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The Doppler signal of mitral valve is a biomedical signals and it is acquired by Doppler ultrasound device from mitral valve of hearth. It contains useful information about mitral valve and it can be used to diagnose mitral valve diseases by doctors. However, biomedical signal might be contaminated with noise or disruptive interference. In literature, different approaches have been introduced to remove the noise or interference from biomedical signal, but adaptive filtering is most popular technique for noise filtering. Therefore, a novel adaptive noise cancellation techniques based FIR digital filter was proposed using artificial bee colony algorithm (ABC) and it is employed for the noise reduction on noisy mitral valve Doppler signal. So, the meaningful data about mitral valve was saved to diagnose mitral valve diseases using denoising approach. Then, this novel approach was compared with the other methods suggested in literature such as recursive least square (RLS) algorithm or discrete wavelet transform (DWT). Also, to demonstrate the efficiency, different digital filter order and noise cases were used suggested in literature. [ABSTRACT FROM AUTHOR]

Summary: Background: Defect reconstruction according to the free-style concept applied to perforator flaps allows flap harvesting in any anatomical region where an audible Doppler signal of a perforator is detected. We report the results of a study in which local perforator flaps were selected for reconstruction in different anatomical areas and were harvested using the free-style concept. Methods: During a 2-year period, defect coverage was carried out in 21 patients (n =21) in the following anatomical areas: cervical (n =3), sternal/parasternal (n =4), axillary (n =2), tibial (n =5), trochanteric (n =2) and sacral/gluteal (n =5). The mean age of patients (15 male and six female) was 57.8 years. Flap selection was based solely on preoperative Doppler mapping in areas adjacent to soft-tissue defects. The mean follow-up period was 1 year. Results: All flaps survived, demonstrating postoperatively acceptable aesthetic results with good patient satisfaction. The donor sites were closed primarily in 17 patients; four patients required skin grafting. Two patients required surgical revision due to flap-margin dehiscence. There was no loss of function at donor sites. Increased flap mobility could be achieved through extended perforator dissection. One perforator-based flaps offered the widest arc of rotation serving as propeller flaps. If more than one perforator vessel was preserved, flap mobility was limited, but still allowed sufficient flap movement either as a rotation or advancement flap or as a combination of both. A classification is proposed according to the number of perforator vessels preserved and to the type of flap movement. Conclusions: The concept of free-style local perforator flaps represents a safe, versatile and reliable surgical procedure. It not only offers a greater freedom in flap selection but also provides good aesthetic results. The classification proposed might aid in the decision-making process involved in order to achieve adequate results with this procedure. [Copyright &y& Elsevier]