RESUMO
Background: Since December 2019, an outbreak of severe respiratory infection (COVID-19) emerged in the city of Wuhan in China. The knowledge, awareness and practice of medical students toward COVID-19 pandemic is of most importance as it demonstrates their preparedness to deal with this pandemic. The objective of this study is to assess the knowledge, awareness and practice of medical students in Sudan universities about COVID 19. Methodogy: This is a cross-sectional study conducted on 19 universities that have medical schools in Sudan. Data from at least 100 medical students from each university were included in the study. Data were collected using an online questionnaire in April 2020. Statistical analysis was conducted using the Statistical Package for Social Science software, version 25. Results: About 2603 medical students from 19 universities were included. Overall good knowledge and practice were demonstrated by the medical students (88.9%) and (78.6%), respectively. Respondents who answered that the most common clinical symptoms of COVID-19 were the main combination of dry cough, fatigue and fever were (27.7%), and the first initial symptom was headache were (48.3%.). (60.2%) Wear medical masks, (95%) said that avoiding crowded places protects against the spread of COVID-19, and (50.7%) have confidence that Sudan can win the battle against the COVID-19. Finally, (68.8%) agreed that COVID-19 will finally be successfully controlled. Conclusion: This study has found that medical students in Sudan demonstrated good knowledge and good practice toward Covid19.
RESUMO
The dynamical properties of multiterminal Josephson junctions (MT-JJs) have attracted interest, driven by the promise of new insights into synthetic topological phases of matter and Floquet states. This effort has culminated in the discovery of Cooper multiplets in which the splitting of a Cooper pair is enabled via a series of Andreev reflections that entangle four (or more) electrons. Here, we show that multiplet resonances can also emerge as a consequence of the three-terminal circuit model. The supercurrent appears due to correlated phase dynamics at values that correspond to the multiplet condition nV1 = -mV2 of applied bias. Multiplet resonances are seen in nanofabricated three-terminal graphene JJs, analog three-terminal JJ circuits, and circuit simulations. The stabilization of the supercurrent is purely dynamical, and a close analog to Kapitza's inverted pendulum problem. We describe parameter considerations that optimize the detection of the multiplet lines both for design of future devices.
Assuntos
Elétrons , VibraçãoRESUMO
When a Josephson junction is exposed to microwave radiation, it undergoes the inverse AC Josephson effectâthe phase of the junction locks to the drive frequency. As a result, the I-V curves of the junction acquire "Shapiro steps" of quantized voltage. If the junction has three or more superconducting contacts, coupling between different pairs of terminals must be taken into account and the state of the junction evolves in a phase space of higher dimensionality. Here, we study the multiterminal inverse AC Josephson effect in a graphene sample with three superconducting terminals. We observe robust fractional Shapiro steps and correlated switching events, which can only be explained by considering the device as a completely connected Josephson network. We successfully simulate the observed behaviors using a modified two-dimensional RCSJ model. Our results suggest that multiterminal Josephson junctions are a playground to study highly connected nonlinear networks with novel topologies.