85 research outputs found

    Double-blind, placebo-controlled evaluation of grass pollen specific immunotherapy with oral drops administered sublingually or supralingually

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    SummaryForty-one patients suffering from grass pollen allergy underwent specific immunotherapy with standardized allergen extract consisting of six grass pollens (H-Al per os) administered either sublingually or supralingually for one year. In order to investigate clinical and immunological changes induced by the administration of allergens via the oral mucosa, the double-blind, placebo-controlled, randomized design of the trial with 30 other patients enrolled in placebo groups was applied.Specific immunotherapy with oral drops administered sublingually or supralingually was performed in the same way, keeping the drops under or on the tongue, respectively, for 1–2min before swallowing them; at the end of the trial the cumulative dose of the allergen was almost 20 times higher than that of the subcutaneous therapy with corresponding allergen preparation. Data about symptoms scores and drugs intake during grass pollen season, as well as skin reactivity, levels of specific IgG and IgE antibodies, before the study and after the study's completion, were obtained.It was found that both routes of administration are effective according to subjective clinical parameters and drug consumption, with a highly significant reduction of symptoms and drug intake favoring sublingual administration where a reduction of more than 60% was achieved. Only sublingual active group showed a significant increase in Dactylis glomerata-specific IgG serum levels. Adverse effects were limited to a small number of generally mild local and/or systemic reactions.The results suggest that the administration of allergens via the oral mucosa is safe and clinically effective, favoring the sublingual rather than supralingual route

    Control and Supervision of Wind Energy Conversion Systems

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    This paper is about a PhD thesis and includes the study and analysis of the performance of an onshore wind energy conversion system. First, mathematical models of a variable speed wind turbine with pitch control are studied, followed by the study of different controller types such as integer-order controllers, fractional-order controllers, fuzzy logic controllers, adaptive controllers and predictive controllers and the study of a supervisor based on finite state machines is also studied. The controllers are included in the lower level of a hierarchical structure composed by two levels whose objective is to control the electric output power around the rated power. The supervisor included at the higher level is based on finite state machines whose objective is to analyze the operational states according to the wind speed. The studied mathematical models are integrated into computer simulations for the wind energy conversion system and the obtained numerical results allow for the performance assessment of the system connected to the electric grid. The wind energy conversion system is composed by a variable speed wind turbine, a mechanical transmission system described by a two mass drive train, a gearbox, a doubly fed induction generator rotor and by a two level converter

    Numerical investigation of three types of space and time fractional Bloch-Torrey equations in 2D

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    Recently, the fractional Bloch-Torrey model has been used to study anomalous diffusion in the human brain. In this paper, we consider three types of space and time fractional Bloch-Torrey equations in two dimensions: Model-1 with the Riesz fractional derivative; Model-2 with the one-dimensional fractional Laplacian operator; and Model-3 with the two-dimensional fractional Laplacian operator. Firstly, we propose a spatially second-order accurate implicit numerical method for Model-1 whereby we discretize the Riesz fractional derivative using a fractional centered difference. We consider a finite domain where the time and space derivatives are replaced by the Caputo and the sequential Riesz fractional derivatives, respectively. Secondly, we utilize the matrix transfer technique for solving Model-2 and Model-3. Finally, some numerical results are given to show the behaviours of these three models especially on varying domain sizes with zero Dirichlet boundary conditions

    European beech stem diameter grows better in mixed than in mono-specific stands at the edge of its distribution in mountain forests

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    Recent studies show that several tree species are spreading to higher latitudes and elevations due to climate change. European beech, presently dominating from the colline to the subalpine vegetation belt, is already present in upper montane subalpine forests and has a high potential to further advance to higher elevations in European mountain forests, where the temperature is predicted to further increase in the near future. Although essential for adaptive silviculture, it remains unknown whether the upward shift of beech could be assisted when it is mixed with Norway spruce or silver fir compared with mono-specific stands, as the species interactions under such conditions are hardly known. In this study, we posed the general hypotheses that the growth depending on age of European beech in mountain forests was similar in mono-specific and mixed-species stands and remained stable over time and space in the last two centuries. The scrutiny of these hypotheses was based on increment coring of 1240 dominant beech trees in 45 plots in mono-specific stands of beech and in 46 mixed mountain forests. We found that (i) on average, mean tree diameter increased linearly with age. The age trend was linear in both forest types, but the slope of the age–growth relationship was higher in mono-specific than in mixed mountain forests. (ii) Beech growth in mono-specific stands was stronger reduced with increasing elevation than that in mixed-species stands. (iii) Beech growth in mono-specific stands was on average higher than beech growth in mixed stands. However, at elevations > 1200 m, growth of beech in mixed stands was higher than that in mono-specific stands. Differences in the growth patterns among elevation zones are less pronounced now than in the past, in both mono-specific and mixed stands. As the higher and longer persisting growth rates extend the flexibility of suitable ages or size for tree harvest and removal, the longer-lasting growth may be of special relevance for multi-aged silviculture concepts. On top of their function for structure and habitat improvement, the remaining old trees may grow more in mass and value than assumed so far.The authors would like to acknowledge networking support by the COST (European Cooperation in Science and Technology) Action CLIMO (Climate-Smart Forestry in Mountain Regions—CA15226) financially supported by the EU Framework Programme for Research and Innovation HORIZON 2020. This publication is part of a project that has received funding from the European Union’s HORIZON 2020 research and innovation programme under the Marie Skłodowska-Curie Grant Agreement No 778322. Thanks are also due to the European Union for funding the project ‘Mixed species forest management. Lowering risk, increasing resilience (REFORM)’ (# 2816ERA02S under the framework of Sumforest ERA-Net). Further, we would like to thank the Bayerische Staatsforsten (BaySF) for providing the observational plots and to the Bavarian State Ministry of Food, Agriculture, and Forestry for permanent support of the Project W 07 ‘Long-term experimental plots for forest growth and yield research’ (#7831-26625-2017). We also thank the Forest Research Institute, ERTI Sárvár, Hungary, for assistance and for providing observational plots. Furthermore, our work was partially supported by the SRDA via Project No. APVV-16-0325 and APVV-15-0265, the Ministry of Science and Higher Education of the Republic of Poland, the Project “EVA4.0” No. CZ.02.1.01/0.0/0.0/16_019/0000803 funded by OP RDE and the Project J4-1765 funded by the Slovenian Research Agency and also by the Bulgarian National Science Fund (BNSF) and the Project No. DCOST 01/3/19.10.2018

    The productivity of mixed mountain forests comprised of Fagus sylvatica, Picea abies, and Abies alba across Europe

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    11 Pág.Mixed mountain forests of European beech (Fagus sylvatica L.), Norway spruce (Picea abies (L.) Karst), and silver fir (Abies alba Mill.) cover a total area of more than 10 million hectares in Europe. Due to altitudinal zoning, these forests are particularly vulnerable to climate change. However, as little is known about the long-term development of the productivity and the adaptation and mitigation potential of these forest systems in Europe, reliable information on productivity is required for sustainable forest management. Using generalized additive mixed models this study investigated 60 long-term experimental plots and provides information about the productivity of mixed mountain forests across a variety of European mountain areas in a standardized way for the first time. The average periodic annual volume increment (PAI) of these forests amounts to 9.3 m3ha-1y-1. Despite a significant increase in annual mean temperature the PAI has not changed significantly over the last 30 years. However, at the species level, we found significant changes in the growth dynamics. While beech had a PAI of 8.2 m3ha-1y-1 over the entire period (1980-2010), the PAI of spruce dropped significantly from 14.2 to 10.8 m3ha-1y-1, and the PAI of fir rose significantly from 7.2 to 11.3 m3ha-1y-1. Consequently, we observed stable stand volume increments in relation to climate change.T.H. received scholarship from the Rudolf and Helene Glaser Foundation organized in the ‘Stifterverband für die deutsche Wissenschaft’. This study was supported by the grant ‘EVA4.0’, No. CZ.02.1.01/0.0/0.0/16_019/0000803 financed by OP RDE and the Ministry of Science and Higher Education of The Republic of Poland.Peer reviewe

    Control of Fractional-Order Nonlinear Systems: A Review

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    This paper deals with the control of the fractional-order nonlinear systems. A list of the control strategies as well as synchronization of the chaotic systems is presented. An illustrative example of sliding mode control (SMC) of the fractional-order (commensurate and incommensurate) financial system is described and commented together with the simulation results
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