Improving the assay-gravimetric method for determining the content of noble metals

The study considers the current state and problems of analytical control as the most important component of all stages of technology and production of noble metals. Based on the analysis carried out, a universal method for measuring the mass fraction of gold and silver in ores, products of their enrichment and metallurgical processing by the assay-gravimetric method was improved, and the optimal parameters for determining gold and silver were determined

Percolation in Models of Thin Film Depositions

We have studied the percolation behaviour of deposits for different (2+1)-dimensional models of surface layer formation. The mixed model of deposition was used, where particles were deposited selectively according to the random (RD) and ballistic (BD) deposition rules. In the mixed one-component models with deposition of only conducting particles, the mean height of the percolation layer (measured in monolayers) grows continuously from 0.89832 for the pure RD model to 2.605 for the pure RD model, but the percolation transition belong to the same universality class, as in the 2- dimensional random percolation problem. In two- component models with deposition of conducting and isolating particles, the percolation layer height approaches infinity as concentration of the isolating particles becomes higher than some critical value. The crossover from 2d to 3d percolation was observed with increase of the percolation layer height.Comment: 4 pages, 5 figure

Gravitational Ionization: A Chaotic Net in the Kepler System

The long term nonlinear dynamics of a Keplerian binary system under the combined influences of gravitational radiation damping and external tidal perturbations is analyzed. Gravitational radiation reaction leads the binary system towards eventual collapse, while the external periodic perturbations could lead to the ionization of the system via Arnold diffusion. When these two opposing tendencies nearly balance each other, interesting chaotic behavior occurs that is briefly studied in this paper. It is possible to show that periodic orbits can exist in this system for sufficiently small damping. Moreover, we employ the method of averaging to investigate the phenomenon of capture into resonance.Comment: REVTEX Style, Submitte

Проблемы и достижения генной терапии муковисцидоза

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Experiense of treatment with a growth hormone receptor antagonist in patients with hereditary form of acromegaly: clinical cases

Acromegaly is a severe neuroendocrine disease caused by chronic excessive production of somatotropic hormone (STH), characterized by specific changes in appearance, metabolic disorders. In 95% of cases, the cause of pathology is STH-producing pituitary adenomas. The priority method of treatment for acromegaly is transnasal transsphenoidal adenomectomy. If it is impossible to carry out neurosurgical intervention, in order to prevent the progression of the disease and the development of complications, patients are recommended drug therapy with long-acting somatostatin analogues, and if their effectiveness is low, additional radiation therapy may be applied to the neoplasm area. The usage of a relatively new group of drugs, antagonists of STH receptors, namely Pegvisomant for the purpose of drug treatment of acromegaly demonstrates high efficacy even in cases of aggressive forms resistant to other types of treatment. In this article we present two clinical cases of hereditary acromegaly, when the initiation of Pegvisomant therapy led to the achievement of clinical and laboratory remission of acromegaly in patients with an aggressive form of the disease, accompanied by continued growth of residual neoplasm tissue and preservation of its secreting ability even after surgical interventions, radiatiotherapy and long-term drug treatment with somatostatin analogues. The results of the above clinical cases confirm the success of mono- or combined (in cases with continued growth of the neoplasm) therapy with a growth hormone receptor antagonist, Pegvisomant, especially in the case of aggressive acromegaly

ОСТРЫЕ КИШЕЧНЫЕ ИНФЕКЦИИ С ЛЕТАЛЬНЫМ ИСХОДОМ У ВЗРОСЛЫХ БОЛЬНЫХ В САНКТ-ПЕТЕРБУРГЕ: ДИНАМИКА ЭТИОЛОГИЧЕСКОЙ СТРУКТУРЫ И ХАРАКТЕРИСТИКА ТЕЧЕНИЯ

The paper suggests characteristics of the disease course in 193 adult acute diarrhea (AD) severe cases hospitalized in 2002-2004. Following the pathomorphological study records, the structures of AD cases hospitalized in 2002 - 2004 and in 2008-2010 has been compared. It is shown that adult AD severe cases are rather more than likely to have lethal outcome in case of comorbidity and hospital admission later than on the 3rd disease day. In the period of dysentery high-incidence level in structure of AD with lethal outcome, shigellosis (including that diagnosed morphologically) dominates, as compared to the period of dysentery low-incidence level when the burden of salmonellosis and AD of unknown etiology has been seen to grow.Охарактеризовано течение тяжелой формы ОКИ у 193 госпитализированных в 2002-2004 г. взрослых пациентов. По протоколам патоморфологических исследований сопоставлена структура острых диарей с летальным исходом, диагностированных в стационаре за периоды 2002-2004 и 2008-2010 гг. Показано, что у взрослых больных тяжелое течение острой диареи значительно чаще заканчивается летальным исходом при наличии сопутствующей патологии и поступлении в стационар позднее 3-го дня заболевания. В структуре ОКИ с летальным исходом в период эпидемиологического неблагополучия по дизентерии преобладает шигеллез, в том числе диагностированный гистоморфологически, а в период эпидемиологического благополучия существенной становится доля сальмонеллеза и ОКИНЭ, что диктует необходимость совершенствования тактики выявления этиопатогенов с целью своевременной и адекватной терапии

Long action somatostatin analogues in patients with TSH-secreted pituitary adenomas: treatment experience

Thyrotoxicosis, which characteristics are increased excitability, emotional lability, tachycardia episodes, increasing of free fractions of tetraiodothyronine (T4) and triiodothyronine (T3) is one of the most common endocrinological syndromes. However, during the interpretation of thyroid status it is very important to take into account the possibility that a patient has TSH-secreting pituitary adenoma. Timely diagnosis of TSH-secreting adenomas plays prominent role in guiding the treatment course since it is associated with an improvement of long-term prognosis and an increase of the patient’s total life expectancy. Needed to underline that in some patients with TSH-secreting adenomas manifestations of the other pituitary hormones hypersecretion (first of all — somatotropin and prolactin) come to the fore, that lead to the development of acromegaly and hyperprolactinemia accordingly. Our work basing on two clinical cases presents main principles of diagnosis and specific clinical manifestations of TSH-secreting pituitary adenomas and demonstrates efficacy of somatostatin analogues in the treatment of this pathology

Orbital effects of a monochromatic plane gravitational wave with ultra-low frequency incident on a gravitationally bound two-body system

We analytically compute the long-term orbital variations of a test particle orbiting a central body acted upon by an incident monochromatic plane gravitational wave. We assume that the characteristic size of the perturbed two-body system is much smaller than the wavelength of the wave. Moreover, we also suppose that the wave's frequency is much smaller than the particle's orbital one. We make neither a priori assumptions about the direction of the wavevector nor on the orbital geometry of the planet. We find that, while the semi-major axis is left unaffected, the eccentricity, the inclination, the longitude of the ascending node, the longitude of pericenter and the mean anomaly undergo non-vanishing long-term changes. They are not secular trends because of the slow modulation introduced by the tidal matrix coefficients and by the orbital elements themselves. They could be useful to indepenedently constrain the ultra-low frequency waves which may have been indirectly detected in the BICEP2 experiment. Our calculation holds, in general, for any gravitationally bound two-body system whose characteristic frequency is much larger than the frequency of the external wave. It is also valid for a generic perturbation of tidal type with constant coefficients over timescales of the order of the orbital period of the perturbed particle.Comment: LaTex2e, 24 pages, no figures, no tables. Changes suggested by the referees include