Difficulties of radiological diagnosis оf small breast cancers

Introduction. Breast cancer in the structure of malignancies in women takes the 1st place. There has been an annual increase in morbidity, including due to improvements in diagnostic interventions and screening. Mammography and ultrasound of the breasts is mandatory when diagnosing breast cancer. The difficulties of diagnosis are revealed in small tumorsВведение. Рак молочной железы (РМЖ) в структуре злокачественных новообразований (ЗНО) у женщин занимает первое место. Отмечается ежегодный прирост заболеваемости, в том числе из-за усовершенствования диагностических мероприятий и скрининга. Маммография и ультразвуковое исследование молочных желез является обязательным при постановке диагноза РМЖ. Сложности диагностики выявляются при опухолях малых размеров

Corrélations entre les propriétés mécaniques des fibres de lin et celles des composites dérivés

Des composites unidirectionnels contenant entre 10 et 40 % de fibres de lin en volume ont été fabriqués par moulage par compression. Leurs propriétés mécaniques en traction et en flambement sont discutées en fonction de celles des fibres et de la matrice. L’évolution quasi linéaire des propriétés des composites avec le taux volumique de fibres a été extrapolée à une teneur en renfort de 100 % afin d’estimer les propriétés mécaniques des faisceaux de fibres : les calculs donnent une contrainte à rupture de ces faisceaux de l’ordre de 500 MPa et un module d’environ 30 GPa, valeurs deux fois plus faibles que celles mesurées par traction sur des fibres élémentaires. De meilleures propriétés mécaniques pourraient être obtenues à travers une plus grande maîtrise de la division des faisceaux de fibres

Microstructured optical fiber Bragg grating as an internal three-dimensional strain sensor for composite laminates

International audienceIn this article, we study the possibility to use a pair of specifically designed microstructured optical fiber Bragg gratings (MOFBGs) as a multi-component strain sensor when embedded within composite materials. The dependence on the orientation of the transverse sensitivity of the MOFBGs is exploited to build a sensing device able to measure the strain field along the three principal mechanical directions of a laminate composite. We developed an analytical and numerical model of such a sensor and benchmarked it with experiments performed on laminated composite coupons equipped with this sensor. We report on a theoretical strain resolution of about 5 μ in the transverse directions of the composite material, which is a six-fold improvement over results reported in literature. © 2015 IOP Publishing Ltd

Embedded fiber bragg gratings in photonic crystal fiber for cure cycle monitoring of carbon fiber-reinforced polymer materials

We report on the use of a fiber Bragg grating (FBG) based sensor written in a photonic crystal fiber (PCF) to monitor the cure cycle of composite materials. The PCF under study has been specifically designed to feature a high phase modal birefringence sensitivity to transverse strain and a very low sensitivity to temperature. We exploit these particular properties to measure strain inside a composite material in the out-of-plane direction. The embedded FBG sensor has been calibrated for transverse and axial strain as well as for temperature changes. These FBGs have then been used as embedded sensors during the manufacturing of a composite material in order to monitor how strain develops inside the composite during the cure cycle. We show that our sensors allow gaining insight in the composite cure cycle in a way that would be very difficult to achieve with any other sensor technology