Vertical and In-Plane Electronic Transport of Graphene Nanoribbon/Nanotube Heterostructures.

All-carbon systems have proven to present interesting transport properties and are often used in electronic devices. Motivated by recent resonant responses measured on graphene/fullerene junction, we propose coupled nanoribbons/carbon-nanotube heterostructures for use as charge filters and to allow tuned transport. These hybrid systems are engineered as a four-terminal device, and we explore multiple combinations of source and collector leads. The armchair-edge configuration results in midgap states when the transport is carried through top/bottom terminals. Such states are robust against the lack of perfect order on the tube and are revealed as sharp steps in the characteristic current curves when a bias potential is turned on. The zigzag-edge systems exhibit differential negative resistance, with features determined by the details of the hybrid structures.

Manipulation of Majorana bound states in proximity to a quantum ring with Rashba coupling.

The quest for Majorana zero modes in the laboratory is an active field of research in condensed matter physics. In this regard, there have been many theoretical proposals; however, their experimental detection remains elusive. In this article, we present a realistic setting by considering a quantum ring with Rashba spin-orbit coupling and threaded by a magnetic flux, in contact with a topological superconducting nanowire. We focus on spin-polarized persistent currents to assess the existence of Majorana zero modes. We find that the Rashba spin-orbit coupling allows for tuning the position of the zero energy crossings in the flux parameter space and has sizable effects on spin-polarized persistent currents. We believe that our results will contribute towards probing the existence of Majorana zero modes.

Left Ventricular Reconstruction Surgery in Candidates for Heart Transplantation.

OBJECTIVE: To report our center's experience in the surgical treatment of ventricular reconstruction, an effective and efficient technique that allows patients with end-stage heart failure of ischemic etiology to have clinical improvement and increased survival. METHODS: Observational, clinical-surgical, sequential, retrospective study. Patients with ischemic cardiomyopathy and left ventricular aneurysm were attended at the Heart Failure, Ventricular Dysfunction and Cardiac Transplant outpatient clinic of the Dante Pazzanese Cardiology Institute, from January 2010 to December 2016. Data from 34 patients were collected, including systemic arterial hypertension, ejection fraction, New York Heart Association (NYHA) functional classification (FC), European System for Cardiac Operative Risk Evaluation (EuroSCORE) II value, Society of Thoracic Surgeons (STS) score, ventricular reconstruction technique, and survival. RESULTS: Overall mortality of 14.7%, with hospital admission being 8.82% and late death being 5.88%. Total survival rate at five years of 85.3%. In the preoperative phase, NYHA FC was Class I in five patients, II in 18, III in eight, and IV in three vs. NYHA FC Class I in 17 patients, II in eight, III in six, and IV in three, in the postoperative period. EuroSCORE II mean value was 6.29, P≤0.01; hazard ratio (HR) 1.16 (95% confidence interval [CI] 1.02-1.31). STS mortality/morbidity score mean value was 18.14, P≤0.004; HR 1.19 (95% CI 1.05-1.33). Surgical techniques showed no difference in survival among Dor 81% vs. Jatene 91.7%. CONCLUSION: Surgical treatment of left ventricular reconstruction in candidates for heart transplantation is effective, efficient, and safe, providing adequate survival.

Left ventricular reconstruction surgery in candidates for heart transplantation

OBJECTIVE: To report our center's experience in the surgical treatment of ventricular reconstruction, an effective and efficient technique that allows patients with end-stage heart failure of ischemic etiology to have clinical improvement and increased survival. METHODS: Observational, clinical-surgical, sequential, retrospective study. Patients with ischemic cardiomyopathy and left ventricular aneurysm were attended at the Heart Failure, Ventricular Dysfunction and Cardiac Transplant outpatient clinic of the Dante Pazzanese Cardiology Institute, from January 2010 to December 2016. Data from 34 patients were collected, including systemic arterial hypertension, ejection fraction, New York Heart Association (NYHA) functional classification (FC), European System for Cardiac Operative Risk Evaluation (EuroSCORE) II value, Society of Thoracic Surgeons (STS) score, ventricular reconstruction technique, and survival. RESULTS: Overall mortality of 14.7%, with hospital admission being 8.82% and late death being 5.88%. Total survival rate at five years of 85.3%. In the preoperative phase, NYHA FC was Class I in five patients, II in 18, III in eight, and IV in three vs. NYHA FC Class I in 17 patients, II in eight, III in six, and IV in three, in the postoperative period. EuroSCORE II mean value was 6.29, P

Magnetic Otto Engine for an Electron in a Quantum Dot: Classical and Quantum Approach.

We studied the performance of classical and quantum magnetic Otto cycle with a working substance composed of a single quantum dot using the Fock-Darwin model with the inclusion of the Zeeman interaction. Modulating an external/perpendicular magnetic field, in the classical approach, we found an oscillating behavior in the total work extracted that was not present in the quantum formulation.We found that, in the classical approach, the engine yielded a greater performance in terms of total work extracted and efficiency than when compared with the quantum approach. This is because, in the classical case, the working substance can be in thermal equilibrium at each point of the cycle, which maximizes the energy extracted in the adiabatic strokes.

Stacking change in MoS2 bilayers induced by interstitial Mo impurities.

We use a theoretical approach to reveal the electronic and structural properties of molybdenum impurities between MoS2 bilayers. We find that interstitial Mo impurities are able to reverse the well-known stability order of the pristine bilayer, because the most stable form of stacking changes from AA' (undoped) into AB' (doped). The occurrence of Mo impurities in different positions shows their split electronic levels in the energy gap, following octahedral and tetrahedral crystal fields. The energy stability is related to the accommodation of Mo impurities compacted in hollow sites between layers. Other less stable configurations for Mo dopants have larger interlayer distances and band gaps than those for the most stable stacking. Our findings suggest possible applications such as exciton trapping in layers around impurities, and the control of bilayer stacking by Mo impurities in the growth process.

Optoelectronic Properties of Van Der Waals Hybrid Structures: Fullerenes on Graphene Nanoribbons.

The search for new optical materials capable of absorbing light in the frequency range from visible to near infrared is of great importance for applications in optoelectronic devices. In this paper, we report a theoretical study of the electronic and optical properties of hybrid structures composed of fullerenes adsorbed on graphene and on graphene nanoribbons. The calculations are performed in the framework of the density functional theory including the van der Waals dispersive interactions. We found that the adsorption of the C 60 fullerenes on a graphene layer does not modify its low energy states, but it has strong consequences for its optical spectrum, introducing new absorption peaks in the visible energy region. The optical absorption of fullerenes and graphene nanoribbon composites shows a strong dependence on photon polarization and geometrical characteristics of the hybrid systems, covering a broad range of energies. We show that an external electric field across the nanoribbon edges can be used to tune different optical transitions coming from nanoribbon-fullerene hybridized states, which yields a very rich electro-absorption spectrum for longitudinally polarized photons. We have carried out a qualitative analysis on the potential of these hybrids as possible donor-acceptor systems in photovoltaic cells.

[Functional geriatric assessment in primary health care]. / Criterios de valoración geriátrica integral en adultos mayores con dependencia moderada y severa en Centros de Atención Primaria en Chile.

The functional assessment of moderately or severely dependent older people encompasses social, psychological and biological aspects that may influence their quality of life and their degree of independence. This paper reviews the global geriatric assessment that should be performed in primary health care (PHC) for moderately or severely dependent older people. Since 2012 in PHC in Chile, the norm establishes that the degree of independence of older people should be assessed using the Barthel scale and caregiver stress should be evaluated using Zarit scale. People with severe disability should receive home care. We recommend to evaluate also cognitive aspects using the Mini-Mental State Examination (MMSE) to Barthel Index or using the Functional Independence Measure (FIM), since they are closely associated with functional capacity.

Criterios de valoración geriátrica integral en adultos mayores con dependencia moderada y severa en Centros de Atención Primaria en Chile / Functional geriatric assessment in primary health care

The functional assessment of moderately or severely dependent older people encompasses social, psychological and biological aspects that may influence their quality of life and their degree of independence. This paper reviews the global geriatric assessment that should be performed in primary health care (PHC) for moderately or severely dependent older people. Since 2012 in PHC in Chile, the norm establishes that the degree of independence of older people should be assessed using the Barthel scale and caregiver stress should be evaluated using Zarit scale. People with severe disability should receive home care. We recommend to evaluate also cognitive aspects using the minimental state examination (MMSE) to Barthel Index or using the Functional Independence Measure (FIM), since they are closely associated with functional capacity.

Valoración del estado funcional de adultos mayores con dependencia moderada y severa pertenecientes a un centro de salud familiar / Functional status evaluation of older adults with moderate and severe unit belonging to a family health center / Avaliação do estado funcional de idosos com dependência moderada e severa pertencentes ao centro de saúde familiar

El propósito de este estudio fue valorar el estado funcional de adultos mayores con dependencia moderada y severa pertenecientes a un Centro de Salud Familiar, aplicando escalas que evalúan actividades de la vida diaria, nivel cognitivo, nivel educacional y carga del cuidador. Se evaluó a 55 sujetos categorizados con dependencia moderada y severa. Se utilizó el Índice Katz para determinar el nivel de dependencia; Medida de Independencia Funcional (FIM) para la funcionalidad y asistencia dada por una tercera persona; Índice de Barthel para valorar la independencia; Minimental abreviado (MMSE) para el estado cognitivo y la carga del cuidador mediante la Escala de Zarit. La edad media fue de 84,4±7,8 años (74,5% género femenino y 25,5% género masculino). El 45% fue clasificado con dependencia severa total según el Índice de Barthel. Los hombres obtuvieron mayores puntajes en el Índice de Barthel y FIM. El 75% presentó deterioro cognitivo según el MMSE con una media de 7,2±5,3 puntos. El 85% de los cuidadores eran del género femenino y el 49% de éstos presentaban sobrecarga intensa. Se obtuvo una correlación significativa entre FIM motor e Índice de Barthel (r=0,9710), FIM cognitivo y MMSE (r=0,8148), MMSE y nivel educacional (r=0,6537). No se encontró correlación entre edad y cognición e independencia funcional. Según los datos obtenidos, la mayoría de los adultos mayores con dependencia moderada y severa presentan alteraciones motoras y cognitivas, estando correlacionadas al nivel educacional del sujeto.

Este estudo tem como objetivo avaliar, por meio de escalas que investigam atividades cotidianas e os níveis cognitivo, educacional e também a sobrecarga do cuidador, o estado funcional de idosos com dependência moderada e severa pertencentes ao Centro de Saúde Familiar, da cidade de Talca, Chile. Cinquenta e cinco indivíduos foram avaliados categorizados com dependência moderada e severa. Para isso, o estudo utilizou os seguintes métodos: Índice de Katz para determinar o nível de dependência; Medida de Independência Funcional (FIM) para determinar a funcionalidade e assistência fornecida por uma terceira pessoa; o Índice de Barthel para analisar a independência; e o Miniexame do Estado Mental abreviado (MMSE) para avaliar o estado cognitivo e a sobrecarga do cuidador por meio da Escala de Zarit. A média de idade era de 84,4±7,8 anos (74,5% pertencente ao gênero feminino e 25,5% ao masculino). Tendo como base o Índice de Barthel 45% foram classificados com dependência severa total. Os homens obtiveram pontuações maiores no Índice de Barthel e no FIM. 75% apresentaram déficit cognitivo de acordo com o MMSE sendo a média de 7,2±5,3 pontos. Dos cuidadores, 85% eram do gênero feminino e, destes, 49% apresentavam sobrecarga intensa. A correlação significativa obtida foi de r=0,9710 entre FIM motor e Índice de Barthel; r=0,8148 entre FIM cognitivo e MMSE; e r=0,6537 entre MMSE e nível educacional. Não foram encontradas correlações entre idade e cognição e independência funcional. De acordo com os dados obtidos, a maioria dos idosos com dependência moderada e severa apresenta alterações motoras e cognitivas, relacionadas ao nível educacional do indivíduo.

The purpose of this study was to assess the functional status of older adults with moderate and severe dependence from a family health center, applying scales to evaluate activities of daily living, cognitive level, educational level and caregiver burden. We evaluated 55 older adults with moderate and severe dependence. The Katz Index was used to determine the level of dependence, the Functional Independence Measure (FIM) was used for functionality and assistance provided by a third person, the Barthel Index was used to assess the independence, the Mini Mental State Examination (MMSE) was used for cognitive status and the Zarit scale was used for caregiver burden. The mean age was 84.4±7.8 years , and 74.5% of the subjects were female (25.5% male). According to the Barthel Index, 45% were classified with severe dependence; men had higher scores on the Barthel index and FIM. Cognitive impairment was present in 75% of the subjects according to MMSE, with a mean of 7.2±5.3 points. Women represented 85% of caregivers and 49% of these had greater burden. We obtained a significant correlation between motor FIM and Barthel Index (r=0.9710), cognitive FIM and MMSE (r=0.8148), and MMSE and educational level (r=0.6537). There was no correlation between age and cognition or functional independence. According to the data, most older adults with moderate and severe dependence have motor and cognitive impairment, which are correlated to the educational level of the subject.

Oestradiol and progesterone differentially alter cytoskeletal protein expression and flame cell morphology in Taenia crassiceps.

We examined the effects of oestradiol (E2) and progesterone (P4) on cytoskeletal protein expression in the helminth Taenia crassiceps - specifically actin, tubulin and myosin. These proteins assemble into flame cells, which constitute the parasite excretory system. Total protein extracts were obtained from E2- and P4-treated T. crassiceps cysticerci and untreated controls, and analysed by one- and two-dimensional protein electrophoresis, flow cytometry, immunofluorescence and videomicroscopy. Exposure of T. crassiceps cysticerci to E2 and P4 induced differential protein expression patterns compared with untreated controls. Changes in actin, tubulin and myosin expression were confirmed by flow cytometry of parasite cells and immunofluorescence. In addition, parasite morphology was altered in response to E2 and P4 versus controls. Flame cells were primarily affected at the level of the ciliary tuft, in association with the changes in actin, tubulin and myosin. We conclude that oestradiol and progesterone act directly on T. crassiceps cysticerci, altering actin, tubulin and myosin expression and thus affecting the assembly and function of flame cells. Our results increase our understanding of several aspects of the molecular crosstalk between host and parasite, which might be useful in designing anthelmintic drugs that exclusively impair parasitic proteins which mediate cell signaling and pathogenic reproduction and establishment.

Fano-Kondo and the Kondo box regimes crossover in a quantum dot coupled to a quantum box.

In this work, we study the Kondo effect of a quantum dot (QD) connected to leads and to a discrete set of one-particle states provided by a quantum box represented by a quantum ring (QR) pierced by a magnetic flux side attached to the QD. The interplay between the bulk Kondo effect and the so-called Kondo box regime is studied. In this system the QR energies can be continuously modified by the application of the magnetic field. The crossover between these two regimes is analyzed by changing the connection of the QD to the QR from the weak to the strong coupling regime. In the weak coupling regime, the differential conductance develops a sequence of Fano-Kondo anti-resonances due to destructive interference between the discrete quantum ring levels and the conducting Kondo channel provided by the leads. In the strong coupling regime the differential conductance has very sharp resonances when one of the Kondo discrete sub-levels characterizing the Kondo box is tuned by the applied potential. The conductance, the current fluctuations and the Fano coefficient result as being the relevant physical magnitudes to be analyzed to reveal the physical properties of these two Kondo regimes and the crossover region between them. The results were obtained by using the slave boson mean field theory (SBMFT).