6,676 research outputs found
Child externalising and internalising behaviour and parental wellbeing during the Covid-19 pandemic
In this study we surveyed families' experiences with parental depression, stress, relationship conflict and child behavioural issues during 6 months of the coronavirus (Covid-19) pandemic through the Covid-19: Global Social Trust and Mental Health Study. The current analyses used data collected from online surveys completed by adults in 66 countries from 17 April 2020 to 13 July 2020 (Wave I), followed by surveys 6 months later at Wave II (17 October 2020-31 January 2021). Analyses were limited to 175 adult parents who reported living with at least one child under 18 years old at Wave I. Parents reported on children's level of externalising and internalising behaviour at Wave I. At Wave II, parents completed self-reported measures of stress, depression and inter-partner conflict. Child externalising behaviour at Wave I significantly predicted higher levels of parental stress at Wave II, controlling for covariates. Child internalising behaviour at Wave I did not predict parental stress or depression, controlling for covariates. Neither child externalising nor internalising behaviour predicted parental relationship conflict. The overall findings demonstrate that child behaviour likely influenced parental stress during the Covid-19 pandemic. Findings suggest that mental health interventions for children and parents may improve the family system during times of disaster
Low-error and broadband microwave frequency measurement in a silicon chip
Instantaneous frequency measurement (IFM) of microwave signals is a
fundamental functionality for applications ranging from electronic warfare to
biomedical technology. Photonic techniques, and nonlinear optical interactions
in particular, have the potential to broaden the frequency measurement range
beyond the limits of electronic IFM systems. The key lies in efficiently
harnessing optical mixing in an integrated nonlinear platform, with low losses.
In this work, we exploit the low loss of a 35 cm long, thick silicon waveguide,
to efficiently harness Kerr nonlinearity, and demonstrate the first on-chip
four-wave mixing (FWM) based IFM system. We achieve a large 40 GHz measurement
bandwidth and record-low measurement error. Finally, we discuss the future
prospect of integrating the whole IFM system on a silicon chip to enable the
first reconfigurable, broadband IFM receiver with low-latency.Comment: 13 pages, 7 figure
Child Externalizing and Internalizing Behavior and Parental Well-Being During the COVID-19 Pandemic
In this study we surveyed families’ experiences with parental depression, stress, relationship conflict, and child behavioral issues during six months of the COVID-19 pandemic through the COVID-19: Global Social Trust and Mental Health Study. The current analyses used data collected from online surveys completed by adults in 66 countries from April 17, 2020-July 14, 2020 (Wave I), followed by surveys six months later at Wave II (October 17, 2020-January 31, 2021). Analyses were limited to 175 adult parents who reported living with at least one child under 18 years old at Wave I. Parents reported on children’s level of externalizing and internalizing behavior at Wave I. At Wave II, parents completed self-reported measures of stress, depression, and inter-partner conflict. Child externalizing behavior at Wave I significantly predicted higher levels of parental stress and marginally predicted parental depression at Wave II, controlling for covariates. Child internalizing behavior at Wave I did not predict parental stress or depression, controlling for covariates. Neither child externalizing nor internalizing behavior predicted parental relationship conflict. The overall findings demonstrate that child behavior likely influenced parental stress and depression during the COVID-19 pandemic. Findings suggest that mental health interventions for children and parents may improve the family system during times of disaster
Cornering the unphysical vertex
In the classical pure spinor worldsheet theory of AdS5xS5 there are some
vertex operators which do not correspond to any physical excitations. We study
their flat space limit. We find that the BRST operator of the worldsheet theory
in flat space-time can be nontrivially deformed without deforming the
worldsheet action. Some of these deformations describe the linear dilaton
background. But the deformation corresponding to the nonphysical vertex differs
from the linear dilaton in not being worldsheet parity even. The nonphysically
deformed worldsheet theory has nonzero beta-function at one loop. This means
that the classical Type IIB SUGRA backgrounds are not completely characterized
by requiring the BRST symmetry of the classical worldsheet theory; it is also
necessary to require the vanishing of the one-loop beta-function.Comment: LaTeX 40pp; v2: explained the relation to the linear dilaton
background (Section 6), changes in Introduction and Abstrac
All-integrated universal RF photonic spectral shaper
We demonstrate a microwave photonic spectral shaper in a silicon chip enabling distinct phase and amplitude modulation transformation. We show unprecedented RF filtering through monolithic integration of the spectral shaper with tunable ring resonators
Phase diagram of silicon from atomistic simulations
In this letter we present a calculation of the temperature-pressure phase
diagram of Si in a range of pressures covering from -5 to 20 GPa and
temperatures up to the melting point. The phase boundaries and triple points
between the diamond, liquid, -Sn and clathrate phases are
reported. We have employed efficient simulation techniques to calculate free
energies and to numerically integrate the Clausius-Clapeyron equation, combined
with a tight binding model capable of an accuracy comparable to that of
first-principles methods. The resulting phase diagram agrees well with the
available experimental data.Comment: 5 pages, 1 figure, accepted in PR
FĂ©vre, FermĂn. La postmodernidad en el arte. Bs. As. Editorial Lexicus.
Fil: Bedoya, J. Universidad de Buenos Aires, Facultad de FilosofĂa y Letras, Instituto de Historia de las Artes "Julio E. PayrĂł"; Argentina
Methylation-Dependent Gene Silencing Induced by Interleukin 1β via Nitric Oxide Production
Interleukin (IL)-1β is a pleiotropic cytokine implicated in a variety of activities, including damage of insulin-producing cells, brain injury, or neuromodulatory responses. Many of these effects are mediated by nitric oxide (NO) produced by the induction of NO synthase (iNOS) expression. We report here that IL-1β provokes a marked repression of genes, such as fragile X mental retardation 1 (FMR1) and hypoxanthine phosphoribosyltransferase (HPRT), having a CpG island in their promoter region. This effect can be fully prevented by iNOS inhibitors and is dependent on DNA methylation. NO donors also cause FMR1 and HPRT gene silencing. NO-induced methylation of FMR1 CpG island can be reverted by demethylating agents which, in turn, produce the recovery of gene expression. The effects of IL-1β and NO appear to be exerted through activation of DNA methyltransferase (DNA MeTase). Although exposure of the cells to NO does not increase DNA MeTase gene expression, the activity of the enzyme selectively increases when NO is applied directly on a nuclear protein extract. These findings reveal a previously unknown effect of IL-1β and NO on gene expression, and demonstrate a novel pathway for gene silencing based on activation of DNA MeTase by NO and acute modification of CpG island methylation
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