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Presents a study which investigated soft X-ray emission from double-pulse laser-produced plasma. Separation of two pulses; Method used in measuring the emitted X-ray flux; Evidence for an enhancement of the soft X-ray conversion efficiency.

Presents comparative x-ray spectroscopy of various Z elements with wavelength calibration of laser-heated plasma. X-ray studies on laser-heated plasmas; Details on the experiment; Discussion on the results of the study.

Presents a study which investigated the relative conversion efficiency of laser energy into x radiation as a function of irradiance for planar copper targets. Methods used in the study; Data on relative conversion efficiency as a function of laser pulse irradiance; Measurements of relative conversion efficiency; Factors considered in the dependence of the conversion efficiency on laser pulse duration and wavelength.

The purpose of this pilot study was to examine the effects of a combined cardiorespiratory and resistance exercise training program of short duration on the cardiorespiratory fitness, strength endurance, task specific functional muscle capacity, body composition and quality of life (QOL) in women breast cancer survivors. Sixteen subjects were randomly assigned to either a training (n = 8; age: 50 ± 5 yrs) or control non-exercising group (n = 8; age: 51 ± 10 yrs). The training group followed an 8-week exercise program consisting of 3 weekly sessions of 90-mm duration, supervised by an experienced investigator and divided into resistance exercises and aerobic training. Before and after the intervention period, all of the subjects performed a cardiorespiratory test to measure peak oxygen uptake (VO2peak), a dynamic strength endurance test (maximum number of repetitions for chest and leg press exercise at 30-35% and 100-110% of body mass, respectively) and a sit-stand test. Quality of life was assessed using the European Organization for Research and Treatment of Cancer QLQ-C30 (EORTC-C30) questionnaire. In response to training, QOL, VO2peak (mean 3.9 ml/kg/min; 95% CI, 0.93, 6.90) performance in leg press (17.9 kg; 95% CI, 12.8, 22.4) and sit-stand test (-0.67 s; 95% CI, -0.52, -1.2) improved (p≤0.05). We observed no significant changes in the control group. Combined cardiorespiratory and resistance training, even of very brief duration, improves the QOL and the overall physical fitness of women breast cancer survivors. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the effects of Rotor, a new cycle crank configuration that effectively allows the pedals to move independently throughout the duty cycle, on indices of endurance cycling performance in trained cyclists. Ten cyclists (5 Rotor users and 5 non-users; age (mean +/- SD): 22 +/- 5 y; VO(2)max: 69.5 +/- 5.1 mL x kg(-1) x min(-1)) volunteered to participate in the study. On four separate days, the subjects performed four cycle-ergometer tests, i.e. two incremental tests and two 20-min tests. An imposed crank rate of 75 rev x min(-1) was used during all tests. The incremental protocol started at 112.5 W, and the power output was increased by 37.5 W every 3 min until volitional exhaustion. The 20-min tests were performed at a fixed power output equivalent to 80% of the highest power output that the cyclists maintained for a complete 3-min period during incremental tests. Both types of tests were performed with the conventional crank system and the Rotor following a counter-balanced, cross-over design. Gas exchange parameters were measured in all the tests and blood lactate was determined at the end of each 3-min period (incremental tests) and at the end of the 20-min tests. A three factor (pedalling system used during the tests x habitual pedalling system x power output [incremental tests] or time [20-min tests]) ANOVA with repeated measures on power output (incremental tests) or time (20-min tests) was used to analyse several indices of performance, e.g. peak power output, VO(2)max, lactate threshold, onset of blood lactate accumulation, economy, delta, and gross efficiency. No differences (p > 0.05) were found between the Rotor and conventional systems for any of the aforementioned variables. It seems that the theoretical advantage brought about by the Rotor system, i.e. improved contra-lateral cooperation of both legs, would be minimized in trained cyclists. Although field studies are needed to assess the possible implications, in terms of actual racing, of the new system, commonly used indicators of endurance cycling performance do not seem to be improved with the Rotor in trained cyclists. [ABSTRACT FROM AUTHOR]

We report two-dimensional near-field imaging experiments of the 11.9-nm Sn X-ray laser that were performed with a set of novel Mo/Y multilayer mirrors having reflectivities of up to ∼40% at normal and at 45° incidence. Second-moment analysis of the X-ray laser emission was used to determine values of the X-ray beam propagation factor M2 for a range of irradiation parameters. The results reveal a reduction of M2 with increasing prepulse intensity. The spatial size of the output is a factor of ∼2 smaller than previously measured for the 14.7-nm Pd X-ray laser, while the distance of the X-ray emission with respect to the target surface remains roughly the same. [ABSTRACT FROM AUTHOR]

Investigates the heart responses of older male orienteers. Analysis of covariance, with age as a covariate and Pearson product-moment correlation coefficients; Lack of association between participants' maximal heart rates and age.

Presents various topics related to physiology. Effects of two respiratory warm-ups on respiratory muscle strength and performance in age-group swimmers; Details of heart rate responses of women during competitive orienteering; Discussion on menstrual cycle and immune status.

The aim of this study was to assess the effects of the age and sex of the competitor on orienteering speed during competitive events. The results of the fastest three male and fastest three female competitors in each 5-year age band (21-79 years), from four national orienteering events, were analysed. The data for age and orienteering speed were log-transformed and regression analyses were conducted to determine the relationships between age and sex and orienteering speed. For comparison, data for the fastest Great Britain finisher in the 10,000-m track and 10-km cross-country events for age groups 40-69 years at the World Masters Championships were also analysed. The results showed that, before the age of 40 years, there was no substantial slowing in orienteering speed for males (0.5-4.2% per decade) but a moderate decline (4.7-10.0% per decade) for females. After the age of 45 years, the orienteering speed of males and females slowed by 13 ± 2% and 16 ± 4% per decade (mean ±s), respectively, until around the age of 69, after which the deterioration was accentuated. The orienteering speed of the females was 81 ± 4, 74 ± 6 and 69 ± 7% that of the males at ages 21, 45 and 65 years, respectively. The magnitudes of the age-related slowing of orienteering speed and of the difference in orienteering speed between males and females aged 45 years and over were greater than those reported for the other endurance running events. This may reflect the physical demands of running in orienteering terrain, tactical and cognitive aspects of the sport, or sociocultural aspects of the participating population. [ABSTRACT FROM AUTHOR]

This study examined the effect of carbohydrate ingestion on metabolic and performance-related responses during and after a simulated 1 h cycling time trial. Eight trained male cyclists (VO[sub 2] peak = 66.5 ml kg[sup -1] min[sup -1]) rode their own bicycles mounted on a windload simulator to imitate real riding conditions. At a self-selected maximal pace, the cyclists performed two 1 h rides (separated by 7 days) and were fed either an 8% carbohydrate or placebo solution. The beverages were administered 25 min before (4.5 ml kg[sup -1]) and at the end (4.5 ml kg[sup -1]) of the ride. With carbohydrate feeding, plasma glucose tended (P = 0.21) to rise before the time trial. Compared with rest, the plasma glucose concentration decreased significantly (P < 0.05) at the end of both rides, with no statistically significant difference being observed between treatments. Thereafter, plasma glucose increased significantly (P < 0.05) at 15 and 30 min into recovery, and was significantly higher at 30 min during the carbohydrate trial compared with the placebo trial. No significant changes in plasma free fatty acids were observed during the ride. However, a significant increase (P < 0.05) in free fatty acids was found at 15 and 30 min into recovery, with no difference between trials. Mean power output was significantly (P < 0.05) greater during the carbohydrate compared with the placebo trial (mean - S.E.: 277-3 and 269-3 W, respectively). The greater distance covered in the carbohydrate compared with the placebo trial (41.5-1.06 and 41.0-1.06 km, respectively; P < 0.05) was equivalent to a 44 s improvement. We conclude that pre-exercise carbohydrate ingestion significantly increases endurance performance in trained cyclists during a 1 h simulated time trial. Although the mechanism for this enhancement in performance with carbohydrate ingestion cannot be surmised from the present results, it could be related to a higher rate of carbohydrate oxidation, or to favourable effects of carbohydrate ingestion on the central component of fatigue. [ABSTRACT FROM AUTHOR]

Coulomb effects in an extreme ultraviolet laser-induced photoelectron bunch for spectroscopy were investigated computationally. Post-photoemission alteration of the trajectory, due to Coulombic interactions, hampers an accurate angle-resolved photoelectron spectroscopy. Simulations however demonstrated that operation in the redundant-population regime produces a drag-confined bunch, detached from a boundary sheath that experiences losses. Drastic reduction in the photoelectron density can loosen bunch-confinement and proportionally increase the boundary losses. Our simulations led to a critical number of photoelectrons per spot size equal to 1.5×104 e-/mm2. [ABSTRACT FROM AUTHOR]

A novel type of ion spectrometer for laser-produced plasma diagnostics is described. The Thomson parabola configuration is used to separate the expanding plasma ions according to their different charge-to-mass ratios. One particular ion species is subsequently collected by a parabola-shaped charge collector. In this way ion velocity distributions of a single charge-to-mass ratio are obtained through simple time-of-flight analysis. Measured ion energies can be as low as 1 keV per nucleon. [ABSTRACT FROM AUTHOR]

Cylindrical cavity targets with inner diameters between 200 and 300 μm have been irradiated with 4 J, 80 ps, Nd:glass laser pulses through a 100-μm-wide longitudinal slit. From the spatially resolved temporal and spectral behavior of the x-ray emission along the axis, data on temperature and density of the expanding primary and secondary plasmas and of the region of collision have been obtained. [ABSTRACT FROM AUTHOR]

An optical and an x-ray streak camera have been synchronized by driving the deflection plates of both cameras from the same ramp generator. The relative timing of the two cameras was calibrated by running UV light onto the x-ray streak camera. The x-ray streak camera was then used to measure the time of the x-ray emission from a laser plasma with respect to the laser pulse. [ABSTRACT FROM AUTHOR]