Central bank digital currency and cryptocurrency in emerging markets

Blockchain technology has opened up the possibility of digital currency, smart contracts and much more applications including the launch of central bank digital currencies (CBDC). However, literature about the effect of CBDC with the presence of cryptocurrency for an emerging market economy seems to be left behind. In this paper, we introduce a New Keynesian - Dynamic Stochastic General Equilibrium (NK-DSGE) model to examine the implications of CBDC and cryptocurrency in an open economy for emerging markets. In our model, cryptocurrency is implemented as a form of deposit in banks where bankers can also receive deposits from abroad. Lastly, CBDC is introduced as a payment and saving instrument. We find that cryptocurrency has a crucial role in banking sectors and a significant effect on the dynamic of foreign debt which is deeply important for emerging markets. We also conduct optimal monetary policy under different scenarios. Hence, we uncover that a flexible rate in CBDC can affect the responses of the monetary rate and can reinforce the conventional monetary policy to achieve the central bank's targets

Probabilistic picture for particle number densities in stretched tips of the branching Brownian motion

In the framework of a stochastic picture for the one-dimensional branching Brownian motion, we compute the probability density of the number of particles near the rightmost one at a time $T$, that we take very large, when this extreme particle is conditioned to arrive at a predefined position $x_T$ chosen far ahead of its expected position $m_T$. We recover the previously-conjectured fact that the typical number density of particles a distance $\Delta$ to the left of the lead particle, when both $\Delta$ and $x_T-\Delta-m_T$ are large, is smaller than the mean number density by a factor proportional to $e^{-\zeta\Delta^{2/3}}$, where $\zeta$ is a constant that was so far undetermined. Our picture leads to an expression for the probability density of the particle number, from which a value for $\zeta$ may be inferred.Comment: 6 pages, 1 figur

The Relation Between Peer Victimization and Changes in Trauma Symptoms in Adolescents

Peer victimization has been shown to negatively impact youth functioning and may be especially damaging during adolescence, given the increased importance of peers. However, there is a dearth of longitudinal research examining trauma symptomatology as an outcome of peer victimization with low-income, ethnic minority adolescents. The present study investigated this relation in a predominantly African American sample of 684 students assessed at five time points between the fall of their sixth grade and seventh grade school years. Growth mixture models grouped participants with similar victimization trajectories, and latent growth models related growth trajectories of physical and relational victimization to changes in trauma symptoms. Although initial levels of victimization were unrelated to changes in trauma symptoms over time, increasing victimization was associated with increasing trauma symptoms. These findings provide insight into the relation between peer victimization and trauma in an underserved sample of adolescents, with important implications for prevention efforts

Cyberbullying among adolescents: Measures in search of a construct

Objective: This review focuses on the literature on cyberbullying among adolescents. Currently, there is no unified theoretical framework to move the field of cyberbullying forward. Due to some unique features of cyberbullying, researchers have generally assumed that it is distinct from aggression perpetrated in person. Many measures of cyberbullying have been developed based on this assumption rather than to test competing models and inform a theoretical framework for cyberbullying. Approach: We review current theory and research on cyberbullying within the context of the broader literature on aggression to explore the usefulness of the assumption that cyberbullying represents a distinct form of aggression. Associations between cyberbullying and general forms of aggression and psychosocial predictors of cyberbullying are discussed. Conclusions: Based on the empirical research, we suggest that the media through which aggression is perpetrated may be best conceptualized as a new dimension on which aggression can be classified, rather than cyberbullying as a distinct counterpart to existing forms of aggression. Research on cyberbullying should be considered within the context of theoretical and empirical knowledge of aggression in adolescence. Using this approach will create a theoretical framework for understanding cyberbullying, focus future research, and guide prevention efforts

Relativistic dynamical polarizability of hydrogen-like atoms

Using the operator representation of the Dirac Coulomb Green function the analytical method in perturbation theory is employed in obtaining solutions of the Dirac equation for a hydrogen-like atom in a time-dependent electric field. The relativistic dynamical polarizability of hydrogen-like atoms is calculated and analysed.Comment: 15 pages, 3 figures (not included, but hard copies are available upon request

Relations of diet and physical activity to bone mass and height in black and white adolescents

Because the development of healthy bodies during the years of growth has life-long health consequences, it is important to understand the early influences of diet and physical activity (PA). One way to generate hypotheses concerning such influences is to conduct cross-sectional studies of how diet and PA are related to different components of body composition. The subjects were 660 black and white adolescents. Total body bone mineral content (BMC) was measured with dual-energy X-ray absorptiometry; free-living diet and PA were assessed with 4–7 separate 24-h recalls. The main dietary variables investigated were: total energy intake, macronutrient distribution (%), dairy servings, vitamin D, and calcium. The main PA variables were hours of moderate PA (3–6 METs) and vigorous PA (>6 METs). BMC was higher in blacks than in whites (P<0.01) and it increased more in boys than in girls (age by sex interaction) as age increased (P<0.01). After adjustment for age, race and sex, higher levels of BMC were associated with higher levels of energy intake, dairy servings, calcium, vitamin D, and vigorous PA (all P 's<0.05). In the multivariable model, significant and independent proportions of the variance in BMC were explained by race, the age by sex interaction, calcium, and vigorous PA (all P 's<0.01). When height was used as the outcome variable, similar diet results were obtained; however, there was a sex by vigorous PA interaction, such that vigorous PA was associated with height only in the girls. These data are consistent with the hypothesis that the bone mass and height of growing youths are positively influenced by higher dietary intake of energy and dairy foods, along with sufficient amounts of vigorous PA. This hypothesis needs to be tested in randomized controlled trials

Benchmarking accurate spectral phase retrieval of single attosecond pulses

Citation: Wei, H., Le, A. T., Morishita, T., Yu, C., & Lin, C. D. (2015). Benchmarking accurate spectral phase retrieval of single attosecond pulses. Physical Review A, 91(2), 15. doi:10.1103/PhysRevA.91.023407A single extreme-ultraviolet (XUV) attosecond pulse or pulse train in the time domain is fully characterized if its spectral amplitude and phase are both determined. The spectral amplitude can be easily obtained from photoionization of simple atoms where accurate photoionization cross sections have been measured from, e.g., synchrotron radiations. To determine the spectral phase, at present the standard method is to carry out XUV photoionization in the presence of a dressing infrared (IR) laser. In this work, we examine the accuracy of current phase retrieval methods (PROOF and iPROOF) where the dressing IR is relatively weak such that photoelectron spectra can be accurately calculated by second-order perturbation theory. We suggest a modified method named swPROOF (scattering wave phase retrieval by omega oscillation filtering) which utilizes accurate one-photon and two-photon dipole transition matrix elements and removes the approximations made in PROOF and iPROOF. We show that the swPROOF method can in general retrieve accurate spectral phase compared to other simpler models that have been suggested. We benchmark the accuracy of these phase retrieval methods through simulating the spectrogram by solving the time-dependent Schrodinger equation numerically using several known single attosecond pulses with a fixed spectral amplitude but different spectral phases