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The Las Cuevas Canyon at Los Toldos locality (Santa Cruz, Argentina) has played a prominent and controversial role in the debate about the peopling of America. In spite of the high concentration of paintings in Los Toldos, its rock art has not been included as a significant variable in the discussion. This work introduces original information from the systematic study of six archaeological sites at the Las Cuevas Canyon with the aim of laying the foundations for a comparative study at local and regional scales. For this purpose, aspects such as the distribution of motifs, the superimpositions, and the size of the hand stencils are evaluated. The results shed light on the practices of different social actors in the canyon, and allow us to propose a sequence of rock art production. The discussion is contextualized within the regional archaeological scholarship of southern Patagonia.
The stellar occultation technique is a powerful tool to study distant small solar system bodies. Currently, around 2 500 trans-neptunian objects (TNOs) and Centaurs are known. With the astrometry from Gaia and large surveys like the Large Synoptic Survey Telescope (LSST), accurate predictions of occultation events will be available to tens of thousands of TNOs and Centaurs and boost the knowledge of the outer solar system.
We present an in-depth study of metal-poor stars, based high resolution spectra combined with newly released astrometric data from Gaia, with special attention to observational uncertainties. The results are compared to those of other studies, including Gaia benchmark stars. Chemical evolution models are discussed, highlighting few puzzles that are still affecting our understanding of stellar nucleosynthesis and of the evolution of our Galaxy.
In this work we present chemical abundances of heavy elements (Z>28) for a homogeneous sample of 1059 stars from HARPS planet search program. We also derive ages using parallaxes from Hipparcos and Gaia DR1 to compare the results. We study the [X/Fe] ratios for different populations and compare them with models of Galactic chemical evolution. We find that thick disk stars are chemically disjunt for Zn adn Eu. Moreover, the high-alpha metal-rich population presents an interesting behaviour, with clear overabundances of Cu and Zn and lower abundances of Y and Ba with respect to thin disk stars. Several abundance ratios present a significant correlation with age for chemically separated thin disk stars (regardless of their metallicity) but thick disk stars do not present that behaviour. Moreover, at supersolar metallicities the trends with age tend to be weaker for several elements.
In connection with long on-orbit European space satellite Gaia and the opportunity that now provides ESA, to use the results of observations of the space telescope, we would like to present some results of our long-term observations of the major planets satellites at Pulkovo Observatory. We hope to translate into reality these opportunities, namely the use of new observations and new ephemeris and a practical possibility of a new reduction for modern and old observations. The essential facilities can appear in the space, we give the shortest presentation of space project Orbital Stellar Stereoscopic Observatory.
The American Heart Association (AHA; Dallas, Texas USA) and European Resuscitation Council (Niel, Belgium) cardiac arrest (CA) guidelines recommend the intraosseous (IO) route when intravenous (IV) access cannot be obtained. Vasopressin has been used as an alternative to epinephrine to treat ventricular fibrillation (VF).
Limited data exist on the pharmacokinetics and resuscitative effects of vasopressin administered by the humeral IO (HIO) route for treatment of VF. The purpose of this study was to evaluate the effects of HIO and IV vasopressin, on the occurrence, odds, and time of return of spontaneous circulation (ROSC) and pharmacokinetic measures in a swine model of VF.
Twenty-seven Yorkshire-cross swine (60 to 80 kg) were assigned randomly to three groups: HIO (n=9), IV (n=9), and a control group (n=9). Ventricular fibrillation was induced and untreated for two minutes. Chest compressions began at two minutes post-arrest and vasopressin (40 U) administered at four minutes post-arrest. Serial blood specimens were collected for four minutes, then the swine were resuscitated until ROSC or 29 post-arrest minutes elapsed.
Fisher’s Exact test determined ROSC was significantly higher in the HIO 5/7 (71.5%) and IV 8/11 (72.7%) groups compared to the control 0/9 (0.0%; P=.001). Odds ratios of ROSC indicated no significant difference between the treatment groups (P=.68) but significant differences between the HIO and control, and the IV and control groups (P=.03 and .01, respectively). Analysis of Variance (ANOVA) indicated the mean time to ROSC for HIO and IV was 621.20 seconds (SD=204.21 seconds) and 554.50 seconds (SD=213.96 seconds), respectively, with no significant difference between the groups (U=11; P=.22). Multivariate Analysis of Variance (MANOVA) revealed the maximum plasma concentration (Cmax) and time to maximum concentration (Tmax) of vasopressin in the HIO and IV groups was 71753.9 pg/mL (SD=26744.58 pg/mL) and 61853.7 pg/mL (SD=22745.04 pg/mL); 111.42 seconds (SD=51.3 seconds) and 114.55 seconds (SD=55.02 seconds), respectively. Repeated measures ANOVA indicated no significant difference in plasma vasopressin concentrations between the treatment groups over four minutes (P=.48).
The HIO route delivered vasopressin effectively in a swine model of VF. Occurrence, time, and odds of ROSC, as well as pharmacokinetic measurements of HIO vasopressin, were comparable to IV.
BurgertJM, JohnsonAD, Garcia-BlancoJ, FultonLV, LoughrenMJ. The Resuscitative and Pharmacokinetic Effects of Humeral Intraosseous Vasopressin in a Swine Model of Ventricular Fibrillation. Prehosp Disaster Med. 2017;32(3):305–310.
We describe the preparation of charts and positions for 1035 cool red giant carbon stars discovered by the authors in the Large Magellanic Cloud (LMC). Not considered here are Small Magellanic Cloud (SMC) carbon stars, nor the M-type giants found in the LMC and SMC (Blanco et al. 1980, Blanco & McCarthy 1983). Charts of the C stars discovered are available in three formats: (a) 12 charts contain 186 C stars discovered in three central LMC regions (Blanco et al. 1980); (b) charts of C and late M stars in 52 LMC regions; these charts will not be published but are available from the authors (Blanco & McCarthy 1983, discussion); and (c) charts for 849 individual C stars in 49 regions of LMC (Blanco & McCarthy 1990).
Next space missions will investigate the possibility of extinct or extant life on Mars. Studying the infrared spectral modifications, induced by thermal processing on different carbonate samples (recent shells and fossils of different ages), we developed a method able to discriminate biogenic carbonates from their abiogenic counterparts. The method has been successfully applied to microbialites, i.e. bio-induced carbonates deposits, and particularly to stromatolites, the laminated fabric of microbialites, some of which can be ascribed to among the oldest traces of biological activity known on Earth. These results are of valuable importance since such carbonates are linked to primitive living organisms that can be considered as good analogues for putative Martian life forms. Considering that the microstructures of biogenic carbonate are different from those of abiogenic origin, we investigated the micromorphology of shells, skeletal grains and microbialites at different scale with a scanning electron microscope. The results show that this line of research may provide an alternative and complementary approach to other techniques developed in the past by our group to distinguish biotic from abiotic carbonates. In this paper, we present some results that can be of valuable interest since they demonstrate the utility for a database of images concerning the structures and textures of relevant carbonate minerals. Such data may be useful for the analysis of Martian samples, coming from sample return missions or investigated by future in situ explorations, aimed to characterize the near-subsurface of Mars in search for past or present life.
While a number of site testing campaigns are in progress throughout the world, the dominant efforts seem to be associated with plans for very large telescopes. These plans, improved telescope technology, and the realization that astronomical observations from space will put increasing demands on ground-based observing facilities have given new impetus to site identification and to the optimum utilization of existing sites. A most excellent review of the factors involved in site identification is now available in the Proceedings of the ESO Workshop on Site Testing for Future Large Telescopes, edited by A. Ardeberg and L. Woltjer 1981. These Proceedings and Woolf’s review (1982, Ann. Rev. Astron. Astrophys. 20 367) provide a solid background of current site evaluation factors.
One of the outstanding features of RS CVn-type binaries is the changing shape of the so called “wave-like distortion” or “photometric wave” (PW) and its phase migration on the light curve (LC). Here we present a preliminary analysis of the observations of the following objects: CQ Aur, RU Cnc, VV Mon and SZ Psc. For each system we have derived the amplitude and phase of the PW maximum and its migration rate.
The characteristic optical light curves of RS CVn - and BY Dra-type variables are believed to represent non-uniform distribution of dark spots akin to sunspots which are revealed by rotation. By analogy with the Sun, strong magnetic fields probably underlie this phenomenon, extending upwards into the chromosphere and corona, enhancing the emission from regions that overlie the spots. Previous work on the BY Dra variable AU Mic (Ref.l) did not clarify whether the fluxes from chromospheric and transition region lines were rotationally modulated in the sense that the phase of maximum emission was in register with spot visibility or minimum light. This important question prompted the need for further collaborative IUE, optical and radio work.
This has been a timely conference. Astronomical spectroscopic classification is facing crossroads that make it wise for us to look carefully at where we are now and which way we should go. The on-going explosion in detection techniques for fainter and fainter objects at all wavelengths and the availability of fast analytical procedures are opening up these new roads. It is a tribute to Fr. Patrick Treanor’s vision that we have gathered here to take stock of the current status and to consider the future of spectral classification and it was fitting that we did so while remembering the pioneering work of Fr. Angelo Secchi
The discovery of different ratios of carbon (C-type) to oxygen stars (M type) in the direction of the central regions of our own and the nearest galaxies, the Large and Small Magellanic Clouds, is the result of surveys made by Blanco, Blanco and Hoag (unpublished) who observed Baade's Window near NGC 6522 in the direction of our Galaxy's nuclear bulge and by Blanco, Blanco and McCarthy (in press) who observed selected regions in the center of the Large and Small Magellanic Clouds. We have observed each of these central regions with a combination of a grating and prism set in the converging beam of the prime focus of the CTIO 4 meter telescope (Hoag 1976). We used Eastman IV-N plates hypersensitized with silver nitrate solution; the spectral plates were exposed through a Wratten 89 filter for 60 min. We limited our spectral survey to M type stars later then M5 and to the carbon stars, using the criteria of Nassau and colleagues (1949). Thus far no S type stars have been discerned in central regions of the LMC or SMC at the dispersion used (2300 Å/mm).
In his pioneer study of the RR Lyrae variable stars near NGC 6522, in the relatively unobscured window close to the galactic center (1 = 0.9, b = −3.9), Baade (1963) was limited by the high zenith distance of the galactic center as seen from Palomar, and suggested that southern hemisphere observations would be of value. Subsequent studies of the region have been based on the variables found in Baade's original search. Southern hemisphere plates were taken by Hartwick et al. (1972), and their re-analysis of a sample of Baade's variables showed many periods to be in error. They did not, however, search the plates for new variables. Plaut (1973) re-analyzed all the variables but no search for new variables was done.
The telescope used for identification of X-ray sources at the Cerro Tololo Inter-American Observatory is the Curtis Schmidt Telescope. This telescope is located at Tololo by agreement with the University of Michigan. The field of the telescope is 5° × 5° and its correcting aspheric plate has negligible chromatic aberration over the range 3200 to 10000 Å. This latter feature makes it an ideal instrument for multicolor survey work.
Although white-matter abnormalities have been reported in middle-aged patients with major depressive disorder (MDD), few data are available on treatment-resistant MDD and the influence of relevant variables related to clinical burden of illness is far from being well established.
The present study examined white-matter microstructure in a sample of 52 patients with MDD in different stages (treatment-resistant/chronic MDD, n = 18; remitted-recurrent MDD, n = 15; first-episode MDD, n = 19) and 17 healthy controls, using diffusion tensor imaging with a tract-based spatial statistics approach. Groups were comparable in age and gender distribution, and results were corrected for familywise error (FWE) rate.
Widespread significant reductions of fractional anisotropy (FA) – including the cingulum, corpus callosum, superior and inferior longitudinal fascicule – were evident in treatment-resistant/chronic MDD compared with first-episode MDD and controls (p < 0.05, FWE-corrected). Decreased FA was observed within the ventromedial prefrontal region in treatment-resistant/chronic MDD even when compared with the remitted-recurrent MDD group (p < 0.05, FWE-corrected). Longer duration of illness (β = –0.49, p = 0.04) and higher depression severity (at a trend level: β = –0.26, p = 0.06) predicted lower FA in linear multiple regression analysis at the whole-brain level. The number of previous episodes and severity of symptoms were significant predictors when focused on the ventromedial prefrontal area (β = −0.28, p = 0.04; and β = −0.29, p = 0.03, respectively). Medication effects were controlled for in the analyses and results remained unaltered.
Our findings support the notion that disruptions of white-matter microstructure, particularly in fronto-limbic networks, are associated with resistance to treatment and higher current and past burden of depression.