A rigid body model for the assessment of glenohumeral joint mechanics: Influence of osseous defects on range of motion and dislocation

© 2016. The purpose of this study was to employ subject-specific computer models to evaluate the interaction of glenohumeral range-of-motion and Hill-Sachs humeral head bone defect size on engagement and shoulder dislocation. We hypothesized that the rate of engagement would increase as defect size increased, and that greater shoulder ROM would engage smaller defects. Three dimensional computer models of 12 shoulders were created. For each shoulder, additional models were created with simulated Hill-Sachs defects of varying severities (XS=15%, S=22.5%, M=30%, L=37.5%, XL=45% and XXL=52.5% of the humeral head diameter, respectively). Rotational motion simulations without translation were conducted. The simulations ended if the defect engaged the anterior glenoid rim with resultant dislocation. The results showed that the rate of engagement was significantly different between defect sizes (0.00

Discovery of Reflection Nebulosity Around Five Vega-like Stars

Coronagraphic optical observations of six Vega-like stars reveal reflection nebulosities, five of which were previously unknown. The nebulosities illuminated by HD 4881, HD 23362, HD 23680, HD 26676, and HD 49662 resemble that of the Pleiades, indicating an interstellar origin for dust grains. The reflection nebulosity around HD 123160 has a double-arm morphology, but no disk-like feature is seen as close as 2.5 arcsec from the star in K-band adaptive optics data. We demonstrate that uniform density dust clouds surrounding HD 23362, HD 23680 and HD 123160 can account for the observed 12-100 micron spectral energy distributions. For HD 4881, HD 26676, and HD 49662 an additional emission source, such as from a circumstellar disk or non-equilibrium grain heating, is required to fit the 12-25 micron data. These results indicate that in some cases, particularly for Vega-like stars located beyond the Local Bubble (>100 pc), the dust responsible for excess thermal emission may originate from the interstellar medium rather than from a planetary debris system.Comment: The Astrophysical Journal, in press for March, 2002 (32 pages, 13 figures

Primordial Helium-3 Redux: The Helium Isotope Ratio of the Orion Nebula*

We report the first direct measurement of the helium isotope ratio, 3He/4He, outside of the Local Interstellar Cloud, as part of science-verification observations with the upgraded CRyogenic InfraRed Echelle Spectrograph. Our determination of 3He/4He is based on metastable He i* absorption along the line of sight toward Θ2A Ori in the Orion Nebula. We measure a value 3He/4He = (1.77 ± 0.13) × 10−4, which is just ∼40% above the primordial relative abundance of these isotopes, assuming the Standard Model of particle physics and cosmology, (3He/4He)p = (1.257 ± 0.017) × 10−4. We calculate a suite of galactic chemical evolution simulations to study the Galactic build up of these isotopes, using the yields from Limongi & Chieffi for stars in the mass range M = 8–100 M⊙ and Lagarde et al. for M = 0.8–8 M⊙. We find that these simulations simultaneously reproduce the Orion and protosolar 3He/4He values if the calculations are initialized with a primordial ratio ${\left({}^{3}\mathrm{He}{/}^{4}\mathrm{He}\right)}_{{\rm{p}}}=(1.043\pm 0.089)\times {10}^{-4}$. Even though the quoted error does not include the model uncertainty, this determination agrees with the Standard Model value to within ∼2σ. We also use the present-day Galactic abundance of deuterium (D/H), helium (He/H), and 3He/4He to infer an empirical limit on the primordial 3He abundance, ${\left({}^{3}\mathrm{He}/{\rm{H}}\right)}_{{\rm{p}}}\leqslant (1.09\pm 0.18)\times {10}^{-5}$, which also agrees with the Standard Model value. We point out that it is becoming increasingly difficult to explain the discrepant primordial 7Li/H abundance with nonstandard physics, without breaking the remarkable simultaneous agreement of three primordial element ratios (D/H, 4He/H, and 3He/4He) with the Standard Model values

Ursinus College Bulletin Vol. 9, No. 9, June 1893

A digitized copy of the June 1893 Ursinus College Bulletin.https://digitalcommons.ursinus.edu/ucbulletin/1087/thumbnail.jp

Unraveling the directional link between adiposity and inflammation: a bidirectional mendelian randomization approach

<b>Context</b>: Associations between adiposity and circulating inflammation markers are assumed to be causal, although the direction of the relationship has not been proven. <b>Objective</b>: The aim of the study was to explore the causal direction of the relationship between adiposity and inflammation using a bidirectional Mendelian randomization approach. <b>Methods</b>: In the PROSPER study of 5804 elderly patients, we related C-reactive protein (CRP) single nucleotide polymorphisms (SNPs) (rs1800947 and rs1205) and adiposity SNPs (FTO and MC4R) to body mass index (BMI) as well as circulating levels of CRP and leptin. We gave each individual two allele scores ranging from zero to 4, counting each pair of alleles related to CRP levels or BMI. <b>Results</b>: With increasing CRP allele score, there was a stepwise decrease in CRP levels (P for trend < 0.0001) and a 1.98 mg/liter difference between extremes of the allele score distribution, but there was no associated change in BMI or leptin levels (P ≥ 0.89). By contrast, adiposity allele score was associated with 1) an increase in BMI (1.2 kg/m2 difference between extremes; P for trend 0.002); 2) an increase in circulating leptin (5.77 ng/ml difference between extremes; P for trend 0.0027); and 3) increased CRP levels (1.24 mg/liter difference between extremes; P for trend 0.002). <b>Conclusions</b>: Greater adiposity conferred by FTO and MC4R SNPs led to higher CRP levels, with no evidence for any reverse pathway. Future studies should extend our findings to other circulating inflammatory parameters. This study illustrates the potential power of Mendelian randomization to dissect directions of causality between intercorrelated metabolic factors

The ``Outside-In'' Outburst of HT Cassiopeiae

We present results from photometric observations of the dwarf nova system HT Cas during the eruption of November 1995. The data include the first two--colour observations of an eclipse on the rise to outburst. They show that during the rise to outburst the disc deviates significantly from steady state models, but the inclusion of an inner-disc truncation radius of about 4 $R_{wd}$ and a ``flared'' disc of semi-opening angle of $10^{\circ}$ produces acceptable fits. The disc is found to have expanded at the start of the outburst to about $0.41R_{L1}$, as compared to quiescent measurements. The accretion disc then gradually decreases in radius reaching $<0.32R_{L1}$ during the last stages of the eruption. Quiescent eclipses were also observed prior to and after the eruption and a revised ephemeris is calculated.Comment: 9 pages, 11 figures, to appear in MNRA

Leptin Predicts Diabetes but Not Cardiovascular Disease: Results from a large prospective study in an elderly population

OBJECTIVE—To clarify the association of circulating levels of leptin with risk for cardiovascular disease (CVD) events and new-onset diabetes in men and women