Magnetic properties and specific heat of LaMn<SUB>1-x</SUB>Ti<SUB>x</SUB>O<SUB>3+&#948;</SUB> (0 &lt;x &#8804;0.2)

We present a magnetic study of the insulating perovskite LaMn1-xTixO3+&#948; (0&lt;x&#8804;0.2) including measurements of magnetization, susceptibility, and magnetic relaxation. The Curie temperature was found to decrease with increasing content of Ti. Two distinct magnetic transitions, irreversibility, non-exponential relaxation and aging effects confirm a reentrant spin-glass state for x=0.2. The time decay of the magnetization has an algebraic functional form for times up to 2 h. The specific heat also displays characteristic features of a spin-glass system by a linear low-temperature dependence and a broadened peak near the temperature of the reentrant transition

Continuous phase transition in mixed-valent manganite Nd0.6Pb0.4MnO3

The critical behaviour has been investigated in single crystalline Nd0.6Pb0.4MnO3 near the paramagnetic to ferromagnetic transition temperature (TC) by static magnetic measurements. The values of TC and the critical exponents β, γ and δ are estimated by analysing the data in the critical region. The exponent values are very close to those expected for 3D Heisenberg ferromagnets with short-range interactions. Specific heat measurements show a broad cusp at TC (i.e., exponent α<0) being consistent with Heisenberg-like behaviour

Early Patient-Centered Outcomes Research Experience With the Use of Telehealth to Address Disparities: Scoping Review

BackgroundHealth systems and providers across America are increasingly employing telehealth technologies to better serve medically underserved low-income, minority, and rural populations at the highest risk for health disparities. The Patient-Centered Outcomes Research Institute (PCORI) has invested US $386 million in comparative effectiveness research in telehealth, yet little is known about the key early lessons garnered from this research regarding the best practices in using telehealth to address disparities. ObjectiveThis paper describes preliminary lessons from the body of research using study findings and case studies drawn from PCORI seminal patient-centered outcomes research (PCOR) initiatives. The primary purpose was to identify common barriers and facilitators to implementing telehealth technologies in populations at risk for disparities. MethodsA systematic scoping review of telehealth studies addressing disparities was performed. It was guided by the Arksey and O’Malley Scoping Review Framework and focused on PCORI’s active portfolio of telehealth studies and key PCOR identified by study investigators. We drew on this broad literature using illustrative examples from early PCOR experience and published literature to assess barriers and facilitators to implementing telehealth in populations at risk for disparities, using the active implementation framework to extract data. Major themes regarding how telehealth interventions can overcome barriers to telehealth adoption and implementation were identified through this review using an iterative Delphi process to achieve consensus among the PCORI investigators participating in the study. ResultsPCORI has funded 89 comparative effectiveness studies in telehealth, of which 41 assessed the use of telehealth to improve outcomes for populations at risk for health disparities. These 41 studies employed various overlapping modalities including mobile devices (29/41, 71%), web-based interventions (30/41, 73%), real-time videoconferencing (15/41, 37%), remote patient monitoring (8/41, 20%), and store-and-forward (ie, asynchronous electronic transmission) interventions (4/41, 10%). The studies targeted one or more of PCORI’s priority populations, including racial and ethnic minorities (31/41, 41%), people living in rural areas, and those with low income/low socioeconomic status, low health literacy, or disabilities. Major themes identified across these studies included the importance of patient-centered design, cultural tailoring of telehealth solutions, delivering telehealth through trusted intermediaries, partnering with payers to expand telehealth reimbursement, and ensuring confidential sharing of private information. ConclusionsEarly PCOR evidence suggests that the most effective health system- and provider-level telehealth implementation solutions to address disparities employ patient-centered and culturally tailored telehealth solutions whose development is actively guided by the patients themselves to meet the needs of specific communities and populations. Further, this evidence shows that the best practices in telehealth implementation include delivery of telehealth through trusted intermediaries, close partnership with payers to facilitate reimbursement and sustainability, and safeguards to ensure patient-guided confidential sharing of personal health information

Análise fluido-dinâmica do escoamento em ensaio de permeabilidade ao ar de argamassas preparadas com cimento Portland de alto-forno Fluid-dynamic analysis of the flow in air permeability measurement of mortars prepared with blast-slag furnace Portland cement

O estudo dos fenômenos fluido-dinâmicos de escoamento em meios porosos tem sido de grande interesse por diversas áreas das ciências, de forma a se avaliar não só a permeabilidade do material, mas também analisar o comportamento do fluido permeante quando no interior destes materiais. Tratando-se de compósitos à base de cimento, a mensuração da permeabilidade torna-se fundamental para que sua durabilidade possa ser estimada, pois é a permeabilidade que controla a taxa de ingresso e movimentação de agentes deletérios no interior destes materiais. Dessa forma, diversas metodologias e equacionamentos matemáticos têm sido utilizados para prever a permeabilidade de materiais à base de cimento. No entanto, várias discrepâncias e disparidades nos resultados têm sido encontradas. Dentre as metodologias empregadas para mensurar a permeabilidade de meios porosos, encontra-se a desenvolvida por Thenoz, a qual tem demonstrado bons resultados em materiais à base de cimento. Dessa forma, este trabalho visa, por meio de ensaio de permeabilidade ao ar, realizado de acordo com a metodologia de Thenoz, avaliar o comportamento fluido-dinâmico do ar durante o ensaio de permeabilidade em argamassas. Para isto, foram utilizadas argamassas preparadas com dois tipos de cimento Portland (CP II E - 32 e CP III - 32), duas relações água/cimento (0,5 e 0,6) e ensaiadas em idades de 14 e 28 dias. Por meio dos resultados obtidos foi possível observar que durante o escoamento a compressibilidade do ar pode ser ignorada e o regime de escoamento pode ser considerado como laminar, demonstrando que a metodologia proposta por Thenoz e o equacionamento matemático empregado pode resultar em coeficientes de permeabilidade ao ar confiáveis, pois fenômenos e considerações que poderiam influenciar neste tipo de escoamento podem ser negligenciados.<br>Fluid-dynamic phenomena study in porous media flow has been of great interest for diverse areas of sciences. These studies not only have evaluated the permeability of porous media, but also to analyze the behavior of the fluid during the flow. Being about to the cement based materials, the measuring of the permeability becomes basic so that the durability of these can be estimate, therefore is the permeability that controls the rate of ingression and movement of deleterious agents inside these materials. Thus, diverse methodologies and mathematical equations have been used to foresee the permeability of cementitious materials, however, some discrepancies and nonsense in the results have been found. Amongst the used methodologies to measure the permeability of porous media, one meets developed it by Thenoz, which it has demonstrated good results in cement based materials. Thus, this work aims at, by means of assay of permeability to air, carried through in accordance with the methodology of Thenoz, to evaluate the fluid-dynamic behavior of air during the assay of permeability in mortars. For this, mortars prepared with two types of Portland cement of blast furnace (CP IIE-32 and CP III - 32), two relations water/cement (0.5 and 0.6) and ages of 14 and 28 days were used. By means of the gotten results it was possible to observe that during the draining the compressibility of air can be ignored, the regimen of draining can be considered as to plate, demonstrating that the methodology proposal for Thenoz and used mathematical equations can result in coefficients of trustworthy air permeability, therefore phenomena and considerations that could influence in this type of flow can be neglected, in accordance with what it is considered by literature