were grouped into organism-specific factors(food habits,age,size,lipid content,sex and reproduction,tissue type,mechanism of contaminant uptake and metabolism),and PBDE levels in the surrounding environment(sediment).five wild trout species[rainbow trout(oncorhynchus mykiss),brown trout(Salmo trutta),lake trout(Salvelinus namaycush),arctic char(Salvelinus alpinus),and brook trout(Salvelinus fontinalis)],collected worldwide within the 1994 to present time frame,were *** techniques(principal component analysis-PCA)and mapping approach,showed clear differences in geographic distribution patterns of PBDE levels in trout depending on the region studied:wild trout from European and North American great lakes have the highest PBDE *** pattern could be due to high industrial activity at these locations.A correlational approach used to explore intraspecific relationships between PBDE levels and morphometry,showed positive relationships only for brown ***,brown trout showed the highest trout-to-sediment ratios,which is suggestive of a relatively greater capa

关键词： Critical factors freshwater environments PBDE Trout Global hotspots

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Biorefinery of Rice Husk to obtain functionalized Bioactive Compounds

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Journal of Renewable Materials 2019年第4期7卷 313-324页

作者： M.Lopretti N.Lecot A.Rodriguez G.Lluberas f.orozco L.Bolaños G.Montes De oca H.Cerecetto J.Vega-Baudrit Laboratorio de Técnicas Nucleares Aplicadas a Bioquímica y Biotecnología Centro de Investigaciones Nucleares-Facultad de CienciasMataojo 2055Montevideo CP 11400Uruguay Área de Radiofarmacia Centro de Investigaciones Nucleares-Facultad de CienciasMataojo 2055Montevideo CP 11400Uruguay Química Bioanalítica Instituto Polo Tecnológico de Pando-Facultad de QuímicaUdelaRBy Pass de Pando y Ruta 8Pando-Canelones CP 91000Uruguay Laboratorio de Nacional de Nanotecnología-CeNAT-CoNARE Costa Rica 1174-1200San JoséCP 10109Costa Rica Laboratorio de Polímeros POLIUNA-Escuela de Química Universidad NacionalHerediaSan JoséCP 86-3000Costa Rica

The biomass industrialization valorisation of grains and cereals is considered an opportunity for the countries where agro-industrial activity is one of its main economic activities,rendering new higher-value products with a concomitant solution to waste accumulation *** that end,in this work we describe and characterise bioactive compounds generation from rice husk by semisolid fermentation,obtained from 500 g of the material at room temperature and 60%humidity with mixed cultures of Phanerochaete chrysosporium and Gloeophyllum *** extract was evaluated in different situations:murine mammary tumour cells(4T1),normal cells(NIH 3T3)and in Lactobacillus acidophilus,and Trichoderma *** results exhibited that the extract inhibited 4T1 cells at concentrations higher than 20μg/mL,but did not inhibit normal cells,and displayed germicide activity after 3 days *** propose that these functionalized compounds have a potential application in industry/agriculture/medicine obtained from rice husk waste.

关键词： Biorefinery rice husk bioactive compounds valorisation of biomass veratryl alcohol

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Designing a Scar molecular marker for monitoring Trichoderma cf. harzianum in experimental communities

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2014年第11期15卷 966-978页

作者： Gabriel PéREZ Valentina VERDEJo Clarissa GoNDIM-PoRTo Julieta oRLANDo Margarita carú Department of Ecological Sciences Faculty of SciencesUniversity of Chile

Several species of the fungal genus Trichoderma establish biological interactions with various micro- and macro-organisms. Some of these interactions are relevant in ecological terms and in biotechnological applications, such as biocontrol, where Trichoderma could be considered as an invasive species that colonizes a recipient community. The success of this invasion depends on multiple factors, which can be assayed using experimental communities as study models. Therefore, the aim of this work is to develop a species-specific sequence-characterized amplified region （Scar） marker to monitor the colonization and growth of T. cf. harzianum when it invades experi- mental communities. for this study, 16 randomly amplified polymorphic DNA （RAPD） primers of 10-mer were used to generate polymorphic patterns, one of which generated a band present only in strains of T. cf. harzianum. This band was cloned, sequenced, and five primers of 20-23 mer were designed. Primer pairs 2f2/2R2 and 2f2/2R3 successfully and specifically amplified fragments of 278 and 448 bp from the T. cf. harzianum BpT10a strain DNA, respectively. Both primer pairs were also tested against the DNA from 14 strains of T. cf. harzianum and several strains of different fungal genera as specificity controls. only the DNA from the strains of T. cf. hat-zianum was successfully amplified. Moreover, primer pair 2f2/2R2 was assessed by quantitative real-time polymerase chain reaction （PCR） using fungal DNA mixtures and DNA extracted from fungal experimental communities as templates. T. cf. harzianum was detectable even when as few as 100 copies of the Scar marker were available or even when its population represented only 0.1% of the whole community.

关键词： Tnchoderma cf. harzianum Sequence-characterized amplified region (Scar) Molecular marker Experimental fungal communities

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精神病的跨诊断维度:对精神疾病的分类学与研究的意义（英文）

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上海精神医学 2015年第2期27卷 82-86页

作者： Jim VAN os Maastricht University Medical Centre South Limburg Mental Health Research and Teaching Network King’s College London King’s Health Partners Department of Psychosis Studies Institute of Psychiatry

如果精神病是一种跨诊断的维度,精神病性症状的出现受动态变化的情境和情感因素左右,而后者又是可治疗的,那么目前精神科疾病的分类学和治疗研究的方法可能需要修改。迄今为此,无论在临床工作上还是在疾病概念上,占主导地位的方法是将... 详细信息

如果精神病是一种跨诊断的维度,精神病性症状的出现受动态变化的情境和情感因素左右,而后者又是可治疗的,那么目前精神科疾病的分类学和治疗研究的方法可能需要修改。迄今为此,无论在临床工作上还是在疾病概念上,占主导地位的方法是将精神病性症状置于精神分裂症的框架中。然而,终生患病率为1%的精神分裂症只代表了部分预后不佳的精神病谱系障碍,而后者发生更多,终生患病率为3.5%。因此,精神分裂症的研究结果可能反映了预后相关的机制,而非精神病和其他症状维度之间本质上的相关性。同样,常见的非精神病性精神障碍中高达30%的个体有阈下精神病性症状,他们会被归于精神病的跨诊断维度之下,这些精神症状还会影响临床严重程度和治疗有效性。上述发现也同样提示武断区分"精神病性"与"非精神病性"的做法妨碍了临床实践和研究。精神病学诊断手册可以借鉴跨诊断维度(包括精神病的跨诊断维度)的体系。引入跨诊断维度,则既能根据原则进行分类诊断(即疾病分组的特异性),又可结合个体特有的多维度综合评分(即个体特异性)。这样的益处在于促使人们思考在精神病理学中症状之间是如何动态地交互作用的,并思考社会环境是如何影响精神病理症状的。

关键词：精神病分类学尺寸疾病精神分裂症临床实践情感因素精神障碍

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Growing arugula plants using aeroponic culture with an automated irrigation system

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International Journal of Agricultural and Biological Engineering 2020年第3期13卷 52-56页

作者： Jhon D.Ríos Salazar John E.Candelo-Becerra fredy E.Hoyos Velasco Escuela de física Facultad de CienciasUniversidad Nacional de ColombiaSede MedellínColombia Departamento de Energía Eléctrica y Automática Facultad de MinasUniversidad Nacional de ColombiaSede MedellínColombia

The paper presents an efficient form of growing arugula plants by means of automatic control of an aeroponic culture irrigation *** system considers a reprogrammable electronic circuit that uses software to generate different irrigation cycles to obtain an adequate growth of arugula *** show how different samples grown in a greenhouse had the same growth behavior as field-grown samples during the test *** was possible to obtain a more efficient and sustained five-week production to supply consumers by having a continuous cycle irrigation system,which was operated for 35 *** growth and number of leaves were maintained in a similar way for different plants *** grow similarly,but some of them showed size differences during the five weeks.

关键词： aeroponic culture arugula plants food production irrigation systems smart system

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Diversity and seasonal variation of ground and understory spiders from a tropical mountain cloud forest

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Insect Science 2020年第4期27卷 826-844页

作者： Emmanuel f.Campuzano Guillermo Ibarra-Nunez Salima Machkour-M Rabet Alejandro Moron-Rios Maria Luisa Jimenez Colegio de la frontera Sur(ECosUR) Unidad TapachulaTapachulaChiapasMexico ECosUR Unidad ChetumalChetumalQuintana RooMexico ECosUR Unidad CampecheCampecheCampecheMexico Centro de Investigaciones Biologicas del Noroeste(CIBNoR) La PazBaja California SurMexico

We made intensive samplings to study the seasonal response of spiders across different forest strata(ground and understory)in a tropical mountain cloud forest from *** sampled spiders from ten plots in six sampling events during the dry and rainy season,to analyze their abundance,structure(distribution of abundance among species),diversity and the response of the five dominant species at each *** demonstrated that seasonal patterns of spider communities differed among strata,revealing a complex spatiotemporal ***,structure,diversity of ground spiders,as well as the responses of four dominant species at this stratum,showed low seasonal *** contrast,a strong seasonal variation was observed for the understory assemblage,with lowest abundance and highest diversity in the rainy season,and different assemblage structures for each *** patterns of each assemblage seem linked to the responses of their dominant *** found high co-occurrence among most of the ground dominant species with similar habitat use and with multivoltine patterns,contrasting with low co-occurrence among most of the understory dominant species with similar habitat use and univoltine *** results showed that the spiders’assemblages of tropical mountain cloud forest(opposed to what is found in temperate and boreal forests)increase their species richness with the height,and that their responses to seasonal change differ between *** programs of these habitats should consider the spatial and temporal variations found here,as a better understanding of their ecological dynamics is required to support their sustainable management.

关键词： community structure El Triunfo Biosphere Reserve interspecific competition Mexico temporal change vertical stratification

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