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Semi-diurnal and diurnal tidal dissipation from TOPEX/Poseidon altimetry
Get PDFTidal energy dissipation is estimated for eight semi‐diurnal and diurnal constituents using a global inverse solution constrained by TOPEX/Poseidon altimeter data. Very similar spatial patterns are obtained for all semi‐diurnal constituents, with about one third of the total dissipation occurring in the deep ocean over rough topography. Maps for diurnal constituents are also similar amongst themselves, but quite different from the semi‐diurnal results. For diurnals a smaller fraction of dissipation, roughly 10%, occurs in the deep ocean. Much of the difference can be explained by the very different spatial pattern of diurnal and semi‐diurnal tidal currents. The lack of free internal waves at frequencies poleward of 30° at diurnal frequencies also probably plays a role, limiting the effectiveness of baroclinic conversion as an energy sink for barotropic diurnal tides
HystadPerryPHHSResidentialGreennessBirth_SupplementalMaterial.pdf
No full textBACKGROUND: Half the world’s population lives in urban areas. It is therefore important to identify
characteristics of the built environment that are beneficial to human health. Urban greenness
has been associated with improvements in a diverse range of health conditions, including birth
outcomes; however, few studies have attempted to distinguish potential effects of greenness from
those of other spatially correlated exposures related to the built environment.
OBJECTIVES: We aimed to investigate associations between residential greenness and birth outcomes
and evaluate the influence of spatially correlated built environment factors on these associations.
METHODS: We examined associations between residential greenness [measured using satellite-derived
Normalized Difference Vegetation Index (NDVI) within 100 m of study participants’
homes] and birth outcomes in a cohort of 64,705 singleton births (from 1999–2002) in Vancouver,
British Columbia, Canada. We also evaluated associations after adjusting for spatially correlated
built environmental factors that may influence birth outcomes, including exposure to air pollution
and noise, neighborhood walkability, and distance to the nearest park.
RESULTS: An interquartile increase in greenness (0.1 in residential NDVI) was associated with
higher term birth weight (20.6 g; 95% CI: 16.5, 24.7) and decreases in the likelihood of small
for gestational age, very preterm (< 30 weeks), and moderately preterm (30–36 weeks) birth.
Associations were robust to adjustment for air pollution and noise exposures, neighborhood walkability,
and park proximity.
CONCLUSIONS: Increased residential greenness was associated with beneficial birth outcomes in this
population-based cohort. These associations did not change after adjusting for other spatially correlated
built environment factors, suggesting that alternative pathways (e.g., psychosocial and psychological
mechanisms) may underlie associations between residential greenness and birth outcomes
Context, Provenance and Technology of a Western Stemmed Tradition Artifact Cache from the Cooper's Ferry Site, Idaho
Get PDFSpanish Abstract:
El descubrimiento de un depósito de artefactos conteniendo puntas de proyectil en la
Tradición de Tallo Occidental (Western Stemmed Tradition) en una fosa claramente
definida, en el sitio de Cooper’s Ferry, ofrece una perspectiva única sobre la tecnología
lítica temprana y organización logística en el Occidente de América del Norte. La
descripción y el análisis de este depósito revela nuevas manifestaciones, incluyendo: el
uso de un cumulo rocoso que cubrió la superficie de la fosa; algunos de los artefactos
fueron hechos de silicatos criptocristalinos que se encuentran a 16 km de distancia;
análisis de los desechos de talla, incluyendo las medidas basadas en agregados y sus
atributos, identificaron dos distintas etapas de reducción lítica presentes en el acopio.
Nuevas fechas por radiocarbono indican que este depósito probablemente no
corresponde al Holoceno temprano en antigüedad y bien puede datar a fechas por
radiocarbono de entre 11,370-11,410 años AP. A diferencia de depósitos Clovis, el de
la fosa A2 en Cooper’s Ferry, parece ser un conjunto de herramientas de uso general
que probablemente fue colocado en el sitio para su uso a futuro. Si las fechas 11,370-
11,410 AP datan la creación del depósito en la fosa A2, entonces los autores
probablemente no fueron pioneros en las bajas inmediaciones del cañón del río Salmón
(Salmon River canyon), pero poseían un conocimiento particular acerca del paisaje y
fuentes de materia primas locales; estos patrones sugieren una mayor antigüedad para
los grupos recolectores de la Tradición de Tallo Occidental.The discovery of an artifact cache containing Western Stemmed Tradition projectile
points in a clearly defined pit feature at the Cooper’s Ferry site offers a unique
perspective on early lithic technology and logistical organization in western North
America. A description and analysis of the cache feature reveals several new insights,
including: a rocky cairn capped the surface of the pit feature; some of the artifacts were
made from cryptocrystalline silicates found 16 km away; debitage analysis, including
aggregate and attribute based measures, identified two distinct lithic reduction stages
present in the cache; new radiocarbon assays suggest that the cache is probably not
early Holocene in age and may date to associated radiocarbon age estimates of
11,370-11,410 B.P. Unlike Clovis caches, the Pit Feature A2 cache at Cooper’s Ferry
appears to be a generalized toolkit that was probably placed at the site for future use.
If the 11,370-11,410 B.P. assays date the creation of the Pit Feature A2 cache, then its
creators were probably not pioneers in the lower Salmon River canyon but possessed
local knowledge about the landscape and raw material sources; these patterns suggest
greater time depth for Western Stemmed Tradition foragers
WallaceReoccupancyBreedingTerritories.PDF
No full textGrassland and shrubland birds are declining globally due in part to anthropogenic habitat modification. Because population performance of these species is also influenced by non-anthropogenic factors, it is important to incorporate all relevant ecological drivers into demographic models. We used design-based sampling and occupancy models to test relationships of environmental factors that influence raptor demographics with re-occupancy of breeding territories by ferruginous hawks (Buteo regalis) across Wyoming, USA, 2011-2013. We also tested correlations of territory re-occupancy with oil and gas infrastructure-a leading cause of habitat modification throughout the range of this species of conservation concern. Probability of re-occupancy was not related to any covariates we investigated in 2011, had a strong negative relationship with cover of sagebrush (Artemisia spp.) in 2012, was slightly higher for territories with artificial platforms than other nest substrates in 2013, and had a positive relationship with abundance of ground squirrels (Urocitellus spp.) that was strong in 2012 and weak in 2013. Associations with roads were weak and varied by year, road-type, and scale: in 2012, re-occupancy probability had a weak positive correlation with density of roads not associated with oil and gas fields at the territory-scale; however, in 2013 re-occupancy had a very weak negative correlation with density of oil and gas field roads near nest sites (≤ 500 m). Although our results indicate re-occupancy of breeding territories by ferruginous hawks was compatible with densities of anthropogenic infrastructure in our study area, the lack of relationships between oil and gas well density and territory re-occupancy may have occurred because pre-treatment data were unavailable. We used probabilistic sampling at a broad spatial extent, methods to account for imperfect detection, and conducted extensive prey sampling; nonetheless, future research using before-after-control-impact designs is needed to fully assess impacts of oil and gas development on ferruginous hawks
WallaceReoccupancyBreedingTerritoriesAppendixS1.pdf
No full textGrassland and shrubland birds are declining globally due in part to anthropogenic habitat modification. Because population performance of these species is also influenced by non-anthropogenic factors, it is important to incorporate all relevant ecological drivers into demographic models. We used design-based sampling and occupancy models to test relationships of environmental factors that influence raptor demographics with re-occupancy of breeding territories by ferruginous hawks (Buteo regalis) across Wyoming, USA, 2011-2013. We also tested correlations of territory re-occupancy with oil and gas infrastructure-a leading cause of habitat modification throughout the range of this species of conservation concern. Probability of re-occupancy was not related to any covariates we investigated in 2011, had a strong negative relationship with cover of sagebrush (Artemisia spp.) in 2012, was slightly higher for territories with artificial platforms than other nest substrates in 2013, and had a positive relationship with abundance of ground squirrels (Urocitellus spp.) that was strong in 2012 and weak in 2013. Associations with roads were weak and varied by year, road-type, and scale: in 2012, re-occupancy probability had a weak positive correlation with density of roads not associated with oil and gas fields at the territory-scale; however, in 2013 re-occupancy had a very weak negative correlation with density of oil and gas field roads near nest sites (≤ 500 m). Although our results indicate re-occupancy of breeding territories by ferruginous hawks was compatible with densities of anthropogenic infrastructure in our study area, the lack of relationships between oil and gas well density and territory re-occupancy may have occurred because pre-treatment data were unavailable. We used probabilistic sampling at a broad spatial extent, methods to account for imperfect detection, and conducted extensive prey sampling; nonetheless, future research using before-after-control-impact designs is needed to fully assess impacts of oil and gas development on ferruginous hawks
Verification of Intraovum Transmission of a Microsporidium of Vertebrates: Pseudoloma neurophilia Infecting the Zebrafish, Danio rerio
Get PDFDirect transmission from parents to offspring, referred to as vertical transmission, occurs within essentially all major groups of pathogens. Several microsporidia (Phylum Microsporidia) that infect arthropods employ this mode of transmission, and various lines of evidence have suggested this might occur with certain fish microsporidia. The microsporidium, Pseudoloma neurophilia, is a common pathogen of the laboratory zebrafish, Danio rerio. We previously verified that this parasite is easily transmitted horizontally, but previous studies also indicated that maternal transmission occurs. We report here direct observation of Pseudoloma neurophilia in the progeny of infected zebrafish that were reared in isolation, including microscopic visualization of the parasite in all major stages of development. Histological examination of larval fish reared in isolation from a group spawn showed microsporidian spores in the resorbing yolk sac of a fish. Infections were also observed in three of 36 juvenile fish. Eggs from a second group spawn of 30 infected fish were examined using a stereomicroscope and the infection was observed from 4 to 48 hours post-fertilization in two embryos. Intraovum infections were detected in embryos from 4 of 27 pairs of infected fish that were spawned based on qPCR detection of P. neurophilia DNA. The prevalence of intraovum infections from the four spawns containing infected embryos was low (~1%) based on calculation of prevalence using a maximum likelihood analysis for pooled samples. Parasite DNA was detected in the water following spawning of 11 of the infected pairs, suggesting there was also potential for extraovum transmission in these spawning events. Our study represents the first direct observation of vertical transmission within a developing embryo of a microsporidian parasite in a vertebrate. The low prevalence of vertical transmission in embryos is consistent with observations of some other fish pathogens that are also readily transmitted by both vertical and horizontal routes
Halocline water modification and along-slope advection at the Laptev Sea continental margin
Get PDFA general pattern in water mass distribution and
potential shelf–basin exchange is revealed at the Laptev Sea
continental slope based on hydrochemical and stable oxygen
isotope data from the summers 2005–2009. Despite considerable
interannual variations, a frontal system can be inferred
between shelf, continental slope and central Eurasian Basin
waters in the upper 100 m of the water column along the continental
slope. Net sea-ice melt is consistently found at the
continental slope. However, the sea-ice meltwater signal is
independent from the local retreat of the ice cover and appears
to be advected from upwind locations.
In addition to the along-slope frontal system at the continental
shelf break, a strong gradient is identified on the
Laptev Sea shelf between 122° E and 126° E with an eastward
increase of riverine and sea-ice related brine water contents.
These waters cross the shelf break at ~140° E and feed
the low-salinity halocline water (LSHW, salinity S < 33) in
the upper 50 m of the water column. High silicate concentrations
in Laptev Sea bottom waters may lead to speculation
about a link to the local silicate maximum found within the
salinity range of ~33 to 34.5, typical for the Lower Halocline
Water (LHW) at the continental slope. However brine
signatures and nutrient ratios from the central Laptev Sea
differ from those observed at the continental slope. Thus a
significant contribution of Laptev Sea bottom waters to the
LHW at the continental slope can be excluded. The silicate maximum within the LHW at the continental slope may be
formed locally or at the outer Laptev Sea shelf. Similar to
the advection of the sea-ice melt signal along the Laptev Sea
continental slope, the nutrient signal at 50–70 m water depth
within the LHW might also be fed by advection parallel to the
slope. Thus, our analyses suggest that advective processes
from upstream locations play a significant role in the halocline
formation in the northern Laptev Sea.This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Copernicus Publications on behalf of the European Geosciences Union. The published article can be found at: http://www.ocean-science.net/
Landscape Context Mediates Avian Habitat Choice in Tropical Forest Restoration
Get PDFBirds both promote and prosper from forest restoration. The ecosystem functions birds perform can increase the pace of forest regeneration and, correspondingly, increase the available habitat for birds and other forest-dependent species. The aim of this study was to learn how tropical forest restoration treatments interact with landscape tree cover to affect the structure and composition of a diverse bird assemblage. We sampled bird communities over two years in 13 restoration sites and two old-growth forests in southern Costa Rica. Restoration sites were established on degraded farmlands in a variety of landscape contexts, and each included a 0.25-ha plantation, island treatment (trees planted in patches), and unplanted control. We analyzed four attributes of bird communities including frugivore abundance, nectarivore abundance, migrant insectivore richness, and compositional similarity of bird communities in restoration plots to bird communities in old-growth forests. All four bird community variables were greater in plantations and/or islands than in control treatments. Frugivore and nectarivore abundance decreased with increasing tree cover in the landscape surrounding restoration plots, whereas compositional similarity to old-growth forests was greatest in plantations embedded in landscapes with high tree cover. Migrant insectivore richness was unaffected by landscape tree cover. Our results agree with previous studies showing that increasing levels of investment in active restoration are positively related to bird richness and abundance, but differences in the effects of landscape tree cover on foraging guilds and community composition suggest that trade-offs between biodiversity conservation and bird-mediated ecosystem functioning may be important for prioritizing restoration sites
ReidJLeightonForestryLandscapeContextMediates_SupportingInformation.pdf
No full textBirds both promote and prosper from forest restoration. The ecosystem functions birds perform can increase the pace of
forest regeneration and, correspondingly, increase the available habitat for birds and other forest-dependent species. The
aim of this study was to learn how tropical forest restoration treatments interact with landscape tree cover to affect the
structure and composition of a diverse bird assemblage. We sampled bird communities over two years in 13 restoration
sites and two old-growth forests in southern Costa Rica. Restoration sites were established on degraded farmlands in a
variety of landscape contexts, and each included a 0.25-ha plantation, island treatment (trees planted in patches), and
unplanted control. We analyzed four attributes of bird communities including frugivore abundance, nectarivore abundance,
migrant insectivore richness, and compositional similarity of bird communities in restoration plots to bird communities in
old-growth forests. All four bird community variables were greater in plantations and/or islands than in control treatments.
Frugivore and nectarivore abundance decreased with increasing tree cover in the landscape surrounding restoration plots,
whereas compositional similarity to old-growth forests was greatest in plantations embedded in landscapes with high tree
cover. Migrant insectivore richness was unaffected by landscape tree cover. Our results agree with previous studies showing
that increasing levels of investment in active restoration are positively related to bird richness and abundance, but
differences in the effects of landscape tree cover on foraging guilds and community composition suggest that trade-offs
between biodiversity conservation and bird-mediated ecosystem functioning may be important for prioritizing restoration
sites
Insight into Hydrogen Bonding of Uranyl Hydroxide Layers and Capsules by Use of ¹H Magic-Angle Spinning NMR Spectroscopy
Get PDFSolid-state ¹H magic-angle spinning (MAS) NMR was used to investigate local proton environments in anhydrous [UO₂(OH)₂] (α-UOH) and hydrated uranyl hydroxide [(UO₂)₄O(OH₆ 6·5H₂O (metaschoepite). For the metaschoepite material, proton resonances of the μ₂-OH hydroxyl and interlayer waters were resolved, with two-dimensional (2D) double-quantum (DQ) ¹H–¹H NMR correlation experiments revealing strong dipolar interactions between these different proton species. The experimental NMR results were combined with first-principles CASTEP GIPAW (gauge including projector-augmented wave) chemical shift calculations to develop correlations between hydrogen-bond strength and observed ¹H NMR chemical shifts. These NMR correlations allowed characterization of local hydrogen-bond environments in uranyl U₂₄ capsules and of changes in hydrogen bonding that occurred during thermal dehydration of metaschoepite.This is the publisher’s final pdf. The published article is copyrighted by the American Chemical Society and can be found at: http://pubs.acs.org/journal/jpccck/about.htm