Search

Робота містить узагальнення осадження частинок для покращення фізики процесу моделювання та для того, щоб зробити його більш схожим на реальні процеси осадження, такі як випаровування частинок, яке полягає у притяганні пароподібних і газоподібних частинок шляхом зменшення тиску повітря та скупчення інших молекул повітря. Це не тільки зменшує енергію, необхідну для випаровування, але також забезпечує більш прямий шлях до області осадження, оскільки частинки пари не так часто перенаправляються іншими частинками всередині камери. Хоча ми не маємо справу з бомбардуванням у нашому підході, ми пропонуємо метод генерації кластерів випадкової форми та розміру, починаючи від окремої частинки до набору частинок, щоб зробити моделювання більш репрезентативним для експериментальної реальності. Згідно з результатами, отриманими в нашому дослідженні, зростання інтерфейсу при випадковому осадженні з парової фази відбувається за двома різними режимами (перші кластери вирощуються випадковим чином шляхом створення інтерфейсу, який виріс в результаті осадження або випаровування частинок через різницю між середнім хімічним потенціалом пари Uv і потенціалом інтерфейсу Ui). Експоненти росту (β) і шорсткості (α) були стабільними зі збільшенням розміру підкладки (L) та кількості частинок (N), що бомбардуються. Ці експоненти чутливі до зміни Ui, де α зменшується, коли Ui змінюється від 0 до − 6, обернено до експоненти β. Усі поверхні, отримані в рамках цієї моделі, мають фрактальні властивості. Крім того, техніка Грінвуда та Вільямсона, яка полягає в заміні шорстко-шорсткого контакту шорстко-гладким, геометрично коректна на рівні міжвузлів і менш коректна по відношенню до теплової задачі відповідно по шорсткості інтерфейсів контактних поверхонь. In the present work, we provide a generalization of particle deposition to enhance the physics of the simulation process and make it more similar to real deposition processes, such as particle evaporation, which is tuned to attract vapor and gaseous particles by reducing air pressure and crowding of other air molecules. This not only reduces the energy required for evaporation but also allows for a more direct path to the area of deposition, as the vapor particles are not as frequently redirected by other particles within the chamber. Although we do not deal with bombardment in our approach, we provide a method to generate clusters of random shape and size, ranging from a single particle to a collection of particles, in order to make the simulation more representative of experimental reality. According to the results obtained from our study, interface growth in random vapor deposition follows two distinct regimes (the first clusters are grown randomly by building an interface which has grown as a result of deposition or evaporation of particles due to the difference between the average chemical vapor potential Uv and interface Ui). Growth (β) and roughness (α) exponents were stable with increasing substrate size (L) and a number of bombarded particles (N). These exponents are sensitive to the variation of Ui, where α decreases as Ui changes from 0 to − 6 inversely to the exponent β. All the surfaces obtained by this model have fractal properties. In addition, the technique of Greenwood and Williamson which consists in replacing the rough-rough contact by a rough-smooth contact is geometrically valid at the level of the interstices and less valid with respect to a thermal problem according to the roughness of interfaces of the surfaces in contact.

Використовуючи теорію високого порядку (HSDT), у роботі представлено дослідження термічного жолоблення функціонально градуйованих (FG) сендвіч-пластин, підданих різному підвищенню температури по всій їх товщині, що спираються на двопараметричну пружну основу. Передбачається, що механічні властивості FG сендвіч-пластин поступово змінюються з товщиною відповідно до степеневого закону (P-FGM). Проміжний шар однорідний і виготовлений з чисто керамічного матеріалу. Принцип віртуальних робіт використовується для отримання рівнянь стійкості, розв’язки яких отримують на основі методики розв’язування рівнянь Нав’є. Отримані результати порівнюються з результатами інших досліджень. Потім проводиться параметричне дослідження для вивчення впливу геометричних і механічних характеристик, таких як співвідношення розмірів (ширина, довжина і товщина), індекс матеріалу (k) та вплив пружної основи на критичну температуру жолоблення. Using a high order theory (HSDT), this work presents a study of thermal buckling of functionally graded (FG) sandwich plates subjected to various temperature rises across their thickness and resting on a twoparameter elastic foundation. The mechanical properties of the FG sandwich plates are supposed to change gradually through the thickness according to a power law (P-FGM). The intermediate layer is homogeneous and made of a purely ceramic material. The principle of virtual works is used to obtain stability equations, and their solutions are obtained based on Navier’s solution technique. The obtained results are compared with other studies in the literature. Then, a parametric study is conducted to investigate the influence of geometric and mechanical characteristics such as the ratios of dimensions (width, length, and thickness), the material index (k), and the effect of the elastic foundation on the critical buckling temperature.

Швидкий розвиток технології проектування та висока ринкова конкуренція спонукали нас розглянути сферу виробництва сталевих труб із процесом, який повністю відповідає промисловим вимогам, а саме високочастотним (HF) індукційним зварюванням, який є найпоширенішим процесом зварювання у виробництві сталевих труб. На даний момент цей процес більш відомий для виробництва труб різного діаметру на установці Tube Gaz в Тебесі (Алжир). Серед різних відомих руйнівних випробувань для контролю труб використовується тест на твердість за Віккерсом. Цей тест дозволяє визначити еволюцію твердості в поздовжньому та поперечному напрямках зварного з'єднання. Метою нашого дослідження є характеристика процесів, які керують механічною поведінкою сталевих труб (тип S235) товщиною 2,2 мм і зовнішнім діаметром 70,70 мм, зварених HF індукцією. Аналіз показує наявність дуже різноманітних мікроструктур у досліджуваному зварному з'єднанні. The rapid development of design technology and strong market competition have prompted us to look into the field of production of steel pipes with a process that perfectly meets industrial requirements, which is high frequency (HF) induction welding, which is the most common welding process to produce steel pipes. This process is currently better known for the manufacture of pipes of different diameters at the Tube Gaz unit in Tebessa (Algeria). Among the various known destructive tests, the Vickers hardness test is used to control the pipe. This test will allow us to determine the evolution of hardness in the longitudinal and transverse directions of the welded joint. The objective of our study is based on the characterization of the processes controlling the mechanical behavior of steel pipes (type S235) with a thickness of 2.2 mm and an outside diameter of 70.70 mm, welded by HF induction. The analysis shows the existence of very diverse microstructures in the studied welded joint.

BACKGROUND AND OBJECTIVE: Acne vulgaris is one of the most common skin diseases that imposes too much mental pressure and high costs on patients. The existing treatments have low efficacy and include antibiotics and anti-inflammatory drugs, which have many complications due to the chronic nature of the disease, especially at young age, including antibiotic resistance and allergic reactions. For this reason, one of the new therapeutic approaches is the use of a vaccine with the help of the bacterium or its components. The aim of this study is to produce nanoparticles carrying the recombinant CAMP – Sialidase protein as a new chimeric antigen to be used in acne vaccine. METHODS:To express the recombinant CAMP – Sialidase protein, E. coli BL21 DE3 was used as the host. Purification of protein was done through combined urea/imidazole method and using a nickel-nitroacetic acid column. The recombinant protein was confirmed using Western Blotting by Anti – Histidine Antibody. Then, the loaded nanoparticles were prepared by recombinant protein using ionic gelation technique and tripolyphosphate. Finally, the size and zeta potential of the nanoparticles were determined by the DLS device. FINDINGS: The recombinant CAMP – Sialidase protein was confirmed after expression and purification. The size and zeta potential of nanoparticles containing recombinant CAMP – Sialidase protein at a concentration of 0.6 mg / ml were determined to be 80 nm and +27 mV, respectively, using the DLS device. The loading rate of the protein in the nanoparticles was found to be 88%. CONCLUSION: The results show that the recombinant protein is expressed completely and is successfully encapsulated in the chitosan nanoparticles.

Purpose To investigate the state of dark adaptation and macular blood flow in different forms of glaucoma. Methods Eighteen eyes of 18 patients with primary open-angle glaucoma, 14 eyes of 14 patients with pseudoexfoliation glaucoma, and 10 eyes of 10 patients with childhood glaucoma (CG) were examined by means of dark adaptometry, scanning-laser retinal flowmetry, and retinal tomography. Results All glaucomatous eyes had comparable optic disc excavation (one-way ANOVA, p = 0.138). Eyes with CG had significantly lower best-corrected visual acuity than the other groups (Tukey, all p

Introduction: Normal homeostasis system has several inhibitor mechanisms in front of the amplifiers natural clotting enzyme to prevent fibrin clots in the vessels. The main inhibitors of coagulation pathway are antithrombin (AT), protein C and protein S. Patients with hereditary deficiency of coagulation inhibitors are susceptible to venous thromboembolism (VTE). One of the major clinical manifestations of VTE is deep vein thrombosis (DVT). The present study has investigated the frequency of protein C and S deficiency among DVT patients that by using of these results and results from our previous study; we determined the most important hereditary risk factors for DVT in the Kermanshah Province of Iran with the Kurdish ethnic background. Materials and methods: We studied 150 patients from the Kermanshah Province of Iran with Kurdish ethnic background. Patients with hereditary risk factors were excluded from the study. Estimation of protein C and protein S were performed using kits from STAGO, France (Diagnostica Stago). Results: After excluding patients with confounding factors, 50 patients were remained. We found 14 patients (28%) with protein C deficiency and 10 patients (20%) with protein S deficiency. Also, 2 patients (4%) had both protein C and S deficiency. Conclusion: Comparing the results of this study with our previous study on DVT patients indicates that among inherited risk factors for DVT in our population the deficiency of protein C, S and FVL mutation are the most prevalent factors. Our results show that our population has different pattern for hereditary risk factors compared with other Asian pattern for DVT patients.

Angiogenesis, the development of new blood vessels from existing vasculature, is essentialin physiological processes such as growth and development, wound healing andreproduction. It is also involved in pathological conditions such as tumor growth, metastases,and certain chronic diseases. Angiogenesis is dependent on a delicate equilibriumbetween endogenous angiogenic and antiangiogenic factors. However, under pathologicalconditions, this tight regulation becomes lost which can result in the formation of thedifferent diseases, including corneal neovascularization, endometriosis, obesity, atherosclerosis,diabetic retinopathy, psoriasis and cancer. In general, the process of angiogenesisis a multi-factorial and highly structured sequence of cellular events comprising migration,proliferation and differentiation of endothelial cells and finally vascular formation,maturation and remodelling. Due to the critical role of angiogenesis in physiological andpathological conditions, scientists have designed various experimental models to assayangiogenesis in vitro, ex vivo and in vivo. Currently, these experimental models are usedby many researchers for several applications such as discovering angiogenic and antiangiogenicagents, and thereby for future therapeutic applications.

PurposeTo detect and quantify eye blinks during 24-hour intraocular pressure (IOP) monitoring with a contact lens sensor (CLS).MethodsA total of 249 recordings of 24-hour IOP patterns from 202 participants using a CLS were included. Software was developed to automatically detect eye blinks, and wake and sleep periods. The blink detection method was based on detection of CLS signal peaks greater than a threshold proportional to the signal amplitude. Three methods for automated detection of the sleep and wake periods were evaluated. These relied on blink detection and subsequent comparison of the local signal amplitude with a threshold proportional to the mean signal amplitude. These methods were compared to manual sleep/wake verification. In a pilot, simultaneous video recording of 10 subjects was performed to compare the software to observer-measured blink rates.ResultsMean (SD) age of participants was 57.4 ± 16.5 years (males, 49.5%). There was excellent agreement between software-detected number of blinks and visually measured blinks for both observers (intraclass correlation coefficient [ICC], 0.97 for observer 1; ICC, 0.98 for observer 2). The CLS measured a mean blink frequency of 29.8 ± 15.4 blinks/min, a blink duration of 0.26 ± 0.21 seconds and an interblink interval of 1.91 ± 2.03 seconds. The best method for identifying sleep periods had an accuracy of 95.2 ± 0.5%.ConclusionsAutomated analysis of CLS 24-hour IOP recordings can accurately quantify eye blinks, and identify sleep and wake periods.Translational relevanceThis study sheds new light on the potential importance of eye blinks in glaucoma and may contribute to improved understanding of circadian IOP characteristics.

Pathophysiology of spinal cord injury has classically bad prognosis in primary and secondary processes. This process causes inflammation, deformity and cell loss. It has been shown that Melissa officinalis is a useful herbal plant in the prevention of various neurological diseases. The present study evaluated the effects of three doses of Melissa officinalis on spinal cord injury. Thirty five adult male wistar rats were used in this study. The weight-drop contusion method was employed to induce spinal cord injury in rats. Three doses of Melissa officinalis (50, 100 and 150 mg/kg) were intraperitoneally injected once a day for 14 days in all treatment groups and all injections started one day after injury. After neurological and electrophysiological evaluations, rats were sacrificed for histological and immunohistochemistry assessments. Our results showed motor function was improved in groups received 100 and 150 mg/kg of Melissa officinalis and sensory recovery was better in 150 mg/kg of Melissa officinalis treated group compared to spinal cord injury group (p

International audience; The present work aims to look into the contribution of the extended nite element method for large deformation of cracked bodies in plane strain approximation. The unavailability of sucient mathematical tools and proofs for such problem makes the study exploratory. First, the asymptotic solution is presented. Then, a numerical analysis is realized to verify the pertinence of solution given by the asymptotic procedure, since it serves as an Xfem enrichment basis. nally, a convergence study is carried out to show the contribution of the exploitation of such method.