The purpose of this study was to develop an imageless (without preoperative computerized tomography (CT) scans or intraoperative fluoroscopy) computer navigation system for total hip replacement. One-hundred and ninety-five hips were operated with imageless computer navigation. Eighty-five hips were operated prior to obtaining precise results, with precision refined in the subsequent 110 hips. ...

An optical tilt sensor was developed and its performance was investigated. The tilt sensor set-up consisted of a laser light source, lenses and an image sensor. A precision reference tilt sensor was also installed on the same stage, and the measurement results of tilt angles using the optical and reference tilt sensors were correlated. The correlation coefficient (R-value) obtained under ideal ...

BACKGROUND AND PURPOSE Cerebrovascular autoregulation has been described with a phase lead of cerebral blood flow preceding changes in cerebral perfusion pressure (CPP), but there has been less focus on the effect of CPP on cerebral vascular resistance. We investigated these relations during spontaneous fluctuations (control) and repeated head-up tilt. METHODS Eight healthy adults were studie...

Measurements of the circular polarization of Balmer-u radiation emitted by excited hydrogen atoms, following the transmission of (20—50)-keV protons through thin, tilted amorphous carbon foils, exhibit markedly unexpected behavior as a function of exposure of the foil to the proton beam. Specifically, the circular polarization changes from an initially well understood tilt-angle dependence to a...

Cardiovascular responses to orthostatic stress induced by tilt maneuver were measured in seven subjects, before and after a 14 days head-down tilt bed rest (HDTBR). The response of the autonomic nervous system was evaluated through the analysis of the heart rate (HRV) and arterial blood pressure (ABP) variability. Spectral components, entropy indices and the Lempel Ziv Complexity were measured ...

How does the brain calculate the spatial orientation of the head relative to gravity? Psychophysical measurements are critical to investigate this question, but such measurements have been limited to humans. In non-human primates, behavioral measures have focused on vestibular-mediated eye movements, which do not reflect percepts of head orientation. We have therefore developed a method to meas...

We compare the latest cosmic microwave background data with theoretical predictions including correlated adiabatic and cold dark matter (CDM) isocurvature perturbations with a simple power-law dependence. We find that there is a degeneracy between the amplitude of correlated isocurvature perturbations and the spectral tilt. A negative (red) tilt is found to be compatible with a larger isocurvat...

Spectral tilt has been suggested to be a correlate of prominence in speech, although several studies have not replicated this empirically. This may be partially due to the lack of a standard method for tilt estimation from speech, rendering interpretations and comparisons between studies difficult. In addition, little is known about the performance of tilt estimators for prominence detection in...

Recent measurements by the H1 experiment of the inclusive charm and beauty cross sections in deep inelastic ep scattering at HERA are presented. The data were collected in the years 2006 and 2007 corresponding to an integrated luminosity of 189 pb −1. The numbers of charm and beauty events are determined using variables reconstructed by the H1 vertex detector. The measurement of the inclusive c...

Five commonly used methods for determining the onset of voicing of syllable-initial stop consonants were compared. The speech and glottal activity of 16 native speakers of Cantonese with normal voice quality were investigated during the production of consonant vowel (CV) syllables in Cantonese. Syllables consisted of the initial consonants /ph/, /th/, /kh/, /p/, /t/, and /k/ followed by the vow...