3,280 research outputs found

    Casimir operators of centrally extended l-conformal Galilei algebra

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    The full set of Casimir elements of the centrally extended l-conformal Galilei algebra is found in simple and tractable form.Comment: 5 page

    WIMP astronomy and particle physics with liquid-noble and cryogenic direct-detection experiments

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    Once weakly-interacting massive particles (WIMPs) are unambiguously detected in direct-detection experiments, the challenge will be to determine what one may infer from the data. Here, I examine the prospects for reconstructing the local speed distribution of WIMPs in addition to WIMP particle-physics properties (mass, cross sections) from next-generation cryogenic and liquid-noble direct-detection experiments. I find that the common method of fixing the form of the velocity distribution when estimating constraints on WIMP mass and cross sections means losing out on the information on the speed distribution contained in the data and may lead to biases in the inferred values of the particle-physics parameters. I show that using a more general, empirical form of the speed distribution can lead to good constraints on the speed distribution. Moreover, one can use Bayesian model-selection criteria to determine if a theoretically-inspired functional form for the speed distribution (such as a Maxwell-Boltzmann distribution) fits better than an empirical model. The shape of the degeneracy between WIMP mass and cross sections and their offset from the true values of those parameters depends on the hypothesis for the speed distribution, which has significant implications for consistency checks between direct-detection and collider data. In addition, I find that the uncertainties on theoretical parameters depends sensitively on the upper end of the energy range used for WIMP searches. Better constraints on the WIMP particle-physics parameters and speed distribution are obtained if the WIMP search is extended to higher energy (~ 1 MeV).Comment: 25 pages, 27 figures, matches published versio

    ΠœΠΎΠ΄Π΅Π»ΠΈΡ€ΠΎΠ²Π°Π½ΠΈΠ΅ условий протСкания Ρ€Π΅Π°ΠΊΡ†ΠΈΠΈ для составов Π½Π° основС оксида ΠΆΠ΅Π»Π΅Π·Π° с ΠΏΠΎΠΌΠΎΡ‰ΡŒΡŽΠΏΡ€ΠΎΠ³Ρ€Π°ΠΌΠΌΠ½ΠΎΠ³ΠΎ комплСкса Астра - 4

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    Π Π°Π±ΠΎΡ‚Π° посвящСна исслСдованию установлСниС возмоТности протСкания Ρ€Π΅Π°ΠΊΡ†ΠΈΠΈ элСмСнтов Π½Π° основС оксида ΠΆΠ΅Π»Π΅Π·Π°. По Ρ€Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚Π°ΠΌ модСлирования Π² ΠΏΡ€ΠΎΠ³Ρ€Π°ΠΌΠΌΠ½ΠΎΠΌ комплСксС Астра - 4 ΠΏΠΎΠ»ΡƒΡ‡Π΅Π½Ρ‹ ΠΏΠΎΠΊΠ°Π·Π°Ρ‚Π΅Π»ΠΈ, ΠΏΡ€ΠΈ ΠΊΠΎΡ‚ΠΎΡ€Ρ‹Ρ… Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎ ΠΏΡ€ΠΎΡ‚Π΅ΠΊΠ°Π½ΠΈΠΈ Ρ€Π΅Π°ΠΊΡ†ΠΈΠΈ Fe2O3 + Al+ Cr= Al2O3+Fe+ Cr Π° Ρ‚Π°ΠΊΠΆΠ΅ Π΄Π°Π½Π½Ρ‹Π΅ Ρ‚Π΅ΠΌΠΏΠ΅Ρ€Π°Ρ‚ΡƒΡ€Ρ‹ (2430 К) ΠΈ наибольшСй Π²Π½ΡƒΡ‚Ρ€Π΅Π½Π½Π΅ΠΉ энСргиСй S (4076,2 ΠΊΠ”ΠΆ/(ΠΊΠ³*К)).The study was devoted to establishing the possibility of reaction elements on the basis of iron oxide. The results of the simulations in the software package Astra - 4 the obtained values allow the reaction Fe2O3 + Al+ Cr= Al2O3+Fe+ Cr and the temperature data (2430) and the greatest internal energy S (4076,2 kJ/(kg*K))

    Men, Women, Microblogging: Where Do We Stand?

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    With millions of users worldwide, microblogging has developed into a powerful tool for interaction and information dissemination. While both men and women readily use this technology, there are significant differences in how they embrace it. Understanding these differences is important to ensure gender parity, provide advertisers with actionable insights on the marketing potential of both groups, and to inform current theories on how microblogging affordances shape gender roles. So far, existing research has not provided a unified framework for such analysis, with gender insights scattered across multiple studies. To fill this gap, our study conducts a comprehensive meta-review of existing research. We find that current discourse offers a solid body of knowledge on gender differences in adoption, shared content, stylistic presentation, and a rather convoluted picture of female and male interaction. Together, our structured findings offer a deeper insight into the underlying dynamics of gender differences in microblogging

    Cued repetition of self-directed behaviors in macaques (Macaca nemestrina)

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    Two macaques were trained to perform three self-directed behaviors on signal, and to repeat behaviors after a ‘repeat’ signal. The cognitive processes underlying the monkeys’ repeat performance were evaluated using multiple repetitions of the repeat signal, extended delay periods between target behavior and repeat signal, and by transferring the repeat signal to novel behaviors. The monkeys appear to have used representations of their own past behaviors as a basis for repetition performance, but they mostly failed to correctly repeat target behaviors after extended delays and during transfer tasks. Implications for episodic memory abilities are discussed

    Development of a Fully Synthetic Corneal Stromal Construct via Supramolecular Hydrogel Engineering

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    Recent advances in the field of ophthalmology show great potential in the design of bioengineered constructs to mimic the corneal stroma. Hydrogels based on synthetic supramolecular polymers, are attractive synthetic mimics of the natural highly hydrated corneal stroma. Here, a fully synthetic corneal stromal construct is developed via engineering of an injectable supramolecular hydrogel based on ureido-pyrimidinone (UPy) moieties. The hydrogel displays a dynamic and tunable behavior, which allows for control of biochemical and mechanical cues. Two hydrogels are developed, a fully synthetic hydrogel functionalized with a bioactive cyclic arginine-glycine-aspartate UPy (UPy-cRGD) additive, and a hybrid hydrogel based on UPy-moieties mixed with collagen type I fibers. Both hydrogels supported cell encapsulation and associated cellular deposition of extracellular matrix (ECM) proteins after 21 days. Excitingly, the hydrogels support the activation of isolated primary keratocytes into stromal fibroblasts as well as the differentiation toward more quiescent corneal stromal keratocytes, demonstrated by their characteristic long dendritic protrusions and a substantially diminished cytokine secretion. Furthermore, cells survive shear stresses during an injectability test. Together, these findings highlight the development of an injectable supramolecular hydrogel as a synthetic corneal stromal microenvironment able to host primary keratocytes.</p
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