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The analytical relationship between the delivery-rate criterion of an axial flow impeller and the power criterion has been found using the angular momentum equation as a basis. This relationship was derived under the assumption of a constant field of tangential velocities along the height of a mixer. Based on the experimentally found velocity fields available in the literature, the equation for calculating the coefficient of proportionality between the delivery rate of a flow impeller and the circulation flow rate is obtained. The published experimental delivery rates and circulation flow rates of a flow impeller are compared with their calculated values found by the proposed equations.

A number of single-domain antibodies (nanobodies) obtained previously to major marker blood proteins were tested as tools to preprocess urine samples from patients with bladder cancer. Nanobody-based tools demonstrated unique possibilities for noninvasive diagnostic studies along with other conventional methods, such as electrophoresis and, in prospect, mass spectrometric analysis. A testing of 22 samples from bladder cancer patients showed that the development of bladder cancer is accompanied by an increase in the urine contents of major blood proteins, including those known as potential bladder cancer biomarkers. New nanobody-based immunosorbents allow both specific enrichment and specific removal of particular antigenic proteins and subproteomes associated with them from a biological fluid. The isolation of immune complexes from the urine of a particular patient is of particular interest. An initial study of the complexes showed not only increased contents of IgA and IgG at advanced stages of the disease, but also many other components, which provide potential biomarkers of the pathological process in a particular patient. It is intended to use the approaches proposed in this work in a future larger-scale study of urine samples from patients with bladder cancer at different stages of the disease in order to identify new promising biomarkers of bladder cancer.

The advantages of special smooth-wall apparatuses equipped with precession stirrers compared to typical process tanks equipped with the stiff shafts of stirrers have been shown. A one-dimensional mathematical model has been considered for describing the rotary velocity field and calculating the hydrodynamic loads used during the design of large-volume precession apparatuses for mixing ore pulps. The validity of the model has been confirmed experimentally using the literature data and a positive experience in the long-term operation of process tanks that are 50–1250 m3 in volume, which are designed for the dealkalization of high concentrations of ore suspensions of noble metals.

Prostate cancer (PC) is now one of the most common malignancies among men. Radical prostatectomy is the most commonly used therapy option for patients with localized PC. The appropriateness of surgical treatment for locally advanced and lymphogenic metastatic PC remains controversial, as the probability of non-radical intervention increases significantly and the risk for disease progression becomes higher. At the same time, interest in surgical treatment in patients with PC at high risk of progression, including those with lymphogenic metastases has recently increased greatly. There are more and more studies demonstrating improved survival rates in patients with high-risk PC, including those with distant metastases, who have undergone radical prostatectomy and lymphadenectomy compared with a cohort of patients who have received only drug therapy In addition to the studies evaluating the efficiency of neoadjuvant therapy before surgery in patients with localized or locally advanced high-risk PC, there are also investigations considering this option in PC patients with lymphogenic metastases. The paper gives the results of a clinical observation that shows the high efficiency of a multimodal approach with neoadjuvant chemohormonal therapy, followed by surgical treatment in a patient with lymphogenic metastatic PC.

Prostate cancer (PC) is one of the most urgent problems of modern urologic oncology in Russia because of a steady rise in morbidity and mortality rates associated with this disease. Radical prostatectomy (RP) and external beam radiotherapy (EBRT) or brachytherapy are mainstay treatments in patients with localized and locally advanced PC. Just the same, the rate of lymphogenic disease progression after radical treatment is as high as 15–40 %. At the same time, a search for a tumor focus leading to an increase in the marker is extremely important. If a local recurrence is detected after previous RP, there may be salvage EBRT. After verifying the relapse after salvage EBRT or brachytherapy, RP may be recommended to patients in the specialized centers having appropriate experience with this type of surgery. In patients with distant metastases, palliative hormonal therapy has been the only conventional method so far. Nonetheless, in a considerable number of patients, a marker recurrence may be associated with the so-called oligometastatic progression of the disease, in which the number of detected metastatic foci is minimal. The clinical introduction of promising and precise diagnostic methods having high sensitivity and specificity even with the minimal levels of prostate-specific antigen, such as magnetic resonance imaging and positron tomography, could substantially increase the number of detectable patients with oligometastases and propose new therapeutic conceptions for the treatment of this contingent of patients. Recently, in the literature there have been increasingly more works suggesting the possibility of using local treatments (surgery or radiotherapy) in patients with oligometastases when the disease progresses after radical treatment. The results of investigations show that a personalized approach and surgical or radiation treatments in selected patients make it possible to increase survival prior to the use of hormonal treatment and, in a number of cases, to completely abandon the latter. The paper gives a review of the literature data dealing with this problem.

Comparative study of an industrially used activated carbon of WSC-207C-GR brand, strongly basic anion exchanger MINIX, and weakly basic anion exchanger Purogold S992 in recovery of [Au(CN)2]– ions from cyanide aqueous solutions and slurries was carried out. It was found that the strongly basic anion exchanger MINIX has the highest adsorption rate of the cyanide complex of gold(I), whereas the activated carbon and the weakly basic ion exchanger possess a substantially higher selectivity toward the complex of gold(I). Use of each of the three sorbents makes it possible to solve the problem of the cyanide leaching of gold from ores containing natural substances that exhibit adsorbent properties with respect to the dicyanoaurate(I) ion. The influence exerted by the amount of kerosene additive and volume fraction of a sorbent on the efficiency of gold recovery by the sorbent in cyanidation of ores in the “carbon-in-pulp” and “resin-in-pulp” modes.

Possibility of using strongly basic anion exchange resin of MINIX brand and weakly basic anion exchange resin Purogold S992 brand in the high-temperature- caustic conditioning (HiTeCC) technological process for diminishing the loss of gold via adsorption on natural organic carbon-containing substances (pregrobbing phenomenon) in the course of cyanide leaching was studied. It was shown that the strongly basic anion exchanger MINIX has a higher affinity for the anion [Au(CN)2]−, compared with the microporous activated carbon WSC-207C-GR. As a result, the adsorbed dicyanoaurate(I) anion is transferred from the activated carbon to the ion-exchange resin. Reasons for binding of the dicyanoaurate(I) anion with active centers of activated carbons are considered, based on the fact that the adsorbent contains carbene-like carbon atoms. The existence of paramagnetic centers belonging to carbon atoms in the activated carbon was demonstrated by the EPR method. The suggested concept was used to diminish the loss of gold via partial oxidation of metallic gold in autoclave processing of pyrite- and arsenopyrite-containing concentrates.

The effect the porous structure of activated carbons obtained from furfural and coconut shells has on the kinetics of [Au(CN)2]− ion adsorption is studied. Effective diffusion coefficients for [Au(CN)2]− anions in transport and adsorbing pores and mass transfer coefficients in a transport system of the pores and in microporous zones are calculated using the statistical moments of the kinetic curve.

We have studied the processes occurring when alkaline aqueous solution of Na[Au(CN)2] is brought in contact with activated carbon surface. It has been shown that the adsorption of the gold cyanide complex occurs via several independent routes, one of them being accompanied with the partial breakdown of the inner sphere of the compound and free cyanide ions release into the solution. The latter process decreases the gold recovery by aqueous NaOH during the high-temperature (150°C) desorption. A prolonged storage of the adsorbent saturated with [Au(CN)2]− in air produces a similar result. The reasons of the observed phenomena have been discussed.

Sorbent capacity and kinetics of the adsorption process on synthetic carbons (FAS grade) and commercial coconut shell activated carbons were studied in the system activated carbon-aqueous solution of sodium dicyanoaurate(I). The effect of progressive activation of carbons on the adsorption value was analyzed. The method of moments was used to calculate the internal diffusion coefficients and show their relation to the structure of activated carbons.

Despite promising vista of the use of microRNA in molecular diagnosis of bladder cancer, there are few data on their expression profiles, which impedes assessment of diagnostic value of these marker molecules. In this study, suppression subtractive hybridization, on-chip hybridization, and high-throughput deep sequencing focused on profiling microRNA and assessing the diagnostic value of revealed marker molecules.

Our study using the nonlocal density functional theory (NDFT) showed that active coals might have a bidisperse microporous structure. The binomial equation of the theory of volume filling of micropores (TVFM) approximates well the nitrogen adsorption isotherms at relative pressures from 1 × 10−4 to 0.2. The dominant micropore sizes calculated in terms of the characteristic adsorption energy lie in the region of the maximum of the size distribution of micropores calculated by the NDFT method. The tentative micropore sizes can be determined from the modified second term of the TVFM equation. The Henry and BET equations describe very limited regions of the nitrogen adsorption isotherm on microporous active coals.

Goldcarb WSC-207C GR activated carbons with platinum and palladium complexes adsorbed from aqueous solutions of K2[Pt(CN)4], K2[Pt(CN)6], and K2[Pd(CN)4] were studied by the methods of X-ray photoelectron spectroscopy and IR spectroscopy with Fourier transformation, and also by MALDI massspectrometry. Platinum and palladium cyanide complexes are not reduced onto surface of active charcoal while adsorption. A certain part of the [Pd(CN)4]2− and [Pt(CN)4]2− anions directly bound to active centers on the activated carbon is oxidized more deeply and functions as particles-anchors, forming oligomers resembling Krogmann salt. A correspondence between the structure of the complex cyanometallate ion and a mode of its binding with active carbon is found. The adsorption of complex species with a linear structure or a square planar structure is defined by a possibility of the formation of donor-acceptor and metallophilic bonds. The mode of the anion [Au(CN)2]− binding with the surface of active carbon was considered.

Isotherms of nitrogen low-temperature adsorption on active FAS carbons and coconut-shell carbons were studied by the method of the density functional nonlocal theory. Distribution curves of micropore volumes in their width were obtained.m dodecyl sulfate in the presence of hydrogen peroxide under the action of UV light was studied.

An one-dimensional mathematical model addressing the field of tangential velocities, agitation power and other hydrodynamic features necessary for designing large-size unbaffled agitators with a precession impeller is proposed in this study. The adequacy of the model is confirmed by tests, published data, and lengthy positive operational results for industrial agitators with a volume of up to 1000 m3, designed for leaching of ore slurries.

The thermal behavior of crystalline Na[Au(CN)2] and the gold(I) cyanide complex adsorbed from neutral aqueous solution of Na[Au(CN)2] by the WSC-207C GR charcoal pre-washed from inorganic impurities was studied. The adsorption was established to lead to a significant decrease in the thermal stability of dicyanoaurate(I) anion. Using electron microscopy it was established that at the heating the adsorbent with the adsorbed [Au(CN)2]-anions up to 300°C labile metallic gold nanoparticles were formed. Chemisorption nature of adsorption of the [Au(CN)2]-anion by the activated carbon was assumed, and the nature of sorption sites involved in the formation of the primary bonds of gold(I) with the surface of the sorbent was considered.

Deceleration of gold electrowinning from model cyanide solutions on porous cathode of graphitized carbon felt was investigated. It was established that calcium ions present in the solution did not negatively affect the electrolysis rate. The main reason of the termination of gold electrowinning on the graphitized cathode was the corrosion of the stainless steel anode resulting in penetration into the cathode chamber of the electrolyzer of CrO 4 2− anions further reduced to Cr(III) and probably Cr(II) compounds. X-ray Photoelectron Spectroscopy investigation of the passivated carbon cathode showed that the film formed thereon consisted of Cr(III) compounds containing cyanide and hydroxy ligands. This film covers the active sites on the surface of the porous carbon cathode preventing the deposition thereon of ad-ions of gold(I). Inert aqua and hydroxo complexes of chromium(III) stronger impede the rate of gold(0) deposition on the porous carbon cathode than chromium(III) cyanide compounds. This fact originates presumably from the requirement of lower cathode potentials for the reduction of the former to labile chromium(II) complexes than those necessary for the thermodynamically stable anions [Cr(CN)6]3−.

Inorganic impurities (ash) in the composition of activated carbons of the H-type (AG-90, WSC-208C, and Norit RO 3515) and their effect on the adsorption of Na[Au(CN)2] from alkaline cyanide solutions were studied. Variants of presorption acid washing of carbons to raise their reactivity in the sorption process of Au(I) recovery from cyanide solutions and pulps and the order of technological procedures for diminishing the loss of Au(I) and adsorbent were considered. The effect of some solution components on the adsorption kinetics of the noble metal was characterized.

High-performance liquid chromatography and gas chromatography were used to reveal formation of hydroxyl radicals in air-saturated water containing activated carbon. Probable mechanisms of OH· formation are considered. The role of OH· radicals in the formation of carbene centers on the activated carbon surface is discussed. For interpreting the experimental data on atmospheric nitrogen fixation on activated carbon surface, probable mechanisms of nitrogen activation are explored by quantum-chemical methods. Highly reactive OH· radicals are unable to react with molecular nitrogen under mild conditions. A high reactivity of singlet and triplet carbenes of different nature on activated carbon surface with respect to N2 molecules was revealed by density functional theory methods.

Criteria used to choose activated carbons suitable for sorption recovery of the [Au(CN)2]- anion from cyanide ore pulps are considered. Results obtained in the development of authors’ own tests for determining the mechanical strength and loss of carbons via their disintegration in this technological process are presented. Changes occurring on the surface of grains of activated carbon in its agitation in abrasive media and specific features of the design of sorption apparatus that can be used for rationally carrying out carbon-in-pulp and carbon-in-leaching processes are discussed.

Published data on the effect of lead(II) compounds on the kinetics of dissolution of metallic gold and its extraction from ore materials and concentrates are considered.

The concentration constants of acid-base equilibria in aqueous solutions of cephotaxime and cephtriaxone were determined pH-metrically at 20°C against the background of 0.1, 0.4, 0.7, and 1.0 M solutions of KCl and KNO3. The thermodynamic constants of these equilibria were calculated by the extrapolation of the concentration constants to zero ionic strength according to the Huckel equation. Cephotaxime and cephtriaxone ionic form sizes were calculated by the semiempirical PM3 method for energetically favorable conformations.

The interaction of ampicillin with the Mn2+, Co2+, and Ni2+ ions in aqueous solution at 20°C (supporting electrolyte 0.1 M KNO3) was studied pH-metrically and spectrophotometrically. In weakly acidic and neutral media, Ni2+ forms with the anionic ampicillin species 1: 1 and 1: 2 complexes, whereas Mn2+ and Co2+ form only 1: 1 complexes. The stability constants of the complexes were determined, and their possible structures were discussed.

Specific features of designing of large-volume agitators for mechanical agitation of concentrated polydisperse suspensions are considered. Mathematical models and results of model experiments are applied to obtain calculational relations that can be use to determine technical parameters of industrial agitators. The designing procedure is confirmed by the experience of industrial use of agitators with a capacity of up to 1000 m3.

Sorption of [Au(CN)2]- ions from cyanide aqueous solutions with activated carbon fiber was studied, and the effect of the gas phase composition and additives (phenol, hydroquinone, ethanol, Na2SO3, Na2S2O3) on sorption was considered. The results are compared with data on interaction of C60 with [Au(CN)2]-.

Oxidation of cyanide anions with atmospheric oxygen in aqueous solutions in the presence of Na2SO3 and NaHSO3 mixture and CuSO4 as a catalyst was studied. The reaction mechanism was proposed.

Telomer repeats represented by hexamer (TTAGGG)n at chromosome termini are required for correct function and chromosome stability. At the same time, interstitial telomer sequence (ITS) located far from the chromosome ends are known for several mammalian genomes, including the human genome. It is assumed that these repeats mark the points of fusion or other chromosome reconstructions of ancestors. Exact localization of all interstitial telomer sequences in the genome could greatly improve our understanding of the mechanism of karyotype evolution and species origin. We have developed a software for a search of interstitial telomer sequences in complete sequences of mammalian genomes. We have demonstrated the evolutionary significance of repeats by an example of human chromosome 2. The results and supplementary materials are available at the site of the Institute of Cytology and Genetics: http://www.bionet.nsc.ru/labs/theorylabmain/orlov/telomere/.