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51.
Tibor Károly Fábián Anita Beck Pál Fejérdy Péter Hermann Gábor Fábián 《International journal of molecular sciences》2015,16(3):5945-5974
The gustatory system plays a critical role in determining food preferences and food intake, in addition to nutritive, energy and electrolyte balance. Fine tuning of the gustatory system is also crucial in this respect. The exact mechanisms that fine tune taste sensitivity are as of yet poorly defined, but it is clear that various effects of saliva on taste recognition are also involved. Specifically those metabolic polypeptides present in the saliva that were classically considered to be gut and appetite hormones (i.e., leptin, ghrelin, insulin, neuropeptide Y, peptide YY) were considered to play a pivotal role. Besides these, data clearly indicate the major role of several other salivary proteins, such as salivary carbonic anhydrase (gustin), proline-rich proteins, cystatins, alpha-amylases, histatins, salivary albumin and mucins. Other proteins like glucagon-like peptide-1, salivary immunoglobulin-A, zinc-α-2-glycoprotein, salivary lactoperoxidase, salivary prolactin-inducible protein and salivary molecular chaperone HSP70/HSPAs were also expected to play an important role. Furthermore, factors including salivary flow rate, buffer capacity and ionic composition of saliva should also be considered. In this paper, the current state of research related to the above and the overall emerging field of taste-related salivary research alongside basic principles of taste perception is reviewed. 相似文献
52.
Chao Wen Alexander G. Banshchikov Yury Y. Illarionov Werner Frammelsberger Theresia Knobloch Fei Hui Nikolai S. Sokolov Tibor Grasser Mario Lanza 《Advanced materials (Deerfield Beach, Fla.)》2020,32(34):2002525
Mechanically exfoliated 2D hexagonal boron nitride (h-BN) is currently the preferred dielectric material to interact with graphene and 2D transition metal dichalcogenides in nanoelectronic devices, as they form a clean van der Waals interface. However, h-BN has a low dielectric constant (≈3.9), which in ultrascaled devices results in high leakage current and premature dielectric breakdown. Furthermore, the synthesis of h-BN using scalable methods, such as chemical vapor deposition, requires very high temperatures (>900 °C) , and the resulting h-BN stacks contain abundant few-atoms-wide amorphous regions that decrease its homogeneity and dielectric strength. Here it is shown that ultrathin calcium fluoride (CaF2) ionic crystals could be an excellent solution to mitigate these problems. By applying >3000 ramped voltage stresses and several current maps at different locations of the samples via conductive atomic force microscopy, it is statistically demonstrated that ultrathin CaF2 shows much better dielectric performance (i.e., homogeneity, leakage current, and dielectric strength) than SiO2, TiO2, and h-BN. The main reason behind this behavior is that the cubic crystalline structure of CaF2 is continuous and free of defects over large regions, which prevents the formation of electrically weak spots. 相似文献
53.
Virtual Reality - The interaction time of students who did spatial ability tests in a virtual reality environment is analyzed. The spatial ability test completion times of 240 and 61 students were... 相似文献
54.
Xu Jing Yury Illarionov Eilam Yalon Peng Zhou Tibor Grasser Yuanyuan Shi Mario Lanza 《Advanced functional materials》2020,30(18)
The continuous miniaturization of field effect transistors (FETs) dictated by Moore's law has enabled continuous enhancement of their performance during the last four decades, allowing the fabrication of more powerful electronic products (e.g., computers and phones). However, as the size of FETs currently approaches interatomic distances, a general performance stagnation is expected, and new strategies to continue the performance enhancement trend are being thoroughly investigated. Among them, the use of 2D semiconducting materials as channels in FETs has raised a lot of interest in both academia and industry. However, after 15 years of intense research on 2D materials, there remain important limitations preventing their integration in solid‐state microelectronic devices. In this work, the main methods developed to fabricate FETs with 2D semiconducting channels are presented, and their scalability and compatibility with the requirements imposed by the semiconductor industry are discussed. The key factors that determine the performance of FETs with 2D semiconducting channels are carefully analyzed, and some recommendations to engineer them are proposed. This report presents a pathway for the integration of 2D semiconducting materials in FETs, and therefore, it may become a useful guide for materials scientists and engineers working in this field. 相似文献
55.
Hasan K. M. Faridul Horváth Péter György Alpár Tibor 《Journal of Materials Science》2021,56(26):14381-14415
Journal of Materials Science - Fabric-based laminated composites are used considerably for multifaceted applications in the automotive, transportation, defense, and structural construction sectors.... 相似文献
56.
Surinder?SinghEmail authorView authors OrcID profile Sukhbir?Singh Nada?Badraoui Tibor?Berceli Akram?Alomainy 《Photonic Network Communications》2017,34(2):288-297
In this paper, the design and analysis of the all-optical up- and down-wavelength converter based on four-wave mixing (FWM) effect of semiconductor optical amplifier Mach–Zehnder interferometer (SOA-MZI) have been presented. The return-to-zero (RZ) modulated data signal at a bit rate of 60 Gbps has been evaluated for error-free operation to show the feasibility of proposed system at different pump wavelength. The converted signal power and quality factor are investigated as the function of variable signal power and pump power. The optimized operating input signal power of ?5 dBm with Q-factor of \(\sim \)28 dB for RZ modulated signal by using SOA-MZI structure with enhanced FWM effect. The important contribution of these investigations that it is possible to expand the optical network with limited available channel bandwidth by utilizing the wavelength converter and gives an approach to implement wavelength converter for future hybrid optical access networks. 相似文献
57.
The use of cinchona alkaloids (cinchonidine, cinchonine, quinine, quinidine, α-isocinchonine, α-isoquinidine, γ-isoquinidine)
in the Orito reaction (hydrogenation of ethyl pyruvate and ethyl benzoylformate) strongly supports the structure of the intermediate
complex (cinchona alkaloid “anti‐open” conformer–pyruvate 1 : 1 complex); in addition, so far unknown stereochemical conditions
have been identified and the utilization of rigid cinchona conformers in the study of asymmetric syntheses have been generalized.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
58.
59.
Orsolya Kinga Gondor Judit Tajti Kamirn ron Hamow Imre Majlth Gabriella Szalai Tibor Janda Magda Pl 《International journal of molecular sciences》2021,22(21)
Although the relationship between polyamines and photosynthesis has been investigated at several levels, the main aim of this experiment was to test light-intensity-dependent influence of polyamine metabolism with or without exogenous polyamines. First, the effect of the duration of the daily illumination, then the effects of different light intensities (50, 250, and 500 μmol m–2 s–1) on the polyamine metabolism at metabolite and gene expression levels were investigated. In the second experiment, polyamine treatments, namely putrescine, spermidine and spermine, were also applied. The different light quantities induced different changes in the polyamine metabolism. In the leaves, light distinctly induced the putrescine level and reduced the 1,3-diaminopropane content. Leaves and roots responded differently to the polyamine treatments. Polyamines improved photosynthesis under lower light conditions. Exogenous polyamine treatments influenced the polyamine metabolism differently under individual light regimes. The fine-tuning of the synthesis, back-conversion and terminal catabolism could be responsible for the observed different polyamine metabolism-modulating strategies, leading to successful adaptation to different light conditions. 相似文献
60.
Operation of fixed bed reactors with periodic flow reversal as proposed by Matros and co-workers is an unconventional mode of operation for exothermic, equilibrium limited catalytic reactions. In the present paper, reverse flow ammonia synthesis at 240–300 bar over a promoted iron catalyst is considered. The catalyst had a particle size of 1.0–1.5 mm to neglect the intra- and interparticle transport intrusions. Temperature profiles, which developed and moved back and forth through the laboratory scale reactor, depending upon the direction of the flow, and the exit ammonia concentration were monitored. The time average ammonia concentration observed in the non-steady-state of operation was exceeded by 5–27% the ammonia concentration obtained in similar but under steady-state conditions. The enhancement in the ammonia production was mainly due to the transient state of the catalyst surface and the dynamic behavior of the reactor bed. 相似文献