Seroprevalence of anti-SARS-CoV-2 antibodies among children and their parents in Greece.

School closures were enforced as measures to restrain the COVID-19 pandemic, based on the assumption that young children may play a key role in SARS-CoV-2 spread. This study aims to determine the prevalence of SARS-CoV-2 IgG antibodies in children and corresponding parents, in order to improve surveillance and estimate the prevalence of asymptomatic or subclinical COVID-19 cases. A prospective multicenter study was conducted between March and June 2021 in Greece. Children admitted to the hospital or examined in outpatient clinics for reasons other than COVID-19 and their parents were tested for anti-Spike SARS-CoV-2 IgG in serum. A questionnaire about clinical and demographic data was completed. The study included 823 participants: 427 children and 396 corresponding parents. The overall seroprevalence was 16.4% in parents and 13.8% in children. Among families with ≥ 1 seropositive child or parent, the combination of a seropositive parent and a corresponding seronegative child was 29.6%, a seronegative parent and a corresponding seropositive child was 24.7%, and a seropositive child with a corresponding seropositive parent was 45.7%. Age, level of education, and school or work attendance were not significantly associated with increased seropositivity. On the contrary, ethnic minority of Roma, close contact with known COVID-19 case, previous symptoms consistent with COVID-19, and mass gatherings were risk factors for seropositivity. CONCLUSION: The spread of SARS-CoV-2 during a period of lockdown in Greece was low in children and comparable to adults most likely due to intrafamilial transmission. Accordingly, it is unlikely that children have boosted virus transmission. WHAT IS KNOWN: • In the earliest months of the pandemic, it was demonstrated that children had significantly lower seroprevalence rates than the older age groups, due to the fact that children had decreased exposure to the virus, because of early public health interventions, such as school and day care closure. • Later, further studies reported that children have similar incidence rate of SARS-CoV-2 infection compared to adults in households and community settings. WHAT IS NEW: • In this seroprevalence study, the spread of SARS-CoV-2 infection during a period of lockdown in Greece with the predominance of the Alpha-variant was particularly low in children and comparable to adults, most likely due to intrafamilial transmission. • These study findings will be useful for decisions regarding non-pharmaceutical interventions during the pandemic, and especially, to guide in designing and implementing appropriate containment measures for schools and social gatherings.

The trends for the "trend toward significance" in the pediatric literature.

Purpose This study is to examine whether the term "trend toward statistical significance" is used to describe statistically nonsignificant results in biomedical literature. We examined articles published in five high-impact pediatric journals, including The Lancet Child & Adolescent Health, The Journal of Pediatrics, Early Human Development, Frontiers in Pediatrics, and BMC Pediatrics to identify manuscripts where a "trend" was used to describe a statistically nonsignificant result, from January 2020 to December 2021, and, furthermore, for The Journal of Pediatrics, Early Human Development, and BMC Pediatrics from January 2010 to December 2011. We detected that a "trend toward significance" was used to describe a statistically nonsignificant result at least once in 146 articles (2.7%) during the period between 2020 and 2021 and in 97 articles (4.0%) during the period between 2010 and 2011. We found no significant difference in the proportion of published articles with inappropriate use of "trend" across journals belonging to the first quartile of impact compared to the second quartile or across journals publishing under the subscription model or open access policy compared to journals publishing solely under the open access policy, in any period. The overall proportion of the inappropriate use of "trend" declined significantly between 2010 and 2011 to 2020 and 2021 (p = 0.002, RR 0.66 95% CI 0.51-0.86). CONCLUSION: "Trend" statements were sporadically used to describe statistically nonsignificant results across pediatric literature. The inappropriate use of "trend" to describe almost significant differences could be misleading, and "trend" should be reserved only when a specific statistical test for trend has been performed, or in relation to appropriate scientific definitions. WHAT IS KNOWN: •Previously, researchers have reported inappropriate use of "trend" in articles across anaesthesia or major oncology journals. •In many cases, hypothesized results that are close but not lower than the statistical significance threshold are emphasized as "almost" significant. WHAT IS NEW: •"Trend" statements were sporadically used to describe statistically nonsignificant results across pediatric literature. •Inappropriate use of  "trend" was similar in journals with a subscription model compared to those having an open access policy and decreased within a 10-year period.

Study of the Functionalities of a Biochar Electrode Combined with a Photoelectrochemical Cell.

Biochar has been obtained by pyrolysis of spent malt rootlets under limited oxygen supply and further activated by mixing with KOH and pyrolyzed again at high temperature. The total specific surface area of such activated biochar was 1148 m2 g-1, while that of micropores was 690 m2 g-1. This biochar was used to make a functional electrode by deposition on carbon cloth and was combined with a photoelectrochemical cell. The biochar electrode functioned as a supercapacitor in combination with the electrolyte of the cell, reaching a specific capacity of 98 Fg-1, and it was capable of storing charges generated by the cell, proving current flow both under illumination and in the dark. The same electrode could be used as an air-cathode providing oxygen reduction functionality and thus demonstrating interesting electrocatalyst properties.