35 research outputs found
IMPACT OF SOCIAL DISTANCING IN CURBING COVID-19 PANDEMIC: A SYSTEMATIC REVIEW
Social distancing includes strategies to ban public gatherings and advise individuals to stay at their home or maintain distance to one another by at least 1-2 meters. This study aims to intend to assess all the available evidence of social distancing in decreasing COVID-19 transmission in the general population. We conducted an electronic search of published literature using MEDLINE/Pubmed, Science direct, PMC, Wiley, and Google Scholar and we use Joanna Briggs Institute (JBI) critical appraisal checklist to assess methodological qualities. A total of 7 articles were decided to be included in this study. Social distancing has curb down the number and saved approximately 10 thousand Brazilian lives. A study by VoPham et al on the association of social distancing and COVID-19 incidence found higher social distancing was associated with a 29% reduction of COVID-19 incidence (adjusted IRR 0.71;95% CI (0,57-0,87) and 35% reduction of COVID-19 mortality (adjusted IRR 0,65; 95% CI 0,55-0,76). Social distancing is one of the major policies implemented for long-term behavioral adjustment in managing the COVID-19 pandemic. Passive social distancing is not enough to drag down the number, there needs to be large scale testing, isolation, and contact tracing. However, we believe we have illuminated the impact of social distancing on the COVID-19 pandemic and add to the available literature the basis of social distancing in reducing transmission of COVID-19
Surface electrons at plasma walls
In this chapter we introduce a microscopic modelling of the surplus electrons
on the plasma wall which complements the classical description of the plasma
sheath. First we introduce a model for the electron surface layer to study the
quasistationary electron distribution and the potential at an unbiased plasma
wall. Then we calculate sticking coefficients and desorption times for electron
trapping in the image states. Finally we study how surplus electrons affect
light scattering and how charge signatures offer the possibility of a novel
charge measurement for dust grains.Comment: To appear in Complex Plasmas: Scientific Challenges and Technological
Opportunities, Editors: M. Bonitz, K. Becker, J. Lopez and H. Thomse
Anomalous resistivity and the origin of a heavy mass in the two-band Hubbard model with one narrow band
We search for marginal Fermi-liquid behavior in the two-band Hubbard model
with one narrow band. We consider the limit of low electron densities in the
bands and strong intraband and interband Hubbard interactions. We analyze the
influence of electron polaron effect and other mechanisms of mass-enhancement
(related to momentum dependence of the self-energies) on effective mass and
scattering times of light and heavy components in the clean case (electron -
electron scattering and no impurities). We find the tendency towards
phase-separation (towards negative partial compressibility of heavy particles)
in a 3D case for large mismatch between the densities of heavy and light bands
in a strong coupling limit. We also observe that for low temperatures and equal
densities the resistivity in a homogeneous state R(T) ~ T^2 - behaves in a
Fermi-liquid fashion both in 3D and 2D cases. For temperatures higher then
effective bandwidth for heavy electrons T > Wh* the coherent behavior of heavy
component is totally destroyed. The heavy particles move diffusively in the
surrounding of light particles. At the same time the light particles scatter on
the heavy ones as if on immobile (static) impurities. In this regime the heavy
component is marginal, while the light one is not. The resistivity goes on
saturation for T > Wh* in the 3D case. In 2D the resistivity has a maximum and
localization tail due to weak - localization corrections of Altshuler - Aronov
type. Such behavior of resistivity in 3D could be relevant for some
uranium-based heavy-fermion compounds like UNi2Al3 and in 2D for some other
mixed-valence compounds possibly including the layered manganites. We also
consider briefly the superconductive (SC) instability in the model. The leading
instability is towards p-wave pairing and is governed by enhanced Kohn -
Luttinger mechanism of SC at low electron density.Comment: 37 pages, 9 figures, accepted for JET
Risk Factors For The Event Of Pediculosis Capitis In The Baturaja Orphanage, South Sumatera, Indonesia
Introduction. Pediculosis capitis is a disease of the scalp caused by infestation of Pediculus humanus capitis with symptoms such as itching and sensation of movement in the hair. The purpose of this study was to determine the risk factors and incidence of pediculosis capitis in the Baturaja orphanage.Methods. This research is an analytic observational study using a cross-sectional design with field and laboratory research. The population of this study were all children in the Baturaja orphanage who met the inclusion and exclusion criteria, as many as 172 children. All children present were taken as subjects. Data obtained by questionnaires, interviews and direct observation of the sample.Results. The results of this study showed the prevalence of pediculosis capitis in the Baturaja orphanage was 19.1%. In this study, it was found that there was a significant relationship between age (p = 0.000), education (p = 0.000), the use of shared pillows (p = 0.000), the use of shared combs (p = 0.000), the use of shared towels (p = 0.000), knowledge (p = 0.000), attitudes and behavior (p = 0.000) with the incidence of pediculosis capitis. Multivariate analysis showed that the most dominant risk factor for the incidence of pediculosis capitis in the Baturaja orphanage was age (p=0.036), while behavior was a protective factor for the incidence of pediculosis capitis.Conclusion. There is a significant relationship between age, education, use of shared pillows, use of shared combs, use of shared towels, knowledge, attitudes, behavior with the incidence of pediculosis capitis. The most dominant risk factor for the incidence of pediculosis capitis in the Baturaja orphanage is age, while behavior is a protective factor for the incidence of pediculosis capitis
AKT-sensitive or insensitive pathways of toxicity in glial cells and neurons in Drosophila models of Huntington's disease
Heavy water labeling of DNA for measurement of cell proliferation and recruitment during primary murine lymph node responses against model antigens
Expanded polyglutamine peptides disrupt EGF receptor signaling and glutamate transporter expression in Drosophila
Decreasing glutamate buffering capacity triggers oxidative stress and neuropil degeneration in the Drosophila brain
AbstractL-glutamate is both the major brain excitatory neurotransmitter [1, 2] and a potent neurotoxin [3, 4] in mammals. Glutamate excitotoxicity is partly responsible for cerebral traumas evoked by ischemia [5, 6] and has been implicated in several neurodegenerative diseases including amyotrophic lateral sclerosis (ALS) [7–9]. In contrast, very little is known about the function or potential toxicity of glutamate in the insect brain. Here, we show that decreasing glutamate buffering capacity is neurotoxic in Drosophila. We found that the only Drosophila high-affinity glutamate transporter, dEAAT1 [10–13], is selectively addressed to glial extensions that project ubiquitously through the neuropil close to synaptic areas. Inactivation of dEAAT1 by RNA interference led to characteristic behavior deficits that were significantly rescued by expression of the human glutamate transporter hEAAT2 or the administration in food of riluzole, an anti-excitotoxic agent used in the clinic for human ALS patients. Signs of oxidative stress included hypersensitivity to the free radical generator paraquat and rescue by the antioxidant melatonin. Inactivation of dEAAT1 also resulted in shortened lifespan and marked brain neuropil degeneration characterized by widespread microvacuolization and swollen mitochondria. This suggests that the dEAAT1-deficient fly provides a powerful genetic model system for molecular analysis of glutamate-mediated neurodegeneration