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N M Cole

Publications and source records attributed to N M Cole.

7 recordsLinked to original sources
PubMed1990

Muscle sounds are emitted at the resonant frequencies of skeletal muscle.

The changes in mechanical resonant frequency of whole muscles during twitch and tetanic contractions were compared to changes in frequency components of the pressure wave produced by muscles during contraction. Resonant frequencies were determined by imposing sinusoidal length changes on a muscle and observing transverse standing waves when the frequency of length change matched the muscle's resonant frequency or a harmonic of the resonant frequency. Acoustic signal instantaneous frequency spectrums were calculated using time-frequency transformations including the Wigner transform and the exponential distribution. During a tetanic muscle contraction, the peak instantaneous frequency initially increased and then became constant as the force plateau was reached. The resonant frequencies determined during the force plateau and during relaxation spanned the same range as the peak instantaneous frequency of the acoustic signal. These results suggest that the acoustic signal may be useful as a non-invasive monitor of muscle resonant frequency during contraction.

Animals↗
PubMed1988

Fluid mechanics of muscle vibrations.

The pressure field produced by an isometrically contracting frog gastrocnemius muscle is described by the fluid mechanics equations for a vibrating sphere. The equations predict a pressure amplitude that is proportional to the lateral acceleration of the muscle, inversely proportional to the square of the distance from the muscle, and cosinusoidally related to the major axis of lateral movement. The predictions are confirmed by experiments that measure the pressure amplitude distribution and by photographs of muscle movement during contraction. The lateral movement of muscle has the appearance of an oscillating system response to a step function input--the oscillation may be at the resonant frequency of the muscle and therefore may provide a means to measure muscle stiffness without actually touching the muscle.

Animals↗
PubMed1988

Informed consent: considerations in aesthetic and reconstructive surgery of the breast.

A definite standard of care exists for establishing informed consent. The plastic surgeon has an obligation to meet these requirements with each patient undergoing surgery. The difficulties of adequately informing have been described and suggestions made for supplementing the consultation with a variety of adjuncts. The goal is to inform and use whatever methods are effective in achieving this goal. Establishing valid informed consent will not prevent all medical liability claims. Despite the most conscientious efforts to inform, some claims will still occur alleging "lack of informed consent." The surgeon must then prove that sufficient information was provided. However, many patients who feel that the surgeon made every effort to inform and felt that the surgeon was honest, conscientious, concerned, and thorough will be less inclined to generate claims even in the face of unsatisfactory results or untoward complications. Informed consent is the patient's right and the surgeon's obligation. The medicolegal benefits from fully informing are tangible and one of the most effective methods to reduce claims and modify risk.

Breast↗