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Experimental method of temperature and strain discrimination with fiber Bragg gratings (FBGs) sensors embedded in carbon fiber-reinforced plastic is proposed. The method is based on two-fiber technique, when two FBGs inscribed in different fibers with different sensitivities to strain and/or temperature are placed close to each other and act as a single sensing element. The nonlinear polynomial approximation of Bragg wavelength shift as a function of temperature and strain is presented for this method. The FBGs were inscribed with femtosecond laser by point-by-point inscription technique through polymer cladding of the fiber. The comparison of linear and nonlinear approximation accuracies for array of embedded sensors is performed. It is shown that the use of nonlinear approximation gives 1.5–2 times better accuracy. The obtained accuracies of temperature and strain measurements are 2.6–3.8°C and 50–83 μεin temperature and strain range of 30–120°C and 0–400 με, respectively.

A total of 182 patients (95 men and 87 women) aged 15-49 years with insulin-dependent diabetes mellitus were treated using argon laser coagulation. Late results of laser therapy were followed up for 6 months to 3 years. In the patients with nonproliferative diabetic retinopathy (DR) on the fundus oculi the improvement consisted in partial resolution of solid exudative foci and retinal hemorrhages in 20%o of cases. In patients with preproliferative DR, soft exudative foci partially resolved and the number of retinal hemorrhages and microaneurysms decreased in 17%o of cases. In patients with proliferative DR, regressive development of proliferative tissue, desolation of newly formed vessels, and resolution of preretinal hemorrhages were observed in 13.9%o of cases. Stabilization for 3 years was attained in 75%) of patients with nonproliferative and proliferative and in 72.5%o of those with preproliferative DR.

A total of 185 children (93 boys and 92 girls) aged 6 months to 15 years and disease duration of 1 to 13 years, residents of different regions of Russia, were examined. Pathological changes of the retina caused by diabetes were detected on the fundus oculi of 56 (30.3%) children. In 42 (22.7%)) of these, the initial changes (solitary retinal hemorrhages, microaneurysms) and in 14 (7.6%)) more pronounced micro- vascular pathological changes typical of nonproliferative diabetic retinopathy were detected, in 2 patients - the proliferative stage. Later argon coagulation of the retina was carried out in 10 patients with nonproliferative diabetic retinopathy and in 2 with proliferative diabetic retinopathy. The initial stages of nonproliferative and proliferative diabetic retinopathy are an indication for laser coagulation in children. The status of 6 (50%) children improved in remote periods (6-24 months) after laser coagulation: hemorrhages resolved and microaneurysms decreased; in 4 (33.3%) children the process was stabilized. Deterioration was observed in 2 (16. 7%o) children with nonproliferative and proliferative diabetic retinopathy.