45 research outputs found

    The influence of Pichia killer toxins on the wine spoilage yeasts

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    Killer yeasts are able to produce toxins that antagonize the growth of susceptible yeasts cells of the same species or the ones that are related to them. Killer strains are resistant to their own toxins but can be sensitive to killer proteins of other yeasts. The killer proteins of Pichia spp. are known for its broad spectrum of antifungal activity including pathogens such as Candida albicans. The aim of the study was to investigate the potential of the partly purified killer toxins to inhibit the growth of selected yeast strains which can contribute to wine spoilage. Three Pichia killer yeast strains (CBS 1982, CBS 5759, CBS 7373) were used in the study. The killer protein secreted by Pichia anomala CBS 1982 was characterized by the highest antifungal activity. The most pronounced effect of the reduction of cell proliferation by killer toxin preparations was found after 2 and 20 h cultivation. Among the 13 tested strains, all Pichia killer toxin preparations inhibited the growth of Rhodotorula graminis Rg, Rhodotorula mucilaginosa Rm and Schizosaccharomyces pombe DSM 70576. Killer toxins produced by Pichia anomala CBS 1982 (K8) and CBS 5759 (K4) limited the growth of Candida pulcherrima K5 and Hanseniaspora guillermondii DSM 3432 after 2, 20 and 168 h of incubation. A significant reduction of Debaryomyces hansenii DSM 3428 biomass was observed in medium with the addition of one toxin preparation (Pichia anomala CBS 1982). The growth limitation of Candida glabrata DSM 6425, Hanseniaspora uvarum DSM 2768, Metchnikowia pulcherrima DSM 70321 and Cryptococcus laurentii DSM 70766 was noticed only after 2 hours cultivation in presence of killer protein preparations. The killer toxins could be used in the food industry as selective tools to control infections during the fermentation of wine and improve the quality of the final product

    Path Loss and Shadowing Modeling for Vehicle-to-Vehicle Communications in Terrestrial TV Band

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    Vehicle platooning is considered as one of the key use cases for vehicle-to-vehicle (V2V) communications. However, its benefits can be realized only with highly reliable wireless transmission. As the 5.9GHz frequency band used for V2V suffers from high congestion, in this paper, we consider the use of the terrestrial TV frequencies for intra-platoon communications. In order to be able to evaluate the potential of the new bands fully, propagation models for V2V communications at such frequencies are needed. Therefore, this paper reports new V2V propagation measurements and their modeling results. Particularly, we propose a Double Slope Double Shadowing model as the most accurate one, based on a comparison of various models using the Bayesian Information Criteria. We also investigate the space-time autocorrelation properties of the shadowing, which turned out to be dependent on the speed of vehicles. The proposed path loss and shadowing model differs from the ones proposed for the 5.9GHz band. Mostly, in favor of the TV band, as shown by, e.g., no statistically significant impact of a blocking car

    MIMO-OFDM Crystallized Rate Regions

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    In this paper, we introduce the generalization of the con- cept of crystallized rate regions for MIMO-OFDM trans- mission. The extension from the OFDM and MIMO case to MIMO-OFDM scenario of the time-sharing convex hull of achievable rates is discussed and a new definition of the cost function for the rate region game is derived. Based on the new game definition, the simulation results for the MIMO-OFDM case are presented

    Crystallized Rate Regions for MIMO Transmission

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    International audienceWhen considering the multiuser SISO interference channel, the allowable rate region is not convex and the maximization of the aggregated rate of all the users by the means of transmission power control becomes inefficient. Hence, a concept of the crystallized rate regions has been proposed, where the time-sharing approach is considered to maximize the sumrate.In this paper, we extend the concept of crystallized rate regions from the simple SISO interference channel case to the MIMO/OFDM interference channel. As a first step, we extend the time-sharing convex hull from the SISO to the MIMO channel case. We provide a non-cooperative game-theoretical approach to study the achievable rate regions, and consider the Vickrey-Clarke-Groves (VCG) mechanism design with a novel cost function. Within this analysis, we also investigate the case of OFDM channels, which can be treated as the special case of MIMO channels when the channel transfer matrices are diagonal. In the second step, we adopt the concept of correlated equilibrium into the case of two-user MIMO/OFDM, and we introduce a regret-matching learning algorithm for the system to converge to the equilibrium state. Moreover, we formulate the linear programming problem to find the aggregated rate of all users and solve it using the Simplex method. Finally, numerical results are provided to confirm our theoretical claims and show the improvement provided by this approach

    Why Is White Noise Not Enough? Using Radio Front-End Models While Designing 6G PHY, Journal of Telecommunications and Information Technology, 2023, nr 2

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    Each subsequent generation of wireless standards imposes stricter spectral and energy efficiency demands. So far, layered wireless transceiver architectures have been used, allowing for instance to separate channel decoding algorithms from the front-end design. Such an approach may need to be reconsidered in the upcoming 6G era. Especially hardware-originated distortions have to be taken into account while designing other layer algorithms, as high throughput and energy efficiency requirements will push these devices to their limits, revealing their non-linear characteristics. In such a context, this paper will shed some light on the new degrees of freedom enjoyed while cross-layer designing as well as controlling multicarrier and multiantenna transceivers in 6G systems

    Resource and Mobility Management in the Network Layer of 5G Cellular Ultra-Dense Networks

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    © 2017 IEEE. Personal use of this material is permitted. Permissíon from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertisíng or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.[EN] The provision of very high capacity is one of the big challenges of the 5G cellular technology. This challenge will not be met using traditional approaches like increasing spectral efficiency and bandwidth, as witnessed in previous technology generations. Cell densification will play a major role thanks to its ability to increase the spatial reuse of the available resources. However, this solution is accompanied by some additional management challenges. In this article, we analyze and present the most promising solutions identified in the METIS project for the most relevant network layer challenges of cell densification: resource, interference and mobility management.This work was performed in the framework of the FP7 project ICT-317669 METIS, which is partly funded by the European Union. The authors would like to acknowledge the contributions of their colleagues in METIS, although the views expressed are those of the authors and do not necessarily represent the project.Calabuig Soler, D.; Barmpounakis, S.; Giménez Colás, S.; Kousaridas, A.; Lakshmana, TR.; Lorca, J.; Lunden, P.... (2017). Resource and Mobility Management in the Network Layer of 5G Cellular Ultra-Dense Networks. IEEE Communications Magazine. 55(6):162-169. https://doi.org/10.1109/MCOM.2017.1600293S16216955

    DR9.3 Final report of the JRRM and ASM activities

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    Deliverable del projecte europeu NEWCOM++This deliverable provides the final report with the summary of the activities carried out in NEWCOM++ WPR9, with a particular focus on those obtained during the last year. They address on the one hand RRM and JRRM strategies in heterogeneous scenarios and, on the other hand, spectrum management and opportunistic spectrum access to achieve an efficient spectrum usage. Main outcomes of the workpackage as well as integration indicators are also summarised.Postprint (published version

    Qualitative Parameters of the Colonic Flora in Patients with HNF1A-MODY Are Different from Those Observed in Type 2 Diabetes Mellitus

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    Background. Type 2 diabetes mellitus (T2DM) is determined by genetic and environmental factors. There have been many studies on the relationship between the composition of the gastrointestinal bacterial flora, T2DM, and obesity. There are no data, however, on the gut microbiome structure in monogenic forms of the disease including Maturity Onset Diabetes of the Young (MODY). Methods. The aim of the investigation was to compare the qualitative parameters of the colonic flora in patients with HNF1A-MODY and T2DM and healthy individuals. 16S sequencing of bacterial DNA isolated from the collected fecal samples using the MiSeq platform was performed. Results. There were significant between-group differences in the bacterial profile. At the phylum level, the amount of Proteobacteria was higher ( = 0.0006) and the amount of Bacteroidetes was lower ( = 0.0005) in T2DM group in comparison to the control group. In HNF1A-MODY group, the frequency of Bacteroidetes was lower than in the control group ( = 0.0143). At the order level, Turicibacterales was more abundant in HNF1A-MODY group than in T2DM group. Conclusions. It appears that there are differences in the gut microbiome composition between patients with HNF1A-MODY and type 2 diabetes. Further investigation on this matter should be conducted

    THE COMPOSITION OF SELECTED VOLATILE COMPOUNDS IN FERMENTED MASHES OBTAINED FROM DIFFERENT VARIETIES OF PLUMS

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    Abstract: The aim of this study was to determine the influence of plum variety (Wegierka Dabrowiecka, Wegierka Zwykla, Cacanska Lepotica, Stanley) on the volatile composition of spontaneously fermented plum mashes which after distillation could be used for plum brandies production. The GC-SPME was used for selected volatile components analysis. The variety of plums strongly influenced the volatile composition of obtained fermented plum mashes. The highest concentration of ethanol, acetaldehyde and propanol was found in the Wegierka Dabrowiecka mashes, while ethyl acetate and acetic acid were present in increased amount in Wegierka Zwykla mashes. Other two mashes -Cacanska Lepotica and Stanley were characterized by the highest levels of isobutanol and amyl alcohols, and methanol, butanol, hexanol and 2-phenylalcohol, respectively
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