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Disturbances are important drivers in natural ecosystems, affecting the vegetation structure and functioning. Invasions of exotic plant species are often associated to disturbances in a complex manner, because they depend on the type, intensity, spatial and temporal arrangement of disturbances, and the particular abiotic and biotic context. Field studies that evaluate the dynamics of plant invasions under different disturbance regimes have a great importance for the understanding of the disturbance effects on invasion spread. In this work we evaluated, through a field manipulative experiment, the early colonization and expansion dynamics of an aggressive invader of grasslands, Hieracium pilosella L., under two disturbance types. We used a split-plot experiment by crossing three levels for a local, sporadic, of increasing intensity disturbance [i.e., 1- undisturbed, 2- vegetation mowing, and 3- ploughing], within two levels for an extensive and chronic disturbance (i.e., grazed and ungrazed). In the range of intensities of disturbance evaluated, the intermediate intensity (i.e., mowing) accelerated the colonization when it is grazed and the expansion of H. pilosella in ungrazed condition. In contrast, lower and higher intensity disturbances, such as ungrazed and ploughing treatments decelerated both invasion processes. Changes in resource availability, interspecific competition and particular characteristics of the invader, i.e., high light requirements, prostrate growth and the presence of stolons, could explain these early invasion patterns.

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Abstract  

Although nature looms large throughout Homer’s Odyssey, literary critics have entirely neglected to discuss his construction of the natural world in this foundational Western work. This neglect might be the result of two factors: the blurred line between geographical and fantastical locales in Odysseus’ travels and the blurred line between natural forces and deities. This essay recognizes that Homer not only reconstructs the Mediterranean world in his epic through detailed references to weather, geology, plants, birds, and animals but also that his similes suggest a consciousness of inter-species relationships. Principally, however, this essay argues, as does William Cronon, that “relationships, processes, and systems are as ecological as they are cultural,” and that Odysseus’ response to nature may usefully be understood in relation to three ecocritical models: the anthropocentric or domination model, the stewardship model, and the biomorphic model. His exploitative and aggressive behavior toward the Cyclopes, Circe, and the cattle of the Sun is contrasted with his recognition upon his homecoming of his own animal nature and his appreciation of the agrarian and pastoral life. While the tradition of writing in The Odyssey genre has vigorously continued in Western literature, only recently have contemporary environmental writers moved toward a recognition of the threat of the anthropocentric perspective to the imperative of working toward the stewardship and biomorphic models.

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The task of economics is apparently changing. After confronting the limits to growth, the economic interests, methods and thoughts, even its use of words and concepts are slowly but persistently modified. The discussion of “equilibrium” is replaced by the concern for a “sustainable path”. Instead of finding out how to produce “more” it looks for “better”, “cheaper” and “recyclable” commodities. Labor saving serves by and large the reduction of the working week and transformation of the life-cycle instead of surplus-production. The markets of developed countries are more easily glutted and their recessions deeper. The ever louder and more aggressive marketing attests to all this. It is high time to renew our old ways, to revisit the aged analytical and forecasting models. The renovation of obsolete concepts is rendered necessary to facilitate the introduction of an orderly and planned future of prudence. This investigation focuses less on the seldom, perhaps never occupied point of equilibrium, rather on the behavior and motion of the economic systems in its vicinity.

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Orvosi Hetilap
Authors: Boglárka Brúgós and Margit Zeher

A szisztémás lupus erythematosus poliszisztémás autoimmun betegség, egyik legjelentősebb szervi szövődménye a lupus nephritis. A lupus nephritis időbeni, a krónikus szervi érintettség kialakulását megelőző felismerése, a shubok előrejelzése, a korai agresszív kezelés elkezdése és a terápia sikerességének lemérése kívánatos lenne. Ezért a kutatások egy része intenzíven a legmegfelelőbb, aktivitást előre jelző biomarker megtalálására irányul. Jelen összefoglaló célja a hagyományos szerológiai markerek megbeszélésén túl a legújabb, részben még kísérletes, a klinikai gyakorlatban nem használt, de az SLE, illetve lupus nephritis aktivitását jellemző specifikus biomarkerek bemutatása.

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The glomerular filtration barrier is a highly specialized tri-layer structure with unique functional properties. Podocyte dysfunction and cytoskeletal disorganization leads to disruption of the slit diaphragma, and proteinuria. Inflammatory diseases involving the kidney as well as inherited podocytopathies or diabetic nephropathy cause injury of the podocyte network. Focal segmental glomerulosclerosis (FSGS) is a pathologic entity that is a common cause of nephrotic syndrome with severe proteinuria in both adults and children. Several causative genes have been identified in the pathogenesis of FSGS. Mutations of the transient receptor potential canonical-6 (TRPC6), a non-selective cation channel that is directly activated by diacylglycerol (DAG), cause a particularly aggressive form of FSGS. Angiotensin II, acting through its AT1 receptor, plays a critical role in generation of proteinuria and progression of kidney injury in a number of kidney diseases, including FSGS. Mounting evidence suggest the central role of TRPC6 and perhaps other TRPC channels in the pathogenesis of FSGS as well as of acquired forms of proteinuria such as diabetic nephropathy or hypertension. Identification of signaling pathways downstream of TRPC6 may provide novel targets for the treatment of proteinuria and prevent progression of podocyte injury.

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Abstract  

Two separate studies were undertaken of the personality characteristics associated with research creativity and teaching effectiveness in university psychology professors. In the first study, 52 professors at The University of Western Ontario were evaluated on 29 trait dimensions using four assessment techniques: faculty peer ratings, student ratings, self ratings, and objective questionnaires. A composite criterion of research creativity was generated from publication and citation counts. A composite for teaching effectiveness was created from 5 years of archival data based on formal student evaluations. The personality measures demonstrated considerable convergence across modes of assessment for many traits. In turn, several traits differentiated between most and least creative researchers and most and least effective teachers. A second study, using a self report survey sent to 400 professors in graduate psychology departments at 9 Canadian universities, revealed substantial replications of the findings of Study 1. Limiting ourselves to those personality traits that reliably loaded on Research and Teaching factors in both studies, we may describe the creative researcher as ambitious, enduring, seeking definiteness, dominant, showing leadership, aggressive, independent, non-meek, and non-supportive. The effective teacher is best described as liberal, sociable, showing leadership, extraverted, nonanxious, objective, supporting, non-authoritarian, non-defensive, intelligent, and aesthetically sensitive.

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Cereal Research Communications
Authors: D. Huang, H. Zhang, M. Tar, Y. Zhang, F. Ni, J. Ren, D. Fu, L. Purnhauser, and J. Wu

Stripe or yellow rust (Yr), caused by Puccinia striiformis Westend. (Pst), is one of the most important wheat diseases worldwide. New aggressive Pst races can spread quickly, even between countries and continents. To identify and exploit stripe rust resistance genes, breeders must characterize first the Pst resistance and genotypes of their cultivars. To find new sources of resistances it is important to study how wheat varieties respond to Pst races that predominate in other continents. In this study we evaluated stripe rust resistance in 53 Hungarian winter wheat cultivars in China. Twenty-four cultivars (45.3%) had all stage resistance (ASR) and 1 (1.9%) had adult-plant resistance (APR), based on seedling tests in growth chambers and adult-plant tests in fields. We molecularly genotyped six Yr resistance genes: Yr5, Yr10, Yr15, Yr17, Yr18, and Yr36. Yr18, an APR gene, was present alone in five cultivars, and in ‘GK Kapos’, that also had seedling resistance. The other five Yr genes were absent in all cultivars tested.

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A nyelőcsőrák a hatodik leggyakoribb daganatos halálok, gyakorisága nő. A nyelőcsőrákok 95%-a laphámrák vagy adenocarcinoma. Bár a nyelőcsőlaphámrák és az adenocarcinoma szövettana és előfordulása különböző, számos kockázati tényezőjük (dohányzás, táplálkozási szokások), valamint a daganatkialakulás folyamata hasonló. A nyelőcsőrák több mint 90%-ban előrehaladott állapotban derül ki. A felismerés és a kezelés lehetőségeinek fejlődése ellenére kórjóslata rossz, az ötéves túlélés 10–13%. A kórélettani háttér pontosabb megértése a megelőzést segítheti, részben természetes hatóanyagok, részben nemszteroid gyulladáscsökkentők alkalmazásával.

Open access
Imaging
Authors: Borbála Vattay, Melinda Boussoussou, Sarolta Borzsák, Milán Vecsey-Nagy, Judit Simon, Márton Kolossváry, Béla Merkely, and Bálint Szilveszter

Abstract

Combined anatomical and functional evaluation of coronary artery disease (CAD) using computed tomography (CT) has recently emerged as an accurate, robust and non-invasive tool for the evaluation of ischemic heart disease. Cardiac CT has become a one-stop-shop imaging modality that allows the simultaneous depiction, characterization and quantification of coronary atherosclerosis and the assessment of myocardial ischemia. Advancements in scanner technology (improvements in spatial and temporal resolution, dual-energy imaging, wide detector panels) and the implementation of iterative reconstruction algorithms enables the detection of myocardial ischemia in both qualitative and quantitative fashion using low-dose scanning protocols. The addition of CT perfusion (CTP) to standard coronary CT angiography is a reliable tool to improve diagnostic accuracy. CTP using static first-pass imaging enables qualitative assessment of the myocardial tissue, whereas dynamic perfusion imaging can also provide quantitative information on myocardial blood flow. Myocardial tissue assessment by CTP holds the potential to refine risk in stable chest pain or microvascular dysfunction. CTP can aid the detection of residual ischemia after coronary intervention. Comprehensive evaluation of CAD using CTP might therefore improve the selection of patients for aggressive secondary prevention therapy or coronary revascularization with high diagnostic certainty. In addition, prognostic information provided by perfusion CT imaging could improve patient outcomes by quantifying the ischemic burden of the left ventricle. The current review focuses on the clinical value of myocardial perfusion imaging by CT, current status of CTP imaging and the use of myocardial CTP in various patient populations for the diagnosis of ischemic heart disease.

Open access

Words like aggression, violence, and violent actions usually carry destructive meanings. People tend to forget their constructive culturally determined meanings. In spite of this, it can be argued that aggressive feelings, hatred, anger, verbal aggression, threatening behaviour, assault, inflicting pain, injuring or ritual killing of men, or the fighting of war are all part of our lives as much as feasts and rituals that bind communities together, or the command to love of different religious ideologies. In the 16th century there was a definitive turn in judging the body in public. It meant that public attention gradually turned from the corpse of Christ to the bodies of the thieves. The two thieves were brought down from their crosses, laid out on the dissecting table, or their bodies were torn apart during fights. Evil-doers became part of scientific cognition. The antisocial public enemy became a hero of the community in the popular literature and historic stories. The conserved and stuffed bodies of robbers and killers were displayed in the first museums of the Early Modern Age, as a main attraction. Rebels were cut into pieces as part of a baroque play on the killing floor to display the parts in buildings of the town. The body of the everyday killer became a spectacle, and the interest in the mind of the solitary killer developed medical thinking on the human spirit.

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