Finite element (FE) modeling and multibody dynamics have traditionally been applied separately to the domains of tissue mechanics and musculoskeletal movements, respectively. Simultaneous simulation of both domains is needed when interactions between tissue and movement are of interest, but this has remained largely impractical due to the high computational cost. Here we present a method for th...

The short-term effects of whole-body vibration as a novel method of somatosensory stimulation on postural control were investigated in 23 chronic stroke patients. While standing on a commercial platform, patients received 30-Hz oscillations at 3 mm of amplitude in the frontal plane. Balance was assessed four times at 45-min intervals with a dual-plate force platform, while quietly standing with...

PURPOSE To evaluate tear film stability and optical aberrations in eyes wearing plano Lotrafilcon B contact lenses (CL). METHODS Tear Deformation Time (TDT) and aberrometric parameters were assessed in 86 normal emmetropic eyes before and 6 h after wearing CL. RESULT A statistically significant decrease in TDT and increase in root mean square (RMS) values of higher order aberrations (HOA) w...

For this investigation, we studied the effects of extremely low frequency pulse electromagnetic fields (ELF-PEMF) on the human cardiac signal. Electrocardiograms (ECGs) of 22 healthy volunteers before and after a short duration of ELF-PEMF exposure were recorded. The experiment was conducted under single-blind conditions. The root mean square (RMS) value of the recorded data was considered as c...

BACKGROUND Precise measurement of the QT interval is often hampered by difficulty determining the end of the low amplitude T wave. Root mean square electrocardiography (RMS ECG) provides a novel alternative measure of ventricular repolarization. Experimental data have shown that the interval between the RMS ECG QRS and T wave peaks (RTPK) closely reflects the mean ventricular action potential d...

[1] Atmospheric density accounts for the largest source of error for predicting low-Earth orbiting satellite positions. Relevant applications include catalog maintenance, collision avoidance, and mission design. In this paper we quantify density model errors due to density variability at submodel grid spatial scales. Densities in the 370--450 km height region inferred from accelerometer measure...

Like glaciers throughout the world, tropical glaciers in the northern Andes have retreated during the last century. In this study, the retreat of Andean glaciers in Colombian and Venezuela has been mapped from Landsat and ASTER images acquired between 1984 and 2004. Glacier retreat has been mapped for three glaciated regions in Columbia, the Sierra Nevada de Santa Marta, the Sierra Nevada del C...

A long-term (1983–2000) global dataset of Earth’s surface daily-integrated UV exposure was developed from a combination of ISCCP-D1 3 h reflectance measurements (in order to resolve the diurnal variation of cloud conditions) and TOMS total ozone amount. The inversion algorithm developed in our previous study was employed with modifications addressing the conversion of visible reflectance to UV ...

Synchronous sampling allows alternating current (AC) quantities, such as the root mean square (RMS) values of voltage and power, to be determined with very low uncertainties (on the order of a few parts of 10 [1]). In this a new mathematical expression for estimating measurement uncertainties in nonideal synchronization with fundamental frequency AC signals is presented. The obtained results we...

In this paper, a 4-bit digital step attenuator using 0.25 μm GaN HEMT technology for wideband radar systems is presented. A switched-path topology with resistive T-type attenuators and double-pole double-throw (DPDT) switches was used to achieve both low insertion loss phase/amplitude error. The measured of the reference state 2.8–8.3 dB at DC-12 GHz. input output return are less than 12 An att...