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The BC501A sensor is a liquid scintillator frequently used in nuclear physics for detecting fast neutrons. This paper describes a hardware implementation of digital pulse shape analysis (DPSA) for real-time analysis. DPSA is an algorithm that extracts the physically relevant parameters from the detected BC501A signals. The hardware solution is implemented in a MicroTCA system that provides the physical, mechanical, electrical, and cooling support for an AMC board (NAMC-ZYNQ-FMC) with a Xilinx ZYNQ Ultrascale-MP SoC. The Xilinx FPGA programmable logic implements a JESD204B interface to high-speed ADCs. The physical and datalink JESD204B layers are implemented using hardware description language (HDL), while the Xilinx high-level synthesis language (HLS) is used for the transport and application layers. The DPSA algorithm is a JESD204B application layer that includes a FIR filter and a constant fraction discriminator (CFD) function, a baseline calculation function, a peak detection function, and an energy calculation function. This architecture achieves an analysis mean time of less than 100 µs per signal with an FPGA resource utilization of about 50% of its most used resources. This paper presents a high-performance DPSA embedded system that interfaces with a 1 GS/s ADC and performs accurate calculations with relatively low latency.
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The development and implementation of artificial intelligence (AI), particularly deep learning (DL) models, has generated significant interest across various fields of gastroenterology. While research in luminal endoscopy has seen rapid translation to clinical practice with approved AI devices, its potential extends far beyond, offering promising benefits for biliopancreatic endoscopy like optical characterization of strictures during cholangioscopy or detection and classification of pancreatic lesions during diagnostic endoscopic ultrasound (EUS). This narrative review provides an up-to-date of the latest literature and available studies in this field. Serving as a comprehensive guide to the current landscape of AI in biliopancreatic endoscopy, emphasizing technological advancements, main applications, ethical considerations, and future directions for research and clinical implementation.
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Acute pancreatitis is associated with significant morbidity and mortality. It can develop complications such as fluid collections and necrosis. Infection of necrosis occurs in about 20-40% of patients with severe acute pancreatitis, and is associated with organ failure and worse prognosis. In the past years, the treatment of pancreatic collections has shifted from open surgery to minimally invasive techniques, such as endoscopic ultrasound guided drainage. These guidelines from a selection of experts among the Endoscopic Ultrasound Group from the Spanish Society of Gastrointestinal Endoscopy (GSEED-USE) have the purpose to provide advice on the management of pancreatic collections based on a thorough review of the available scientific evidence. It also reflects the experience and clinical practice of the authors, who are advanced endoscopists or clinical pancreatologists with extensive experience in managing patients with acute pancreatitis.
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Nondestructive evaluation of carbon fiber reinforced material structures has received special attention in the last decades. Usage of Ultrasonic Guided Waves (UGW), particularly Lamb waves, has become one of the most popular techniques for damage location, due to their sensitivity to defects, large range of inspection, and good propagation in several material types. However, extracting meaningful physical features from the response signals is challenging due to several factors, such as the multimodal nature of UGW, boundary conditions and the geometric shape of the structure, possible material anisotropies, and their environmental dependency. Neural networks (NN) are becoming a practical and accurate approach to analyzing the acquired data using data-driven methods. In this paper, a Convolutional-Neural-Network (CNN) is proposed to predict the distance-to-damage values from the signals corresponding to a transmitter-receiver path of transducers. The NN input is a 2D image (time-frequency) obtained as the Wavelet transform of the acquired experimental signals. The distances obtained with the NN are the input of a novel damage location algorithm which outputs a bidimensional image of the structure's surface showing the estimated damage locations with a deviation of the actual position lower than 15 mm.
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Redes Neurais de Computação , Análise de Ondaletas , AlgoritmosRESUMO
BACKGROUND AND AIMS: EMR is increasingly used for resection of sporadic, nonampullary duodenal adenomas (SNDAs), but there are no guidelines for the management of these lesions. The aims of this study were to evaluate the safety and efficacy of EMR exclusively for SNDAs and to determine the factors predictive of outcomes. METHODS: We performed a retrospective review of patients with SNDAs referred for endoscopic therapy from 2006 to 2013. The outcomes studied were successful endoscopic resection, major adverse events, early and late recurrences, and clinical remission. RESULTS: Sixty-eight patients with SNDAs were included and 51 (75%) underwent EMR. The mean adenoma size was 22.0 ± 8.9 mm. Successful resection was achieved in 49 of 51 patients (96.1%), and major adverse events were noted in 8 of 51 patients (15.7%). Early and late recurrences were noted in 25.6% and 5.2% of patients, respectively, and were treated endoscopically. Clinical remission was achieved in 89.7% of patients after a median follow-up of 15 months. Presence of villous histology was associated with increased recurrence (P = .019), but no association of recurrence was noted with other endoscopic features or resection technique. Large adenoma size (P = .0057) and need for intraprocedural hemostasis (P = .006) were associated with increased adverse events, but no association of adverse events was noted with location or resection technique. CONCLUSIONS: Large duodenal adenomas can be effectively managed with EMR at a referral center with experienced endoscopists. However, EMR has a significant recurrence rate, especially early recurrence, and the risk of adverse events is not negligible. Endoscopic therapy is successful in managing recurrent adenomas.
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Adenoma/patologia , Adenoma/cirurgia , Neoplasias Duodenais/patologia , Neoplasias Duodenais/cirurgia , Ressecção Endoscópica de Mucosa , Recidiva Local de Neoplasia/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Perda Sanguínea Cirúrgica , Ressecção Endoscópica de Mucosa/efeitos adversos , Endoscopia Gastrointestinal , Feminino , Hemostase Endoscópica , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Carga TumoralRESUMO
BACKGROUND & AIMS: Barrett's esophagus (BE) with high-grade dysplasia (HGD) or intramucosal carcinoma (IMC) is treated by complete eradication of areas of BE by endoscopic mucosal resection (EMR). By using this approach, histologic analysis also can be performed. We investigated the effectiveness, safety, and durability of this approach, as well as its use in diagnosis after a single referral. METHODS: We collected data from 107 patients who were referred to the Center for Endoscopic Research and Therapeutics at the University of Chicago for BE (mean length, 3.6 cm) with suspected HGD or IMC, from August 2003 through December 2012. All patients underwent EMR and were followed up through January 2014 (mean follow-up time, 40.6 mo). The primary outcome was treatment efficacy (complete eradication of BE and associated neoplasia); secondary outcomes included safety, durability, and accuracy of diagnosis. RESULTS: BE was eradicated completely by EMR in 80.4% (86 of 107) of patients based on intention-to-treat analysis, and in 98.8% (79 of 80) of patients based on per-protocol analysis. The diagnosis was changed for 25% of patients after EMR, including 4 cases that initially were diagnosed as HGD by biopsy analysis and subsequently were found to have evidence of submucosal invasion when EMR specimens were assessed. Strictures and symptomatic dysphagia developed in 41.1% and 37.3% of patients, respectively, with an average of 2.3 dilations required. Perforations occurred in 2 patients after EMR and in 1 patient after dilation. HGD and IMC recurred in 1 patient each; both were treated successfully with EMR. Based on pathology analysis of the most recently collected specimens, 71.6% of patients (53 of 74) were in complete remission from intestinal metaplasia and 100% were in complete remission from HGD (74 of 74) or cancer (74 of 74). CONCLUSIONS: For patients with BE with HGD or neoplasia, complete EMR is an effective and durable treatment and is a relatively safe technique. Specimens collected by EMR also can be analyzed histologically to aid in diagnosis. The common complication of EMR is esophageal stricture, which can be addressed with endoscopic dilation.
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Esôfago de Barrett/complicações , Carcinoma/cirurgia , Endoscopia/métodos , Neoplasias Esofágicas/cirurgia , Idoso , Carcinoma/diagnóstico , Chicago , Endoscopia/efeitos adversos , Endoscopia/estatística & dados numéricos , Neoplasias Esofágicas/diagnóstico , Feminino , Humanos , Masculino , Resultado do TratamentoRESUMO
Barrett's esophagus is an area of great interest in Gastroenterology, with an increasing number of research studies being published in recent years and decades. Due to the fast growing evidence regarding this disease, it has become extremely difficult to keep updated on this subject. The present review article aims to summarize and update what is known regarding diagnosis and therapy in Barrett's esophagus. A critical and detailed review is made and the role of surveillance for this condition, techniques available for diagnosis (standard white light endoscopy, virtual chromoendoscopy, magnification...) and treatment (mucosectomy, ablation...) are presented. New and emerging technologies are described in detail and existing evidence is presented.
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Esôfago de Barrett/diagnóstico , Endoscopia Gastrointestinal/métodos , Esôfago de Barrett/terapia , Endoscopia Gastrointestinal/efeitos adversos , HumanosRESUMO
BACKGROUND AND OBJECTIVES: Early treatment is associated with better long-term outcomes in patients with a first demyelinating event and early multiple sclerosis (MS). However, magnetic resonance (MR) findings are not usually integrated to construct propensity scores (PSs) when evaluating outcomes. We assessed the association of receiving very early treatment with the risk of long-term disability including an MR score (MRS) in patients with a first demyelinating event. METHODS: We included 580 patients with a first demyelinating event prospectively collected between 1994 and 2021, who received at least 1 disease-modifying drug (DMD). Patients were classified into tertiles according to the cohort's distribution of the time from the first demyelinating event to the first DMD: first tertile (FT) or very early treatment (6 months; n = 194), second tertile (6.1-16 months, n = 192), and third tertile (TT) (16.1 months, n = 194). A 5-point MRS was built according to the sum of the following indicators: ≥9 brain lesions (1 point); ≥1 infratentorial lesion (1 point); ≥1 spinal cord (SC) lesion (1 point); ≥1 contrast-enhancing (CE) brain lesion (1 point); and ≥1 CE SC lesion (1 point). PS based on covariates and the MRS was computed for each of the outcomes. Inverse PS-weighted Cox and linear regression models assessed the risk of different outcomes between tertile groups. Finally, to confirm the role of MR in treatment decision, we studied the time elapsed from the first demyelinating event to treatment initiation according to the MRS in all patients with radiologic available information, renamed as raw-MRS. RESULTS: Very early treatment decreased the risk of reaching Expanded Disability Status Scale 3.0 (hazard ratio [HR] 0.55, 95% CI 0.32-0.97), secondary progressive MS (HR 0.40, 95% CI 0.19-0.85), and sustained disease progression at 12 months after treatment initiation (HR 0.50, 95% CI 0.29-0.84), when compared with patients from the TT group. Patients from the FT group had a lower disability progression rate (ß estimate -0.009, 95% CI -0.016 to -0.002) and a lower severe disability measured by the Patient-Determined Disease Step (ß estimate -0.52, 95% CI -0.91 to -0.13) than the TT group. Finally, there was a 62.4% reduction in the median time between the first demyelinating event and the first-ever treatment initiation from patients displaying a raw-MRS 1 to patients with a raw-MRS 5. DISCUSSION: Using PS models with and without MRS, we showed that treatment initiation at very early stages is associated with a reduction in the risk of long-term disability accrual in patients with a first demyelinating event. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that earlier treatment of patients with MS presenting with a first demyelinating event is associated with improved clinical outcomes.
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Esclerose Múltipla Crônica Progressiva , Esclerose Múltipla , Humanos , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/patologia , Imageamento por Ressonância Magnética , Encéfalo/patologiaRESUMO
Magnetorheological elastomers, MREs, based on elastic organic matrices displaying anisotropic magnetoresistance and piezoresistivity at room temperature were prepared and characterized. These materials are dispersions of superparamagnetic magnetite forming cores of aggregated nanoparticles inside silver microparticles that are dispersed in an elastomeric polymer (poly(dimethylsiloxane), PDMS), curing the polymer in the presence of a uniform magnetic field. In this way, the elastic material becomes structured as the application of the field induces the formation of filaments of silver-covered inorganic material agglomerates (needles) aligned in the direction of the field (parallel to the field). Because the magnetic particles are covered with silver, the MREs are not only magnetic but also electrical conductors. The structuration induces elastic, magnetic, and electrical anisotropic properties. For example, with a low concentration of particles in the elastic matrix (5% w/w) it is possible to obtain resistances of a few ohms when measured parallel to the needles or several megaohms in the perpendicular direction. Magnetite nanoparticles (Fe(3)O(4) NP) were synthesized by the coprecipitation method, and then agglomerations of these NPs were covered with Ag. The average size of the obtained magnetite NPs was about 13 nm, and the magnetite-silver particles, referred to as Fe(3)O(4)@Ag, form micrometric aggregates (1.3 µm). Nanoparticles, microparticles, and the MREs were characterized by XRD, TEM, SEM, EDS, diffuse reflectance, voltammetry, VSM, and SQUID. At room temperature, the synthesized magnetite and Fe(3)O(4)@Ag particles are in a superparamagnetic state (T(B) = 205 and 179 K at 0.01 T as determined by SQUID). The elastic properties and Young's modulus of the MREs were measured as a function of the orientation using a texture analysis device. The magnetic anisotropy in the MRE composite was investigated by FMR. The electrical conductivity of the MRE (σ) increases exponentially when a pressure, P, is applied, and the magnitude of the change strongly depends on what direction P is exerted (anisotropic piezoresistivity). In addition, at a fixed pressure, σ increases exponentially in the presence of an external magnetic field (H) only when the field H is applied in the collinear direction with respect to the electrical flux, J. Excellent fits of the experimental data σ versus H and P were achieved using a model that considers the intergrain electron transport where an H-dependent barrier was considered in addition to the intrinsic intergrain resistance in a percolation process. The H-dependent barrier decreases with the applied field, which is attributed to the increasing match of spin-polarization in the silver covers between grains. The effect is anisotropic (i.e., the sensitivity of the magnetoresistive effect is dependent on the relative orientation between H and the current flow J). In the case of Fe(3)O(4)@ Ag, when H and J are parallel to the needles in the PDMS matrix, we obtain changes in σ up to 50% for fields of 400 mT and with resistances on the order of 1-10 Ω. Magnetoresistive and magnetoelastic properties make these materials very interesting for applications in flexible electronics, electronic skins, anisotropic pressure, and magnetic field sensors.
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The acid-base speciation of coordinated azanone (HNO) remains a highly relevant topic in bioinorganic chemistry. Ruthenium nitroxyl complexes with sufficient robustness towards ligand loss have gained significance as operating platforms to delve into such studies. In this work, we revisit an octahedral {RuNO}6 complex containing the cyclam-based pentadentate ligand Lpy = 1-(pyridine-2-ylmethyl)-1,4,8,11-tetraazacyclotetradecane and explore the thermodynamic and spectroscopic aspects of its reduced states in aqueous media. Upon in situ electro-generation of the bound HNO moiety, we have undertaken different strategies to determine both its acidity and electrochemical properties. This robust HNO complex does not undergo deprotonation in a wide pH range. We have found pKa ([Ru(Lpy)(HNO)]2+) = 13.0 ± 0.1 and . There are indications that pKa (HNO) values in several ruthenium-based species correlate with the redox potential associated with the {RuNO}6,7 and {RuNO}7,8 couples. The present pKa extends the range of acidity of bound HNO to more than five pH units, confirming a remarkable sensitivity to the nature of the coordination sphere. This result lays new foundations to continue rational ligand design that may contribute to a better understanding of the different biological roles of both HNO and NO- by investigating key chemical aspects of model complexes.
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Two methods, the first physical and the other chemical, were investigated to modify the surface roughness of polydimethylsiloxane (PDMS) films. The physical method consisted of dispersing multi-walled carbon nanotubes (MWCNTs) and magnetic cobalt ferrites (CoFe2O4) prior to thermal cross-linking, and curing the composite system in the presence of a uniform magnetic field H. The chemical method was based on exposing the films to bromine vapours and then UV-irradiating. The characterizing techniques included scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), Fourier transform infrared (FTIR) spectroscopy, optical microscopy, atomic force microscopy (AFM) and magnetic force microscopy (MFM). The surface roughness was quantitatively analyzed by AFM. In the physical method, the random dispersion of MWCNTs (1% w/w) and magnetic nanoparticles (2% w/w) generated a roughness increase of about 200% (with respect to PDMS films without any treatment), but that change was 400% for films cured in the presence of H perpendicular to the surface. SEM, AFM and MFM showed that the magnetic particles always remained attached to the carbon nanotubes, and the effect on the roughness was interpreted as being due to a rupture of dispersion randomness and a possible induction of structuring in the direction of H. In the chemical method, the increase in roughness was even greater (1000%). Wells were generated with surface areas that were close to 100 µm² and depths of up to 500 nm. The observations of AFM images and FTIR spectra were in agreement with the hypothesis of etching by Br radicals generated by UV on the polymer chains. Both methods induced important changes in the surface roughness (the chemical method generated the greatest changes due to the formation of surface wells), which are of great importance in superficial technological processes.
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OBJECTIVES: To reduce pancreatic cancer mortality, a paradigm shift in cancer screening is needed. Our group pioneered the use of low-coherence enhanced backscattering (LEBS) spectroscopy to predict the presence of pancreatic cancer by interrogating the duodenal mucosa. A previous ex vivo study (n = 203) demonstrated excellent diagnostic potential: sensitivity, 95%; specificity, 71%; and accuracy, 85%. The objective of the current case-control study was to evaluate this approach in vivo. METHODS: We developed a novel endoscope-compatible fiber-optic probe to measure LEBS in the periampullary duodenum of 41 patients undergoing upper endoscopy. This approach enables minimally invasive detection of the ultrastructural consequences of pancreatic field carcinogenesis. RESULTS: The LEBS parameters and optical properties were significantly altered in patients harboring adenocarcinomas (including early-stage) throughout the pancreas relative to healthy controls. Test performance characteristics were excellent with sensitivity = 78%, specificity = 85%, and accuracy = 81%. Moreover, the LEBS prediction rule was not confounded by patients' demographics. CONCLUSION: We demonstrate the feasibility of in vivo measurement of histologically normal duodenal mucosa to predict the presence of adenocarcinoma throughout the pancreas. This represents the next step in establishing duodenal LEBS analysis as a prescreening technique that identifies clinically asymptomatic patients who are at elevated risk of PC.
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Adenocarcinoma/ultraestrutura , Duodenoscopia/métodos , Duodeno/ultraestrutura , Tecnologia de Fibra Óptica/métodos , Mucosa Intestinal/ultraestrutura , Neoplasias Pancreáticas/ultraestrutura , Adulto , Idoso , Estudos de Casos e Controles , Duodenoscópios , Duodenoscopia/instrumentação , Desenho de Equipamento , Estudos de Viabilidade , Feminino , Tecnologia de Fibra Óptica/instrumentação , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Medição de Risco , Fatores de Risco , Análise EspectralRESUMO
Piezoelectric sensors and actuators are the bridge between electronic and mechanical systems in structures. This type of sensor is a key element in the integrity monitoring of aeronautic structures, bridges, pressure vessels, wind turbine blades, and gas pipelines. In this paper, an all-in-one system for Structural Health Monitoring (SHM) based on ultrasonic waves is presented, called Phased Array Monitoring for Enhanced Life Assessment. This integrated instrument is able to generate excitation signals that are sent through piezoelectric actuators, acquire the received signals in the piezoelectric sensors, and carry out signal processing to check the health of structures. To accomplish this task, the instrument uses a piezoelectric phased-array transducer that performs the actuation and sensing of the signals. The flexibility and strength of the instrument allow the user to develop and implement a substantial part of the SHM technique using Lamb waves. The entire system is controlled using configuration software and has been validated through functional, electrical loading, mechanical loading, and thermal loading resistance tests.
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Monitorização Fisiológica/instrumentação , Ultrassom , Fenômenos Mecânicos , Temperatura , TransdutoresRESUMO
OBJECTIVES: Atypical lymphatic spread of germ cell tumors to inguinal lymph nodes has been reported mostly related to prior surgical involvement of the inguinoscrotal region, as in orchiopexy. METHODS: A patient with cryptorchidism and failed orchiopexy in his childhood was diagnosed with a testicular neoplasm. Inguinal orchiectomy was performed. RESULTS: Pathological analysis showed classical seminoma spreading into a subcutaneous adjacent lymph node. Further metastatic disease was not found. Patient was treated with adjuvant chemotherapy. CONCLUSIONS: We emphasize the need for accurate staging and a multidisciplinary approach when dealing with onco-urological patients presenting with atypical disease.
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Criptorquidismo/complicações , Seminoma/complicações , Seminoma/secundário , Neoplasias Testiculares/complicações , Neoplasias Testiculares/patologia , Adulto , Humanos , Metástase Linfática , MasculinoRESUMO
OBJECTIVES: Bladder leiomyoma is an uncommon mesenchymal benign tumor. It is generally asymptomatic and incidentally detected. METHODS: We report a new case managed with transurethral resection without evidence of relapse. A bibliographic search was performed to evaluate the diagnostic techniques, clinical features and treatment options of this rare disease. CONCLUSIONS: Bladder leiomyoma is a benign mesenchymal tumor originating from smooth muscle. Biopsy and histological study are required for definitive diagnosis. Surgery is the treatment of choice, and it has an excellent prognosis if resection is complete.