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1.
We studied interactions of nitromusk compounds musk ketone and musk xylene and polycyclic musks Galaxolide trade mark (HHCB), Celestolide trade mark (ADBI), Tetralide trade mark (AHTN), and Traseolide trade mark (AITI) with multixenobiotic resistance (mxr) transporters in gill tissue of the marine mussel Mytilus californianus (Conrad, 1837). A competitive substrate transport test with rhodamine B was used to assay modulation of transport activity by musks. All tested musks inhibited the transport activity in the low microm range as indicated by increased accumulation of rhodamine B in the tissue. Compared to known substrates of mxr transporters, the effective concentration range was similar to quinidine and about 100 times higher than verapamil. Musk ketone and musk xylene also inhibited efflux of rhodamine B from gill tissue which was loaded with the dye and subsequently incubated with these compounds. Synthetic musk compounds are persistent environmental pollutants in aquatic environments with a high potential to bioaccumulate. As potent inhibitors of mxr transporters they may also play a role as chemosensitizers that enable toxic mxr substrates to accumulate in cells of aquatic organisms. 相似文献
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Regoli F Gorbi S Frenzilli G Nigro M Corsi I Focardi S Winston GW 《Marine environmental research》2002,54(3-5):419-423
An integrate approach will be discussed for investigations on oxidative stress in xenobiotic toxicity. While the analysis of individual antioxidants is useful for their sensitivity and to understand the mode of action of a stressor, the integration with the analysis of the total antioxidant capacity provides a more holistic assessment of the overall biological significance of such variations. TOSC has a greater predictive value on the health condition of the organisms and allows to discriminate the different role of specific ROS in oxidative stress syndrome. 相似文献
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Luigi Bruno Michela Marchi Ilaria Bertolini Guido Gottardi Alessandro Amorosi 《第四纪科学杂志》2020,35(4):559-571
Paleosols are recurrent features in alluvial successions and provide information about past sedimentary dynamics and climate change. Through sedimentological analysis on six sediment cores, the mud-dominated succession beneath the medieval ‘Two Towers’ of Bologna was investigated down to 100 m depth. A succession of weakly developed paleosols (Inceptisols) was identified. Four paleosols (P1, P2, P3 and PH) were radiocarbon-dated to 40–10 cal ka bp . Organic matter and CaCO3 determinations indicate low groundwater levels during soil development, which spanned periods < 5 ka. The development and burial of soils, which occurred synchronously in the Bologna region and in other sectors of the Po Plain, are interpreted to reflect climatic and eustatic variations. Climatic oscillations, at the scale of the Bond cycles, controlled soil development and burial during Marine Isotope Stage (MIS) 3 (P1 and P2). Rapid sea-level oscillations probably induced soil development at the MIS 3/2 transition (P3) and favored burial of PH after 10 ka bp . Weakly developed paleosols in alluvial successions can provide clues to millennial-scale climatic and environmental variations. In particular, the paleosol-bearing succession of the Po Plain represents an unprecedent record of environmental changes across the Late Pleistocene (MIS 3 and 2) in the Mediterranean region. 相似文献
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A. Bragaglia F. R. Ferraro F. Fusi Pecci R. Buonanno C. E. Corsi I. Ferraro G. Iannicola 《Journal of Astrophysics and Astronomy》1987,8(1):57-68
Using a first approximation to the Hubble space telescope point-spread function, the problems concerning observation and reduction
of globular clusters in the Andromeda nebula are analysed through a simulation procedure in order to study the feasibility
of accurate photometry of individual stars in the clusters. 相似文献
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Simultaneous identification of the pollutant release history and the source location in groundwater by means of a geostatistical approach 总被引：4，自引：1，他引：3
Ilaria Butera Maria Giovanna Tanda Andrea Zanini 《Stochastic Environmental Research and Risk Assessment (SERRA)》2013,27(5):1269-1280
This paper describes an innovative procedure that is able to simultaneously identify the release history and the source location of a pollutant injection in a groundwater aquifer (simultaneous release function and source location identification, SRSI). The methodology follows a geostatistical approach: it develops starting from a data set and a reliable numerical flow and transport model of the aquifer. Observations can be concentration data detected at a given time in multiple locations or a time series of concentration measurements collected at multiple locations. The methodology requires a preliminary delineation of a probably source area and results in the identification of both the sub-area where the pollutant injection has most likely originated, and in the contaminant release history. Some weak hypotheses have to be defined about the statistical structure of the unknown release function such as the probability density function and correlation structure. Three case studies are discussed concerning two-dimensional, confined aquifers with strongly non-uniform flow fields. A transfer function approach has been adopted for the numerical definition of the sensitivity matrix and the recent step input function procedure has been successfully applied. 相似文献
7.
Geoarchaeological research, integrating traditional excavations, and ground truthing with intensive geophysical surveys, aerial photography, and GIS‐based data processing, has revealed the full intramural plan of the abandoned Roman city of Ammaia in central Portugal. Although this multidisciplinary effort also focussed on understanding the town/territory relationships and the system of resource exploitation, this paper presents the most important results from fieldwork in the central monumental area of the town, the Roman Forum. Here, excavations, geomorphological survey, and an array of geophysical methods illuminate the long history of the site, from the first settlement and monument‐building phases in early Imperial times, to the ongoing post‐abandonment processes. This paper discusses some of the benefits of compiling these complementary data sets and proposes the use of a wide array of approaches in order to achieve full understanding of the complex topography and evolution of a classical urban site. It further demonstrates the need for effective stratigraphical control and geomorphological analysis of crucial areas revealed by high‐quality geophysics. 相似文献
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Borja A Barbone E Basset A Borgersen G Brkljacic M Elliott M Garmendia JM Marques JC Mazik K Muxika I Magalhães Neto J Norling K Rodríguez JG Rosati I Rygg B Teixeira H Trayanova A 《Marine pollution bulletin》2011,62(3):499-513
In recent times many benthic indices have been proposed to assess the ecological quality of marine waters worldwide. In this study we compared single metrics and multi-metric methods to assess coastal and transitional benthic status along human pressure gradients in five distinct environments across Europe: Varna bay and lake (Bulgaria), Lesina lagoon (Italy), Mondego estuary (Portugal), Basque coast (Spain) and Oslofjord (Norway). Hence, 13 single metrics (abundance, number of taxa, and several diversity and sensitivity indices) and eight of the most common indices used within the European Water Framework Directive (WFD) for benthic assessment were selected: index of size spectra (ISS), Benthic assessment tool (BAT), Norwegian quality index (NQI), Multivariate AMBI (M-AMBI), Benthic quality index (BQI), (Benthic ecosystem quality index (BEQI), Benthic index based on taxonomic sufficiency (BITS), and infaunal quality index (IQI). Within each system, sampling sites were ordered in an increasing pressure gradient according to a preliminary classification based on professional judgement. The different indices are largely consistent in their response to pressure gradient, except in some particular cases (i.e. BITS, in all cases, or ISS when a low number of individuals is present). Inconsistencies between indicator responses were most pronounced in transitional waters (i.e. IQI, BEQI), highlighting the difficulties of the generic application of indicators to all marine, estuarine and lagoonal environments. However, some of the single (i.e. ecological groups approach, diversity, richness) and multi-metric methods (i.e. BAT, M-AMBI, NQI) were able to detect such gradients both in transitional and coastal environments, being these multi-metric methods more consistent in the detection than single indices. This study highlights the importance of survey design and good reference conditions for some indicators. The agreement observed between different methodologies and their ability to detect quality trends across distinct environments constitutes a promising result for the implementation of the WFD’s monitoring plans. Moreover, these results have management implications, regarding the dangers of misclassification, uncertainty in the assessment, use of conflicting indices, and testing and validation of indices. 相似文献
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André C. Colonese Giovanni Zanchetta Catherine Perlès Russell N. Drysdale Giuseppe Manganelli Ilaria Baneschi Elissavet Dotsika Hélène Valladas 《Quaternary Research》2013
This paper investigates the stable isotopic composition from late Pleistocene–Holocene (~ 13 to ~ 10.5 cal ka BP) shells of the land snail Helix figulina, from Franchthi Cave (Greece). It explores the palaeoclimatic and palaeoenvironmental implications of the isotope palaeoecology of archaeological shells at the time of human occupation of the cave. Modern shells from around the cave were also analysed and their isotopic signatures compared with those of the archaeological shells. The carbon isotope composition of modern shells depicts the consumption of C3 vegetation. Shell oxygen isotopic values are consistent with other Mediterranean snail shells from coastal areas. Combining empirical linear regression and an evaporative model, the δ18Os suggest that modern snails in the study area are active during periods of higher relative humidity and lower rainfall δ18O, probably at night. Late glacial and early Holocene δ18Os show lower values compared to modern ones. Early Holocene δ18Os values likely track enhanced moisture and isotopic changes in the precipitation source. By contrast, lower late glacial δ18O could reflect lower temperatures and δ18Op, compared to the present day. Shell carbon isotope values indicate the presence of C3 vegetation as main source of carbon to late glacial and early Holocene snails. 相似文献
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Francesco Di Benedetto Ilaria Bencistà Francesco D’Acapito Silvia Frizzera Andrea Caneschi Massimo Innocenti Alessandro Lavacchi Giordano Montegrossi Werner Oberhauser Maurizio Romanelli Herbert Dittrich Luca A. Pardi Gerold Tippelt Georg Amthauer 《Physics and Chemistry of Minerals》2016,43(8):535-544
The successful synthesis of nanoparticles of Fe-bearing kuramite, (Cu,Fe)3SnS4, is reported in this study. Nanocrystalline powders were obtained through a mild, environmentally friendly and scalable solvothermal approach, in a single run. The sample was the object of a multidisciplinary investigation, including X-ray diffraction and absorption, scanning electron microscopy and microanalysis, electron paramagnetic resonance, diffuse reflectance and Mössbauer spectroscopy as well as SQUID magnetometry. The nanoparticles consist of pure Fe-bearing kuramite, exhibiting tetragonal structure. The valence state of the metal cations was assessed to be Cu+, Sn4+ and Fe3+. The material presents a band gap value of 1.6 eV, which is fully compatible with solar cell applications. The uptake of Fe by nanokuramite opens a compositional field where the physical properties can be tuned. We thus foster the application of Fe-bearing nanokuramite for photovoltaics and energy storage purposes. 相似文献