14 research outputs found
Research of the second serve to lots of root crops
У статті наведено побудовані в результаті теоретичного аналізу процесу викопування коренеплодів розрахункові математичні моделі, які характеризують взаємозв’язок зміни секундної подачі викопаного вороху коренеплодів до еліпсних шнеків доочисника, або зміни необхідної пропускної здатності доочисника залежно від конструктивних параметрів лемешів вібраційних копачів і агрофізичних характеристик коренеплодів та експлуатаційних умов роботи коренезбиральної машини.It is resulted in the article, built as a result of theoretical analysis of process of excavation of root crops сcalculations mathematical models which characterize intercommunication of change of the second serve of dug up to the lots of root crops to ellipses of purifier or changes of necessary carrying capacity of purifier descriptions of root crops and operating terms of work of machine are resulted
Mathematical model of carrying capacity of purifier
У статті наведено математичну модель, яка характеризує взаємозв’язок необхідної пропускної здатності доочисника залежно від секундної подачі вороху або від умов і швидкості руху коренезбиральної машини, лінійних параметрів викопувального робочого органу та агрофізичних характеристик коренеплодів.A mathematical model, which characterizes intercommunication of necessary carrying capacity of purifier depending on the second serve to the lots or from terms and rate of movement of rootсollective machine, linear parameters of excavating working organ and agrоphysical descriptions of root crops, is resulted in the article
Approximate ab initio calculation of vibrational properties of hydrogenated amorphous silicon with inner voids
We have performed an approximate ab initio calculation of vibrational
properties of hydrogenated amorphous silicon (a-Si:H) using a molecular
dynamics method. A 216 atom model for pure amorphous silicon (a-Si) has been
employed as a starting point for our a-Si:H models with voids that were made by
removing a cluster of silicon atoms out of the bulk and terminating the
resulting dangling bonds with hydrogens.
Our calculation shows that the presence of voids leads to localized low
energy (30-50 cm^{-1}) states in the vibrational spectrum of the system. The
nature and localization properties of these states are analyzed by various
visualization techniques.Comment: 15 pages with 6 PS figures, to appear in PRB in December 199
Atrial remodelling comparison after maze-3 and cryo-maze procedures in combined cardiac interventions: a retrospective study
Background. The maze procedure aims to eliminate atrial fibrillation (AF), restore sinus rhythm (SR) and atrial contractility. However, conflicting evidence exists regarding the extent of atrial remodelling in various techniques, which directed the focus of our study.Objectives. An atrial remodelling comparison after a cut-and-sew maze-3 surgery and its biatrial cryo-maze modification using 2D echocardiography.Methods. The study is a retrospective uncontrolled interrupted two-cohort time-series trial, with patients selected by pseudorandomisation according to a normal sinus rhythm-maintaining AF surgery method. A total of 217 maze-3 and 113 cryo-maze combined cardiac interventions have been performed within 2012–2021. The interventions included valve repair, coronary artery bypass grafting and their combination. Due to differences in long-term follow-up, the cohorts were pseudorandomised to select by 50 restored vs. maintained sinus rhythm patients using a nearest-neighbour classifier coupled with logistic regression. Mean follow-up period was 6 (1–17) months. The patients had paroxysmal, persistent and longstanding persistent AF. Echocardiography values prior to and long-term post-surgery were further analysed to determine the atrial remodelling dynamics. Results. A statistically significant atrial volume reduction is evident in a long-term within-cohort comparison. Meanwhile, a statistically more pronounced remodelling is observed between cohorts after maze-3 procedure. The cohort 1 vs. 2 estimates are: mean left atrial volume 120/125 mL3 (p = 0.011), left atrial size in apical view 52/53 mm (p = 0.023), right atrial size in apical view 58/62 mm (p = 0.004), right atrial size in parasternal short axis view 43/45 mm (p = 0.004), right atrial area in apical 4-chamber view 25/28 cm2 (p = 0.007). Maintained atrial pacing patients had positive systolic atrial function recovery rates (E/A ratio increased to average 1.5) in the long-term in both comparison cohorts.Conclusion. Remodelling is biatrial after all the maze procedures compared. A more pronounced atrial volume reduction occurs after maze-3 surgery. The presence of sinus rhythm is facilitated by cardiac conduction leading to mechanical and electrical remodelling of the atria
Оценка сократимости и ремоделирования предсердий после процедуры «Лабиринт-3» при сочетанных вмешательствах на сердце
Highlights. The most important goal of atrial fibrillation surgical treatment is to eliminate the arrhythmia in order to restore atrial contractility and improve their transport function. Our study showed positive dynamics of atrial contractility and remodeling after the maze-3 procedure against the background of a regular heart rhythm restoration. The study of sinus rhythm predictors maintenance and recovery of atrial transport function will help to make patient selection more personified.Aim. Evaluation of atrial contractility and remodeling after the maze-3 procedure with combined interventions on the heart.Methods. The analysis of 217 combined surgical interventions was carried out, where a maze-3 was used to treat atrial fibrillation (AF). The operations were performed in our center from 2012 to 2016. Key points of the study: rhythm after surgery and echocardiographic control in the long-term follow-up in order to determine the dynamics of atrial contractility and volumes. The average follow-up period was 47 (1–100) months. 40 (18.4%) patients had paroxysmal, 38 (17.5%) persistent, 139 (64.1%) long-term persistent AF. The mean AF duration before surgery was 27.4 months (1–200 months). The indications for the maze-3 procedure were: ineffectiveness of antiarrhythmic therapy, the need to perform combined cardiac procedures. We used standard statistical research methods with one – and multivariate logistic regression.Results. In the long-term follow-up, sinus rhythm (SR) persists in 79% of patients. In the long-term follow-up, in this group of patients, the left atrial contractility was restored from 76% to 91%, while the biatrial contractility increased from 82 to 96%. Shorter AF duration before surgery was a positive predictor of SR recovery and atrial contractility (p = 0.005), while pulmonary artery pressure and patient age negatively affected these indicators (p = 0.041 and p = 0.038, respectively). The presence of SR early after surgery was not a significant predictor of AF freedom. At the same time, according to the long-term observations, patients maintaining a regular atrial heart rate had positive indicators of atrial systolic function restoration and a positive dynamics of a decrease in atrial volumes.Conclusion. SR and restoration of left atrial contractility are two interrelated goals of the maze procedure. The negative factors associated with the failure of surgical treatment of AF are increased pressure in the pulmonary artery, long-term AF before surgery, and the age of patients.Основные положения. Наиболее важная цель хирургического лечения фибрилляции предсердий – устранение аритмии для восстановления сократимости предсердий и улучшения их транспортной функции. В исследовании показана положительная динамика сократимости и ремоделирования предсердий после процедуры «Лабиринт-3» на фоне восстановления регулярного ритма сердца. Изучение предикторов удерживания синусового ритма и восстановления транспортной функции предсердий способствует более персонифицированному отбору пациентов.Цель. Оценка сократимости и ремоделирования предсердий после процедуры «Лабиринт-3» при сочетанных вмешательствах на сердце.Материалы и методы. Проведен ретроспективный анализ 217 сочетанных хирургических операций, при которых для лечения фибрилляции предсердий (ФП) применена техника «Лабиринт-3». Процедуры выполнены в ФГБУ «ФЦВМТ» Минздрава России (г. Калининград) с 2012 по 2016 г. Ключевые точки исследования: ритм сердца после операции и эхокардиографический контроль в отдаленные сроки наблюдения с целью определения динамики сократимости и объемов предсердий по ЭхоКГ-показателям. Средний период наблюдения составил 47 (1–100) мес. Мужчин – 145 (63%), средний возраст – 65 (45–82) лет. 40 (18,4%) пациентов имели пароксизмальную, 38 (17,5%) – персистирующую, 139 (64,1%) – длительно персистирующую форму ФП. Средняя продолжительность ФП до операции составила 27,4 (1–200) мес. Показаниями для выполнения процедуры «Лабиринт-3» являлись неэффективность антиаритмической терапии, необходимость сочетанных процедур на сердце. Применяли стандартные статистические методы исследования с проведением одно- и многофакторной логистической регрессии.Результаты. В отдаленные сроки наблюдения синусовый ритм сохранялся у 79% пациентов. Также у этой группы больных зарегистрировано восстановление сократимости левого предсердия с 76 до 91%, в то время как биатриальная сократимость увеличилась с 82 до 96%. Меньшая длительность ФП до операции являлась положительным предиктором восстановления СР и сократимости предсердий (р = 0,005), в то время как давление в легочной артерии и возраст пациентов отрицательно влияли на данные показатели (р = 0,041 и р = 0,038, соответственно). Наличие СР в ранние сроки после операции не являлось значимым предиктором свободы от ФП. При этом больные с удерживанием регулярного предсердного ритма сердца, по данным долговременных наблюдений, имели положительные показатели восстановления систолической функции предсердий и динамику уменьшения их объемов.Заключение. Синусовый ритм и восстановление сократимости предсердий – две взаимосвязанные цели процедуры «Лабиринт». Негативными факторами, ведущими к неуспеху хирургического лечения ФП, являются повышенное давление в легочной артерии, длительно существующая ФП до операции и старший возраст пациентов
Ways to develop brands and PR management of tourism enterprises with a focus on national markets
The subject of the research is theoretical, methodological and practical
approaches to the peculiarities of the formation and use of new products and brands,
PR-management technologies in the development strategies of tourism enterprises
with a focus on national markets and domestic consumers. The purpose of the work is
to determine the features and suggest ways to form and use new products and brands,
PR-management technologies in the development strategies of tourism enterprises
with a focus on national markets and domestic consumers, domestic tourism in the
context of global restrictions on the movement of people and international tourism
activities. The methodological basis of the article is both General scientific and
special methods of scientific knowledge. Monographic and historical methods were
used in determining the content of tourism products and brands and their evolution;
system-structural analysis and synthesis in justifying the types of brands (travel
companies, places or destinations, types of tourism and recreation, etc.), advertising
and PR-management tools with their promotion; statistical and economic,
mathematical modeling and programming in the development of opportunities to
attract new products and brands, PR management in marketing strategies for the
development of tourism enterprises and rural green tourism enterprise
Symulacja parametrów projektowych kubka udojowego o przedłużonej żywotności
Čėsna J., Medvedskyi O., Postol Y., Kukharets V., Zayets M., Hrudovij R., Pantsyr Yu., Zarajczyk J., Zbigniew D. Simulation of design parameters of a milking cup with an extended service life. Scientific Journal Agricultural Engineering. 2022. Vol. 26. No.1. PP. 243 -252.EN: Modern milking machines need some additional studies to meet the requirements
as to milking equipment. An imperfect design of a teatcup results in an incomplete
milking of cows. The availability of devices for milk flow stimulation promotes
an increase in a cow milk yielding capacity. But here arises a problem of an uncontrolled axial motion of a teatcup on a teat. As a result, a full milkflow is reduced, particularly at the final stages of milking. There is an effect of an increase
in an inner diameter of a liner barrel, which causes that teatcups fall down.
A scientific problem of the mitigation of some negative developments with the
view to improve the efficiency of a teatcup arises. In a teatcup shell a liner is in
a detended position during milking and resting periods. Thus, it under constant
stretching. It results in a loss of elasticity irrespective of the material, as well as
in reduction ofthe period of service maintenance. The use of a device for supporting a liner which is in a stretched state only during the milkflow, will result in an
increase of a teatcup efficiency. The suggested automatic pneumatic mechanism
releases a liner from the load during the resting period. The dependence of a tension force of a liner from the surface area of an annular membrane has been established. It has been proven that the membrane surface of 0.00065 m2 provides
tension for a mechanism performance irrespective of operating vacuum pressure.
The regression equation which connects geometrical parameters of an operating
system with the efforts directed at the opening of a leading membrane has been
received. A suitability of operation of using a pneumatic tightening device has
been substantiated. An insignificant axial motion of a liner during a cycle of milking creates a stimulating effect. As a result, a completeness of miliking increases
by 3-8%. PL: Współczesne maszyny udojowe wymagają prowadzenia dalszych badań, aby sprostać
wymaganiom sprzętu udojowego. Nieidealny project kubka udojowego wpływa na niezupełny wydój
krów. Dostępność urządzeń do stymulacji przepływu mleka zwiększa wydajność udoju. Jednak, pojawia się problem niekontrolowanego ruchu osiowego kubka udojowego na strzyku krowy. W rezultacie,
przepływ mleka jest zmniejszony, szczególnie na końcowych etapach udoju. Dochodzi do zwiększenia
wewnętrznej średnicy gumy strzykowej co powoduje odpadanie kubków udojowych. Pojawia się kwestia złagodzenia niektórych negatywnych skutków aby ulepszyć wydajność kubków udojowych. W
kubku udojowym, guma strzykowa znajduje się w pozycji odprężenia podczas dojenia i spoczynku.
Dlatego podlega ciągłemu rozciąganiu. Powoduje to zmniejszenie elastyczności bez względu na materiał a także skrócenie okresu serwisowego. Zastosowanie urządzenia do potrzymania gumy, która znajduje się w stanie rozciągnięcia tylko podczas przepływu mleka, spowoduje zwiększenie wydajności
kubka udojowego. Zaproponowany automatyczny mechanizm pneumatyczny zwalnia gumę od obciążenia podczas okresu spoczynku. Ustalono zależność siły napięcia gumy od powierzchni membrany
pierścieniowej. Udowodniono, że powierzchnia membrany 0.00065 m2
dostarcza napięcia mechanizmowi bez względu na podciśnienie robocze. Otrzymano równanie regresji, które łączy parametry geometryczne systemu roboczego z wysiłkiem skierowanym na otwarcie membrany. Potwierdzono odpowiedniość działania przy zastosowaniu pneumatycznego urządzenia zacieśniającego. Nieznaczący ruch
osiowy gumy podczas dojenia stwarza efekt stymulujący. W rezultacie kompletność udoju zwiększa
się o 3-8%
A heart-specific CD4+ T-cell line obtained from a chronic chagasic mouse induces carditis in heart-immunized mice and rejection of normal heart transplants in the absence of Trypanosoma cruzi.
Submitted by Ana Maria Fiscina Sampaio ([email protected]) on 2012-10-02T20:59:07Z
No. of bitstreams: 1
Ribeiro-Dos_Santos R A heart specific CD4+ T-cell....pdf: 365996 bytes, checksum: 63005200e720e052c9d7923012979eca (MD5)Made available in DSpace on 2012-10-02T20:59:07Z (GMT). No. of bitstreams: 1
Ribeiro-Dos_Santos R A heart specific CD4+ T-cell....pdf: 365996 bytes, checksum: 63005200e720e052c9d7923012979eca (MD5)
Previous issue date: 2001Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilFundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilUniversidade de São Paulo. Instituto de Ciências Biomédicas. Departamento de Imunologia. São Paulo, SP, BrasilFundação Oswaldo Cruz. Farmanguinhos. Rio de Janeiro, RJ, BrasilFundação Oswaldo Cruz. Farmanguinhos. Rio de Janeiro, RJ, BrasilFundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilFundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilTo study the role of autoreactive T cells in the pathogenesis of cardiomyopathy in Chagas' disease, we generated a cell line by repeated in vitro antigenic stimulation of purified splenic CD4+ T lymphocytes from a chronically Trypanosoma cruzi-infected mouse. Cells from this line were confirmed to be CD4+ CD8- and proliferated upon stimulation with soluble heart antigens from different animal species, as well as with T. cruzi antigen, in the presence of syngeneic feeder cells. In vitro antigen stimulation of the cell line produced a Th1 cytokine profile, with high levels of IFNgamma and IL-2 and absence of IL-4, IL-5 and IL-10. The cell line also terminated the beating of fetal heart clusters in vitro when cocultured with irradiated syngeneic normal spleen cells. In situ injection of the cell line into well established heart transplants also induced the cessation of heart beating. Finally, adoptive transfer of the cell line to heart-immunized or T. cruzi-infected BALB/c nude mice caused intense heart inflammation
Revealing New Patterns in Resourcesaving Processing of Chromiumcontaining Ore Raw Materials by Solidphase Reduction
The physical and chemical properties of products from the carbon-thermal reduction of oxide chromo-containing ore raw materials have been investigated. This is necessary to determine the parameters that reduce the loss of Cr in the processing of ore materials and the use of metallized chromium doping additives in steelmaking. It has been determined that the increase in processing temperature from 1,250 K to 1,450 K led to an increase in the manifestation of Cr23C6 and (Cr, Fe)7C3. In this case, the diffraction maxima of Cr2O3 corresponded to the trend of weakening and, having been treated at 1,450 K, had a residual character. Cr3C2 on the diffractograms was only evident after processing at 1,250 K. The phase of the metallic Cr was traced in the samples after processing at 1,350 K and 1,450 K with the increased intensity of manifestation when the heating temperature rose. It has been determined that the microstructure of reduction products is heterogeneous with the presence of particles of different sizes and chemical compositions. The increase in the reduction temperature from 1,250 K to 1,350 K and 1,450 K and the development of reduction processes were accompanied by particle sintering with the formation of a spongy microstructure. We have detected regions that characterized inclusions and the phases where Cr content amounted to 65.10 % by weight, Fe ‒ to 16.13 % by weight. Some local areas with particles with a relatively high content of ore impurities and carbon have also been found. It follows from the results of our study that the most acceptable temperature for reduction is 1,450 K. In this case, the reduction is ensured with a predominance in the phase composition of the metal Cr and carbides (Cr, Fe)7C3 and Cr23C6 relative to the oxide component of Cr2O3. In this case, the lower residual carbon content was due to the higher efficiency of the reducer compared to other temperature regimes.The spongy microstructure allows for a Faster dissolution compared to standard ferroalloys, thereby reducing the duration of smeltin
A vaccine against S. pyogenes: design and experimental immune response
Streptococcus pyogenes causes severe invasive infections: the post-streptococcal sequelae of acute rheumatic fever (RF) and rheumatic heart disease (RHD), acute glomerulonephritis, and uncomplicated pharyngitis and pyoderma. Efforts to produce a vaccine against S. pyogenes began several decades ago, and different models have been proposed. Here, we describe the methodology used in the development of a new vaccine model, consisting of both T and B protective epitopes constructed as synthetic peptides and recombinant proteins. Two adjuvants were tested in an experimental inbred mouse model: a classical Freund`s adjuvant and a new adjuvant (AFCo1) that induces mucosal immune responses and is obtained by calcium precipitation of a proteoliposome derived from the outer membrane of Neisseria meningitides B. The StreptInCor vaccine epitope co-administrated with AFCo1 adjuvant induced mucosal (IgA) and systemic (IgG) antibodies as preferential Th1-mediated immune responses. No autoimmune reactions were observed, suggesting that the vaccine epitope is safe. (c) 2009 Elsevier Inc. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)""Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)"" from BrazilConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq