16 research outputs found

    Véleményes valóságverziók Philip K. Dick Figyel az ég című regényében

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    A recurring theme in science fiction literature is the blurring of the lines between virtual reality and reality, somewhat mirroring the experience of today’s Internet culture. In Philip K. Dick’s 20th-century work we can easily identify 21st-century online problems, such as disinformation, filterbubbles, perception of reality, or the effects of media manipulation. However, this does not mean that Philip K. Dick predicted the social and information problems of our time, but he dealt with phenomena that had taken root in culture and society at the beginning of the spread of mass media. In his novels published from the 1950s until his death, the author regularly dealt with the possibilities of knowing reality, virtual realities, how the world can be perceived and interpreted, or it is even directly accessible or not. In the novel Eye in the Sky there are many places where the phenomena that we tend to attribute to platform media and information overload are themed

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    Porous aluminum oxide insulation materials tested in space mission

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    The eventual aim of this research work was to develop a new low-cost synthesis route to produce ultralight aluminum oxide ceramic fibers for high temperature insulation. This paper mainly focuses on the application of Al 2 O 3 fibers as insulation materials in space vehicles. The study extended to check the fibers during the launch and in the conditions of space by a satellite test. The materials were monitored by thermo-vacuum and vibration tests before the launch. The long-term stability, the daily maximum and minimum temperature, and the temperature fluctuation were investigated in the satellite test. The data derived from satellite was collected in about 9 months. The other focus of this study was the characterization of fibers at high temperature. Al 2 O 3 fibers were prepared by a new solution method and electrospinning technique. The developed Al 2 O 3 fibers can be characterized by 0.035–0.037 W⋅mK −1 thermal conductivity, excellent heat resistance (up to 1600 °C), and good flexibility

    Inflammasome activation in peritumoral astrocytes is a key player in breast cancer brain metastasis development

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    Inflammasomes, primarily responsible for the activation of IL-1β, have emerged as critical regulators of the tumor microenvironment. By using in vivo and in vitro brain metastasis models, as well as human samples to study the role of the NLRP3 inflammasome in triple-negative breast cancer (TNBC) brain metastases, we found NLRP3 inflammasome components and IL-1β to be highly and specifically expressed in peritumoral astrocytes. Soluble factors from TNBC cells induced upregulation and activation of NLRP3 and IL-1β in astrocytes, while astrocyte-derived mediators augmented the proliferation of metastatic cells. In addition, inhibition of NLRP3 inflammasome activity using MCC950 or dampening the downstream effect of IL-1β prevented the proliferation increase in cancer cells. In vivo, MCC950 reduced IL-1β expression in peritumoral astrocytes, as well as the levels of inflammasome components and active IL-1β. Most importantly, significantly retarded growth of brain metastatic tumors was observed in mice treated with MCC950. Overall, astrocytes contribute to TNBC progression in the brain through activation of the NLRP3 inflammasome and consequent IL-1β release. We conclude that pharmacological targeting of inflammasomes may become a novel strategy in controlling brain metastatic diseases

    Effect of genetic and environmental influences on hepatic steatosis: A classical twin study based on computed tomography

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    Background and aims: Non-alcoholic fatty liver disease (NAFLD) increases cardiovascular morbidity and mortality, and carries poor long-term hepatic prognosis. Data about the role of genetic and environmental factors in the hepatic lipid accumulation are limited. The aim of the study was to evaluate the genetic and environmental impact on the hepatic lipid accumulation within a cohort of adult twin pairs. Patients and methods: We investigated 182 twin subjects [monozygotic (MZ, n 5 114) and dizygotic (DZ, n 5 68) same-gender twins (age 56.0 ± 9.6 years; BMI 27.5 ± 5.0 kg/m2 ; females 65.9%)] who underwent computed tomography (CT) with a 256-slice scanner. Using nonenhanced CT-images, we calculated the average value of hepatic attenuation [expressed in Hounsfield unit (HU)] suggesting hepatic lipid content. Crude data were adjusted to age, sex, BMI and HbA1c values. Intra-pair correlations were established, and structural equation models were used for quantifying the contribution of additive genetic (A), common environmental (C) and unique environmental (E) components to the investigated phenotype. Results: The study cohort represented a moderately overweight, middle-aged Caucasian population. There was no significant difference between MZ and DZ twin subjects regarding hepatic CT-attenuation (57.9 ± 12.6 HU and 59.3 ± 11.7 HU, respectively; p 5 0.747). Age, sex, BMI and HbA1c adjusted co-twin correlations between the siblings showed that MZ twins have stronger correlations of HU values than DZ twins (rMZ 5 0.592, p < 0.001; rDZ 5 0.047, p 5 0.690, respectively). Using the structural equation model, a moderate additive genetic dependence (A: 38%, 95% CI 15–58%) and a greater unique environmental influence (E: 62%, 95% CI 42–85%) was found. Common environmental influence was not identified (C: 0%). Conclusion: The results of our classical CT-based twin study revealed moderate genetic and greater environmental influences on the phenotypic appearance of hepatic steatosis, commonly referred to as NAFLD. Favorable changes of modifiable environmental factors are of great importance in preventing or treating NAFLD

    A fotonszámláló detektoros CT működési alapelve, előnyei és jelentősége a klinikai gyakorlatban = Photoncounting-detector CT: Basic principles, advantages and implications in clinical practice

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    Az elmúlt évtizedben fizikai és preklinikai vizsgálatokkal igazolták az alapjaiban új típusú, fotonszámláló komputertomográfiás (CT) detektor kiváló képalkotási tulajdonságait, míg napjainkban a páréves klinikai felhasználás egyre szélesebb körű tapasztalatait veszik számba. A klinikai gyakorlatban elterjedt, hagyományos CT-berendezésekben energiaintegráló detektorok (EID) találhatók, melyek indirekt konverziós technológiával alakítják át a röntgenfotonok energiáját elektromos jellé. Ezzel ellentétben a fotonszámláló CT detektorai (PCD) közvetlenül és magasabb hatásfokkal képesek elektromos jellé alakítani a röntgenfotonok energiáját, megszámlálni az egyes röntgenfotonok által létrehozott töltéseket és mérni azok energiaszintjét. Az új PCD-technológia számos előnyt nyújt a hagyományos EID-technológiával összevetve: egyrészt kisebb sugárterhelés mellett jobb térbeli felbontású, kedvezőbb jel/zaj arányú, kevesebb sugárkeményedési („beam-hardening”) műterméket tartalmazó és alacsonyabb elektronikus zajjal terhelt CT-képeket hoz létre, másrészt lehetővé teszi a spektrális képalkotást, valamint csökkentett dózisú kontrasztanyag alkalmazására is lehetőséget ad. Összefoglaló közleményünk a PCD-CT műszaki és fizikai alapelveit ismerteti, valamint áttekintést nyújt annak előnyeiről és a klinikai gyakorlatban való felhasználásáról. | Over the last decade, an esentially new type of computed tomography (CT) detector, namely the photoncounting detector has demonstrated its superior capabilities over traditional CT detectors in both physical and preclinical evaluations, while is now at the stage of early clinical experiences. Conventional CT scanners available today for routine clinical practice use energy integrated detectors (EID) which rely on indirect conversion technology. In contrary, the newly-introduced photon-counting detectors (PCD) utilize a direct conversion method allowing to count the number of x-ray photons and carry detailed information about the energy level of each individual x-ray photon. Due to the fundamental changes in the physical mechanisms responsible for photon detection and signal creation, PCDs have several benefits over traditional CT detectors. In comparison to current CT technology, PCDCT can produce better spatial resolution, reduced electronic noise with a higher contrast-to-noise ratio, reduced beam-hardening and metal artifacts. Furthermore, from the spectral information, this new technology is capable to reconstruct virtual monoenergetic images and optimize iv. contrast agent dose. In our current review article, technical principles and physics of PCDs and, in addition, early clinical experiences with their applications are summarized

    Multiple SARS-CoV-2 Introductions Shaped the Early Outbreak in Central Eastern Europe: Comparing Hungarian Data to a Worldwide Sequence Data-Matrix

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    Severe Acute Respiratory Syndrome Coronavirus 2 is the third highly pathogenic human coronavirus in history. Since the emergence in Hubei province, China, during late 2019, the situation evolved to pandemic level. Following China, Europe was the second epicenter of the pandemic. To better comprehend the detailed founder mechanisms of the epidemic evolution in Central-Eastern Europe, particularly in Hungary, we determined the full-length SARS-CoV-2 genomes from 32 clinical samples collected from laboratory confirmed COVID-19 patients over the first month of disease in Hungary. We applied a haplotype network analysis on all available complete genomic sequences of SARS-CoV-2 from GISAID database as of 21 April 2020. We performed additional phylogenetic and phylogeographic analyses to achieve the recognition of multiple and parallel introductory events into our region. Here, we present a publicly available network imaging of the worldwide haplotype relations of SARS-CoV-2 sequences and conclude the founder mechanisms of the outbreak in Central-Eastern Europe

    A működési kockázat becslési problémáiról

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    A dolgozat a hitelintézeteket érintő egyik kockázati típussal, a működési kockázattal és annak becslési problémáival foglalkozik. A hatályos rendelkezések szerint a hitelintézeteknek fedezetet kell képeznie a különböző kockázatokra a biztonságosabb működés érdekében. A fedezet értékének meghatározása matematikai modellek által történik.MSc/MAAlkalmazott matematikusg

    A Tracking Method in FM Broadcast-based Passive Radar Systems

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