Higher Body Mass Index Values Do Not Impact Physical Function and Lower-Extremity Muscle Strength Performance in Active Older Individuals

International Journal of Exercise Science 15(3): 330-340, 2022. This study examined the potential impact of BMI on physical function and lower-extremity muscle strength (leg extension and flexion peak torque) performance in active/trained older individuals. Sixty-four active/trained older individuals were enrolled, and later allocated to groups according to BMI categories (normal [≤ 24.9 kg/m2], overweight [25 to 29.9 kg/m2] and obese [≥ 30 kg/m2]). Sixty-four active/trained older individuals were enrolled, and later allocated to groups according to BMI categories (normal [≤ 24.9 kg/m2], overweight [25 to 29.9 kg/m2] and obese [≥ 30 kg/m2]). Assessments were conducted in two separate visits to the laboratory. In the first visit, participants underwent measures of height, body mass, and peak torque leg extension and flexion using an isokinetic dynamometer. On visit two, participants performed the 30-second Sit and Stand test (30SST), Timed Up and Go (TUG), and 6-minute Walk (6MW) tests. ANOVA one-way was used to analyze the data and significance was set at P \u3c .05. One-way ANOVAs did not reveal significance differences among BMI categories for leg extension peak torque (F(2,61) = 1.11; P = 0.336), leg flexion peak torque (F(2,61) = 1.22; P = 0.303), 30SST (F(2,61) =1.28; P = 0.285), TUG (F(2,61) = 0.238; P = 0.789), and 6MW (F(2,61) = 2.52; P = 0.089)]. Our findings indicated that for older individuals who exercise regularly, physical function tests which mimic ordinary activities of daily living, are not impacted by BMI status. Thus, being physically active may counteract some of the negative effects of high BMI observed in the older adult population

The VMC survey III : Mass-loss rates and luminosities of LMC AGB stars

Context. Asymptotic giant branch (AGB) stars are major contributors to both the chemical enrichment of the interstellar medium and the integrated light of galaxies. Despite its importance, the AGB is one of the least understood phases of stellar evolution. The main difficulties associated with detailed modelling of the AGB are related to the mass-loss process and the 3rd dredge-up efficiency Aims. We provide direct measures of mass-loss rates and luminosities for a complete sample of AGB stars in the Large Magellanic Cloud, disentangling the C- and O-rich stellar populations. Methods. Dust radiative transfer models are presented for all 374 AGB stars candidates in one of the fields observed by the new VISTA survey of the Magellanic Clouds (VMC). Mass-loss rates, luminosities and a classification of C-and O-rich stars are derived by fitting the models to the spectral energy distribution (SED) obtained by combining VMC data with existing optical, near-, and mid-infrared photometry. Results. The classification technique is reliable at a level of - at worst -75% and significantly better for the reddest dusty stars. We classified none of the stars with a relevant mass-loss rate as O-rich, and we can exclude the presence of more than one dusty O-rich star at a similar to 94% level. The bolometric luminosity function we obtained is fully consistent with most of the literature data on the LMC and with the prediction of theoretical models, with a peak of the C-star distribution at M-bol similar or equal to -4.8 mag and no stars brighter than the classical AGB tip, at M-bol = -7.1 mag. Conclusions. This exploratory study shows that our method provides reliable mass-loss rates, luminosities and chemical classifications for all AGB stars. These results offer already important constraints to AGB evolutionary models. Most of our conclusions, especially for the rarer dust-enshrouded extreme AGB stars, are however strongly limited by the relatively small area covered by our study. Forthcoming VMC observations will easily remove this limitation.Peer reviewe

The VMC Survey - XIII : Type II Cepheids in the Large Magellanic Cloud

Date of Acceptance: 27/10/2014The VISTA (Visible and Infrared Survey Telescope for Astronomy) survey of the Magellanic Clouds System (VMC) is collecting deep Ks-band time-series photometry of the pulsating variable stars hosted in the system formed by the two Magellanic Clouds and the Bridge connecting them. In this paper, we have analysed a sample of 130 Large Magellanic Cloud (LMC) Type II Cepheids (T2CEPs) found in tiles with complete or near-complete VMC observations for which identification and optical magnitudes were obtained from the OGLE III (Optical Gravitational Lensing Experiment) survey. We present J and Ks light curves for all 130 pulsators, including 41 BL Her, 62 W Vir (12 pW Vir) and 27 RV Tau variables. We complement our near-infrared photometry with the V magnitudes from the OGLE III survey, allowing us to build a variety of period-luminosity (PL), period-luminosity-colour (PLC) and period-Wesenheit (PW) relationships, including any combination of the V, J, Ks filters and valid for BL Her and W Vir classes. These relationships were calibrated in terms of the LMC distance modulus, while an independent absolute calibration of the PL(Ks) and the PW(Ks, V) was derived on the basis of distances obtained from Hubble Space Telescope parallaxes and Baade-Wesselink technique. When applied to the LMC and to the Galactic globular clusters hosting T2CEPs, these relations seem to show that (1) the two Population II standard candles RR Lyrae and T2CEPs give results in excellent agreement with each other; (2) there is a discrepancy of ~0.1 mag between Population II standard candles and classical Cepheids when the distances are gauged in a similar way for all the quoted pulsators. However, given the uncertainties, this discrepancy is within the formal 1σ uncertainties.Peer reviewedFinal Accepted Versio

Longitudinal development of initial, chronic and mucoid Pseudomonas aeruginosa infection in young children with cystic fibrosis

BACKGROUND: While the emergence of chronic and mucoid Pseudomonas aeruginosa (Pa) infection are both associated with poorer outcomes among CF patients, their relationship is poorly understood. We examined the longitudinal relationship of incident, chronic and mucoid Pa in a contemporary, young CF cohort in the current era of Pa eradication therapy. METHODS: This retrospective cohort was comprised of patients in the U.S. CF Foundation Patient Registry born 2006-2015, diagnosed before age 2, and with at least 3 respiratory cultures annually. Incidence and age-specific prevalence of Pa infection stages (initial and chronic [≥ 3Pa+cultures in prior year]) and of mucoid Pa were summarized. Transition times and the interaction between Pa stage and acquisition of mucoid Pa were examined via Cox models. RESULTS: Among the 5592 CF patients in the cohort followed to a mean age of 5.5years, 64% (n=3580) acquired Pa. Of those, 13% (n=455) developed chronic Pa and 17% (n=594) cultured mucoid Pa. Among those with mucoid Pa, 36% (211/594) had it on their first recorded Pa+culture, while mucoid Pa emerged at or after entering the chronic stage in 12% (73/594). Mucoidy was associated with significantly increased risk of transition to chronic Pa infection (HR=2.59, 95% CI 2.11, 3.19). CONCLUSIONS: Two-thirds of early-diagnosed young children with CF acquired Pa during a median 5.6years of follow up, among whom 13% developed chronic Pa and 17% acquired mucoid Pa. Contrary to our hypothesis, 87% of young children who developed mucoid Pa did so before becoming chronically infected

Preliminary results for RR Lyrae stars and Classical Cepheids from the Vista Magellanic Cloud (VMC) Survey

The Vista Magellanic Cloud (VMC, PI M.R. Cioni) survey is collecting $K_S$-band time series photometry of the system formed by the two Magellanic Clouds (MC) and the "bridge" that connects them. These data are used to build $K_S$-band light curves of the MC RR Lyrae stars and Classical Cepheids and determine absolute distances and the 3D geometry of the whole system using the $K$-band period luminosity ($PLK_S$), the period - luminosity - color ($PLC$) and the Wesenhiet relations applicable to these types of variables. As an example of the survey potential we present results from the VMC observations of two fields centered respectively on the South Ecliptic Pole and the 30 Doradus star forming region of the Large Magellanic Cloud. The VMC $K_S$-band light curves of the RR Lyrae stars in these two regions have very good photometric quality with typical errors for the individual data points in the range of $\sim$ 0.02 to 0.05 mag. The Cepheids have excellent light curves (typical errors of $\sim$ 0.01 mag). The average $K_S$ magnitudes derived for both types of variables were used to derive $PLK_S$ relations that are in general good agreement within the errors with the literature data, and show a smaller scatter than previous studies.Comment: 7 pages, 6 figure. Accepted for publication in Astrophysics and Space Science. Following a presentation at the conference "The Fundamental Cosmic Distance Scale: State of the Art and the Gaia Perspective", Naples, May 201

Chaos and Quantum-Classical Correspondence via Phase Space Distribution Functions

Quantum-classical correspondence in conservative chaotic Hamiltonian systems is examined using a uniform structure measure for quantal and classical phase space distribution functions. The similarities and differences between quantum and classical time-evolving distribution functions are exposed by both analytical and numerical means. The quantum-classical correspondence of low-order statistical moments is also studied. The results shed considerable light on quantum-classical correspondence.Comment: 16 pages, 5 figures, to appear in Physical Review

The VMC survey - XIV : First results on the look-back time star formation rate tomography of the Small Magellanic Cloud

Date of Acceptance: 20/01/2015We analyse deep images from the VISTA survey of the Magellanic Clouds in the YJKs filters, covering 14 deg2 (10 tiles), split into 120 subregions, and comprising the main body and Wing of the Small Magellanic Cloud (SMC). We apply a colour-magnitude diagram reconstruction method that returns their best-fitting star formation rate SFR(t), age-metallicity relation (AMR), distance and mean reddening, together with 68 per cent confidence intervals. The distance data can be approximated by a plane tilted in the East-West direction with a mean inclination of 39°, although deviations of up to ±3 kpc suggest a distorted and warped disc. After assigning to every observed star a probability of belonging to a given age-metallicity interval, we build high-resolution population maps. These dramatically reveal the flocculent nature of the young star-forming regions and the nearly smooth features traced by older stellar generations. They document the formation of the SMC Wing at ages <0.2 Gyr and the peak of star formation in the SMC Bar at ~40 Myr. We clearly detect periods of enhanced star formation at 1.5 and 5 Gyr. The former is possibly related to a new feature found in the AMR, which suggests ingestion of metal-poor gas at ages slightly larger than 1 Gyr. The latter constitutes a major period of stellar mass formation. We confirm that the SFR(t) was moderately low at even older ages.Peer reviewe