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The purpose of this article is to discuss the challenges and opportunities for integrating archaeological information in landscape-scale conservation design while aligning archaeological practice with design and planning focused on cultural resources. Targeting this opportunity begins with statewide archaeological databases. Here, we compare the structure and content of Pennsylvania's and Florida's statewide archaeological databases, identifying opportunities for leveraging these data in landscape conservation design and planning. The research discussed here was part of a broader project, which was working through the lens of Landscape Conservation Cooperatives in order to develop processes for integrating broadly conceived cultural resources with natural resources as part of multistate or regional landscape conservation design efforts. Landscape Conservation Cooperatives offer new ways to think about archaeological information in practice and potentially new ways for archaeology to contribute to design and planning. Statewide archaeological databases, in particular, offer transformative potential for integrating cultural resource priorities in landscape conservation design. Targeted coordination across state boundaries along with the development of accessible derivative databases are two priorities to advance their utility.
Restoration in Mediterranean-climate grasslands is strongly impeded by lack of native propagules and competition with exotic grasses and forbs. We report on a study testing several methods for exotic plant control combined with planting native grasses to restore prairies in former agricultural land in coastal California. Specifically we compared tarping (shading out recently germinated seedlings with black plastic) once, tarping twice, topsoil removal, herbicide (glyphosate), and a control treatment in factorial combinations with or without wood mulch. Into each treatment we planted three native grass species (Elymus glaucus, Hordeum brachyantherum, and Stipa pulchra) and monitored plant survival and cover for three growing seasons. Survival of native grass species was high in all treatments, but was slightly lower in unmulched soil removal and control treatments in the first 2 yr. Mulching, tarping, and herbicide were all effective in reducing exotic grass cover and enhancing native grass cover for the first 2 yr, but by the third growing season cover of the plant guilds and bare ground had mostly converged, primarily because of the declining effects of the initial treatments. Mulching and tarping were both considerably more expensive than herbicide treatment. Topsoil removal was less effective in increasing native grass cover likely because soil removal altered the surface hydrology in this system. Our results show that several treatments were effective in enhancing native grass establishment, but that longer term monitoring is needed to evaluate the efficacy of restoration efforts. The most appropriate approach to controlling exotics to restore specific grassland sites will depend not only on the effectiveness, but also on relative costs and site constraints.
Advances made in the understanding of the molecular biology of the cardiac valves have been truly spectacular. Not all of those investigating these aspects, however, have an appropriate understanding of the underlying anatomy. Partly, this reflects problems in describing the components of the various valves, a difficulty also emphasised by surgeons who repair or replace the valves. In this review, we describe briefly the overall anatomy of the cardiac valves, pointing to their similarities and differences. We then suggest that uniform terms can be developed to account for the components of the valves, treating them as complexes that guard the atrioventricular and ventriculo-arterial junctions. The atrioventricular valvar complex is made up of an annulus, leaflets, tendinous cords, and papillary muscles. The tension apparatus is required to hold the leaflets together against the force of ventricular systole. The ventriculo-arterial complex is also based on the leaflets, but supported within the valvar sinuses, and limited distally by the sinutubular junction. It is the semilunar nature of the leaflets that underscores their snug closure during ventricular diastole. The complexes thus defined can be separated to produce paired valves in the normal arrangement, or to produce common valves in the congenitally malformed hearts. Knowledge of development now permits accurate inferences to be made regarding the origin of the various components, and their relevance to valvar disease. The valvar leaflets are developed from the endocardial cushions formed in the atrioventricular canal and the outflow tract by a process of endothelial-to-mesenchymal transformation. The papillary muscles of the atrioventricular valves are then derived from the trabecular layer of the developing ventricular walls, whereas the sinuses of the ventriculo-arterial valves are formed by additional growth of the non-myocardial tissues, concomitant with excavation of the outflow cushions to form the leaflets.
Extensive areas in the upper Midwest have been invaded by spotted knapweed, and effective management strategies are required to reestablish native plant communities. We examined effects of mowing, mowing plus clopyralid, or mowing plus glyphosate in factorial combination with hand pulling and burning on knapweed abundances on a knapweed-infested site in western Michigan. We applied mowing and herbicide treatments in summer 2008, and seeded all plots with native grasses and forbs in spring 2009. We conducted the knapweed pulling treatment from 2009 to 2012 in July. The prescribed burn was conducted in April 2012. By 2012, hand pulling reduced adult knapweed densities to 0.57 ± 0.12 m−2 (0.053 ± 0.011 ft−2) (mean ± SE), which was 5.8% of nonpulled treatments, juvenile densities to 0.29 ± 0.07 m−2 (2.1% of nonpulled treatments), and seedling densities to 0.07 ± 0.06 m−2 (2.6% of nonpulled treatments). After 3 yr, hand pulling reduced seed bank densities to 68 ± 26 m−2 as compared to 524 ± 254 m−2 in nonpulled treatments and 369 ± 66 m−2 in adjacent untreated areas of the study site. Without hand pulling, effects of mowing or mowing plus glyphosate were short-lived and allowed knapweed to rapidly resurge. In comparison, although a single mowing plus clopyralid treatment maintained significantly reduced densities of knapweed for 4 yr, by 2012 knapweed biomass in the nonpulled clopyralid treatment was approximately 60% of that in the other nonpulled treatments. Burning had minimal impacts on knapweed densities regardless of treatment combination, probably as a result of low fire intensity. Results demonstrated that persistent hand pulling used as a follow-up to single mowing or mowing plus herbicide treatments can be an effective practice for treating isolated spotted knapweed infestations or for removing small numbers of knapweed that survive herbicide applications.
Significant new opportunities for astrophysics and cosmology have been identified at low radio frequencies. The Murchison Widefield Array is the first telescope in the southern hemisphere designed specifically to explore the low-frequency astronomical sky between 80 and 300 MHz with arcminute angular resolution and high survey efficiency. The telescope will enable new advances along four key science themes, including searching for redshifted 21-cm emission from the EoR in the early Universe; Galactic and extragalactic all-sky southern hemisphere surveys; time-domain astrophysics; and solar, heliospheric, and ionospheric science and space weather. The Murchison Widefield Array is located in Western Australia at the site of the planned Square Kilometre Array (SKA) low-band telescope and is the only low-frequency SKA precursor facility. In this paper, we review the performance properties of the Murchison Widefield Array and describe its primary scientific objectives.
High-quality data from appropriate archives are needed for the continuing improvement of radiocarbon calibration curves. We discuss here the basic assumptions behind 14C dating that necessitate calibration and the relative strengths and weaknesses of archives from which calibration data are obtained. We also highlight the procedures, problems, and uncertainties involved in determining atmospheric and surface ocean 14C/12C in these archives, including a discussion of the various methods used to derive an independent absolute timescale and uncertainty. The types of data required for the current IntCal database and calibration curve model are tabulated with examples.
The Kepler Mission successfully launched March 6, 2009, beginning its 3.5-year mission to determine the frequency of Earth-size planets in the habitable zones of late-type stars. The brightnesses of over 100,000 stars are currently being monitored for transit events with an expected differential photometric precision of 20 ppm at V=12 for a 6.5-hour transit. The same targets will be observed continuously over the mission duration in order to broaden the detection space to orbital periods comparable to that of Earth. This paper provides an overview of the selection and prioritization criteria used to choose the stars that Kepler is observing from the > 4.5 million objects in the 100 square degree field of view. The characteristics of the Kepler targets are described as well as the implications for detectability of planets in the habitable zone smaller than 2R⊕.
To assess the folate and vitamin B12 status of a group of Vietnamese women of reproductive age and to estimate the rate of neural tube defects (NTD) based on red blood cell (RBC) folate concentrations.
Design and subjects
A representative sample of non-pregnant women (15–49 years) living in Hanoi City (n 244) and Hai Duong Province (n 245).
RBC folate, plasma vitamin B12 and plasma holo-transcobalamin (holoTC), a sensitive indicator of vitamin B12 status.
Mean (95 % CI) concentrations of RBC folate, plasma B12 and plasma holoTC were 856 (837, 876) nmol/l, 494 (475, 513) pmol/l and 78 (74, 82) pmol/l, respectively. Only 3 % and 4 % of women had plasma B12 and holoTC concentrations indicative of deficiency. No woman had an RBC folate concentration indicative of deficiency (<317 nmol/l). Only 47 % of women had an RBC folate concentration ≥905 nmol/l. Accordingly, we predict the NTD rate in these regions of Vietnam to be 14·7 (14·2, 15·1) per 10 000 pregnancies.
There was no evidence of folate and vitamin B12 deficiency among this population of Vietnamese women. However, suboptimal folate status may be placing three out of five women at increased risk of NTD. Reductions in NTD rates are still possible and women would benefit from additional folic acid during the periconceptional period from either supplements or fortified foods.
In introducing this Special Issue on Social Capital and Health, this article tracks the popularization of the term ‘social capital’ and sheds light on the controversy surrounding the term and its definitions. It sets out four mechanisms that link social capital with health: making information available to community members, impacting social norms, enhancing the health care services and their accessibility in a community, and offering psychosocial support networks. Approaches to the measurement of social capital include the Social Capital Community Benchmark Survey (SCCBS) developed by Robert Putnam, and the Petris Social Capital Index (PSCI), which looks at community voluntary organizations using public data available for the entire United States. The article defines community social capital (CSC) as the extent and density of trust, cooperation, and associational links and activity within a given population. Four articles on CSC are introduced in two categories: those that address behaviors – particularly utilization of health services and use of tobacco, alcohol, and drugs; and those that look at links between social capital and physical or mental health. Policy implications include: funding and/or tax subsidies that would support the creation of social capital; laws and regulations; and generation of enthusiasm among communities and leaders to develop social capital. The next steps in the research programme are to continue testing the mechanisms; to look for natural experiments; and to find better public policies to foster social capital.
Timothy M. Brown, High Altitude Observatory, National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80307, USA,
Roi Alonso, Instituto de Astrofisica de Canarias, La Laguna, Tenerife, SPAIN,
Michael Knölker, High Altitude Observatory, National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80307, USA,
Heike Rauer, Institute of Planetary Research, DLR, Rutherfordstrasse 2, 12489 Berlin, Germany,
Wolfgang Schmidt, Kiepenheuer Institut für Sonnenphysik, Freiburg, Germany
Mario Livio, Space Telescope Science Institute, Baltimore,Kailash Sahu, Space Telescope Science Institute, Baltimore,Jeff Valenti, Space Telescope Science Institute, Baltimore
The extrasolar planets known to date have masses and orbital periods spanning a large range. Those for which we have definite knowledge about physical composition have much more restricted properties: they are either transiting planets with near-Jovian masses and orbital periods of a few days, or (as in a couple of recent discoveries) they are distant low-mass companions to objects that are themselves low-mass and young. Here we will concentrate on the former group of objects, and try to summarize what is known and conjectured concerning their atmospheres based on observations of their transits. By way of motivation and illustration of the ultimate possibilities available to transit observations, we begin by discussing recent observations of the transit of Venus in June 2004.
The SWEEPS (Sagittarius Window Eclipsing Extrasolar Planet Search) program was aimed at detecting planets around stars in the Galactic bulge, not only to determine their physical properties, but also to determine whether the properties of planets found in the solar neighborhood, such as their frequency and the metallicity dependence, also hold for the planets in the Galactic bulge. We used the Hubble Space Telescope to monitor 180,000 F, G, K, and M dwarfs in the Galactic bulge continuously for 7 days in order to look for transiting planets. We discovered 16 candidate transiting extrasolar planets with periods of 0.6 to 4.2 days, including a possible new class of ultra-short period planets (USPPs) with P < 1 day. The facts that (i) the coverage in the monitoring program is continuous, (ii) most of the stars are at a known distance (in the Galctic bulge), (iii) monitoring was carried out in 2 passbands, and (iv) the images have high spatial resolution, were crucial in minimizing and estimating the false positive rates. We estimate that at least 45% of the candidates are genuine planets. Radial velocity observations of the two brightest host stars further support the planetary nature of the transiting companions. These results suggest that the planet frequency in the Galactic bulge is similar to that in the solar neighborhood. They also suggest that higher metallicity favors planet formation even in the Galactic bulge. The USPPs occur only around low-mass stars which may suggest that close-in planets around higher-mass stars are irradiately evaporated, or that planets are able to migrate to and survive in close-in orbits only around such old and low-mass stars.