Growing evidence supports a 1972 proposal that dynamic tension strains of a ligament above a threshold range, but below its ultimate strength, would make its cells synthesize more collagen to thicken and strengthen it. If so, when that strengthening reduced later strains to the bottom of that threshold range this "diametric modeling" would stop. A) Such a mechanism must create a "strength-safet...

During moderate exercise breathing a low inspired O(2) fraction (F(I)O(2)), arterial O(2) desaturation may depend on the fitness level. Seven trained (TM) and seven untrained men (UTM) cycled in normoxia and in hypoxia (F(I)O(2)=0.187, 0.173, 0.154, 0.13 and 0.117). We compared TM and UTM at submaximal intensities below the ventilatory threshold. Ventilatory variables were monitored and arteria...

Lower thresholds and smaller stimulus currents may allow for the use of smaller cochlear implant stimulus electrodes and potentially more channels of stimulation within a given cochlea region. With high (2kpps) compared to low (125pps) pulse rate stimuli, inferior colliculus (IC) units have a significantly lower stimulus threshold [l]. The provision of a background "spontaneous" stimuli may pro...

The two-dimensional momentum distributions of high-energy photoelectrons generated in the above-threshold ionization of atoms by intense laser pulses are analysed as resulting from the elastic backscattering of laser-induced returning electrons. Using this quantitative rescattering theory, we show that the returning electron wave packets are entirely determined by the properties of the laser pu...

We report on the direct observation of an attosecond pulse train with a mode-resolved autocorrelation technique. The chirp among the three harmonic fields is specified by analyzing two-photon above-threshold ionization spectra of electrons, resulting in a pulse duration that should be shorter than 450 as, which is, to our knowledge, the first determination of the chirp in the attosecond pulse t...

In order to reduce pacing current threshold in transesophageal stimulation, a novel multichannel transesophageal pacemaker and multichannel esophageal lead has been developed. Three different approaches to reduce pacing current threshold were clinically studied. Precise positioning of the pacing dipole allowed reduction of pacing current threshold on average by 20% over the standard bipolar tra...

The largest voluntary loads on bones come from muscles. To adapt bone strength and mass to them, special strain threshold ranges determine where modeling adds and strengthens bone, and where remodeling conserves or removes it, just as different thermostat settings control the heating and cooling systems in a house. If estrogen lowers the remodeling threshold, two things should occur. First, at ...

We investigated the properties of pulse propagation on nonlinear traveling-wave field effect transistors (TWFET) in order to develop a method for generating short electrical pulses. We considered the case where a decreasing voltage pulse is applied to the gate line and an increasing one is simultaneously applied to the drain line. By properly designing the top and bottom levels of the applied p...

Spatial localization of flashed stimuli across saccades shows transient distortions of perceived position: Stimuli appear shifted in saccade direction and compressed towards the saccade target. The strength and spatial pattern of this mislocalization is influenced by contrast, duration, and spatial and temporal arrangement of stimuli and background. Because mislocalization of stimuli on a backg...

We report here a possible detection of weak pulsed radio emission from Geminga on 1997 June 19, as evident from the observed power spectrum and the folded pulse pro®le. The observations were made with the Rajkot radio telescope at 103 MHz. Our observations show the presence of an average pulse strength at about 1 Jy level, with a pulse period of 237.10 ms and an interpulse of comparable intensi...