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Trendy v dlhodobých zmenách využívania krajiny marginálneho územia na príklade zo strednej Európy (Šahy – Slovensko)
No full textThe article presents changes in land use in the marginalized area of Šahy town on the Slovak-Hungarian border in relation to socio-economic changes. The aim of the research was to outline future development trends and propose management measures for the future in terms of the optimal functioning of this area. The assessment of the historical development of the landscape is based on the natural potential of the landscape, to which relevant socioeconomic characteristics are added. These create and characterize the theoretical basis of the processed issue and the methodological concept for further processing. Analyses of the development and use of the landscape in the context of the real development of the landscape according to historical time horizons from the first military mapping (1769 - 1784) to the present state are conditioned by field research. Changes in land use are observed through the analysis of elements of the secondary landscape structure (SLS) and further processed methods of geographic information systems (GIS) and statistical evaluation of data. The evaluated changes are typical for the entire territory of the post-communist countries of Central Europe. They include peripheral regions in terms of environmental preservation depending on urban infrastructure. One of the conclusions of the research is the proposals for management measures for the Šahy town in connection with its strategic planning and strategic documents. The measures are divided into 3 areas - economic, social and environmental. We have determined positive or low in relation to the development of the country in the future.V článku sú prezentované zmeny využívania krajiny v marginalizovanom území mesta Šahy na slovensko-maďarskej hranici vo vzťahu k socio-ekonomickým zmenám. Cieľom výskumu bolo načrtnutie budúcich trendov vývoja a návrh manažmentových opatrení do budúcnosti z hľadiska optimálneho fungovania tohto územia. Hodnotenie historického vývoja krajiny vychádza z prírodného potenciálu krajiny, ku ktorému sa pridáva relevantná socio-ekonomická charakteristika. Tieto vytvárajú a charakterizujú teoretické východiská spracovávanej problematiky a metodickú koncepciu pre ďalšie spracovanie. Analýzy vývoja a využitia krajiny v kontexte reálneho vývoja krajiny podľa historických časových horizontov od prvého vojenského mapovania (1769 – 1784) k súčasnému stavu sú podmienené terénnym výskumom. Zmeny využívania krajiny sú pozorované prostredníctvom analýzy prvkov sekundárnej krajinnej štruktúry a ďalej spracované využitím metód geografických informačných systémov (GIS) a štatististickým hodnotením dát. Vyhodnotené zmeny sú typické pre cele územie post komunistických krajín strednej Európy. Zahŕňajú periferálne regióny v zmysle zachovania životného prostredia v závislosti od mestskej infraštruktúry. Jedným zo záverov výskumu sú návrhy
manažmentových opatrení pre mesto Šahy s nadväznosťou na jeho strategické plánovanie a strategické dokumenty. Opatrenia sú rozdelené na 3 oblasti – hospodárske, sociálne a environmentálne. Určili sme 20 lokalít pozitívnych alebo negatívnych vo vzťahu k vývoju krajiny do budúcnosti
Prediction Model for Cladding of Ni-Alloys During CMT Welding Process by Using Fuzzy Logic
No full textMaintaining stable conditions during cladding of Ni-alloys is of great importance for achieving a uniform quality of the cladded layer. As cladding of Ni-alloy is performed by the MAG-CMT welding process with a four-component gas on the base material (membrane wall), it cannot be always performed with the same tolerances. Therefore, the MAG-CMT welding process requires constant real-time monitoring and detection of faults in the cladded layer. This paper presents a model based on fuzzy logic. The created model is tested to confirm the proposed prediction model. The prediction accuracy was 93.67%, which proves that the created model can be used for cladding in new automated welding systems. Application of the obtained model shall enable the development of a monitoring system that can identify and classify certain defects occurring during the MAG-CMT welding process
Metabolic insights into the warfarin-mango interaction: A pilot study integrating clinical observations and metabolomics
No full textBackground and purpose
Warfarin is a widely prescribed oral anticoagulant for the prevention and treatment of thromboembolic events, frequently used in patients with atrial fibrillation. However, its effectiveness is often challenged by a narrow therapeutic range and significant inter-patient variability in dosage requirements and treatment responses. Drug interactions remain a critical concern, as they heighten the risk of supratherapeutic anticoagulation. Reports of interactions between warfarin and mango have documented cases of elevated international normalized ratio (INR) following mango consumption, although the underlying molecular mechanisms remain unclear.
Experimental approach
This study investigates the molecular basis of the warfarin-mango interaction using proton nuclear magnetic resonance (1H-NMR)-based metabolomics. In a pre-post design study, plasma samples were collected from patients on long-term warfarin therapy (>6 months) who exhibited supratherapeutic INR levels after consuming mango. After a two-week discontinuation of mango consumption, additional plasma samples were collected once INR levels returned to the therapeutic range.
Key results and conclusion
This is the first study to utilize 1H-NMR metabolomics to explore warfarin-mango interactions, integrating clinical observations with metabolic insights. Findings suggest that a reduction in glycerol 3-phosphate may impair glycolysis, disrupting platelet activation and contributing to the elevated INR levels observed in all patients. These results underscore the potential for 1H-NMR metabolomics to elucidate drug-food interactions, advancing personalized anticoagulant management and improving patient safety
Tuneable carbon dots coated iron oxide nanoparticles as superior T1 contrast agent for multimodal imaging
No full textAbstract
Background and purpose
Multifunctional hybrid nanoparticles garner heightened interest for prospective biomedical applications, including medical imaging and medication administration, owing to their synergistic benefits of constituent components. Therefore, we demonstrated an optimized protocol for synthesizing magnetofluorescent nanohybrids comprising fluorescent carbon dots with magnetic nanoparticles.
Experimental approach
Carbon dot-coated iron oxide nanoparticles (CDs@Fe2O3) were synthesized with varying citric acid concentrations by a one-pot hydrothermal synthesis method for the development of a low-cost and biocompatible contrast agent (CA) for enhanced multimodal imaging (fluorescent and T1 and T2 weighted magnetic resonance imaging (MRI)) to replace the conventional CAs.
Key results
The physicochemical characterization of the synthesized CDs@Fe2O3 revealed that 3 g of citric acid used for the synthesis of nanoparticles, keeping Fe(II) and Fe(III) ratio 1:2 provides higher stability of -78 mV zeta potential, saturation magnetization of 24 emu/g, with a hydrodynamic diameter of 68 nm. Carbon coating affects surface spins on Fe2O3, resulting in fewer surface-based relaxation centres, making T1 relaxation relatively more prominent. Furthermore, the surface-engineered iron oxide NPs are efficient in producing both T1 and T2 weighted MRI as well as fluorescence-based imaging. The molar relaxivity and molar radiant efficiency derived from phantom studies demonstrate their effectiveness in multimodal medical imaging. The cytotoxicity assay, haemolysis assay, haematology, and histopathology studies show that the optimized CDs@Fe2O3 are biocompatible, haemocompatible, and negligibly toxic.
Conclusion
We can conclude the significant potency of CDs@Fe2O3 for multimodal diagnosis
Neural Network Identification of the Parameters of Ultra-High-Performance Concrete Bridges
No full textThis study focuses on an ultra-high performance concrete bridge, utilizing the natural fundamental frequency and mid-span deflection as input data to construct a backpropagation neural network prediction model. The model inversely identifies two critical material parameters of ultra-high performance concrete - elastic modulus and unit weight - to minimize discrepancies between actual values and design values, thereby establishing a computational model that better approximates the real bridge structure. The results demonstrate the feasibility of the backpropagation neural network prediction model for identifying and correcting structural parameters, with the model exhibiting high prediction accuracy. This approach provides a valuable reference for acquiring actual structural parameters in bridge engineering
DHANet: Dual-Stage Hybrid Attention Network for Blind Image Super-Resolution
No full textIn recent years, blind image super-resolution (SR) methods have demonstrated promising performance but remain limited by inaccurate blur kernel evaluation and difficulties in global feature extraction. This paper introduces DHANet, a Dual-Stage Hybrid Attention Network, combining CNN and Transformer-based modules for blind image SR. DHANet includes a blur kernel predictor, a hybrid attention dual-path module (HADM) for enhanced feature extraction, and a feature refinement module (FRM) for reconstructing refined high-resolution images. Experiments on benchmark datasets demonstrate superior performance in terms of quality and efficiency. Specifically, our method improves the average PSNR metric on four benchmark datasets from 34.98 to 35.29 at SR2 compared to the second-best comparison method, and shows varying degrees of improvement in PSNR and SSIM metrics on different datasets at SRx3 and SRx4
Ključne prekretnice, akteri i policy instrumenti iliberalnog zaokreta medijskih sustava Mađarske i Poljske
No full textZemlje Srednje i Istočne Europe od 1990-ih godina suočavaju se s korjenitim i brzim političkim, društvenim i ekonomskim promjenama koje su nagovijestile kraj dotadašnje monopolističke kontrole države nad medijima. Međutim, u dijelu zemalja regije uočava se trend izraženoga demokratskog nazadovanja i iliberalnog zaokreta koji se odražava i na njihove medijske sustave. Medijski sustavi pritom imaju ključnu ulogu jer upravo kroz njih vladajuće strukture operacionaliziraju iliberalne politike i ostvaruju simboličku i institucionalnu dominaciju nad javnom sferom. Iako se njegove naznake mogu uočiti i u drugim zemljama, stručnjaci su složni u ocjeni da je trend iliberalnog zaokreta najizraženiji u Mađarskoj i Poljskoj – zemljama koje se donedavno smatralo predvodnicama političke demokratizacije i ekonomske liberalizacije, a koje posljednjih godina derogiraju dostignute demokratske standarde, ugrožavaju vladavinu prava EU-a i kontinuirano padaju na ljestvicama slobode (medija). Koristeći aditivni indeks konceptualno povezanih pokazatelja iz baza podataka V-Dem instituta, ovaj rad kontekstualizira te dijakronijski i usporedno razmatra ključne prekretnice, aktere i policy instrumente kojima se ostvaruje iliberalni zaokret medijskih sustava Mađarske i Poljske. Analiza pokazuje da je ključna prekretnica iliberalnog zaokreta u objema zemljama bio dolazak desno-populističkih stranaka na vlast – Fidesza u Mađarskoj 2010. i PiS-a u Poljskoj 2015. godine, koje od tada koriste slične policy instrumente s ciljem uspostave i održavanja administrativne i političke kontrole nad javnim, ali i komercijalnim medijima. Od trenutka preuzimanja vlasti Fidesz i PiS, uz podršku određenih interesnih skupina, otvoreno i agresivno interveniraju u medijski sustav, opravdavajući svoje poteze usko definiranim nacionalnim interesima i potrebom zaštite suvereniteta od konstruiranih prijetnji te provode paternalističku i partikularističku medijsku politiku kojom medijske resurse redistribuiraju pojedincima koji su bliski vlasti. Utvrđivanjem sličnosti i razlika koje su dovele do erozije slobode medija u Mađarskoj i Poljskoj, rad doprinosi boljem razumijevanju uvjeta i manifestacija iliberalnog zaokreta te ukazuje na potrebu za daljnjim normativnim, teorijskim, empirijskim i usporednim razmatra
njima odnosa medija i politike u Srednjoj i Istočnoj Europi
Evaluation of bioactive components and antioxidant activities of Rose canina L., Viburnum opulus L., Berberis vulgaris L. and Berberis integerrima L. subjected to different extraction methods
No full textRose hip (Rosa canina L.), gilaburu (Viburnum opulus L.), barberry (Berberis vulgaris L.) and black barberry (Berberis integerrima L.) are important endemic plants of Turkiye. This study determined the bioactive components, including total phenolic content, flavonoid compounds, and anthocyanin amounts. Antioxidant activity values of Rosa canina L., Viburnum opulus L., Berberis vulgaris L. and Berberis integerrima L. fruits grown in Türkiye were also evaluated after different extractions. According to the results, the highest total phenolic content was determined in the methanol extract of Berberis integerrima L.fruit as 3544.84 (mg GAE/100 g DM). The order of the total amount of phenolic substance for all three solvent extraction systems, from the highest to the lowest, was determined as: Berberis integerrima L.>Viburnum opulus L.>Berberis vulgaris L.>Rose canina L. In terms of total flavonoids, Berberis integerrima L. fruit extracted with methanol had the highest value of 2098.88 (mg CE/100 g). The order of total amount of flavonoid substance for all three solvent extraction systems, from the highest to the lowest, was determined as Berberis integerrima L. > Viburnum opulus L. > Berberis vulgaris L. > Rose canina was detected. The highest amount of Trolox equivalent (DPPH)(ABTS+) was determined as 2.95-3.30 (mM Trolox/100 g DM) in Berberis integerrima L. extracted with methanol. The highest total amount of anthocyanins found in the extracts was obtained for Berberis integerrima L. The highest amounts of vitamin C extracted with ethanol, methanol and water was determined for Berberis integerrima L.24.60; 33.22; 29.22 (mg/ 100 g), respectively. The highest value for CD, CI and T was obtained for Berberis integerrima L. extracted with methanol. The highest score for % R, %Y and % B was obtained for Berberis vulgaris L. exacted with water, for Berberis integerrima L. extracted with ethanol and Berberis integerrima L. extracted with water, respectively. The results demonstrated that the extraction solvent has a critical importance for the releasing of bioactive compounds for each used materials
Kraj demokracije? Istina u doba „infokracije” prema Byung-Chul Hanu
No full textČlanak istražuje suvremene izazove s kojima se demokracija suočava pod utjecajem digitalne tehnologije i promjene paradigmi moći, prema analizama Byung-Chul Hana. Manipulacija javnim mnijenjem putem „psihopolitike” i algoritama prijeti temeljima demokracije. Međutim, snaga demokracije leži u njezinoj ranjivosti i otvorenosti, što je slično kršćanskom konceptu solidarnosti i priznavanja snage u slabosti. Autor predlaže poetičku obnovu politike kroz obrede, narative i hrabro govorenje istine, čime bi se stvorila integracija digitalnih i humanističkih aspekata te osigurao autentičan demokratski poredak.The paper explores contemporary challenges faced by democracy due to digital technology and shifts in power paradigms, drawing on Byung-Chul Han’s analyses. The manipulation of public opinion through “psychopolitics” and algorithms threatens core democratic values. However, democracy’s strength lies in its vulnerability and openness, like the Christian concepts of solidarity and finding strength in weakness. The author suggests a poetic renewal of politics through rituals, narratives, and courageous truth-telling aiming to integrate digital and humanistic elements and foster an authentic democratic framewor