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There is a long history of exploitation of the South American river turtle Podocnemis expansa. Conservation efforts for this species started in the 1960s but best practices were not established, and population trends and the number of nesting females protected remained unknown. In 2014 we formed a working group to discuss conservation strategies and to compile population data across the species’ range. We analysed the spatial pattern of its abundance in relation to human and natural factors using multiple regression analyses. We found that > 85 conservation programmes are protecting 147,000 nesting females, primarily in Brazil. The top six sites harbour > 100,000 females and should be prioritized for conservation action. Abundance declines with latitude and we found no evidence of human pressure on current turtle abundance patterns. It is presently not possible to estimate the global population trend because the species is not monitored continuously across the Amazon basin. The number of females is increasing at some localities and decreasing at others. However, the current size of the protected population is well below the historical population size estimated from past levels of human consumption, which demonstrates the need for concerted global conservation action. The data and management recommendations compiled here provide the basis for a regional monitoring programme among South American countries.
Quantifying the physical mechanisms responsible for the transport of sediments, nutrients and pollutants in the abyssal sea is a long-standing problem, with internal waves regularly invoked as the relevant mechanism for particle advection near the sea bottom. This study focuses on internal-wave-induced particle transport in the vicinity of (almost) vertical walls. We report a series of laboratory experiments revealing that particles sinking slowly through a monochromatic internal wave beam experience significant horizontal advection. Extending the theoretical analysis by Beckebanze et al. (J. Fluid Mech., vol. 841, 2018, pp. 614–635), we attribute the observed particle advection to a peculiar and previously unrecognized streaming mechanism in the stratified boundary layer originating at the lateral walls. This vertical boundary layer streaming mechanism is most efficient for significantly inclined wave beams, when vertical and horizontal velocity components are of comparable magnitude. We find good agreement between our theoretical prediction and experimental results.
We present a continuous, sediment core-based record of paleohydroclimate spanning ~5800 cal yr BP to recent from Lower Pahranagat Lake (LPAH), a shallow, alkaline lake in southern Nevada. We apply stable isotopes (δ18O and δ13C) from fine-fraction authigenic carbonate, which are sensitive recorders of hydroclimatic variability in this highly evaporative region. Additional geochemical proxies (total organic carbon, C/N, and total inorganic carbon) provide supporting information on paleoecological change in and around the lake. Our data suggest progressively wetter conditions starting at the later part of the middle Holocene and extending into the late Holocene (~5500–3350 cal yr BP) followed by a millennial-scale dry period from ~3150 to 1700 cal yr BP. This latter interval encompasses the ‘Late Holocene dry period’ (LHDP) reported by other investigators, and our data help refine the area affected in this episode. Our data also show evidence for a series of century-scale fluctuations in regional hydroclimate, including wet and dry intervals between 2350 and 1600 cal yr BP, and drier conditions over the past few centuries. Paleohydroclimate trends in the LPAH record show correspondence with those from the central Great Basin to the north, suggesting that both areas were subject to similar climatic forcings.
Three beta-excited X-ray source types (the compound, apposition, and mixture source) have been designed, and the photon spectra compared. Each source in a series was assembled using a single target element with the concentration of pure beta emitter held constant for the series. The apposition source was studied with varying target thicknesses. The compound sources were crystalline precipitates of molybdate and tungstate groups compounded with the nonearrier-free beta emitter. The mixture source consisted of a fine-milled target powder with the beta emitter adsorbed on it. Assay of the X-ray source emission has been done on the Radiation Instrument Development Laboratories (RIDL) lOQ-channel analyzer with a 3-in. Nal detector. Variation in the spectra exists between the source types of a series. Anomalous peaking occurs with the Sr90 MoO4 source emission at 29 key. The compound source, potentially productive, demonstrates poor characteristic spectra.
As of 2015, the percentage of the unemployed who are long-term unemployed remains at levels unseen in the US in over six decades. A well-established literature associates long-term unemployment with a variety of social ills, including poverty, increased risk of physical and mental health problems, and deteriorating emotional well-being. This chapter describes the nature and scope of long-term unemployment in the United States and its impact on individuals and families. It also focuses on the issue of mental health and explores the causal relationship between long-term unemployment and mental health as well as the most promising solutions to the mental health challenges raised by long-term unemployment. The final section of the chapter focuses on the challenges that arise when long-term unemployed workers internalize the stigma of unemployment and blame themselves for their labor market difficulties, and it considers possible causes of and solutions to such self-blame.
Lyndochite from Tura dukas, 35 miles north of Nanyuki, Kenya, agrees closely with the type material from Canada in its chemical analysis, in the distribution of the rare earths, and in X-ray diffraction data for powder after heat treatment. The mineral is compared and contrasted with aeschynite. Uranium-poor euxenite is intimately associated with lyndochite at the type locality.
Since its discovery over thirty-five years ago, lyndochite has remained unrecorded outside its type locality of Lyndoch Township in Ontario, Canada. Its distinctive chemical composition sets it apart from almost all other Ti-rich metamiet niobates and, despite the many analyses that have been made on rare-earth niobate-tantalates, specimens that could have been regarded as similar to or approximating to lyndochite have rarely been mentioned. Its unusual characteristics include high ThO2 (about 10%) and appreciable rare-earth oxides (about 20%) with a lanthanon assemblage showing a peak concentration of Nd (and Ce), rather than any of the heavy lanthanons. The proportions of TiO2 (about 20%) and (Nb,Ta)2O5 (about 40%) are comparable to those in numerous niobate-tantalates, but are only associated with the percentages of ThO2 and Re2O3 mentioned above in some members of the aesehynite-priorite series. The lyndochite now described is chemically very close indeed to the Canadian lyndochite, and both specimens give closely similar X-ray diffraction patterns (after suitable heat treatment) which are distinct from those of any other metamict mineral.
We present first results from a coordinated multiwavelength study of the neutron star low-mass X-ray binary EXO 0748 676. Fast UV, X-ray, and optical data were obtained including both spectral and timing information. We discuss how this study allows us to probe the temperature distribution within the binary and hence the geometry and efficiency of X-ray irradiation.
Older care home residents are excluded from the sexual imaginary. Based on a consultative study involving interviews with three residents, three female spouses of residents and two focus groups of care home staff (N = 16), making an overall sample of 22 study participants, we address the neglected subject of older residents' sexuality and intimacy needs. Using thematic analysis, we highlight how residents’ and spouses’ accounts of sexuality and intimacy can reflect an ageist erotophobia occurring within conditions of panoptical control that help construct residents as post-sexual. However, not all accounts contributed to making older residents’ sexuality appear invisible or pathological. Some stories indicated recuperation of identities and the normalisation of relationships with radically changed individuals, e.g. because of a dementia. We also examine care home staff accounts of the discursive obstacles that frustrate meeting residents’ needs connected with sexuality and intimacy. Simultaneously, we explore staffs’ creative responses to dilemmas which indicate approaches to sexuality driven more by observed needs than erotophobic anxiety and governance, as well as panoptical surveillance.
In traditional electron/ion laboratory plasmas, the system size
is much larger than both the plasma skin depth
and the Debye length
. In current and planned efforts to create electron/positron plasmas in the laboratory, this is not necessarily the case. A low-temperature, low-density system may have
; a high-density, thermally relativistic system may have
. Here we consider the question of what plasma physics phenomena are accessible (and/or diagnostically exploitable) in these different regimes and how this depends on magnetization. While particularly relevant to ongoing pair plasma creation experiments, the transition from single-particle behaviour to collective, ‘plasma’ effects – and how the criterion for that threshold is different for different phenomena – is an important but often neglected topic in electron/ion systems as well.
Depression is a significant problem and it is vital to understand its underlying causes and related policy implications. Neighborhood characteristics are implicated in depression but the nature of this association is unclear. Unobserved or unmeasured factors may confound the relationship. This study addresses confounding in a twin study investigating neighborhood-level effects on depression controlling for genetics, common environment, and gene×environment (G × E) interactions.
Data on neighborhood deprivation and depression were gathered from 3155 monozygotic twin pairs and 1275 dizygotic pairs (65.7% female) between 2006 and 2013. The variance for both depression and neighborhood deprivation was decomposed into three components: additive genetic variance (A); shared environmental variance (C); and non-shared environmental variance (E). Depression was then regressed on neighborhood deprivation to test the direct association and whether that association was confounded. We also tested for a G × E interaction in which the heritability of depression was modified by the level of neighborhood deprivation.
Depression and neighborhood deprivation showed evidence of significant A (21.8% and 15.9%, respectively) and C (13.9% and 32.7%, respectively) variance. Depression increased with increasing neighborhood deprivation across all twins (p = 0.009), but this regression was not significant after controlling for A and C variance common to both phenotypes (p = 0.615). The G × E model showed genetic influences on depression increasing with increasing neighborhood deprivation (p < 0.001).
Neighborhood deprivation is an important contributor to depression via increasing the genetic risk. Modifiable pathways that link neighborhoods to depression have been proposed and should serve as targets for intervention and research.
Chamorro-Premuzic, Winsborough, Sherman, and Hogan (2016) note that new talent signals recently adopted by organizations are related to older selection and assessment methods. Drawing this connection between old and new technologies is helpful; however, viewing new technology as either shiny new objects or a brave new world creates a false dichotomy. Recent technology-enhanced human resources (HR) processes like the widespread use of gamified practices and video-recorded interviewing are not just fads or the beginning of a transformation in HR but rather natural evolutions of methods that differ across specific dimensions that can be identified and measured. It is important to view these recent advances as extensions of the existing methods. That is, we need to focus on how these new methods are different and not on that they are different.
Eddington is a space mission for extrasolar planet finding and for asteroseismic observations. It has been selected by ESA as an F2/F3 reserve mission with a potential implementation in 2008-13. Here we describe Eddington's capabilities to detect extrasolar planets, with an emphasis on the detection of habitable planets. Simulations covering the instrumental capabilities of Eddington and the stellar distributions in potential target fields lead to predictions of about 10,000 planets of all sizes and temperatures, and a few tens of terrestrial planets that are potentially habitable. Implications of Eddington for future larger scale missions are briefly discussed.
We present the results of a study of the evolution of the gas and dust in disks around T Tauri, Herbig Ae and Vega-like stars. We observed the two lowest rotational lines of H2 with the ISO-SWS as well as 12CO 3–2 and 13CO 3–2 with the JCMT, and CO 6–5 with the CSO. The H2 lines trace the warm (∽ 100 K) inner region whereas the CO lines probe the colder outer disks. Substantial amounts of H2 have been detected toward T Tauri and Herbig Ae stars, and, surprisingly, also around three Vega-like objects (49 Cet, HD 135344 and β Pictoris). In contrast with previous conclusions derived from CO data, a significant mass of warm gas is found to persist up to ages of several tens of Myrs, suggesting that slow formation of gas-rich giant planets is possible.
At the Paris meeting in 1935 the following resolutions of Commission 3 were adopted by the Union:
1.Que la liste préliminaire de notations préparée par le Président de la Commission soit, après certaines modifications, imprimée dans les Transactions de l’Union à titre de liste recommandée provisoirement, et que les astronomes intéressés à la question soient invités a adresser au Président de la Commission les changements qu’ils y suggéreraient.
2.Que l’Union donne son approbation à la publication d’un complément mentionnant les changements et additions à la liste des Observatoires et des Astronomes publiée en 1931, sous les auspices de l’Union, par l’Observatoire Royal d’Uccle.
3.Que l’Union consacre, si possible, une somme n’excédant pas cinq cents francs or, à aider la publication de ce complément.
3.The provisional list of notations was printed, as an appendix to the report of Commission 3, Trans. I.A.U. 5, 18, 1935. A number of astronomers communicated to the President of the Commission suggestions of changes. On the basis of these suggestions a corrected list of notations was prepared.
3.Reprints of this list were circulated to the various observatories and suggestions of changes invited. In response to this a number of suggestions were received.
At the Cambridge meeting in 1932 the following resolutions of Commission 3 were adopted by the Union:
1.Que l’équinoxe de 1900.0 soit adopté pour tous catalogues qui ne sont pas catalogues de précision et que quand on désirera plus tard de changer l’équinoxe celui de 2000.0 soit adopté.
2.Que les abréviations (à 4 lettres) des noms des astérismes qui se trouvent dans le Catalogue of Bright Stars (Schlesinger) soient approuvées à l’exception de cinq astérismes qui seront représentés par Arie, Cane, Dlph, Tria, Tr Au (v. Trans. LA.U. 4, 221, 1932).
3.Que la Commission favorise l’établissement d’une notation uniforme dans l’astronomie, à moins qu’il n’y ait pas de conflit avec de notations semblables dans les sciences alliées.
With the publication of the volume Délimitation Scientifique des Constellations and the Atlas Céleste, and the adoption of standard sets of three-letter abbreviations (Rome 1922) and four-letter abbreviations (Cambridge 1932) for the constellations, important work was brought to a close. The main task now before Commission 3 appears to be the working out and publication of a set of notations covering the whole field of astronomy.
We have detected He I absorption from the companion star to X1822–371 and find a lower limit to its K–velocity of 230±50km s−1. We interpret the He I as arising on the X-ray heated inner face of the companion star.
We have discovered hard and soft X-ray emission from W Puppis, the last of the four classical AM Her stars to be detected in X-rays. The orbital light curves in both soft and hard X-rays are in excellent agreement with the mean optical light curve, indicating that essentially all of the accretion luminosity originates from a very small region at the white dwarf’s magnetic pole. An X-ray dip occurs once per binary period, when the magnetic pole lies closest to our line of sight, and is probably due to absorption. The X-ray data and optical spectroscopy constrain fairly well the geometry of the system, dictating an inclina-tion angle i < 70º and a mass for the white dwarf in excess of 1.1 Mʘ. X-ray and UV observations constrain the temperature of the soft X-ray component to lie in the range 20–45 eV, while the hard X-ray component has a temperature in excess of 6 keV. The observed flux of soft X-rays is much larger than that of hard X-rays. However, when the energy band-passes of the observations are taken into account, the ratio of the soft and hard X-ray luminosities Ls/Lh = 0.5-50. The ratio is unity for Tbb = 30 eV and Tbr = 50 keV; ifc is smaller if Tbb and/or Tbr are larger and is larger in the opposite case. These results, taken together with those for AM Her using the Einstein OGS, suggest that the famous “soft X-ray problem” in the AM Her stars may have gone away.
Sexuality and intimacy in care homes for older people are overshadowed by concern with prolonging physical and/or psychological autonomy. When sexuality and intimacy have been addressed in scholarship, this can reflect a sexological focus concerned with how to continue sexual activity with reduced capacity. We review the (Anglophone) academic and practitioner literatures bearing on sexuality and intimacy in relation to older care home residents (though much of this applies to older people generally). We highlight how ageism (or ageist erotophobia), which defines older people as post-sexual, restricts opportunities for the expression of sexuality and intimacy. In doing so, we draw attention to more critical writing that recognises constraints on sexuality and intimacy and indicates solutions to some of the problems identified. We also highlight problems faced by lesbian, gay, bisexual and trans (LGB&T) residents who are doubly excluded from sexual/intimate citizenship because of ageism combined with the heterosexual assumption. Older LGB&T residents/individuals can feel obliged to deny or disguise their identity. We conclude by outlining an agenda for research based on more sociologically informed practitioner-led work.
Ca supplements are used for bone health; however, they have been associated with increased cardiovascular risk, which may relate to their acute effects on serum Ca concentrations. Microcrystalline hydroxyapatite (MCH) could affect serum Ca concentrations less than conventional Ca supplements, but its effects on bone turnover are unclear. In the present study, we compared the acute and 3-month effects of MCH with conventional Ca supplements on concentrations of serum Ca, phosphate, parathyroid hormone and bone turnover markers. We randomised 100 women (mean age 71 years) to 1 g/d of Ca as citrate or carbonate (citrate–carbonate), one of two MCH preparations, or a placebo. Blood was sampled for 8 h after the first dose, and after 3 months of daily supplementation. To determine whether the acute effects changed over time, eight participants assigned to the citrate dose repeated 8 h of blood sampling at 3 months. There were no differences between the citrate and carbonate groups, or between the two MCH groups, so their results were pooled. The citrate–carbonate dose increased ionised and total Ca concentrations for up to 8 h, and this was not diminished after 3 months. MCH increased ionised Ca concentrations less than the citrate–carbonate dose; however, it raised the concentrations of phosphate and the Ca–phosphate product. The citrate–carbonate and MCH doses produced comparable decreases in bone resorption (measured as serum C-telopeptide (CTX)) over 8 h and bone turnover (CTX and procollagen type-I N-terminal propeptide) at 3 months. These findings suggest that Ca preparations, in general, produce repeated sustained increases in serum Ca concentrations after ingestion of each dose and that Ca supplements with smaller effects on serum Ca concentrations may have equivalent efficacy in suppressing bone turnover.