130 research outputs found

    Grape selection for resistance to biotic and abiotic environmental factors

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    Most of the viticultural regions of the USSR are located under conditions of limiting biotic and abiotic factors, with frosts, drought, fungal diseases, phylloxera, mites, grape berry moths and some others being of primary importance. The main breeding organizations have been creating for more than 40 years new table and wine cultivars with complex resistance according to long-term programs. These cultivars are own-rooted and capable of wintering in outdoor culture with a limited amount of spray treatments, if any. In crossing, Amur grape and its hybrids, cultivars Seibel and Seyve Villard and some others are used as donors of resistance. Using biophysical and cytoembryological methods, gametes are treated with physical and chemical mutagenic factors in order to increase the variability range of F(1) seedlings, aiming at higher efficiency of selection. The process of selection is accelerated if seedlings are grown hydroponically. Analysis of the F(1) hybrid population determines the nature of the inheritance of valuable agricultural characters and the selection of pairs. The in vitro method is used when seedlings are grown from non-vital seeds, callus embryoids and in accelerated propagation of valuable genotypes providing virus and bacteria elimination. More than 50 cultivars with complex resistance have been bred during 35 years. More than 10 of them have been recommended for culture (Moldova, Lyana, Vostorg, Sukholimanski biely, Pervenets Magaracha, and others), while the remainder are being tested in different viticultural regions of the Soviet Union

    New classes of exact solutions of three-dimensional Navier-Stokes equations

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    New classes of exact solutions of the three-dimensional unsteady Navier-Stokes equations containing arbitrary functions and parameters are described. Various periodic and other solutions, which are expressed through elementary functions are obtained. The general physical interpretation and classification of solutions is given.Comment: 11 page

    Lie group analysis of a generalized Krichever-Novikov differential-difference equation

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    The symmetry algebra of the differential--difference equation u˙n=[P(un)un+1un1+Q(un)(un+1+un1)+R(un)]/(un+1un1),\dot u_n = [P(u_n)u_{n+1}u_{n-1} + Q(u_n)(u_{n+1}+u_{n-1})+ R(u_n)]/(u_{n+1}-u_{n-1}), where PP, QQ and RR are arbitrary analytic functions is shown to have the dimension 1 \le \mbox{dim}L \le 5. When PP, QQ and RR are specific second order polynomials in unu_n (depending on 6 constants) this is the integrable discretization of the Krichever--Novikov equation. We find 3 cases when the arbitrary functions are not polynomials and the symmetry algebra satisfies \mbox{dim}L=2. These cases are shown not to be integrable. The symmetry algebras are used to reduce the equations to purely difference ones. The symmetry group is also used to impose periodicity un+N=unu_{n+N}=u_n and thus to reduce the differential--difference equation to a system of NN coupled ordinary three points difference equations

    Lie symmetry analysis and exact solutions of the quasi-geostrophic two-layer problem

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    The quasi-geostrophic two-layer model is of superior interest in dynamic meteorology since it is one of the easiest ways to study baroclinic processes in geophysical fluid dynamics. The complete set of point symmetries of the two-layer equations is determined. An optimal set of one- and two-dimensional inequivalent subalgebras of the maximal Lie invariance algebra is constructed. On the basis of these subalgebras we exhaustively carry out group-invariant reduction and compute various classes of exact solutions. Where possible, reference to the physical meaning of the exact solutions is given. In particular, the well-known baroclinic Rossby wave solutions in the two-layer model are rediscovered.Comment: Extended version, 24 pages, 1 figur

    On the hierarchy of partially invariant submodels of differential equations

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    It is noticed, that partially invariant solution (PIS) of differential equations in many cases can be represented as an invariant reduction of some PIS of the higher rank. This introduce a hierarchic structure in the set of all PISs of a given system of differential equations. By using this structure one can significantly decrease an amount of calculations required in enumeration of all PISs for a given system of partially differential equations. An equivalence of the two-step and the direct ways of construction of PISs is proved. In this framework the complete classification of regular partially invariant solutions of ideal MHD equations is given

    Conditional linearizability criteria for a system of third-order ordinary differential equations

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    We provide linearizability criteria for a class of systems of third-order ordinary differential equations (ODEs) that is cubically semi-linear in the first derivative, by differentiating a system of second-order quadratically semi-linear ODEs and using the original system to replace the second derivative. The procedure developed splits into two cases, those where the coefficients are constant and those where they are variables. Both cases are discussed and examples given

    Nambu-Poisson dynamics with some applications

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    Short introduction in NPD with several applications to (in)finite dimensional problems of mechanics, hydrodynamics, M-theory and quanputing is given.Comment: 11 page

    Method for preserving the viability of a chicken embryo with a shell defect in experiment

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    The egg has always been and remains an ideal object for conducting various scientific research. An egg is an isolated egg cell outside the mother’s body. Therefore, it is an ideal object for studying embryogenesis and performing various manipulations during embryogenesis and before the birth of a viable organism. The existing methods allow conducting experimental manipulations with the embryo in  situ, inside the egg shells without damaging them. However, the achievement of ideal parameters for closing the defect of the fertilized egg shell in the experiment is the key to  the successful completion of the experiment. Periods of embryogenesis, especially at the last stage, when osteogenesis occurs, require the presence of a sufficient amount of calcium ions in the metabolism of the developing chicken, which are vital for the formation of a full-fledged chicken.The aim: to develop an optimal method for closing the defect and fixing the egg shell after manipulation or during the experiment.Materials and methods. The experiment was carried out on fertile eggs of the breed of chickens – meat breed of broilers Ross-308 (ROSS-308), JSC Poultry Farm “NovoBaryshevskaya” (Koltsovo, Novosibirsk Region, Russian Federation). In the experiment, 120 fertilized eggs were used. Eggs weighing 60–70 g were incubated at a temperature of 37.5–38.0 °C and 50–55 % humidity. Comparative anatomical and physiological parameters were evaluated on the 7th, 14th, 20th day of incubation and on the 1st day of the postnatal period. In the experimental group, the shell defect was covered with a fragment of the egg shell of the donor. Incubation was carried out in an incubator – a household incubator “Nesushka” (Novosibirsk, Russian Federation).Results. The proposed method of fixing and closing the defect of the fertilized egg shell excludes the use of foreign materials that have an adverse effect on the development of the embryo. There were no anatomical and physiological deviations in the chicks of the study group when comparing the indicators with the parameters in the comparison group and the Hamburger – Hamilton classification

    Тулиевый лазер при уротелиальной карциноме мочевого пузыря с распространением на устье мочеточника

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    Urothelial transitional cell cancer in developed countries is the 4th most common. In terms of frequency, it is outstripped only by prostate, breast, lung, and colorectal cancer. In the vast majority of cases, urothelial carcinoma develops in the bladder. It accounts for 90—95 % of all cases of transitional cell cancer of the urinary tract. Much less often, in 5—10 % have to deal with its localization in the upper urinary tract (in the calico-pelvic system or ureter). In 17 % of upper urinary tract cancers, bladder cancer is simultaneously diagnosed. The incidence of urothelial transitional cell cancer has increased over the past few decades as a result of improved diagnosis and improved survival of patients with this nosology. The use of modern, high-tech equipment for visualization and direct surgical intervention contributes to such results. The use of laser energy as the main tool for tissue dissection in endoscopic oncourology reveals the undeniable advantages of this method in comparison with the traditional electrosurgery.We present a clinical observation of the diagnosis and surgical treatment of urothelial bladder cancer with invasion of the ureter, performed by en-bloc tulium laser. An operation was performed-transurethral resection of a urothelial bladder tumor with invasion of the ureter, performed by en-bloc tulium laser. Intraoperatively, ureteropieloscopy was performed, and the tumor did not spread to the upper urinary tract beyond the intramural part of the ureter. Thanks to the precision of the action of the tulium laser on the tissue, not resection, but, in fact, dissection of the bladder wall, a high-quality macropreparation was obtained, which made it possible to establish a final diagnosis. Histological conclusion: from the bladder — non-invasive urothelial cancer G2-3; from the mouth of the left ureter — fragments of fibrous tissue lined with urothelium from atypia. 3 months after the operation — no recurrence of urothelial cancer was revealed, which indicates a high quality of the operation.This clinical observation demonstrates the superiority of laser en-bloc dissection compared to the treatment of bladder tumors. Obtaining a macro-product of urothelial transitional cell cancer of the highest quality can contribute to avoiding unjustified radical nephrureterectomies and conducting organ-preserving treatment, for absolute and elective indications. The 1.94 µm Tulium Erbium laser is an effective tool for performing minimally invasive transurethral interventions in non-invasive bladder cancer.Уротелиальный переходно-клеточный рак в развитых странах занимает 4-е место по распространенности. По частоте встречаемости его опережают только рак предстательной железы, молочной железы, легкого и колоректальный рак. В подавляющем большинстве случаев уротелиальная карцинома развивается в мочевом пузыре. На ее долю приходится 90—95 % всех случаев переходно-клеточного рака мочевыводящих путей. Значительно реже (5—10 %) приходиться иметь дело с его локализацией в верхних мочевыводящих путях (в чашечно-лоханочной системе или мочеточнике). В 17 % случаев при раке верхних мочевыводящих путей одновременно диагностируют рак мочевого пузыря. За последние несколько десятилетий частота встречаемости уротелиального переходно-клеточного рака возросла в результате улучшения диагностики и увеличения выживаемости пациентов с данной нозологией. Таким результатам способствует применение современного, высокотехнологичного оборудования для визуализации и непосредственного проведения оперативного вмешательства. Использование лазерной энергии в качестве основного инструмента для диссекции тканей в эндоскопической онкоурологии раскрывает неоспоримые преимущества данного метода по сравнению со ставшей уже традиционной электрохирургией.представляем клиническое наблюдение диагностики и оперативного лечения уротелиального рака мочевого пузыря с инвазией в мочеточник, проведенного en-bloc тулиевым лазером. Пациентке en-bloc тулиевым лазером выполнена трансуретральная резекция уротелиальной опухоли мочевого пузыря с инвазией в мочеточник. Интраоперационно проведена уретеропиелоскопия, выявлено отсутствие распространения опухоли в верхние мочевыводящие пути за пределы интрамурального отдела мочеточника. благодаря прецизионности воздействия тулиевого лазера на ткань, не резекции, а, по сути, диссекции стенки мочевого пузыря получен макропрепарат высокого качества, позволивший установить окончательный диагноз. Гистологическое заключение: из мочевого пузыря — неинвазивный уротелиальный рак G2-3; из устья левого мочеточника — фрагменты фиброзной ткани, выстланные уротелием из атипии. Через 3 мес после вмешательства данных о наличии рецидива уротелиального рака не выявлено, что говорит о высоком качестве проведенной операции.приведенное клиническое наблюдение демонстрирует превосходство лазерной en-bloc диссекции по сравнению с трансуретральной резекцией опухолей мочевого пузыря. Получение макропрепарата уротелиального переходно-клеточный рака наивысшего качества позволяет избегать необоснованных радикальных нефроуретерэктомий и способствует проведению органосохраняющего лечения по абсолютным и элективным показаниям. Тулий-эрбиевый лазер с длиной волны излучения 1,94 мкм — эффективный инструмент для выполнения малоинвазивных трансуретральных вмешательств при неинвазивном раке мочевого пузыря
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