System-object modeling of quality management system of medical

The article discusses the problems that commercial organizations face when undergoing external audits of the quality management system. The analysis of the domestic practice of certification of quality management systems is presented. The authors propose the use of system-object simulation to improve the efficiency of the quality management system, as well as to simplify the first certification procedur

Influence of the Mo₁₀Ni₃C₃B phase on the hardness and fracture toughness of Mo-Ni-C-B cermet: experimental and theoretical study

We obtained the decreasing of hardness and comparable values of the fracture toughness of Mo₂NiB₂‑Ni cermets due to the formation of Mo₁₀Ni₃C3B phase. To understand the effect of the Mo₁₀Ni₃C₃B phase on the mechanical properties of the cermet, first-principles calculations were applied to investigate the elastic, electronic, and thermodynamic properties of this phas

Intraoperative Intraluminal Endoscopy in the Surgical Treatment of Patients with Esophageal Diverticula of Various Localization

Aim. To improve the results of surgical treatment of patients with esophageal diverticulum of various localization using intraoperative intraluminal endoscopy. Materials and Methods: The Department of Surgery of the Esophagus and Stomach, the Petrovsky National Research Centre of Surgery, has accumulated a large experience in treating diverticulosis patients. Thus, during the 2010–2018 period, 74 patients with esophageal diverticula of various localization were operated. Out of them, 56 (75.7 %), 10 (13.5 %) and 8 (10.8 %) patients underwent surgical treatment with respect to faringo-esophageal, bifurcation and epiphrenic diverticula, respectively. The patients were divided into two groups: 31 people (41.9 %) in the main group underwent diverticulectomy with intraoperative intraluminal endoscopic assistance (IVEA), while 43 (58.1 %) people in the control group underwent diverticulectomy without IVEA. Intraoperatively, at the stage of discovering diverticulum, the endoscopist applied transillumination and air insufflation in the cavity of the diverticulum, followed by controlling the mobilization of diverticulum. At the resection stage, the completeness of the surgical removal was controlled, along with the absence of esophageal lumen narrowing after sewing the neck of the diverticulum using a linear stapler.Results. The average duration of the operation in patients with Zenker’s diverticula and those in the control group was 45.5 ± 8.8 min and 73.8 ± 12.7 min (p < 0.05), respectively. In patients with the diverticula of the middle and lower third of the esophagus, the average surgery duration was equal to 120.3 ± 11.2 min and 150.5 ± 17.3 (p <0.05) min in the main and control groups, respectively. Radiological examination 2–3 days after surgery revealed no complications in the main group. In the control group, 2 (4.7 %) patients showed a small leakage of the contrast agent outside the esophagus (stopped conservatively). Signs of mild dysphagia when taking solid foods were detected in 1 (2.4 %) patient of the control group. This condition was associated with excessive ingress of the esophageal wall into the apparatus suture, which led to a slight narrowing of its lumen. No patients with dysphagia in the postoperative period were recorded in the main group. Conclusion: The combination of surgical treatment of esophageal diverticula with IVEA allows the duration of surgery to be optimized, deformation of the esophageal lumen to be avoided, possible complications to be minimized, thereby improving the results of surgical treatment

Dissecting the long-term emission behaviour of the BL Lac object Mrk 421

We report on long-term multiwavelengthmonitoring of blazar Mrk 421 by the GLAST-AGILE Support Program of the Whole Earth Blazar Telescope (GASP-WEBT) collaboration and Steward Observatory, and by the Swift and Fermi satellites. We study the source behaviour in the period 2007–2015, characterized by several extreme flares. The ratio between the optical, X-ray and γ -ray fluxes is very variable. The γ -ray flux variations show a fair correlation with the optical ones starting from 2012.We analyse spectropolarimetric data and find wavelengthdependence of the polarization degree (P), which is compatible with the presence of the host galaxy, and no wavelength dependence of the electric vector polarization angle (EVPA). Optical polarimetry shows a lack of simple correlation between P and flux and wide rotations of the EVPA.We build broad-band spectral energy distributions with simultaneous near-infrared and optical data from the GASP-WEBT and ultraviolet and X-ray data from the Swift satellite. They show strong variability in both flux and X-ray spectral shape and suggest a shift of the synchrotron peak up to a factor of ∼50 in frequency. The interpretation of the flux and spectral variability is compatible with jet models including at least two emitting regions that can change their orientation with respect to the line of sight.http://10.0.4.69/mnras/stx2185Accepted manuscrip

Formation of regulatory modules by local sequence duplication

Turnover of regulatory sequence and function is an important part of molecular evolution. But what are the modes of sequence evolution leading to rapid formation and loss of regulatory sites? Here, we show that a large fraction of neighboring transcription factor binding sites in the fly genome have formed from a common sequence origin by local duplications. This mode of evolution is found to produce regulatory information: duplications can seed new sites in the neighborhood of existing sites. Duplicate seeds evolve subsequently by point mutations, often towards binding a different factor than their ancestral neighbor sites. These results are based on a statistical analysis of 346 cis-regulatory modules in the Drosophila melanogaster genome, and a comparison set of intergenic regulatory sequence in Saccharomyces cerevisiae. In fly regulatory modules, pairs of binding sites show significantly enhanced sequence similarity up to distances of about 50 bp. We analyze these data in terms of an evolutionary model with two distinct modes of site formation: (i) evolution from independent sequence origin and (ii) divergent evolution following duplication of a common ancestor sequence. Our results suggest that pervasive formation of binding sites by local sequence duplications distinguishes the complex regulatory architecture of higher eukaryotes from the simpler architecture of unicellular organisms

Метаболизм головного мозга у пациентов с COVID-19 по данным мультивоксельной 1H-МРС: проспективное исследование

INTRODUCTION: Members of the coronavirus family can affect the human central nervous system, causing various neurological complications in patients with SARS-CoV-2. Proton magnetic resonance spectroscopy (1H-MRS) seems to be a promising technique for assessing the prognosis of persistent neurological manifestations and complications, determining the completeness of a patient’s recovery during long-term follow-up. OBJECTIVE: To study changes in the metabolites profile in the brain with relation to cognitive impairment in patients with COVID-19.MATERIALS AND METHODS: 68 patients with verified COVID-19 and neurological complaints underwent a diagnostic workup, including a psychoneurological assessment and MRI of the brain with multivoxel proton magnetic resonance spectroscopy (1H-MRS), starting in the first 2 weeks from the onset of the disease. In 11 patients, a complex examination was repeated 7–8 months after the onset of the disease. The exclusion criteria were acute severe neurological symptoms, age over 65 years, artificial lung ventilation, lung CT score III–IV, as well as information about pre-Covid neuropsychiatric disorders. As a control group, earlier collected data of 10 healthy volunteers (age 30–67 years) were taken from a local database. Statistics: Intergroup differences in the ratios of metabolites peak areas determined by the 1H-MPC method were assessed using the nonparametric Mann-Whitney test with Bonferroni’s correction for multiple comparisons. Values were considered statistically significant at p<0.05. RESULTS: According to 1H-MRS, all patients with COVID-19 showed metabolic changes in the brain: a statistically significant increase in mI/Cr in the white and gray matter and a diffuse decrease in the levels of Cho/Cr in the supraventricular white matter, even in the absence of any changes in structural MRI. DISCUSSOIN: Patients were divided into three subgroups according to the severity of neurological symptoms that arose with the onset of the coronavirus infection. The most pronounced metabolic changes were found in the group with severe neurological manifestations (NM). At follow-up, a gradual recovery of the metabolite profile was noted, but in our sample group complete normalization was not achieved within the specified time frame. CONCLUSION: The obtained data indicate metabolic changes associated with SARS-CoV-2 infection, as well as the prospects for using the 1H-MPC technique in the diagnosis of neurological complications of the new coronavirus infection, including manifestations of a psychoneurological syndrome associated with COVID-19.><0.05.RESULTS: According to 1H-MRS, all patients with COVID-19 showed metabolic changes in the brain: a statistically significant increase in mI/Cr in the white and gray matter and a diffuse decrease in the levels of Cho/Cr in the supraventricular white matter, even in the absence of any changes in structural MRI.DISCUSSOIN: Patients were divided into three subgroups according to the severity of neurological symptoms that arose with the onset of the coronavirus infection. The most pronounced metabolic changes were found in the group with severe neurological manifestations (NM). At follow-up, a gradual recovery of the metabolite profile was noted, but in our sample group complete normalization was not achieved within the specified time frame.CONCLUSION: The obtained data indicate metabolic changes associated with SARS-CoV-2 infection, as well as the prospects for using the 1H-MPC technique in the diagnosis of neurological complications of the new coronavirus infection, including manifestations of a psychoneurological syndrome associated with COVID-19.ВВЕДЕНИЕ: Представители семейства коронавирусов могут воздействовать на центральную нервную систему человека, вызывая различные неврологические осложнения у пациентов с SARS-CoV-2. Перспективной методикой для оценки прогноза стойких неврологических проявлений и осложнений, определения при долгосрочном наблюдении полноты реабилитации пациента представляется протонная магнитно-резонансная спектроскопия (1H-МРС).ЦЕЛЬ: Изучить изменения профиля метаболитов в веществе головного мозга в сопоставлении с когнитивными нарушениями у больных при COVID-19.МАТЕРИАЛЫ И  МЕТОДЫ: 68 пациентам с  верифицированным диагнозом COVID-19 и  неврологическими жалобами выполнен диагностический комплекс, включающий психоневрологическую оценку и  МРТ головного мозга, в  том числе многовоксельную 1H-МРС, начиная с первых 2 недель от начала заболевания. 11 пациентам комплексное обследование было выполнено в динамике, спустя 7–8 месяцев от начала заболевания. Критериями исключения была острая грубая неврологическая симптоматика, возраст старше 65 лет, нахождение на ИВЛ, КТ легких III–IV, а также информация о психоневрологических нарушениях в пре-ковидный период. В качестве группы контроля были взяты данные 10 здоровых добровольцев (возраст 30–67 лет) из локальной базы данных, собранной ранее. Статистика: Межгрупповые различия отношений площадей пиков метаболитов, определяемых методом 1H-МРС, оценивались при помощи непараметрического критерия Манна–Уитни с поправкой Бонферрони на множественность сравнений. Значения считались статистически значимыми при р<0,05. РЕЗУЛЬТАТЫ: По данным 1H-МРС у всех пациентов с COVID-19 были выявлены метаболические изменения головного мозга: статистически значимое нарастание показателей mI/Cr в белом и сером веществе и диффузное снижение уровней Cho/Cr в суправентрикулярном белом веществе даже при отсутствии каких-либо изменений на структурной МРТ. ОБСУЖДЕНИЕ: Пациенты были разделены на три подгруппы по степени выраженности неврологических симптомов, возникших с началом коронавирусной инфекции. Наиболее выраженные метаболические изменения были выявлены в группе с тяжелыми неврологическими проявлениями (НП). При динамическом контроле отмечается постепенное восстановление профиля метаболитов, но в нашей выборке в указанные сроки полная нормализация не была достигнута. ЗАКЛЮЧЕНИЕ: Полученные данные свидетельствуют о метаболических изменениях при инфицировании SARS-CoV-2, а также перспективности применения методики 1H-МРС в диагностике неврологических осложнений новой коронавирусной инфекции, включая проявления психоневрологического синдрома, ассоциированного с COVID-19. ><0,05.РЕЗУЛЬТАТЫ: По данным 1H-МРС у всех пациентов с COVID-19 были выявлены метаболические изменения головного мозга: статистически значимое нарастание показателей mI/Cr в белом и сером веществе и диффузное снижение уровней Cho/Cr в суправентрикулярном белом веществе даже при отсутствии каких-либо изменений на структурной МРТ.ОБСУЖДЕНИЕ: Пациенты были разделены на три подгруппы по степени выраженности неврологических симптомов, возникших с началом коронавирусной инфекции. Наиболее выраженные метаболические изменения были выявлены в группе с тяжелыми неврологическими проявлениями (НП). При динамическом контроле отмечается постепенное восстановление профиля метаболитов, но в нашей выборке в указанные сроки полная нормализация не была достигнута.ЗАКЛЮЧЕНИЕ: Полученные данные свидетельствуют о метаболических изменениях при инфицировании SARS-CoV-2, а также перспективности применения методики 1H-МРС в диагностике неврологических осложнений новой коронавирусной инфекции, включая проявления психоневрологического синдрома, ассоциированного с COVID-19

Dissecting the long-term emission behaviour of the BL Lac object Mrk 421

© 2017 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. We report on long-term multiwavelength monitoring of blazar Mrk 421 by the GLAST-AGILE Support Program of the Whole Earth Blazar Telescope (GASP-WEBT) collaboration and Steward Observatory, and by the Swift and Fermi satellites. We study the source behaviour in the period 2007-2015, characterized by several extreme flares. The ratio between the optical, X-ray and γ-ray fluxes is very variable. The γ-ray flux variations show a fair correlation with the optical ones starting from 2012. We analyse spectropolarimetric data and find wavelength-dependence of the polarization degree (P), which is compatible with the presence of the host galaxy, and no wavelength dependence of the electric vector polarization angle (EVPA). Optical polarimetry shows a lack of simple correlation between P and flux and wide rotations of the EVPA. We build broad-band spectral energy distributions with simultaneous near-infrared and optical data from the GASP-WEBT and ultraviolet and X-ray data from the Swift satellite. They show strong variability in both flux and X-ray spectr al shape and suggest a shift of the synchrotron peak up to a factor of ~50 in frequency. The interpretation of the flux and spectral variability is compatible with jet models including at least two emitting regions that can change their orientation with respect to the line of sight

Dissecting the long-term emission behaviour of the BL Lac object Mrk 421

We report on long-term multiwavelength monitoring of blazar Mrk 421 by the GLAST-AGILE Support Program of the Whole Earth Blazar Telescope (GASP-WEBT) collaboration and Steward Observatory, and by the Swift and Fermi satellites. We study the source behaviour in the period 2007-2015, characterized by several extreme flares. The ratio between the optical, X-ray and gamma-ray fluxes is very variable. The gamma-ray flux variations show a fair correlation with the optical ones starting from 2012. We analyse spectropolarimetric data and find wavelength-dependence of the polarization degree (P), which is compatible with the presence of the host galaxy, and no wavelength dependence of the electric vector polarization angle (EVPA). Optical polarimetry shows a lack of simple correlation between P and flux and wide rotations of the EVPA. We build broad-band spectral energy distributions with simultaneous near-infrared and optical data from the GASP-WEBT and ultraviolet and X-ray data from the Swift satellite. They show strong variability in both flux and X-ray spectral shape and suggest a shift of the synchrotron peak up to a factor of similar to 50 in frequency. The interpretation of the flux and spectral variability is compatible with jet models including at least two emitting regions that can change their orientation with respect to the line of sight

THE CASE OF SUCCESSFUL APPLICATION OF EMBOLIZING SYSTEM IN DISTAL PERFORATION OF CORONARY ARTERY

THE CASE OF SUCCESSFUL APPLICATION OF EMBOLIZING SYSTEM IN DISTAL PERFORATION OF CORONARY ARTERY