IR-improved Soft-wall AdS/QCD Model for Baryons

We construct an infrared-improved soft-wall AdS/QCD model for baryons by considering the infrared-modified 5D conformal mass and Yukawa coupling of the bulk baryon field. The model is also built by taking into account the parity-doublet pattern for the excited baryons. When taking the bulk vacuum structure of the meson field to be the one obtained consistently in the infrared-improved soft-wall AdS/QCD model for mesons, we arrive at a consistent prediction for the baryon mass spectrum in even and odd parity. The prediction shows a remarkable agreement with the experimental data. We also perform a calculation for the $\rho(a_1)$ meson-nucleon coupling constant and obtain a consistent result in comparison with the experimental data and many other models.Comment: 12 pages, 4 tables, 1 figure, to be published in PL

Role Of Covid-19 Attributions In Inciting Violence Toward Older Asian Individuals

Older adults in the Asian Americans and Pacific Islanders (AAPI) community faced heightened levels of violence and discrimination during the COVID-19 pandemic. Yet, little is known about the factors driving Asian-specific violence. This study investigated if individuals who attributed COVID-19 to stable factors and anything related to China were more likely to commit violence against older Asian adults. From April 23 to May 5 2020, a survey was conducted with 1498 American individuals (M = 55.19 years, SD = 17.97 years) using two online platforms. Participants who made stable attributions about the origin of COVID-19 were significantly more likely to show a proclivity to commit violent behaviors against older Asian adults. For every unit increase in the degree of stability of COVID-19 attributions made, the odds of committing Asian-specific violence increased by 84.2%. Compared to participants who did not make COVID-19 attributions related to China, those who attributed COVID-19 to anything related to China had 1.91 times the odds of reporting they would commit Asian-specific violence. There is a pertinent need to stem violence against the AAPI community by exercising nuance in COVID-19 related messaging. Future research directions on anti-Asian violence are discussed

Rapid Switching and Modulation by use of Coupled VCSELs

Devices incorporating coupled vertical-cavity surface-emitting lasers (VCSELs) have been proposed as means to effect unprecedentedly rapid modulation and/or switching of light beams in advanced optical communication and information-processing systems. A basic device according to the proposal would comprise two or more VCSELs (1) positioned so close to each other that they are coupled and (2) connected to a current source that biases them at a steady current above the threshold current for lasing. The operation of VCSELs under the conditions stated above has been simulated computationally with an algorithm that solves an approximation of the Maxwell-Bloch equations. (These are nonlinear coupled partial differential equations that model the relevant aspects of the physics of semiconductor lasers.) The results of the simulations show that the intensities of the beams oscillate, out of phase relative to each other, at a frequency that is typically of the order of tens of gigahertz. In particular, one simulation was performed for two coupled VCSELs, each having a circular aperture 5.6 microns in diameter, operating at a wavelength of 980 nm. The results of the simulation showed that the intensities of the two beams oscillated in opposite phase (see Figure 1) at a frequency of 42 GHz. In the far field, the beams were found to be separated by an angle of approx.=8deg. The intensities of the beams were also found to oscillate in the near field, 90deg out of phase with the oscillation in the far field. Figure 2 depicts a simple near-field switching device in which an assembly of microlenses would couple the two oscillating beams to two receivers