66 research outputs found
Modeling the influence of age on the technical efficiency by sector and time periods
In today’s competitive economy, technological leadership and technical efficiency are key to the successful development of enterprises, countries and territories. This paper investigates the influence of factors on the technical efficiency of a business. Situations where technical efficiency is calculated by the DEA method, and its determinants are defined in regression models, including tobit regression models, have been considered. The determinants of technical efficiency identified by foreign researchers have been systematised. Modeling of the influence of the “Age” factor on the technical efficiency of enterprises in six leading sectors of Russia’s economy over the period 2015–2019 has been performed. It has been found that the “Age” factor has different effects on technical efficiency in different industry sectors. Particularly, in the food industry younger companies are more technically efficient, while mature companies are more technically efficient in the information technology sector. Accordingly, the directions and priorities for incentives should differ across sectors of the economy. In particular, the technological development of the food industry requires support for the generation processes of young enterprises and start-ups. In the information technology sector, the priority should be to support mature enterprises and the growth processes of young enterprises to maturity
Digital capital of Russian enterprises: development trends in the digitalisation of the economy and the coronavirus pandemic
The digitalisation of the economy and the global coronavirus pandemic transfer competition for consumers into a virtual Internet environment, in which the enterprise success depends on its digital capital, which includes an Internet communication system with potential consumers. The article reveals the regularities and trends in the development of the enterprises digital capital focused on the retail market for the period 2017–2021. Economic and variance analysis of digital capital indicators based on the enterprises formed samples has been carried out. It has been noted that the leaders in the demand for websites are the trade and services industries. The global coronavirus pandemic in 2020–2021 became a powerful growth driver, with the major effect on enterprise website promotion is observed with a one year lag (in 2021). It has been found that the most industries enterprises are practically not engaged in the paid traffic development for their sites. Only real estate agencies actively interact with advertising Internet services. It has been shown that the enterprises digital capital development constantly requires new impulses or growth drivers and enterprises in most studied industries do not use the full opportunities range for increasing digital capital
COMPREHENSIVE STUDY OF METAL OF PILOT FORGE INGOT MADE OF AUSTENITIC NITROGEN-CONTAINING Cr–Ni–Mn ALLOYING STEEL
В работе представлены результаты исследования кузнечного слитка массой 4,65 т из высокопрочной маломагнитной азотсодержащей стали марки 04Х20Н6Г11М2АФБ. Определено влияние плотности литого металла на структуру и свойства стали, количество и состав неметаллических включений, оценена степень ликвации элементов в металле слитка. Измерена магнитная проницаемость, и проведён анализ механических свойств.The paper presents the examination results of 4,65 t forging ingot made of high-strength non-magnetic nitrogen-bearing 04Kh20N6G11M2AFB (04Х20Н6Г11М2АФБ) steel. The influence of cast metal density on structure and properties of steel as well as the quantity and the composition of non-metallic inclusions were determined. A liquation degree of elements in an ingot metal was also evaluated. A magnetic permeability was measured and the analysis of mechanical properties was performed
STUDY OF MINIMAL RESIDUAL DISEASE BY MULTICOLOR FLOW CYTOMETRY IN MULTIPLE MYELOMA AFTER AUTOLOGOUS HEMATOPOIETIC STEM CELL TRANSPLANTATION
The frequency of achieving complete remission, as well as overall and disease-free survival, in multiple myeloma (MM) had increased due to introduction in MM treatment regimens of high-dose chemotherapy with following autologous hematopoietic stem cell transplantation (ASCT). However the number of relapses remains high, caused by persistence of residual tumor cells, i.e., the presence of minimal residual disease (MRD). One of the methods for MRD study is multicolor flow cytometry (MFC) where abnormal expression of surface antigens on myeloma plasma cells (PC) is determined. The aim of our study was to investigate the MRD by MFC before and after ASCT, the frequency of MRD-negative status achievement in complete remission (CR) patients at +100 days after ASCT and the frequency of abnormal expressed antigens on myeloma plasma cells. The study included40 MMpatients in CR at +100 days after ASCT and showed that the most common aberrations of PC were: abnormal absence of CD19 and/or CD27, decreased expression of CD38 and abnormal presence of CD56. The proportion of myeloma PCs from all bone marrow cells decreased significantly after ASCT: 20 % of patients acquired MRD-negative status, 10 % had a decrease in the number of abnormal PCs by one fold. Analysis of probability of immunochemical relapse showed that the worst prognosis was in patients with MRD-positive status before and after ASCT. During the MRD monitoring within 3-18 months, MRD-relapses were detected with the subsequent development of immunochemical relapse. The detection MRD in the dynamics is more informative than the study at only one step of therapy. It may help to select more adequate treatment for patient with multiple myeloma in each specific case
ВАРИАЦИИ СИЛЫ ТЯЖЕСТИ И СОВРЕМЕННАЯ ГЕОДИНАМИКА ЮГОЗАПАДНОЙ ЧАСТИ БАЙКАЛЬСКОГО РЕГИОНА
Modern methods for determination of gravity values make it possible to obtain measurements with the accuracy up to 10–9 from g0 of the normal value (up to 1 microgal = 10 m/sec2). While all the systematic and periodic effects are excluded, a question is raised about stability of the gravity field of the Earth over time. Changes of the altitude (the Earth’s radius) with time can be estimated with an accuracy of 0.1 mm by modern space geodetic techniques, such as VLBI method. Our experiments for evaluation of stability of the gravity values over the past decades are based on the data obtained by Russian and foreign observatories using absolute ballistic laser gravimeters. The results put a limit of 10–10 per year to changes of the Earth’s radius. These estimations can be useful for testing hypotheses in tectonics.Measurements of non-tidal variations of gravity (Δg), which were obtained from 1992 to 2012 at the Talaya seismic station (located in the south-western part of the Baikal region), are interpreted together with GPS observation data. At the Talaya seismic station, the linear component of gravity variations corresponds to changes in the elevation of this site. The correlation coefficient is close to the normal value of the vertical gradient of gravity. At this site, coseismic gravity variations at the time of the Kultuk earthquake (27 August 2008, Mw=6.3) were caused by a combined effect of the change of the site’s elevation and deformation of the crust. Our estimations of the coseismic effects are consistent with results obtained by modeling based on the available seismic data.Современные методы определения значения силы тяжести позволяют проводить измерения с точностью до 10–9 от g0 нормального значения (до 1 микрогала = 10 нм/с2). При этом исключаются все систематические и периодические эффекты и возникает вопрос о стабильности поля силы тяжести Земли во времени. Оценить изменения высоты (радиуса Земли) во времени с точностью до 0.1 мм позволяют современные методы космической геодезии (VLBI метод). Экспериментальные оценки стабильности значения силы тяжести за последние десятилетия сделаны по материалам отечественных и зарубежных обсерваторий, использующих абсолютные лазерные баллистические гравиметры. Полученные результаты ограничивают изменение радиуса Земли значением 10–10 в год. Эти оценки можно использовать для тестирования тектонических гипотез.Результаты измерений неприливных вариаций ускорения силы тяжести Δg, проведенных в 1992–2012 гг. на сейсмостанции «Талая» (юго-западная часть Байкальского региона), интерпретируются совместно с данными GPS-наблюдений. Линейная составляющая вариации силы тяжести на станции Талая соответствует изменениям высоты пункта. Коэффициент корреляции близок к нормальному значению вертикального градиента силы тяжести. Косейсмические вариации силы тяжести на этом пункте в эпоху Култукского землетрясения (27.08.2008 г., Мw=6.3) вызваны комплексным эффектом изменения высоты пункта и деформации земной коры. Оценки косейсмических эффектов соответствуют результатам моделирования на основе сейсмологических данных
Sequence-Specific Binding of Recombinant Zbed4 to DNA: Insights into Zbed4 Participation in Gene Transcription and Its Association with Other Proteins
Zbed4, a member of the BED subclass of Zinc-finger proteins, is expressed in cone photoreceptors and glial Müller cells of human retina whereas it is only present in Müller cells of mouse retina. To characterize structural and functional properties of Zbed4, enough amounts of purified protein were needed. Thus, recombinant Zbed4 was expressed in E. coli and its refolding conditions optimized for the production of homogenous and functionally active protein. Zbed4’s secondary structure, determined by circular dichroism spectroscopy, showed that this protein contains 32% α-helices, 18% β-sheets, 20% turns and 30% unordered structures. CASTing was used to identify the target sites of Zbed4 in DNA. The majority of the DNA fragments obtained contained poly-Gs and some of them had, in addition, the core signature of GC boxes; a few clones had only GC-boxes. With electrophoretic mobility shift assays we demonstrated that Zbed4 binds both not only to DNA and but also to RNA oligonucleotides with very high affinity, interacting with poly-G tracts that have a minimum of 5 Gs; its binding to and GC-box consensus sequences. However, the latter binding depends on the GC-box flanking nucleotides. We also found that Zbed4 interacts in Y79 retinoblastoma cells with nuclear and cytoplasmic proteins Scaffold Attachment Factor B1 (SAFB1), estrogen receptor alpha (ERα), and cellular myosin 9 (MYH9), as shown with immunoprecipitation and mass spectrometry studies as well as gel overlay assays. In addition, immunostaining corroborated the co-localization of Zbed4 with these proteins. Most importantly, in vitro experiments using constructs containing promoters of genes directing expression of the luciferase gene, showed that Zbed4 transactivates the transcription of those promoters with poly-G tracts
The acid-base characteristics of the surface of α-Al2O3: Potentiometry and wetting methods
THE EFFICACY OF POSACONAZOLE FOR PROPHYLAXIS OF INVASIVE MYCOSES IN PATIENTS WITH ACUTE MYELOID LEUKEMIA
Efficacy of posaconazole for prophylaxis was evaluated in 77 chemotherapy cycles in 59 patients with acute myeloid leukemia (AML) aged 39 (17–62) years from 2012 till 2017. Posaconazole was given in oral suspension 200 mg three times a day after meal during chemotherapy cycle or on 1st day after the cycle. Administration of posaconazole predominated in patients with de novo AML (84.5%) on 1st induction cycles (66.3%). Neutropenia was present in all patients with median duration of 22 days. Median duration of prophylaxis was 21 (2–57) days. Posaconazole prophylaxis was interrupted in 28 (36.4%) of 77 cases, mainly due to diarrhea (28.6%). In 17 (61%) of 28 cases prophylaxis was resumed within a median of 3 days. In 72 (93.5%) of cases duration of posaconazole prophylaxis was ≥ 7 days, in 5 (6.5%) cases < 7 days. Efficacy of prophylaxis was evaluated in cases of posaconazole duration ≥ 7 days. Invasive pulmonary aspergillosis (probable) was in 2 (2.7%) of 72 cases. Administration of posaconazole with duration ≥ 7 days was in 46 cases on chemotherapy cycle, in 26 cases – on first day after the cycle. Patients using Posaconazole after a course of chemotherapy in comparison with patients receiving the drug in the first days of the course had significantly less interruptions of prophylaxis (11,5% vs 41,3%, p=0.009) and a reduction in duration of Posaconazole using (19 days vs 27 days, p=0.007).One case of invasive aspergillosis was registered in each group.We confirmed the efficacy of posaconazole for prophylaxis of invasive mycoses in patients with AML. Administration of posaconazole prophylaxis on first day after the end of chemotherapy cycle results in saving of drug by reducing duration of posaconazole using by 8 days and does not increase the incidence of invasive mycoses
Infectious complications in patients with acute leukemia according to the duration of neutropenia
Introduction. Patients with hematological malignancies undergoing chemotherapy (CT) have high incidence of infections which profile is affected by various factors including neutropenia.Objective was to evaluate incidence and type of infections in patients with de novo acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) according to neutropenia duration.Materials and methods. Prospective study (2013–2015) included 110 patients (66 AML, 44 ALL) that received 480 CT cycles throughout 6 month.Results. Neutropenia with median duration of 15 (2–55) days was in 288 (60 %) of CT cycles. Infections occurred in 242 (50 %) of CT cycles and predominated in neutropenic compared to non-neutropenic patients (80 % vs 6 %, p <0.0001). Infections prevailed in patients with AML compared to ALL patients (93 % vs 18 %, p <0.0001) as in patients with neutropenia (96 % vs 45 %, p <0.0001) and without neutropenia (27 % vs 4 %, p = 0.02). Prolongation of neutropenia from 1–7 days to ≥22 days was associated with increase of infections rate from 52 to 96 % (p <0.0001). Incidence of infections in AML patients was high (92–100 %) regardless of neutropenia duration, whereas in ALL patients it increased from 25–33 to 91 % if neutropenia lengthened from 2 weeks to ≥22 days. During neutropenia the probability of fever of unknown origin was 33.9 %, clinically documented infection – 31.3 %, bacteremia – 17.2 %. They predominated in the first 2 weeks of neutropenia. Probability of invasive aspergillosis (IA) increased after 28 days of neutropenia and reached 66 % on the 55th day. First case of IA in patients with ALL was on 28th day of neutropenia whilst in AML patients – 4 (44 %) of 9 occurred more early (6–16 days of neutropenia). Nine (6 %) of 110 patients died, 4 (4 %) of them due to infection.Conclusions. Neutropenia was a predictor of infectious complications in patients with AML and ALL. Correlation between duration of neutropenia and incidence of infections was in patients with ALL, whereas in AML patients the rate of infections was high regardless of neutropenia duration. In patients with neutropenia for 2 weeks the most common types of infection were fever of unknown origin, clinically documented infection and bacteremia whilst IA predominated if neutropenia duration was ≥28 days
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