23 research outputs found

    Signatures of topological phase transitions in higher Landau levels of HgTe/CdTe quantum wells from an information theory perspective

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    We analyze the structure of low energy Hamiltonian eigenstates in zincblende heterostructures (like HgTe/CdTe quantum wells) near the gamma point, under magnetic fields, to characterize topological phase transitions (TPT) under an information-theoretic perspective. Using information markers like entanglement, quantum fluctuations, fidelity susceptibility, participation ration, area in phase space, etc., we realize that higher Landau levels (LL) feel the topological phase transition slightly displaced with regard to the edge state, thus leading to the concept of ‘‘higher Landau level |n| > 0 TPT’’, as ‘‘echoes’’ of the standard edge state n = 0 TPT. We compute the critical magnetic field and the critical HgTe layer thickness at which these information measures of higher Landau levels undergo a structural change.PGC2018-097831-B-I00UHU-1262561 and FQM-381Universidad de Granada / CBU

    Faraday rotation and transmittance as markers of topological phase transitions in 2D materials

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    We analyze the magneto-optical conductivity (and related magnitudes like transmittance and Faraday rotation of the irradiated polarized light) of some elemental twodimensional Dirac materials of group IV (graphene analogues, buckled honeycomb lattices, like silicene, germanene, stannane, etc.), group V (phosphorene), and zincblende heterostructures (like HgTe/CdTe quantum wells) near the Dirac and gamma points, under out-of-plane magnetic and electric fields, to characterize topological-band insulator phase transitions and their critical points. We provide plots of the Faraday angle and transmittance as a function of the polarized light frequency, for different external electric and magnetic fields, chemical potential, HgTe layer thickness and temperature, to tune the material magneto-optical properties. We have shown that absortance/transmittance acquires extremal values at the critical point, where the Faraday angle changes sign, thus providing fine markers of the topological phase transition. In the case of non-topological materials as phosphorene, a minimum of the transmittance is also observed due to the energy gap closing by an external electric field.ConsejerĂ­a de EconomĂ­a, InnovaciĂłn, Ciencia y Empleo, Junta de AndalucĂ­a (through Organization: ConsejerĂ­a de EconomĂ­a InnovaciĂłn Ciencia y Empleo)Ministerio de Ciencia e InnovaciĂłnUniversidad Nacional AutĂłnoma de MĂ©xico / National Autonomous University of Mexico [UNAM

    Lipoprotein(A) Concentrations In Rheumatoid Arthritis On Biologic Therapy: Results From The Cardiovascular In Rheumatology [Carma] Study Project

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    Background Plasma concentrations of lipoprotein (a) (Lp(a)), a lipoprotein with atherogenic and thrombogenic properties, have a strong genetic basis, although high concentrations of Lp(a) have also been reported in the context of inflammation, as in rheumatoid arthritis (RA). Few studies evaluate the impact of biologic therapies (BT) on Lp(a) in RA, taking into account that with these new therapies a better control of inflammation is achieved. Objective The aim of the study was to evaluate the plasma concentrations of Lp(a) in Spanish RA patients on BT attending rheumatology outpatient clinics. Methods Baseline analysis of the CARdiovascular in rheuMAtology project, a 10-year prospective study, evaluating the risk of cardiovascular events in RA and other forms of inflammatory arthritis. RA patients were classified according to treatment: no biologic, anti-tumor necrosis factor, anti-interleukin-6 receptor tocilizumab (TCZ), and other biologic (rituximab or abatacept). A model of linear multivariate regression was built in which the dependent variable was Lp(a) concentration and the explanatory variable was BT. The model was adjusted for confounding factors. Results Seven hundred and seventy-five RA patients were analyzed. Plasma concentrations of total cholesterol and triglyceride were significantly higher in TCZ-treated patients. Nevertheless, no significant difference in the atherogenic index between TCZ-treated patients and patients without BT was found. After adjusting for confounding factors, patients with BT had lower concentrations of Lp(a) than those without BT; however, only TCZ-treated patients achieved statistically significant differences (?: ?0.303, 95% confidence interval: ?0.558 to ?0.047; P = .02). Conclusions RA patients treated with TCZ show lower plasma concentrations of Lp(a) compared with patients without BT.This project has been supported by an unrestricted grant from Abbvie, Spain. The design, analysis, interpretation of results, and preparation of the article have been done independently of Abbvie. Dr González-Gay's studies have been supported by grants from “Fondo de Investigaciones Sanitarias” PI06/0024, PS09/00748, and PI12/00060 and RD12/0009/0013 (RIER) from “Instituto de Salud Carlos III” (ISCIII) (Spain)

    A Safe GDNF and GDNF/BDNF Controlled Delivery System Improves Migration in Human Retinal Pigment Epithelial Cells and Survival in Retinal Ganglion Cells: Potential Usefulness in Degenerative Retinal Pathologies

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    We assessed the sustained delivery effect of poly (lactic-co-glycolic) acid (PLGA)/vitamin E (VitE) microspheres (MSs) loaded with glial cell-derived neurotrophic factor (GDNF) alone (GDNF-MSs) or combined with brain-derived neurotrophic factor (BDNF; GDNF/BDNF-MSs) on migration of the human adult retinal pigment epithelial cell-line-19 (ARPE-19) cells, primate choroidal endothelial (RF/6A) cells, and the survival of isolated mouse retinal ganglion cells (RGCs). The morphology of the MSs, particle size, and encapsulation efficiencies of the active substances were evaluated. In vitro release, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell viability, terminal deoxynucleotidyl transferase (TdT) deoxyuridine dUTP nick-end labelling (TUNEL) apoptosis, functional wound healing migration (ARPE-19; migration), and (RF/6A; angiogenesis) assays were conducted. The safety of MS intravitreal injection was assessed using hematoxylin and eosin, neuronal nuclei (NeuN) immunolabeling, and TUNEL assays, and RGC in vitro survival was analyzed. MSs delivered GDNF and co-delivered GDNF/BDNF in a sustained manner over 77 days. The BDNF/GDNF combination increased RPE cell migration, whereas no effect was observed on RF/6A. MSs did not alter cell viability, apoptosis was absent in vitro, and RGCs survived in vitro for seven weeks. In mice, retinal toxicity and apoptosis was absent in histologic sections. This delivery strategy could be useful as a potential co-therapy in retinal degenerations and glaucoma, in line with future personalized long-term intravitreal treatment as different amounts (doses) of microparticles can be administered according to patients’ needs

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Convalescent Plasma for COVID-19: A multicenter, randomized clinical trial

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    Background: Passive immunotherapy with convalescent plasma (CP) is a potential treatment for COVID-19 for which evidence from controlled clinical trials is lacking. Methods: We conducted a multi-center, randomized clinical trial in patients hospitalized for COVID-19. All patients received standard of care treatment, including off-label use of marketed medicines, and were randomized 1:1 to receive one dose (250-300 mL) of CP from donors with IgG anti-SARS-CoV-2. The primary endpoint was the proportion of patients in categories 5, 6 or 7 of the COVID-19 ordinal scale at day 15. Results: The trial was stopped after first interim analysis due to the fall in recruitment related to pandemic control. With 81 patients randomized, there were no patients progressing to mechanical ventilation or death among the 38 patients assigned to receive plasma (0%) versus 6 out of 43 patients (14%) progressing in control arm. Mortality rates were 0% vs 9.3% at days 15 and 29 for the active and control groups, respectively. No significant differences were found in secondary endpoints. At inclusion, patients had a median time of 8 days (IQR, 6-9) of symptoms and 49,4% of them were positive for anti-SARS-CoV-2 IgG antibodies. Conclusions: Convalescent plasma could be superior to standard of care in avoiding progression to mechanical ventilation or death in hospitalized patients with COVID-19. The strong dependence of results on a limited number of events in the control group prevents drawing firm conclusions about CP efficacy from this trial. (Funded by Instituto de Salud Carlos III; NCT04345523).This research is funded by the Government of Spain, Ministry of Science and Innovation, Instituto de Salud Carlos III, grant number COV20/00072 (Royal Decree-Law 8/2020, of 17 March, on urgent extraordinary measures to deal with the economic and social impact of COVID-19), co-financed by the European Regional Development Fund (FEDER) ‘‘A way to make Europe’’ and supported by SCReN (Spanish Clinical Research Network), ISCIII, project PT17/0017/0009. Clinical trial insurance coverage was kindly donated by MARCH RS CorredurĂ­a de Seguros y Reaseguros. Mikel Mancheño-Losa holds a "RĂ­o Hortega" research contract (expte. CM19/00226N

    Habilidades Sociais Educativas Parentais e comportamentos de pré-escolares Parental Social Educational Skills and behavior of preschoolers

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    O estudo teve por objetivos, a partir dos relatos de 20 mĂŁes de crianças com problemas de comportamento (Grupo clĂ­nico) e de 20 mĂŁes de crianças sem problemas de comportamento (Grupo nĂŁo clĂ­nico): a) comparar as freqĂŒĂȘncias das habilidades sociais e dos problemas de comportamento das crianças; b) descrever as situaçÔes em que as crianças apresentavam os comportamentos problema e socialmente habilidosos; c) descrever os comportamentos das mĂŁes diante dos comportamentos dos filhos; d) descrever os comportamentos dos filhos diante dos comportamentos maternos. PrĂ©-escolares foram selecionados por professoras que responderam a uma escala e os dados foram coletados atravĂ©s de entrevista e de escala com as mĂŁes. Os resultados indicaram que as crianças do Grupo nĂŁo clĂ­nico apresentaram mais habilidades sociais e menos problemas de comportamento externalizantes que as crianças do Grupo clĂ­nico. As mĂŁes do Grupo nĂŁo clĂ­nico relataram mais Habilidades Sociais Educativas Parentais de expressĂŁo de sentimentos e enfrentamento, e Comunicação e menos prĂĄticas negativas, que as mĂŁes do Grupo clĂ­nico.<br>The study had for objectives, from the reports of 20 mothers of children with behavior problems (Clinical group) and 20 mothers of children without behavior problems (Non-clinical group): a) compare the frequencies of social skills and behavior problems of children; b) describe the situations where the children had behavior problems and social skills; c) describe the behaviors of mothers face behaviors of the children; d) describe the behaviors of children ahead of maternal behaviors. Pre-school they were selected age by teachers who responded to a scale and who were collected through interview and scale with the mothers. The results indicated that children of Non-clinical group had more social skills and fewer externalizing behavior problems than children of the Clinical group. The mothers in the Non-clinical group reported more Parental Social Educational Skills expression of feelings and coping and Communication and less negative parenting practices, than mothers of children with behavior problems
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