Distribution of the Number of Corners in Tree-like and Permutation Tableaux

In this abstract, we study tree-like tableaux and some of their probabilistic properties. Tree-like tableaux are in bijection with other combinatorial structures, including permutation tableaux, and have a connection to the partially asymmetric simple exclusion process (PASEP), an important model of interacting particles system. In particular, in the context of tree-like tableaux, a corner corresponds to a node occupied by a particle that could jump to the right while inner corners indicate a particle with an empty node to its left. Thus, the total number of corners represents the number of nodes at which PASEP can move, i.e., the total current activity of the system. As the number of inner corners and regular corners is connected, we limit our discussion to just regular corners and show that, asymptotically, the number of corners in a tableaux of length n is normally distributed. Furthermore, since the number of corners in tree-like tableaux are closely related to the number of corners in permutation tableaux, we will discuss the corners in the context of the latter tableaux

О РЕЗУЛЬТАТАХ АНКЕТИРОВАНИЯ ВРАЧЕЙ АКУШЕРОВ-ГИНЕКОЛОГОВ И ОЦЕНКИ УРОВНЯ ИХ ПОДГОТОВЛЕННОСТИ ПО ВОПРОСАМ КАЧЕСТВА МЕДИЦИНСКОЙ ПОМОЩИ

Introduction. One of the conditions for the provision of quality medical care is the involvement of all categories of medical personnel in the quality assurance process, which is impossible without clear knowledge of the theoretical aspects of this concept, including modern notions of conditions, structure, components, and criteria for assessing the quality. A sufficient level of awareness will allow the heads of medical organizations to build properly a quality assurance strategy with active involvement of employees, what is now recognized as one of the main principles of the quality management methodology. Unfortunately, until now the preparedness of medical workers on these issues is insufficient. Moreover, only single studies are devoted to the analysis of this problem, including among obstetrician-gynecological specialists. Research objective is to study the level of preparedness of maternity hospital doctors in the quality of medical care, their opinion on the level of quality and to develop a system of measurements to quality improvement. Material and methods. On the basis of one of the maternity hospitals of St. Petersburg, 95 doctors were questioned using a specially developed questionnaire. The questionnaire included self-assessment by doctors of their preparedness on quality issues, their assessment of the level of the quality in the basic organization, as well as questions to assess the real level of doctors’ knowledge. The correctness of the answers reflecting the current theoretical ideas about the structure, components, criteria for assessing the subjects of control was evaluated by experts of the Quality Service of the Organization. Data processing was carried out on a personal computer using the Statistica 6 software package. Based on the results of the study, recommendations were developed to optimize the training of personnel in the maternity hospital on the quality of medical care and to improve the quality management in the Organization. Results. Assessment of the level of knowledge of medical personnel of the maternity hospital on the quality of medical care showed that 51 respondents (53.7 %) considered themselves sufficiently prepared; 24 (25.2 %) found themselves not quite prepared; 19 (20.0 %) could not assess the level of knowledge on this issue; 1 (1.1 %) refrained from responding. None of the interviewed employees indicated a lack of such knowledge. Answering the special questions (quality criteria, statistical indicators of the maternity hospital, subjects of quality control), some of the respondents could not give the correct answer. The main source of information about the quality of medical care are conferences (62.1 % of respondents noted), thematic cycles of professional development (53.4 %), self-training (41.8 %). The average mark of the assessment of the quality in the basic hospital was 4.2±0.87 (on 5-point grading system). The main suggestions of respondents on quality improvement were: reduction of workload and increase in the number of personnel, improvement of the system of material incentives for employees, material support of the institution. Conclusions. According to the results of the study, the measurements aimed at improving the level of doctor’s knowledge in such subject as medical care quality and stimulating employees to constant work to improve the quality are presented.Одним из условий оказания качественной медицинской помощи (КМП) является  вовлеченность в процесс обеспечения качества всех категорий медицинского персонала, которая невозможна без наличия у них четких знаний о теоретических аспектах данного понятия, включая современные представления об условиях, структуре, компонентах, критериях оценки качества. Достаточный уровень осведомленности позволит руководителям медицинских организаций правильно выстраивать стратегию обеспечения качества с активным вовлечением сотрудников, что в настоящее время признано одним из основных принципов методологии менеджмента качества. К сожалению, до настоящего времени подготовленность медицинских работников по данным вопросам недостаточна. Более того, лишь единичные исследования посвящены анализу этой проблемы, в т.ч. среди работающих в медицинских организациях акушерско-гинекологического профиля

Photoreceptor rescue and toxicity induced by different calpain inhibitors.

Photoreceptor degeneration is the hallmark of a group of inherited blinding diseases collectively termed retinitis pigmentosa (RP); a major cause of blindness in humans. RP is at present untreatable and the underlying neurodegenerative mechanisms are largely unknown, even though the genetic causes are often established. The activation of calpain-type proteases may play an important role in cell death in various neuronal tissues, including the retina. We therefore tested the efficacy of two different calpain inhibitors in preventing cell death in the retinal degeneration (rd1) human homologous mouse model for RP. Pharmacological inhibition of calpain activity in rd1 organotypic retinal explants had ambiguous effects on photoreceptor viability. Calpain inhibitor XI had protective effects when applied for short periods of time (16 h) but demonstrated substantial levels of toxicity in both wild-type and rd1 retina when used over several days. In contrast, the highly specific calpain inhibitor calpastatin peptide reduced photoreceptor cell death in vitro after both short and prolonged exposure, an effect that was also evident after in vivo application via intravitreal injection. These findings highlight the importance of calpain activation for photoreceptor cell death but also for photoreceptor survival and propose the use of highly specific calpain inhibitors to prevent or delay RP

THE RESULTS OF THE SURVEY OF OBSTETRICIAN-GYNECOLOGISTS AND ASSESSMENT OF THEIR LEVEL OF PREPAREDNESS ON THE ISSUES OF QUALITY OF MEDICAL CARE

Introduction. One of the conditions for the provision of quality medical care is the involvement of all categories of medical personnel in the quality assurance process, which is impossible without clear knowledge of the theoretical aspects of this concept, including modern notions of conditions, structure, components, and criteria for assessing the quality. A sufficient level of awareness will allow the heads of medical organizations to build properly a quality assurance strategy with active involvement of employees, what is now recognized as one of the main principles of the quality management methodology. Unfortunately, until now the preparedness of medical workers on these issues is insufficient. Moreover, only single studies are devoted to the analysis of this problem, including among obstetrician-gynecological specialists. Research objective is to study the level of preparedness of maternity hospital doctors in the quality of medical care, their opinion on the level of quality and to develop a system of measurements to quality improvement. Material and methods. On the basis of one of the maternity hospitals of St. Petersburg, 95 doctors were questioned using a specially developed questionnaire. The questionnaire included self-assessment by doctors of their preparedness on quality issues, their assessment of the level of the quality in the basic organization, as well as questions to assess the real level of doctors’ knowledge. The correctness of the answers reflecting the current theoretical ideas about the structure, components, criteria for assessing the subjects of control was evaluated by experts of the Quality Service of the Organization. Data processing was carried out on a personal computer using the Statistica 6 software package. Based on the results of the study, recommendations were developed to optimize the training of personnel in the maternity hospital on the quality of medical care and to improve the quality management in the Organization. Results. Assessment of the level of knowledge of medical personnel of the maternity hospital on the quality of medical care showed that 51 respondents (53.7 %) considered themselves sufficiently prepared; 24 (25.2 %) found themselves not quite prepared; 19 (20.0 %) could not assess the level of knowledge on this issue; 1 (1.1 %) refrained from responding. None of the interviewed employees indicated a lack of such knowledge. Answering the special questions (quality criteria, statistical indicators of the maternity hospital, subjects of quality control), some of the respondents could not give the correct answer. The main source of information about the quality of medical care are conferences (62.1 % of respondents noted), thematic cycles of professional development (53.4 %), self-training (41.8 %). The average mark of the assessment of the quality in the basic hospital was 4.2±0.87 (on 5-point grading system). The main suggestions of respondents on quality improvement were: reduction of workload and increase in the number of personnel, improvement of the system of material incentives for employees, material support of the institution. Conclusions. According to the results of the study, the measurements aimed at improving the level of doctor’s knowledge in such subject as medical care quality and stimulating employees to constant work to improve the quality are presented

Method for control the mechanical parameters of overhead power lines based on improved inclinometry

Structural elements of overhead power transmission lines are experiencing both horizontal and vertical loads. Wires and cables are elements of the overhead power line, on which changes in mechanical loads are observed to a greater degree. This occurs due to the change in the tension force of the wire/cable depending on the temperature and the formation of icy-rime deposits on it, as well as fluctuations in wind gusts. The article describes the most common systems and methods for determining the mechanical loads on an overhead power transmission line. A method is proposed for calculating the mechanical loads on an overhead transmission line based on mathematical models of a flexible wire, rope and a model for determining ice deposits on wires, taking into account the rotation of the wire/cable around its axis. A comparison of the improved inclinometry method with the method developed earlier for the case of formation of ice deposits on the S-50 cable has been carried out. A comparison was made on the error in determining the tension of the S-50 ground-wire protection cable using the method developed to control the mechanical parameters of overhead power lines, which takes into account the wire/cable rotation around its axis and the method for determining icy-rime deposits developed earlier. The developed method allows determining the elongation of the wire/cable in the span with one anchor support, as well as the strength of its tension with greater accuracy. However, additional clarification is required due to the influence of the wind, the formation of icy-rime deposits of various shapes, as well as the structural limitations of the wire/cable rotation when attaching it to the support

Autocrine and paracrine nitric oxide regulate attachment of human osteoclasts.

Nitric oxide (NO) can reduce bone loss in chronic bone diseases. NO inhibits or kills osteoclasts, but the mechanism of action of NO in human bone turnover is not clear. To address this, we studied effects of NO on attachment and motility of human osteoclasts on mineralized and tissue culture substrates under defined conditions. Osteoclasts were differentiated in vitro from CD14 selected monocytes in RANKL and CSF-1, and characterized by cathepsin K expression, tartrate-resistant acid phosphatase (TRAP) activity, acid secretion, and lacunar resorption. Cell attachment was labeled with monoclonal antibody 23C6, specific for a binding domain of a key osteoclast attachment protein, the CD51/CD61 integrin dimer (alpha(v)beta(3)), with or without cell permeabilization. A ring of integrin attachment during bone degradation delimits an extracellular acid compartment, while alpha(v)beta(3) forms focal attachments on non-resorbable substrates. On resorbable substrate but not non-resorbable substrate, alpha(v)beta(3) labeling required cell permeabilization, in keeping with the membrane-matrix apposition that excludes large molecules and allows extracellular acidification. Acid secretion was labeled with the fluorescent weak base indicator lysotracker. NO donors, S-nitroso-N-acetyl penicillamine (SNAP) or sodium nitroprusside (SNP), downmodulated acid secretion simultaneously with cytoskeletal rearrangement, with alpha(v)beta(3) redistributed to a discontinuous pattern that labeled, on bone substrate, without membrane permeabilization. These effects were reversible, and an inhibitor of NO synthesis, N(G)-monomethyl-L-arginine (l-NMMA), increased acid secretion and decreased heterogeneity of attachment structures, showing that NO is an autocrine regulator of attachment. A hydrolysis-resistant activating cGMP analog 8-(4-chlorophenylthio)guanosine-3',5'-cyclic monophosphate replicated effects of NO donors, while an inhibiting analog, 8-(4-chlorophenylthio)guanosine-3',5'-cyclic monophosphorothioate, Rp-isomer, opposed them. On tissue culture or mineralized substrates, NO or cGMP analogs directly regulated motility; after washout cells reattached and survived for days. We conclude that NO is produced by human osteoclasts and regulates acid secretion and cellular motility, in keeping with autocrine and paracrine NO regulation of the resorption cycle

Model of own harmonic conductor oscillations for tasks of monitoring the status of airline power transmission lines

The article substantiates the relevance of the inspection of overhead power lines by determining the mechanical loads of the conductors. The conductor sways under the action of external loads and variable internal mechanical loads. The conductor behaves in span like a pendulum. Using the inclinometric method, it is possible to determine the deviations of the conductor in space from its equilibrium position. Having restored the geometry of the conductor in the span of an overhead power line, mechanical loads can be determined. A model of the harmonic oscillations of the conductor in flight is derived to assess the mechanical loads of the conductor overhead power lines. This mathematical model is based on mathematical models of a flexible thread and a model of a physical pendulum. A conductor is a physical pendulum, where the conductor acts as the body, and in the role of the fixed axis of rotation, a straight line passing through the suspension points of the conductor. The developed model allows you to determine the arrow of its sag from the period of oscillations of the conductor in the span. The article considers algorithms for calculating the conductor sag arrows for two cases: the conductor suspension points are at the same height; conductor suspension points are at different heights. A theoretical calculation is given for a model of a span overhead power line with an estimate of the sensitivity of the developed model and its error in determining the sag of the conductor. Using the arrow of the conductor sag, you can restore its geometry, and hence the mechanical load of the conductor. Therefore, knowing the initial geometric parameters of the span of the overhead power line and the current period of the conductor’s oscillations, it is possible to examine its current state