Parameters of passive working bodies of potato digging machine

The major working housing of potato digging machines is a plowshare on which energy costs and the quality of potato digging depend. The examination aims to justify the parameters of the plowshare and the divider of the combined digging working body. The constructive scheme of a potato-digging machine with a combined digging working body, the results of theoretical studies on the substantiation of the primary parameters of the main and intermediate plowshares and the divider, are presented. A special laboratory installation was used to conduct experiments. During the experiments, dividers with different capture widths were made, and the angle of the plowshare installation to the horizon was changed. The degree of damage and loss of the tuber and the traction resistance of the plowshares were taken as evaluation criteria. The outcome of the experimental investigation to determine the parameters of the plowshare is presented. Based on theoretical studies, analytical dependencies, and mathematical models were obtained that allow determining the parameters of the plowshare and the divider of the potato digging machine. It was found that for intensive destruction of the tuberous formation with minimal energy consumption and uniform transportation, the width of the colter of the combined working housing must be 45 cm, the perspective of the plowshare razor solution 90°, the perspective of inclination of the plowshare to the skyline within 27-30°, the length of the plowshare 40 cm, the width of the divider should be 45 cm, its length 39 cm, the angle the solution is 60°, the angle of installation of the working surface to the horizon in the transversely vertical plane is 65° and the range from the toe of the intermediate plowshare to the divider is 32.6 cm

Обоснование параметров искусственной почвенной среды для лабораторного исследования изнашивания лезвия

For soil cultivation with the cutting tools of agricultural machines we can allocate three main types of shavings: shift, separation and continuous chip. The shift is most accurately expressed on sandy soils, a separation - on clay and loamy, continuous chip - on humid soils with the high content of clay particles. In field conditions researches of regularities of cutting edges wear are complicated because of heterogeneity of physic and mechanical properties of the soil and the changing climatic conditions. At laboratory modeling of soil conditions we can make experiments independent of weather and season. For development of the artificial soil and depend modeling of edges wear we considered conditions of creation of model with use mechanics of abrasive wear. Have allocated The major factors defining character and intensity of wear were allocated. The wearing-out ability of abrasive particles is defined by the radius of the curve of their sharp ledges. This radius depends on the particle size. The hardness of the soil influences wear of the cutting details and characterizes penetration into it of the cutting elements, and degree of fixedness of abrasive particles defines shaving type. We conseeder the soil as the abrasive environment with the particles which are in a condition of non-rigid fixing and have an opportunity to move relatively each other or to turn on itself under the influence of normal and tangential stress. Type of shaving when soil layer destruction depends on a ratio of the normal and tangential stress characterizing degree of fixedness of firm particles. We conducted researches of physic and mechanical properties of the artificial soil on the basis of quartz sand and paraffin. Injection of the petrolatum into structure of the artificial soil reduces the hardness and degree of fixedness of firm particles, but the ceresin increases these indicators. The mechanical structure was changed due to introduction of dust-like cement and replacement of fractions of abrasive particles. We manufactured blocks of the artificial soil, melting paraffin at a temperature of 85-90 degrees Celsius and filling up in it a firm phase. Researches make it possible to choose options of the artificial soil for studying of the main regularities of soil cutting elements.При обработке почвы режущими деталями сельхозмашин можно выделить три основных типа стружки: сдвиг, отрыв и сливная стружка. Сдвиг наиболее четко выражен на песчаных почвах, отрыв - на глинистых и суглинистых, сливная стружка - на почвах повышенной влажности с высоким содержанием глинистых частиц. В полевых условиях исследовать закономерности изнашивания почворежущих лезвий сложно из-за неоднородности физико-механических свойств почвы и изменяющихся климатических условий. При лабораторном моделировании почвенных условий можно проводить эксперименты вне зависимости от погоды и времени года. Для разработки искусственной почвы и моделирования износа лезвий рассмотрели условия построения модели исходя из механики абразивного изнашивания. Выделили основные факторы, определяющие характер и интенсивность изнашивания почворежущего лезвия. Отметили, что изнашивающая способность абразивных частиц определяется радиусом закругления их острых выступов, зависящего от размера частицы. Показали, что твердость почвы влияет на износ режущих деталей и характеризует проникновение в нее режущих элементов, а степень закрепленности абразивных частиц определяет тип стружки. Представили почву как абразивную среду с частицами, находящимися в состоянии нежесткого закрепления и имеющими возможность перемещаться относительно друг друга или поворачиваться вокруг своей оси под действием нормальных и касательных напряжений. Подтвердили положение о зависимости типа стружки при разрушении почвенного пласта от соотношения нормальных и касательных напряжений, характеризующих степень закрепленности твердых частиц. Провели исследования физико-механических свойств искусственной почвы на основе кварцевого песка и парафина. Для изменения ее свойств в состав искусственной почвы вводили вазелин, уменьшающий твердость и степень закрепленности твердых частиц, или церезин, увеличивающий эти показатели. Механический состав изменяли введением пылевидного цемента и заменой фракций абразивных частиц. Изготовили блоки искусственной почвы, расплавляя парафин при температуре 85-90 градусов Цельсия и засыпая в него твердую фазу. Провели исследования, позволившие выбрать варианты искусственной почвы для изучения основных закономерностей изнашивания почворежущих элементов

РАСПОЛОЖЕНИЕ ЛЕЗВИЯ НАКЛАДНОГО ДОЛОТА ПО ОТНОШЕНИЮ К НАПРАВЛЕНИЮ ДВИЖЕНИЯ ПАХОТНОГО АГРЕГАТА

An overlaid chisel of a compound ploughshare is the most loaded part which is important for operability of a ploughshare and  implementation of agrotechnical requirements for plowing depth.  Chisels of ploughshares are made by methods of stamping and  blanking with use of gas, laser or plasma machines. Parts from a  rolled strip are the most wearresisting. Сhisels with big difference on plowing depth between extreme points of an edge are the best for  heavy soils cultivation because of partial destruction of the soil  bottom layer. When light and medium soils plowing the difference of  depth between extreme points of an edge of a chisel is reduced for  decrease in traction resistance of a ploughshare. On light soils with  the hardness up to 2.7 MPa the plows equipped with ploughshares  with the chisels having the minimum difference on depth between extreme points of an edge have the minimum traction resistance. When difference raises up to 30 mm traction resistance increases on  average for 5.5 percent. This dependence is close to linear if  difference of depth varies from 10 to 30 mm. The overlaid chisels are recommended for ploughshares at cultivation of light and heavy soils by plows of general purpose. The angle between a chisel edge and a  furrow wall should to be direct, and the difference of depth between extreme points on the line crossing an edge and sides of the chisel should be in an interval of 15-20 mm.Накладное долото составного лемеха – наиболее нагруженная деталь, играющая существенную роль в обеспечении работоспособности лемеха и в выполнении  агротехнических требований по глубине вспашки. Долота лемехов изготавливают методом  штамповки, вырубки из прокатной полосы и вырезки из листа с применением газовых,  лазерных либо плазменных установок. Наилучшей производительностью отличаются детали  из прокатной полосы. Отметили, что на тяжелых почвах лучшие показатели имеют долота с  большим перепадом по глубине вспашки между крайними точками лезвия вследствие  частичного разрушения нарастающей почвенной подошвы. При вспашке легких и средних  почв перепад глубины между крайними точками лезвия долота уменьшают для снижения  тягового сопротивления лемеха. Установили, что на легких почвах твердостью до 2,7 МПа  минимальное тяговое сопротивление характерно для плугов, оснащенных лемехами с  долотами, имеющими минимальный перепад по глубине между крайними точками лезвия.  Доказали, что с увеличением перепада до 30 мм тяговое сопротивление возросло в среднем на 5,5 процента, причем повышение тягового сопротивления происходило по зависимости, близкой к линейной, в диапазоне перепада глубины от 10 до 30 мм. Выявили,  что на легких и тяжелых почвах для плугов общего назначения необходимо рекомендовать  к лемехам накладные долота. При этом угол между лезвием долота и стенкой борозды  должен быть прямым, а перепад по глубине установки лезвия долота между крайними точками на линии, пересекающей лезвие и боковые грани долота, должен находиться в интервале 15-20 мм

Повышение точности аэрофотосъемки с применением наземных контрольных точек

The authors showed that it is possible to quickly collect up-to-date information on the agricultural land condition using an unmanned aerial vehicle. It was noted that the use of ground control points increases the accuracy of project measurements, helps to compare the project post-processing results with the real measurements. (Research purpose) To compare the results of standard and high-precision post-processing of aerial survey data using ground control points. (Materials and methods) Aerial photography was carried out on a 1.1- hectare breeding field. The authors used DJI Matrice 200 v2 unmanned aerial vehicle with a GNSS L1/L2 receiver and a modified DJI X4S camera, five control points sized 50 × 50 centimeters and an EMLID Reach RS2 multi-frequency GNSS receiver. The results of scientific research into the use of ground control points during aerial photography were studied. (Results and discussion) It was found out that the error of georeferencing images obtained by an unmanned aerial vehicle without control points is significantly higher during the standard data processing compared to the high-precision one. The project error when using five control points is 3.9 times higher during the standard data processing. (Conclusions) It was shown that using ground control points it is possible to improve the project measurement accuracy, as well as compare the project post-processing results with the measurements on the ground. It was detected that the high-precision monitoring enables the use of fewer ground control points. It was found out that in order to obtain data with the accuracy of 2-4 centimeters in plan and height, at least 3 ground control points need to be used during the high-precision post-processing.Показали возможность оперативного сбора актуальной информации о состоянии сельскохозяйственных угодий с помощью беспилотного воздушного судна. Отметили, что использование наземных опорных точек повышает точность измерений в проекте, помогает сравнить результаты постобработки проекта с реальными измерениями. (Цель исследования) Сравнить результаты стандартной и высокоточной постобработки данных аэрофотосъемки с использованием наземных опорных точек. (Материалы и методы) Провели аэрофотосъемку на селекционном поле площадью 1,1 гектара. Использовали беспилотное воздушное судно DJI Matrice 200 v2 с приемником GNSS L1/L2 и модифицированной камерой DJI X4S, пять опорных точек размером 50 × 50 сантиметров и мультичастотный GNSS-приемник EMLID Reach RS2. Изучили результаты научных исследований по применению наземных опорных точек при проведении аэрофотосъемки. (Результаты и обсуждение) Определили, что погрешность геопривязки изображений, полученных посредством беспилотного воздушного судна, без опорных точек значительно выше при стандартной обработке данных по сравнению с высокоточной. Погрешность проекта при применении пяти опорных точек выше в 3,9 раза для стандартной обработки данных. (Выводы) Показали, что с помощью наземных опорных точек можно повысить точность измерений в проекте, а также сравнить результаты его постобработки с измерениями на местности. Определили, что высокоточный мониторинг позволяет обойтись меньшим количеством наземных опорных точек. Выявили, что для получения данных с точностью 2-4 сантиметра в плане и по высоте при высокоточной постобработке нужно использовать не менее 3 наземных опорных точек

Role of autoantibody in the pathogenesis of patients with atopic bronchial asthma

© 2015 Asian Network for Scientific. Bronchial Asthma is considered as the most spreading human chronic diseases. The diagnostic of the disease at its beginning is very difficult because the light forms of the disease can’t be diagnosed as the symptoms are not very well developed at the outbreak of the disease. The objective of this study was to correlate the climatic and geographic factors and the environmental conditions in the occurrence of Atopic Bronchial Asthma and other autoimmune phenomena, for example the prevalence of abzymes in the pathogenesis of Atopic Bronchial Asthma. In the present work, enzyme linked to immune sorbent assay method and the methods of electrophoresis in agarose gel were used. The results of our study showed the discovery of an excessive auto-antibodies to DNA in the blood vessels of patients with atopic bronchial asthma and there was a direct correlation dependence (r = 0.0005) between the level of auto-antibodies to DNA and the severity of the Atopic Bronchial Asthma. The detected auto-antibodies possess catalytic activity of DNA, enzymatic specificity which is associated with the degree of severity of disease. The auto antibodies in patients suffering from severe forms of Bronchial Asthma are specific for monofilament DNA and antibodies in the blood serum of the patients with the light form of asthma is heterogenic: besides antibodies with monofilament substratum, some specific antibodies with bi-filament DNA circulate. Therefore, in the serum of the patients suffering from Atopic Bronchial Asthma antibodies with Catalytic activity DNA was observed-that is abzymes. It was suggested that these “abzymes” maybe directly involved in the removal of debris produced by the metabolism of organism under physiological conditions. Considering all these facts, Abzymes can be regarded as serological markers of autoimmunity and needs to be tested while investigating autoimmunity especially in Atopic Bronchial Asthma and it may also serve as an additional criterion for the diagnosis of asthma even in the early stages and can also help in the evaluation of the effectiveness of the treatment

Prediction of clinical course in patients with diffuse coronary artery disease after coronary bypass surgery

Aim. To determine the incidence, predictors and develop a model for long-term risk stratification of ischemic events in patients with coronary artery disease after coronary bypass surgery.Material and methods. This retrospective study of the clinical course in patients with diffuse coronary artery disease (CAD) after coronary endarterectomy and bypass grafting surgery. A total of 232 patients were included, while long-term outcomes were assessed in 202 patients. Among them, complete data on clinical status were obtained from survivors (n=191). The median follow-up was 60 (interquartile range, 42; 74) months, while the minimum follow-up — 12 months, the maximum was 96 months. The primary composite endpoint reflecting the unfavorable course of CAD included coronary ischemic events (recurrent angina, myocardial infarction, repeat revascularization), while secondary endpoint — allcause mortality. The factors influencing the development of primary and secondary endpoints were studied.Results. An unfavorable CAD course was diagnosed in 39 patients (20,4%), while 11 deaths were recorded (5,4%). Univariate analysis demonstrated a significant role of prior myocardial infarction in the increase in mortality rate (p=0,029). Among the factors influencing the CAD course, no significant differences were obtained for any of them. A multivariate analysis was performed to identify a high-risk group for an unfavorable course of diffuse CAD. Independent predictors were identified, the most significant contribution of which was made by multifocal atherosclerosis (odds ratio (OR)=1,99, 95% confidence interval (CI), 0,93-4,21, p=0,072), low adherence to secondary prevention measures (OR=2,21, 95% CI, 0,86-6,89, p=0,128) and diabetes (OR=1,73, 95% CI, 0,79-3,72, p=0,162). Using the results obtained, a prognostic model with high specificity (64%) and moderate sensitivity (53%) was created.Conclusion. The highest probability of an unfavorable long-term course of diffuse CAD was noted in patients with diabetes, multifocal atherosclerosis, and low adherence to secondary prevention measures. The obtained results make it possible to identify a high-risk group in this cohort of patients, determine the reserve of secondary prevention measures and a direction of actions to improve outcomes

Localization and nature of radiation donor defects in the arsenic implanted CdHgTe films grown by MBE

By profiling the electrical parameters of the arsenic implanted CdHgTe films, grown by molecular bea

Novel SMAC-mimetics synergistically stimulate melanoma cell death in combination with TRAIL and Bortezomib

BACKGROUND: XIAP (X-linked inhibitor of apoptosis protein) is an anti-apoptotic protein exerting its activity by binding and suppressing caspases. As XIAP is overexpressed in several tumours, in which it apparently contributes to chemoresistance, and because its activity in vivo is antagonised by second mitochondria-derived activator of caspase (SMAC)/direct inhibitor of apoptosis-binding protein with low pI, small molecules mimicking SMAC (so called SMAC-mimetics) can potentially overcome tumour resistance by promoting apoptosis. METHODS: Three homodimeric compounds were synthesised tethering a monomeric SMAC-mimetic with different linkers and their affinity binding for the baculoviral inhibitor repeats domains of XIAP measured by fluorescent polarisation assay. The apoptotic activity of these molecules, alone or in combination with tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) and/or Bortezomib, was tested in melanoma cell lines by MTT viability assays and western blot analysis of activated caspases. RESULTS: We show that in melanoma cell lines, which are typically resistant to chemotherapeutic agents, XIAP knock-down sensitises cells to TRAIL treatment in vitro, also favouring the accumulation of cleaved caspase-8. We also describe a new series of 4-substituted azabicyclo[5.3.0] alkane monomeric and dimeric SMAC-mimetics that target various members of the IAP family and powerfully synergise at submicromolar concentrations with TRAIL in inducing cell death. Finally, we show that the simultaneous administration of newly developed SMAC-mimetics with Bortezomib potently triggers apoptosis in a melanoma cell line resistant to the combined effect of SMAC-mimetics and TRAIL. CONCLUSION: Hence, the newly developed SMAC-mimetics effectively synergise with TRAIL and Bortezomib in inducing cell death. These findings warrant further preclinical studies in vivo to verify the anticancer effectiveness of the combination of these agents

Разработка и технология изготовления почвообрабатывающих рабочих органов

Plow ploughshares of compound designs even more often appear to replace integral wedge-shaped ones. At the All-Russian research institute of mechanization of agriculture ploughshares with the bolt-on moving-forward tine are produced. The main material was the silicon manganic chromic steel. In the heat-treated state its ultimate resistance is more than 1580 MPa. A resource and reliability of a ploughshare are raised owing to increase in number of fixation holes for a tine from 2 to 4. The tine can be pushed forward in process of wear by bolts replacing with top on the lower holes in a tip. The curvilinear surface of front part of a ploughshare reduces a cutting angle in the direction from field to a furrow wall. A special stamp was designed and created. Its matrix and hob had surfaces of the set curvature. The detail heated to temperature of 900-920 degrees Celsius was stacked on a matrix, and the hob was pressed by means of a hydraulic press. Blades on a ploughshare body and on a tine were strengthened by hard alloy metal surfacing. The authors carried out a cycle of field tests in soil climatic conditions, the most characteristic for the central regions of the Russian Federation. Results of tests showed that on the soils optimum for plowing where the hardness of the soil did not exceed 2.5-3 MPa and the number of stony inclusions was minimum, the resource of test ploughshares by 2.5-2.8 times exceeded a resource of commercial ones and made 80-110 ha per a unit. On heavy clay and loamy soils, with the hardness up to 4 MPa and above, the resource of tast ploughshares reached 25-33 ha per a unit that also above commercial ones by 2.7-3.2 times which resource did not exceed 12-18 ha. On soils with quartz particles high content and stony inclusions breakages and deformation of ploughshares became the main reason for nonoperations. The mean life of an engineering prototypes made 8-10 ha per a ploughshare, at the commercial ones did not exceed 2.5 ha. Tests showed significant superiority of ploughshares with a bolt-on tine both on a resource, and on reliability.Плужные лемехи составных конструкций все чаще приходят на смену цельным долотообразным. Во Всероссийском научно-исследовательском институте механизации сельского хозяйства освоили производство лемехов с накладным выдвигающимся долотом. В качестве основного материала использовали кремне-марганцовистую хромистую сталь, имеющую в термообработанном состоянии предел прочности более 1580 МПа. Ресурс и надежность лемеха повышены вследствие увеличения числа крепежных отверстий для долота с 2 до 4. Долото можно выдвигать вперед по мере износа, переставляя болты с верхних на нижние отверстия в носке. Криволинейная поверхность лицевой части лемеха снижает угол резания в направлении от полевого к бороздному обрезу. Спроектировали и создали специальный штамп, матрица и пуансон которого имели поверхности заданной кривизны. Нагретую до температуры 900-920 градусов Цельсия деталь укладывали на матрицу, а пуансон прижимали с помощью гидравлического пресса. Лезвия на остове лемеха и долота упрочняли наплавкой твердым сплавом. Провели цикл полевых испытаний в почвенно-климатических условиях, наиболее характерных для центральных регионов Российской Федерации. Результаты испытаний показали, что на почвах, наиболее благоприятных для вспашки, где твердость почвы не превышала 2,5-3 МПа и количество каменистых включений было минимальным, ресурс опытных лемехов в 2,5-2,8 раза превысил ресурс серийных и составил 80-110 га на лемех. На тяжелых глинистых и суглинистых почвах, твердостью до 4 МПа и выше, ресурс опытных лемехов достигал 25-33 га на лемех, что также выше серийных в 2,7-3,2 раза, ресурс которых не превышал 12-18 га. Провели испытания и на почвах с большим содержанием кварцевых частиц и каменистых включений, где основной причиной отказов стали поломки и деформация лемехов. Средняя наработка у опытных образцов составила 8-10 га на лемех, у серийных - не превышала 2,5 га. Испытания показали значительное превосходство лемехов с накладным долотом как по ресурсу, так и по надежности

HIV-1 subtype A infection in a community of intravenous drug users in Pakistan

BACKGROUND: Data on the subtypes of HIV in a population help in predicting the potential foci of epidemic, tracking the routes of infection and following the patterns of the virus' genetic divergence. Globally, the most prevalent HIV infection is the HIV-1 subtype C. In Asia, predominant subtypes of HIV-1 are B, C, and CRF-01AE. During the last few years, HIV prevalence in Pakistan has taken the form of a concentrated epidemic in at least two high risk groups, namely, Intravenous Drug Users (IDUs) and Male Sex Workers (MSWs). Factors that have facilitated the proliferation of HIV infection include transmission through a large number of repatriates and needle-sharing intravenous drug users, unscreened blood transfusions, and sexual illiteracy. The HIV subtypes infecting Pakistani populations have not been explored to date. In this study, we analyzed HIV-1 subtypes from in a high-risk community of IDUs in Karachi, the largest city of Pakistan. METHODS: Samples were collected from 34 IDUs after their informed consent. In addition, the study subjects were administered a questionnaire regarding their sexual behavior and travel history. For HIV analysis, DNA was extracted from the samples and analyzed for HIV types and subtypes using subtype-specific primers in a nested polymerase chain reaction (PCR). The results from this PCR were further confirmed using the Heteroduplex Mobility Assay (HMA). RESULTS: We found HIV-1 subtype A in all the 34 samples analyzed. A few of the study subjects were found to have a history of travel and stay in the United Arab Emirates. The same subjects also admitted to having contact with commercial sex workers during their stay abroad. CONCLUSION: Our study therefore shows clade A HIV-1 to be prevalent among the IDUs in Karachi. As the prevalence of HIV in Pakistan continues to rise, more work needs to be done to track the infection, and to analyze the strains of HIV spreading through the country