An Assistive Mechanical Device for Mandibular Reconstruction

Summary Aim: Determination of the range of regional blood flow and fluoride influx during normal incorporation of revascularized fibula grafts used for mandibular reconstruction. Evaluation, if healing complications are preceded by typical deviations of these parameters from the normal range. Assessment of the potential influence of using “scaled population-derived” instead of “individually measured” input functions in quantitative analysis. Methods: Dynamic F-l 8-PET images and arterialized venous blood samples were obtained in 11 patients early and late after surgery. Based on kinetic modeling regional blood flow (K1) and fluoride influx (Kmlf) were determined. Results: In uncomplicated cases, early postoperative graft K1 - but not Kmlf -exceeded that of vertebrae as reference region. Kmn values obtained in graft necrosis (n = 2) were below the ranges of values observed in uncomplicated healing (0.01 13-0.0745 ml/min/ml) as well as that of the reference region (0.0154-0.0748). Knf values in mobile non-union were in the lower range - and those in rigid non-union in the upper range of values obtained in stable union (0.021 1-0.0694). If scaled population-derived instead of measured input functions were used for quantification, mean deviations of 23 ± 17% in K1 and 12 ± 16% in Kmlf were observed. Conclusions: Normal healing of predominantly cortical bone transplants is characterized by relatively low osteoblastic activity together with increased perfusion. It may be anticipated that transplant necrosis can be identified by showing markedly reduced F− influx. In case that measured input functions are not available, quantification with scaled population-derived input functions is appropriate if expected differences in quantitative parameters exceed 70%.

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DESIGN OF A MECHANICAL DEVICE FOR REDUCING NOISE AND ISSUANCE OF GAS AND PARTICLES FOR DIESEL ENGINES FROM AN ENERGY GENERATING ENGINE

10.26678/abcm.encit2018.cit18-0835 ◽

2018 ◽

Author(s):

Herivaldo Pascoal ◽

Domingos Sávio Tavares Mendes Junior ◽

ANTONILSON CONCEIÇÃO ◽

Yves Bandeira ◽

Carlisson Azevedo ◽

...

Keyword(s):

Diesel Engines ◽

Mechanical Device

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Sliding Mode Control of an Actuated Knee Joint Orthosis

Current Signal Transduction Therapy ◽

10.2174/1574362415999210104223820 ◽

2021 ◽

Vol 15 ◽

Author(s):

Imen Saidi ◽

Asma Hammami

Keyword(s):

Sliding Mode Control ◽

Lower Limb ◽

Sliding Mode ◽

Position Tracking ◽

Sliding Mode Controller ◽

Mechanical Device ◽

Tracking Errors ◽

Mode Control ◽

Speed Tracking ◽

Human Morphology

Introduction: In this paper, a robust sliding mode controller is developed to control an orthosis used for rehabilitation of lower limb. Materials and Methods: The orthosis is defined as a mechanical device intended to physically assist a human subject for the realization of his movements. It should be adapted to the human morphology, interacting in harmony with its movements, and providing the necessary efforts along the limbs to which it is attached. Results: The application of the sliding mode control to the Shank-orthosis system shows satisfactory dynamic response and tracking performances. Conclusion: In fact, position tracking and speed tracking errors are very small. The sliding mode controller effectively absorbs disturbance and parametric variations, hence the efficiency and robustness of our applied control.

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