101 research outputs found
Ecological indicator based comparative study of tree of heaven (Ailanthus altissima) stands’ herb layer
Tree of heaven (
Ailanthus altissima
) is one of the most dangerous and spread woody-stemmed invasive
plant species in Hungary. By its nature it transforms its environment and reduces the biodiversity of the area.
These processes can be observed studying species composition of habitats heavily infected by tree of heaven.
In our research we studied the herb layered species composition of plant communities that were tree of heaven
dominated in canopy in Fót, Gyermely, Makád and Tököl. After determining the species associated Borhidi’s
relative ecological indicators and Raunkiaer’s life-forms have been applied and analysed for the distribution of the
categories. Accordingly most of the species occurring in the herb layer of studied areas were herbaceous. In these
stands disturbance tolerant species, generalists and weed species are common, but more, aggressive competitors
also appear. These species are indicators of degraded and disturbed habitats however there was also a protected
area (FĂłti-SomlyĂł). Summing the indicators of relative temperature figures it can be stated that most of the species
indicated the relative temperature demand of submontane broad-leaved forests. According to wetness requirement
of the species, studied tree of heaven stands were semihumid. Looking at the relative nitrogen figures, species
show a wide variety, but most of them indicate a moderately nutrient-rich, or richer habitat. On herb layer halflight
plant species prevailed which indicates that these tree of heaven infected stands were less closed, allowing more
light to come down to the herb layer. In continentality suboceanic and intermediate types dominated. The majority
of the species is halophob, that does not tolerate the salty environment
ElfelejtjĂĽk az irreleváns informáciĂłkat? - epizodikus emlĂ©kezeti elĹ‘hĂvás vizsgálata kĂ©nyszerbetegsĂ©gben
Az obszesszĂv-kompulzĂv zavar (OCD, kĂ©nyszerbetegsĂ©g) egy sĂşlyos neuropszichiátriai kĂłrkĂ©p, melyet a nemkĂvánatos betörĹ‘ gondolatok (obszessziĂłk) Ă©s/vagy az ismĂ©tlĹ‘dĹ‘ kompulzĂv cselekvĂ©sek, mentális rituálĂ©k (kompulziĂłk) jellemeznek (Amerikai Pszichiátriai Társaság, 1994). A klinikai tĂĽnetek egyik lĂ©nyeges kognitĂv háttĂ©rfaktorakĂ©nt legtöbb szerzĹ‘ a vĂ©grehajtĂł rendszer diszfunkciĂłját emeli ki (Kuelz Ă©s mtsai., 2004; Abramovitch Ă©s mtsai., 2013), ami szorosan kapcsolĂłdik a számos vizsgálat által kimutatott orbitofrontális Ă©s dorsalis anterior cinguláris deficitekhez OCD-ben (Milad Ă©s Rauch, 2012). Ugyanakkor Chamberlain Ă©s mtsai., (2005) szerint a vĂ©grehajtĂł rendszer nem minden aspektusa sĂ©rĂĽlt OCD-ben. A klinikai tĂĽnetek Ă©s a fĹ‘ kognitĂv deficitek - mint, a prepotens válasz gátlása, a szett váltás Ă©s a hatĂ©kony szervezĂ©si stratĂ©gia használat az emlĂ©kezeti prĂłbákban – megmagyarázhatĂłak a kognitĂv Ă©s a viselkedĂ©si gátlás sĂ©rĂĽlĂ©sĂ©vel. ElĹ‘zetes kutatásokbĂłl tudjuk, hogy az emlĂ©kek elĹ‘hĂvása a vĂ©grehajtĂł rendszer működĂ©sĂ©t involválja, amely a cĂ©l emlĂ©kek aktiválása mellett csökkenti a versengĹ‘ emlĂ©knyomok elĂ©rhetĹ‘sĂ©gĂ©t. Ezt a hatást nevezzĂĽk elĹ‘hĂvás kiváltotta felejtĂ©snek (retrieval induced forgetting – RIF), amit leggyakrabban a szelektĂv gyakorlási paradigmával vizsgáltak. Az emlĂ©kezeti patolĂłgiák megĂ©rtĂ©se szempontjábĂłl alapvetĹ‘ tudományos kĂ©rdĂ©s, hogy vajon a RIF hatás a versengĂ©s feloldásában szerepet játszĂł gátlási folyamatoknak vagy csupán az elĹ‘hĂvott emlĂ©kek megerĹ‘södĂ©sĂ©nek Ă©s interferenciájának tulajdonĂthatĂł-e. CĂ©lunk, hogy egy klinikai vizsgálat keretĂ©ben bizonyĂtĂ©kokat szerezzĂĽnk a vĂ©grehajtĂł kontroll folyamatok szerepĂ©rĹ‘l a RIF hatás elĹ‘idĂ©zĂ©sĂ©ben. Mivel korábbi adatok szerint a RIF hatás összefĂĽgg a munkamemĂłria kapacitással Ă©s a szorongás szintjĂ©vel, ezĂ©rt vizsgálatunkban ezeket a változĂłkat is mĂ©rtĂĽk. A vizsgálatban 25 OCD-vel diagnosztizált szemĂ©ly, illetve 25, kor Ă©s iskolázottság mentĂ©n illesztett, kontroll szemĂ©ly vett rĂ©szt. Egy mĂłdosĂtott szelektĂv gyakorlási paradigmát használtunk, mely alkalmas volt nem csak a találatok/hibázások, hanem az adott válaszok reakciĂłidejĂ©nek a rögzĂtĂ©sĂ©re is. EredmĂ©nyeink azt mutatják, hogy az emlĂ©kezeti elĹ‘hĂvás gyakorlása mindkĂ©t csoportban a gyakorolt emlĂ©kek jobb felidĂ©zĂ©sĂ©hez vezetett, azonban csak a kontroll csoportban vezetett RIF-hez, az OCD csoportban nem. Nem találtunk összefĂĽggĂ©st a RIF hatás Ă©s az állapot, vonás szorongás mĂ©rtĂ©ke között a (STAI) illetve a RIF hatás Ă©s a munka- (N-vissza feladatok), rövid távĂş memĂłria kapacitás (Számterjedelem ElĹ‘re feladat) között. ValĂłszĂnűleg a RIF hatás hiánya az OCD-ben megfigyelhetĹ‘ konfliktus detektálĂł folyamatok zavarával magyarázhatĂł, melynek hátterĂ©ben az anterior cinguláris Ă©s a prefrontális kĂ©reg fokozott aktivitása valĂłszĂnűsĂthetĹ‘.
Kulcsszavak: emlĂ©kezet, elĹ‘hĂvás kiváltotta felejtĂ©s, obszesszĂv kompulzĂv zavar, vĂ©grehajtĂł kontrol
Obsessed not to forget: lack of retrieval induced forgetting effect in obsessive compulsive disorder (OCD)
Study objectives: To investigate the role of executive functions in resolving memory interference in a clinical sample of patients with obsessive-compulsive disorder (OCD).
Method: Retrieval of memories has been shown to involve an executive mechanism that diminishes the accessibility of rival memory traces, leading to retrieval induced forgetting (RIF). These executive control processes might suppress unwanted thoughts and irrelevant memories during competitive retrieval. We hypothesized that OCD patients manifest reduced RIF compared to the matched healthy controls due to impaired executive functions that are supposed to resolve interference during competitive retrieval.
We assessed RIF with the retrieval practice paradigm among twenty five OCD patients and twenty five healthy controls matched for age and education. In contrast to most previous clinical studies of RIF, we used a method where the observed RIF effect can only be explained by inhibitory processes, and not for instance by interference. In addition to recall accuracies, we focused on differences in recall latencies as a measure of RIF to ensure that any effect that decreases accessibility of memories due to competitive retrieval would be detected. We controlled for working memory (n-back Task), symptom severity (Yale- Brown Obsessive Compulsive Scale, Y-BOCS) and trait and state anxiety (Spielberger State and Trait Anxiety Inventory, STAI).
Results: Retrieval of target memories led to enhancement of target memory recall in both groups, but suppression of related memories (RIF) occurred only among controls. This finding was not due to different levels of working memory, symptom severity and anxiety. Learning curves during the retrieval practice phase were similar in the two groups. Therefore the lack of RIF among OCD patients was not related to overall learning or recall performance.
Conclusions: Suppression of irrelevant, interfering memories during competitive recall is impaired in OCD.
Educational objectives: To promote cognitive experimental approaches to OCD research and therapy
Examination the health state with instrumental measurements and the diversity of sessile oak stands in Zemplén mountains
Researching the naturalness of forests has been becoming more and more pronounced in Hungary, since the forest’s ecosystems are also concerned by the biosphere crisis, that is a global degradation of the biotic environment. This deterioration could be observed not only through the decrease of the extention of the forests, but also through the altering of their structures. FAKOPP 3D Acoustic Tomograph have been used and coenological surveys have been carried out in 3 different layers. The examinations have been accomplished in sessile oak stands of the Zemplén Mountains, within 5 different age groups. According to the results of the instrumental measurements – except the youngest age group – the highest value of the rottenness is located in the closest layer to the topsoil, then upwards on the trunk it shows decreasing tendency. Among the stands the 80 years old age group proved to be the healthiest, while the 20 years old group had the worst values. Based on the Shannon and Simpson diversity, the most diverse age group in the ground layer is the 60 years old group, while in the canopy is the 80 years old group. The rottenness measured in the younger stands concerned the higher parts of the trunks and it has presumably evolved because of the frost cracks. The diversity values of the shrub and the ground layer followed the same tendency
EgyensĂşlyi fázisdiagrammok számĂtása ESTPHAD mĂłdszerrel = Calculation of Equilibrium Phase Diagrams by ESTPHAD method
Az egyensĂşlyi fázisdiagramok igen jelentĹ‘s rĂ©sze csak grafikusan ismert, vagy - egy csekĂ©ly hányaduk -komplikált, igen hosszĂş CPU idĹ‘t lekötĹ‘ eljárással számĂthatĂł ki. Ez a felismerĂ©s vezetett az ESTPHAD mĂłdszer Ă©s szoftver kidolgozásához. A mĂłdszer alapja az átalakulási hĹ‘mĂ©rsĂ©kletet leĂrĂł -termodinamikai összefĂĽggĂ©sekbĹ‘l levezetett- egyenletek, melyekkel kiszámĂthatĂłk az átalakulások kezdĹ‘ Ă©s befejezĹ‘ hĹ‘mĂ©rsĂ©kletei. A rendszer hierarhikus, azaz a többalkotĂłs rendszerek egyenletei tartalmazzák az alacsonyabb rendű rendszerek állandĂłit. Az állandĂłk mĂ©rt, grafikusan ismert vagy valamely termodinamikai számĂtásbĂłl kapott adatokbĂłl regressziĂłval határozhatĂłk meg. A munka során 16 kĂ©talkotĂłs vas, 12 kĂ©talkotĂłs alumĂnium alapĂş, számos rĂ©z Ă©s nemesfĂ©m alapĂş kĂ©talkotĂłs rendszer vonalainak adatait dolgoztuk fel egĂ©szben vagy rĂ©szben. A kĂ©talkotĂłs alumĂnium alapĂş ötvözetek adatait felhasználva 4 háromalkotĂłs egyensĂşlyi fázisdiagram alumĂnium sarkának likvidusz Ă©s szolidusz felĂĽleteinek az egyenleteit is meghatároztuk. Feldolgoztuk 6 binĂ©r, 4 ternĂ©r Ă©s egy kvaternĂ©r oxid rendszert is. A rendszer egyszerű felhasználása Ă©rdekĂ©ben egy szabadon felhasználhatĂł szoftvert dolgoztunk ki. A szoftver alkalmas az adatbázisban valĂł keresĂ©sre, valamint lehetĹ‘sĂ©g nyĂlik olyan szoftver rĂ©szek letöltĂ©sĂ©re, amelyeket a szimuláciĂłs programba Ă©pĂtve bárki ki tudja számĂtani az egyensĂşlyi fázisdiagramok adatait. A szoftver Ă©s az adatbázis a www.matsci.uni-miskolc.hu/estphad honlaprĂłl szabadon letölthetĹ‘. | The majority of phase equilibria are known only in graphically presented phase diagrams. Alternatively, it can be computed using a so-called Calphad method. The latter, however, requires long CPU times for the numerical solution. This situation lead us to the idea to develop a new method and a computer code called Estphad. The method is based on thermodynamically derived equations. The Estphad system is hierarchically built. The coefficients of Estphad can be obtained by regression analysis, using measured data, graphical phase diagram, or data obtained by a Calphad computer code. Equilibrium lines of 16 binary iron-, 12 binary aluminum-based, and a number of binary copper-based and precocious metal-based systems have been evaluated. Using the data obtained for the binary aluminum-based alloys, equations, describing the solidus and liquidus surfaces in the Al-corners of four ternary aluminum based systems have been obtained, as well. Additionally six binary, four ternary and one quaternary oxide phase diagrams have been calculated. To ensure a simple and widespread use of our new Estphad system, an open computer code has been developed. The code let anyone to search in the existing database. Also, one can download specific fragments of the code, which can be useful as sub-routines in larger simulation programs to calculate phase equilibrium data. The code and the existing database can be downloaded free of charge from the website www.matsci.uni-miskolc.hu/estphad
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