The past ice sheet dynamics and the timing of retreat events in the paleo-record in the Ross Sea is an issue still few understood. In order to contribute to this topic, we provide a multiproxy data from marine sediment archives (cores and box cores) collected in three sites in the Central Basin (Western Ross Sea, Antarctica). Each site recorded different environments, affected by different oceanographic conditions and sedimentary regime.
View Article and Find Full Text PDFStarting from 1952 C.E. more than 540 atmospheric nuclear weapons tests (NWT) were conducted in different locations of the Earth.
View Article and Find Full Text PDFThe study of airborne chemical markers is crucial for identifying sources of aerosols, and their atmospheric processes of transport and transformation. The investigation of free amino acids and their differentiation between the L- and D- enantiomers are even more important to understand their sources and atmospheric fate. Aerosol samples were collected with a high-volume sampler with cascade impactor at Mario Zucchelli Station (MZS) on the coast of the Ross Sea (Antarctica) for two summer campaigns (2018/19 and 2019/20).
View Article and Find Full Text PDFAtmospheric aerosols are important drivers of Arctic climate change through aerosol-cloud-climate interactions. However, large uncertainties remain on the sources and processes controlling particle numbers in both fine and coarse modes. Here, we applied a receptor model and an explainable machine learning technique to understand the sources and drivers of particle numbers from 10 nm to 20 μm in Svalbard.
View Article and Find Full Text PDFTen years of data of biogenic aerosol (methane sulfonic acid, MSA, and non-sea salt sulfate, nssSO) collected at Concordia Station in the East Antarctic plateau (75° 06' S, 123° 20' E) are interpreted as a function of the Southern Annular Mode (SAM), Chlorophyll-a concentration (Chl-a; a proxy for phytoplankton biomass), sea ice extent and area. It is possible to draw three different scenarios that link these parameters in early, middle, and late summer. In early summer, the biogenic aerosol is significantly correlated to sea ice retreats through the phytoplankton biomass increases.
View Article and Find Full Text PDFNear infrared (NIR)-resonant gold nanoparticles (AuNPs) hold great promise in cancer diagnostics and treatment. However, translating the theranostic potential of AuNPs into clinical applications still remains a challenge due to the difficulty to improve the efficiency and specificity of tumor delivery in vivo as well as the clearance from liver and spleen to avoid off target toxicity. In this study, endothelial colony forming cells (ECFCs) are exploited as vehicles to deliver AuNPs to tumors.
View Article and Find Full Text PDFShip traffic, population, infrastructure development, and mining activities are expected to increase in the Arctic due to its rising temperatures. This is expected to produce a major impact on aerosol composition. Metals contained in atmospheric particles are powerful markers and can be extremely helpful to gain insights on the different aerosol sources.
View Article and Find Full Text PDFThe Arctic is an important natural laboratory that is extremely sensitive to climatic changes and its monitoring is, therefore, of great importance. Due to the environmental extremes it is often hard to deploy sensors and observations are limited to a few sparse observation points limiting the spatial and temporal coverage of the Arctic measurement. Given these constraints the possibility of deploying a rugged network of low-cost sensors remains an interesting and convenient option.
View Article and Find Full Text PDFAn inductively coupled plasma sector field mass spectrometer (ICP-SFMS) was used to develop an analytical method for the fast determination of Na, Al, Sc, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Y, Mo, Cd, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Pb in Arctic size-segregated aerosol samples (PM), after microwave acidic digestion. The ICP-SFMS was coupled with a microflow nebulizer and a desolvation system for the sample introduction, which reduced the isobaric interferences due to oxides and the required volume of sample solutions, compared to the usual nebulization chamber methods. With its very low limit of detection, and taking into account the level of blanks, this method allowed the quantification of many metals in very low concentration.
View Article and Find Full Text PDFSporadic solar energetic particle (SEP) events affect the Earth's atmosphere and environment, in particular leading to depletion of the protective ozone layer in the Earth's atmosphere, and pose potential technological and even life hazards. The greatest SEP storm known for the last 11 millennia (the Holocene) occurred in 774-775 AD, serving as a likely worst-case scenario being 40-50 times stronger than any directly observed one. Here we present a systematic analysis of the impact such an extreme event can have on the Earth's atmosphere.
View Article and Find Full Text PDFIn the photothermal treatments (PTs) of tumor, the localization of a high number of near-infrared (NIR) absorbing gold nanoparticles in the tumor mass is still a challenging issue. Here, we propose a promising strategy to deliver therapeutic chitosan-coated gold nanoparticles to tumor cells as hidden cargo of Endothelial Colony Forming Cells (ECFCs) endowed with an innate tumor-tropism. Remarkably, ECFC gold enrichement doesn't affect cell viability and preserves the endothelial lineage characteristics such as capillary morphogenesis and cell migration.
View Article and Find Full Text PDFFive snow pits and five firn cores were sampled during the 2003-2004 Italian Antarctic Campaign at Talos Dome (East Antarctica), where a deep ice core (TALDICE, TALos Dome Ice CorE, 1650m depth) was drilled in 2005-2008 and analyzed for ionic content. Particular attention is spent in applying decontamination procedures to the firn cores, as core sections were stored for approximately 10years before analysis. By considering the snow pit samples to be unperturbed, the comparison with firn core samples from the same location shows that ammonium, nitrate and MSA are affected by storage post-depositional losses.
View Article and Find Full Text PDFRecently, the increasing interest in the understanding of global climatic changes and on natural processes related to climate yielded the development and improvement of new analytical methods for the analysis of environmental samples. The determination of trace chemical species is a useful tool in paleoclimatology, and the techniques for the analysis of ice cores have evolved during the past few years from laborious measurements on discrete samples to continuous techniques allowing higher temporal resolution, higher sensitivity and, above all, higher throughput. Two fast ion chromatographic (FIC) methods are presented.
View Article and Find Full Text PDFFrom January to December 2010, surface snow samples were collected with monthly resolution at the Concordia station (75°06'S, 123°20'E), on the Antarctic plateau, and analysed for major and trace elements in both dissolved and particulate (i.e. insoluble particles, >0.
View Article and Find Full Text PDFIce cores are widely used to reconstruct past changes of the climate system. For instance, the ice core record of numerous water-soluble and insoluble chemical species that are trapped in snow and ice offer the possibility to investigate past changes of various key compounds present in the atmosphere (i.e.
View Article and Find Full Text PDFA detailed ionic component record was performed on EPICA Dome C ice core (East Antarctica) to a depth of 3190 m using Ion Chromatography and Fast Ion Chromatography (FIC). At depths greater than 2800 m, the sulfate profile shows intense, sharp spikes which are not expected due to the smoothing of sulfate peaks by diffusion processes. Moreover, these spikes show an "anomalous" chemical composition (e.
View Article and Find Full Text PDFA method was developed for the quantitative determination of cations and anions in Antarctic ice cores at microgL(-1) and sub-microgL(-1) levels by ion chromatography (IC), after ultra-clean decontamination procedures. Strict manipulation and decontamination procedures were used in sub-sampling, in order to minimise sample contamination. Na+, NH4+, K+, Mg2+ and Ca2+ were determined by 12-min isocratic elution (H2SO4 eluent).
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