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BACKGROUND: The purpose of this systematic review is to summarize what is known about health-related physical fitness (cardiovascular endurance, muscular strength and endurance, flexibility, and body composition) and physical activity among homeschool youth. Findings from this study have implications for all American youth as they return to public school from mandated schooling at home during the COVID-19 pandemic. METHODS: Database engines identified over 22,000 articles with 82 abstracts screened for further review. Of these, 18 full-text articles were additionally screened with 10 cross-sectional articles included in the final review. Articles were condensed into a standard review template and findings were summarized by topic. RESULTS: Cardiovascular endurance findings were inconsistent. Abdominal, but not upper body, muscular strength and endurance were significantly lower in homeschool students. There were no reports on flexibility. Body composition was generally healthy in homeschool students and no differences in physical activity were seen. CONCLUSIONS: Research on health-related physical fitness in homeschool youth is limited and descriptive. Further testing and potential remediation may be needed for cardiovascular endurance, muscular strength and endurance, and flexibility in homeschool youth and their public school counterparts as they return to campus. However, existing literature supports healthy body composition and physical activity in this population.
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COVID-19 , Pandemias , Adolescente , Estudos Transversais , Humanos , Resistência Física , Aptidão Física , SARS-CoV-2 , Instituições AcadêmicasRESUMO
BACKGROUND: Intergenerational friendship has proved useful for older people in increasing socialisation. We explored the feasibility of school students Skyping older people in care homes with the long-term aim of reducing loneliness. METHODS: Six school students from one secondary school and twenty older people, including seven with mild to moderate dementia, from three care homes, engaged in Skype video-calls over six weeks. A conversational aid aimed to help school students maintain conversations was employed. Students and care staff completed feedback forms after each session on video-call usage, usefulness of the conversational aid, and barriers and benefits of video-calls. Six care staff provided further feedback on residents' experiences through unstructured interviews. Interviews and field notes were thematically analysed. RESULTS: Residents enjoyed Skype-calls with school students. Over six weeks, video-calls became longer, and more residents participated. Analysis revealed four themes. First, the intervention led to increased mobility for three older people and improved self-care in regard to personal appearance for five residents. Second, school students and older people formed friendships which inspired the need to meet in person. Third, the use of video-calls enabled participants to view each other's environments in real time. Last, directly experiencing the intervention was important for the continued participation of the care staff in the study. Skype-calls between schools and care homes are feasible and may help reduce loneliness. CONCLUSIONS: Institutional collaboration between educational settings and care homes through cost effective video-calls can be useful to increase socialisation for older people, and promote later on-going use with other external organisations to help reduce loneliness and social isolation.
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BACKGROUND: Video-calls have proven to be useful for older care home residents in improving socialization and reducing loneliness. Nonetheless, to facilitate the acceptability and usability of a new technological intervention, especially among people with dementia, there is a need for user-led design improvements. The current study conducted focus groups with an embedded activity with older people to allow for a person-centered design of a video-call intervention. METHODS: Twenty-eight residents across four care homes in the South West of England participated in focus groups to aesthetically personalize and 'dress-up' the equipment used in a video-call intervention. Each care home was provided with a 'Skype on Wheels' (SoW) device, a wheelable 'chassis' comprising an iPad or tablet for access to Skype, and a telephone handset. During the focus group, residents were encouraged to participate in an activity using colorful materials to 'dress-up' SoW. Comments before, during and after the 'dress up' activity were audio recorded. Framework analysis was used to analyze the focus group data. RESULTS: Older people, including seven with dementia were able to interact with and implement design changes to SoW through aesthetic personalization. Themes arising from the data included estrangement, anthropomorphism, reminiscence, personalization, need for socialization versus fear of socialization and attitudes toward technology. After this brief exposure to SoW, residents expressed the likelihood of using video-calls for socialization in the future. CONCLUSION: Care home residents enjoy engaging with new technologies when given the opportunity to interact with it, to personalize it and to understand its purpose. Low cost aesthetic personalization of technologies can improve their acceptability, usability, and implementation within complex care environments.
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Composite materials consisting of metal and metal oxide phases are being researched intensively for various energy conversion applications where they are often expected to operate under redox conditions at elevated temperature. Understanding of the dynamics of composite evolution during redox cycling is still very limited, yet critical to maximising performance and increasing durability. Here we track the microstructural evolution of a single composite particle over 200 redox cycles for hydrogen production by chemical looping, using multi-length scale X-ray computed tomography. We show that redox cycling triggers a centrifugal redispersion of the metal phase and a centripetal clustering of porosity, both seemingly driven by the asymmetric nature of oxygen exchange in composites. Initially, the particle develops a large amount of internal porosity which boosts activity, but on the long term this facilitates structural and compositional reorganisation and eventually degradation. These results provide valuable insight into redox-driven microstructural changes and also for the design of new composite materials with enhanced durability.
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Membranes are a critical technology for energy-efficient separation processes. The routine method of evaluating membrane performance is a permeation measurement. However, such measurements can be limited in terms of their utility: membrane microstructure is often poorly characterized; membranes or sealants leak; and conditions in the gas phase are poorly controlled and frequently far-removed from the conditions employed in the majority of real processes. Here, we demonstrate a new integrated approach to determine permeation rates, using two novel supported molten-salt membrane geometries. In both cases, the membranes comprise a solid support with laser-drilled pores, which are infiltrated with a highly CO2-selective molten carbonate salt. First, we fabricate an optically transparent single-crystal, single-pore model membrane by local laser drilling. By infiltrating the single pore with molten carbonate, monitoring the gas-liquid interface optically, and using image analysis on gas bubbles within the molten carbonate (because they change volume upon controlled changes in gas composition), we extract CO2 permeation rates with exceptional speed and precision. Additionally, in this arrangement, microstructural characterization is more straightforward and a sealant is not required, eliminating a major source of leakage. Furthermore, we demonstrate that the technique can be used to probe a previously unexplored driving force region, too low to access with conventional methods. Subsequently, we fabricate a leak-free tubular-supported molten-salt membrane with 1000 laser-drilled pores (infiltrated with molten carbonate) and employ a CO2-containing sweep gas to obtain permeation rates in a system that can be described with unprecedented precision. Together, the two approaches provide new ways to measure permeation rates with increased speed and at previously inaccesible conditions.
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All real processes, be they chemical, mechanical or electrical, are thermodynamically irreversible and therefore suffer from thermodynamic losses. Here, we report the design and operation of a chemical reactor capable of approaching thermodynamically reversible operation. The reactor was employed for hydrogen production via the water-gas shift reaction, an important route to 'green' hydrogen. The reactor avoids mixing reactant gases by transferring oxygen from the (oxidizing) water stream to the (reducing) carbon monoxide stream via a solid-state oxygen reservoir consisting of a perovskite phase (La0.6Sr0.4FeO3-δ). This reservoir is able to remain close to equilibrium with the reacting gas streams because of its variable degree of non-stoichiometry and thus develops a 'chemical memory' that we employ to approach reversibility. We demonstrate this memory using operando, spatially resolved, real-time, high-resolution X-ray powder diffraction on a working reactor. The design leads to a reactor unconstrained by overall chemical equilibrium limitations, which can produce essentially pure hydrogen and carbon dioxide as separate product streams.
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Amyloid-beta protein precursor (APP) and metabolite levels are altered in fragile X syndrome (FXS) patients and in the mouse model of the disorder, Fmr1KO mice. Normalization of APP levels in Fmr1KO mice (Fmr1KO /APPHET mice) rescues many disease phenotypes. Thus, APP is a potential biomarker as well as therapeutic target for FXS. Hyperexcitability is a key phenotype of FXS. Herein, we determine the effects of APP levels on hyperexcitability in Fmr1KO brain slices. Fmr1KO /APPHET slices exhibit complete rescue of UP states in a neocortical hyperexcitability model and reduced duration of ictal discharges in a CA3 hippocampal model. These data demonstrate that APP plays a pivotal role in maintaining an appropriate balance of excitation and inhibition (E/I) in neural circuits. A model is proposed whereby APP acts as a rheostat in a molecular circuit that modulates hyperexcitability through mGluR5 and FMRP. Both over- and under-expression of APP in the context of the Fmr1KO increases seizure propensity suggesting that an APP rheostat maintains appropriate E/I levels but is overloaded by mGluR5-mediated excitation in the absence of FMRP. These findings are discussed in relation to novel treatment approaches to restore APP homeostasis in FXS.
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Fragile X syndrome (FXS) is the most common form of inherited intellectual disability and the leading known genetic cause of autism. Fragile X mental retardation protein (FMRP), which is absent or expressed at substantially reduced levels in FXS, binds to and controls the postsynaptic translation of amyloid ß-protein precursor (AßPP) mRNA. Cleavage of AßPP can produce ß-amyloid (Aß), a 39-43 amino acid peptide mis-expressed in Alzheimer's disease (AD) and Down syndrome (DS). Aß is over-expressed in the brain of Fmr1(KO) mice, suggesting a pathogenic role in FXS. To determine if genetic reduction of AßPP/Aß rescues characteristic FXS phenotypes, we assessed audiogenic seizures (AGS), anxiety, the ratio of mature versus immature dendritic spines and metabotropic glutamate receptor (mGluR)-mediated long-term depression (LTD) in Fmr1(KO) mice after removal of one App allele. All of these phenotypes were partially or completely reverted to normal. Plasma Aß(1-42) was significantly reduced in full-mutation FXS males compared to age-matched controls while cortical and hippocampal levels were somewhat increased, suggesting that Aß is sequestered in the brain. Evolving therapies directed at reducing Aß in AD may be applicable to FXS and Aß may serve as a plasma-based biomarker to facilitate disease diagnosis or assess therapeutic efficacy.