203 research outputs found
Series expansions for the third incomplete elliptic integral via partial fraction decompositions
We find convergent double series expansions for Legendre's third incomplete
elliptic integral valid in overlapping subdomains of the unit square. Truncated
expansions provide asymptotic approximations in the neighbourhood of the
logarithmic singularity if one of the variables approaches this point
faster than the other. Each approximation is accompanied by an error bound. For
a curve with an arbitrary slope at our expansions can be rearranged
into asymptotic expansions depending on a point on the curve. For reader's
convenience we give some numeric examples and explicit expressions for
low-order approximations.Comment: The paper has been substantially updated (hopefully improved) and
divided in two parts. This part is about third incomplete elliptic integral.
10 page
A Multi-Scale Homogenization Technique Applied to the Elastic Properties of Solders
In modern microelectronic systems solder materials are frequently used. Consequently, it is of great importance to predict their lifetime and stability. In order to perform such an analysis, material properties are required. Since electronic devices and therefore the amounts of used materials become smaller and smaller, the influence of a changing microstructure on the mechanical properties must be examined. First, some analytical methods will be presented leading to upper and lower bounds for standard solder alloys. They also allow for an examination of the influence of certain micro-geometries. Second, a multi-scale approach is used in order to perform a more general analysis of different micro-structures. The constitutive equations are stated and a homogenization technique for elastic properties of arbitrary structures is derived. The resulting equations are solved numerically and the results are presented. For lamellar-type of structures, closed-form formulas are derived and the results will be compared to the numerical ones
MECHANISMS OF DESTRUCTION AND SYNTHESIS OF LIQUID MEDIA, USED IN THE FOOD INDUSTRY UNDER NON-EQUILIBRIUM CONDITIONS
The formation of food liquid medium structures containing at least 70 % of disperse particles with high dispersiveness has been considered. The possible formation mechanisms of food liquid medium structure when slow (hydrodynamic) and quick (acoustic) processes create favorable conditions for cavitation have been studied. The possibility to control these processes for initiation of mechanical and kinetic reactions that change the structure of the medium has been demonstrated. The invert syrup has been selected as the study object. The change in the invert syrup structure before and after such cavitation treatment has been recorded with the use of metallographic microscope Nikon Eclipse MA100. The decrease in disperse phase sizes from 2–3 µm to 0.1–0.4 µm along with establishing the high uniformity of component distribution as compared to the syrup without cavitation process treatment has been detected. The formation of food liquid medium structures containing at least 70 % of disperse particles with high dispersiveness has been considered. The possible formation mechanisms of food liquid medium structure when slow (hydrodynamic) and quick (acoustic) processes create favorable conditions for cavitation have been studied. The possibility to control these processes for initiation of mechanical and kinetic reactions that change the structure of the medium has been demonstrated. The invert syrup has been selected as the study object. The change in the invert syrup structure before and after such cavitation treatment has been recorded with the use of metallographic microscope Nikon Eclipse MA100. The decrease in disperse phase sizes from 2–3 µm to 0.1–0.4 µm along with establishing the high uniformity of component distribution as compared to the syrup without cavitation process treatment has been detected.
Death of the TonB Shuttle Hypothesis
A complex of ExbB, ExbD, and TonB couples cytoplasmic membrane (CM) proton motive force (pmf) to the active transport of large, scarce, or important nutrients across the outer membrane (OM). TonB interacts with OM transporters to enable ligand transport. Several mechanical models and a shuttle model explain how TonB might work. In the mechanical models, TonB remains attached to the CM during energy transduction, while in the shuttle model the TonB N terminus leaves the CM to deliver conformationally stored potential energy to OM transporters. Previous studies suggested that TonB did not shuttle based on the activity of a GFP–TonB fusion that was anchored in the CM by the GFP moiety. When we recreated the GFP–TonB fusion to extend those studies, in our hands it was proteolytically unstable, giving rise to potentially shuttleable degradation products. Recently, we discovered that a fusion of the Vibrio cholerae ToxR cytoplasmic domain to the N terminus of TonB was proteolytically stable. ToxR–TonB was able to be completely converted into a proteinase K-resistant conformation in response to loss of pmf in spheroplasts and exhibited an ability to form a pmf-dependent formaldehyde crosslink to ExbD, both indicators of its location in the CM. Most importantly, ToxR–TonB had the same relative specific activity as wild-type TonB. Taken together, these results provide conclusive evidence that TonB does not shuttle during energy transduction. We had previously concluded that TonB shuttles based on the use of an Oregon Green® 488 maleimide probe to assess periplasmic accessibility of N-terminal TonB. Here we show that the probe was permeant to the CM, thus permitting the labeling of the TonB N-terminus. These former results are reinterpreted in the context that TonB does not shuttle, and suggest the existence of a signal transduction pathway from OM to cytoplasm
Npo Work in the Circumstances of COVID-19
The coronavirus pandemic suddenly hit the world, as a result of which for some time all spheres of activity were in a vulnerable position, which demonstrated the countries ‘ unpreparedness for such phenomena. The adaptation to the new living conditions, organized by the heads of organizations themselves, in the form of transferring communication, work, and meetings to the online space, allowed businesses, government agencies, and the non-profit sector to return to their activities and continue to provide services to customers. In this work, the experience of non-profit organizations of the Volga Federal District was analyzed and the disadvantages and advantages of working in the pandemic were identified, according to the heads of SO NPOs.Пандемия коронавирусной инфекции неожиданно обрушилась на мир, в результате чего на некоторое время все сферы деятельности оказались в уязвимом положении, что продемонстрировало неготовность стран к подобным явлениям. Организованная собственными силами руководителей организаций адаптация под новые условия жизни в виде переноса общения, работы, встреч в онлайн-пространство позволила бизнесу, государственным структурам и некоммерческому сектору вернуться к своей деятельности и продолжить оказывать услуги клиентам. В данной работе был проанализирован опыт некоммерческих организаций Приволжского федерального округа и на основе мнений руководителей СО НКО выявлены плюсы и минусы работы в пандемию
Bookstagram as a new type of book blog
В статье анализируются особенности интернет-сервиса Instagram как основы для ведения книжного блога. Обсуждается место и значение букстаграма в ряду социальных сервисов на книжную тематику, рассматривается его специфика и перспективы развития.The article presents an analysis of the Instagram service as a base for book blog. The place and importance of “Bookstagram” among Internet communication social book services are discussed; specifics and development prospects of bookstagram as a social net with particular opportunities are considered
TECHNOLOGICAL PROPERTIES OF FLOUR AND THEIR EFFECT ON QUALITY INDICATORS OF SUGAR COOKIES
The main recipe component of most types of flour confectionery is wheat flour, the technological properties of which largely effect not only the quality indicators of the finished product, but also the stability of the technological flow of its production. However, today, in Russia there are no specialized requirements for the quality of wheat flour for confectionery, in contrast to the requirements for the baking wheat flour. The article lists the main problems and features of the quality of Russian wheat flour consisting in the absence of target classifications of grain and a decrease in its qualitative potential, in particular, a decrease in the amount of gluten and improvement of its quality. As part of the work, the influence of the technological properties of wheat flour on the rheological parameters of the dough and the quality of sugar cookies, which are traditionally in high demand of population groups of every age, was studied, while the share of domestic products is more than 85%. The work was performed in the laboratory of flour confectionery products of All-Russian Scientific Research Institute of Confectionery Industry. The determination of organoleptic, physical and chemical, structural and mechanical indicators of raw materials, semi-finished products and finished products was carried out by standard methods.The main recipe component of most types of flour confectionery is wheat flour, the technological properties of which largely effect not only the quality indicators of the finished product, but also the stability of the technological flow of its production. However, today, in Russia there are no specialized requirements for the quality of wheat flour for confectionery, in contrast to the requirements for the baking wheat flour. The article lists the main problems and features of the quality of Russian wheat flour consisting in the absence of target classifications of grain and a decrease in its qualitative potential, in particular, a decrease in the amount of gluten and improvement of its quality. As part of the work, the influence of the technological properties of wheat flour on the rheological parameters of the dough and the quality of sugar cookies, which are traditionally in high demand of population groups of every age, was studied, while the share of domestic products is more than 85%. The work was performed in the laboratory of flour confectionery products of All-Russian Scientific Research Institute of Confectionery Industry. The determination of organoleptic, physical and chemical, structural and mechanical indicators of raw materials, semi-finished products and finished products was carried out by standard methods
- …