Publications by authors named "Roldan J"

Objectives: The objective of this study was to evaluate the effect of autologous fat grafting in patients with juvenile localized scleroderma with facial involvement.

Methods: We retrospectively studied patients with juvenile localized scleroderma who were followed at the Hamburg Center for Pediatric and Adolescent Rheumatology at least 6 months post-operative follow-up and received at least one autologous fat transplantation for a facial lesion. Autologous fat grafting was conducted independent of disease-modifying treatment and/or disease activity.

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Background: Intensive care to facilitate organ donation (ICOD) involves the initiation or continuation of intensive care for patients with devastating brain injury for donation purposes. In the Spanish system, relatives undergo an early interview to request consent for this procedure. If they consent, a waiting time is agreed upon in the expectation that death by neurological criteria occurs and donation after brain death takes place.

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The drift characteristics of valence change memory (VCM) devices have been analyzed through both experimental analysis and 3D kinetic Monte Carlo (kMC) simulations. By simulating six distinct low-resistance states (LRS) over a 24-hour period at room temperature, we aim to assess the device temporal stability and retention. Our results demonstrate the feasibility of multi-level operation and reveal insights into the conductive filament (CF) dynamics.

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The order Testudines comprises some of the most endangered groups of vertebrates. Under specific circumstances, infectious and parasitic diseases may affect the survival and fecundity of these animals, potentially threatening Testudines populations. In Sardinia, besides the three species of tortoises present in the wild (Testudo hermanni, Testudo graeca and Testudo marginata), many others are kept as pets.

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Tuberous sclerosis complex (TSC) and autosomal dominant polycystic kidney disease (ADPKD) are genetically distinct disorders typically associated with pathogenic variants in TSC1 and TSC2 for the former and PKD1 and PKD2 for the latter. TSC2 and PKD1 lie adjacent to each other, and large deletions comprising both genes lead to TSC2/PKD1 contiguous gene deletion syndrome (CGS). In this study, we describe a young female patient exhibiting symptoms of TSC2/PKD1 CGS in which genetic analysis disclosed two noncontiguous partial gene deletions in TSC2 and PKD1 that putatively are responsible for the manifestations of the syndrome.

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Wild ungulates are expanding in range and number worldwide leading to an urgent need to manage their populations to minimize conflicts and promote coexistence with humans. In the metropolitan area of Barcelona (MAB), wild boar is the main wildlife species causing a nuisance, from traffic accidents to health risks. Selective harvesting of specific sex and age classes and reducing anthropogenic food resources would be the most efficient approach to dealing with overpopulation.

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A new statistical analysis is presented to assess cycle-to-cycle variability in resistive memories. This method employs two-dimensional (2D) distributions of parameters to analyse both set and reset voltages and currents, coupled with a 2D coefficient of variation (CV). This 2D methodology significantly enhances the analysis, providing a more thorough and comprehensive understanding of the data compared to conventional one-dimensional methods.

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Memristors are devices in which the conductance state can be alternately switched between a high and a low value by means of a voltage scan. In general, systems involving a chemical inductor mechanism as solar cells, asymmetric nanopores in electrochemical cells, transistors, and solid state memristive devices, exhibit a current increase and decrease over time that generates hysteresis. By performing small signal ac impedance spectroscopy, we show that memristors, or any other system with hysteresis relying on the conductance modulation effect, display intrinsic dynamic inductor-like and capacitance-like behaviours in specific input voltage ranges.

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Article Synopsis
  • Artificial Intelligence (AI) is getting much better thanks to deep learning, which uses lots of simple computer units working together.
  • Traditional computers have trouble moving data quickly, so new methods like using memristors as memory devices can help solve this problem by being more efficient and powerful.
  • This work explains how memristive neural networks work, their design options, and offers guidance for those interested in studying or improving these new technologies.
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Resistive switching devices based on the Au/Ti/TiO/Au stack were developed. In addition to standard electrical characterization by means of - curves, scanning thermal microscopy was employed to localize the hot spots on the top device surface (linked to conductive nanofilaments, CNFs) and perform in-operando tracking of temperature in such spots. In this way, electrical and thermal responses can be simultaneously recorded and related to each other.

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A 3D simulation of conductive nanofilaments (CNFs) in multilayer hexagonal-BN memristors is performed. To do so, a simulation tool based on circuit breakers is developed including for the first time a 3D resistive network. The circuit breakers employed can be modeled with two, three and four resistance states; in addition, a series resistance and a module to account for quantum effects, by means of the quantum point contact model, are also included.

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Background: Previous retrospective studies suggest a good diagnostic performance of F-fluorodeoxyglucose positron emission tomography (F-FDG-PET)/computed tomography (CT) in left ventricular assist device (LVAD) infections. Our aim was to prospectively evaluate the role of PET/CT in the characterization and impact on clinical management of LVAD infections.

Methods: A total of 40 patients (aged 58 [53-62] years) with suspected LVAD infection and 5 controls (aged 69 [64-71] years) underwent F-FDG-PET/CT.

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We characterize TiN/Ti/HfO/TiN memristive devices for neuromorphic computing. We analyze different features that allow the devices to mimic biological synapses and present the models to reproduce analytically some of the data measured. In particular, we have measured the spike timing dependent plasticity behavior in our devices and later on we have modeled it.

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A preliminary exploration of the physiology and morphology of the zebrafish embryo (ZFE) during the late-blastula and early-gastrula stages through its electrical properties was performed, applying the electrorotation (ROT) technique. This method, based on induced polarizability at the interfaces, was combined with an analytical spherical shell model to obtain the best fit of empirical data and the desired information, providing a means of understanding the role of different membranes. Suspended in two solutions of low conductivity, the major compartments of the ZFE were electrically characterized, considering morphological data from both observed records and data from the literature.

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Objectives: Natural language processing (NLP) algorithms can interpret unstructured text for commonly used terms and phrases. Pancreatic pathologies are diverse and include benign and malignant entities with associated histologic features. Creating a pancreas NLP algorithm can aid in electronic health record coding as well as large database creation and curation.

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Cervical cancer represents a global concern with 604,000 new cases and 342,000 deaths reported annually, with the vast majority diagnosed in low income countries. Despite high-risk Human Papillomavirus (HR HPV)-induced cervical cancer has become highly preventable through prophylactic vaccines, screening programs are critical in the control of cervical carcinogenesis in populations with limited access to vaccination and in older generations of women who have already been exposed to HR HPV infection. The surge of HPV molecular tests has provided a more sensitive and accurate diagnostic alternative to cytology screening.

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Introduction: Patients suffering from advanced heart failure may undergo left ventricular assist device (LVAD) placement as a bridge to cardiac transplantation. However, those with a BMI above 35 kg/m are generally not considered eligible for transplant due to their elevated cardiac risk. We review our experience with bariatric surgery in this high-risk population to assess its safety and efficacy in reducing BMI to permit cardiac transplantation.

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Gumboro illness is caused by the highly contagious immunosuppressive infectious bursal disease virus (IBDV), which affects the poultry industry globally. We have previously shown that IBDV hijacks the endocytic pathway to construct viral replication complexes on endosomes linked to the Golgi complex (GC). Then, analyzing crucial proteins involved in the secretory pathway, we showed the essential requirement of Rab1b, the Rab1b downstream effector Golgi-specific BFA resistance factor 1 (GBF1), and its substrate, the small GTPase ADP-ribosylation factor 1 (ARF1), for IBDV replication.

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We present a new methodology to quantify the variability of resistive switching memories. Instead of statistically analyzing few data points extracted from current versus voltage (-) plots, such as switching voltages or state resistances, we take into account the whole - curve measured in each RS cycle. This means going from a one-dimensional data set to a two-dimensional data set, in which every point of each - curve measured is included in the variability calculation.

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A methodology to estimate the device temperature in resistive random access memories (RRAMs) is presented. Unipolar devices, which are known to be highly influenced by thermal effects in their resistive switching operation, are employed to develop the technique. A 3D RRAM simulator is used to fit experimental data and obtain the maximum and average temperatures of the conductive filaments (CFs) that are responsible for the switching behavior.

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Exploiting the excellent electronic properties of two-dimensional (2D) materials to fabricate advanced electronic circuits is a major goal for the semiconductor industry. However, most studies in this field have been limited to the fabrication and characterization of isolated large (more than 1 µm) devices on unfunctional SiO-Si substrates. Some studies have integrated monolayer graphene on silicon microchips as a large-area (more than 500 µm) interconnection and as a channel of large transistors (roughly 16.

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Introduction: The SynCardia total artificial heart (TAH) is the only device approved for biventricular support. Continuous flow ventricular assist devices (VAD) in a biventricular configuration (BiVAD) have been used with variable results. The purpose of this report was to examine differences in patient characteristics and outcomes between two HeartMate-3 (HM-3) VADs in comparison with TAH support.

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Background: Mucinous cystic neoplasms of the pancreas are uncommon tumors that have the potential of becoming cancer. There is no consensus regarding the high-risk features of these tumors. Our study aimed to identify the preoperative demographic, clinical, or radiologic factors that can predict the presence of high-grade dysplasia or invasive carcinoma in mucinous cystic neoplasms of the pancreas.

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The development of the internet-of-things requires cheap, light, small and reliable true random number generator (TRNG) circuits to encrypt the data-generated by objects or humans-before transmitting them. However, all current solutions consume too much power and require a relatively large battery, hindering the integration of TRNG circuits on most objects. Here we fabricated a TRNG circuit by exploiting stable random telegraph noise (RTN) current signals produced by memristors made of two-dimensional (2D) multi-layered hexagonal boron nitride (h-BN) grown by chemical vapor deposition and coupled with inkjet-printed Ag electrodes.

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