An estimate for the thermal photon rate from lattice QCD

We estimate the production rate of photons by the quark-gluon plasma in lattice QCD. We propose a new correlation function which provides better control over the systematic uncertainty in estimating the photon production rate at photon momenta in the range {\pi}T/2 to 2{\pi}T. The relevant Euclidean vector current correlation functions are computed with $N_{\mathrm f}$ = 2 Wilson clover fermions in the chirally-symmetric phase. In order to estimate the photon rate, an ill-posed problem for the vector-channel spectral function must be regularized. We use both a direct model for the spectral function and a model-independent estimate from the Backus-Gilbert method to give an estimate for the photon rate.Comment: 15 pages, 11 figures, talk presented at 35th annual International Symposium on Lattice Field Theory, 18-24 June 2017, Granada, Spai

SDGS in children during the COVID-19 pandemic in Indonesia

This global pandemic negatively affects many aspects of children and adolescent health in Indonesia, including our journey in achieving SDGs. Even before the pandemic, our country is not yet on the right track in our SDGs journey with no national comprehensive programs. If we do not urgently address the problems in our nation’s health system, the COVID-19 pandemic can be detrimental to our SDGs progress

EFFECTS OF STATIC STRETCHING, PNF STRETCHING, AND DYNAMIC WARM-UP ON MAXIMUM POWER OUTPUT AND FATIGUE

The purpose of this study was to determine the effects of static stretching, PNF stretching, and dynamic warm-up on maximum power output and fatigue. Ten participants were recruited to perform a vertical jump test at 3 minutes and 20 minutes post-treatment for all treatments until voluntary fatigue. Participants performed a standard protocol including one of the stretching/warm-up treatments followed by two repeated, counter-movement, vertical jump tests. Results of the study showed no statistically significant differences in maximum power output although the dynamic warm-up group resulted in a 10% and 9% higher average output compared to the control group. Results also showed no statistically significant differences in percent decline in power output as well as time to voluntary fatigue, although there was up to a 6 s difference between treatments and the control group. Although this study concluded with no statistical significance, an argument could be made for applicable significance

Ultralong-Range Rydberg Molecules in a Divalent-Atomic System

We report the creation of ultralong-range Sr$_2$ molecules comprising one ground-state $5s^2$ $^1S_0$ atom and one atom in a $5sns$ $^3S_1$ Rydberg state for $n$ ranging from 29 to 36. Molecules are created in a trapped ultracold atomic gas using two-photon excitation near resonant with the $5s5p$ $^3P_1$ intermediate state, and their formation is detected through ground-state atom loss from the trap. The observed molecular binding energies are fit with the aid of first-order perturbation theory that utilizes a Fermi pseudopotential with effective $s$-wave and $p$-wave scattering lengths to describe the interaction between an excited Rydberg electron and a ground-state Sr atom.Comment: 5 pages, 2 figure

Midbrain dopamine neurons signal phasic and ramping reward prediction error during goal-directed navigation

Goal-directed navigation requires learning to accurately estimate location and select optimal actions in each location. Midbrain dopamine neurons are involved in reward value learning and have been linked to reward location learning. They are therefore ideally placed to provide teaching signals for goal-directed navigation. By imaging dopamine neural activity as mice learned to actively navigate a closed-loop virtual reality corridor to obtain reward, we observe phasic and pre-reward ramping dopamine activity, which are modulated by learning stage and task engagement. A Q-learning model incorporating position inference recapitulates our results, displaying prediction errors resembling phasic and ramping dopamine neural activity. The model predicts that ramping is followed by improved task performance, which we confirm in our experimental data, indicating that the dopamine ramp may have a teaching effect. Our results suggest that midbrain dopamine neurons encode phasic and ramping reward prediction error signals to improve goal-directed navigation

Thermoacoustic Instability Suppression and Heat-Release Forcing of a Laminar Flame Using Ionic Wind

Advancements in combustion technologies are often impeded by complex combustion dynamics. Active control has proven effective at mitigating these dynamics in the lab, but mass adoption requires more affordable, lightweight, and reliable actuators. Here, a new actuator concept is presented which utilizes sub-breakdown electric fields, the inherent plasma nature of flames, and the electrohydrodynamic effect to create flame stabilization points. These electrically controlled stabilization points allow variable distortion of a laminar flame and bidirectional forcing of the flame heat release. The electric field-based actuator is combined with a simple feedback controller to demonstrate suppression of a thermoacoustic instability. The instability sound pressure level was reduced by 27 dB and in less than 60 ms upon enabling the controller. The use of a sub breakdown electric field requires a mere 40 mW to stabilize a 3.4 kW thermal power flame. The absence of any moving parts and low electrical power required make this a promising actuator concept for many combustion applications.Comment: Supplementary Videos here: https://dustincruise.com/flame-videos

Does greater financial openness promote external competitiveness in emerging markets? The role of institutional quality

Studies have shown that external capital account liberalisation can boost capital inflows and augment economic development. Nevertheless, in the case of developing and emerging economies (DEE), adverse currency fluctuations could hamper external competitiveness due to relative price differences creating currency overvaluation, which might not be mitigated via financial openness alone. Therefore, this paper uses annual panel data for 35 DEEs over 40 years to explore whether financial openness of countries can help preserve their external price competitiveness, in the presence of greater trade openness and better institutional quality. Our findings suggest that financial openness alone does not aid export competitiveness, unless it is supported by greater trade openness. In addition, both cross country and regional analyses show that financial openness can benefit economies in maintaining their export competitiveness if they have stronger quality of institutions. Our results remain robust when we estimate the role of financial openness and institutional quality jointly on external competitiveness across regions, and during the pre‐ and post‐crisis periods. We conclude that financial openness alone is not sufficient to improve external competitiveness of an emerging economy, but it does help in the presence of greater trade openness or better institutions, enabling reduction in trade costs and thereby making these countries more price‐competitive