Az autonóm terepjáró eszközök = Autonomous Ground Vehicles

A mai korszerű, professzionális hadseregekre jellemző, hogy igyekeznek az emberi erőforrásokat megóvni, szakértelmüket kihasználni lehetőleg anélkül, hogy feleslegesen veszélybe sodornák őket. Ennek egyik megoldása az autonóm terepjáró eszközök alkalmazása. Az autonóm terepjáró eszközök meghatározás, amelyet gyakran fellelhetünk a szakirodalomban, hivatott lefedni mind a valamilyen szintű autonómiával ellátott, mind a vezető nélküli, távvezérelt, automatizált terepjáró eszközöket. Az utóbbi időben egyre több cikk jelenik meg az autonóm járművekkel kapcsolatban, de ezek többsége mindig az adott technológia bemutatásával foglalkozik, mivel többnyire ez érdekli az olvasót. A sok információban viszont az autonómia mint fogalom időnként vegyes képet mutat, ezért fontos, hogy összefoglaljuk az autonómia mint kifejezés elméleti aspektusait

Vertical distribution of soil seed bank and the ecological importance of deeply buried seeds in alkaline grasslands

Background: Soil seed banks play a central role in vegetation dynamics and may be an important source of ecological restoration. However, the vast majority of seed bank studies examined only the uppermost soil layers (0-10 cm); hence, our knowledge on the depth distribution of seed bank and the ecological significance of deeply buried seeds is limited. The aim of our study was to examine the fine-scale vertical distribution of soil seed bank to a depth of 80 cm, which is one of the largest studied depth gradients so far. Our model systems were alkaline grasslands in East-Hungary, characterised by harsh environmental conditions, due to Solonetz soil reference group with Vertic horizon. We asked the following questions: (1) How do the seedling density and species richness of soil seed bank change along a vertical gradient and to what depth can germinable seeds be detected? (2) What is the relationship between the depth distribution of the germinable seeds and the species traits? Methods: In each of the five study sites, four soil cores (4 cm diameter) of 80 cm depth were collected with an auger for soil seed bank analysis. Each sample was divided into sixteen 5-cm segments by depth (320 segments in total). Samples were concentrated by washing over sieves and then germinated in an unheated greenhouse. Soil penetration resistance was measured in situ next to each core location (0-80 cm depth, 1-cm resolution). We tested the number and species richness of seedlings observed in the soil segments (N= 320), using negative binomial generalized linear regression models, in which sampling layer and penetration resistance were the predictor variables. We ran the models for morphological groups (graminoids/forbs), ecological groups (grassland species/weeds) and life-form categories (short-lived/perennial). We also tested whether seed shape index, seed mass, water requirement or salt tolerance of the species influence the vertical distribution of their seed bank. Results: Germinable seed density and species richness in the seed bank decreased with increasing soil depth and penetration resistance. However, we detected nine How germinable seeds of six species even in the deepest soil layer. Forbs, grassland species and short-lived species occurred in large abundance in deep layers, from where graminoids, weeds and perennial species were missing. Round-shaped seeds were more abundant in deeper soil layers compared to elongated ones, but seed mass and ecological indicator values did not influence the vertical seed bank distribution. Our research draws attention to the potential ecological importance of the deeply buried seeds that may be a source of recovery after severe disturbance. As Vertisols cover 335 million hectares worldwide, these findings can be relevant for many regions and ecosystems globally. We highlight the need for similar studies in other soil and habitat types to test whether the presence of deep buried seeds is specific to soils with Vertic characteristics

Az atomi környezet hatása erősen kötött elektronok atomi átmeneteire = Effects of the atomic environment on atomic transitions of strongly bound electronic states

3d átmeneti fémek (Cu, Ni, Co) rezonáns KLL Auger átmeneteiben rezonáns Raman folyamatokat azonosítottunk és a spektrumok alakját értelmezni tudtuk a 4p be nem töltött elektronállapotok segítségével. Eredményeink szerint a 3d elemek KLL Auger átmeneteiben a multiplett felhasadást a szilárdtest környezet csak kis mértékben változtatja meg. A Cu és Ni fémek rezonáns KLL Auger spektrumaiban kezdeti, ill. végállapoti gerjesztéseknek megfelelő szatelliteket azonosítottunk modellszámításaink és a szatellit-intenzitások fotonenergiától való megfigyelt függése alapján. Szilárd Si és Ge belsőhéj fotoelektron és KLL Auger spektrumaiban meghatároztuk a különböző módusú plazmongerjesztésekből származó járulékokat, függésüket a fotonenergiától és a kísérleti geometriától, kimutatva a belsőhéj-vakanciakeltés jelentős szerepét. Elektron-visszaszórási kísérleteinkkel és az elektrontranszport modellezésével meghatároztuk Ge esetében az elektronok rugalmatlan szórási hatáskeresztmetszetét és közepes szabad úthosszát (IMFP) széles energiatartományban. Eljárásokat dolgoztunk ki és alkalmaztunk különböző anyagoknál az IMFP felületi effektusokra történő korrigálására. Igazoltuk, hogy a rugalmasan visszaszórt elektronok spektroszkópiája alkalmas a felületi H kimutatására és a többszörös szórást figyelembe vevő szimulációnkkal kvantitatíve értelmeztük a polietilénről rugalmasan visszaszórt elektronok spektrumát. A kemény röntgensugárzással keltett elektronok nagy energiafelbontású spektroszkópiájának módszerét sikeresen alkalmaztuk röntgendetektor-válaszfüggvények, ill. ötvözetek komponensei közötti töltésátadás meghatározásában | Resonant Raman processes were identified in the resonant KLL Auger transitions of 3d metals (Cu, Ni, Co). The shape of the Auger lines was interpreted by the help of the unoccupied 4p electronic states. Our results show that the solid environment causes only a small change in the multiplet structure of the KLL Auger spectra of 3d metals. Satellites due to initial or final state excitations were identified in the resonant KLL Auger spectra of Cu and Ni metals, on the basis of our model calculations and of the observed dependence of the satellite intensities on the photon energy. In the core photoemission and KLL Auger spectra of solid Si and Ge, the contributions of plasmon excitations of various mode (dependending on photon energy and experimental geometry) were quantitatively interpreted, showing the great role of core vacancy production. From electron backscattering experiments and modeling the electron transport the cross section of inelastic scattering and the inelastic mean free path (IMFP) of electrons in Ge were determined in a wide energy range. Procedures were elaborated and applied for various materials for correcting IMFPs for surface effects. The applicability of the elastic peak electron spectroscopy for identification of surface H was proved and using our simulation accounting for multiple scattering, the spectrum of electrons backscattered elastically from polyethylene was interpreted quantitatively. The high resolution spectroscopy of electrons excited by hard X-rays was used successfully in determining response function of X-ray detectors and charge transfer between components of alloys

Vertical distribution of soil seed bank and the ecological importance of deeply buried seeds in alkaline grasslands

Background: Soil seed banks play a central role in vegetation dynamics and may be an important source of ecological restoration. However, the vast majority of seed bank studies examined only the uppermost soil layers (0-10 cm); hence, our knowledge on the depth distribution of seed bank and the ecological significance of deeply buried seeds is limited. The aim of our study was to examine the fine-scale vertical distribution of soil seed bank to a depth of 80 cm, which is one of the largest studied depth gradients so far. Our model systems were alkaline grasslands in East-Hungary, characterised by harsh environmental conditions, due to Solonetz soil reference group with Vertic horizon. We asked the following questions: (1) How do the seedling density and species richness of soil seed bank change along a vertical gradient and to what depth can germinable seeds be detected? (2) What is the relationship between the depth distribution of the germinable seeds and the species traits? Methods: In each of the five study sites, four soil cores (4 cm diameter) of 80 cm depth were collected with an auger for soil seed bank analysis. Each sample was divided into sixteen 5-cm segments by depth (320 segments in total). Samples were concentrated by washing over sieves and then germinated in an unheated greenhouse. Soil penetration resistance was measured in situ next to each core location (0-80 cm depth, 1-cm resolution). We tested the number and species richness of seedlings observed in the soil segments (N= 320), using negative binomial generalized linear regression models, in which sampling layer and penetration resistance were the predictor variables. We ran the models for morphological groups (graminoids/forbs), ecological groups (grassland species/weeds) and life-form categories (short-lived/perennial). We also tested whether seed shape index, seed mass, water requirement or salt tolerance of the species influence the vertical distribution of their seed bank. Results: Germinable seed density and species richness in the seed bank decreased with increasing soil depth and penetration resistance. However, we detected nine How germinable seeds of six species even in the deepest soil layer. Forbs, grassland species and short-lived species occurred in large abundance in deep layers, from where graminoids, weeds and perennial species were missing. Round-shaped seeds were more abundant in deeper soil layers compared to elongated ones, but seed mass and ecological indicator values did not influence the vertical seed bank distribution. Our research draws attention to the potential ecological importance of the deeply buried seeds that may be a source of recovery after severe disturbance. As Vertisols cover 335 million hectares worldwide, these findings can be relevant for many regions and ecosystems globally. We highlight the need for similar studies in other soil and habitat types to test whether the presence of deep buried seeds is specific to soils with Vertic characteristics

An appraisal: How notifiable infectious diseases are reported by Hungarian family physicians

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Pacemaker az MR-ben: abszolút kontraindikáció? = Pacemaker in MR: absolute contraindication?

Az MR-vizsgálatok elterjedésével és a pacemaker-technológia fejlődésével bizonyos pacemakerimplantált betegekben is lehetőség nyílik az MR-vizsgálat elvégzésére. A pacemakerbeteg MR-vizsgálatának hazai gyakorlata szegényes, ugyanakkor egyre több irodalmi hivatkozás található a vizsgálatok biztonságos elvégezhetőségére. Célunk volt in vitro kísérletek, vizsgálatok alapján kidolgozni a pacemakerbeteg biztonságos vizsgálatának feltételrendszerét, és bizonyítani a vizsgálat potenciális szövődményeit. Megvizsgáltuk a hazánkban gyakran alkalmazott pacemakertípusok működését és az MR-készülékkel való kölcsönhatását 0,35 és 1,5 T térerejű készülékekben. Az ICD-pacemaker in vitro kísérletek alapján a statikus és változó mágneses térrel is interakciót mutatott, ami a készülék működését jelentősen befolyásolja. Pacemakerfüggő betegeknél az MR-vizsgálatot továbbra is abszolút kontraindikációnak kell tekinteni, de nem pacemakerfüggő betegnél az MR-vizsgálat elvégezhető a megfelelő személyi és tárgyi feltételekkel. A beteg széles körű tájékoztatása után a pacemakert az MR-vizsgálat időtartamára át kell programozni, a vizsgálat befejezésével ellenőrizni és az eredeti programot visszaállítani. | Due to developments in pacemaker technology, implanted pacemakers do not mean an absolute contraindication for MRI examination. However, there are several aspects of MRI examinations that should be considered for safety reasons in pacemaker patients. Based on literature data and own experiments, the safety protocol of MRI examination in pacemaker-implanted patients is described. The interaction of pacemakers – frequently implanted in Hungary – with MR scanners of 0,35 and 1,5 T was studied in vitro. In addition, the cardiac MRI examination of two pacemaker patients is presented. – ICD pacemakers showed strong interaction with static and changing magnetic field that affected pacemaker performance significantly. MRI examination can be safely performed in pacemaker-independent patients. Based on our in vitro and in vivo measurements, MRI examination is still contraindicated in pacemaker-dependent patients. In pacemaker-independent patients blood pressure, ECG monitoring and pulsoximetry are absolutely neccessary, in addition eqiupments for resuscitation should be available. Pacemaker should be specifically programmed before MRI examination and parameters and functionality should be checked in details afterwards