Donor/Acceptor Heterojunction Organic Solar Cells

The operation and the design of organic solar cells with donor/acceptor heterojunction structure and exciton blocking layer is outlined and results of their initial development and assessment are reported. Under halogen lamp illumination with 100 mW/cm2 incident optical power density, the devices exhibits an open circuit voltage VOC = 0.45 V, a short circuit current density JSC between 2 and 2.5 mA/cm2 with a fill factor FF ≈ 50%, an external quantum efficiency (electrons/s over incident photons/s) EQE ≈ 5% and a power conversion efficiency of about 0.5%. Measurements of the photoelectrical characteristics with time are also reported, confirming that non encapsulated organic solar cells have limited stability in ambient atmosphere

Generador de números pseudoaleatorios mediante el sistema numérico de residuos, estudio estadístico

Este trabajo estudia la implementación en hardware de nuevos generadores de números pseudoaleatorios (Pseudo Random Number Generators, PRNGs o Generadores de Números Pseudoaleatorios, GNPA), en lógica programable (Field Programmable Gate Arrays o FPGA). Se investiga el empleo del sistema numérico de residuos (Residue Number System o RNS) para incrementar la velocidad a la que los generadores producen los números aleatorios y para que posea una dinámica distinta a los generadores conocidos. El circuito propuesto ya se evaluó mediante tests básicos y el conjunto de tests desarrollados por George Marsaglia para su generador Diehard. El trabajo está organizado de la siguiente manera: comienza con la definición de sistemas determinísticos y aleatorios junto con una introducción a la denominada complejidad estadística y dos de las métricas propuestas, luego se describe el generador de números pseudoaleatorios propuesto junto la explicación de cada uno de los bloques que lo constituyen y finalmente se presentan los aportes y conclusiones del trabajo realizado.Centro de Técnicas Analógico-Digitale

A Low Complexity Sum-Subtract Decoding Algorithm for Non-Binary LDPC Codes over GF(q)

In this paper, we present a low complexity Sum-Subtract decoder for non-binary LDPC codes defined over GF(q). The performance of this decoding algorithm is similar to that of the Fast Fourier Transform Sum-Product algorithm usually utilized for decoding non-binary LDPC codes. It is a simplified algorithm that can be easily implemented on programmable logic technology such as FPGA devices because of its use of only additions and subtractions, avoiding the use of quotients and products, and of float point arithmetic. The algorithm yields a very low complexity programmable logic implementation of an NB-LDPC decoder with an excellent BER performance.Sociedad Argentina de Informática e Investigación Operativ

Desarrollo de un sistema integral de biotelemetría: monitorización remota de señales biológicas

En el presente trabajo se describe el prototipo de un sistema de telemetría para el monitoreo de señales biomédicas. El enlace físico entre la red y las mediciones entregadas por los sensores se realiza mediante luz infrarroja. Se comienza con una descripción del sistema realizado, tanto del hardware como del software. Se explica el tipo de red empleada, el protocolo de comunicación y la norma eléctrica en que se basa el sistema físico. Finalmente se explica la implementación de la base de datos realizada para el análisis de los datos adquiridos.Eje: Aplicaciones biomédicasRed de Universidades con Carreras en Informática (RedUNCI

Desarrollo de un sistema integral de biotelemetría: monitorización remota de señales biológicas

En el presente trabajo se describe el prototipo de un sistema de telemetría para el monitoreo de señales biomédicas. El enlace físico entre la red y las mediciones entregadas por los sensores se realiza mediante luz infrarroja. Se comienza con una descripción del sistema realizado, tanto del hardware como del software. Se explica el tipo de red empleada, el protocolo de comunicación y la norma eléctrica en que se basa el sistema físico. Finalmente se explica la implementación de la base de datos realizada para el análisis de los datos adquiridos.Eje: Aplicaciones biomédicasRed de Universidades con Carreras en Informática (RedUNCI

Diseño de un codificador ciclico programable para ser utilizado en comunicaciones infrarrojas interiores

Entre los factores más importantes que afectan a las comunicaciones infrarrojas interiores, están el ruido producido por la iluminación ambiental, la potencia infrarroja irradiada y la distancia entre el transmisor y el receptor infrarrojo. Esto provoca que la relación señal a ruido (SNR) en el receptor pueda variar considerablemente produciendo un aumento en los errores durante la transmisión. En este trabajo se expone el diseño de un codificador cíclico implementado con dispositivos programables de ALTERA, que produce una interesante mejora en el funcionamiento del enlace infrarrojo.Eje: Control y electrónicaRed de Universidades con Carreras en Informática (RedUNCI

Material quality characterization of CdZnTe substrates for HgCdTe epitaxy

Cd1-xZnxTe (CZT) substrates were studied to investigate their bulk and surface properties. Imperfections in CZT substrates affect the quality of Hg1-xCdxTe (MCT) epilayers deposited on them and play a role in limiting the performance of infrared (IR) focal plane arrays. CZT wafers were studied to investigate their bulk and surface properties. Transmission and surface x-ray diffraction techniques, utilizing both a conventional closed-tube x-ray source as well as a synchrotron radiation source, and IR transmission microspectroscopy, were used for bulk and surface investigation. Synchrotron radiation offers the capability to combine good spatial resolution and shorter exposure times than conventional x-ray sources, which allows for high-resolution mapping of relatively large areas in an acceptable amount of time. Information on the location of grain boundaries and precipitates was also obtained. The ultimate goal of this work is to understand the defects in CZT substrates and their effects on the performance and uniformity of MCT epilayers and then to apply this understanding to produce better infrared detectors

Investigation on Metal–Oxide Graphene Field-Effect Transistors With Clamped Geometries

In this work, we report on the design, fabrication and characterization of Metal-Oxide Graphene Field-effect Transistors (MOGFETs) exploiting novel clamped gate geometries aimed at enhancing the device transconductance. The fabricated devices employ clamped metal contacts also for source and drain, as well as an optimized graphene meandered pattern for source contacting, in order to reduce parasitic resistance. Our experimental results demonstrate that MOGFETs with the proposed structure show improved high frequency performance, in terms of maximum available gain and transition frequency values, as a consequence of the higher equivalent transconductance obtained

Dupilumab in the treatment of severe uncontrolled chronic rhinosinusitis with nasal polyps (CRSwNP): A multicentric observational Phase IV real-life study (DUPIREAL)

Background Chronic rhinosinusitis with nasal polyps (CRSwNP) is associated with significant morbidity and reduced health-related quality of life. Findings from clinical trials have demonstrated the effectiveness of dupilumab in CRSwNP, although real-world evidence is still limited. Methods This Phase IV real-life, observational, multicenter study assessed the effectiveness and safety of dupilumab in patients with severe uncontrolled CRSwNP (n = 648) over the first year of treatment. We collected data at baseline and after 1, 3, 6, 9, and 12 months of follow-up. We focused on nasal polyps score (NPS), symptoms, and olfactory function. We stratified outcomes by comorbidities, previous surgery, and adherence to intranasal corticosteroids, and examined the success rates based on current guidelines, as well as potential predictors of response at each timepoint. Results We observed a significant decrease in NPS from a median value of 6 (IQR 5–6) at baseline to 1.0 (IQR 0.0–2.0) at 12 months (p < .001), and a significant decrease in Sino-Nasal Outcomes Test-22 (SNOT-22) from a median score of 58 (IQR 49–70) at baseline to 11 (IQR 6–21; p < .001) at 12 months. Sniffin' Sticks scores showed a significant increase over 12 months (p < .001) compared to baseline. The results were unaffected by concomitant diseases, number of previous surgeries, and adherence to topical steroids, except for minor differences in rapidity of action. An excellent-moderate response was observed in 96.9% of patients at 12 months based on EPOS 2020 criteria. Conclusions Our findings from this large-scale real-life study support the effectiveness of dupilumab as an add-on therapy in patients with severe uncontrolled CRSwNP in reducing polyp size and improving the quality of life, severity of symptoms, nasal congestion, and smell

Combined fit to the spectrum and composition data measured by the Pierre Auger Observatory including magnetic horizon effects

The measurements by the Pierre Auger Observatory of the energy spectrum and mass composition of cosmic rays can be interpreted assuming the presence of two extragalactic source populations, one dominating the flux at energies above a few EeV and the other below. To fit the data ignoring magnetic field effects, the high-energy population needs to accelerate a mixture of nuclei with very hard spectra, at odds with the approximate E$^{-2}$ shape expected from diffusive shock acceleration. The presence of turbulent extragalactic magnetic fields in the region between the closest sources and the Earth can significantly modify the observed CR spectrum with respect to that emitted by the sources, reducing the flux of low-rigidity particles that reach the Earth. We here take into account this magnetic horizon effect in the combined fit of the spectrum and shower depth distributions, exploring the possibility that a spectrum for the high-energy population sources with a shape closer to E$^{-2}$ be able to explain the observations