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In 785 mother–child (50% male) pairs from a longitudinal epidemiological birth cohort, we investigated associations between inflammation-related epigenetic polygenic risk scores (i-ePGS), environmental exposures, cognitive function, and child and adolescent internalizing and externalizing problems. We examined prenatal and postnatal effects. For externalizing problems, one prenatal effect was found: i-ePGS at birth associated with higher externalizing problems (ages 7–15) indirectly through lower cognitive function (age 7). For internalizing problems, we identified two effects. For a prenatal effect, i-ePGS at birth associated with higher internalizing symptoms via continuity in i-ePGS at age 7. For a postnatal effect, higher postnatal adversity exposure (birth through age 7) associated with higher internalizing problems (ages 7–15) via higher i-ePGS (age 7). Hence, externalizing problems were related mainly to prenatal effects involving lower cognitive function, whereas internalizing problems appeared related to both prenatal and postnatal effects. The present study supports a link between i-ePGS and child and adolescent mental health.
This paper addresses activities carried out in a late-sixteenth or seventeenth century Maya council house (popol nah) just before its abandonment. Structure 719 at the site of Zacpeten in the central Peten lakes district is considered a noble residence remodeled into a council house with an adjacent temple. Excavations revealed quantities of de facto refuse inside the structure's two rooms and around the exterior; recent studies focused on ceramics, lithics, faunal remains, and net sinkers. The back room held abundant lithics and diverse fauna, with evidence of grinding red pigment and snapping obsidian prismatic blades into segments for fashioning arrow points. Pottery and faunal remains indicate feasting, as well as possible use of animal parts in ritual and in making ceremonial objects. The Group 719 complex served as a center of production of various goods and community ritual until its abrupt abandonment, likely in the first decade or so of the eighteenth century.
In this article, we consider how the Postclassic Kowoj Maya of the central Peten lakes region of El Petén, Guatemala utilized mana in conjunction with their ritual objects and spolia to mediate between the natural and supernatural worlds. In many cultures worldwide and throughout time, mana (magical or spiritual powers that provide people and objects with a living force) transforms the ordinary into the spiritually powerful. The Kowojs imbued incense burners and buildings with mana, thus facilitating a connection with their ancestors. We examine the manufacturing recipe of a group of incense burners and the civic-ceremonial buildings at Zacpeten to argue that the Kowoj used these objects to mediate among the living, the dead, and the supernatural realms. Ultimately, by empowering these objects with mana, the Kowoj constructed a universe where they regularly communicated with their ancestors and built structures that ensouled their historical consciousness.
While NGC 1068 has received much attention in recent years, little is known of the large-scale dynamics and physical state of the ionized gas in this nearby Seyfert galaxy and, in particular, its connection with the nuclear activity. We have used the Hawaii Imaging Fabry-Perot Interferometer (HIFI) at the CFHT to obtain detailed spectrophotometry at 65 kms−1 resolution (FWHM) over the Hα and neighbouring [N II] lines. The final maps are derived from 100 000 fits to spectra taken at 0.4″ increments over a 200″ field-of-view. (A higher resolution study which concentrates on the circumnuclear, optical emission and its relation to the radio jet is presented at this conference by Cecil & Bland.)
Early-onset conduct problems (CP) are a key predictor of adult criminality and poor mental health. While previous studies suggest that both genetic and environmental risks play an important role in the development of early-onset CP, little is known about potential biological processes underlying these associations. In this study, we examined prospective associations between DNA methylation (cord blood at birth) and trajectories of CP (4–13 years), using data drawn from the Avon Longitudinal Study of Parents and Children. Methylomic variation at seven loci across the genome (false discovery rate < 0.05) differentiated children who go on to develop early-onset (n = 174) versus low (n = 86) CP, including sites in the vicinity of the monoglyceride lipase (MGLL) gene (involved in endocannabinoid signaling and pain perception). Subthreshold associations in the vicinity of three candidate genes for CP (monoamine oxidase A [MAOA], brain-derived neurotrophic factor [BDNF], and FK506 binding protein 5 [FKBP5]) were also identified. Within the early-onset CP group, methylation levels of the identified sites did not distinguish children who will go on to persist versus desist in CP behavior over time. Overall, we found that several of the identified sites correlated with prenatal exposures, and none were linked to known genetic methylation quantitative trait loci. Findings contribute to a better understanding of epigenetic patterns associated with early-onset CP.
The effects of large-scale galactic winds in active galaxies may be far-reaching. It has been suggested that the Hubble sequence can be understood in terms of a galaxy's greater ability to sustain winds with increasing bulge-to-disk ratio. The large-scale circulation of gas associated with these galactic winds might help explain the mass-metallicity relation between galaxies and the metallicity-radius relation within galaxies. Galactic winds probably contribute non-negligibly to the cosmic X-ray background and may be involved in the quasar absorption-line phenomenon. The cosmological implications of the wind phenomenon have been widely explored in the context of proto-galaxies and quasars. The extremely energetic galactic winds that were likely associated with galaxy formation almost certainly played a key role in heating and ionizing the intergalactic medium at high redshifts and may have created the seeds for the large-scale structure we see today.
The Hawaii Imaging Fabry-Perot Interferometer (HIFI) was used to produce a large data cube of the edge-on SBc galaxy NGC 3079 covering Hα + [NII] λλ6548, 6583. The complete two-dimensional coverage of the Fabry-Perot data allowed us to derive the general flow pattern of the nuclear gas that constitutes the energetic superbubble.
I summarize the results of our multifrequency study of the helically twisted jets in the Seyfert galaxy NGC 4258. [N II], Hα, and [O III] Fabry-Perot datacubes obtained with the HIFI system on the U. Hawaii 2.2m telescope form the basis of this work. ROSAT x-ray multiband images (HRI & PSPC), CO spectra, and unpublished VLA 6 and 20 cm maps are correlated with these spectral grids. Together these data reveal clear signatures of high-velocity (> 300 km s−1) shocks along the jets that suggest efficient entrainment of ambient molecular gas.
To understand the evolution of giant stars, it is important to pin down the masses for Cepheids. The 7– to 10–day “bump” Cepheids imply lower than evolutionary mass (60%). Recent theoretical work, though, indicates that for Cepheids with periods of 15 to 16 days, the best understanding of the light curves results from using evolutionary masses.
This paper serves two purposes: 1) to discuss the latest improvements in nonlinear pulsation theory indicating the ability to resolve features such as the “Christy bump” on the light curves and 2) to show from the results of a bump model and recent observations that mass loss is one of the possible explanations for the mass discrepancy problem between evolutionary and pulsation theories. Recent observations by Sanford and Gow of Los Alamos and Bernat (McDonald Observatory) show that extensive mass loss has occurred in the evolution of the M supergiant α Orionis.
Tututepec was a regional capital that dominated much of southern Oaxaca, Mexico, during the Late Postclassic period (A.D. 1100-1522). This article synthesizes the results of compositional (neutron activation and petrography), stylistic, and iconographic analyses of pottery from commoner household excavations at Tututepec to address questions concerning ceramic production and distribution and also to shed light on aspects of political economy and domestic ritual at the capital. The study focuses primarily on Mixteca-Puebla polychromes, painted serving vessels bearing complex decorative motifs. Our compositional analyses, interpreted in light of the bedrock geology of the region, indicate that commoners obtained at least six to ten distinct varieties of pottery made from raw materials available locally within greater Tututepec. We argue that households probably acquired pottery through a central marketplace at the capital. In addition, our study demonstrates that commoners had regular access to polychromes from multiple producers, challenging the widespread notion that these vessels were restricted to elites who controlled their production. We argue that polychrome serving vessels played a prominent role in commonly occurring domestic rituals. Furthermore, commoners appear to have consciously selected vessels painted with imagery associated with warfare and sacrifice, suggesting that they actively supported the official imperial ideology of Tututepec.
Plumpton plain is situated on the top of the South Downs, roughly 600 feet above sea level, six miles north-east of Brighton and four miles north-west of Lewes (fig. 1). From its western end a broad spur slopes gently southwards from the northern escarpment of the Downs, lying between Moustone Valley on the south-east and Faulkners Bottom on the west. Most of this Downland is covered with a dense scrub of gorse, thorn and bramble, and with large patches of bracken and heather. A series of broad paths running roughly at right angles with one another has been cut through this vegetation to facilitate the preservation of game. Along the main ridge of the spur running north and south is a broad gallop which, at a height of 600 feet O.D., passes through a group of earthworks situated 1500 feet from the north edge of the Downs and 2300 feet east of Streathill Farm. This group was the primary object of bur investigations and will be referred to as Site A (fig. 2).
Site B (fig. 3) lies a quarter of a mile to the south-east of Site A on a small lateral spur jutting between the twin heads of Moustone Bottom. The only visible evidence of prehistoric occupation was a quantity of coarse gritty sherds and calcined flints on the surface to the south-east of a low bank and ditch which runs across the spur.
Several groups of lynchets enclosing square Celtic fields are to be seen in the neighbourhood of these two sites. They lie principally to the south-east of Site A and to the south of Site B.
Our understanding of the role of the initial surface on atomic layer
deposition (ALD) of Cu diffusion barrier materials is limited by the
complexity of the sequential reactions and the heterogeneous nature of
typical dielectric substrates. The atomically controlled surface chemistry
of self-assembled monolayers (SAMs) provides a means of creating model
substrates for ALD. Here we report on ALD of WCxNy
films on SAMs derived from bromoundecyltrichlorosilane adsorbed on silicon
dioxide. The as-prepared SAM is macroscopically ordered with the expected
Br-termination and has a well-defined chemical composition as determined by
contact angle measurements and X-ray photoelectron spectroscopy,
respectively. Temperature programmed desorption spectroscopy confirms that
the SAM is stable to 550°C. It survives multiple cycles of ALD at 300°C as
evidenced by the detection of mass fragments characteristic of the alkyl
chain and supported by the persistence of a Br 2p peak at 71 eV. X-ray
fluorescence, ellipsometry and atomic force microscopy reveal that the
underlying SAM influences WCxNy film coverage, thickness, and
Lead(II) oxides are involved in various advanced materials. Their high volatility as compared to that of other elements makes chemical routes to such materials especially attractive. Various synthetic routes to lead(II) alkoxides have therefore been estimated. They display a strong tendency to undergo spontaneous condensation reactions, giving oxoalkoxides Pb4O(OR)6 (R = tBu, iPr, Et). Reaction between Pb4O(OEt)6 and [Nb(OEt)5l2 does not proceed by simple addition of the alkoxides, but the lead tetranuclear oxoalkoxide is transformed to a hexanuclear one, Pb6O4 (OEt)4 , whose oxo ligands bear Nb(OEt)5 moieties, the overall formula being Pb6O4 (OEt)4 [Nb(OEt)5]4 1. The stoichiometry between the two metals corresponds to that of the PNM ceramic, and 207Pb NMR has been used as a tool to study the reactivity of 1 in the presence of various modifiers and magnesium ethoxide.
This paper presents examples of the use of transmission electron microscopy to characterize matrix/reinforcement interaction in titanium aluminide matrix composites reinforced with continuous SCS-6 type SiC. As a result of the high temperature required for consolidating this type composite, reaction products form in the interface. Using diffraction and x-ray energy dispersive spectroscopy techniques, reaction products in Ti3Al and Ti2AINb alloy matrix composites have been identified. TiC1 –x and Ti5 Si3 compounds are common in these composites, with AlTi3C also present depending on consolidation temperature and matrix composition. Residual stress calculations indicate that these reaction products may be subject to cracking during cooling from consolidationtemperatures.
In this study, we explore the effects of alkyl surface terminations on ZnO for inverted, planar ZnO/poly(3-hexylthiophene) (P3HT) solar cells using two different attachment chemistries. Octadecylthiol (ODT) and octadecyltriethoxysilane (OTES) molecules were used to create 18-carbon alkyl surface molecular layers on sol gel-derived ZnO surfaces. Molecular layer formation was confirmed and characterized using water contact angle measurements, infrared (IR) transmission measurements, and X-ray photoelectron spectroscopy (XPS). The performances of the ZnO/P3HT photovoltaic cells made from ODT- and OTES-functionalized ZnO were compared. The ODT-modified devices had higher efficiencies than OTES-modified devices, suggesting that differences in the attachment scheme affect the efficiency of charge transfer through the molecular layers at the treated ZnO surface.
Corals live in close association with bacterial communities, but the nature of the relationship is still poorly understood. In this study, three scleractinian coral species, Galaxea fascicularis, Pavona cactus and Turbinaria reniformis were incubated under different laboratory conditions, and the composition of the bacterial community associated with their tissue or skeleton was compared between species or between species and seawater using denaturing gradient gel electrophoresis (DGGE). The amount of dissolved organic carbon (DOC) excreted and the mucus glycoconjugate composition were also determined for each species. The aim of the study was to assess if the bacterial community composition was species-specific or linked either to the seawater composition, or to the quality and quantity of carbon released by each coral. Results obtained showed that DOC release was significantly different (P < 0.0001) for the three species, with the highest excretion rate for G. fascicularis. Also, the mucus of G. fascicularis and P. cactus mainly contained galactose and glucose whereas the mucus of T. reniformis contained more glucose and xylose. Cluster analyses of microbial community composition showed that the bacterial community was species-specific in the coral tissue but not in the skeleton, in all conditions. It remained specific when corals were incubated in the same or in different aquaria, and under different seawater renewal rates. Since DOC release rates and bacterial composition were both different according to the coral species considered, a link might be suggested between the two parameters. Sequencing of DGGE bands indicated that some bacterial phylotypes were consistently retrieved in all samples of a given species.