Time- and space-resolved spectroscopic characterization of laser-induced swine muscle tissue plasma

10 págs.; 12 figs.; 1 tab.The spatial-temporal evolution of muscle tissue sample plasma induced by a high-power transversely excited atmospheric (TEA) CO2 pulsed laser at vacuum conditions (0.1–0.01 Pa) has been investigated using high-resolution optical emission spectroscopy (OES) and imaging methods. The induced plasma shows mainly electronically excited neutral Na, K, C, Mg, H, Ca, N and O atoms, ionized C+, C2 +, C3 +, Mg+, Mg2 +, N+, N2 +, Ca+, O+ and O2 + species and molecular band systems of CN(B2Σ+–X2Σ+), C2(d3Πg–a3Πu), CH(B2Σ−–X2Π; A2Δ–X2Π), NH(A3Π–X3Σ−), OH(A2Σ+–X2 Σ+), and CaOH(B2Σ+–X2Σ+; A2Π–X2Σ+). Time-resolved two-dimensional emission spectroscopy is used to study the expanded distribution of different species ejected during ablation. Spatial and temporal variations of different atoms and ionic excited species are reported. Plasma parameters such as electron density and temperature were measured from the spatio-temporal analysis of different species. Average velocities of some plasma species were estimated. © 2015 Elsevier B.V. All rights reserved.We gratefully acknowledge the support received in part by the DGICYT (Spain) Project MICINN: CTQ2013-43086-P for this research. The authors wish to thank the Geomaterials2 Program (S2013/MIT 2914) supported by the Comunidad de Madrid and EU structural and cohesion funds (FSE and FEDER).Peer reviewe

Local and remote sources of airborne suspended particulate matter in the antarctic region

Quantification of suspended particulate matter (SPM) measurements-together with statistical tools, polar contour maps and backward air mass trajectory analyses-were implemented to better understand the main local and remote sources of contamination in this pristine region. Field campaigns were carried out during the austral summer of 2016-2017 at the "Gabriel de Castilla" Spanish Antarctic Research Station, located on Deception Island (South Shetland Islands, Antarctic). Aerosols were deposited in an air filter through a low-volume sampler and chemically analysed using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) and Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES). Elements such as Al, Ca, Fe, K, Mg, Na, P, S, Cu, Pb, Sr, Ti, Zn, Hf, Zr, V, As, Ti, Mn, Sn and Cr were identified. The statistical tools together with their correlations (Sr/Na, Al/Ti, Al/Mn, Al/Sr, Al/Pb, K/P) suggest a potentially significant role of terrestrial inputs for Al, Ti, Mn, Sr and Pb; marine environments for Sr and Na; and biological inputs for K and P. Polar contour graphical maps allowed reproducing wind maps, revealing the biological local distribution of K and P (penguin colony). Additionally, backward trajectory analysis confirmed previous affirmations and atmospheric air masses following the Antarctic circumpolar pattern

Single-cell strand sequencing of a macaque genome reveals multiple nested inversions and breakpoint reuse during primate evolution

Rhesus macaque is an Old World monkey that shared a common ancestor with human ∼25 Myr ago and is an important animal model for human disease studies. A deep understanding of its genetics is therefore required for both biomedical and evolutionary studies. Among structural variants, inversions represent a driving force in speciation and play an important role in disease predisposition. Here we generated a genome-wide map of inversions between human and macaque, combining single-cell strand sequencing with cytogenetics. We identified 375 total inversions between 859 bp and 92 Mbp, increasing by eightfold the number of previously reported inversions. Among these, 19 inversions flanked by segmental duplications overlap with recurrent copy number variants associated with neurocognitive disorders. Evolutionary analyses show that in 17 out of 19 cases, the Hominidae orientation of these disease-associated regions is always derived. This suggests that duplicated sequences likely played a fundamental role in generating inversions in humans and great apes, creating architectures that nowadays predispose these regions to disease-associated genetic instability. Finally, we identified 861 genes mapping at 156 inversions breakpoints, with some showing evidence of differential expression in human and macaque cell lines, thus highlighting candidates that might have contributed to the evolution of species-specific features. This study depicts the most accurate fine-scale map of inversions between human and macaque using a two-pronged integrative approach, such as single-cell strand sequencing and cytogenetics, and represents a valuable resource toward understanding of the biology and evolution of primate species

Horizontal Branch Stars: The Interplay between Observations and Theory, and Insights into the Formation of the Galaxy

We review HB stars in a broad astrophysical context, including both variable and non-variable stars. A reassessment of the Oosterhoff dichotomy is presented, which provides unprecedented detail regarding its origin and systematics. We show that the Oosterhoff dichotomy and the distribution of globular clusters (GCs) in the HB morphology-metallicity plane both exclude, with high statistical significance, the possibility that the Galactic halo may have formed from the accretion of dwarf galaxies resembling present-day Milky Way satellites such as Fornax, Sagittarius, and the LMC. A rediscussion of the second-parameter problem is presented. A technique is proposed to estimate the HB types of extragalactic GCs on the basis of integrated far-UV photometry. The relationship between the absolute V magnitude of the HB at the RR Lyrae level and metallicity, as obtained on the basis of trigonometric parallax measurements for the star RR Lyrae, is also revisited, giving a distance modulus to the LMC of (m-M)_0 = 18.44+/-0.11. RR Lyrae period change rates are studied. Finally, the conductive opacities used in evolutionary calculations of low-mass stars are investigated. [ABRIDGED]Comment: 56 pages, 22 figures. Invited review, to appear in Astrophysics and Space Scienc

Time and space resolved optical emission diagnostics of laser induced breakdown muscle tissue samples

XXIV Reunión Nacional de Espectroscopia-VIII Congreso Ibérico de Espectroscopia ; organizan Sociedad de Espectroscopia Aplicada (SEA) y la Universidad de la Rioja. P100The recent progress made in developing laser-induced breakdown spectroscopy (LIBS) has transformed this technique from an elemental analysis method to one that can be applied for the analysis of complex biological material or clinical specimens. The LIBS method has gained a reputation as a flexible and convenient technique for rapidly identification of unknown materials (chemical, biological or explosive). The plasma generated by LIBS technique on muscle tissue samples [1] was investigated using two high-power pulsed lasers (transverse excitation atmospheric CO2 and Nd:YAG lasers). A remarkable fact is the no influence of the laser wavelength on the observed spectral lines and molecular bands. The emission of the plasma shows excited neutral Na, K, C, Mg, H, N and O atoms, ionized C+, C2+, Mg+, N+ and O+ species and molecular band systems of CN(B2¿+ ¿ X2¿+), C2(d3¿g ¿ a3¿u), CH(A2¿ ¿ X2¿), NH(A3¿ ¿ X3¿-) and OH(A2¿ ¿ X2¿). For the assignment of the atomic/ionic lines we used the information tabulated in NIST [2]. The molecular bands were compared with the LIBS experiments obtained in our laboratory on different samples [3-6]. We focus our attention on the dynamics of the muscle tissue laser induced plasma species expanding into air (atmospheric pressure) or into vacuum (air pressures of 0.8 and 0.01 Pa). In conventional one dimensional optical emission spectroscopy (OES) studies, various plasma-plume segments were selected along the plume expansion axis and averaged over line-of-sight. This setup was easily transformed to a two-dimensional (2D) OES setup [7] by inserting a Dove prism between the focusing and collimating lenses. Time-integrated and time-resolved 2D OES plasma profiles were recorded as a function of emitted wavelength and distance from the target. Different plasma parameters such as velocities, temperatures and electron densities were evaluated using OES. The temporal behaviour of specific lines of atomic/ionic lines was characterized.This work was partially supported by the MICINN (Spain, Ministerio de Ciencia e Innovación), project CTQ2010-15680, Autónoma University of Madrid, project CEMU-2012-003 and Complutense University of Madrid, grant CCG10-UCM/PPQ-4713.Peer Reviewe

Trace Elements in Speleothems as Indicators of Past Climate and Karst Hydrochemistry: A Case Study from Kaite Cave (N Spain

A stalagmite that grew during the Holocene (between 4.9 and 0.9 ka BP) in Kaite Cave (Ojo Guareña Karst Complex, Burgos, N Spain) has been analyzed by Laser-Induced Breakdown Spectroscopy (LIBS) with the aim of reconstructing secular variations in the hydrochemistry of the karst system, in turn related to changes in the environment outside the cave. LIBS analyses yield significant changes in Mg/Ca and Sr/Ca intensity ratios through the stalagmite, which reveal consistent trends and patterns at decadal to centennial scales. The origin of the observed changes in Mg/Ca and Sr/Ca ratios is discussed in the framework of the cave system and the regional climatic variability, particularly the changes in precipitation