Long-chain polyunsaturated fatty acids (LCPUFA) including docosahexaenoic acid (DHA) are essential for normal vision and neurodevelopment. DHA accretion in utero occurs primarily in the last ...trimester of pregnancy to support rapid growth and brain development. Premature infants, born before this process is complete, are relatively deficient in this essential fatty acid. Very low birth weight (VLBW) infants remain deficient for a long period of time due to ineffective conversion from precursor fatty acids, lower fat stores and a limited nutritional provision of DHA after birth. In addition to long-term visual and neurodevelopmental risks, VLBW infants have significant morbidity and mortality from diseases specific to premature birth, including bronchopulmonary dysplasia, necrotizing enterocolitis, and retinopathy of prematurity. There is increasing evidence that DHA has protective benefits against these disease states. The aim of this article is to identify the unique needs of premature infants, review the current recommendations for LCPUFA provision in infants and discuss the caveats and innovative new ways to overcome the DHA deficiency through postnatal supplementation, with the long-term goal of improving morbidity and mortality in this at-risk population.
An unusually deep (V,I) imaging dataset for the Virgo supergiant M 87 with the Hubble Space Telescope ACS successfully resolves its brightest red-giant stars, reaching MI(lim) = −2.5. After assessing ...the photometric completeness and biasses, we use this material to estimate the metallicity distribution for the inner halo of M 87, finding that the distribution is very broad and likely to peak near m/H ≃ −0.4 and perhaps higher. The shape of the MDF strongly resembles that of the inner halo for the nearby giant E galaxy NGC 5128. As a byproduct of our study, we also obtain a preliminary measurement of the distance to M 87 with the TRGB (red-giant branch tip) method; the result is (m − M)0 = 31.12±0.14 (d = 16.7±0.9 Mpc). Averaging this result with three other recent techniques give a weighted mean d(M87) = (16.4 ± 0.5) Mpc.
The size-weight illusion is a phenomenon where a smaller object is perceived heavier than an equally weighted larger object. The sensorimotor mismatch theory proposed that this illusion occurs ...because of a mismatch between efferent motor commands and afferent sensory feedback received when lifting large and small objects (i.e., the application of too little and too much lifting force, respectively). This explanation has been undermined by studies demonstrating a separation between the perceived weight of objects and the lifting forces that are applied on them. However, this research suffers from inconsistencies in the choice of lifting force measures reported. Therefore, we examined the contribution of sensorimotor mismatch in the perception of weight in the size-weight illusion and in non-size-weight illusion stimuli and evaluated the use of a lifting force aggregate measure comprising the four most common lifting force measures used in previous research. In doing so, the sensorimotor mismatch theory was mostly supported. In a size-weight illusion experiment, the lifting forces correlated with weight perception and, contrary to some earlier research, did not adapt over time. In a non-size-weight illusion experiment, switches between lifting light and heavy objects resulted in perceiving the weight of these objects differently compared to no switch trials, which mirrored differences in the manner participants applied forces on the objects. Additionally, we reveal that our force aggregate measure can allow for a more sensitive and objective examination of the effects of lifting forces on objects.
Girls Will Be Girls (GWBG) delivers a substantive queer-feminist critique of heteronormative animus toward women and gay men through jokes that weaponize that animus for insurgent purposes. The ...film's rape and abortion jokes showcase the provocative notion that negative representations of femininity might be wielded strategically and, in fact, more resonantly because they resist recuperation by marginalizing normative hierarchies. GBWG's enactment of gay male femininity deploys queer dissidence by ameliorating pain through mockery while emphasizing the costs of heteronormative and patriarchal inflictions. This essay offers a test case for a queer feminist politics-one that, without discarding the imperatives for and rewards of more materially grounded political work, mines the critical as well as affective affordances of rage, mockery, and indignity against heteronormativity's arbitrary but still formidable injunctions. A queer feminist reading of camp denaturalizes heteronormativity with a potency that queer theory and feminist theory might harness yet more effectually in less divided collaboration.
Abstract Light echoes of debris disks around active stars can reveal disk structure and composition even when disks are not spatially resolved. Unfortunately, distinguishing reflected light from ...quiescent starlight and unexpected post-peak flare structure is challenging, especially for edge-on geometries where the time delay between observed flare photons and light scattered from the near side of the disk is short. Here, we take advantage of the fact that scattered light from a dusty disk is polarized, depending on the location of the scattering site and the orientation of the disk relative to a distant observer. Filtering reflected light into its polarized components allows echoes to stand out in predictable ways. We test this idea with a simple model for a disk around an active M dwarf. Our results demonstrate that the use of polarimetric data of flaring stars can significantly enhance echo signals relative to starlight and yield more robust and accurate fits to disk parameters compared to analyses based on the total intensity alone.
Context.
The extended stellar halos of galaxies contain important clues for investigating their assembly history and evolution.
Aims.
We investigate the resolved stellar content and the extended halo ...of NGC 5128 as a function of galactocentric distance, and trace the halo outward to its currently detectable limits.
Methods.
We used
Hubble
Space Telescope images obtained with the WFPC2, ACS, and WFC3 cameras equipped with
F
606
W
and
F
814
W
filters to resolve individual red giant branch (RGB) stars in 28 independent pointings across the halo of NGC 5128. The stellar halo analysis for 14 of these pointings is presented here for the first time. Star counts from deep
V
I
color-magnitude diagrams reaching at least 1.5 mag below the tip of the RGB are used to derive the surface density distribution of the halo. The contamination by Milky Way stars is assessed with a new control field, with models, and by combining optical and near-IR photometry.
Results.
We present a new calibration of the WFC3
F
606
W
+
F
814
W
photometry to the ground-based
V
I
photometric system. The photometry shows that the stellar halo of NGC 5128 is dominated by old RGB stars that are present in all fields. The
V
-band surface brightness of fields changes from 23 to 32 mag arcsec
−2
between the innermost field only 8.3 kpc from the galaxy center to our outermost halo fields, which are located 140 kpc away from the center along the major axis and 92 kpc along the minor axis. Within the inner ∼30 kpc, we also find evidence for a 2 − 3 Gyr old population traced by asymptotic giant branch stars that are brighter than the tip of the RGB. This population contributes only up to 10% in total stellar mass if it is 2 Gyr old, but a larger fraction of 30 − 40% is required if its age is 3 Gyr. The stellar surface density profile is well fit by a classic
r
1/4
curve or a simple power-law form ∼
r
−3.1
over the full radial range, with no obvious break in the slope, but with large field-to-field scatter. The ellipticity measured from integrated-light photometry in the inner parts,
e
= (
b
/
a
) = 0.77, flattens to
e
= 0.54 ± 0.02 beyond 30 kpc. Considering the flattening of the outer halo, the projection of the elliptical isophote on the semimajor axis for our most distant field reaches nearly 30 effective radii.
Abstract
In the classical world, “official” rationalistic medicine made therapeutic use of excrement, urine and other substances that modern humans normally regard as repulsive (this was even true of ...Galen, the culminating authority); and popular medicine seems to have done so on a large scale. Such practices, which finally lost their professional though not their popular acceptability in the 18th century, have been studied to good purpose by other historians, but they have never been explained in a satisfactory fashion, partly because the relevant evidence is highly diverse. The present paper, by considering the long term (pre-Greek as well as Greek and Roman) and all the relevant contexts, including ancient feelings of disgust and the general state of ancient pharmacology, and by probing people’s subconscious motives, attempts to establish a multi-factor explanation. This explanation balances traditions, beliefs about the inherent qualities, physical and magical, of natural substances, and the psychological needs of both healers and the sick.
Association of receptor activity-modifying proteins (RAMP1-3) with the G protein-coupled receptor (GPCR) calcitonin receptor-like receptor (CLR) enables selective recognition of the peptides ...calcitonin gene-related peptide (CGRP) and adrenomedullin (AM) that have diverse functions in the cardiovascular and lymphatic systems. How peptides selectively bind GPCR:RAMP complexes is unknown. We report crystal structures of CGRP analog-bound CLR:RAMP1 and AM-bound CLR:RAMP2 extracellular domain heterodimers at 2.5 and 1.8 Å resolutions, respectively. The peptides similarly occupy a shared binding site on CLR with conformations characterized by a β-turn structure near their C termini rather than the α-helical structure common to peptides that bind related GPCRs. The RAMPs augment the binding site with distinct contacts to the variable C-terminal peptide residues and elicit subtly different CLR conformations. The structures and accompanying pharmacology data reveal how a class of accessory membrane proteins modulate ligand binding of a GPCR and may inform drug development targeting CLR:RAMP complexes.
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•Crystal structures reveal how CGRP and AM peptides bind their heterodimeric receptors•CGRP and AM occupy a shared binding site on CLR with minimal contact to the RAMPs•Peptide binding modes were confirmed for intact receptors in cells by mutagenesis•Peptide selectivity arises from RAMP-specific contacts and subtle alteration of CLR
Booe et al. report two crystal structures that reveal how selectivity of the GPCR CLR for CGRP and AM peptides is modulated by RAMP proteins. The peptides similarly occupy a shared binding site on CLR. RAMPs augment the binding site with distinct contacts to the peptides and subtly alter CLR.
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