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The aim of the work was the chromatographic separation of salicylic acid and their derivatives, i.e., acetylsalicylic acid, salicylanilide, salicylaldehyde, salicylamide, methyl salicylate, phenyl salicylate, 2,5-dihydroxybenzoic acid, salicylhydroxamic acid, 3,5-dinitrosalicylic acid, 3-aminosalicylic acid, 4-aminosalicylic acid, and 5-aminosalicylic acid by use of adsorption thin-layer chromatography (normal-phase thin-layer chromatography [NPTLC]) and partition thin-layer chromatography (reversed-phase thin-layer chromatography/high-performance thin-layer chromatography [RP-TLC/HPTLC]). Three qualitatively and quantitatively different mobile phases were used for the separation of salicylic acid and its derivatives. Cluster analysis (single linkage method, Euclidean distance) allowed the evaluation of the suitability of the chromatographic conditions used to separate the pairs of tested compounds. The cluster analysis data indicate that the composition of the mobile phase is fundamental in the process of separation of the analyzed compounds by use of NP-TLC. The best separation of the studied substances was observed in the case of mobile phase n-hexane—diethyl ether—acetic acid (80%) in different volume ratios. The similarity analysis of the results obtained by use of RP-TLC/HPTLC revealed that the type of chromatographic plates influences significantly the quality of separation of the tested compounds. The best conditions for the separation by RP-TLC were obtained on silica gel RP-18 F254 plates. The present study indicates that the cluster analysis represents a simple-to-use and powerful chemometric tool in the prediction of TLC separation of medically important salicylic acid derivatives under various chromatographic conditions. It can be helpful in the quality control of multicomponent synthetic preparations containing these compounds or in the chemical standardization of plant products consisting of salicylic acid and related compounds.

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Abstract  

This paper deals with two document-document similarity approaches in the context of science mapping: bibliographic coupling and a text approach based on the number of common abstract stems. We used 43 articles, published in the journal Information Retrieval, as test articles. An information retrieval expert performed a classification of these articles. We used the cosine measure for normalization, and the complete linkage method was used for clustering the articles. A number of articles pairs were ranked (1) according to descending normalized coupling strength, and (2) according to descending normalized frequency of common abstract stems. The degree of agreement between the two obtained rankings was low, as measured by Kendall’s tau. The agreement between the two cluster solutions, one for each approach, was fairly low, according to the adjusted Rand index. However, there were examples of perfect agreement between the coupling solution and the stems solution. The classification generated by the expert contained larger groups compared to the coupling and stems solutions, and the agreement between the two solutions and the classification was not high. According to the adjusted Rand index, though, the stems solution was a better approximation of the classification than the coupling solution. With respect to cluster quality, the overall Silhouette value was slightly higher for the stems solution. Examples of homogeneous cluster structures, as well as negative Silhouette values, were found with regard to both solutions. The expert classification indicates that the field of information retrieval, as represented by one volume of articles published in Information Retrieval, is fairly heterogeneous regarding research themes, since the classification is associated with 15 themes. The complete linkage method, in combination with the upper tail rule, gave rise to a fairly good approximation of the classification with respect to the number of identified groups, especially in case of the stems approach.

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Franciaország és Magyarország meglehetősen eltérő fejlődési pályát járt be az elmúlt 150 évben, mindkét országban közös azonban az örökölt monocentrikus térstruktúra. A gazdasági és politikai centralizációs törekvések a XVIII–XIX. századra vezethetőek vissza, a monocentrikus térszerkezetből származó hátrányok felismerése és ellenpólusok kijelölése az 1950-es, 1960-as évekre, a fejlesztéspolitika eredményeinek értékelése pedig a XX. század végére. Hogy sikerült-e változást elérni, jól tükrözi, hogy a XXI. század elején megfogalmazott fejlesztéspolitikai koncepciók célja továbbra is a monocentrikus térszerkezet oldása, Franciaországban Párizs, Magyarországon pedig Budapest dominanciájának csökkentése. Az értekezés célja Franciaország és Magyarország fejlesztéspolitikájának párhuzamba állítása, a különbségek és a hasonlóságok elemzése. Ennek során a következők kerülnek bemutatatásra: – a monocentrikus térszerkezet kialakulásának történelmi okai, – a kiegyenlített területi fejlődés érdekében elméletben és a gyakorlatban alkalmazott növekedési pólus koncepciók, – a fejlesztéspolitika jövőképe.

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Abstract  

Biliverdin is a useful component in various aspects of biochemistry and biosynthesis, but its synthetic preparation is often long-winded. Micro-production (and subsequent isolation) by solar photolysis and gamma radiolysis of bilirubin provides rapid in vitro generation. Both methods are competitive, and this article discusses their merits and limitations for application in biosynthetic research. The investigation assumed a comparative study to evaluate the relative potential of the photolytic and radiolytic phenomena in this respect. The calculated rate of incident energy in the case of solar photolysis was roughly30.4.10-2 W, and about 5.70.10-4 W during gamma-irradiation (from a 137Cs source). In both cases the bilirubin (40 µM) degradation was pronounced in the initial few minutes of exposure, producing respective depletion rates of approximately 6.8 µM/min and 2.4 µM/min. Overall, both applications showed declining bilirubin concentrations close to 90%, after about 30 minutes. However, the corresponding production of biliverdin was higher by about 50% in the photolytic application. To account for heat-up effects in the photolytic application, thermal effects were studied up to 65 °C, and it was found that, as a result of this, a reduction in bilirubin concentration of about 40% was encountered. The species of interest were monitored spectrophotometrically, and the composite results showed that regulated production of biliverdin is possible under certain conditions.

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Abstract  

Let

\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $${\mathcal{G}}$$ \end{document}
be a group of affine transformations of the plane that contains a strict contraction and all translations. It is shown that any two topological discs
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$D,E \subseteq {\mathbb{R}}^2$$ \end{document}
are congruent dissection with respect to
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $${\mathcal{G}}$$ \end{document}
such that only three topological discs are used as pieces of dissection. Two pieces of dissection do not suffice in general even if
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\mathcal{G}$$ \end{document}
consists of all affine transformations.

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Orvosi Hetilap
Authors: Helga Judit Feith, Zsuzsanna Soósné Kiss, Ágnes Kovácsné Tóth, and Péter Balázs

Ismereteink szerint ez idáig nem történt olyan átfogó vizsgálat Magyarországon, amely egészségügyi felsőoktatásban tanuló hallgatók szociokulturális hátterét vizsgálta volna. Célkitűzés: Keresztmetszeti kutatásunk fő célkitűzése az volt, hogy megismerjük és elemezzük a leendő orvosnők, diplomás ápolónők és védőnők társadalmi hátterében megmutatkozó különbségeket. Módszer: Jelen kutatásunk orvostanhallgató-nők, valamint egészségügyi főiskolai karon tanuló hallgatónők között készült, a Semmelweis Egyetemen. Összesen 295 hallgatónőt vontunk be a kutatásba, értékelhető választ adott 68,08% ( n = 201). Az eredményeket az SPSS programcsomag segítségével elemeztük, leíró statisztikai megközelítésben. Eredmények: A felmérésben részt vevő hallgatónők számos szociodemográfiai jellemzőjében meghatározó különbséget tapasztaltunk. Az orvostanhallgató-nők nagyobb hányada diplomás szülők gyermeke, ugyanakkor a főiskolai szintű képzésben részt vevő hallgatónők esetében ennek jóval kisebb az esélye. Nem találtunk ugyan statisztikailag alátámasztható különbséget a három hallgatói csoport családi állapotában, de megállapítható, hogy kevesebb diplomásápoló-hallgatónő volt férjezett, illetve élt élettársi kapcsolatban. Következtetések: A főiskolai hallgatónők, valamint az orvostanhallgatók szociokulturális hátterében megmutatkozó különbségek, az ebből következő társadalmi hátrányok nagyobb mértékben sújtják az ápoló- és védőnőhallgatókat, mint az orvostanhallgató-nőket.

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Acta Physiologica Hungarica
Authors: R Bravo Santos, J Delgado, J Cubero, L Franco, S Ruiz-Moyano, M Mesa, AB Rodríguez, C Uguz, and C Barriga

The objective of the present study was to compare differences between elderly rats and young obesity-induced rats in their activity/inactivity circadian rhythm. The investigation was motivated by the differences reported previously for the circadian rhythms of both obese and elderly humans (and other animals), and those of healthy, young or mature individuals. Three groups of rats were formed: a young control group which was fed a standard chow for rodents; a young obesity-induced group which was fed a high-fat diet for four months; and an elderly control group with rats aged 2.5 years that was fed a standard chow for rodents. Activity/inactivity data were registered through actimetry using infrared actimeter systems in each cage to detect activity. Data were logged on a computer and chronobiological analysis were performed. The results showed diurnal activity (sleep time), nocturnal activity (awake time), amplitude, acrophase, and interdaily stability to be similar between the young obesity-induced group and the elderly control group, but different in the young control group. We have concluded that obesity leads to a chronodisruption status in the body similar to the circadian rhythm degradation observed in the elderly.

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At the onset of the mass protests in 2010–2011, many politicians and experts suggested that Arab countries could learn from the experiences of the post-communist transition of the early 1990s. However, the geopolitical, historical, and socio-economic context of the Arab transition was different in many respects from that of the former Soviet bloc countries 20 years earlier. These differences became even more obvious five years later, in early 2016, when most Arab transition attempts ended either in a new wave of authoritarianism, or protracted bloody conflicts. Nonetheless, there are some common lessons to be learnt from the history of both transitions. They concern interrelations between the political and economic transition, the role of institutional checks and balances and the rule of law, the speed of reforms, the dangers of ethnic and sectarian conflicts, and the role of external support.

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