Расчет шага почвообрабатывающей фрезы с зубцеобразной формой

The high energy intensity associated with rotary tillage of soil serves as a deterrent for its widespread use. Rotary tillers are used in cases when there are no alternatives as to the soil quality, especially when machining hard and sod-covered soils. The authors have described new modernized rotary tillers of a serrated type and considered the optimal location of knives relative to the drum. (Research purpose) To determine the relationships for calculating the pitch of a serrated-type rotary tiller for soil preparation before potato planting. (Materials and methods) The authors have noted that currently, there are no methods for selecting the main parameters and operation modes of serrated-type rotary tillers. The research has proved that a new approach is required for selecting the working surface profile of the rotary tiller knife in order to reduce the energy consumption of tillage and improve its quality. The authors have used mathematical and graphical calculations to determine the optimal pitch of the tiller foot. (Results and discussion) The paper presents an expression for determining the amount of soil loosening during the operation of rotary tillers. It has been calculated that an increase in the tillage depth from 0.10 to 0.15 meters results in an increase in the pitch of a tiller foot from 0.04 to 0.06 meters and the optimal value is 0.05 meters. For approximate engineering calculations, it has been assumed that the optimal parameter of a foot pitch is 0.25-0.45 of the knife loading value. (Conclusions) It has been found that the number of knives in one section and the operating width of a knife do not affect the optimal tooth pitch. It has been determined that this indicator linearly depends on the depth of tillage: as it increases by 0.05 meters, the optimal foot step increases by 0.025 meters. It has been shown that as the working speed of the rotary tiller increases, specific energy consumption required for the treatment of a furrow slice decreases, and the efficiency of soil tillage improves.Высокая энергоемкость фрезерования почв служит сдерживающим фактором их широкого применения. Фрезы применяют в тех случаях, когда нет альтернативы по качеству обработки, особенно тяжелых и задернелых почв. Показали, что модернизированные почвообрабатывающие фрезы имеют зубцеобразную форму. Рассмотрели вопросы оптимального расположения ножей относительно барабана. (Цель исследований) Получить зависимости для расчета шага зубцеобразной фрезы почвообрабатывающей машины для предпосадочной обработки почвы перед посадкой картофеля. (Материалы и методы) Отметили отсутствие методик при выборе основных параметров и режимов работы почвообрабатывающих фрез с зубцеобразной формой. Подтвердили необходимость нового подхода в выборе профиля рабочей поверхности ножа фрезы с целью уменьшения энергоемкости фрезерования и улучшения качества обработки. Использовали математические и графические расчеты для определения оптимального шага ступни. (Результаты и обсуждение) Представили выражение для определения объема рыхления почвы при работе почвообрабатывающих фрез. Рассчитали, что с увеличением глубины обработки почвы от 0,10 до 0,15 метра шаг ступни повышается с 0,04 до 0,06 метра и оптимально составляет 0,05 метра. Для ориентировочных инженерных расчетов приняли, что оптимальный  параметр шага ступни равен 0,25-0,45 от значения подачи на нож. (Выводы) Установили, что количество ножей в одной секции и ширина захвата ножа не влияют на величину оптимального шага зубьев. Определили, что этот показатель линейно зависит от глубины обработки почвы: с ее увеличением на 0,05 метра оптимальный шаг ступни возрастает на 0,025 метра. Показали, что с увеличением рабочей скорости фрезы уменьшаются удельные затраты энергии на обработку пласта, а эффективность обработки почвы улучшается

Nomenclatural standards and genetic passports of potato cultivars bred at the Leningrad Research Institute for Agriculture “Belogorka”

In the present paper, the potato cultivars bred at the Leningrad Research Institute for Agriculture “Belogorka”, were taken as an example for demonstrating the results of elaboration of methodological approaches that are currently developed at the N.I. Vavilov Institute of Plant Genetic Resources (VIR) for the preparing of nomenclatural standards and their genotyping. In 2018, joint research of VIR scientists and breeders from the Leningrad Research Institute for Agriculture “Belogorka” began in the field of preparing nomenclatural standards for potato cultivars bred at this institute. Nomenclatural standards were prepared according to the ‘International Code of Nomenclature for Cultivated Plants’. Plant material for herbarium specimens was collected in the experimental field of the “Belogorka” Institute in 2018 by cultivar authors and handed over to the VIR Herbarium of cultivated plants, their wild relatives and weeds (WIR). The plant material included stems with inflorescences and later - tubers of 21 cultivars which were bred at the “Belogorka” Institute. Two precultivars undergoing State variety testing and three breeding clones were also included in this study. Just before herbarium preparation, the obtained plant material was photographed, plant morphological characters described, and the results compared with the description given in such official documents as the “Cultivar Questionnaireˮ and “Description of selection achievementˮ. The nomenclatural standards of 21 cultivars registered in the VIR Herbarium Database and transferred for conservation to the VIR herbarium, are published in this paper. Before herbarium preparation, the plant material was sampled for DNA extraction and subsequent genotyping and molecular screening. The genetic passports include information about the polymorphism of 10 chromosome-specific microsatellite loci, as well as the data on the presence/absence of diagnostic fragments of 12 markers of the 11 R-genes conferring resistance to diseases and pests, and for some cultivars – the information about their cytoplasm type. These genetic passports are valuable not only because different types of DNA markers were used in their preparing (SSR, SCAR and CAPS markers of the R genes; markers specific to different loci of the nuclear and organelle genomes), but first of all because of the material itself, as the DNA samples were isolated from the plants with the assigned status of nomenclatural standard for each particular cultivar. Based on the genetic passports data, trueness to type of the “Belogorka” cultivar samples obtained from various sources was verified

Burst wave lithotripsy – the new evolution stage of extracorporeal shock-wave lithotripsy

Urolithiasis is currently one of the most urgent problems in the world. Every eleventh worldwide inhabitant suffers from this disease. Previously, the only way to get rid of kidney stones and the urinary tract was open surgery, which was characterized by high trauma. Over the past decades, the development of technologies has made a significant contribution to the development of new methods of urolithiasis treatment. One of these methods is extracorporeal shock wave lithotripsy (ESWL). The first lithotripter Dornier HM-1 was produced in 1980. Subsequent models have got many changes, both in terms of ergonomics and power. The researchers noticed that the efficiency of stone crushing in the Dornier HM-1 lithotripter was higher than in newer models since the lower power provided the less intensive formation of cavitation bubbles that prevent the effective transit of subsequent waves through the stone. Nowadays, a new method of remote stone crushing is being developed based on low-amplitude high-frequency technology combined with ultrasonic propulsion, which is the main difference from traditional shock-wave lithotripters. The new technology of stone crushing is called «burst wave lithotripsy» (BWL). Currently, the data have been obtained that this method is more effective in terms of crushing quality and less traumatic

International alliance of Urolithiasis (IAU) guideline on percutaneous nephrolithotomy

The International Alliance of Urolithiasis (IAU) would like to release the latest guideline on percutaneous nephrolithotomy (PCNL) and to provide a clinical framework for surgeons performing PCNL. These recommendations were collected and appraised from a systematic review and assessment of the literature covering all aspects of PCNLs from the PubMed database between January 1, 1976, and July 31, 2021. Each generated recommendation was graded using a modified GRADE methodology. The quality of the evidence was graded using a classification system modified from the Oxford Center for Evidence-Based Medicine Levels of Evidence. Forty-seven recommendations were summarized and graded, which covered the following issues, indications and contraindications, stone complexity evaluation, preoperative imaging, antibiotic strategy, management of antithrombotic therapy, anesthesia, position, puncture, tracts, dilation, lithotripsy, intraoperative evaluation of residual stones, exit strategy, postoperative imaging and stone-free status evaluation, complications. The present guideline on PCNL was the first in the IAU series of urolithiasis management guidelines. The recommendations, tips and tricks across the PCNL procedures would provide adequate guidance for urologists performing PCNLs to ensure safety and efficiency in PCNLs

Oscillations and waves in solar spicules

Since their discovery, spicules have attracted increased attention as energy/mass bridges between the dense and dynamic photosphere and the tenuous hot solar corona. Mechanical energy of photospheric random and coherent motions can be guided by magnetic field lines, spanning from the interior to the upper parts of the solar atmosphere, in the form of waves and oscillations. Since spicules are one of the most pronounced features of the chromosphere, the energy transport they participate in can be traced by the observations of their oscillatory motions. Oscillations in spicules have been observed for a long time. However the recent high-resolutions and high-cadence space and ground based facilities with superb spatial, temporal and spectral capacities brought new aspects in the research of spicule dynamics. Here we review the progress made in imaging and spectroscopic observations of waves and oscillations in spicules. The observations are accompanied by a discussion on theoretical modelling and interpretations of these oscillations. Finally, we embark on the recent developments made on the presence and role of Alfven and kink waves in spicules. We also address the extensive debate made on the Alfven versus kink waves in the context of the explanation of the observed transverse oscillations of spicule axes

Применение квантовых электронных устройств в периоперационном периоде у больных при ампутациях нижних конечностей

The authors present their experience in applying quantum electronic devices in patients undergoing lower limb amputations.Object. To develop a technique for potentiating the traditional multimodal anesthesia by optoelectronic devices with wavelength 650 nm (red range) and 470 nm (blue range) (manufactured in Russia) in amputation of lower extremities.Material and methods. Multimodal anesthesia with quantum electronic devices was performed in 48 patients (11 women and 37 men) aged 68–89 and having comorbidities. In the main group, for contact LED irradiation portable semiconductor LED device AFS к-630/670 emitting in red range with wavelength 650 ± 20 nm and portable AFS device emitting in blue range with wavelength 470 ± 10 nm and power 30 mW at the end of surgery were used. The above mentioned devices were made in the form of bracelets for non-invasive and non-contact application in the multimodal anesthesia during amputations of lower extremities. In the comparison group, multimodal anesthesia was not potentiated by contact LED irradiation.Results. The discussed Russian bracelets emitting in red and blue bands of the spectrum during amputation of lower extremities promoted the decrease of narcotic dosage (Fentanyl) during general multimodal anesthesia. In the main group, cardiac index increased at the end of surgery, and the total peripheral vascular resistance decreased if to compare to baseline values. In the comparison group, cardiac index increased somewhat less if to compare to baseline values, and the total peripheral vascular resistance decreased somewhat less if to compare to baseline values.Conclusion. The discussed bracelets emitting in red range (650 nm) which were applied during surgical interventions for the amputation of lower extremities and bracelets emitting in blue range (470 nm) which were applied at the end of surgery reduce the dose of narcotic preparations (Fentanyl) as well as stabilize hemodynamic parameters during surgery. Besides, in the immediate postoperative period, patients who survived amputation of lower extremities and in who the abovementioned bracelets were used do not require additional narcotic painkillers after amputation.В статье представлены результаты использования квантовых электронных устройств у пациентов при ампутациях нижних конечностей.Цель исследования – разработка методики потенцирования оптоэлектронными устройствами традиционной мультимодальной анестезии в области красного 650 нм и синего 470 нм диапазонов действия при ампутациях нижних конечностей.Материалы и методы исследования. Мультимодальная анестезия с применением квантовых электронных устройств была проведена у 48 пациентов (11 женщин и 37 мужчин) в возрасте от 68 до 89 лет с сопутствующими заболеваниями. Контактное светодиодное воздействие осуществляли в основной группе портативным полупроводниковым светодиодным аппаратом АФС к-630/670 в красном диапазоне действия с длиной волны 650 ± 20 нм и портативным аппаратом АФС в синем диапазоне действия с длиной волны 470 ± 10 нм мощностью 30 мВт в конце оперативного вмешательства. Устройства выполнены в виде браслетов на руку с целью неинвазивного бесконтактного применения, они использовались во время мультимодальной анестезии при ампутациях нижних конечностей. В группе сравнения мультимодальная анестезия не потенцировалась контактным светодиодным воздействием.Результаты исследования. Использование российских браслетов в красном и синем диапазонах действия во время проведения ампутаций нижних конечностей способствовало снижению дозы наркотических средств (фентанила) во время общей мультимодальной анестезии. В основной группе показатель сердечного индекса увеличивался в конце оперативного вмешательства, общее периферическое сосудистое сопротивление уменьшалось по сравнению с исходными значениями. В группе сравнения сердечный индекс увеличивался несколько меньше по сравнению с исходными данными, а общее периферическое сосудистое сопротивление также уменьшалось по сравнению с исходными данными.Заключение. Использование квантовых электронных устройств во время проведения оперативных вмешательств при ампутациях нижних конечностей позволяет снизить дозу наркотического препарата (фентанила) и стабилизировать гемодинамические показатели во время оперативного вмешательства. Кроме того, в ближайшем послеоперационном периоде не требуется дополнительное введение наркотических обезболивающих средств у пациентов с ампутациями нижних конечностей

Electronic properties and phase transitions in low-dimensional semiconductors

We present the first review of the current state of the literature on electronic properties and phase transitions in TlX and TlMX2 (M = Ga, In; X = Se, S, Te) compounds. These chalcogenides belong to a family of the low-dimensional semiconductors possessing chain or layered structure. They are of significant interest because of their highly anisotropic properties, semi- and photoconductivity, non-linear effects in their I-V characteristics (including a region of negative differential resistance), switching and memory effects, second harmonic optical generation, relaxor behavior and potential applications for optoelectronic devices. We review the crystal structure of TlX and TlMX2 compounds, their transport properties under ambient conditions, experimental and theoretical studies of the electronic structure, transport properties and semiconductor-metal phase transitions under high pressure, and sequences of temperature-induced structural phase transitions with intermediate incommensurate states. Electronic nature of the ferroelectric phase transitions in the above-mentioned compounds, as well as relaxor behavior, nanodomains and possible occurrence of quantum dots in doped and irradiated crystals is discussed.Comment: 70 pages, 38 figure

Лечение пациентов с гнойно-некротическими ранами с использованием внутривенного лазерного облучения крови (405 нм)

Objective: to analyze the effectiveness of purulent-necrotic wounds management using intravenous laser irradiation of blood (405nm). Materials and methods. Object of study – patients with purulent-necrotic wounds. Clinical studies and analysis of the intravenous laser blood irradiation (405 nm) effect on the wound healing process and on the healing speed of purulent soft tissues wounds in patients with type 2 diabetes mellitus were carried out. Results. It was found that the use of intravenous laser blood irradiation (405 nm) is a highly effective method for the treatment of purulent soft tissues wounds, which allows to reduce the number of complications and shorten the time for complete epithelization of purulent wounds by 7–10 days compared with traditional treatment. Цель исследования: анализ эффективности методики лечения больных гнойно-некротическими ранами с использованием внутривенного лазерного облучения крови (405 нм). Материалы и методы исследования. Объект исследования – пациенты с гнойно-некротическими ранами. В процессе работы проводили клинические исследования и анализ влияния внутривенного лазерного облучения крови (405 нм) на течение раневого процесса и на скорость заживления гнойных ран мягких тканей больных сахарным диабетом II типа. Результаты исследования. Установлено, что использование внутривенного лазерного облучения крови (405 нм) является высокоэффективным методом лечения гнойных ран мягких тканей, позволяющим уменьшить количество осложнений и сократить сроки полной эпителизации гнойных ран на 7–10 суток по сравнению с традиционным лечением.