168 research outputs found

    Microstructural and physical aspects of heat treated wood, part 1: softwood

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    Heat treatment of wood is an effective method to improve the dimensional stability and durability against biodegradation. Optimisation of a two-stage heat treatment process at relatively mild conditions (<200°C) and its effect on the anatomical structure of softwoods were investigated by means of a light and scanning electron microscopic analysis. Heat treatment did have an effect on the anatomical structure of wood, although this depends on the wood species considered and on the process method and conditions used. Softwood species with narrow annual rings and/or an abrupt transition from earlywood into latewood were sensitive to tangential cracks in the latewood section. Radial cracks occurred mainly in impermeable wood species such as Norway spruce, caused by large stresses in the wood structure during treatment. Sapwood of treated pine species revealed some damage to parenchyma cells in the rays and epithelial cells around resin canals, whereas this phenomenon has not been noticed in the heartwood section. Treated radiata pine resulted in a very open and permeable wood structure limiting the applications of this species. Broken cell walls perpendicular to the fibre direction resulting in transverse ruptures have been noticed in treated softwood species. This contributes to abrupt fractures of treated wood as observed in bending tests which can lead to considerably different failure behavior after impact or mechanical stress. In some treated softwood species maceration (small cracks between tracheids) was noticed after heat treatment. Heat treatment did not cause damage to the ray parenchyma pit membranes, bordered pits and large window pit membranes; the margo fibrils appeared without damage. Compared to the other softwood timbers tested European grown Douglas fir was the timber that stands heat treatment the best

    Analysis of Safety Concerns on Herbal Products with Assumed Phytoestrogenic Activity

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    Phytoestrogens (PEs) are plant-based compounds that can interact with estrogen receptors and are mainly used to treat menopausal complaints. However, the safety of products with assumed phytoestrogenic activity is not fully understood. This study aimed to identify plant species with assumed phytoestrogenic activity, review existing literature on their use and safety, and critically evaluate adverse reaction (AR) reports of single-herb, multi-herb, and mixed-multiple products, as submitted to the Netherlands Pharmacovigilance Centre Lareb and to VigiBase of the World Health Organization (WHO). In the Lareb database, the most commonly reported plant species to cause ARs (total of 67 reports) were Actaea racemosa L. (black cohosh) (47.8%), Humulus lupulus L. (hops) (32.8%), and Glycine max (L.) Merr. (soybean) (22.4%). In the VigiBase database (total of 21,944 reports), the top three consisted of Glycine max (L.) Merr. (71.4%), Actaea racemosa L. (11.6%), and Vitex agnus-castus L. (chaste tree) (6.4%). In the scoping review (total of 73 articles), Actaea racemosa L. (30.1%), Glycine max (L.) Merr. (28.8%), and Trifolium pratense L. (13.7%) were the most frequently mentioned plant species. ARs were most frequently reported in the system organ classes "gastrointestinal disorders", "skin and subcutaneous tissue disorders", "reproductive system and breast disorders", and "general disorders and administration site conditions". Furthermore, from the scoping review, it appeared that the use of products with assumed phytoestrogenic activity was associated with postmenopausal bleeding. It was concluded that, while the potential benefits of products with assumed phytoestrogenic activity have been extensively pursued, the potential occurrence of ARs after using these products is less well understood. This study highlights the need for further investigation and careful monitoring of these products to better understand their effects and ensure the safety and well-being of individuals using them. </p

    Тоталітарні режими: ідеологічне обґрунтування цілей, форм і методів володарювання

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    Розглянуто теоретичні аспекти взаємовпливу ідеології та конкретно-історичних форм володарювання на прикладі фашизму і націонал-соціалізму. Проаналізована сутність праворадикальної ідеології, причини її виникнення, форми впливу та можливі загрози у контексті демократичного розвитку.The article researches the theoretical aspects of the mutual influence of an ideology and particular-historical forms of reigning on the Fascism's and the National-Socialism's example. The author analyzes the essence of right- radical ideology, the reasons of its appearance, forms of its influence as well as probable threats in the context of democratic development

    Microstructural and physical aspects of heat treated wood. Part 2. Hardwoods

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    Heat treatment of wood is an effective method to improve the dimensional stability and durability against biodegradation. Optimisation of a two-stage heat treatment process at relatively mild conditions (&lt;200° C) and its effect on the anatomical structure of hardwoods were investigated by means of a light and scanning electron microscopic analysis. Hardwood species such as beech and poplar, were predominantly sensitive to collaps of the vessels and some deformation of the libriform fibres directly near the vessels. In treated beech and birch radial cracks were observed near the rays. Optimisation of the heat treatment process conditions including the application of a steam hydro thermolysis stage reduced such damages to a minimum. Broken cell walls perpendicular to the fibre direction resulting in transverse ruptures has been noticed in heat treated hardwood species. This contributes to abrupt fractures of treated wood as observed in bending tests which can lead to considerably different failure behavior after impact of mechanical stress. In some treated hardwood species maceration (small cracks between tracheids) was noticed after heat treatment. Heat treatment did not reveal damage to the ray parenchyma pit membranes, bordered pits and large window pit membranes; and the margo fibrils appeared without damage

    Microstructural and physical aspects of heat treated wood. Part 1. Softwoods

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    Heat treatment of wood is an effective method to improve the dimensional stability and durability against biodegradation. Optimisation of a two-stage heat treatment process at relatively mild conditions (&lt;200° C) and its effect on the anatomical structure of softwoods were investigated by means of a light and scanning electron microscopic analysis. Heat treatment did have an effect on the anatomical structure of wood, although this depends on the wood species considered and on the process method and conditions used. Softwood species with narrow annual rings and/or an abrupt transition from earlywood into latewood were sensitive to tangential cracks in the latewood section. Radial cracks occurred mainly in impermeable wood species such as Norway spruce, caused by large stresses in the wood structure during treatment. Sapwood of treated pine species revealed some damage to parenchyma cells in the rays and epithelial cells around resin canals, whereas this phenomenon has not been noticed in the heartwood section. Treated radiata pine resulted in a very open and permeable wood structure limiting the applications of this species. Broken cell walls perpendicular to the fibre direction resulting in transverse ruptures have been noticed in treated softwood species. This contributes to abrupt fractures of treated wood as observed in bending tests which can lead to considerably different failure behavior after impact or mechanical stress. In some treated softwood species maceration (small cracks between tracheids) was noticed after heat treatment. Heat treatment did not cause damage to the ray parenchyma pit membranes, bordered pits and large window pit membranes; the margo fibrils appeared without damage. Compared to the other softwood timbers tested European grown Douglas fir was the timber that stands heat treatment the best

    Optimisatoin tactics of disgnostic and treatment of women of reproductive age with dysplastic lesions of sguamosus cervical epitelium and hyperproliferative diseases of the uterus

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    Cervical cancer frequency ranks second in the structure of cancer among women. HPV is the only proven etiological factor of precancerous lesions and cervical cancer.Given the increasing frequency of adenomyosis and leiomyoma of the uterus and pathology of the cervical epithelium in women with unfulfilled reproductive function and the extension age limits of the reproductive period, organ-preserving methods of treatmentof these pathological conditions is a main priority in gynecology.The aim of this research was to develop approaches to the treatment of cervical pathology in women with hyperproliferative diseases of the uterus
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