Centurial Changes in the Depth Conditions of a Regulated River: Case Study of the Lower Tisza River, Hungary

The Tisza River is the largest tributary of the Danube in Central Europe, and has been subjected to various human interventions including cutoffs to increase the slope, construction of levees to restrict the floodplain, and construction of groynes and revetments to stabilize the channel. These interventions have altered the natural morphological evolution of the river. The aim of the study is to assess the impacts of these engineering works, employing hydrological surveys of 36 cross sections (VO) of the Lower Tisza River for the years of 1891, 1931, 1961, 1976 and 1999. The changes in mean depth and thalweg depth were studied in detail comparing three reaches of the studied section. In general, the thalweg incised during the studied period (1891-1931: 3 cm/y; 1931-1961: 1.3 cm/y and 1976-1999: 2.3 cm/y), except from 1961-1976 which was characterized by aggradation (2 cm/y). The mean depth increased, referring to an overall deepening of the river during the whole period (1891-1931: 1.4 cm/y; 1931-1961: 1.2 cm/y; 1961-1976: 0.6 cm/y and 1976-1999: 1.6 cm/y). The thalweg shifted more in the upper reach showing less stabile channel, while the middle and lower reaches had more stable thalweg. Although the cross-sections subjected to various human interventions experienced considerable incision in the short-term, the cross-sections free from direct human impact experienced the largest incision from 1891-1999, especially along the meandering sections

Delayed feedback induced multirhythmicity in the oscillatory electrodissolution of copper

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Évaluation du potentiel récréatif des environs d’une ville de la Grande Plaine hongroise : Debrecen

Avec le développement de la vie citadine moderne, les besoins récréatifs de la population augmentent à un rythme accéléré. Pour les satisfaire, l’environnement naturel joue un rôle croissant, justement à cause du caractère urbain du mode de vie. Les villes entourées de reliefs accidentés, de nombreux plans d’eau et d’une végétation abondante sont favorisées dans ce domaine. De ce point de vue, les villes de la Grande Plaine hongroise, au relief monotone et à l’aridité prononcée, ne sont pas dans une situation avantageuse. Debrecen, devenue la deuxième ville du pays au cours de la dernière décennie, dispose ainsi de possibilités plus restreintes que la moyenne. L’étude recense les dispositions naturelles en matière de loisirs des environs de cette ville, située au contact de deux parties différentes de la plaine. Elle démontre d’abord la dualité géomorphologique des alentours de la ville (à l’est, un espace constitué de dunes de sables éoliens sous couvert forestier dominant — le Nyírség ; à l’ouest une dorsale de lœss — Hajdúhát), puis met l’accent sur les conséquences négatives de la pauvreté en eaux superficielles de la ville et de ses périphéries. Elle s’attache ensuite aux tentatives et projets de lutter contre l’aridité en introduisant l’eau du Grand Canal de l’Est sur des espaces au potentiel récréatif certain, avant d’analyser l’importance récréative et le dépérissement de la Grande Forêt du nord de la ville. Enfin, elle examine le déclin des étangs de loisirs artificiels de l’Erdıspuszta, crées dans les dunes du Nyírség, avant d’évoquer, dans la dernière partie, le modeste potentiel récréatif de la dorsale de lœss de l’ouest de la ville. En conclusion, les auteurs soulignent que le manque d’eau nécessaire au développement des loisirs dans les environs de la ville pourrait être résolu en dérivant une partie de l’eau du Grand Canal de l’Est destinée actuellement à la ville seule.With the spread of modern urban life, the recreational demands of the population are growing at an accelerating rate. In satisfying these demands, the natural environment assumes an ever-increasing role, due to the character of urban life. Cities surrounded by hilly relief, abundant vegetation and rich natural waters are therefore advantaged. The cities of the Great Hungarian Plain, with its monotonous relief and pronounced aridity, are not favourably placed. The opportunities for Debrecen, which has grown into the second largest city in the country in the last decade, are even more restricted. This study reviews the natural resources of this city, situated between two different parts of the plain, with respect to leisure activities. It describes the dual geomorphological character of the city’s environs (to the east, an area of mostly forested sand dunes — Nyírség ; to the west a loess plain — Hajdúhát), laying emphasis on the negative consequences of a shortage of surface water in the city and its outskirts. It presents and evaluates efforts to counter the aridity by introducing the water of the East Main Canal into the areas with definite recreational potential, before analysing the recreational importance and decay of the Great Forest in the northern part of the city. Lastly, the study examines the decline of the artificial leisure lakes of the Erdıspuszta, created in the dunes of the Nyírség, before mentioning, in the last part, the modest recreational potential of the loess plain west of the city. In conclusion, the authors emphasise that the lack of necessary water for the development of recreation in the environs of the city can be resolved by diverting part of the water of the East Main Canal presently destined for the city itself.Mit der Entwicklung des modern städtischen Lebens vergrößern sich die Erholungsbedürfnisse der Bevölkerung in beschleunigtem Rhythmus. Um sie zu befriedigen, spielt die natürliche Umwelt eine zunehmende Rolle, gerade wegen der städtischen Lebensweise. Die Städte mit reliefreicher Umgebung, zahlreichen Wasserflächen und reicher Vegetation sind in dieser Hinsicht begünstigt. Diesbezüglich sind die Städte der Grossen Ebene Ungarns mit monotonem Relief und ausgeprägter Aridität in keiner vorteilhaften Lage. Debrecen, im letzten Jahrzehnt zur zweiten Stadt des Landes geworden, verfügt so über beschränktere Möglichkeiten als der Durchschnitt des Städte. Die Studie erfasst die natürlichen Voraussetzungen für die Freizeit im Umland dieser Stadt, die am Kontakt zweier verschiedener Teile der Ebene liegt. Die Arbeit zeigt zuerst die Dualität der Umgebung der Stadt auf (im Osten ein Raum mit äolischen Sanddünen unter vorherrschender Walbedeckung — der Nyírség ; im Westen ein Lössrücken — Hajdúhát) und setzt dann den Akzent auf die negativen Folgen der Oberflächigen Wasserarmut der Stadt und ihres Umlands. Die Studie widmet sich dann den Versuchen und Projekten zur Bekämpfung der Aridität durch Einleiten des Wassers des Grossen Ostkanals auf Flächen mit sicherem Erholungspotential und analysiert dann den Erholungswert und das Waldsterben des Großen Waldes in Norden der Stadt. Schließlich wird er Verfall der künstlichen Freizeitseen von Erdıspuszta, die in den Dünen von Nyírség angelegt wurden, überprüft und im letzten Teil auf das bescheidene Erholungspotential des Lössrückens im Westen der Stadt hingewiesen. Zusammenfassend unterstreichen die Autoren, dass der Mangel des für die Entwicklung der Freizeit im umland des Stadt notwendigen Wassers behoben werden könnte, wenn ein Teil des Wassers des Grossen Ostkanals, das derzeit nur für die Stadt bestimmt ist, abgeleitet würde

The Effects of Environment and Physiological Cyclicity on the Immune System of Viperinae

One of the important aspects of species' survival is connected with global climate changes, which also conditions the epidemiology of infectious diseases. Poikilotherms are exposed, as other species, to climatic influence, especially due to their physiological peculiarities such as important stages of their life cycle: hibernation, shedding, and active phase. The immune system serves as an accurate indicator of the health status and stress levels in these species. This study aimed to monitor the changes of innate (leukocyte subpopulations and total immune globulins) and adaptive immunity (in vitro leukocyte blast transformation) of two viper species, V. berus berus and V. ammodytes ammodytes, endemic in Europe and spread in different regions of Romania during their three major life cycles, hibernation, shedding, and active phase. The results indicated that seasonal variance and cycle rather than species and regional distribution influence the functionality of the immune system

Emerging novel porcine parvoviruses in Europe: origin, evolution, phylodynamics and phylogeography

To elucidate the spatiotemporal phylodynamics, dispersion and evolutionary processes underlying the emergence of novel porcine parvovirus 2 (PPV2), PPV3 and PPV4 species, we analysed all available complete capsid genes, together with ours, obtained in Europe. Bayesian phylogeography indicates that Romania (PPV2 and PPV4) and Croatia (PPV3) are the most likely ancestral areas from which PPVs have subsequently spread to other European countries and regions. The timescale of our reconstruction supported a relatively recent history of the currently circulating novel PPV species (1920s to 1980s) in the domestic or sylvatic host. While PPV2 strains exhibited a large genetic exchange characterized by significant recombination and gene flow between distinct regions and hosts, PPV3 and PPV4 showed a diversification reflected by the accumulation of geographically structured polymorphisms. The RNA-like evolutionary rates detected inter- and intrahost recombination and the positive selection sites provided evidence that the PPV2-4 capsid gene plays a prominent role in host adaptation

BDNF Val66Met polymorphism and stressful life events in melancholic childhood-onset depression

INTRODUCTION: Brain-derived neurotrophic factor (BDNF) polymorphisms have been examined for their contribution toward depression with equivocal results. More homogeneous phenotypes might be used to improve our understanding of genetic liability to depression. The aim of our study was to (a) test for an association between the BDNF Val66Met polymorphism and childhood-onset melancholic depression and (b) to examine the interactive effects of stressful life events (SLE) and the Val66Met polymorphism on the risk of childhood-onset melancholic depression. MATERIALS AND METHODS: A total of 583 depressed probands were involved in this study (162 of the melancholic subtype). Diagnoses were derived through the Interview Schedule for Children and Adolescents - Diagnostic Version and life event data were collected using an Intake General Information Sheet. RESULTS: Overall, 27.8% of the participants fulfilled the criteria for melancholy. In the melancholic group, the proportion of females was higher (53.1%), although there were more males in the overall depressed sample. We detected no significant differences in genotype or allele frequency between the melancholic and the nonmelancholic depressed group. The BDNF Val66Met polymorphism and SLE interaction was not significantly associated with the melancholy outcome. CONCLUSION: In our study, females were more prone to developing the early-onset melancholic phenotype. To our knowledge, this is the first study to investigate the differentiating effect of the genotype and the GxE interaction on the melancholic phenotype in a large sample of depressed young patients. We did not find an association between the melancholic subtype of major depression and the BDNF genotype and SLE interaction in this sample, which is representative of the Hungarian clinic-referred population of depressed youths