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The proliferation of radio frequency (RF) devices in contemporary society, especially in the fields of smart homes, Internet of Things (IoT) gadgets, and smartphones, underscores the urgent need for robust identification methods to strengthen cybersecurity. This paper delves into the realms of RF fingerprint (RFF) based on applying the Jensen-Shannon divergence (JSD) to the statistical distribution of noise in RF signals to identify Bluetooth devices. Thus, through a detailed case study, Bluetooth RF noise taken at 5 Gsps from different devices is explored. A noise model is considered to extract a unique, universal, permanent, permanent, collectable, and robust statistical RFF that identifies each Bluetooth device. Then, the different JSD noise signals provided by Bluetooth devices are contrasted with the statistical RFF of all devices and a membership resolution is declared. The study shows that this way of identifying Bluetooth devices based on RFF allows one to discern between devices of the same make and model, achieving 99.5% identification effectiveness. By leveraging statistical RFFs extracted from noise in RF signals emitted by devices, this research not only contributes to the advancement of the field of implicit device authentication systems based on wireless communication but also provides valuable insights into the practical implementation of RF identification techniques, which could be useful in forensic processes.

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Reciprocating compressors and centrifugal pumps are rotating machines used in industry, where fault detection is crucial for avoiding unnecessary and costly downtime. A novel method for fault classification in reciprocating compressors and multi-stage centrifugal pumps is proposed. In the feature extraction stage, raw vibration signals are processed using multi-fractal detrended fluctuation analysis (MFDFA) to extract features indicative of different types of faults. Such MFDFA features enable the training of machine learning models for classifying faults. Several classical machine learning models and a deep learning model corresponding to the convolutional neural network (CNN) are compared with respect to their classification accuracy. The cross-validation results show that all models are highly accurate for classifying the 13 types of faults in the centrifugal pump, the 17 valve faults, and the 13 multi-faults in the reciprocating compressor. The random forest subspace discriminant (RFSD) and the CNN model achieved the best results using MFDFA features calculated with quadratic approximations. The proposed method is a promising approach for fault classification in reciprocating compressors and multi-stage centrifugal pumps.

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ABSTRACT Objective: To compare the hypotensive effect of SLT vs the use of latanoprost in the initial management of patients with suspected glaucoma and diagnosis of glaucoma. To evaluate the patients' quality of life using the Glaucoma Quality of Life questionnaire. Methods: Randomized controlled clinical trial conducted in the city of Cartagena, Colombia, between October 2021 to June 2023. Assignment to the SLT or latanoprost group with follow-up at days 7, 30, 90, 180, and 365 in patients diagnosed with suspected glaucoma, mild and moderate glaucoma. Results: 31 patients (60 eyes), of which 17 were men. Group SLT were 31 eyes and the latanoprost group included 29 eyes. The mean baseline IOP of the SLT group was 18.9mmHg and in the latanoprost group, it was 19.6mmHg. The mean IOP at the end of the follow-up group SLT was 13.9mmHg and for latanoprost 14.5mmHg. The IOP reduction percentage at one year of follow-up in the SLT group was 23.4% and that of the latanoprost group was 23.6% Conclusions: Selective laser trabeculoplasty with Nd-YAG laser is as effective as the use of prostaglandin analogues as initial treatment in the early stages of glaucoma. Regarding the quality of life scale, although there were no statistically significant differences in both groups, the SLT showed an increase in the difficulty perceived by the patient for activities that involve peripheral vision, which is the most affected in patients with glaucoma.

RESUMO Objetivo: Comparar o efeito hipotensor da trabeculoplastia seletiva a laser versus o uso de latanoprosta no tratamento inicial de pacientes com suspeita de glaucoma e diagnóstico de glaucoma; avaliar a qualidade de vida dos pacientes por meio do Glaucoma Quality of Life Survey. Métodos: Ensaio clínico randomizado controlado realizado na cidade de Cartagena, Colômbia, entre outubro de 2021 e junho de 2023. Atribuição ao grupo trabeculoplastia seletiva a laser ou latanoprosta com acompanhamento nos dias 7, 30, 90, 180 e 365 em pacientes diagnosticados com suspeita de glaucoma, glaucoma leve e moderado. Resultados: Foram incluídos 31 pacientes (60 olhos), sendo 17 homens. No Grupo Trabeculoplastia Seletiva a Laser, foram 31 olhos, e, no Grupo Latanoprosta, 29 olhos. A pressão intraocular basal média do Grupo Trabeculoplastia Seletiva a Laser foi de 18,9mmHg e, no Grupo Latanoprosta, foi de 19,6mmHg. A pressão intraocular média no fim do grupo de acompanhamento trabeculoplastia seletiva a laser foi de 13,9mmHg e para latanoprosta de 14,5mmHg. A percentagem de redução da pressão intraocular em 1 ano de acompanhamento no Grupo Trabeculoplastia Seletiva a Laser foi de 23,4% e a do Grupo Latanoprosta foi de 23,6%. Conclusões: A trabeculoplastia seletiva a laser com Nd-YAG é tão eficaz quanto o uso de análogos de prostaglandinas como tratamento nas fases iniciais do glaucoma. Em relação à escala de qualidade de vida, embora não tenha havido diferenças estatisticamente significativas em ambos os grupos, a A trabeculoplastia seletiva a laser mostrou aumento na dificuldade percebida pelo paciente para atividades que envolvem a visão periférica, que é a mais afetada em pacientes com glaucoma.

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In this work, we propose a versatile, low-cost, and tunable electronic device to generate realistic electrocardiogram (ECG) waveforms, capable of simulating ECG of patients within a wide range of possibilities. A visual analysis of the clinical ECG register provides the cardiologist with vital physiological information to determine the patient's heart condition. Because of its clinical significance, there is a strong interest in algorithms and medical ECG measuring devices that acquire, preserve, and process ECG recordings with high fidelity. Bearing this in mind, the proposed electronic device is based on four different mathematical models describing macroscopic heartbeat dynamics with ordinary differential equations. Firstly, we produce full 12-lead ECG profiles by implementing a model comprising a network of heterogeneous oscillators. Then, we implement a discretized reaction-diffusion model in our electronic device to reproduce ECG waveforms from various rhythm disorders. Finally, in order to show the versatility and capabilities of our system, we include two additional models, a ring of three coupled oscillators and a model based on a quasiperiodic motion, which can reproduce a wide range of pathological conditions. With this, the proposed device can reproduce around thirty-two cardiac rhythms with the possibility of exploring different parameter values to simulate new arrhythmias with the same hardware. Our system, which is a hybrid analog-digital circuit, generates realistic ECG signals through digital-to-analog converters whose amplitudes and waveforms are controlled through an interactive and friendly graphic interface. Our ECG patient simulator arises as a promising platform for assessing the performance of electrocardiograph equipment and ECG signal processing software in clinical trials. Additionally the produced 12-lead profiles can be tested in patient monitoring systems.

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Stingless bees are the largest group of eusocial pollinators with diverse natural histories, including obligate cleptobionts (genus Lestrimelitta) that completely abandoned flower visitation to rely on other stingless bees for food and nest materials. Species of Lestrimeliita are thought to specialize upon different host species, and deception through chemical similarity has been proposed as a mechanism to explain this phenomenon. In the Yucatan Peninsula of Mexico, Scaptotrigona pectoralis is a species chemically distinct from, and not preferred as a host by, locally widespread Lestrimeliita niitkib; witnessing attacks on S. pectoralis colonies offered the opportunity to test the sensory deception hypothesis to cletoparasitism. Analysis of cuticular profiles revealed that the Lestrimelitta attacking S. pectoralis differed significantly in odour bouquet to L. niitkib and, in contrast, it resembled that of S. pectoralis. Further analyses, including morphometrics, mtDNA barcoding, and the examination of taxonomic features, confirmed the existence of two sympatric Lestrimelitta species. The results give support to the hypothesis of chemical deception as a cleptobiotic strategy in Lestrimelitta sp. This is the first evidence that sympatric cleptobionts of the same genus select hosts in accordance with species-specific cuticular profiles, with possible consequences for ecological adaptation and the evolution of these remarkable organisms and the community of stingless bee hosts.

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Multi-drug resistant (MDR) non-typhoidal Salmonella (NTS) is a public health concern globally. This study reports the phenotypic and genotypic antimicrobial resistance (AMR) profiles of NTS isolates from bovine lymph nodes (n = 48) and ground beef (n = 29). Furthermore, we compared genotypic AMR data of our isolates with those of publicly available NTS genomes from Mexico (n = 2400). The probability of finding MDR isolates was higher in ground beef than in lymph nodes:χ2 = 12.0, P = 0.0005. The most common resistant phenotypes involved tetracycline (40.3%), carbenicillin (26.0%), amoxicillin-clavulanic acid (20.8%), chloramphenicol (19.5%) and trimethoprim-sulfamethoxazole (16.9%), while more than 55% of the isolates showed decreased susceptibility to ciprofloxacin and 26% were MDR. Conversely, resistance to cephalosporins and carbapenems was infrequent (0-9%). MDR phenotypes were strongly associated with NTS serovar (χ2 = 24.5, P<0.0001), with Typhimurium accounting for 40% of MDR strains. Most of these (9/10), carried Salmonella genomic island 1, which harbors a class-1 integron with multiple AMR genes (aadA2, blaCARB-2, floR, sul1, tetG) that confer a penta-resistant phenotype. MDR phenotypes were also associated with mutations in the ramR gene (χ2 = 17.7, P<0.0001). Among public NTS isolates from Mexico, those from cattle and poultry had the highest proportion of MDR genotypes. Our results suggest that attaining significant improvements in AMR meat safety requires the identification and removal (or treatment) of product harboring MDR NTS, instead of screening for Salmonella spp. or for isolates showing resistance to individual antibiotics. In that sense, massive integration of whole genome sequencing (WGS) technologies in AMR surveillance provides the shortest path to accomplish these goals.

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The coffee berry borer (CBB) is one of the main coffee pests in the world including Colombia. This pest is difficult to manage because of its cryptic habits and the continuous availability of coffee fruits. Among the new management strategies being tested is the use of volatile compounds as insect repellents. In this work, the behavioral response of female adult CBBs to terpenes previously identified in the CBB-repellent plant species Lantana camara was evaluated. α-Terpinene, (R)-limonene, farnesene and ß-caryophyllene terpenes were tested via a Y-tube olfactometer in which ripe coffee fruits were accompanied by terpenes at concentrations between 25 and 200 ppm. Only ß-caryophyllene induced a significant and consistent CBB repellent effect at all tested doses. The protective effect of microencapsulated ß-caryophyllene was then determined under laboratory conditions by incorporating the terpene in a colloidosome-gel system at 2.8 × 105 ng/h in the middle of coffee fruits with adult CBBs. The coffee fruits in turn presented a decrease in fruit infestation. Furthermore, the protection of coffee fruits when ß-caryophyllene gels were hung in coffee trees was evaluated in the field; infestations were artificially induced by the use of raisins (CBB-infested old coffee fruits) placed on the ground. Compared with unprotected trees, the trees treated with caryophyllene gels exhibited a 33 to 45% lower degree of infestation. Taken together, the results show that ß-caryophyllene is a promising compound for an integrated pest management (IPM) program in commercial coffee plantations.

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This work reports a multilead QT interval measurement algorithm for a high-resolution digital electrocardiograph. The software enables off-line ECG processing including QRS detection as well as an accurate multilead QT interval detection algorithm using support vector machines (SVMs). Two fiducial points (Q ini and T end) are estimated using the SVM algorithm on each incoming beat. This enables segmentation of the current beat for obtaining the P, QRS, and T waves. The QT interval is estimated by updating the QT interval on each lead, considering shifting techniques with respect to a valid beat template. The validation of the QT interval measurement algorithm is attained using the Physionet PTB diagnostic ECG database showing a percent error of 2.60 ± 2.25 msec with respect to the database annotations. The usefulness of this software tool is also tested by considering the analysis of the ECG signals for a group of 60 patients acquired using our digital electrocardiograph. In this case, the validation is performed by comparing the estimated QT interval with respect to the estimation obtained using the Cardiosoft software providing a percent error of 2.49 ± 1.99 msec.

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La fístula palatina anterior es la comunicación anormal entre la cavidad oral y la nariz que se presenta después del cierre quirúrgico de la fisura palatina, ésta ocurre con más frecuencia en defectos de paladar duro. El colgajo de lengua está indicado para la reconstrucción de grandes fístulas palatinas y con excesivas cicatrices palatinas luego de varios procedimientos insatisfactorios. El colgajo ofrece varias ventajas ya que presenta abundante tejido, excelente irrigación y es de fácil rotación. El resultado fue satisfactorio.

The anterior palatal fistula is the abnormal communication between the oral cavity and nose that occurs after surgical closure of cleft palate, this occurs more frequently in hard palate defects. Tongue flap is indicated for the reconstruction of large fistulas and excessive palatal scars after several unsatisfactory procedures. The flap offers several advantages since it presents abundant tissue, excellent irrigation and easy rotation. The result was satisfactory.

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Resumen - El presente trabajo reporta el desarrollo de una tarjeta de adquisición de datos para uso biomédico. El proyecto consta de una etapa de hardware y una de software. La etapa de hardware permite la digitalización multicanal de 8 señales, con una velocidad de adquisición de 2000 muestras por segundo (mps) en cada canal y 12 bits de resolución por muestra. El software de aplicación se diseñó con la finalidad de visualizar en tiempo real y almacenar en el computador las señales adquiridas. Este proyecto se realizó buscando desarrollar tecnología propia, que permita la adquisición simultánea de los doce canales del electrocardiograma (ECG) superficial estándar, con características de alta resolución (ECGAR). La tarjeta de adquisición de datos reportada se diseña como parte de un proyecto, que tiene como propósito obtener la representación digital de la señal ECG multicanal, con las características adecuadas para aplicar técnicas de análisis especializadas que permitan estudiar enfermedades cardiovasculares de metabolismo retardado, como el mal de Chagas. En las pruebas realizadas se constató que el sistema presenta errores inferiores al 0,15 % en las mediciones de amplitud y no presenta perdida de información en la comunicación del hardware con la computadora. También se constató que la representación gráfica de las señales adquiridas es de muy buena calidad para su implementación por médicos especialistas.

Abstract - This paper reports the development of a data acquisition card for biomedical use. The project involves development of hardware and software. The hardware enables acquisition of 10 analog signals, at a rate of 2000 samples per channel per second (mps) and 12-bit resolution per sample. The application software was designed for visualizing and storing, in real time, the acquired signals. This project was performed aiming at developing proprietary technology, for simultaneous acquisition of 12 leads of the standard electrocardiogram (ECG) including high resolution (ECGAR) features. The acquisition card was designed as part of a larger project aiming at developing a high resolution electrocardiograph, incorporating advanced digital processing techniques for research about cardiovascular diseases such as the Chagas disease. The tests performed for this acquisition card show amplitude errors lower than 0.15 % and no loss of information during the communication with the computer. It was also found that the graphical representation of the acquired signals is of high quality for interpretation by cardiologists.

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