Advance in the theory of ceramics/liquid metal systems wettability. Peculiarity of contact processes for transition and non—transition metals

The review and some general comments devoted to scientific problems of high temperature wetting and adhesion in systems liquid metals—solid ceramic materials were done including the analysis of data received in a last time. The theoretical treatment of high temperature wetting processes and mechanism based on traditional thermodynamic notions and new approach on atomic and atomic-electron level were developed. As ceramics various substrates namely substrates with predominated ionic interatomic bonds (oxides for example) which usually hardly wetted by liquid metals are considered first of all. The contribution of nonequilibrium and equilibrium parts of adhesion to wetting process are considered and analysed. The ”active“ metals viz metals with high enough chemical affinity for solid phase atoms or iones were divided on transition metals (d-electron orbitals are partly occupied by electrons) and nontransition metals (dorbitals are empty or completely full by electrons).Зроблено огляд та подані деякі загальні коментарі, що стосуються наукових проблем високотемпературного змочування та адгезії у системах рідкі метали—тверді керамічні матеріали, включаючи аналіз одержаних останнім часом даних. Розроблені теоретична трактовка процесів високотемпературного змочування та механізм, що базується на традиційних термодинамічних уявленнях, і також новий підхід на атомному та атомно-електронному рівні. У першу чергу як кераміка розглянуті різні субстрати, а саме, субстрати, де переважають іонні міжатомні зв’язки (наприклад, оксиди), котрі звичайно погано змочуються рідкими металами. Розглянуто й проаналізовано внесок у процес змочування нерівноважної та рівноважної складових адгезії. “Активні” метали, а саме, метали з досить високою хімічною спорідненістю до атомів твердої фази або іонів розділені на перехідні метали (d-електронні орбіталі частково заповнені електронами) та неперехідні метали (d-орбіталі не заповнені або цілком заповнені електронами).Сделан обзор и представлены некоторые общие комментарии, касающиеся научных проблем высокотемпературной смачиваемости и адгезии в системах жидкие металлы-твердые керамические материалы, включая анализ полученных в последнее время данных. Разработаны теоретическая трактовка процессов высокотемпературной смачиваемости и механизм, основанный на традиционных термодинамических представлениях, и новый подход на атомном и атомно-электронном уровне. В первую очередь в качестве керамики рассмотрены различные субстраты, а именно, субстраты с преобладающими ионными межатомными связями ISSN 0136-1732. Адгезия расплавов и пайка материалов, 2013. Спецвып. 46 53 (например, оксиды), которые обычно плохо смачиваются жидкими металлами. Рассмотрен и проанализирован вклад в процесс смачивания неравновесной и равновесной составляющих адгезии. “Активные” металлы, а именно, металлы с достаточно высоким химическим сродством к атомам твердой фазы или ионам разделены на переходные металлы (d-электронные орбитали частично заполнены электронами) и непереходные металлы (d-орбитали не заполнены или полностью заполнены электронами)

Wetting and energetics in nanoparticle etching of graphene

Molten metallic nanoparticles have recently been used to construct graphene nanostructures with crystallographic edges. The mechanism by which this happens, however, remains unclear. Here, we present a simple model that explains how a droplet can etch graphene. Two factors possibly contribute to this process: a difference between the equilibrium wettability of graphene and the substrate that supports it, or the large surface energy associated with the graphene edge. We calculate the etching velocities due to either of these factors and make testable predictions for evaluating the significance of each in graphene etching. This model is general and can be applied to other materials systems as well. As an example, we show how our model can be used to extend a current theory of droplet motion on binary semiconductor surfaces

Búsqueda de blancos terapéuticos para hidatidosis secundaria

El objetivo de nuestro trabajo es la caracterización bioquímica y ensayo como blanco terapéutico in vitro por respuesta frente a inhibidores de esta cisteín proteasa de E. granulosus, expresada en forma recombinante. Además buscamos establecer su localización en la interfase hospedador-parásito en un sistema in vitro.Asociación Parasitológica Argentin

A simulation of the NiO/Ag interface with point defects

The NiO/Ag interface has been modelled using established simulation techniques, which have been modified to include the image interactions between the oxide ions and the induced charge in the metal. The energies of point defects near the interface were calculated and it was found that the surface rumpling was such that defects with a negative net charge were favoured. This will result in a space charge layer with excess cation vacancies which will cancel the interfacial potential. A low energy interface was modelled in which the cation sub-lattice of the second oxide plane was saturated with vacancies and Ni3+. ions. Such a structure may be responsible for the observed excess of oxygen near the NiO/Ni interface, and also for the low wetting angles of metals on NiO, compared with MgO

Superficial Endobronchial Lung Cancer: Radiologic-Pathologic Correlation

Objective: To analyze the plain chest radiographic and CT findings of superficial endobronchial lung cancer and to correlate these with the findings of histopathology. Materials and Methods: This study involved 19 consecutive patients with pathologically proven lung cancer confined to the bronchial wall. Chest radiographs and CT scans were reviewed for the presence of parenchymal abnormalities, endobronchial nodules, bronchial obstruction, and bronchial wall thickening and stenosis. The CT and histopathologic findings were compared. Results: Sixteen of the 19 patients had abnormal chest radiographic findings, while in 15 (79%), CT revealed bronchial abnormalities: an endobronchial nodule in seven, bronchial obstruction in five, and bronchial wall thickening and stenosis in three. Histopathologically, the lesions appeared as endobronchial nodules in 11 patients, irregular thickening of the bronchial wall in six, elevated mucosa in one, and carcinoma in situ in one. Conclusion: CT helps detect superficial endobronchial lung cancer in 79 % of these patients, though there is some disagreement between the CT findings and the pathologic pattern of bronchial lesions. Although nonspecific, findings of bronchial obstruction or bronchial wall thickening and stenosis should not be overlooked, and if clinically necessary, bronchoscopy should be performed. Index terms: Lung, radiograph

Active contour approach for accurate quantitative airway analysis

Chronic airway disease causes structural changes in the lungs including peribronchial thickening and airway dilatation. Multi-detector computed tomography (CT) yields detailed near-isotropic images of the lungs, and thus the potential to obtain quantitative measurements of lumen diameter and airway wall thickness. Such measurements would allow standardized assessment, and physicians to diagnose and locate airway abnormalities, adapt treatment, and monitor progress over time. However, due to the sheer number of airways per patient, systematic analysis is infeasible in routine clinical practice without automation. We have developed an automated and real-time method based on active contours to estimate both airway lumen and wall dimensions; the method does not require manual contour initialization but only a starting point on the targeted airway. While the lumen contour segmentation is purely region-based, the estimation of the outer diameter considers the inner wall segmentation as well as local intensity variation, in order anticipate the presence of nearby arteries and exclude them. These properties make the method more robust than the Full-Width Half Maximum (FWHM) approach. Results are demonstrated on a phantom dataset with known dimensions and on a human dataset where the automated measurements are compared against two human operators. The average error on the phantom measurements was 0.10mm and 0.14mm for inner and outer diameters, showing sub-voxel accuracy. Similarly, the mean variation from the average manual measurement was 0.14mm and 0.18mm for inner and outer diameters respectively

Структурная неоднородность левого желудочка и ремоделирование миокарда

Aimed at studying interrelation between left ventricular (LV) structural heterogeneity and myocardial remodeling, we exa- mined a group pf subjects having coronary artery disease (CAD) of several severity degree. Based on three-dimensional reconstruc-tion of LV and using original analysis methods of esophageal ultrasound investigation data, standard parameters of myocardial re-modeling ( mean values of wall thickness and short axis LV radius, interrelations of long and short semi-axes, camera volume, myo-cardial mass and its relation to the wall thickness) were scored. The assessment of heterogeneity in LV regions was performed with space resolution 4x4 mm using parameters which are characteristic of heterogeneity of the wall thickness and curvature degree and also, scale of constitution of connective material by connective tissue. Correlation analysis performed between data of LV remodel-ing and its structural heterogeneity revealed strong correlation events studied in the heart. It proved that the higher myocardial re-modeling degree the lower heterogeneity of LV. It means that myocardial remodeling process in the setting of advancing CAD de-velops to decreased scale of LV structural heterogeneity. It is suggested that heterogeneity in normal heart serves as structural basis for myocardial remodeling.С целью изучения взаимосвязи между структурной неоднородностью левого желудочка (ЛЖ) и ремоделированием миокарда была обследована группа лиц с ишемической болезнью сердца (ИБС) различной степени тяжести. На основе трехмерной реконструкции ЛЖ с использованием оригинальных методов обработки и анализа данных чреспищеводного ультразвукового обследования пациентов были вычислены стандартные параметры ремоделирования миокарда (средние значения толщины стенки и радиуса по короткой оси ЛЖ, соотношение длинной и короткой полуосей, объем камеры, масса миокарда и ее соотношение с толщиной стенки). Оценка неоднородности структуры в регионах ЛЖ была проведена с пространственным разрешением 4 × 4 мм с использованием параметров, характеризующих степень неодинаковости толщины и кривизны сердечной стенки, а также масштаб замещения сократительного материала соединительной тканью. Корреляционный анализ между показателями ремоделирования миокарда и структурной неоднородности ЛЖ выявил наличие тесной связи между исследуемыми явлениями в сердце. Оказалось, что чем выше степень ремоделирования миокарда, тем ниже неоднородность ЛЖ. Это означает, что процесс ремоделирования миокарда на фоне прогрессирующего течения ИБС развивается в направлении снижения масштаба структурной неоднородности ЛЖ. Сформулирована гипотеза, что в нормальном сердце неоднородность создает структурный базис для ремоделирования миокарда

Persistent left superior vena cava mistaken for nodal metastasis: a case report

<p>Abstract</p> <p>Introduction</p> <p>Evaluation of the mediastinum is crucial for patients with lung cancer. Mediastinal lymph node metastases play a dramatic role in the process of staging. Physicians should be aware of the potential pitfalls regarding mediastinal evaluation. This case report provides an example.</p> <p>Case presentation</p> <p>We report the case of a 57-year-old Caucasian man who presented with a four-month history of non-productive cough. He was diagnosed with non-small cell lung cancer. Initially, it was thought to be inoperable due to the presence of a para-aortic lymph node. A more careful examination of the mediastinum revealed that the "lymph node" was in fact a persistent left superior vena cava.</p> <p>Conclusions</p> <p>This study highlights the difficulties in mediastinal staging, especially when intravenous contrast is not used. The recognition of this vascular malformation dramatically changed the therapeutic decisions, giving our patient the opportunity of surgical resection. To the best of our knowledge, such correlation has not been described in English literature.</p