Спекание таблеток диоксида урана в высокотемпературных печах

Бакалаврская работа посвящена изучению современных подходов к производству топливных таблеток для снаряжения тепловыделяющих элементов и сборок. Основное внимание обращено процессам спекания спрессованных из порошка диоксида урана топливных таблеток в высокотемпературных печах, проходящих в атмосфере водорода. В процессе выполнения работы изучена программа - «Инженерная модель спекания в печах BTU», разработанная в НИИ прикладной математики и механики Томского государственного университета. Программа предназначена для получения прогноза по спеканию топливных таблеток диоксида урана по входным данным, полученным после прессования. После ознакомления с программой проведены расчеты. Целью данной работы является освоение современных подходов к спеканию топливных таблеток из порошка диоксидаBachelor's work is devoted to the study of contemporary approaches to the production of fuel pellets Equipment for the fuel rods and assemblies. Emphasis sintering processes drawn from the compacted powder of uranium dioxide fuel pellets in high temperature furnaces, passing under a hydrogen atmosphere. In carrying out the work program studied - "Engineering model sintering furnaces BTU», developed at the Institute of Applied Mathematics and Mechanics of Tomsk State University. The program is designed to provide forecast sintered uranium dioxide fuel pellets from the input data obtained after compression. After getting acquainted with the program were calculated. The aim of this work is the development of modern approaches to the sintering of fuel pellets of uranium dioxide ceramic powde

Технологические способы вакуумно-плазменной обработки изделий для увеличения адгезии износостойких покрытий

В работе представлены экспериментальные результаты исследования комплексных технологических процессов получения износостойких нитридных покрытий, сочетающих вакуумно-дуговое напыление пленочных материалов данного типа с предварительной электронно-лучевой термической обработкой поверхности металлокерамических подложек. В работе дан анализ явлениям, происходящим как в области плазмы, так и процессам изменения функциональных характеристик исследуемых материалов. Представлены данные по измерениям микротвердости, износостойкости, а также приведены сопоставления по структуре и морфологии. Сравнивали физико-механические свойства двух видов покрытий, TiCuN и TiN, нанесённых на поверхность режущих пластин сплава ВК8. Исследования проводили с целью выявления механизмов усиления адгезии покрытий.The paper presents experimental results of investigation of complex technological processes for the production of wear-resistant nitride coatings that combine vacuum-arc deposition of film materials of this type with preliminary electron-beam thermal treatment of the surface of cermet substrates. The paper analyzes the phenomena occurring both in the plasma region and in the processes of changing the functional characteristics of the materials under study. The data on micro hardness and wear resistance measurements are presenting, and comparisons of structure and morphology are given. Physic mechanical properties of two types of coatings, TiCuN and TiN, applied to the surface of cutting inserts of VK8 alloy were comparing. Studies were carring out to identify mechanisms for enhancing adhe

Sialylation inhibition can partially revert acquired resistance to enzalutamide in prostate cancer cells

Prostate cancer is the most common cancer in men and a major cause of cancer-related deaths around the world. Prostate cancer that has spread to other parts of the body (advanced prostate cancer) is often treated with a drug called enzalutamide, which is a type of hormone therapy. Enzalutamide works by blocking the effect of the testosterone hormone on prostate cancer cells to stop them from growing. While this can be effective for several years, unfortunately, many patients being treated with enzalutamide eventually go on to become resistant to treatment, and the therapy stops working. Here, we show that prostate cancer cells that have become resistant to enzalutamide have increased levels of a type of sugar (known as sialic acid) on their surfaces. We set out to test whether stripping sialic acid from the surface of prostate cancer cells could help keep enzalutamide working for longer. Excitingly, our experiments show that treating prostate cancer cells with a drug to block sialic acid can partially reverse enzalutamide resistance. These findings suggest that drugs targeting sialic acid could be used in combination with enzalutamide therapy to disarm drug resistance and provide urgently needed new treatment options for men with prostate cancer

Capecitabine in combination with docetaxel and mitomycin C in patients with pre-treated tumours: results of an extended phase-I trial

Preclinical data suggest that the anti-tumour activity of capecitabine is enhanced by taxanes and mitomycin C through up-regulation of thymidine phosphorylase (TP). Here, we studied safety and efficacy of the combination of capecitabine with docetaxel and mitomycin C. Two dose levels (DL) were investigated: capecitabine 1000 mg m−2 b.i.d. on days 1–14, docetaxel 40 mg m−2 i.v. day 1, mitomycin C 4 or 6 mg m−2 i.v. day 1 (DL I or II). Cycles were repeated every 3 weeks. The primary aim was to determine the dose-limiting toxicities (DLT) during the first two treatment cycles and the maximum tolerated dose (MTD). A total of 46 patients (pts) refractory to standard therapies were enrolled, of whom the majority had gastrointestinal tumours (n=40). 14 pts had received ⩾3 lines of prior chemotherapy. At DL I, one out of six pts experienced DLT. At DL II, two out of six pts had DLT (mucositis grade 3). Thus, DL I was determined as MTD. Among a total of 37 pts treated on DL I the following toxicities were observed during cycles 1 and 2 (number of patients with grade 1/2/3/4 toxicity; NCI-CTC v. 3.0): anaemia 10/8/3/0, leucocytopenia 4/11/1/2, thrombocytopenia 0/1/2/0, diarrhoea 8/1/2/0, stomatitis/mucositis 3/3/1/0, nausea/vomiting 10/2/0/0, and hand-foot skin reaction 5/1/1/0. Of 30 pts who received at least two treatment cycles nine achieved complete or partial remissions, six pts achieved minor remissions, and seven pts had stable disease (tumour control rate 73%). Of note, four out of 10 patients with pancreatic cancer had partial remissions. In conclusion, capecitabine can safely be combined with docetaxel (40 mg m−2) and mitomycin C (4 mg m−2). The established regimen was well tolerated and the preliminary efficacy data in this heavily pre-treated patients population appears to be promising

Heart and systemic effects of statin pretreatment in a rat model of abdominal sepsis. Assessment by Tc99m-sestamibi biodistribition

PURPOSE: To evaluate the heart and the Tc-99m-sestamibi biodistribution after statin pretreatment in a rat model of abdominal sepsis. METHODS: Twenty-four Wistar rats were randomly distributed into four groups (n=6 per group): 1) sepsis with simvastatin treatment, 2) sepsis with vehicle, 3) sham control with simvastatin and 4) sham control with vehicle. 24 hours after cecal ligation and puncture rats received 1.0MBq of Tc-99m-sestamibi i.v. 30min after, animals were euthanized for ex-vivo tissue counting and myocardium histological analysis. RESULTS: Myocardial histologic alterations were not detected 24 hours post-sepsis. There was significantly increased cardiac Tc-99m-sestamibi activity in the sepsis group with simvastatin treatment (1.9$\pm$0.3%ID/g, p<0.001) in comparison to the sepsis group+vehicle (1.0$\pm$0.2% ID/g), control sham group+ simvastatin (1.2$\pm$0.3% ID/g) and control sham group (1.3$\pm$0.2% ID/g). Significant Tc-99m-sestamibi activity in liver, kidney and lungs was also detected in the sepsis group treated with simvastatinin comparison to the other groups. CONCLUSIONS: Statin treatment altered the biodistribution of Tc-99m-sestamibi with increased cardiac and solid organ activity in rats with abdominal sepsis, while no impact on controls. Increased myocardial tracer activity may be a result of a possible protection effect due to increased tissue perfusion mediated by statins

Desmoglein 2 mutant mice develop cardiac fibrosis and dilation

Desmosomes are cell–cell adhesion sites and part of the intercalated discs, which couple adjacent cardiomyocytes. The connection is formed by the extracellular domains of desmosomal cadherins that are also linked to the cytoskeleton on the cytoplasmic side. To examine the contribution of the desmosomal cadherin desmoglein 2 to cardiomyocyte adhesion and cardiac function, mutant mice were prepared lacking a part of the extracellular adhesive domain of desmoglein 2. Most live born mutant mice presented normal overall cardiac morphology at 2 weeks. Some animals, however, displayed extensive fibrotic lesions. Later on, mutants developed ventricular dilation leading to cardiac insufficiency and eventually premature death. Upon histological examination, cardiomyocyte death by calcifying necrosis and replacement by fibrous tissue were observed. Fibrotic lesions were highly proliferative in 2-week-old mutants, whereas the fibrotic lesions of older mutants showed little proliferation indicating the completion of local muscle replacement by scar tissue. Disease progression correlated with increased mRNA expression of c-myc, ANF, BNF, CTGF and GDF15, which are markers for cardiac stress, remodeling and heart failure. Taken together, the desmoglein 2-mutant mice display features of dilative cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy, an inherited human heart disease with pronounced fibrosis and ventricular arrhythmias that has been linked to mutations in desmosomal proteins including desmoglein 2

Lovastatin Protects against Experimental Plague in Mice

Background: Plague is an ectoparasite-borne deadly infection caused by Yersinia pestis, a bacterium classified among the group A bioterrorism agents. Thousands of deaths are reported every year in some African countries. Tetracyclines and cotrimoxazole are used in the secondary prophylaxis of plague in the case of potential exposure to Y. pestis, but cotrimoxazole-resistant isolates have been reported. There is a need for additional prophylactic measures. We aimed to study the effectiveness of lovastatin, a cholesterol-lowering drug known to alleviate the symptoms of sepsis, for plague prophylaxis in an experimental model. Methodology: Lovastatin dissolved in Endolipide was intraperitoneally administered to mice (20 mg/kg) every day for 6 days prior to a Y. pestis Orientalis biotype challenge. Non-challenged, lovastatin-treated and challenged, untreated mice were also used as control groups in the study. Body weight, physical behavior and death were recorded both prior to infection and for 10 days post-infection. Samples of the blood, lungs and spleen were collected from dead mice for direct microbiological examination, histopathology and culture. The potential antibiotic effect of lovastatin was tested on blood agar plates. Conclusions/Significance: Lovastatin had no in-vitro antibiotic effect against Y. pestis. The difference in the mortality between control mice (11/15; 73.5%) and lovastatin-treated mice (3/15; 20%) was significant (P,0.004; Mantel-Haensze