RESUMO
The COVID-19 pandemic in the United States has had a disproportionate impact on Black, low-income, and elderly individuals. We recruited 175 predominantly white children ages 5-12 and their parents (N = 112) and asked which of two individuals (differing in age, gender, race, social class, or personality) was more likely to get sick with either COVID-19 or the common cold and why. Children and parents reported that older adults were more likely to get sick than younger adults, but reported few differences based on gender, race, social class, or personality. Children predominantly used behavioral explanations, but older children used more biological and structural explanations. Thus, children have some understanding of health disparities, and their understanding increases with age.
RESUMO
Do children think of genetic inheritance as deterministic or probabilistic? In two novel tasks, children viewed the eye colors of animal parents and judged and selected possible phenotypes of offspring. Across three studies (N = 353, 162 girls, 172 boys, 2 non-binary; 17 did not report gender) with predominantly White U.S. participants collected in 2019-2021, 4- to 12-year-old children showed a probabilistic understanding of genetic inheritance, and they accepted and expected variability in the genetic inheritance of eye color. Children did not show a mother bias but they did show two novel biases: perceptual similarity and sex-matching. These results held for unfamiliar animals and several physical traits (e.g., eye color, ear size, and fin type), and persisted after a lesson.
Assuntos
Mães , Pais , Criança , Masculino , Feminino , Animais , Humanos , Pré-EscolarRESUMO
Question-asking is a crucial tool for acquiring information about unseen entities, such as viruses; thus, examining children's questions within the context of COVID-19 is particularly important for understanding children's learning about the coronavirus. The study examined 3-12-year-old children's questions and teachers' responses about the COVID-19 pandemic in Türkiye, a non-Western developing context, and the United States, a Western cultural context. A total of 119 teachers from Türkiye and 95 teachers from the US participated in the study. Teachers completed an online survey consisting of a demographic form and a questionnaire asking them to report three questions about COVID-19 asked by children in their classrooms and their responses to these questions. We analyzed children's questions and teachers' responses for their type and content and examined demographic factors associated with children's questions and teachers' responses. Consistent with the literature, children from Türkiye asked fewer explanation-seeking (i.e., why/how) questions than children from the United States. Children asked questions about viruses and precautions. Teachers responded to children's questions realistically in both countries. The findings have important implications for how children gain knowledge from teachers when discussing health, disease, and virus topics in two countries.
Assuntos
COVID-19 , Professores Escolares , Humanos , COVID-19/epidemiologia , COVID-19/psicologia , Criança , Professores Escolares/psicologia , Estados Unidos/epidemiologia , Feminino , Masculino , Inquéritos e Questionários , Pré-Escolar , Adulto , SARS-CoV-2/isolamento & purificação , PandemiasRESUMO
Phytochromes are red-light photoreceptors discovered in plants with homologs in bacteria and fungi that regulate a variety of physiological responses. They display a reversible photocycle between two distinct states: a red-light-absorbing Pr state and a far-red light-absorbing Pfr state. The photoconversion regulates the activity of an enzymatic domain, usually a histidine kinase (HK). The molecular mechanism that explains how light controls the HK activity is not understood because structures of unmodified bacterial phytochromes with HK activity are missing. Here, we report three cryo-electron microscopy structures of a wild-type bacterial phytochrome with HK activity determined as Pr and Pfr homodimers and as a Pr/Pfr heterodimer with individual subunits in distinct states. We propose that the Pr/Pfr heterodimer is a physiologically relevant signal transduction intermediate. Our results offer insight into the molecular mechanism that controls the enzymatic activity of the HK as part of a bacterial two-component system that perceives and transduces light signals.
Assuntos
Microscopia Crioeletrônica , Fitocromo , Transdução de Sinais , Fitocromo/metabolismo , Fitocromo/química , Microscopia Crioeletrônica/métodos , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Histidina Quinase/metabolismo , Histidina Quinase/química , Modelos Moleculares , Multimerização Proteica , Luz , Fotorreceptores Microbianos/metabolismo , Fotorreceptores Microbianos/químicaRESUMO
La realización de una sesión de hemodiálisis (HD) supone un cierto riesgo de aparición de reacciones adversas de hipersensibilidad, al estar en contacto abundantes cantidades de sangre con diferentes materiales de origen sintético. En HD han sido descritas reacciones de hipersensibilidad al óxido de etileno y a membranas no biocompatibles como el cuproamonio. También se han comunicado casos de hipersensibilidad con membranas biocompatibles como la polisulfona, e incluso con polisulfona asociada a polivinilpirrolidona. En este artículo queremos describir seis casos acontecidos en nuestro servicio de reacciones de hipersensibilidad mayoritariamente temprana a la sesión de HD, caracterizados por mal estado general, desaturación, broncoespasmo e hipotensión arterial, con buena respuesta a la suspensión temporal de la sesión y con reaparición en sesiones posteriores siempre que se utilizase un dializador sintético. Todas tienen en común no haberse dado de nuevo en sucesivas observaciones cuando las sesiones fueron realizadas con una membrana de celulosa (AU)
Undergoing a haemodialysis (HD) session poses a certain risk of hypersensitivity adverse reactions as large quantities of blood are in contact with various synthetic materials. Hypersensitivity reactions to ethylene oxide and non-biocompatible membranes, such as cuprophane, have been described in HD. Cases of hypersensitivity with biocompatible membranes, such as polysulfone, and even polysulfone-polyvinylpyrrolidone, have also been reported. In this article we describe six cases of mostly early-stage hypersensitivity reactions to HD occurring in our department, characterised by malaise, desaturation, bronchospasm and arterial hypotension, with good response to the session's temporary suspension and with reappearance in subsequent sessions that used a synthetic dialyser. No hypersensitivity reactions reappeared in successive observations when the sessions were carried out using a cellulose membrane (AU)