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The mammal family Tenrecidae (Afrotheria: Afrosoricida) is endemic to Madagascar. Here we present the conservation priorities for the 31 species of tenrec that were assessed or reassessed in 2015–2016 for the IUCN Red List of Threatened Species. Six species (19.4%) were found to be threatened (4 Vulnerable, 2 Endangered) and one species was categorized as Data Deficient. The primary threat to tenrecs is habitat loss, mostly as a result of slash-and-burn agriculture, but some species are also threatened by hunting and incidental capture in fishing traps. In the longer term, climate change is expected to alter tenrec habitats and ranges. However, the lack of data for most tenrecs on population size, ecology and distribution, together with frequent changes in taxonomy (with many cryptic species being discovered based on genetic analyses) and the poorly understood impact of bushmeat hunting on spiny species (Tenrecinae), hinders conservation planning. Priority conservation actions are presented for Madagascar's tenrecs for the first time since 1990 and focus on conserving forest habitat (especially through improved management of protected areas) and filling essential knowledge gaps. Tenrec research, monitoring and conservation should be integrated into broader sustainable development objectives and programmes targeting higher profile species, such as lemurs, if we are to see an improvement in the conservation status of tenrecs in the near future.
Experiments on the National Ignition Facility show that multi-dimensional effects currently dominate the implosion performance. Low mode implosion symmetry and hydrodynamic instabilities seeded by capsule mounting features appear to be two key limiting factors for implosion performance. One reason these factors have a large impact on the performance of inertial confinement fusion implosions is the high convergence required to achieve high fusion gains. To tackle these problems, a predictable implosion platform is needed meaning experiments must trade-off high gain for performance. LANL has adopted three main approaches to develop a one-dimensional (1D) implosion platform where 1D means measured yield over the 1D clean calculation. A high adiabat, low convergence platform is being developed using beryllium capsules enabling larger case-to-capsule ratios to improve symmetry. The second approach is liquid fuel layers using wetted foam targets. With liquid fuel layers, the implosion convergence can be controlled via the initial vapor pressure set by the target fielding temperature. The last method is double shell targets. For double shells, the smaller inner shell houses the DT fuel and the convergence of this cavity is relatively small compared to hot spot ignition. However, double shell targets have a different set of trade-off versus advantages. Details for each of these approaches are described.
This list reports certain 14C measurements completed by December 1979; other projects completed by this time will be reported later. Age calculations are based on 14C half-life of 5568 yr and modern standard of 95% NBS oxalic acid, supplemented by tree rings of pre-industrial wood from a log cut in the 1850's (Tx-540; R, 1970, v 12, p 249). Deviations reported are based on counting statistics of sample, background and modern, and are ± 1σ, except that when sample count approaches either modern or background, 2σ limits are reported. Unless noted, 12C/13C measurements were not made and results are not corrected for 13C fractionation (assumed ratio = −25‰ WRT PDB). Our laboratory uses liquid scintillation counting of benzene, with Li2C2 and vanadium-activated catalyst in preparation; chemical yields range between 95% and 99%. Three counters are employed; a Packard Tri-Carb Model 3002 and 2 Beckman LS230 spectrometers obtained through a grant from the National Science Foundation.
We analyze residential architecture and domestic artifacts as expressions of wealth, prestige, and social class at three Aztec-period settlements in Morelos, Mexico: Capilco, Cuexcomate, and Yautepec. House size, as expressed in both floor area and construction volume, shows a strongly bimodal distribution that we interpret as marking elite and commoner residences. We test this interpretation with two artifactual indices of household wealth. One is designed to maximize the elite-commoner distinction in each setting, but is not directly comparable among contexts. The other is a simpler generic wealth index that can be compared among sites and across time. We also consider variability within the commoner class in house size and artifact inventories. While some degree of variation is present, the extent of variation is minor in comparison to the level of elite-commoner differences.
The new Extreme Ultraviolet Explorer (EUVE) Public Right Angle Program (RAP) offers the opportunity for researchers to obtain observations with the EUVE imaging telescopes, oriented at right angles to the EUVE spectrometer used for the NASA Guest Observer Program. Scientists may submit proposals electronically through the World Wide Web or e-mail using a template form to list specific targets and present the scientific motivation for the work. The RAP electronic proposal process is streamlined from proposal submission through data delivery and is a prototype for a system to be used for all guest observers during the EUVE extended mission starting in February, 1996.
The Wisconsin Plasma Astrophysics Laboratory (WiPAL) is a flexible user facility designed to study a range of astrophysically relevant plasma processes as well as novel geometries that mimic astrophysical systems. A multi-cusp magnetic bucket constructed from strong samarium cobalt permanent magnets now confines a
, fully ionized, magnetic-field-free plasma in a spherical geometry. Plasma parameters of
provide an ideal testbed for a range of astrophysical experiments, including self-exciting dynamos, collisionless magnetic reconnection, jet stability, stellar winds and more. This article describes the capabilities of WiPAL, along with several experiments, in both operating and planning stages, that illustrate the range of possibilities for future users.
This paper contributes to research on defined contribution (DC) retirement plans by examining how financial knowledge and demographic factors influenced Chile's pension holders' choice between a default life-cycle retirement plan and active management. About one third of Chileans held default funds in 2009; younger people, men, people with lower incomes, and people with low financial knowledge were more likely to choose the default. For active investors, we examined what variables influenced their choice. Nearly three quarters of active investors chose more risky funds that the defaults for their age group. However, risk taking tended to decrease with age and to increase with income, financial knowledge and risk tolerance.
The purpose of this study was to determine whether five subcomponents of children's externalizing behavior showed distinctive patterns of long-term growth and predictive correlates. We examined growth in teachers' ratings of overt aggression, covert aggression, oppositional defiance, impulsivity/inattention, and emotion dysregulation across three developmental periods spanning kindergarten through Grade 8 (ages 5–13 years). We also determined whether three salient background characteristics, family socioeconomic status, child ethnicity, and child gender, differentially predicted growth in discrete categories of child externalizing symptoms across development. Participants were 543 kindergarten-age children (52% male, 81% European American, 17% African American) whose problem behaviors were rated by teachers each successive year of development through Grade 8. Latent growth curve analyses were performed for each component scale, contrasting with overall externalizing, in a piecewise fashion encompassing three developmental periods: kindergarten–Grade 2, Grades 3–5, and Grades 6–8. We found that most subconstructs of externalizing behavior increased significantly across the early school age period relative to middle childhood and early adolescence. However, overt aggression did not show early positive growth, and emotion dysregulation significantly increased across middle childhood. Advantages of using subscales were most clear in relation to illustrating different growth functions between the discrete developmental periods. Moreover, growth in some discrete subcomponents was differentially associated with variations in family socioeconomic status and ethnicity. Our findings strongly affirmed the necessity of adopting a developmental approach to the analysis of growth in children's externalizing behavior and provided unique data concerning similarities and differences in growth between subconstructs of child and adolescent externalizing behavior.
Kochia is a troublesome weed throughout the western United States. Although
glyphosate effectively controls kochia, poor control was observed in several
no-till fields in Kansas. The objectives of this research were to evaluate
kochia populations response to glyphosate and examine the mechanism that
causes differential response to glyphosate. Glyphosate was applied at 0, 54,
109, 218, 435, 870, 1305, 1740, 3480, and 5220 g ae ha−1 on 10
kochia populations. In general, kochia populations differed in their
response to glyphosate. At 21 d after treatment, injury from glyphosate
applied at 870 g ha−1 range from 4 to 91%. In addition,
glyphosate rate required to cause 50% visible injury (GR50)
ranged from 470 to 2149 g ha−1. Differences in glyphosate
absorption and translocation and kochia mineral content were not sufficient
to explain differential kochia response to glyphosate.