Direct observation of superconducting vortex clusters pinned by a periodic array of magnetic dots in ferromagnetic/superconducting hybrid structures

Strong pinning of superconducting flux quanta by a square array of 1 $\mu$m-sized ferromagnetic dots in a magnetic-vortex state was visualized by low-temperature magnetic force microscopy (LT-MFM). A direct correlation of the superconducting flux lines with the positions of the dots was derived. The force that the MFM tip exerts on the individual vortex in the depinning process was used to estimate the spatial modulation of the pinning potential. It was found, that the superconducting vortices which are preferably located on top of the Py dots experience about 15 times stronger pinning forces as compared to the pinning force in the pure Nb film. The strong pinning exceeds the repulsive interaction between the superconducting vortices and allows the vortex clusters to be located at each dot. Our microscopic studies are consistent with global magnetoresistace measurements on these hybrid structures.Comment: 4 pages, 4 figure

Quantitative assessment of pinning forces and the superconducting gap in NbN thin films from complementary magnetic force microscopy and transport measurements

Epitaxial niobium-nitride thin films with a critical temperature of Tc=16K and a thickness of 100nm were fabricated on MgO(100) substrates by pulsed laser deposition. Low-temperature magnetic force microscopy (MFM) images of the supercurrent vortices were measured after field cooling in a magnetic field of 3mT at various temperatures. Temperature dependence of the penetration depth has been evaluated by a two-dimensional fitting of the vortex profiles in the monopole-monopole model. Its subsequent fit to a single s-wave gap function results in the superconducting gap amplitude Delta(0) = 2.9 meV = 2.1*kB*Tc, in perfect agreement with previous reports. The pinning force has been independently estimated from local depinning of individual vortices by lateral forces exerted by the MFM tip and from transport measurements. A good quantitative agreement between the two techniques shows that for low fields, B << Hc2, MFM is a powerful and reliable technique to probe the local variations of the pinning landscape. We also demonstrate that the monopole model can be successfully applied even for thin films with a thickness comparable to the penetration depth.Comment: 6 pages, 6 figures, 2 table

Спосіб визначення релаксаційного зусилля тушок риби

There have been repeated cases of fish sales during the spawning period in the Ukrainian market, which consumer value is much lower, and fish re-freezing products. The aforementioned methods of abuse can be identified by commodity experts, while ordinary consumers, unfortunately, often cannot independently determine the quality of the fish. The basis of the vast majority of sensory checks of the elastic properties of fish is the process of compressing the product. The advantage of determining the surface relaxation rate is that it is non-destructive testing and the product appearance of the product after the examination does not change. However, this method requires some practical experience and depends essentially on the qualifications of an expert. The method and equipment for instrumental assessment of relaxation compression deformation force to define structural and mechanical properties of fish is given; it makes possible to minimize the experimenter influence on the results and obtain a quantitative value of relaxation speed at anytime in the experiment. The method of investigation of relaxation force and the rate of fish carcasses relaxation was theoretically grounded. A 3D-diagram of force that act on the indenter while pressing the surface of white cupid carcass is given. The type of dynamometer and measuring device for fixation of relaxation force dynamics is grounded. There was developed the sensor for determining the dynamics of the relaxation force with a constant depth of lowering of the indenter; scheme and photo of it is given. The mathematical models of relaxation velocity at axial deformation of compression and tension were constructed. The proposed method for quantifying the relaxation rate involves the construction of a compression deformation curve in the second of pressing a fish carcass and determining their angle of inclination. Based on the mathematical analysis of the deformation curves, it was found that for chilled meat of white cupid for 8 hours of storage, the relaxation rate at strain by 33% is greater than for the compression deformation; the primary force upon pressing on the product is 23% greater than when the specimen is subjected to a similar cross-sectional area. The developed methodology and system allows to determine the relaxation force when squeezing a fish sample just like a commodity science expert does and make quantitative assessment of its structural and mechanical properties.На ринку України неодноразово спостерігалися випадки продажів риби нерестового періоду, споживча цінність якої є значно нижчою, та рибних продуктів повторної заморозки. Вищезгадані способи зловживань можуть бути ідентифіковані експертами-товарознавцями, тоді як пересічні споживачі нажаль, частіше не можуть самостійно визначити якість риби. В основу переважної більшості сенсорних перевірок пружних властивостей риби покладено процес стискання продукту. Перевагою визначення швидкості релаксації поверхні є те, що це неруйнівний контроль і товарний вигляд продукту після експертизи не змінюється. Проте такий спосіб вимагає певного практичного досвіду та суттєво залежить від кваліфікації експерта. Запропоновано методику та обладнання для інструментальної оцінки релаксаційного зусилля деформації стиску для визначення структурно-механічних властивостей риби, що дозволяє мінімізувати вплив експериментатора на результати та отримати кількісні значення швидкості релаксації в будь який момент часу експерименту. Теоретично обґрунтовано спосіб дослідження релаксаційного зусилля та швидкості релаксації тушок риби. Наведено тривимірну схему сил, що діють на індентор під час натискання на поверхню тушки білого амура, враховуючи зсув шарів м’язів. Обґрунтовано тип динамометра та вимірювального приладу для фіксації динаміки релаксаційного зусилля. Створено датчик для визначення динаміки релаксаційного зусилля із сталою глибиною опускання індентора, наведено його схему та фотографію.&nbsp; Встановлено відмінність між швидкістю релаксації при деформації стиску та розтягу. Побудовано математичні моделі швидкості релаксації при осьовій деформації стиску та розтягу. Запропонована методика кількісної оцінки швидкості релаксації передбачає побудову дотичних до кривої деформації стиску на другій секунді натискання на тушку риби. Та&nbsp; визначення їх кута нахилу. На підставі математичного аналізу кривих деформації, встановлено, що для охолодженого м’яса білого амура 8 годин зберігання швидкість релаксації при деформації розтягу на 33% більшою ніж при деформації стиску, початкове зусилля при надавлюванні на продукт на 23,5% більше ніж при розтягуванні зразка аналогічної площі поперечного перерізу. Розроблена методика та система дозволяє визначити релаксаційне зусилля при здавлюванні зразка риби подібно до того, як це робить товарознавець-експерт та кількісно оцінити його структурно-механічні властивості

Долговременная динамика соотношения взрослых и молодых птиц у ближних и дальних мигрантов на осеннем пролете на Куршской косе Балтийского моря

Было проанализировано соотношение взрослых и молодых птиц на осеннем пролете на Куршской косе Балтийского моря у 25 видов ближних и 19 дальних мигрантов в период с 1962 по 2016 гг. Сравнительный анализ показал, что доля взрослых особей среди пойманных в большие ловушки «рыбачинского типа» птиц была значимо выше у ближних мигрантов (19,4%), чем у дальних (5,4%). У видов, совершающих преимущественно дневные миграции, доля взрослых особей была выше, чем у ночных мигрантов (24,3% против 7,4% у ближних мигрантов и 7,4% против 4,5% – у дальних). У подавляющего большинства видов были выявлены значительные межгодовые колебания в соотношении взрослых и молодых особей. Однако значимые долговременные тренды в изменении этого соотношения были выявлены только у 3 видов ближних мигрантов и одного дальнего мигранта. Доля молодых особей, отлавливаемых на осеннем пролете, оказалась значимо связанной со средней температурой воздуха в Балтийском регионе весной и в начале лета (июнь): чем выше была температура в этот период, тем большая доля молодых птиц присутствовала в осенних отловах. Такая связь была выявлена у 8 видов ближних и 2 дальних мигрантов. Мы предполагаем, что это объясняется, в первую очередь, лучшей успешностью размножения этих видов в годы с высокой температурой воздуха весной и в начале лета в исследуемом регионе

Spatial distribution of breeding Pied Flycatchers Ficedula hypoleuca in respect to their natal sites

Study of philopatry and dispersal of pied flycatchers Ficedula hypoleuca was launched on the Courish Spit (SE Baltic) in 1981. Since then, ca. 9,000 nestlings were ringed at different sites in the Russian part of the Courish Spit. A total of 557 individuals ringed as pulli were recaptured in subsequent seasons in the study area. Both males and females are more often recaptured in the plots where they were ringed than in other plots. These results were interpreted in the framework of the hypothesis forwarded by Löhrl (1959) and supported by Berndt & Winkel (1979). These authors suggested that cavity nesters (pied flycatchers and collared flycatchers F. albicollis) imprint their future local breeding area during the period of postfledging exploration. Birds that survive until the next spring, return to these imprinted areas to breed. A similar study done by Sokolov et al. (1984) on the Courish Spit in an open nesting species, the chaffinch Fringilla coelebs, confirmed this finding. We assumed that juvenile pied flycatchers disperse for varying distances during their postfledging movements and imprint a local area, some 1–5 kilometres in diameter. This area is the goal of their migration next spring. It is suggested that in spring, yearlings are non–randomly distributed in respect to the area they have imprinted as juveniles. Recently, Vysotsky (2000, 2001) re–analysed the same data on philopatry of pied flycatchers on the Courish Spit and forwarded an alternative hypothesis. He suggests that juveniles, both males and females, do not imprint any local area during the postfledging period, but are distributed randomly across the area of several dozens of kilometres in spring. Vysotsky was able to show that distribution of distances of natal dispersal did not differ from the random pattern the study plot which was an 8.5 km long line of nest boxes along the Courish Spit. The aim of this study was to test these two alternative hypotheses. To do so, we set up nine new study plots in 2000. Over 800 nest–boxes were made available for the birds (in addition to the old 400) in the 44 km long area. We recaptured pied flycatchers returning for breeding during four years, 2000–2003. The distribution of natal dispersal distances was compared with the null model which assumes that pied flycatchers settle randomly in the study area. We took all nest boxes from which pied flycatchers successfully fledged in a particular year and all next boxes where we were able to capture either a male or a female in the subsequent year, and calculated the distances between each pair of such nest boxes. Simulations were run separately for each sex. Theoretical distributions already include control efficiency. If some nest boxes were not checked in some year, or if we failed to capture one or both members of a breeding pair, we did not include this nest box in the model. Some birds could settle outside the study plot. Therefore, the theoretical distribution may underestimate the actual range of natal dispersal, but is unlikely to overestimate it. The number of females ringed as nestlings and recaptured as one–year–old birds was 43. The distribution of their natal distances (mean 6,8 km, SE = 0,81; median 5,4 km) was not significantly different from the pattern predicted by the null model (Wilcoxon matched pairs test: z = 1,25; p = 0,21). Conversely, males settled significantly closer to their natal nest box (n = 83; mean 4,3 km, SE = 0,57; median 2,5 km) than predicted by the model (Wilcoxon matched pairs test: z = 2,45; p = 0,014). For example, 24% of males settle within one km from their natal site, as compared with 7% predicted by the model. Males are found with a greater than chance probability within the 7 km zone around their natal site. The hypothesis by Vysotsky (2000) can thus be rejected for pied flycatcher males. Pied flycatcher females are known to settle at larger distances from their natal nest box. The very fact that were controlled 83 males and only 43 females suggests, assumed that sex ratio at fledging is close to being equal and that true survival rates during the first year of life do not differ greatly between the sexes, that many females emigrated from of our study plot. This does not mean that juvenile females do not imprint a home area during the postfledging period, as suggested by Vysotsky (2000). We think that the reason for this is not the inadequate navigational ability of the females but the fact that they were attracted by a prospecting male at some distance from their migratory destination and settle there. Such intercepting was suggested by Fedorov (1996) for Acrocephalus warblers, and it may exist in other migratory passerines. This is supported by the data on natal site fidelity from Spain which show that in Spanish pied flycatcher populations, recruitment rate did not differ between female and male juveniles (Potti & Montalvo, 1991). Females from these southern populations have a limited chance to be attracted by prospecting males in even more southern areas

АНАЛІЗ ЛЕТАЛЬНОСТІ ЗА УСКЛАДНЕНОГО СИНДРОМУ ДІАБЕТИЧНОЇ СТОПИ ТА СЕПСИСУ

Обстежені в динаміці 724 пацієнта, у яких діагностований ускладнений синдром діабетичної стопи (СДС), у 71 (9,8%) з них захворювання обтяжене сепсисом. Тяжкість стану хворих при СДС залежала від тривалостігнійно-некротичного процесу на стопі, у хворих на сепсис така залежність не виявлена. Всі хворі з приводу СДС без сепсису оперовані. Померли 36 хворих, (летальність 5,5%), за наявності сепсису - 42 (летальність59,1%). Причиною сепсису у хворих за ускладненого СДС була переважно волога гангрена нижніх кінцівок. Померли 13 (30,9%) хворих на сепсис, яких не оперували, з них 5 - відмовились від оперативного втручання, померли в перші години після госпіталізації внаслідок необоротного пошкодження органів і систем

The Rotating Gliding Discharge in Quartz Tube and Open Half-Space at Atmospheric Pressure

Rotating sliding discharge (RGD) was investigated into limited volume and open half-space. The cur-rent-voltage characteristics of the discharge and its specifications are described. The results of optical research: photos and emission spectra of the discharge are presented

Методика оптимизации выбора параметров климатических камер для испытаний

Проведено дослідження швидкості нагріву та охолодження в кліматичних камерах та на їх основі розроблено методику, яка дозволяє оптимізувати вибір кліматичної камери за параметрами потрібного та достатнього корисного об’єму залежно від теплофізичних властивостей та габаритних розмірів досліджуваних об’єктів та технологічних можливостей камери.Research of speed of heating and cooling is conducted in climatic chambers and on their basis a method which allows to optimize the choice of climatic chamber after the parameters of necessary and sufficient useful volume depending on thermophysical properties and overall sizes of the probed objects and technological possibilities of chamber is developed.Проведено исследование скорости нагрева и охлаждения в климатических камерах и на их основе разработана методика, которая позволяет оптимизировать выбор климатической камеры за параметрами нужного и достаточного полезного объема в зависимости от теплофизических свойств и габаритных размеров исследуемых объектов и технологических возможностей камеры

Automation of Data Management Processes in Cloud Storage

In the modern world, with the development of informational, scientific, and technical resources, data volumes are rapidly increasing. Cloud services become critically important for supporting and optimizing the management of large amounts of data. With the advancement of technologies, there is a need to enhance methods of managing vast amounts of information. Modern requirements for efficiency and security pose a challenge to business sectors, and it is precisely here that the automation of processes in cloud services becomes key to achieving a high level of functionality and protection. In this article, we will explore the importance of process automation in cloud services, how these technologies contribute to optimizing data management, and ensure security in processing a large volume of information