To determ arise the pressure in instable movement of liquid in pipe

За результатами теоретичних і експериментальних досліджень було встановлено, що тиск, який виникає при неусталеному русі рідини суттєво залежить від внутрішньої структури потоку. Від критеріїв цієї структури залежать втрати енергії на тертя, а також стійкість ламінарного режиму течії. Отримані результати досліджень дозволяють визначати ці величини і врахувати їх вплив на процес розвитку неусталеної течії рідини.At planning of the water systems it is necessary to foresee facilities of their protecting from the increase of pressure. His unexpected increase is determined a calculation and going out from the value of working pressure an air of defence which provides safe exploitation of pipes is assumed. The purpose of the offered work are experimental and theoretical researches of increase of pressure at an unwithstand motion of liquid in pipes. It is set that pressure which arises up at non-stationary motion of liquid substantially depends on the underlying structure of stream. Here take such criteria, as distributing of speeds in the living cut of stream, mode of flow et al. On them the losses of energy depend on a friction, and also firmness of the mode of laminar of flow. Dependence is got between speed of passing of transient and increase of pressure in pipes. The results of researches allow to determine the criteria of underlying structure of stream and take into account their influence on the process of development of an unwithstand flow of liquid.В результате теоретических и экспериментальных исследований было установлено, что возникающее повышение давление во время неустановившегося движения жидкости во многом зависит от внутренней структуры потока. От критериев этой структуры зависят потери энергии на трение, а также устойчивость ламинарного режима течения. Получение результаты исследования позволяют определять эти величины и учитывать их влияние на процесс развития неустановившегося движения

Vacuum-assisted therapy for patients with diabetes mellitus and chronic foot ulcers

ДИАБЕТ САХАРНЫЙСАХАРНАЯ БОЛЕЗНЬДИАБЕТИЧЕСКИЕ ОСЛОЖНЕНИЯДИАБЕТА ОСЛОЖНЕНИЯХРОНИЧЕСКИЕ РАНЫ СТОПЫ /МИКРОБ /ТЕРДИАБЕТИЧЕСКАЯ СТОПА /МИКРОБ /ТЕРЯЗВА СТОПЫ ДИАБЕТИЧЕСКАЯ /МИКРОБ /ТЕРВАКУУМ-АССИСТИРОВАННАЯ ТЕРАПИЯБАКТЕРИАЛЬНАЯ НАГРУЗКАБАКТЕРИИЦель. Определить бактериальную нагрузку ран при использовании вакуум-ассистированной терапии у пациентов с сахарным диабетом и хроническими ранами стопы. Материал и методы. Объектом исследования были пациенты с сахарным диабетом, у которых имелись хронические поверхностные (кожа, подкожная клетчатка) раны стопы с проявлениями легкой инфекции согласно классификации для определения наличия и тяжести инфекции IWGDF/IDSA. Критериями исключения были следующие: онкопатология, тяжелая сопутствующая патология, поражения костно-суставного аппарата. Пациенты лечились амбулаторно и не получали системную антибиотикотерапию. Проводилась терапия ран отрицательным давлением – 125 mm Hg в постоянном режиме. Первый этап работы выполнялся для определения уровня бактериальной нагрузки ран до и после 3 суток вакуум-ассистированной терапии (группа из 10 пациентов). Вторая группа (10 пациентов) была отобрана для определения динамики изменений бактериальной нагрузки ран после каждых 24 часов вакуум-ассистированной терапии, наблюдение проводилось на протяжении 96 часов экспозиции повязки. Уровень бактериальной нагрузки контролировали по изменениям показателя колониеобразующих единиц в грамме ткани (КОЕ/г) биопсийного материала из ран. Результаты. Средняя бактериальная нагрузка ран у пациентов первой группы после 3 суток терапии составляла 8,11±1,27 lg КОЕ/г, что на 31,9% превышало исходный уровень (р<0,05). При исследовании материала из ран пациентов второй группы установлено увеличение средней бактериальной нагрузки ран через 24, 48, 72 и 96 часов после начала терапии, на 10,8%, 16,4%, 38,9% и 58,6% соответственно (р<0,05). Заключение. Использование вакуум-ассистированной терапии у пациентов с сахарным диабетом и хроническими ранами стопы с проявлениями инфекции не обеспечивает необходимого контроля уровня бактериальной нагрузки, поэтому метод необходимо применять в комплексе с системной антибиотикотерапией.истированной терапии у пациентов с сахарным диабетом и хроническими ранами стопы.Objective. To determine the bacterial load of wounds at the application of vacuum-assisted therapy for patients with diabetes mellitus and chronic foot ulcers. Methods. The object of the research was patients with diabetes mellitus with chronic superficial (skin, subcutaneous tissues) wounds of the foot with the signs of mild infection according to the classification for determination of presence and severity of infection of IWGDF/IDSA. Oncopathology, heavy concomitant pathology and lesions of the osteoarticular apparatus were the criteria of exception. Patients were treated as out-patients and did not get system antibiotic therapy. Therapy of wounds was conducted by negative pressure – 125 mm Hg in the continuous mode. The first stage of work was conducted to find out the level of the bacterial load of wounds before and 3 days after the vacuum-assisted therapy (the group was of 10 patients). The second group (10 patients) was selected to determine the dynamics of changes of the wound bioburden level after every 24 hours of vacuum-assisted therapy, the observation was performed during 96 hours of the bandage exposure. The level of the bacterial load was controlled according to the changes of index of colony-forming units in the gram of tissue (CFU/g) of the wound biopsy material. Results. The average bioburden level of wounds for the 1st group patients after the removal of bandage was 8.11±1.27 lg CFU/g, this exceeds the initial level by 31.9 % (р<0.05). The investigation of the material from the wounds of the 2nd group patients established a considerable increase of the average bioburden level of wounds in 24, 48, 72 and 96 hours after the beginning of the therapy, 10.8 %, 16.4 %, 38.9 % and 58.6 % accordingly (р<0.05). Conclusions. In patients with diabetes mellitus and chronic wounds of the foot with signs of infection, vacuum-assisted therapy does not provide essential control of the bioburden level and should be used in combination with systemic antibiotic therapy

Observations of H3+ in the Diffuse Interstellar Medium

Surprisingly large column densities of H3+ have been detected using infrared absorption spectroscopy in seven diffuse cloud sightlines (Cygnus OB2 12, Cygnus OB2 5, HD 183143, HD 20041, WR 104, WR 118, and WR 121), demonstrating that H3+ is ubiquitous in the diffuse interstellar medium. Using the standard model of diffuse cloud chemistry, our H3+ column densities imply unreasonably long path lengths (~1 kpc) and low densities (~3 cm^-3). Complimentary millimeter-wave, infrared, and visible observations of related species suggest that the chemical model is incorrect and that the number density of H3+ must be increased by one to two orders of magnitude. Possible solutions include a reduced electron fraction, an enhanced rate of H2 ionization, and/or a smaller value of the H3+ dissociative recombination rate constant than implied by laboratory experiments.Comment: To be published in Astrophysical Journal, March 200

Enhanced cosmic-ray flux toward zeta Persei inferred from laboratory study of H3+ - e- recombination rate

The H3+ molecular ion plays a fundamental role in interstellar chemistry, as it initiates a network of chemical reactions that produce many interstellar molecules. In dense clouds, the H3+ abundance is understood using a simple chemical model, from which observations of H3+ yield valuable estimates of cloud path length, density, and temperature. On the other hand, observations of diffuse clouds have suggested that H3+ is considerably more abundant than expected from the chemical models. However, diffuse cloud models have been hampered by the uncertain values of three key parameters: the rate of H3+ destruction by electrons, the electron fraction, and the cosmic-ray ionisation rate. Here we report a direct experimental measurement of the H3+ destruction rate under nearly interstellar conditions. We also report the observation of H3+ in a diffuse cloud (towards zeta Persei) where the electron fraction is already known. Taken together, these results allow us to derive the value of the third uncertain model parameter: we find that the cosmic-ray ionisation rate in this sightline is forty times faster than previously assumed. If such a high cosmic-ray flux is indeed ubiquitous in diffuse clouds, the discrepancy between chemical models and the previous observations of H3+ can be resolved.Comment: 6 pages, Nature, in pres

Networks uncover hidden lexical borrowing in Indo-European language evolution

Language evolution is traditionally described in terms of family trees with ancestral languages splitting into descendent languages. However, it has long been recognized that language evolution also entails horizontal components, most commonly through lexical borrowing. For example, the English language was heavily influenced by Old Norse and Old French; eight per cent of its basic vocabulary is borrowed. Borrowing is a distinctly non-tree-like process—akin to horizontal gene transfer in genome evolution—that cannot be recovered by phylogenetic trees. Here, we infer the frequency of hidden borrowing among 2346 cognates (etymologically related words) of basic vocabulary distributed across 84 Indo-European languages. The dataset includes 124 (5%) known borrowings. Applying the uniformitarian principle to inventory dynamics in past and present basic vocabularies, we find that 1373 (61%) of the cognates have been affected by borrowing during their history. Our approach correctly identified 117 (94%) known borrowings. Reconstructed phylogenetic networks that capture both vertical and horizontal components of evolutionary history reveal that, on average, eight per cent of the words of basic vocabulary in each Indo-European language were involved in borrowing during evolution. Basic vocabulary is often assumed to be relatively resistant to borrowing. Our results indicate that the impact of borrowing is far more widespread than previously thought

Underwater Leidenfrost nanochemistry for creation of size-tailored zinc peroxide cancer nanotherapeutics

The dynamic underwater chemistry seen in nature is inspiring for the next generation of eco-friendly nanochemistry. In this context, green synthesis of size-tailored nanoparticles in a facile and scalable manner via a dynamic process is an interesting challenge. Simulating the volcano-induced dynamic chemistry of the deep ocean, here we demonstrate the Leidenfrost dynamic chemistry occurring in an underwater overheated confined zone as a new tool for customized creation of nanoclusters of zinc peroxide. The hydrodynamic nature of the phenomenon ensures eruption of the nanoclusters towards a much colder region, giving rise to growth of monodisperse, size-tailored nanoclusters. Such nanoparticles are investigated in terms of their cytotoxicity on suspension and adherent cells to prove their applicability as cancer nanotherapeutics. Our research can pave the way for employment of the dynamic green nanochemistry in facile, scalable fabrication of size-tailored nanoparticles for biomedical applications.Peer reviewe

New polymorph of InVO4: A high-pressure structure with six-coordinated vanadium

This document is the unedited Author’s version of a Submitted Work that was subsequently accepted for publication in Inorganic Chemestry, copyright © American Chemical Society after peer review. To access the final edited and published work see http://pubs.acs.org/doi/abs/10.1021/ic402043xA new wolframite-type polymorph of InVO4 is identified under compression near 7 GPa by in situ high-pressure (HP) X-ray diffraction (XRD) and Raman spectroscopic investigations on the stable orthorhombic InVO4. The structural transition is accompanied by a large volume collapse (Delta V/V = -14%) and a drastic increase in bulk modulus (from 69 to 168 GPa). Both techniques also show the existence of a third phase coexisting with the low- and high-pressure phases in a limited pressure range close to the transition pressure. XRD studies revealed a highly anisotropic compression in orthorhombic InVO4. In addition, the compressibility becomes nonlinear in the HP polymorph. The volume collapse in the lattice is related to an increase of the polyhedral coordination around the vanadium atoms. The transformation is not fully reversible. The drastic change in the polyhedral arrangement observed at the transition is indicative of a reconstructive phase transformation. The HP phase here found is the only modification of InVO4 reported to date with 6-fold coordinated vanadium atoms. Finally, Raman frequencies and pressure coefficients in the low- and high-pressure phases of InVO4 are reported.This research supported by the Spanish government MINECO under Grant Nos. MAT2010-21270-C04-01/04 and CSD2007-00045. O.G. acknowledges support from Vicerrectorado de Investigacion y Desarrollo of UPV (Grant No. UPV2011-0914 PAID-05-11 and UPV2011-0966 PAID-06-11). S.N.A. acknowledges support provided by Universitat de Valencia during his visit to it. B.G.-D. acknowledges the financial support from MINECO through the FPI program.Errandonea, D.; Gomis Hilario, O.; García-Domene, B.; Pellicer Porres, J.; Katari, V.; Achary, SN.; Tyagi, AK.... (2013). New polymorph of InVO4: A high-pressure structure with six-coordinated vanadium. Inorganic Chemistry. 52(21):12790-12798. https://doi.org/10.1021/ic402043xS1279012798522

Breast MRI: guidelines from the European Society of Breast Imaging

The aim of breast MRI is to obtain a reliable evaluation of any lesion within the breast. It is currently always used as an adjunct to the standard diagnostic procedures of the breast, i.e., clinical examination, mammography and ultrasound. Whereas the sensitivity of breast MRI is usually very high, specificity—as in all breast imaging modalities—depends on many factors such as reader expertise, use of adequate techniques and composition of the patient cohorts. Since breast MRI will always yield MR-only visible questionable lesions that require an MR-guided intervention for clarification, MRI should only be offered by institutions that can also offer a MRI-guided breast biopsy or that are in close contact with a site that can perform this type of biopsy for them. Radiologists involved in breast imaging should ensure that they have a thorough knowledge of the MRI techniques that are necessary for breast imaging, that they know how to evaluate a breast MRI using the ACR BI-RADS MRI lexicon, and most important, when to perform breast MRI. This manuscript provides guidelines on the current best practice for the use of breast MRI, and the methods to be used, from the European Society of Breast Imaging (EUSOBI)