Exercise intervention does not reduce the likelihood of VO2max underestimation in older adults with hypertension.

The present study aimed to investigate whether training status would influence the capacity of a verification phase (VER) to confirm maximal oxygen uptake (VO2max) of a previous graded exercise test (GXT) in individuals with hypertension. Twelve older adults with hypertension (8 women) were recruited. Using a within-subject design, participants performed a treadmill GXT to exhaustion followed by a multistage VER both before and after a 12-wkcombined exercise training programme. Individual VO2max, respiratory exchange ratio (RER), maximal heart rate (HRmax), and rating of perceived exertion (RPE) were measured during both GXT and VER tests. Absolute and relative VO2max values were higher in VER than in GXT at baseline, but only absolute VO2max differed between bouts post-intervention (all p < 0.05). Individual VO2max comparisons revealed that 75% of the participants (9/12) achieved a VO2max value that was ≥3% during VER both before (range: +4.9% to +21%) and after the intervention (range: +3.4% to +18.8%), whereas 91.7% (11/12) of the tests would have been validated as a maximal effort if the classic criteria were employed. A 12-wk combined training intervention could not improve the capacity of older adults with hypertension to achieve VO2max during a GXT, as assessed by VER.

Maximal Oxygen Uptake Is Underestimated during Incremental Testing in Hypertensive Older Adults: Findings from the HAEL Study.

PURPOSE: The present cross-sectional study aimed to investigate whether a maximal oxygen uptake (V˙O2max) verification phase (VER) could improve the accuracy of a previous graded exercise test (GXT) to assess individual V˙O2max in hypertensive individuals. METHODS: Thirty-three older adults with hypertension (24 women) taking part in the Hypertension Approaches in the Elderly Study (NCT03264443) were recruited. Briefly, after performing a treadmill GXT to exhaustion, participants rested for 10 min and underwent a multistage VER to confirm GXT results. Individual V˙O2max, RER, maximal heart rate (HRmax), and RPE were measured during both GXT and VER tests. Mean values were compared between bouts using paired sample t-tests, and V˙O2max was also compared between GXT and VER on an individual basis. RESULTS: Testing was well tolerated by all participants. Both absolute (P = 0.011) and relative (P = 0.014) V˙O2max values were higher in VER than that in GXT. RER (P < 0.001) and RPE (P = 0.002) were lower in VER, whereas HRmax (P = 0.286) was not different between the two trials. Individual V˙O2max comparisons revealed that 54.6% of the participants (18/33) achieved a V˙O2max value that was ≥3% during VER (mean = 13.5%, range = +3% to +22.1%, ES = 0.062), whereas 87.9% (29/33) of the tests would have been validated as a maximal effort if the classic criteria were used (i.e., V̇O2 plateau or at least two secondary criteria). CONCLUSION: In sedentary older individuals with hypertension, GXT to exhaustion underestimated V˙O2max in more than half of tested participants, even when established, but criticized criteria were used to confirm whether a maximal effort was attained. Using VER after GXT is a quick approach to assist with the verification of an individual's V˙O2max.

Radon kinetics in a natural indoor radon chamber.

An unusual 180 m3 storage room in the basement of a two-story laboratory building is unventilated, and separated from occupiable rooms by double steel doors. The space completely borders on soil through the concrete floor and two of its concrete walls. The room also contains a separate inner chamber with 1 m thick concrete walls designed to damp vibrations in the room above it. The space boasts a relatively high radon level, 1083 Bq m-3, which varies with local outdoor environmental conditions. Measurements were made of radon concentrations at various locations and heights within the facility. More than a year of continuous radon concentration data corresponding to a single location are also available, along with measurements of indoor and outdoor pressure, temperature, and humidity. Data were also collected with as many as five fans placed in different locations and cycled on for variable time periods. First order linear kinetic models were created to explain the observed approaches to steady state due to changing conditions and wash-out resulting from intentional ventilation. Results demonstrate a good fit between changes in the radon concentration level and the developed compartmental models. However, no significant differences were observed between radon concentration at different locations or heights in the chamber.

Intercomparison of Commercially Available Active Radon Measurement Devices in a Discovered Radon Chamber.

An unventilated 70 m underground space, with 2.1 m high ceilings and an inner set of concrete walls to damp vibrations, was discovered to have relatively stable radon levels of ~1,080 Bq m over a 1-y period. The addition of radium sources was not required to achieve high and somewhat variable radon levels, as these arise naturally in the space. Several active radon monitoring devices designed for homeowners, radon screeners, radon mitigation professionals, and researchers were tested in the space. These devices were variable in both cost and intended user sophistication. Data were collected at specific time intervals that varied for each device. A cellphone was deployed with an available camera application to periodically capture photographs of the displays of devices not enabled for automatic temporal recording. Attempts were made to alter the radon concentration using fans, radium-laden objects, and radon impermeable sheets. Statistical methods were employed to compare the device's performance under the minor radon transients produced by the addition of Ra sources during the test period. The evaluation of the overall accuracy, noise, and response to transients revealed highly affordable devices that may be useful for future research applications. While unsuitable for precise calibrations at stable radon levels, the space was determined to be adequate as a radon chamber for general research purposes.

The Effects of Radiation and Emitted Light Transport on the Positional Response of 11 cm × 42.5 cm × 5.5 cm NaI(Tl) Detectors.

Experiments were performed with 30 11 cm × 42.5 cm × 5.5 cm NaI(Tl) detectors to better understand their positional response. Spectra were collected using 0.02 to 0.15 MBq point sources of Am, Cs, Co, and Ba positioned on lines parallel and perpendicular to the long axis of the crystal along both the narrow and wide detector faces as well as at different distances from them. A greater density of positions was sampled at the ends of the detector, and repeated measurements were made to examine potential gain drifts during the experiment. Spectroscopic peak counts, spectroscopic pulse heights, and net counts were analyzed. Empirical equations were fit to the aforementioned data for each specific source energy as a function of source position. In addition, a Monte Carlo radiation transport code was used to simulate the expected positionally variable response based solely upon radiation absorption. The simulated radiation transport efficiency functions were compared to the experimental data. The effects of the geometric radiation efficiency, the attenuation and scattering of emitted light within the scintillation crystal, and combined effects such as nonuniformity of the photomultiplier tube, photocathode response, and crystal irregularities were then distinguished. Functions describing each effect were derived. The results suggest potential new corrections to data obtained with large scintillation detectors as well as a novel approach to partial positional gamma-ray detection with minimal collimation, given that the energy resolution is within reason for particular photopeaks.

Displasia cráneo-fronto-nasal. Delineación del espectro fenotípico en 43 pacientes y estudio de 7 casos familiares / Craneofrontonasal dysplasia. Delineation of the phenotypic expression in 43 patients and study of 7 families cases

Introducción. La displasia craneofrontonasal es un síndrome malformativo donde coexisten craneosinostosis e hipertelorismo y anomalías extracraneales en pacientes femeninos, cuyo mecanismo hereditario está aún en discusión. Material y métodos. Se estudió clínica, radiológica y citogenéticamente a 43 pacientes afectados, incluyendo 7 casos familiares, lo que permitió el estudio del patrón hereditario. Resultados. Se demostró que el espectro clínico completo incluye hallazgos no reportados o cuya frecuencia se ha descrito como menor: cabello crespo, rizado, de origen no familiar y de inicio tardío; fisuras faciales pterigium colli y/o axilar, clavículas anómalas, hipoplasia mamaria inilareral y acortamiento ispilateral de la extremidad pélvica; se corroboraron radiográficamente las fisuras faciales y las alteraciones esqueléticas óseas. Se describen formas frustras o de afección mínima en mujeres. El cariotipo fue normal en todos los casos. Conclusiones. El estudio familiar detectó formas mínimas, además de expresión diferencial en ambos sexos, y que el gen responsable está localizado en el cromosoma X