142 research outputs found
An application of eye movement parameters collected from mass market devices for the estimation of a text comprehension
The growing interest in evaluating the reader's comprehension leads to the search for new methods that allow such estimation in real-time (or pseudo-real-time). This can be used for more effective educational processes and to adopt textual content for various purposes. The present study used the Oken Reader eye-tracking application (60 Hz) for mass-market devices to assess reading comprehension processes. Twenty-three (23) respondents aged between 19 and 31 (mean = 24. 5, SE = 1. 4, 65% female) participated in the study. The mean, mu, and sigma parameters differed significantly depending on the level of text comprehension. This result indicates the possibility of using mass-market devices with eye-tracking technology to assess comprehension in reading. Furthermore, the study's results confirm the possibility of searching the correlations between physiological indicators such as eye movements and comprehension
Therapeutic use of VEGF-C and CCBE1
The present invention relates to therapeutic methods, us- es and compositions comprising CCBE1 and VEGF-C for treating disorders and conditions involving impaired lymphatic system, particularly lymphedema
Effect of sintering duration on structure and properties of Ni-Al metal-intermetallic composites produced by SPS
The fabrication of Ni-Al based metal-intermetallic layered (MIL) composites is one of the actively developing directions in the production of materials for aircraft and space industries. Alternating hard intermetallic layers with ductile metal layers provides a unique combination of mechanical properties. In this study, metal-intermetallic layered composites consisting of Ni and nickel aluminides were fabricated using spark plasma sintering (SPS) of Ni and Al foils 100 and 25 μm in thickness, respectively. Samples sintered at 1100 °C for 0.5, 3, and 8 min were obtained. The purpose of this study was to fabricate Ni-Al MIL composites with increased strength properties using SPS technique and to investigate the effect of sintering duration on structure and properties. The structure of the samples sintered for 0.5 min consisted of Ni layers and intermetallic layers containing the sublayers with stoichiometric and Ni-rich B2 NiAl, L10 twinned martensite NiAl. The tensile strength of such composites was 485 MPa. The intermetallic layers in the sample sintered for 3 min have more Ni-rich NiAl, martensite NiAl, and Ni3Al phases, which promoted to an increase in tensile strength to 575 MPa. The sample sintered for 8 min consisted of Ni and a solid solution of Al in Ni and showed the highest tensile strength, 610 MPa, due to solid solution hardening in the interlayers. The samples did not break when applying bending load, which is the evidence of the good reliability and durability of the composites
Age-Dependent Remarkable Regenerative Potential of the Dentate Gyrus Provided by Intrinsic Stem Cells
Multiple insults to the brain lead to neuronal cell death, thus raising the question to what extent can lost neurons be replenished by adult neurogenesis. Here we focused on the hippocampus and especially the dentate gyrus (DG), a vulnerable brain region and one of the two sites where adult neuronal stem cells (NSCs) reside. While adult hippocampal neurogenesis was extensively studied with regard to its contribution to cognitive enhancement, we focused on their underestimated capability to repair a massively injured, nonfunctional DG. To address this issue, we inflicted substantial DG-specific damage in mice of either sex either by diphtheria toxin-based ablation of >50% of mature DG granule cells (GCs) or by prolonged brain-specific VEGF overexpression culminating in extensive, highly selective loss of DG GCs (thereby also reinforcing the notion of selective DG vulnerability). The neurogenic system promoted effective regeneration by increasing NSCs proliferation/survival rates, restoring a nearly original DG mass, promoting proper rewiring of regenerated neurons to their afferent and efferent partners, and regaining of lost spatial memory. Notably, concomitantly with the natural age-related decline in the levels of neurogenesis, the regenerative capacity of the hippocampus also subsided with age. The study thus revealed an unappreciated regenerative potential of the young DG and suggests hippocampal NSCs as a critical reservoir enabling recovery from catastrophic DG damage.Peer reviewe
Effects of detector efficiency mismatch on security of quantum cryptosystems
We suggest a type of attack on quantum cryptosystems that exploits variations
in detector efficiency as a function of a control parameter accessible to an
eavesdropper. With gated single-photon detectors, this control parameter can be
the timing of the incoming pulse. When the eavesdropper sends short pulses
using the appropriate timing so that the two gated detectors in Bob's setup
have different efficiencies, the security of quantum key distribution can be
compromised. Specifically, we show for the Bennett-Brassard 1984 (BB84)
protocol that if the efficiency mismatch between 0 and 1 detectors for some
value of the control parameter gets large enough (roughly 15:1 or larger), Eve
can construct a successful faked-states attack causing a quantum bit error rate
lower than 11%. We also derive a general security bound as a function of the
detector sensitivity mismatch for the BB84 protocol. Experimental data for two
different detectors are presented, and protection measures against this attack
are discussed.Comment: v3: identical to the journal version. However, after publication we
have discovered that Eq. 11 is incorrect: the available bit rate after
privacy amplification is reduced even in the case (QBER)=0 [see Quant. Inf.
Comp. 7, 73 (2007)
Domestic scientific media discourse in academic journals: Structural analysis
The article presents the results of meta-research devoted to the study of domestic scientific discourse in academic journals in the field of journalism and mass communications. The empirical basis of the study was formed from an array of articles published in journals indexed in the RSCI and Web of Science Core Collection (WoS CC) databases in the period of 2015–2021. The authors analyzed more than 18 thousand articles, determined the quantitative indicators of published materials; marked the most significant research centers engaged in academic research in the field of journalism and mass communications (Lomonosov Moscow State University, Saint Petersburg State University); and reviewed the largest number of publications (Elena Vartanova, Olga Smirnova, Andrey Vyrkovsky). The most relevant thematic clusters in domestic media studies were also identified. For journals indexed in the RSCI, these are the digital media environment, the history of Russian journalism and literature, and media linguistics. For journals indexed by WoS, this is the digital media environment, as well as political topics, media linguistics and media theory
Sequestering by global symmetries in Calabi-Yau string models
We study the possibility of realizing an effective sequestering between
visible and hidden sectors in generic heterotic string models, generalizing
previous work on orbifold constructions to smooth Calabi-Yau compactifications.
In these theories, genuine sequestering is spoiled by interactions mixing
chiral multiplets of the two sectors in the effective Kahler potential. These
effective interactions however have a specific current-current-like structure
and can be interpreted from an M-theory viewpoint as coming from the exchange
of heavy vector multiplets. One may then attempt to inhibit the emergence of
generic soft scalar masses in the visible sector by postulating a suitable
global symmetry in the dynamics of the hidden sector. This mechanism is however
not straightforward to implement, because the structure of the effective
contact terms and the possible global symmetries is a priori model dependent.
To assess whether there is any robust and generic option, we study the full
dependence of the Kahler potential on the moduli and the matter fields. This is
well known for orbifold models, where it always leads to a symmetric scalar
manifold, but much less understood for Calabi-Yau models, where it generically
leads to a non-symmetric scalar manifold. We then examine the possibility of an
effective sequestering by global symmetries, and argue that whereas for
orbifold models this can be put at work rather naturally, for Calabi-Yau models
it can only be implemented in rather peculiar circumstances.Comment: 47 pages, no figure
Findings to the flora of Russia and adjacent countries: New national and regional vascular plant records, 4
With this paper we continue a new annual series, the main purpose of which is to make significant floristic findings from Russia and neighboring countries more visible in Russia and abroad. In total, this paper presents new records for 48 vascular plant species from 6 Eurasian countries, obtained during field explorations, as well as during taxonomic revisions of herbarium materials. For the first time, a new locality of Leontopodium leiolepis is recorded for Russia, Rheum uzengukuushi for China, Rorippa prolifera for Lithuania, Lappula marginata for Kyrgyzstan and Tajikistan, Anthriscus caucalis, Chenopodium ficifolium, Euphorbia prostrata for Uzbekistan, Adonis × hybrida, Potamogeton × franconicus, Solidago × niederederi for the Asian part of Russia, Echinochloa esculenta, Poa jamalinensis, Puccinellia poecilantha for Siberia, Potentilla intermedia for the Caucasus, Rhynchospora alba for the Russian part of Altai, Poa sphondylodes, Veronica beccabunga for Eastern Siberia, Asclepias syriaca for the Republic of Altai, Chimaphila umbellata, Orobanche korshinskyi, Veronica scutellata for the Republic of Buryatia, Cirsium alatum, Thalictrum simplex for the Republic of Crimea, Thymus rariflorus, Th. terekensis for the Republic of Ingushetia, Berberis thunbergii, Crataegus maximowiczii, Prunus serotina for the Republic of Mordovia, Oenothera villosa for the Republic of Tatarstan, Astragalus sulcatus, Galium mollugo for the Republic of Tyva, Phragmites altissimus for the Chelyabinsk Region, Senecio dubitabilis for the Magadan Region, Asclepias syriaca, Galatella villosa, Potentilla recta for the Novosibirsk Region, Dodartia orientalis for the Omsk Region, Viola hultenii for the Sakhalin Region, Phragmites tzvelevii for the Samara Region and the Middle Volga, Jacobaea ferganensis for the Samara Region, Carex media, Impatiens parviflora for the Tyumen Region. There are some more findings which are not new for the region but they contribute significantly to the understanding of species distribution
Mildly sequestered supergravity models and their realization in string theory
We elaborate on the idea that five-dimensional models where sequestering is
spoiled due to contact interactions induced by vector multiplets may still be
mildly sequestered if a global version of the gauge symmetry associated to the
latter survives in the hidden sector. Interestingly, it has been argued that
although in such a situation non-trivial current-current contact interactions
are induced by the heavy vector modes, these do not induce soft scalar masses,
as a consequence of the global symmetry. We perform a detailed study of how
this hybrid mechanism can be implemented in supergravity and string models,
focusing on the prototypical case of heterotic M-theory orbifolds. We emphasize
that in general the mechanism works only up to subleading effects suppressed by
the ratio between the global symmetry breaking scale in the hidden sector and
the vector mass scale or the Planck scale. We also argue that this mild
sequestering mechanism allows to rehabilitate the scenario of dilaton
domination of supersymmetry breaking, which is incompatible with dilaton
stabilization in its original version, by exploiting the fact that hidden brane
fields do contribute to the cosmological constant but not to soft terms, thanks
to the global symmetry.Comment: 31 pages, LaTex, no figure
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