337 research outputs found

    Decision support system for the production of miscanthus and willow briquettes

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    The biomass is regarded as a part of renewable energy sources (RES), which can satisfy energy demands. Biomass obtained from plantations is characterized by low bulk density, which increases transport and storage costs. Briquetting is a technology that relies on pressing biomass with the aim of obtaining a denser product (briquettes). In the production of solid biofuels, the technological as well as material variables significantly influence the densification process, and as a result influence the end quality of briquette. This process progresses differently for different materials. Therefore, the optimal selection of process’ parameters is very difficult. It is necessary to use a decision support tool—decision support system (DSS). The purpose of the work was to develop a decision support system that would indicate the optimal parameters for conducting the process of producing Miscanthus and willow briquettes (pre-comminution, milling and briquetting), briquette parameters (durability and specific density) and total energy consumption based on process simulation. Artificial neural networks (ANNs) were used to describe the relationship between individual parameters of the briquette production process. DSS has the form of a web application and is opened from a web browser (it is possible to open it on various types of devices). The modular design allows the modification and expansion the application in the future

    The inward turn of consciousness : gods, metaphors, necessity, and the continued relevance of Greek tragedy

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    This paper was written to examine Greek Tragedy in its entirety, specifically through the playwrights Aeschylus, Sophocles, and Euripides. We focused on the inward turn of consciousness, or the movement from the great gods of Olympus authorizing actions through supra-human forces informing character, to conflicting psychic drives that condition human lives and motivate actions. We looked at the backgrounds of all three playwrights, analyzed each play, and ultimately concluded that Greek Tragedy is still important today. Greek Tragedy remains profoundly relevant today because it tries to explain ourselves, our relationship to others, our relationship to the world, and our relationship to the divine.B.A. (Bachelor of Arts

    ANALYSIS OF RESEARCH TRENDS IN THE FIELD OF MECHANICAL ENGINEERING

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    The work includes a bibliometric analysis of the main topics and research trends within the discipline of Mechanical Engineering. On the basis of analysis of data from the Scopus database, the Applied Mechanics Reviews magazine was chosen, which is the only one conducting scientific activity exclusively in the field of Mechanical Engineering. In the years of analysis (2002-2017), it was pointed out that the main research topics are optimization issues, material engineering and mechanics

    Measuring Quality Beyond Test Scores: The Impact of Regional Context on Curriculum Implementation (in Northern Uganda)

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    Although global initiatives have brought attention to the lack of quality in education systems worldwide; the question remains, how do we implement quality education? Teachers, a vital component of the education process, are not usually included in these global conversations; this results in government initiatives missing key obstacles faced by teachers daily. In this article, we used a rights-based approach to examine the Quality Educators Initiative, specifically its curricular component, as it tries to assist teachers in northern Uganda, an area whose schools and communities are vastly under-resourced and dealing with post-conflict effects. Using a mixed-methods approach, we highlight teachers’ experiences with the National Thematic Curriculum and reveal through our findings that regional contextual factors, and teachers’ voices and changing roles due to these factors, must be taken into consideration when rolling out new education policies

    Endocrine Active Compounds Actions during Neonatal Period: Effect on the Ovary

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    Many female reproductive disorders observed during adulthood originate from the neonatal period, which is a critical stage toward the reproductive potency. Human and animal fertility are determined by the pool of primordial follicles that are established during fetal or neonatal life. The earliest stages of follicle development are under control of a variety of factors, including sex steroids. Neonatal period is a “critical developmental window” in which organisms are susceptible to the environmental chemicals that may affect the reproductive health. Endocrine active compounds (EACs) are found abundantly in the environment and interfere with sex steroids (predominantly androgens and estrogens) by either mimicking or blocking their functions. This review covers the current knowledge about the effects of selected EACs with androgenic (testosterone propionate), anti-androgenic (flutamide), estrogenic (diethylstilbestrol, bisphenol A, 4-tert-octylphenol, phtalates and genistein), anti-estrogenic (ICI 182,780 and parabens), or mixed activity (methoxychlor) on the ovary of neonates, focusing on their effects on the early stages of folliculogenesis. These chemicals have been shown to affect oocyte survival, follicle formation, and growth, as well as steroidogenic functions. The better cognition of mechanisms underlying the long-term consequences of the neonatal EACs exposure may in future lead to an understanding of human health risks and developing prevention strategies

    Bieszczady na sprzedaĹĽ

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    Istota obrony koniecznej w polskich kodeksach karnych

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    The article presents the necessity and the evolution of the institutions of self-defense in the Polish criminal codes of the years 1932, 1969 and 1997. Analyzed are the signs of self-defense in relation to the previous regulations. The study cited the views of eminent legal theorists, judgment and comparison of understanding the institutions in the comments from various years

    Effects of transferrin on aromatase activity in porcine granulosa cells in vitro.

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    Proliferating cells have an absolute requirement for iron, which is delivered by transferrin with subsequent intracellular transport via the transferrin receptor. Recent studies have reported that transferrin plays a crucial role in the local regulation of ovarian function, apart from its iron-binding characteristic. Therefore, the present study was undertaken to explore the possible role of transferrin in porcine granulosa cells function by examining its influence on aromatase activity, the most important indicator of follicular cell differentiation. In the first series of studies, pig granulosa cells isolated from small, immature follicles were cultured in the presence of transferrin alone (10 microg/ml or 100 microg/ml) or with the addition of FSH (100ng/ml). The second series of studies was undertaken to determine transferrin-stimulated granulosa cells ability to aromatize exogenous testosterone (1x10(-7)M). One hour after the establishment of cultures an aromatase inhibitor CGS16949A was added to test its influence on estradiol production. After 48 hours, cultures were terminated and cells were processed for immunocytochemical staining of aromatase. Media were frozen for further estradiol level analysis. Positive immunostaining for aromatase was found in all granulosa cell cultures. The intensity of immunostaining was always stronger in cultures supplemented with FSH whereas the addition of transferrin had no effect. Granulosa cells in vitro synthesized the highest amount of estradiol after the addition of FSH and exogenous testosterone as measured radioimmunologically. Concomitant treatment with FSH and transferrin caused an inhibition of FSH-stimulated aromatase activity. The production of estradiol also declined in the presence of FSH, testosterone and transferrin. This study demonstrates that transferrin had a dose-dependent inhibitory effect on FSH-stimulated aromatase activity, which was confirmed by radioimmunoassay. Our results indicate that transferrin may be an important factor in the regulation of granulosa cell diferentiation

    ANALYSIS OF RESEARCH TRENDS IN AGRICULTURAL ENGINEERING

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    Nowadays it is necessary to define actual global research trends in disciplines in order to determine the major research topics, discoveries and global scientific networks. The goal of the work was to determine the main topics and research trends in agricultural engineering. For this caser he method of modified bibliometric analysis was applied. Such analysis of the keywords frequency occurrence and the links between the keywords in Biosystems Engineering Journal shows that in the three analysed periods, certain keywords invariably remain dominant. These are “model”, “system” or “systems”, “temperature” and “water”. The highest number of publications was qualified for the CIGR section: Information Technology. It can be, therefore, stated that in the recent period the most intensively developing researches were dedicated to the application of IT tools in creation various types of models, allowing to simulate and optimize agricultural processes. A majority of publications covered decision-making support (Decision Support Systems), image analysis application, and automation of agricultural processes

    Thermal treatment of biomass : a bibliometric analysis : the torrefaction case

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    The aim of the paper was to summarize and discuss current research trends in biomass thermal treatment (torrefaction process). Quantitative analyses were carried out, in which the main countries, research units and scientists were indicated. The analysis showed a clear upward trend in number of publications after 2010. Most scientists on selected topics come from China, USA, Canada, South Korea, Republic of China, Poland (Web od Science—Core Collection (WoS-CC) and Scopus databases). Quantitative analysis also showed that the most relevant WoS-CC categories in the summary are: Energy Fuels, Engineering Chemical, Agricultural Engineering, Biotechnology Applied Microbiology and Thermodynamics and Scopus Subject area: Energy, Chemical Engineering, Environmental Science, Engineering and Chemistry. Thematic analysis included research topics, process parameters and raw materials used. Thematic groups were separated: torrefaction process (temp.: 150–400 °C), hydrothermal carbonization process (HTC) (temp: 120–500 °C), pyrolysis process (temp.: 200–650 °C) and gasification and co-combustion process (temp.: 350–1600 °C). In the years 2015–2019, current research topics were: new torrefaction technologies (e.g., HTC), improvement of the physico-mechanical, chemical and energetic properties of produced fuel as well as the use of torrefied biomass in the process of pyrolysis, gasification and co-combustion. The raw materials used in all types of biomass thermal treatment were: energy crops, wood from fast-growing and exotic trees, waste from the agri-food industry, sewage sludge and microalgae
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