Чисельне моделювання термо-напружено-деформованого стану елементів у процесі 3D друку

The paper is devoted to the assessment of the thermo-stress-strain state of elements of structures obtained by 3D printing using FDM (Fusing Deposition Modeling) technology. Three stages of solving this problem are considered: (1) - mathematical formulation of the problem, that includes universal balance relations, constitutive equations of mechanical behavior of the material and is based on the model of growing bodies; (2) the technique of finite-element solution with increasing mesh due to the addition of new elements; (3) - study of a specific problem of growing plate-like element by polymer PLA (polylactide) with temperature-dependent physical properties. Options of deposed layers of different thickness are considered. The residual stress-strain state of the body has a two-scale structure, which reflects the change of state characteristics in the scale of body size, as well as the thickness of the layers. As the thickness of the layers increases, the average values of the residual stresses decrease, but the amplitude of the stress fluctuations along the thickness of the layer slightly increase. Pages of the article in the issue: 70 - 75 Language of the article: UkrainianРобота присвячена оцінці термо-напружено-деформованого стану виробів, отриманих методом 3D друку за технологією FDM (Fusing Deposition Modeling). Розглянуто три стадії розв‘язання цієї задачі: (1) – математична постановка задачі, що базується на моделі тіл, що ростуть; (2) методика скінченно-елементного розв‘язку задачі; (3) – дослідження конкретної задачі з метою виявлення закономірностей термомеханічних процесів при 3D друку

ГЕПАТИТ Е: НОВАЯ ПРОБЛЕМА ТРАНСПЛАНТОЛОГИИ?

Hepatitis E is enterically transmitted infection and is the cause of outbreaks and sporadic cases. Disease was originally registered only in the developing subtropical and tropical countries and has been connected with I or II genotypes of hepatitis E virus (HEV). Later sporadic hepatitis E has been registered in a number of the deve- loped countries of Western Europe, North America, South East Asia and Ocenia. These cases have been caused, as a rule, by III or IV genotypes of HEV. Until recently it was considered, that the disease is usually self-limited except pregnant women in which HEV infection is more severe, often leading to fulminant liver failure and death in a significant proportion of patients. The current review represents the analysis of publications of the last years reflecting the facts that HEV infection may develop in immunosuppressed patients, in particular in liver transplant recipients, who may then serve as long-term carriers of the virus with progression to cirrhosis. The information on the first attempts of antiviral therapy in these patients is presented. Гепатит Е относится к группе энтеральных гепатитов и может иметь характер как эпидемической, так и спорадической инфекции. Заболевание первоначально регистрировалось только в развивающихся суб- тропических и тропических странах и было связано с заражением I или II генотипами вируса. Позже спо- радический гепатит Е был зарегистрирован в ряде развитых стран Западной Европы, Северной Америки, Юго-Восточной Азии и Океании. Эти случаи были обусловлены инфицированием, как правило, III или IV генотипами вируса гепатита Е (HEV). До недавнего времени считалось, что течение болезни имеет об- ратимый характер и обычно завершается выздоровлением за исключением случаев заражения женщин на поздних сроках беременности, у которых была описана возможность развития фульминантного гепатита. Настоящий обзор посвящен анализу публикаций последних лет, отражающих течение HEV-инфекции у больных с иммунодефицитом, в частности у реципиентов трансплантатов солидных органов, для кото- рых совсем недавно была показана возможность хронизации болезни и трансформации ее в цирроз пече- ни. Представлена информация о первых попытках противовирусной терапии у этих больных.

HEPATITIS E: А NEW PROBLEM IN TRANSPANTOLOGY?

Hepatitis E is enterically transmitted infection and is the cause of outbreaks and sporadic cases. Disease was originally registered only in the developing subtropical and tropical countries and has been connected with I or II genotypes of hepatitis E virus (HEV). Later sporadic hepatitis E has been registered in a number of the deve- loped countries of Western Europe, North America, South East Asia and Ocenia. These cases have been caused, as a rule, by III or IV genotypes of HEV. Until recently it was considered, that the disease is usually self-limited except pregnant women in which HEV infection is more severe, often leading to fulminant liver failure and death in a significant proportion of patients. The current review represents the analysis of publications of the last years reflecting the facts that HEV infection may develop in immunosuppressed patients, in particular in liver transplant recipients, who may then serve as long-term carriers of the virus with progression to cirrhosis. The information on the first attempts of antiviral therapy in these patients is presented