914 research outputs found
Gradual transition from insulator to semimetal of CaEuB with increasing Eu concentration
The local environment of Eu (, ) in
CaEuB () is investigated by
means of electron spin resonance (ESR). For the spectra show
resolved \textit{fine} and \textit{hyperfine} structures due to the cubic
crystal \textit{electric} field and nuclear \textit{hyperfine} field,
respectively. The resonances have Lorentzian line shape, indicating an
\textit{insulating} environment for the Eu ions. For , as increases, the ESR lines broaden due to local
distortions caused by the Eu/Ca ions substitution. For , the lines broaden further and the spectra gradually change from
Lorentzian to Dysonian resonances, suggesting a coexistence of both
\textit{insulating} and \textit{metallic} environments for the Eu ions.
In contrast to CaGdB, the \textit{fine} structure is still
observable up to . For the \textit{fine} and
\textit{hyperfine} structures are no longer observed, the line width increases,
and the line shape is purely Dysonian anticipating the \textit{semimetallic}
character of EuB. This broadening is attributed to a spin-flip scattering
relaxation process due to the exchange interaction between conduction and
Eu electrons. High field ESR measurements for
reveal smaller and anisotropic line widths, which are attributed to magnetic
polarons and Fermi surface effects, respectively.Comment: Submitted to PR
Homeless persons and migrants in precarious housing conditions and COVID-19 pandemic: peculiarities and prevention strategies
Homeless persons and migrants in precarious housing conditions are vulnerable populations that have been peculiarly impacted by the Coronavirus Disease 19 (COVID-19) pandemic. These populations are more at risk of contracting COVID-19 as they often find it difficult to adhere to public health directives and, if exposed, may be more susceptible to illness or death due to the higher prevalence of underlying physical and mental comorbidities compared to the general population. In addition, vulnerable populations may have limited access to essential diagnostics and treatments, thus leading to untreated COVID-19 cases and their development into more severe forms. Health, social and government agencies should collaborate to develop services that support these communities, in accordance with the World Health Organization principles. Migrant and homeless centers have a central role, as they provide a significant contribution to prevent infection spread and favor access to early medical treatment to those affected, thus preventing more severe forms of infection
Silica passivated conjugated polymer nanoparticles for biological imaging applications
Colorectal and prostate cancers are major causes of cancer-related death, with early detection key to increased survival. However, as symptoms occur during advanced stages and current diagnostic methods have limitations, there is a need for new fluorescent probes that remain bright, are biocompatible and can be targeted. Conjugated polymer nanoparticles have shown great promise in biological imaging due to their unique optical properties. We have synthesised small, bright, photo-stable CN-PPV, nanoparticles encapsulated with poloxamer polymer and a thin silica shell. By incubating the CN-PPV silica shelled cross-linked (SSCL) nanoparticles in mammalian (HeLa) cells; we were able to show that cellular uptake occurred. Uptake was also shown by incubating the nanoparticles in RWPE-1, WPE1-NB26 and WPE1- NA22 prostate cancer cell lines. Finally, HEK cells were used to show the particles had limited cytotoxicity
Assessment of Alternative Building Materials in the Exterior Walls for Reduction of Operational Energy and CO2 Emissions (Case study: A typical residential building in Tehran)
Health and social conditions of children living in disadvantaged neighborhoods in the city of Rome, Italy
OBJECTIVE: The number of children living in socio-economically disadvantaged neighborhoods in developed countries is constantly growing, resulting in important implications for children's development, physical and psychological health and increased future disparities. In this study, we explored several key elements of children living in poor neighborhoods, such as demographic characteristics, access to public health assistance and school, and availability of housing and basic hygienic conditions.PATIENTS AND METHODS: The study included 711 children aged 0-17 years referring to primary care services in the suburbs of the city of Rome, Italy.RESULTS: Most children were born in Italy, while almost none of their parents were. Nearly 60% of the children did not have access to basic pediatric care, causing possible misdiagnosis and delayed treatment for acute and chronic conditions. A smaller percentage of the children did not have access to basic housing (8%) and hygienic facilities, such as heating, running water, and refrigerator (3.2%), leading to malnutrition, isolation and poor physical and psychological development.CONCLUSIONS: This study confirms a critical condition for children living in disadvantaged neighborhoods, whose vulnerability is further worsened by the limited access to paediatric health assistance and, in some cases, to basic facilities with a severe impact on their physical and psychological development
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