Modulation Instability of Ultrashort Pulses in Quadratic Nonlinear Media beyond the Slowly Varying Envelope Approximation

We report a modulational instability (MI) analysis of a mathematical model appropriate for ultrashort pulses in cascaded quadratic-cubic nonlinear media beyond the so-called slowly varying envelope approximation. Theoretically predicted MI properties are found to be in good agreement with numerical simulation. The study shows the possibility of controlling the generation of MI and formation of solitons in a cascaded quadratic-cubic media in the few cycle regimes. We also find that stable propagation of soliton-like few-cycle pulses in the medium is subject to the fulfilment of the modulation instability criteria

Pathogenetic treatment of mastopathy and prevention of breast cancer

Pathogenetic treatment of mastopathy and prevention&nbsp;of breast cancer V.G. Bespalov N.N. Petrov National Medical Research Center of Oncology of the Russian Ministry of Health, Saint Petersburg, Russian Federation The review article discusses the relationship between an etiology and risk factors for benign breast disease (BBD) and breast cancer (BC), the pathogenesis of BBD due to an increased risk of BC, a risk assessment of BC in patients with BBD; pathogenetic treatment of BBD, aimed at preventing BC; an application of the drug Mamoclam® for the treatment of BBD and prevention of BC. BBD and BC have a common etiology and most risk factors are the same for both pathologies. Multiple risk factors disrupt the hormonal balance in a woman’s body, cause hyperestrogenism and epithelium hyperproliferation in the mammary tissue, which leads to the development of BBD, and in the presence of congenital or acquired gene damage, BBD increases the risk of BC. Crucial in assessing the risk degree of BC in patients with BBD is a morphological study of the mammary tissue obtained by biopsy. The risk of BC does not increase or is minimal with non-proliferative forms of BBD and increases significantly with proliferative BBD and precancerous lesions, such as atypical hyperplasia and carcinoma in situ. Mamoclam® is a non-hormonal drug containing organically bound iodine as an active substance. Mamoclam® is effective and safe drug for the pathogenetic treatment of BBD, with prolonged use reduces the risk of BC. Key words: benign breast disease, breast cancer, risk factors, etiology, pathogenesis, precancerous lesions, prevention, treatment of benign breast disease, Mamoclam. For citation: Bespalov V.G. Pathogenetic treatment of mastopathy and prevention of breast cancer. Russian Journal of Woman and Child Health. 2018;1(2):141–147.<br

Nondestructive monitoring of aircraft composites using terahertz radiation

In this paper we consider using the terahertz (THz) time domain spectroscopy (TDS) for non destructive testing and determining the chemical composition of the vanes and rotor-blade spars. A versatile terahertz spectrometer for reflection and transmission has been used for experiments. We consider the features of measured terahertz signal in temporal and spectral domains during propagation through and reflecting from various defects in investigated objects, such as voids and foliation. We discuss requirements are applicable to the setup and are necessary to produce an image of these defects, such as signal-to-noise ratio and a method for registration THz radiation. Obtained results indicated the prospects of the THz TDS method for the inspection of defects and determination of the particularities of chemical composition of aircraft parts