3,280 research outputs found
Casimir operators of centrally extended l-conformal Galilei algebra
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
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
ΠΠΎΠ΄Π΅Π»ΠΈΡΠΎΠ²Π°Π½ΠΈΠ΅ ΡΡΠ»ΠΎΠ²ΠΈΠΉ ΠΏΡΠΎΡΠ΅ΠΊΠ°Π½ΠΈΡ ΡΠ΅Π°ΠΊΡΠΈΠΈ Π΄Π»Ρ ΡΠΎΡΡΠ°Π²ΠΎΠ² Π½Π° ΠΎΡΠ½ΠΎΠ²Π΅ ΠΎΠΊΡΠΈΠ΄Π° ΠΆΠ΅Π»Π΅Π·Π° Ρ ΠΏΠΎΠΌΠΎΡΡΡΠΏΡΠΎΠ³ΡΠ°ΠΌΠΌΠ½ΠΎΠ³ΠΎ ΠΊΠΎΠΌΠΏΠ»Π΅ΠΊΡΠ° ΠΡΡΡΠ° - 4
Π Π°Π±ΠΎΡΠ° ΠΏΠΎΡΠ²ΡΡΠ΅Π½Π° ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ ΡΡΡΠ°Π½ΠΎΠ²Π»Π΅Π½ΠΈΠ΅ Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎΡΡΠΈ ΠΏΡΠΎΡΠ΅ΠΊΠ°Π½ΠΈΡ ΡΠ΅Π°ΠΊΡΠΈΠΈ ΡΠ»Π΅ΠΌΠ΅Π½ΡΠΎΠ² Π½Π° ΠΎΡΠ½ΠΎΠ²Π΅ ΠΎΠΊΡΠΈΠ΄Π° ΠΆΠ΅Π»Π΅Π·Π°. ΠΠΎ ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΠ°ΠΌ ΠΌΠΎΠ΄Π΅Π»ΠΈΡΠΎΠ²Π°Π½ΠΈΡ Π² ΠΏΡΠΎΠ³ΡΠ°ΠΌΠΌΠ½ΠΎΠΌ ΠΊΠΎΠΌΠΏΠ»Π΅ΠΊΡΠ΅ ΠΡΡΡΠ° - 4 ΠΏΠΎΠ»ΡΡΠ΅Π½Ρ ΠΏΠΎΠΊΠ°Π·Π°ΡΠ΅Π»ΠΈ, ΠΏΡΠΈ ΠΊΠΎΡΠΎΡΡΡ
Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎ ΠΏΡΠΎΡΠ΅ΠΊΠ°Π½ΠΈΠΈ ΡΠ΅Π°ΠΊΡΠΈΠΈ Fe2O3 + Al+ Cr= Al2O3+Fe+ Cr Π° ΡΠ°ΠΊΠΆΠ΅ Π΄Π°Π½Π½ΡΠ΅ ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡΡ (2430 Π) ΠΈ Π½Π°ΠΈΠ±ΠΎΠ»ΡΡΠ΅ΠΉ Π²Π½ΡΡΡΠ΅Π½Π½Π΅ΠΉ ΡΠ½Π΅ΡΠ³ΠΈΠ΅ΠΉ S (4076,2 ΠΊΠΠΆ/(ΠΊΠ³*Π)).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?
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)
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
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
- β¦