Finally, we provided policy proposals that support our findings.In this paper, we consider a delayed diffusive SVEIR model with general incidence. We first establish the threshold dynamics of this model. Using a Nonstandard Finite Difference (NSFD) scheme, we then give the discretization of the continuous model. Applying Lyapunov functions, global stability of the equilibria are established. Numerical simulations are presented to validate the obtained results. The prolonged time delay can lead to the elimination of the infectiousness.

Supplementary material is available in the online version of this article at 10.1007/s10473-021-0421-9.

Supplementary material is available in the online version of this article at 10.1007/s10473-021-0421-9.Here we report a new procedure to determine Pu-239 in urine using a custom-made automated pre-analytical processing system (single probe) with Pu-242 as a tracer followed by analysis by SF-ICP-MS. An average Pu-242 recovery rate of 88% was obtained with CF-ThU-1000 columns reused >100 times. Analytical results agree with measurements obtained using the CDC manual method with a R2 of 0.9994. Results for Oak Ridge National Laboratory (ORNL) reference materials (RM) align with target values with a bias range of -3.44% to 3.05%. The limit of detection for this method is 0.63 pg/L, which is comparable to previous manual methods.

The lockdown periods associated with the Covid-19 pandemic are a particularly significant challenge for families of children with autism. Exchanges by e-mail and interviews were aimed at collecting testimonies from parents for a better understanding of their difficulties and the help provided by the mobilization of professionals.

Eight parents of autistic children living in the Seine-Saint-Denis area agreed to testify about their experience, either in person, taking into account the barrier measures after the first lockdown, or by telephone during the second lockdown. By way of comparison, e-mails were exchanged with a mother and two fathers of autistic children from higher socio-economic backgrounds living in other parts of France or Belgium. While at the beginning of the first lockdown, some children may have felt soothed by being at home with their parents, the extension of the situation led to crises related to feelings of anxiety or boredom. Despite the closure of many medical-social facilities, prof group workshops were organized, and consultations were given at a distance. The teams of the child psychiatry services and the medico-social services have mobilized themselves and have shown reactivity and inventiveness in order to ensure the care and follow-up of children and their families.This paper shows that, in a two-country model, where the two economies differ in their level of financial market development, financial integration has sizable short- and medium-term effects, even in the absence of aggregate risks. Consistent with the Lucas paradox, the present work establishes that financial integration can reduce the speed of capital accumulation and increase savings in a developing country still in the process of convergence toward the steady state and with domestic capital market distortions. The level of capital accumulation at the time of integration crucially affects agents’ welfare. The closer the economy is to its steady state, the lower are agents’ welfare gains in the financially less advanced economy, while they are always negative in the more developed country. Two forces drive these results precautionary saving and the propensity to move resources from risky capital to safe assets until the risk-adjusted return on capital equalizes the risk-free interest rate. Under the assumption of the constant relative-risk-aversion utility function, those forces are both decreasing in wealth.Two studies examine psychological and demographic factors that predict attitudes toward mask-wearing during the COVID-19 pandemic. These studies differentiate pro-mask from anti-mask attitudes. Political conservatism, younger age, and gender predicted anti-mask attitudes but were unrelated to pro-mask attitudes. Temsirolimus Psychological reactance was associated with anti-mask attitudes, over and above demographic variables. Empathy, trust in healthcare professionals, and perceived normativity of mask wearing were associated with pro-mask attitudes, over and above demographic variables. These studies suggest that demographic variables such as political orientation and age are associated with anti-mask but not pro-mask attitudes, but also that psychological factors differentially predict anti- and pro-mask attitudes over and above demographic factors.Slime mold algorithm (SMA) is a recently developed meta-heuristic algorithm that mimics the ability of a single-cell organism (slime mold) for finding the shortest paths between food centers to search or explore a better solution. It is noticed that entrapment in local minima is the most common problem of these meta-heuristic algorithms. Thus, to further enhance the exploitation phase of SMA, this paper introduces a novel chaotic algorithm in which sinusoidal chaotic function has been combined with the basic SMA. The resultant chaotic slime mold algorithm (CSMA) is applied to 23 extensively used standard test functions and 10 multidisciplinary design problems. To check the validity of the proposed algorithm, results of CSMA has been compared with other recently developed and well-known classical optimizers such as PSO, DE, SSA, MVO, GWO, DE, MFO, SCA, CS, TSA, PSO-DE, GA, HS, Ray and Sain, MBA, ACO, and MMA. Statistical results suggest that chaotic strategy facilitates SMA to provide better performance in terms of solution accuracy. The simulation result shows that the developed chaotic algorithm outperforms on almost all benchmark functions and multidisciplinary engineering design problems with superior convergence.In the United States, the SNAP and TANF programs provide financial support to low-income households with children. Yet, little is known about the extent of this support over the early childhood period or how program participation varies by race (or ethnicity) and metropolitan county residence. We use administrative data from Virginia to document participation in SNAP and TANF among children born between 2007 and 2010 during their early childhood period, which we define here as birth to age six. We find that participation in SNAP is about four times greater than participation in TANF and that most children begin their connection with the social welfare system in their birth year. Children who participate earlier in life tend to stay connected over a longer portion of the early childhood period, although SNAP participation peaks around ages 3-4 while TANF peaks earlier, around ages 2-3. Most households on SNAP do not receive TANF, but only about 1 in 12 children on TANF do not receive SNAP. Finally, over the early childhood period, on average, just under 1 in 2 children in Virginia participated in SNAP or TANF but demography plays an important role in this process The level of cumulative receipt is 1 in 4 among White children, 1 in 2 among Hispanic children but rises to 3 in 4 for Black children; cumulative receipt is also higher in nonmetropolitan counties than metropolitan counties.