Effect of oral creatine supplementation on near-maximal strength and repeated sets of high-intensity bench press exercise

This study examined the effects of 26 days of oral creatine monohydrate (Cr) supplementation on near-maximal muscular strength, high-intensity bench press performance, and body composition. Eighteen male powerlifters with at least 2 years resistance training experience took part in this 28-day experiment. Pre and postmeasurements (Days 1 and 28) were taken of near-maximal muscular strength, body mass, and % body fat. There were two periods of supplementation Days 2 to 6 and Days 7 to 27. ANOVA and t-tests revealed that Cr supplementation significantly increased body mass and lean body mass with no changes in % body fat. Significant increases in 3-RM strength occurred in both groups, both absolute and relative to body mass; the increases were greater in the Cr group. The change in total repetitions also increased significantly with Cr supplementation both in absolute terms and relative to body mass, while no significant change was seen in the placebo (P) group. Creatine supplementation caused significant changes in the number of BP reps in Sets 1, 4, and 5. No changes occurred in the P group. It appears that 26 days of Cr supplementation significantly improves muscular strength and repeated near-maximal BP performance, and induces changes in body composition.

Finite element analysis of flow patterns near geological lenses in hydrodynamic and hydrothermal systems

We use theoretical and numerical methods to investigate the general pore-fluid flow patterns near geological lenses in hydrodynamic and hydrothermal systems respectively. Analytical solutions have been rigorously derived for the pore-fluid velocity, stream function and excess pore-fluid pressure near a circular lens in a hydrodynamic system. These analytical solutions provide not only a better understanding of the physics behind the problem, but also a valuable benchmark solution for validating any numerical method. Since a geological lens is surrounded by a medium of large extent in nature and the finite element method is efficient at modelling only media of finite size, the determination of the size of the computational domain of a finite element model, which is often overlooked by numerical analysts, is very important in order to ensure both the efficiency of the method and the accuracy of the numerical solution obtained. To highlight this issue, we use the derived analytical solutions to deduce a rigorous mathematical formula for designing the computational domain size of a finite element model. The proposed mathematical formula has indicated that, no matter how fine the mesh or how high the order of elements, the desired accuracy of a finite element solution for pore-fluid flow near a geological lens cannot be achieved unless the size of the finite element model is determined appropriately. Once the finite element computational model has been appropriately designed and validated in a hydrodynamic system, it is used to examine general pore-fluid flow patterns near geological lenses in hydrothermal systems. Some interesting conclusions on the behaviour of geological lenses in hydrodynamic and hydrothermal systems have been reached through the analytical and numerical analyses carried out in this paper.

Effect of increased lung expansion on lung growth and development near midgestation in fetal sheep

Obstruction of the fetal trachea is a potent stimulus for fetal lung growth and may have therapeutic potential in human fetuses with lung hypoplasia. However, the effects of increased lung expansion on lung development near midgestation, which is the preferred timing for fetal intervention, have not been well studied. Our aim was to determine the effects of increased lung expansion on lung development at 75-90 d of gestation in fetal sheep. In three groups of fetuses (n = 4 for each), the trachea was occluded for either 10 [10-d tracheal occlusion (TO) group] or 15 d (15-d TO group) or left intact (control fetuses). TO for both 10 and 15 d caused fetal hydrops, resulting in significantly increased fetal body weights. Both periods of TO significantly increased total lung DNA contents from 99.8 +/- 10.1 to 246.0 +/- 5.3 and 246.9 +/- 48.7 mg in 10- and 15-d TO fetuses, respectively. TO for 10 and 15 d also increased airspace diameter, although the percentage of lung occupied by airspace was not increased in 10-d TO fetuses due to large increases in interairway distances; this resulted from a large increase in mesenchymal tissue. The interairway distances at 15 d of TO were reduced compared with the 10-d value but were still similar to 30% larger than control values. We conclude that TO at

Visible and near-infrared luminescent Eu(3+) or Er(3+) doped laponite-derived xerogels and thick films: Structural and spectroscopic properties

Laponite-derived materials represent promising materials for optical applications. In this work, Eu(3+)- or Er(3+)-doped laponite xerogels and films were prepared from colloidal dispersion. Homogeneous, crack-free and transparent single layers were deposited on soda-lime substrates with a thickness of 10 mu m. Structural and spectroscopic properties were analyzed by thermal analyses, X-ray diffractometry, transmission electron microscopy, infrared spectroscopy, and luminescence spectroscopy. The addition of a rare earth ion to the laponite does not promote any changes in thermal stability or phase transition. Laponite clay was identified after annealing up to 500 degrees C, with a decrease in basal spacing when the annealing temperature is changed from 100 degrees C to 500 degrees C. Enstatite polymorphs and amorphous silicate phases were observed after heat treatment at 700 degrees C and 900 degrees C. Stationary and time-dependent luminescence spectra in the visible region for Eu(3+), and (5)D(0) lifetime are discussed in terms of thermal treatment and structural evolution. In the layered host, the Eu(3+) ions are distributed in many different local environments. However, Eu(3+) ions were found to occupy at least two symmetry sites, and the ions are preferentially incorporated into the crystalline enstatite for the materials annealed at 700 degrees C and 900 degrees C. A (5)D(0) lifetime of 1.3 ms and 3.1 ms was obtained for Eu(3+) ions in an amorphous silicate and crystalline MgSiO(3) local environment, respectively. Strong Er(3+) emission at the 1550 nm region was observed for the materials annealed at 900 degrees C, with a bandwidth of 44 nm. (C) 2008 Elsevier B.V. All rights reserved.

Sol-gel preparation of near-infrared broadband emitting Er(3+)-doped SiO(2)-Ta(2)O(5) nanocomposite films

This article reports a study on the preparation, densification process, and structural and optical properties of SiO(2)-Ta(2)O(5) nanocomposite films obtained by the sol-gel process. The films were doped with Er(3+) and the Si:Ta molar ratio was 90:10. Values of refractive index, thickness and vibrational modes in terms of the number of layers and thermal annealing time are described for the films. The densification process is accompanied by OH group elimination, increase in the refractive index, and changes in film thickness. Full densification of the film is acquired after 90 min of annealing at 900 degrees C. The onset of crystallization and devitrification, with the growth of Ta(2)O(5) nanocrystals occurs with film densification, evidenced by high-resolution transmission electron microscopy. The Er(3+)-doped nanocomposite annealed at 900 degrees C consists of Ta(2)O(5) nanoparticles, with sizes around 2 nm, dispersed in the SiO(2) amorphous phase. The main emission peak of the film is detected at around 1532 nm, which can be assigned to the (4)I(13/2)->(4)I(15/2) transition of the Er(3+) ions present in the nanocomposites. This band has a full width at half medium of 64 nm, and the lifetime measured for the (4)I(13/2) levels is 5.4 ms, which is broader compared to those of other silicate systems. In conclusion, the films obtained in this work are excellent candidates for use as active planar waveguide. (C) 2010 Elsevier B.V. All rights reserved.

Direct measurement of pulse distortion near the zero-dispersion wavelength in an optical fiber by frequency-resolved optical gating

The technique of frequency-resolved optical gating is used to characterize the intensity and the phase of picosecond pulses after propagation through 700 m of fiber at close to the zero-dispersion wavelength. Using the frequency-resolved optical gating technique, we directly measure the severe temporal distortion resulting from the interplay between self-phase modulation and higher-order dispersion in this regime. The measured intensity and phase of the pulses after propagation are found to be in good agreement with the predictions of numerical simulations with the nonlinear Schrodinger equation. (C) 1997 Optical Society of America.

Assessment of flow in perforating arteries during intracranial aneurysm surgery using intraoperative near-infrared indocyanine green videoangiography

OBJECTIVE: Perforating arteries are commonly involved during the surgical dissection and clipping of intracranial aneurysms. Occlusion of perforating arteries is responsible for ischemic infarction and poor outcome. The goal of this study is to describe the usefulness of near-infrared indocyanine green videoangiography (ICGA) for the intraoperative assessment of blood flow in perforating arteries that are visible in the surgical field during clipping of intracranial aneurysms. In addition, we analyzed the incidence of perforating vessels involved during the aneurysm surgery and the incidence of ischemic infarct caused by compromised small arteries. METHODS: Sixty patients with 64 aneurysms were surgically treated and prospectively included in this study. Intraoperative ICGA was performed using a surgical microscope (Carl Zeiss Co., Oberkochen, Germany) with integrated ICGA technology. The presence and involvement of perforating arteries were analyzed in the microsurgical field during surgical dissection and clip application. Assessment of vascular patency after clipping was also investigated. Only those small arteries that were not visible on preoperative digital subtraction angiography were considered for analysis. RESULTS: The ICGA was able to visualize flow in all patients in whom perforating vessels were found in the microscope field. Among 36 patients whose perforating vessels were visible on ICGA, 11 (30%) presented a close relation between the aneurysm and perforating arteries. In one (9%) of these 11 patients, ICGA showed occlusion of a P1 perforating artery after clip application, which led to immediate correction of the clip confirmed by immediate reestablishment of flow visible with ICGA without clinical consequences. Four patients (6.7%) presented with postoperative perforating artery infarct, three of whom had perforating arteries that were not visible or distant from the aneurysm. CONCLUSION: The involvement of perforating arteries during clip application for aneurysm occlusion is a usual finding. Intraoperative ICGA may provide visual information with regard to the patency of these small vessels.

POISSON DISTRIBUTION TO ANALYZE NEAR-THRESHOLD MOTOR EVOKED POTENTIALS

Motor unit action potentials (MUAPs) evoked by repetitive, low-intensity transcranial magnetic stimulation can be modeled as a Poisson process. A mathematical consequence of such a model is that the ratio of the variance to the mean of the amplitudes of motor evoked potentials (MEPs) should provide an estimate of the mean size of the individual MUAPs that summate to generate each MEP. We found that this is, in fact, the case. Our finding thus supports the use of the Poisson distribution to model MEP generation and indicates that this model enables characterization of the motor unit population that contributes to near-threshold MEPs. Muscle Nerve 42: 825-828, 2010

Density of the Near Threatened jaguar Panthera onca in the caatinga of north-eastern Brazil

We report the first estimate of jaguar density in the semi-arid caatinga biome of north-eastern Brazil. During August-October 2007, in the Serra da Capivara National Park, we used camera traps to identify and count jaguars. Jaguar abundance and density were calculated using mark-recapture models. In a sampling effort of 1,249 camera-trap-nights we identified 12 adult jaguars and estimated an 2 abundance of 14 +/- 3.6 jaguars in an area of 524 km(2), i.e. a density of 2.67 +/- 1.00 jaguars per 100 km(2). This estimate is higher than in most other Brazilian biomes and indicates Serra da Capivara National Park as an important reserve for protecting jaguars in north-eastern Brazil.