Low Mach-number collisionless electrostatic shocks and associated ion acceleration

The existence and properties of low Mach-number ($M \gtrsim 1$) electrostatic collisionless shocks are investigated with a semi-analytical solution for the shock structure. We show that the properties of the shock obtained in the semi-analytical model can be well reproduced in fully kinetic Eulerian Vlasov-Poisson simulations, where the shock is generated by the decay of an initial density discontinuity. Using this semi-analytical model, we study the effect of electron-to-ion temperature ratio and presence of impurities on both the maximum shock potential and Mach number. We find that even a small amount of impurities can influence the shock properties significantly, including the reflected light ion fraction, which can change several orders of magnitude. Electrostatic shocks in heavy ion plasmas reflect most of the hydrogen impurity ions.Comment: In Plasma Physics and Controlled Fusio

Enhanced transmission versus localization of a light pulse by a subwavelength metal slit: Can the pulse have both characteristics?

The existence of resonant enhanced transmission and collimation of light waves by subwavelength slits in metal films [for example, see T.W. Ebbesen et al., Nature (London) 391, 667 (1998) and H.J. Lezec et al., Science, 297, 820 (2002)] leads to the basic question: Can a light be enhanced and simultaneously localized in space and time by a subwavelength slit? To address this question, the spatial distribution of the energy flux of an ultrashort (femtosecond) wave-packet diffracted by a subwavelength (nanometer-size) slit was analyzed by using the conventional approach based on the Neerhoff and Mur solution of Maxwell's equations. The results show that a light can be enhanced by orders of magnitude and simultaneously localized in the near-field diffraction zone at the nm- and fs-scales. Possible applications in nanophotonics are discussed.Comment: 5 figure

A Magyarországon tanuló külföldi egyetemi hallgatók turisztikai fogyasztási szokásainak elsődleges elemzése = The primary analysis of the tourism consumption habits of the international students studying in Hungary

Jelen tanulmány felméri és összegzi azon kutatási eredményeket, amelyek a Magyarországon tanuló nemzetközi diákok és az őket meglátogatók turisztikai fogyasztási szokásaira vonatkoznak. A kérdőíves megkeresésekkel kivitelezett kutatással, a hazánkban tanuló nemzetközi hallgatók magyarországi turisztikai szokásaira vonatkozó kérdéseken keresztül azt kívántuk feltárni, hogy ez a szegmens milyen mértékben jelenik meg a hazai turisztikai folyamatokban, és milyen gazdasági hatással bír. A tanulmány eredményeinek közlése tekintetében kijelenthető, hogy hazánkban hasonló jellegű kutatás még nem zajlott le, így a nemzetközi hallgatókhoz köthető turizmus társadalmi-gazdasági és turisztikai folyamatokban betöltött szerepének vizsgálata tudományos nóvum Magyarországon. Elsődleges eredményeink igazolják, hogy a szegmens aktívan részt vesz a hazai turisztikai folyamatokban, így, mivel ezen fogyasztói csoport pontos megismerése még csak most kezdődött el, javasoljuk egy vonatkozó országos, illetve az egyes kiemelt egyetemi városokat célzó turizmusmarketing stratégia kidolgozását. = This study surveys and summarizes the research results related to the tourism consumption habits of international students studying in Hungary together with their visitors. With questions focusing on the travel habits of the international students, the research, carried out by questionnaire survey, was intended to show the scale of this segment in Hungarian tourism and the economic impact also. In relation to the publication of the results, we can confirm that no similar research has been carried out yet in Hungary, and so the analysis of the role of international students in the socialeconomic and touristic processes is a scientific novelty in Hungary. Our primary results show that the segment plays an active part in domestic tourism, and so, since a clear recognition of this significant target group has recently emerged. The authors recommend the elaboration of a related tourism marketing strategy on national and university city levels

Összefüggések a talaj Arany-féle kötöttségi száma, higroszkópossága és humusztartalma között

Black and white 3x4 Nitrate/Acetate Negativehttps://digitalmaine.com/arc_george_french_photos_a34/1510/thumbnail.jp

Short communication: Goat colostrum quality: Litter size and lactation number effects

The quality of colostrum of Murciano-Granadina goats was studied to establish the transition period and the time when milk can be marketed. Forty-three dairy goats were used: 19 primiparous (15 single births; 4 multiple births) and 24 multiparous (10 single births; 14 multiple births). Samples were collected every 12 h during the first week postpartum. Physicochemical parameters and somatic cell count were determined. Analysis of variance with repeated measures was used to study the effect of different factors: postpartum time, litter size, lactation number, their interactions, and production level on colostrum. Postpartum time had a significant effect on all parameters studied, which decreased along the first week of lactation, whereas lactose, pH, and conductivity increased. Based on these results, colostrum secretion takes place until 36 h postpartum (hpp). In relation to other factors of variation studied, the lactation number influenced most colostrum components, whereas the litter size only affected the pH value, protein and lactose content. The production level influenced only the protein and dry matter contents, with an inverse relationship. Milk produced during the period between 36 and 96 hpp is considered transition milk, which should not be commercialized. Milk collected after 4 d postpartum (96 hpp) could be marketed, ensuring that its composition does not present a risk in the dairy industry.This work was part of the AGL-2009-11524 Project funded by the Spanish Ministry of Science and Innovation (Madrid, Spain). The authors are grateful to ZEU-Inmunotec (Zaragoza, Spain) for their support.Romero Rueda, T.; Beltrán Martínez, MC.; Rodríguez Garcia, M.; Marti-De Olives A.; Molina Pons, MP. (2013). Short communication: Goat colostrum quality: Litter size and lactation number effects. Journal of Dairy Science. 96(12):7526-7531. https://doi.org/10.3168/jds.2013-6900S75267531961

Speech-centric multimodal interaction for easy-to-access online services: A personal life assistant for the elderly

The PaeLife project is a European industry-academia collaboration whose goal is to provide the elderly with easy access to online services that make their life easier and encourage their continued participation in the society. To reach this goal, the project partners are developing a multimodal virtual personal life assistant (PLA) offering a wide range of services from weather information to social networking. This paper presents the multimodal architecture of the PLA, the services provided by the PLA, and the work done in the area of speech input and output modalities, which play a key role in the application.info:eu-repo/semantics/publishedVersio

Speech-centric multimodal interaction for easy-to-access online services: A personal life assistant for the elderly

The PaeLife project is a European industry-academia collaboration whose goal is to provide the elderly with easy access to online services that make their life easier and encourage their continued participation in the society. To reach this goal, the project partners are developing a multimodal virtual personal life assistant (PLA) offering a wide range of services from weather information to social networking. This paper presents the multimodal architecture of the PLA, the services provided by the PLA, and the work done in the area of speech input and output modalities, which play a key role in the application.info:eu-repo/semantics/publishedVersio

Micro droplet formation towards continuous nanoparticles synthesis

In this paper, micro droplets are generated in a microfluidic focusing contactor and then they move sequentially in a free-flowing mode (no wall contact). For this purpose, two different micro-flow glass devices (hydrophobic and hydrophilic) were used. During the study, the influence of the flow rate of the water phase and the oil phase on the droplet size and size distribution was investigated. Moreover, the influence of the oil phase viscosity on the droplet size was analyzed. It was found that the size and size distribution of the droplets can be controlled simply by the aqueous phase flow rate. Additionally, 2D simulations to determine the droplet size were performed and compared with the experiment.Marek Wojnicki, Magdalena Luty-Błocho, Volker Hessel, Edit Csapó, Ditta Ungor and Krzysztof Fitzne

mtDNA data reveal disparate population structures and High Arctic colonization patterns in three intertidal invertebrates with contrasting life history traits

Introduction: Post-glacial climate variation is known to have influenced the distribution of marine species in the North Atlantic. In particular, the Atlantic side of the Arctic has experienced strong fluctuations in both atmospheric and sea surface temperature, as well as seasonal ice coverage since the last glacial maximum (LGM). Here, we aim to unveil the phylogeography and historical demography of three rocky intertidal marine invertebrates showing a trans-Atlantic distribution and presently inhabiting the Arctic: Gammarus oceanicus, Littorina saxatilis and Semibalanus balanoides. Methods: We used a large amount of mitochondrial DNA barcode data, both newly-obtained and stored in public databases. We performed phylogeographic and demographic analyses on 1119 G. oceanicus, 205 L. saxatilis, and 884 S. balanoides sequences. Results: Our results show that all three of these boreal species have expanded their effective population sizes in the high Arctic Svalbard Archipelago since the LGM. Analyses investigating the origin of all these populations point to the eastern Atlantic. Discussion: Based on our results we conclude that the expansion of these boreal species to the Arctic possibly happened during an earlier warm cycle of the Holocene era, and is probably not the result of the recent ‘Atlantification’ of the Arctic. We also discuss the effects of dispersal potential on population structure as an important aspect of comparative biogeographical studies