Дослідження енергоефективності процесів механічного руйнування зношених автомобільних шин

We studied the process of cutting the worn pneumatic Bridgestone tire the size of 7.1/11.0-5 using the cutting tool made of alloys of grades R6M5 and T15K6, resulting in the obtained data array on the reduced cutting forces. Regression coefficients were calculated, which formed the basis of a mathematical model in the form of a second-order polynomial. The constructed mathematical model expresses cutting forces dependence on the totality of geometrical parameters and hardness of the cutting tool’s material and operational parameters of the cutting process. Using it can help determine the combination of optimal geometrical parameters, material of the cutting tool and operational parameters in order to ensure the minimization of cutting forces and energy consumption for the cutting process as a whole.The mathematical model was refined based on the obtained equation of cutting force dependences on tensile strength of the materials of automobile tires. The adequacy of the refined model was confirmed by estimating homogeneity of variances of the estimated and experimental values of cutting forces by using a statistical Fischer criterion. We determined effective operational parameters: spindle rotation frequency and cutting tool feed; geometrical parameters and hardness of the cutting tool’s material, which ensure minimal power consumption when cutting worn automobile tiresПроведены исследования процесса обработки резанием изношенных пневматических шин режущим инструментом из сплавов марок Р6М5 і Т15К6. Полученная математическая модель формирования сил резания при резки пневматических шин пополам. Определены эффективные режимные параметры: частота вращения шпинделя станка и подача режущего инструмента, геометрические параметры и твердость материала режущего инструмента, которые обеспечивают минимальные энергозатратыПроведені дослідження процесу обробки різанням зношених пневматичних шин ріжучим інструментом зі сплавів марок Р6М5 і Т15К6. Отримана математична модель формування сил різання при розрізання пневматичних шин навпіл. Визначено ефективні режимні параметри: частота обертання шпинделя верстата і подача ріжучого інструменту, геометричні параметри і твердість матеріалу ріжучого інструменту, які забезпечують мінімальні енерговитрат

The First Genome from the Basal Monocot Family Has Been Misnamed: Taxonomic Identity of Acorus tatarinowii (Acoraceae), a Source of Numerous Chemical Compounds of Pharmaceutical Importance

The basalmost monocot genus Acorus is well-known for its use in traditional oriental medicine. It comprises the groups of A. calamus and A. gramineus. A recent study recognized three species in the latter group, A. gramineus, A. macrospadiceus, and A. tatarinowii. The material currently known as A. tatarinowii has been extensively studied as a source of various chemical compounds and for producing the first published genome of Acorus, which is important for understanding the origin and evolution of monocots. Using the data from morphology, anatomy, and biogeography, we argue that the type material of A. tatarinowii does not match the interpretation of the species name as adopted in the current literature and herbarium collections (to a taxon of the A. gramineus group from Southeast Asia) but rather belongs to the A. calamus group. Moreover, the name A. macrospadiceus also cannot be used because it was invalidly published. Under a narrow species concept, other appropriate species names should be found or proposed for the plants currently named A. tatarinowii and A. macrospadiceus. However, we discourage the use of a narrow species concept in the A. gramineus group as insufficiently justified and suggest recognizing a single polymorphic species, A. gramineus s.l., at least until a comprehensive taxonomic revision of the group is available. Apart from the presentation of our revised taxonomic framework, we update the geographical distributions of Acorus species in Vietnam, Laos, and Thailand

Створення модернізованих фільтрувальних паперових матеріалів для очистки води та оцінка їх властивостей

Filtering paper materials (FPM), which are easy to recycle, are widely applied to water purification. The main disadvantage of the absolute majority of filtering materials, including paper, is their tendency to biofouling. This drawback considerably limits or even sometimes makes it impossible to use filtering materials and/or sorbents in a certain medium. In connection with the above, the object of our study was the process of water purification using the FPM with disinfecting properties based on modified cellulose fibers and natural sorbent palygorskite, which can adsorb mechanical impurities, heavy metal ions, entero-viruses, and bacteria.It was found that the samples of modified filtering paper materials with the highest density and lowest thickness and the samples with the lowest density and the highest thickness have higher filtration and sorption capacity compared to samples with the mean values of these technological characteristics.Swelling of cellulose fibers reduces the impact of the compositional structure of the studied FPM samples on their filtering capability and increases the impact of the compositional structure on the sorption ability of these FPM.It was established that the samples with the introduction of about 40 % phosphoric ester of cellulose into their composition have the best technological characteristics.The character of dependence of the rate of filtration process on consumption of purified water, thickness, density and composition of FPM was established. The obtained mathematical models are presented by second-order polynomial and make it possible to take into consideration not only technical specifications, but also the impact of the FPM composition on the rate of filtration process of purified water. Among the studied parameters, the content of sulfate viscose or sulfate bleached viscose in paper-forming mass of the studied samples and consumption of the purified water have the highest impact on the rate of the filtration process at constant pressure and contamination concentration. The proposed mathematical models also allow to determine the necessary compositional structure for obtaining FPM with determined propertiesДля очистки воды широкое применение нашли материалы бумажные фильтровальные (МБФ), которые легко поддаются утилизации. Основным недостатком абсолютного большинства фильтровальных материалов, в том числе и бумажных, является их склонность к биообрастанию. Данный недостаток существенно ограничивает или иногда даже делает невозможным использование фильтровальных материалов и / или сорбентов в определенной сфере. В связи с вышеизложенным, объектом нашего исследования стал процесс очистки воды с использованием МБФ с обеззараживающими свойствами на основе модифицированных целлюлозных волокон и природного сорбента палыгорскит, которые могут сорбировать механические примеси, ионы тяжелых металлов, энтеровирусы и бактерии.Установлено, что образцы модифицированных материалов бумажных фильтровальных с наибольшей плотностью и наименьшей толщиной и образцы с наименьшей плотностью и наибольшей толщиной имеют большую фильтрационную и сорбционной способности по сравнению с образцами со средними значениями этих технологических характеристик.Набухание целлюлозных волокон уменьшает силу воздействия композиционного состава исследованных образцов МБФ на их фильтровальную способность и увеличивает силу воздействия композиционного состава на сорбционную способность этих МБФ.Установлено, что лучшие технологические характеристики имеют образцы в состав которых было введено около 40 % фосфорного эфира целлюлозы.Установлен характер зависимости скорости процесса фильтрации от расхода очищаемой воды, толщины, плотности и композиционного состава МПФ. Полученные математические модели представлены полиномом второго порядка и позволяют учитывать не только технические характеристики, но и влияние композиционного состава МПФ на скорость процесса фильтрации очищаемой воды. Из исследованных параметров наибольшие силы влияния на скорость процесса фильтрации при постоянных давлении и концентрации загрязнения имеют содержание сульфитной вискозной или сульфатной беленой целлюлозы в бумагообразующей массе исследованных образцов и расходы очищаемой воды. Предложенные математические модели позволяют также определить необходимый композиционный состав для получения МПФ с заданными свойствамиДля очистки води широкого застосування знайшли матеріали паперові фільтрувальні (МПФ), які легко піддаються утилізації. Основним недоліком абсолютної більшості фільтрувальних матеріалів, в тому числі і паперових, є їх схильність до біообростання. Даний недолік суттєво обмежує чи інколи навіть унеможливлює використання фільтрувальних матеріалів та/чи сорбентів у певній сфері. У зв’язку з вищевикладеним, об’єктом даного дослідження став процес очистки води з використанням МПФ із знезаражуючими властивостями на основі модифікованих целюлозних волокон та природного сорбенту палигорскіт, якi можуть сорбувати механічні домішки, іони важких металів, ентеровiруси та бактерії.Встановлено, що зразки модифікованих матеріалів паперових фільтрувальних із найвищою щільністю та найменшою товщиною та зразки із найменшою щільністю та найбільшою товщиною мають більшу фільтраційну та сорбційну здатності у порівнянні із зразками з середніми значеннями цих технологічних параметрів.Набухання целюлозних волокон зменшує силу впливу композиційного складу досліджених зразків МПФ на їх фільтраційну здатність та збільшує силу впливу композиційного складу на сорбційну здатність цих МПФ.Встановлено, що найкращі технологічні характеристики мають зразки, до складу яких було введено близько 40 % фосфорного ефіру целюлози.Встановлено характер залежності швидкості процесу фільтрування від витрати очищуваної води, товщини, щільності та композиційного складу МПФ. Отримані математичні моделі представлені поліномом другого порядку та дозволяють враховувати не тільки технічні характеристики, але і вплив композиційного складу МПФ на швидкість процесу фільтрування очищуваної води. З досліджених параметрів найбільші сили впливу на швидкість процесу фільтрування при сталих тиску та концентрації забруднення мають відсотковий вміст сульфітної віскозної чи сульфатної біленої целюлози у папероутворюючій масі досліджених зразків та витрати очищуваної води. Запропоновані математичні моделі дозволяють також визначити необхідний композиційний склад для отримання МПФ з заданими властивостям

Pneumocystis pneumonia mimicking COVID-19

Background. The new coronavirus infection COVID-19 caused by a SARS-CoV-2 zoonotic beta-coronavirus has radically transformed the conventional concept of the immune systems participation in an infectious process. The successful application of anti-interleukin monoclonal antibodies and inhibitors of Janus kinases in COVID-19, traditionally contraindicated in infections, testifies that the immune response to the pathogen may be more dangerous than the infection itself. However, when prescribing the immunosuppressive therapy to COVID-19 patients, one should not forget that some interstitial pneumonias caused by opportunistic microflora, such as Pneumocystis Jirovecii, have similar clinical and radiological manifestations. Clinical case description. A 29-year old female patient was admitted to the infectious disease hospital with complaints of a febrile temperature, shortness of breath at rest, low-productive cough, pronounced weakness. She had been ill for 14 days, the SARS-CoV-2 RNA was detected at the pre-hospital stage. After the admission, a chest CT scan was performed showing a subtotal lung damage with the characteristic radiological manifestations of interstitial pneumonia in the form of ground glass opacity regions, presence of air traps, that was initially attributed to bilateral viral pneumonia (СТ-3/4). The subsequent examination confirming primary HIV infection and a sputum analysis positive for P. Jirovecii allowed us to establish a correct clinical diagnosis of pneumocystis pneumonia against the background of HIV infection and a mild COVID-19 course, administer a co-trimoxazole therapy and obtain a favorable outcome. Conclusion. This observation demonstrates the necessity of applying an individual approach to each patient admitted to a COVID hospital and performing a differential diagnosis, even when COVID-19 is confirmed by the laboratory work, in order not to miss other interstitial pneumonias, in particular, pneumocystis pneumonia appearing against the background on immunodeficiency

The District Heating in the Context of the Active Consumers Development in Smart Energy Systems

The paper defines the main factors of the smart energy systems that influence on the district heating. Noted increase in the regulatory impact of electric energy system on the district heating and increase in roles of the distribution and consumption of thermal energy. Urban population and other consumers of energy become equal partners of the utilities and acquire the status of "active" consumers. The heating supply companies need to develop a new model of management of heating regimes with dynamic synchronization with energy system and "active" consumers. One of the most important conditions of the achievement of the cost reduction, reliability and quality increase in community facilities is active consumer's behavior

Safety and efficacy of convalescent plasma for COVID-19: the preliminary results of a clinical trial

Background. The lack of effective etiotropic therapy for COVID-19 has prompted researchers around the globe to seekr various methods of SARS-CoV-2 elimination, including the use of convalescent plasma. Aim. The aim of this work was to study the safety and efficacy of the convalescence plasma treatment of severe COVID-19 using the plasma containing specific antibodies to the receptor binding domain (RBD) of SARS-CoV-2 S protein in a titer of at least 1:1000. Methods. A single-center, randomized, prospective clinical study was performed at the FRCC FMBA of Russia with the participation of 86 patients who were stratified in two groups. The first group included 20 critically ill patients who were on mechanical ventilation the second group included 66 patients with moderate to severe COVID-19 and with spontaneous respiration. The patients in the second group were randomized into two cohorts in a ratio of 2:1. In the first cohort (46 patients), pathogen-reduced convalescent plasma was transfused (twice, 320 ml each), in the second cohort (20 patients) a similar amount of non-immune freshly frozen plasma was transfused to the patients. Results. The use of plasma of convalescents in patients with severe COVID-19 being on mechanical ventilation does not affect the disease outcome in these patients. The mortality rate in this group was 60%, which corresponds to the average mortality of COVID patients on mechanical ventilation in our hospital. In the second group, clinical improvement was detected in 75% and 51%, for convalescent and non-immune plasma, respectively. Of the 46 people who received convalescent plasma, three patients (6.5%) were transferred to mechanical ventilation, two of them died. In the group receiving non-immune plasma, the need for mechanical ventilation also arose in three patients (15%), of which two died. The hospital mortality in the group of convalescent plasma was 4.3%, which is significantly lower than the average COVID-19 hospital mortality at our Center (6.73%) and more than two times lower than the hospital mortality in the control group (n=150), matched by age and by the disease severity. Conclusions. Thus, we demonstrated a relative safety of convalescent plasma transfusion and the effectiveness of such therapy for COVID-19 at least in terms of the survival of hospitalized patients with severe respiratory failure without mechanical ventilation. In the absence of bioengineered neutralizing antibodies and effective etiotropic therapy, the use of hyperimmune convalescent plasma is the simplest and most effective method of specific etiopathogenetic therapy of severe forms of COVID-19

Association between convalescent plasma treatment and mortality in COVID-19: a collaborative systematic review and meta-analysis of randomized clinical trials.

Funder: laura and john arnold foundationBACKGROUND: Convalescent plasma has been widely used to treat COVID-19 and is under investigation in numerous randomized clinical trials, but results are publicly available only for a small number of trials. The objective of this study was to assess the benefits of convalescent plasma treatment compared to placebo or no treatment and all-cause mortality in patients with COVID-19, using data from all available randomized clinical trials, including unpublished and ongoing trials (Open Science Framework, https://doi.org/10.17605/OSF.IO/GEHFX ). METHODS: In this collaborative systematic review and meta-analysis, clinical trial registries (ClinicalTrials.gov, WHO International Clinical Trials Registry Platform), the Cochrane COVID-19 register, the LOVE database, and PubMed were searched until April 8, 2021. Investigators of trials registered by March 1, 2021, without published results were contacted via email. Eligible were ongoing, discontinued and completed randomized clinical trials that compared convalescent plasma with placebo or no treatment in COVID-19 patients, regardless of setting or treatment schedule. Aggregated mortality data were extracted from publications or provided by investigators of unpublished trials and combined using the Hartung-Knapp-Sidik-Jonkman random effects model. We investigated the contribution of unpublished trials to the overall evidence. RESULTS: A total of 16,477 patients were included in 33 trials (20 unpublished with 3190 patients, 13 published with 13,287 patients). 32 trials enrolled only hospitalized patients (including 3 with only intensive care unit patients). Risk of bias was low for 29/33 trials. Of 8495 patients who received convalescent plasma, 1997 died (23%), and of 7982 control patients, 1952 died (24%). The combined risk ratio for all-cause mortality was 0.97 (95% confidence interval: 0.92; 1.02) with between-study heterogeneity not beyond chance (I2 = 0%). The RECOVERY trial had 69.8% and the unpublished evidence 25.3% of the weight in the meta-analysis. CONCLUSIONS: Convalescent plasma treatment of patients with COVID-19 did not reduce all-cause mortality. These results provide strong evidence that convalescent plasma treatment for patients with COVID-19 should not be used outside of randomized trials. Evidence synthesis from collaborations among trial investigators can inform both evidence generation and evidence application in patient care

First-in-human high-cumulative-dose stem cell therapy in idiopathic pulmonary fibrosis with rapid lung function decline

Previous phase I studies demonstrated safety and some beneficial effects of mesenchymal stem cells (MSCs) in patients with mild to moderate idiopathic pulmonary fibrosis (IPF). The aim of our study was to evaluate the safety, tolerability, and efficacy of a high cumulative dose of bone marrow MSCs in patients with rapid progressive course of severe to moderate IPF. Twenty patients with forced ventilation capacity (FVC) ≥40% and diffusing capacity of the lung for carbon monoxide (DLCO) ≥20% with a decline of both >10% over the previous 12 months were randomized into two groups: one group received two intravenous doses of allogeneic MSCs (2 × 10 cells) every 3 months, and the second group received a placebo. A total amount of 1.6 × 10 MSCs had been administered to each patient after the study completion. There were no significant adverse effects after administration of MSCs in any patients. In the group of MSC therapy, we observed significantly better improvement for the 6-minute walk distance in 13 weeks, for DLCO in 26 weeks, and for FVC in 39 weeks compared with placebo. FVC for 12 months in the MSCs therapy group increased by 7.8% from baseline, whereas it declined by 5.9% in the placebo group. We did not find differences between the groups in mortality (two patients died in each group) or any changes in the high-resolution computed tomography fibrosis score. In patients with IPF and a rapid pulmonary function decline, therapy with high doses of allogeneic MSCs is a safe and promising method to reduce disease progression. 8

SYSTEMATICS AND EVOLUTION OF HARES, KIN LEPUS (LAGOMORPHA, LEPORIDAE) IN PALEARCTIC

The object of investigation: the hares, the cranium, the dental system. The purpose of the work: revealing the evolution history and constructing the phylogenetic system of kin Lepus.First, using the important material, the intraspecies variation of the modern and placetocenous hares has been studied. The morphotypic approach to studying the variation has allowed to evaluate the phenetic distance between the species and populations. The new phylogenetic kin system for the Palearctic on the subspesies level has been offered. The new system of the kin can be used in the determinators of the country and the world theriofauna. The results of the investigation of the placetocenous hares can be used for the biostratigraphy and paleoecological reconstruction, and for the development of measures on the protection of the rare forms of hares. The field of application: the zoology, the paleontology, the stratigraphy of placetocene, the nature protectionAvailable from VNTIC / VNTIC - Scientific & Technical Information Centre of RussiaSIGLERURussian Federatio