Tento článek se pokouší vysvětlit schema ve tvaru U v míře návratu migrantů ve vztahu k dosaženému vzdělání. Vytváříme OLG model na dvě období, kde jsou rozhodnutí emigrovat a navrátit se udělána činiteli, kteří jsou heterogenní z pohledu dosaženého vzdělání. Imigrační politika je brána v potaz jako další determinanta migračního rozhodnutí. Model předpovídá, že kombinace dvou sil - relativní návratnost vzdělávání a nejisté příležitosti pro přizpůsobení statusu - vede ke kladným podmínkám k tomu, aby migranti se středoškolským vzděláním zůstali v zahraničí natrvalo., Renata Ivanova, Byeongju Jeong ; editor: Michal Kejak., and born digital
In this paper we present the first insight about the impact of the COVID epidemic on the pri-mary housing market in Poland, with a focus on Warsaw which is the largest market. We ex-plain the structural features that allowed the market to return to pre-shock levels after the pandemic shock. Contrary, after the 2007-2008 global financial crisis the negative consequences lasted for several years. This time a sharp monetary policy and fiscal intervention was carried out. Moreover, the developer sector is much more mature, has expanded its production capaci-ties. We show empirically that the monopolistic competition of developers allowed them to restrict excessive demand that was observed before the COVID broke out. In this way they were able to increase prices despite the economic problems. Another important structural change was the increased housing demand, mainly for investment housing, which was fi-nanced predominantly with cash and contributed to the development of the rental market. We approximate the investment demand, which was generated by private households that pur-chased flats for rental, with the help of a simple demand and supply model.
The coffee plant is native to shaded environments and its seedlings are often produced in shaded nurseries. However, some nursery managers, in an effort to improve the acclimation of seedlings to field conditions after transplantation, produce seedlings in full sun exposure. In this study, the morphological and physiological parameters of arabica coffee (Coffea arabica) seedlings produced in full sun (T1) and in shade (T2) were examined. The biomass accumulation and relative growth rate of T1 and T2 seedlings were similar. The T1 seedlings had less biomass allocation to shoots, a lower leaf mass ratio and a lower leaf area ratio; however, they had a greater net assimilation rate (rate of increase in plant mass per unit leaf area), which was associated with a greater net photosynthetic rate. There were no alterations in the concentrations of total chlorophylls or in the chlorophyll a/b ratio when comparing T1 and T2 seedlings. No indications of photoinhibition or photooxidative damage were observed in the T1 plants, which were shown to have a more robust antioxidant system than the T2 plants. Seedlings transferred from shade to full sun (T3) were not capable of utilising the incident extra light to fix CO2. These seedlings showed a remarkable nocturnal retention of zeaxanthin and a significantly increased deepoxidation state of the xanthophyll cycle, even at predawn, but the activity of antioxidant enzymes was lower than in the T1 and T2 plants. Despite the acclimation capacity of T3 seedlings to the new light environment, they exhibited chronic photoinhibition and considerable photooxidative damage throughout the seven days following the transfer to full sun exposure. We further discuss the practical implications of producing coffee seedlings in full sunlight and under shade. and G. A. B. K. Moraes ... [et al.].
In this paper, a theoretical approach of a wideband preamplifier using a high-end operation amplifier OPA847 will be presented. This device is designed to be used for a low noise, wide band measuring. The level of optimization is based on a noise model for the electrical part of the receiver. During the process of amplifier designing, all the noise components have been investigated separately, using operational amplifiers models. Although this preamplifier was designed to serve for the purposes of flame sensors evaluate, it can be also used to other purposes requiring wide band amplifier with low noise, under only a minimal modification. and V tomto příspěvku bych rád přiblížil teoretický postup návrhu
širokopásmového předzesilovače, využívajícího moderní integrovaný
předzesilovač OPA847, který je určen pro nízkošumová
měření. Stupeň optimalizace je založen na šumovém modelu pro
elektrickou část přijímače. Během návrhu zesilovače byla každá
šumová složka zkoumána zvlášť s využitím modelu operačního
zesilovače. Přestože byl tento předzesilovač navržen pro účely
měření detektorů plamene. Může být s výhodou využit všude jinde,
kde je vyžadován širokopásmový, nízkošumový předzesilovač a to
jen s minimálními úpravami.
Three vernacular texts from late-13th-century Bohemia, in Middle High German and Old Czech, integrate motifs associated with the Holy Land, pilgrimage and the crusades. The romance Wilhalm von Wenden manifests the late Přemyslids’ royal ideology by portraying an independent, pious ruler who derives authority from Jerusalem. The Alexandreis explores the psychology of a military expedition to provide ground for moral reflection and draws on cartography to exploit the symbolism of Jerusalem’s geographic centrality. The crusade-related details in the Legend of Saint James the Less attest to an informed use of intertextual practices.