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61.
Antiviral type I interferons (IFN) produced in the early phase of viral infections effectively inhibit viral replication, prevent virus-mediated tissue damages and promote innate and adaptive immune responses that are all essential to the successful elimination of viruses. As professional type I IFN producing cells, plasmacytoid dendritic cells (pDC) have the ability to rapidly produce waste amounts of type I IFNs. Therefore, their low frequency, dysfunction or decreased capacity to produce type I IFNs might increase the risk of severe viral infections. In accordance with that, declined pDC numbers and delayed or inadequate type I IFN responses could be observed in patients with severe coronavirus disease (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), as compared to individuals with mild or no symptoms. Thus, besides chronic diseases, all those conditions, which negatively affect the antiviral IFN responses lengthen the list of risk factors for severe COVID-19. In the current review, we would like to briefly discuss the role and dysregulation of pDC/type I IFN axis in COVID-19, and introduce those type I IFN-dependent factors, which account for an increased risk of COVID-19 severity and thus are responsible for the different magnitude of individual immune responses to SARS-CoV-2. 相似文献
62.
Richrd Sink Kristf Rada Anna Kollr Petra Mohcsik Mikls Tenk Csaba Fekete Balzs Gereben 《International journal of molecular sciences》2022,23(23)
Thyroid hormone (TH) signaling is a prerequisite of normal tissue function. Environmental pollutants with the potential to disrupt endocrine functions represent an emerging threat to human health and agricultural production. We used our Thyroid Hormone Action Indicator (THAI) mouse model to study the effects of tetrabromobisphenol A (TBBPA; 150 mg/bwkg/day orally for 6 days) and diclazuril (10.0 mg/bwkg/day orally for 5 days), a known and a potential hormone disruptor, respectively, on local TH economy. Tissue-specific changes of TH action were assessed in 90-day-old THAI mice by measuring the expression of a TH-responsive luciferase reporter in tissue samples and by in vivo imaging (14-day-long treatment accompanied with imaging on day 7, 14 and 21 from the first day of treatment) in live THAI mice. This was followed by promoter assays to elucidate the mechanism of the observed effects. TBBPA and diclazuril impacted TH action differently and tissue-specifically. TBBPA disrupted TH signaling in the bone and small intestine and impaired the global TH economy by decreasing the circulating free T4 levels. In the promoter assays, TBBPA showed a direct stimulatory effect on the hdio3 promoter, indicating a potential mechanism for silencing TH action. In contrast, diclazuril acted as a stimulator of TH action in the liver, skeletal muscle and brown adipose tissue without affecting the Hypothalamo-Pituitary-Thyroid axis. Our data demonstrate distinct and tissue-specific effects of TBBPA and diclazuril on local TH action and prove that the THAI mouse is a novel mammalian model to identify TH disruptors and their tissue-specific effects. 相似文献
63.
Moraglia Giampaolo; Maloney Kevin P.; Fekete Eva M.; Al-Basi Katharina 《Canadian Metallurgical Quarterly》1989,43(1):1
Conducted 2 experiments in which 3 adults with normal or corrected-to-normal vision searched for a chromatic target among colored background items. Findings suggest that visual behavior as based on the operations of the preattentive visual system was either unaffected by factors (e.g., extent of target background similarity, background variance) that determined the level of complexity of a display or task or inhibited by their occurrence. In attention-based visual behavior, these factors exerted influence in a graded manner by modulating ease and speed with which the display was searched. Results support the heuristic value of the notion of A. Treisman (1985, 1986) of the availability of a feature map as a basis for determining the nature of a color search. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
64.
True scale models of vertical-axis wind turbines do not function at the small scales which are necessary for turbine array simulation. In past model tests vertical-axis wind turbines have been viewed as devices which have a given drag coefficient and a certain intensity of turbulence in their wakes. These features were modelled in the wind tunnel by stationary simulators when the optimum spacing in vertical-axis wind-turbine arrays was studied.In this paper, it is suggested that rotating vertical-axis machines may be spaced more closely than indicated by past model tests, owing to the enhanced mixing of laterally deflected wakes with the surrounding flow. This wake deflection has not been modelled in the past.In the present study the mean flow energy content of the boundary layer was measured in a wind tunnel downstream of groups of stationary simulators when the turbulence intensity and the drag were modelled both with and without reproduction of the deflected wake of rotating machines. Comparison of the results shows the mean flow energy content of the boundary layer to be up to ~ 10% higher when wake deflection is reproduced. The results of past model tests are expected, therefore, to be conservative. 相似文献
65.
Particulate-filled composites were prepared from CaCO 3 and polymer matrices of various acid-base characters. Interfacial interaction of the components was characterized by the reversible work of adhesion, which was calculated either from dipole-dipole or acid-base interactions. The thickness of the spontaneously formed interlayer was derived from the tensile strength of the composites. The results proved that acid-base interactions play an important role in interphase formation. The strength of interfacial adhesion is determined by the joint effect of dispersion forces and acid-base interactions. Stronger interaction leads to a thicker interphase with decreased mobility. Treatment of CaCO 3 with an aliphatic fatty acid leads to a decrease in the strength of interaction, and to changes both in the thickness and properties of the interphase. In composites containing coated fillers, acid-base interactions influence composite properties less due to the neutral character of the surface. 相似文献
66.
Henr N Bezerianos A Fekete JD 《IEEE transactions on visualization and computer graphics》2008,14(6):1317-1324
Exploring communities is an impor tant task in social network analysis. Such communities are currently identified using clustering methods to group actors. This approach often leads to actors belonging to one and only one cluster, whereas in real life a person can belong to several communities. As a solution we propose duplicating actors in social networks and discuss potential impact of such a move. Several visual duplication designs are discussed and a controlled experiment comparing network visualization with and without duplication is performed, using 6 tasks that are impor tant for graph readability and visual interpretation of social networks. We show that in our experiment, duplications significantly improve community-related tasks but sometimes interfere with other graph readability tasks. Finally, we propose a set of guidelines for deciding when to duplicate actors and choosing candidates for duplication, and alternative ways to render them in social network representations. 相似文献
67.
Atmospheric deposition of polycyclic aromatic hydrocarbons (PAHs) in mosses (Hypnum cupressiforme) in Hungary 总被引:3,自引:0,他引:3
Otvös E Kozák IO Fekete J Sharma VK Tuba Z 《The Science of the total environment》2004,330(1-3):89-99
The atmospheric deposition of polycyclic aromatic hydrocarbons (PAHs) was investigated in Hungary by analyzing a moss (Hypnum cupressiforme) species as a bioindicator. In the autumn of 1997, samples were collected at 29 sites distributed across Hungary. The concentrations of total PAH at these sites were in the range of 0.1567-10.45 x 10(4) microg kg(-1) with a mean value of 1.87 x 10(4) microg kg(-1). More than 99% of the total PAHs atmospheric deposition were low molecular weight PAHs (up to 3 ring compounds). The total PAH values showed no correlation with metal concentrations. However, most of the sites in this region showed a positive linear relationship between PAHs levels and traffic volume (r2 = 0.83; P < 0.001) while no relationship existed between PAH levels and population (r2 = 0.01; P > 0.1). Atmospheric deposition of PAHs at different regions in Hungary may be due to incomplete combustion of fuel. The total concentrations of PAHs were compared to the PAH levels in vegetation samples collected from different regions around the world. The highest PAHs concentrations accumulated were found in Hypnum cupressiforme than other vegetation species. A greater affinity for PAH compounds by Hypnum cupressiforme than other moss species probably caused larger amounts of accumulation. A relationship between accumulations of PAH compounds in Hypnum cupressiforme and octanol-air partition coefficients was obtained and is briefly discussed. 相似文献
68.
We consider the problem of allocating the cost of an optimal traveling salesman tour in a fair way among the nodes visited; in particular, we focus on the case where the distance matrix of the underlying TSP problem satisfies the triangle inequality. We thereby use the model of TSP games in the sense of cooperative game theory. We give examples showing that the core of such games may be empty, even for the case of Euclidean distances. On the positive, we develop an LP-based allocation rule guaranteeing that no coalition pays more than times its own cost, where is the ratio between the optimal TSP-tour and the optimal value of its Held-Karp relaxation, which is also known as the solution over the subtour polytope. A well-known conjecture states that4/3. We also exhibit examples showing that this ratio cannot be improved below 4/3.Parts of this work were done while the author was visiting at RUTCOR, Rutgers University, supported by SFB 303 (Deutsche Forschungsgemeinschaft). 相似文献
69.
Isenberg P. Carpendale S. Bezerianos A. Henry N. Fekete J.-D. 《Computer Graphics and Applications, IEEE》2009,29(5):44-57
In this paper, the authors retrofitted a version of NodeTrix, a single-user graph visualization environment based on the InfoVis toolkit, to support multiple independent mice. The resulting low-cost environment was called CoCoNutTrix (Colocated Collaborative NodeTrix). Then, it was assessed how analysts viewed CoCoNutTrix and whether it effectively supported collaborative data analysis among domain experts using real data sets for social-network analysis. Our goal is to refine and expand our knowledge about retrofitting and hence designing colocated collaborative- visualization systems. 相似文献
70.
Michael A. Bender David P. Bunde Erik D. Demaine Sándor P. Fekete Vitus J. Leung Henk Meijer Cynthia A. Phillips 《Algorithmica》2008,50(2):279-298
We give processor-allocation algorithms for grid architectures, where the objective is to select processors from a set of
available processors to minimize the average number of communication hops.
The associated clustering problem is as follows: Given n points in ℜ
d
, find a size-k subset with minimum average pairwise L
1 distance. We present a natural approximation algorithm and show that it is a
-approximation for two-dimensional grids; in d dimensions, the approximation guarantee is
, which is tight. We also give a polynomial-time approximation scheme (PTAS) for constant dimension d, and we report on experimental results. 相似文献