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Trends in Trans Fatty Acids Reformulations of US Supermarket and Brand-Name Foods From 2007 Through 2011
Introduction: Although some US food manufacturers have reduced trans fatty acids (TFA) in their products, it is unknown how much TFA is being reduced, whether pace of reformulation has changed over time, or whether reformulations vary by food type or manufacturer. Methods: In 2007, we identified 360 brand-name products in major US supermarkets that contained 0.5 g TFA or more per serving. In 2008, 2010, and 2011, product labels were re-examined to determine TFA content; ingredients lists were also examined in 2011 for partially hydrogenated vegetable oils (PHVO). We assessed changes in TFA content among the 270 products sold in all years between 2007 and 2011 and conducted sensitivity analyses on the 90 products discontinued after 2007. Results: By 2011, 178 (66%) of the 270 products had reduced TFA content. Most reformulated products (146 of 178, 82%) reduced TFA to less than 0.5 g per serving, although half of these 146 still contained PHVO. Among all 270 products, mean TFA content decreased 49% between 2007 and 2011, from 1.9 to 0.9 g per serving. Yet, mean TFA reduction slowed over time, from 30.3% (2007–2008) to 12.1% (2008–2010) to 3.4% (2010–2011) (P value for trend < .001). This slowing pace was due to both fewer reformulations among TFA-containing products at start of each period and smaller TFA reductions among reformulated products. Reformulations also varied substantially by both food category and manufacturer, with some eliminating or nearly eliminating TFA and others showing no significant changes. Sensitivity analyses were similar to main findings. Conclusions: Some US products and food manufacturers have made progress in reducing TFA, but substantial variation exists by food type and by parent company, and overall progress has significantly slowed over time. Because TFA consumption is harmful even at low levels, our results emphasize the need for continued efforts toward reformulating or discontinuing foods to eliminate PHVO
Improving Interpretation of the Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function Scale for Specific Tasks in Community-Dwelling Older Adults
Background and purpose: New generic patient-reported outcomes like the Patient-Reported Outcomes Measurement Information System (PROMIS) are available to physical therapists to assess physical function. However, the interpretation of the PROMIS Physical Function (PF) T-score is abstract because it references the United States average and not specific tasks. The purposes of this study were to (1) determine convergent validity of the PROMIS PF scale with physical performance tests; (2) compare predicted performance test values to normative data; and (3) identify sets of PROMIS PF items similar to performance tests that also scale in increasing difficulty and align with normative data.
Methods: Community-dwelling older adults (n = 45; age = 77.1 ± 4.6 years) were recruited for this cross-sectional analysis of PROMIS PF and physical performance tests. The modified Physical Performance Test (mPPT), a multicomponent test of mostly timed items, was completed during the same session as the PROMIS PF scale. Regression analysis examined the relationship of mPPT total and component scores (walking velocity, stair ascent, and 5 times sit to stand) with the PROMIS PF scale T-scores. Normative data were compared with regression-predicted mPPT timed performance across PROMIS PF T-scores. The PROMIS PF items most similar to walking, stair ascent, or sit to stand were identified and then PROMIS PF model parameter-calibrated T-scores for these items were compared alongside normative data.
Results and discussion: There were statistically significant correlations (r = 0.32-0.64) between PROMIS PF T-score and mPPT total and component scores. Regression-predicted times for walking, stair ascent, and sit-to-stand tasks (based on T-scores) aligned with published normative values for older adults. Selected PF items for stair ascent and walking scaled well to discriminate increasing difficulty; however, sit-to-stand items discriminated only lower levels of functioning.
Conclusions: The PROMIS PF T-scores showed convergent validity with physical performance and aligned with published normative data. While the findings are not predictive of individual performance, they improve clinical interpretation by estimating a range of expected performance for walking, stair ascent, and sit to stand. These findings support application of T-scores in physical therapy testing, goal setting, and wellness plans of care for community-dwelling older adults
Inhibitor binding mode and allosteric regulation of Na+-glucose symporters.
Sodium-dependent glucose transporters (SGLTs) exploit sodium gradients to transport sugars across the plasma membrane. Due to their role in renal sugar reabsorption, SGLTs are targets for the treatment of type 2 diabetes. Current therapeutics are phlorizin derivatives that contain a sugar moiety bound to an aromatic aglycon tail. Here, we develop structural models of human SGLT1/2 in complex with inhibitors by combining computational and functional studies. Inhibitors bind with the sugar moiety in the sugar pocket and the aglycon tail in the extracellular vestibule. The binding poses corroborate mutagenesis studies and suggest a partial closure of the outer gate upon binding. The models also reveal a putative Na+ binding site in hSGLT1 whose disruption reduces the transport stoichiometry to the value observed in hSGLT2 and increases inhibition by aglycon tails. Our work demonstrates that subtype selectivity arises from Na+-regulated outer gate closure and a variable region in extracellular loop EL5
High-Resolution Spectroscopic Study of Extremely Metal-Poor Star Candidates from the SkyMapper Survey
The SkyMapper Southern Sky Survey is carrying out a search for the most
metal-poor stars in the Galaxy. It identifies candidates by way of its unique
filter set that allows for estimation of stellar atmospheric parameters. The
set includes a narrow filter centered on the Ca II K 3933A line, enabling a
robust estimate of stellar metallicity. Promising candidates are then confirmed
with spectroscopy. We present the analysis of Magellan-MIKE high-resolution
spectroscopy of 122 metal-poor stars found by SkyMapper in the first two years
of commissioning observations. 41 stars have [Fe/H] <= -3.0. Nine have [Fe/H]
<= -3.5, with three at [Fe/H] ~ -4. A 1D LTE abundance analysis of the elements
Li, C, Na, Mg, Al, Si, Ca, Sc, Ti, Cr, Mn, Co, Ni, Zn, Sr, Ba and Eu shows
these stars have [X/Fe] ratios typical of other halo stars. One star with low
[X/Fe]
[X/Fe values appears to be "Fe-enhanced," while another star has an extremely
large [Sr/Ba] ratio: >2. Only one other star is known to have a comparable
value. Seven stars are "CEMP-no" stars ([C/Fe] > 0.7, [Ba/Fe] < 0). 21 stars
exhibit mild r-process element enhancements (0.3 <=[Eu/Fe] < 1.0), while four
stars have [Eu/Fe] >= 1.0. These results demonstrate the ability to identify
extremely metal-poor stars from SkyMapper photometry, pointing to increased
sample sizes and a better characterization of the metal-poor tail of the halo
metallicity distribution function in the future.Comment: Minor corrections to text, missing data added to Tables 3 and 4;
updated to match published version. Complete tables included in sourc
A left-handed simplicial action for euclidean general relativity
An action for simplicial euclidean general relativity involving only
left-handed fields is presented. The simplicial theory is shown to converge to
continuum general relativity in the Plebanski formulation as the simplicial
complex is refined. This contrasts with the Regge model for which Miller and
Brewin have shown that the full field equations are much more restrictive than
Einstein's in the continuum limit. The action and field equations of the
proposed model are also significantly simpler then those of the Regge model
when written directly in terms of their fundamental variables.
An entirely analogous hypercubic lattice theory, which approximates
Plebanski's form of general relativity is also presented.Comment: Version 3. Adds current home address + slight corrections to
references of version 2. Version 2 = substantially clarified form of version
1. 29 pages, 4 figures, Latex, uses psfig.sty to insert postscript figures.
psfig.sty included in mailing, also available from this archiv
Overview of Advanced LIGO Adaptive Optics
This is an overview of the adaptive optics used in Advanced LIGO (aLIGO),
known as the thermal compensation system (TCS). The thermal compensation system
was designed to minimize thermally-induced spatial distortions in the
interferometer optical modes and to provide some correction for static
curvature errors in the core optics of aLIGO. The TCS is comprised of ring
heater actuators, spatially tunable CO laser projectors and Hartmann
wavefront sensors. The system meets the requirements of correcting for nominal
distortion in Advanced LIGO to a maximum residual error of 5.4nm, weighted
across the laser beam, for up to 125W of laser input power into the
interferometer
Update of P2X receptor properties and their pharmacology: IUPHAR Review 30
The known seven mammalian receptor subunits (P2X1–7) form cationic channels gated by ATP. Three subunits compose a receptor channel. Each subunit is a polypeptide consisting of two transmembrane regions (TM1 and TM2), intracellular N- and C-termini, and a bulky extracellular loop. Crystallization allowed the identification of the 3D structure and gating cycle of P2X receptors. The agonist-binding pocket is located at the intersection of two neighbouring subunits. In addition to the mammalian P2X receptors, their primitive ligand-gated counterparts with little structural similarity have also been cloned. Selective agonists for P2X receptor subtypes are not available, but medicinal chemistry supplied a range of subtype-selective antagonists, as well as positive and negative allosteric modulators. Knockout mice and selective antagonists helped to identify pathological functions due to defective P2X receptors, such as male infertility (P2X1), hearing loss (P2X2), pain/cough (P2X3), neuropathic pain (P2X4), inflammatory bone loss (P2X5), and faulty immune reactions (P2X7)
Overview of Advanced LIGO Adaptive Optics
This is an overview of the adaptive optics used in Advanced LIGO (aLIGO), known as the thermal compensation system (TCS). The TCS was designed to minimize thermally induced spatial distortions in the interferometer optical modes and to provide some correction for static curvature errors in the core optics of aLIGO. The TCS is comprised of ring heater actuators, spatially tunable CO_2
laser projectors, and Hartmann wavefront sensors. The system meets the requirements of correcting for nominal distortion in aLIGO to a maximum residual error of 5.4 nm rms, weighted across the laser beam, for up to 125 W of laser input power into the interferometer
``Sum over Surfaces'' form of Loop Quantum Gravity
We derive a spacetime formulation of quantum general relativity from
(hamiltonian) loop quantum gravity. In particular, we study the quantum
propagator that evolves the 3-geometry in proper time. We show that the
perturbation expansion of this operator is finite and computable order by
order. By giving a graphical representation a' la Feynman of this expansion, we
find that the theory can be expressed as a sum over topologically inequivalent
(branched, colored) 2d surfaces in 4d. The contribution of one surface to the
sum is given by the product of one factor per branching point of the surface.
Therefore branching points play the role of elementary vertices of the theory.
Their value is determined by the matrix elements of the hamiltonian constraint,
which are known. The formulation we obtain can be viewed as a continuum version
of Reisenberger's simplicial quantum gravity. Also, it has the same structure
as the Ooguri-Crane-Yetter 4d topological field theory, with a few key
differences that illuminate the relation between quantum gravity and TQFT.
Finally, we suggests that certain new terms should be added to the hamiltonian
constraint in order to implement a ``crossing'' symmetry related to 4d
diffeomorphism invariance.Comment: Seriously revised version. LaTeX, with revtex and epsfi
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