Автоматическая генерация семантически связного текста методами машинного обучения

Целями данной работы являются: проведение аналитического обзора методов генерации семантически связного текста, реализация алгоритмов машинного обучения для генерации семантически связного текста, проведение сравнения с аналогичными решениями. В результате исследования: был проведен анализ алгоритмов генерации текста. Проведен поиск выборок данных для обучения реализованных алгоритмов. Реализованы: автоэнкодер, два подхода к генерации текста на основе RNN, упрощенная реализация SeqGAN (без реализации алгоритма Монте-Карло). Приведены результаты обучения и тестирования. Проведено обучение и тестирование реализованных алгоритмов и нейронной сети LeakGAN. Проведена оценка качества нейронных сетей LSTM и SeqGAN по метрике BLEU. Проведено сравнение с аналогичными решениями.The objectives of this work are: to conduct an analytical review of methods for generating a semantically coherent text, implement machine learning algorithms to generate a semantically coherent text, and compare with similar solutions. As a result of the study: an analysis of the text generation algorithms was carried out. A search was made of data samples for training implemented algorithms. Implemented: auto-encoder, two approaches to generating text based on RNN, simplified implementation of SeqGAN (without implementation of the Monte Carlo algorithm). The results of training and testing. Training and testing of implemented algorithms and LeakGAN was conducted. The quality of neural networks LSTM and SeqGAN was assessed using the BLEU metric. Compared with similar solutions

Пандемия COVID-19 - чрезвычайная ситуация в сфере здравоохранения

В статье представлена информация о возникновении пандемии коронавируса, строении коронавируса, способах заражения. Описаны меры профилактики, приведены данные о разработанных вакцинах против коронавируса.The article provides information about the occurrence of the coronavirus pandemic, the structure of the coronavirus, and methods of infection. Prevention measures are described, and data on developed coronavirus vaccines are provided

Study of the dynamics of the accumulation of chemical elements by moss-transplants

Artificial retinal detachment is increasingly used in submacular surgery. However, overcoming physiological retinal adhesiveness by subretinal fluid injection is suspected to cause cellular damage and thus to limit visual rehabilitation. This experimental study was designed to examine the ultrastructural changes induced by retinal detachment under vitrectomy conditions and to evaluate factors that reduce adhesiveness and minimize cellular damage

Long-term transgene expression in the RPE after gene transfer with a high-capacity adenoviral vector. Invest Ophthalmol Vis Sci 2002

PURPOSE. To analyze duration of gene expression in the retinal pigment epithelium (RPE) in immunocompetent animals after gene transfer with a high-capacity adenoviral (HC-Ad) vector. METHODS. An HC-Ad vector was constructed to express the enhanced green fluorescence protein (EGFP) from the human CMV promoter. This vector (HC-AdFK7) was used to transduce rat RPE cells in cell culture and after subretinal injection in vivo in adult immunocompetent Wistar rats. In cell culture, expression of EGFP was analyzed by fluorescence microscopy. In vivo expression was monitored by scanning laser ophthalmoscopy and stereo fluorescence microscopy. After enucleation of the eyes, immunohistochemical and morphologic analyses by fluorescence light microscopy and electron microscopy were performed. RESULTS. In vitro, RPE cells were efficiently transduced with HC-AdFK7. Expression persisted for the observation time of 8 weeks. In vivo, the RPE was efficiently transduced with low doses of HC-AdFK7. EGFP synthesis was confirmed by antibody staining and found to be stable for the complete study period of 6 months. The neuroretina was well preserved over areas of subretinal vector administration, and significant morphologic changes were not detected. There was no accumulation of inflammatory T cells or macrophages. CONCLUSIONS. In contrast to previous results with earlier generation adenoviral vectors, subretinal injection of an HC-Ad vector in immunocompetent rats resulted in long-term transgene expression without evidence of adverse immune reactions or significant toxicity, probably because of the absence of expression of the viral gene from this vector. Thus, HC-Ad vectors are suitable for the treatment of eye disorders that require durable gene expression in the RPE. (Invest Ophthalmol Vis Sci. 2002; 43:1965-1970 S everal hereditary and acquired retinal diseases are known to primarily affect the retinal pigment epithelium (RPE). The RPE is involved in retinol metabolism and in photoreceptor outer segment phagocytosis. In addition, in RPE cells several trophic and antiangiogenic factors are produced that are essential for the function and the integrity of the retina (for review, see Ref. 1). Several types of retinitis pigmentosa are caused by mutations in genes that are exclusively expressed in the RPE and not in the photoreceptor cells. 2-4 Best disease is an example of a primary disorder of the RPE. 5 Age-related macular degeneration (AMD) is a very common multifactorial disorder that affects the RPE. In industrialized countries AMD is the leading cause of blindness in individuals more than 65 years of age. 6 Visual impairment is probably caused by macular photoreceptor degeneration due to progressive changes in the RPE and the choriocapillaris. 7 Formation of fibrovascular membranes in the macular region complicates the natural course of the disease and leads to sudden and severe visual loss. 8 Treatment options for this complication, known as choroidal neovascularization (CNV), include laser photocoagulation, photodynamic therapy, and submacular surgery. 9 After surgical excision of areas of CNV, invariably there is additional damage to the RPE. 10 The disappointing long-term results of current therapies for AMD or genetic RPE disorders indicate that there is an urgent need for the development of new treatment strategies. Gene therapy has a significant potential for the treatment of retinal disorders. Viral vectors, derived from adenovirus, adenoassociated virus (AAV) or from lentivirus have been successfully used in preclinical models to deliver reporter or therapeutic genes into the different cell layers of the retina. Adenovirus serotype 5-based vectors have been demonstrated to efficiently and selectively transduce the RPE after subretinal vector injection