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Summary

In or. 25 Demosthenes compares Aristogeiton to a watchdog who, instead of defending the sheeps, attacks and tears them to pieces. This picture seems not to be common in Attic rhetoric, but is occurs in Plat. Rep. 416a, where Socrates warns about the danger that the most popular orators, in betrayal of their former task, assault the demos and eventually become tyrants. This platonic passage confers a new meaning to the Demosthenic statement and suggests the possibility that Aristogeiton aimed at tyranny. Hence the nomos, which only can control physis, protects society from the worst human vices (poneria, hybris and anaideia), and represents the most effective defence of democracy.

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Authors: Stefano Dugheri, Giorgio Marrubini, Nicola Mucci, Giovanni Cappelli, Alessandro Bonari, Ilenia Pompilio, Lucia Trevisani and Giulio Arcangeli

Abstract

Sample pretreatment is one of the most crucial and error-prone steps of an analytical procedure; it consents to improve selectivity and sensitivity by sample clean-up and pre-concentration. Nowadays, the arousing interest in greener and sustainable analytical chemistry has increased the development of microextraction techniques as alternative sample preparation procedures. In this review, we aimed to show two different categorizations of the most used micro-solid-phase extraction (μSPE) techniques. In essence, the first one concerns the solid-phase extraction (SPE) sorbent selection and structure: normal-phase, reversed-phase, ion-exchange, mixed-mode, molecular imprinted polymer, and special techniques (e.g., doped cartridges for specific analytes). The second is a grouping of the commercially available μSPE products in categories and sub-categories. We present every device and technology into the classifications paying attention to their historical development and the actual state of the art. So, this study aims to provide the state-of-the-art of μSPE techniques, highlighting their advantages, disadvantages, and possible future developments in sample pretreatment.

Open access

Abstract:

Phosphorus is a major substance that is needed especially for agricultural production or for the industry. At the same time it is an important component of wastewater. At present, the waste management priority is recycling and this requirement is also transferred to wastewater treatment plants. Substances in wastewater can be recovered and utilized. In Europe (in Germany and Austria already legally binding), access to phosphorus-containing sewage treatment is changing. This paper dealt with the issue of phosphorus on the sewage treatment plant in Nitra. There are several industrial areas in Nitra where record major producers in phosphorus production in sewage. The new wastewater treatment plant is built as a mechanicalbiological wastewater treatment plant with simultaneous nitrification and denitrification, sludge regeneration, an anaerobic zone for biological phosphorus removal at the beginning of the process and chemical phosphorus precipitation. The sludge management is anaerobic sludge stabilization with heating and mechanical dewatering of stabilized sludge and gas management. The aim of the work was to document the phosphorus balance in all parts of the wastewater treatment plant - from the inflow of raw water to the outflow of purified water and the production of excess sludge. Balancing quantities in the wastewater treatment plant treatment processes provide information where efficient phosphorus recovery could be possible. The mean daily value of P tot is approximately 122.3 kg/day of these two sources. The mean daily value of P tot is approximately 122.3 kg/day of these two sources. There are also two outflows - drainage of cleaned water to the recipient - the river Nitra - 9.9 kg Ptot/day and Ptot content in sewage sludge - about 120.3 kg Ptot/day - total 130.2 kg Ptot/day.

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Authors: Kristóf Roland Horváth and István Kistelegdi

Abstract:

First Hungarian Active House refurbishment won the Active House Award and the Energy Globe Hungary prize in 2017. This paper provides insight into the renewal design process of the typical home from the 70’s under disadvantageous site conditions. Dynamic thermal simulations helped to gain insight into space organization and building envelope concepts and their effects on comfort and energy performance. The Active House Standard was applied to evaluate the calculation results. The most advantageous concept was selected for final design elaboration and construction. The implemented building proved that in the refurbishment process it is possible to achieve highest level of efficiency in operation energy consumption with positive yearly balance by simultaneously being able to rearrange the complete interior space and as a consequence the building shape and envelope into a competitive design at international level.

Open access
Authors: Ádám Remport, Zsuzsanna Gerlei, Orsolya Cseprekál, László Wagner, Katalin Földes, Adrienn Marton, Attila Patonai, Szilárd Török, Anita Haboub-Sandil, Marina Varga, Attila Doros, Anikó Smudla, János Fazakas and László Kóbori

Absztrakt:

Az új koronavírus okozta COVID–19-járvány kihívást jelent a szervátültetett betegek ellátását illetően is, ezért lényegesnek tartjuk az ezzel kapcsolatos friss ismeretek megosztását a hazai ellátásban dolgozók számára. Nagyobb esetszámmal májátültetettekről még nincsenek adatok az irodalomban, vesetranszplantáltak esetén azonban a spanyol és a francia adatbázisok 18,6%-os és 13%-os halálozásról számoltak be, ami kissé magasabb az ottani átlagpopulációénál. Tünetmentes esetekben SARS-CoV-2-pozitív PCR-eredmény birtokában nem szükséges a transzplantáltak immunszuppresszív terápiáján változtatni, azonban láz, gastrointestinalis vagy légúti tünetek kialakulását követően a mikofenolsav és mTOR-gátló készítmények elhagyása javasolt, és a kalcineurininhibitorok vérszintjét a legalacsonyabb effektív szintre kell csökkenteni. Tüdőkárosodás észlelését követően vesetranszplantáltak esetében a kalcineurininhibitorokat is le kell állítani, míg a májtranszplantáltak esetében a dózis csökkentése szükséges a fenntartó kortikoszteroid mellett. Ez utóbbi dózisának emelése szükséges hyperinflammatiós szindróma (HIS) kialakulásakor. A HIS terápiás befolyásolására transzplantáltakban is sikerrel lehet alkalmazni az IL1- és IL6-gátló monoklonális antitesteket. Célzott vírusellenes készítmény nem áll rendelkezésre, a legszerencsésebb, ha a beteg bevonható a remdesivir vagy a favipiravir klinikai vizsgálatába. A hidroxiklorokin transzplantáltaknak is adható, bár hatékonysága és biztonságossága kérdésessé vált. A lopinavir/ritonavir kombináció a kalcineurininhibitorokkal fennálló súlyos gyógyszerkölcsönhatás miatt nem adható. A SARS-CoV-2 cytopathiás hatása endotheldiszfunkciót okoz, amely prokoaguláns állapot kialakulásához vezet, emellett megváltozik a renin-angiotenzin-aldoszteron rendszer egyensúlya is. Fontos ezért a betegek kezelése során a thrombosisprofilaxis korai elkezdése alacsony molekulasúlyú heparinnal és alacsony dózisú acetilszalicilsavval. Az angiotenzinkonvertálóenzim-gátló (ACEI) és az angiotenzin-II-receptor-antagonista (ARB) terápiára beállított betegek kezelését a COVID–19 miatt nem szabad abbahagyni. Orv Hetil. 2020; 161(32): 1310–1321.

Open access

Abstract:

During sketch design stage for the new block of the University of Pécs, Medical School comfort and lighting simulations were applied to quantify optimization strategies. Simulation cases about shading possibilities, façade glazing ratios and internal heat storage masses evaluate the impact of illumination, solar gains, loads and heat transmission on visual and thermal comfort. The goal was to select the most favorable comfort, coupled with maximum reduction of investment costs. Concepts represent 14% (shading), 10% (reduced wall-window ratio), 11% (slabs without suspended ceilings), and 17% (combined wall-window ratio and thermal mass) improvement in thermal comfort performance, and it was proposed for further design.

Open access

Abstract:

The aim of the research is to make a comparison between system integrated measurement technologies in the field of engineering education in order to the students getting more detailed knowledge about the high level problem solving. A comparative case study was conducted with 3 different types of systems, as follows: Beckhoff, National Instruments, and HBM. The criteria of the systems are determined based on experience and the importance level of them was calculated by preference matrix. The ranks of the alternatives are calculated by Kesselring method, which provides the effectiveness value of the systems compared to the benchmark. The result of the paper shows a suitable method for selecting engineering systems.

Open access

Abstract:

In wireless sensors networks, data are sensed and recorded as databases, and then acceded by relational queries. Joins are queries that are largely used. Joins collect data from several nodes’ table. These are operations that typically consume a lot of energy because they generate a large number of messages in the network. Researchers worked to decrease this consumed energy. Many strategies were proposed in this way, but most of them addressed only binary joins. N-way joins received few interests. N-way joins perform join operations between more than two tables. They cause greater energy consumption. Additionally, the number of execution order is very important; it grows exponentially with the number of considered tables.

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Abstract

Regional flood frequency analysis is considered to be an important and popular method for estimating different hydrological variables at ungauged sites. The estimation of the index flood is the essential problem when this method is applied. The objective of the study is a comparison of the estimation of the mean annual flood (or index flood) by using two approaches based on the ‘so-called’ index flood method and top-kriging. The concept behind these methods permits estimating the mean annual flood at ungauged locations using information taken from gauged sites located within the same homogeneous pooling groups. The study area comprises 104 gauging stations on the whole territory of Slovakia. The observation period of the annual maximum discharges of the selected stations was from 1961-2010. The identification of the homogeneous pooling group was performed using a non-hierarchical k-means clustering algorithm. The optimal number of clusters is determined by the Silhouette method. As a result, eight homogeneous pooling group clusters were identified. Finally, the results of the estimated mean annual floods using the index flood method and top-kriging were compared with the observed data. Top-kriging provided better results than the classical index flood method for estimating the mean annual flood at ungauged sites.

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