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Introducción: Los aneurismas de la arteria cerebral media son responsables de forma habitual de sangrados intracraneales y constituyen una localización frecuente de aneurismas. Su estrecha relación arterial y venosa en la cisterna de Silvio se acompaña de una elevada complejidad. El grapado quirúrgico presenta una elevada efectividad. Objetivo: Describir los resultados quirúrgicos de los aneurismas de la arteria cerebral media operados mediante presillamiento microquirúrgico. Método: Se realizó un estudio descriptivo, prospectivo que incluyó a 50 pacientes del Hospital Hermanos Ameijeiras operados por aneurisma cerebrales de la arteria cerebral media mediante presillamiento microquirúrgico. Se realizó una craneotomía pterional, minipterional y el grapado del aneurisma. Las variables estudiadas fueron: Clínicas, del aneurisma cerebral y posoperatorias con mayor importancia relacionada con las complicaciones y la escala de coma de Glasgow para resultados. Para el análisis de los datos se utilizaron frecuencias absolutas y relativas como medidas resumen. Resultados: Existió predominio de aneurismas no rotos (66,0 %) de tamaño grande (42,0 %) y localizados en la la bifurcación de la arteria cerebral media (94,0 %). Se empleó la craneotomía minipterional en el 74,0 %. En relación con las principales complicaciones, se reporta vasoespasmo (8,0 %), hidrocefalia (6,0 %) e infarto cerebral (4,0 %). Según la escala de coma de Glasgow para resultados, existió mayor presencia del grado 5 (78,0 %). Conclusiones: El presillamiento microquirúrgico en pacientes con aneurismas de la arteria cerebral media se acompaña de presillamiento total y escasas complicaciones posoperatorias.

Crouch gait, also referred to as flexed knee gait, is an abnormal walking pattern, characterized by an excessive flexion of the knee, and sometimes also with anomalous flexion in the hip and/or the ankle, during the stance phase of gait. Due to the fact that the amount of clinical data related to crouch gait are scarce, it is difficult to find studies addressing this problem from a data-based perspective. Consequently, in this paper we propose a gait recognition strategy using synthetic data that have been obtained using a polynomial based-generator. Furthermore, though this study, we consider datasets that correspond to different levels of crouch gait severity. The classification of the elements of the datasets into the different levels of abnormality is achieved by using different algorithms like k-nearest neighbors (KNN) and Naive Bayes (NB), among others. On the other hand, to evaluate the classification performance we consider different metrics, including accuracy (Acc) and F measure (FM). The obtained results show that the proposed strategy is able to recognize crouch gait with an accuracy of more than 92%. Thus, it is our belief that this recognition strategy may be useful during the diagnosis phase of crouch gait disease. Finally, the crouch gait recognition approach introduced here may be extended to identify other gait abnormalities.

Introducción: La derivación ventrículo peritoneal en neurocirugía constituye uno de los procedimientos más empleados para el tratamiento de la hidrocefalia. En las evidencias científicas se reportan múltiples métodos de guía transoperatoria para la colocación del catéter en el extremo craneal. Sin embargo, existe una elevada tasa de disfunción del sistema derivativo. La asistencia endoscópica en la derivación ventrículo peritoneal representa una herramienta con excelentes resultados. Objetivo: Describir los resultados quirúrgicos de la derivación ventrículo peritoneal con asistencia endoscópica. Método: Se realizó un estudio descriptivo, longitudinal y retrospectivo, que incluyó a 70 pacientes en el Hospital "Hermanos Ameijeiras" operados por hidrocefalia, a los cuales se les realizó una derivación ventrículo peritoneal con asistencia endoscópica, con sus diferentes variables: Sociodemográficas, clínicas, posquirúrgicas y complicaciones relacionadas con el procedimiento. Para el análisis de los datos se utilizaron frecuencias absolutas y relativas como medidas resumen. Resultados: La distancia promedio del catéter intracraneal fue de 10,5 cm. Existió un 97,1 % de posicionamiento óptimo del catéter intracraneal. Se reportó mejoría del estado neurológico en el 97,1 % de los pacientes. El 95,7 % del índice de Evans posoperatorio fue < 0,30. Las principales complicaciones relacionadas al procedimiento fueron: 2 pacientes con hematoma intracraneal, disfunción y revisión del sistema (2,9 %) respectivamente. Conclusiones: La derivación ventrículo peritoneal, con asistencia endoscópica para la hidrocefalia, constituye un método seguro y eficaz con disminución significativa en las complicaciones posoperatorias, en especial en la disfunción del sistema derivativo.

This work presents a new global optimization algorithm of functions inspired by the dynamic behavior of reversible cellular automata, denominated Reversible Elementary Cellular Automata Algorithm (RECAA). This algorithm adapts the reversible evolution rules in elementary cellular automata (in one dimension and only with two states) to work with vectors of real values to realize optimization tasks. The originality of RECAA lies in adapting the dynamic of the reversible elementary cellular automata to perform exploration and exploitation actions in the optimization process. This work shows that diversity in cellular automata behaviors (in this case, reversibility) is useful to define new metaheuristics to solve optimization problems. The algorithm is compared with 15 recently published metaheuristics that recognized for their good performance, using 50 test functions in 30, 500, and with a fixed number of dimensions, and the CEC 2022 benchmark suit. Additionally, it is shown that RECAA has been applied in 3 engineering problems. In all the experiments, RECAA obtained satisfactory results. RECAA was implemented in MATLAB, and its source code can be consulted in GitHub. https://github.com/juanseck/RECAA

Land Surface Temperature (LST) is a key variable used across various applications, including irrigation monitoring, vegetation health assessment and urban heat island studies. While satellites offer moderate-resolution LST data, unmanned aerial vehicles (UAVs) provide high-resolution thermal infrared measurements. However, the continuous and rapid variation in LST makes the production of orthomosaics from UAV-based image collections challenging. Understanding the environmental and meteorological factors that amplify this variation is necessary to select the most suitable conditions for collecting UAV-based thermal data. Here, we capture variations in LST while hovering for 15–20 min over diverse surfaces, covering sand, water, grass, and an olive tree orchard. The impact of different flying heights and times of the day was examined, with all collected thermal data evaluated against calibrated field-based Apogee SI-111 sensors. The evaluation showed a significant error in UAV-based data associated with wind speed, which increased the bias from −1.02 to 3.86 °C for 0.8 to 8.5 m/s winds, respectively. Different surfaces, albeit under varying ambient conditions, showed temperature variations ranging from 1.4 to 6 °C during the flights. The temperature variations observed while hovering were linked to solar radiation, specifically radiation fluctuations occurring after sunrise and before sunset. Irrigation and atmospheric conditions (i.e., thin clouds) also contributed to observed temperature variations. This research offers valuable insights into LST variations during standard 15–20 min UAV flights under diverse environmental conditions. Understanding these factors is essential for developing correction procedures and considering data inconsistencies when processing and interpreting UAV-based thermal infrared data and derived orthomosaics.

Biodegradable materials such as WE43 magnesium are of great interest for bone tissue engineering applications. This research paper presents a novel manufacturing methodology (i.e., Joining Stacking based Laser Micro-Spot Welding (JS-LMSW)) for produce tubular WE43 Magnesium scaffolds. The proposed methodology consists of laser-cut tailored geometries joined and stacked using laser micro-spot welding to form a porous structure (scaffold). The relationship between microstructure and mechanical properties of the manufactured WE43 magnesium scaffolds is summarized in this paper. Additionally, the manufactured scaffolds were dimensionally and morphologically characterized, and the obtained results are close to the designed values (relative errors of ∼ 1.04%, 0.93%, 0.83%, and 1.53% for length, width, height, and interconnected porosity, respectively). Compressive testing was conducted on the scaffolds for axial and transversal loading conditions and, micro-hardness was evaluated in the micro spot welds. The obtained results indicated that the developed WE43 magnesium scaffold features bone-like mechanical properties. The elastic modulus range of cancellous bone is between 0.01 and 0.90 GPa compared to WE43 magnesium scaffold́s elastic modulus between 0.07 and 0.41 GPa for transversal and axial conditions, respectively. Hardness results showed values between 74 HV and 80 HV in the fusion zone and heat-affected zone, respectively. This novel methodology opens a new path for the construction of complex geometries such as scaffolds.

Crouch gait is one of the most common gait abnormalities; it is usually caused by cerebral palsy. There are few works related to the modeling of crouch gait kinematics, crouch gait analysis, and visualization in both the workspace and joint space. In this work, we present a quaternion-based method to solve the forward kinematics of the position of the lower limbs during walking. For this purpose, we propose a modified eight-DoF human skeletal model. Using this model, we present a geometric method to calculate the gait inverse kinematics. Both methods are applied for gait analysis over normal, mild, and severe crouch gaits, respectively. A metric-based comparison of workspace and joint space for the three gaits for a gait cycle is conducted. In addition, gait visualization is performed using Autodesk Maya for the three anatomical planes. The obtained results allow us to determine the capabilities of the proposed methods to assess the performance of crouch gaits, using a normal pattern as a reference. Both forward and inverse kinematic methods could ultimately be applied in rehabilitation settings for the diagnosis and treatment of diseases derived from crouch gaits or other types of gait abnormalities.

Development of techniques for music visualization is important and still open problem in analysis and creation of the quantitative profiles of single or multiple compositions, which could be used as required constraints in music generation or music classification processes. When generating creative data with no objective function, it is hard to select or to find appropriate measurable features. This paper proposes a method to normalize data in MIDI files by 12 dimensional vector descriptors extracted from tonality as well as a novel technique for dimensionality reduction and visualization of extracted music data by 3D projections is discussed. Employing a non-overlapping sliding window through the composition, the harmonic features are found in a music piece. Then a self-similarity matrix is computed using distance metrics to analyze and project the resulting 3D feature vectors. Three dimensional projection creates a quantitative profile of a composition, which correlates the tone similarities along the music piece. The dimensionality reduction is compared with well-known autoencoder. Conducted tests show that our method preserves up to 90% of original data in the projection of reduced dimension. The advantages of the proposed method consist in a novel technique that provides interactive visualization and dynamically adjusts different metrics to observe the behavior of data during music information retrieval and recognition.

A two-dimensional Cellular Automata (CA) – Finite Element (FE) (CA-FE) coupled model has been developed to predict the microstructures formed during the laser melting of a powdered AA-2024 feedstock using the Additive Manufacturing (AM) process Selective Laser Melting (SLM). The presented CA model is coupled with a thermal FE model, which computes the heat flow characteristics of the SLM process. The developed model considers the powder-to-liquid-to-solid transformation, tracks the interaction between several melt pools within a melted track, and several tracks within various layers. It was found that the calculated temperature profiles as well as the simulated microstructures bared close resemblance with SLM fabricated AA-2024 samples. The developed model was capable of predicting melt pool cooling and solidification rates, the type of microstructure obtained, the size of the melt pool (with 14% error) and the heat affected zone, average grain size number (with 12% error) and the growth competition present in microstructures of components manufactured via SLM. Keywords: Grain structure, Cellular Automata, Finite Element, Selective Laser Melting, Additive Manufacturing

Mucopolysaccharidosis type 1 (MPS-1), also known as Hurler’s disease, is a congenital metabolic disorder caused by a mutation in the alpha-L-iduronidase (IDUA) gene, which results in the loss of lysosomal enzyme function for the degradation of glycosaminoglycans. Here, we demonstrate the proof of concept of ex vivo gene editing therapy using induced pluripotent stem cell (iPSC) and CRISPR/Cas9 technologies with MPS-1 model mouse cell. Disease-affected iPSCs were generated from Idua knockout mouse embryonic fibroblasts, which carry a disrupting neomycin-resistant gene cassette (Neor) in exon VI of the Idua gene. Double guide RNAs were used to remove the Neor sequence, and various lengths of donor templates were used to reconstruct the exon VI sequence. A quantitative PCR-based screening method was used to identify Neor removal. The sequence restoration without any indel mutation was further confirmed by Sanger sequencing. After induced fibroblast differentiation, the gene-corrected iPSC-derived fibroblasts demonstrated Idua function equivalent to the wild-type iPSC-derived fibroblasts. The Idua-deficient cells were competent to be reprogrammed to iPSCs, and pluripotency was maintained through CRISPR/CAS9-mediated gene correction. These results support the concept of ex vivo gene editing therapy using iPSC and CRISPR/Cas9 technologies for MPS-1 patients.

This paper focuses on the aerodynamics and design of an unmanned aerial vehicle (UAV) based on solar cells as a main power source. The procedure includes three phases: the conceptual design, preliminary design, and a computational fluid dynamics analysis of the vehicle. One of the main disadvantages of an electric UAV is the flight time; in this sense, the challenge is to create an aerodynamic design that can increase the endurance of the UAV. In this research, the flight mission starts with the attempt of the vehicle design to get at the maximum altitude; then, the UAV starts to glide and battery charge recovery is achieved due to the solar cells. A conceptual design is used, and the aerodynamic analysis is focused on a UAV as a gliding vehicle, with the calculations starting with the estimation of weight and aerodynamics and finishing this stage with the best glide angle. In fact, the aerodynamic analysis is obtained for a preliminary design; this step involves the wing, fuselage, and empennage of the UAV. In order to achieve the preliminary design, an estimation of aerodynamic coefficients, along with computational fluid dynamics analysis, is performed.

Quick Response QR barcode detection in nonarbitrary environment is still a challenging task despite many existing applications for finding 2D symbols. The main disadvantage of recent applications for QR code detection is a low performance for rotated and distorted single or multiple symbols in images with variable illumination and presence of noise. In this paper, a particular solution for QR code detection in uncontrolled environments is presented. The proposal consists in recognizing geometrical features of QR code using a binary large object- (BLOB-) based algorithm with subsequent iterative filtering QR symbol position detection patterns that do not require complex processing and training of classifiers frequently used for these purposes. The high precision and speed are achieved by adaptive threshold binarization of integral images. In contrast to well-known scanners, which fail to detect QR code with medium to strong blurring, significant nonuniform illumination, considerable symbol deformations, and noising, the proposed technique provides high recognition rate of 80%–100% with a speed compatible to real-time applications. In particular, speed varies from 200 ms to 800 ms per single or multiple QR code detected simultaneously in images with resolution from 640 × 480 to 4080 × 2720, respectively.

Intranasal meningoencephaloceles have historically been managed by neurosurgeons, although their main clinical manifestations are rhinological. Recent advances in endoscopic skull base surgery has significantly improved the treatment of these lesions and consequently diminished appreciable surgical morbidity. We report an ethmoidal meningoencephalocele case operated on by endonasal endoscopic approach for removal of the lesion and reconstructing the associated skull base. From this experience, we conclude that removal of the lesion and watertight closure of the skull base irrespective of the size of the mass and anterior skull base defect are the operation’s most important aspects.

The development of university students’ skills to successfully produce scientific documents has been a recurring topic of study in academia. This paper analyzes the implementation of a training experience using a digital environment mediated by video content materials starring humanoid robots. The research aimed to scale complex thinking and its sub-competencies as a hinge to strengthen basic academic research skills. Students from Colombia, Ecuador, and Mexico committed to preparing a scientific document as part of their professional training participated. A pretest to know their initial level of perception, a posttest to evaluate if there was a change, and a scientific document the students delivered at the end of the training experience comprised the methodology to demonstrate the improvement of their skills. The results indicated students’ perceived improvement in the sub-competencies of systemic, creative, scientific, and innovative thinking; however, their perceptions did not align with that of the tutor who reviewed the delivered scientific product. The conclusion was that although the training experience helped strengthen the students’ skills, variables that are determinants for a student to develop the knowledge necessary to prepare scientific documents and their derived products remain to be analyzed. [ABSTRACT FROM AUTHOR]

Introduccion La derivacion ventriculo peritoneal es uno de los procederes mas frecuentes y relativamente sencillos realizado en neurocirugia (1,2). Sin embargo, estudios recientes reportan hasta un 32% de disfunciones del [...], The following papers is a technical note about a new endoscopic access to lateral ventricle through occipital horn to place ventricles catheters, 20 patient was operated using Deck System of endoscopy with lens of 30 grades, 2,7 mm of diameter and 30 cm of larger, sheets and working canals including. CT scan was performing 24 hours after surgery and optimal position was obtained in 95%. Median distance from occipital bon to frontal horn of the ventricles was 10,5 cm. Any patient present dysfunction of the system and only one patient had a hematoma of the surgical area. Key words: Ventricular- peritoneal shunt, ventricular catheters, occipital horn. El siguiente trabajo constituye una nota tecnica sobre un nuevo proceder endoscopico de colocacion de cateteres ventriculares permanente a traves del cuerno occipital. Se colocaron 20 cateteres permanentes utilizando el sistema DECK con un endoscopio Hopkins II de 30[degrees], diametro 2,7 mm y longitud 30 cm, con vainas y canales de trabajos. La posicion del cateter fue evaluada por tomografia de craneo realizada a las 24 horas de la cirugia, obteniendose una posicion a (optima) en el 95% de los casos, con una distancia promedio de 10,5 cm desde la tabla externa del hueso occipital al cuerno frontal. En ninguno de los casos disfunciono el sistema derivativo y un solo paciente presento como complicacion un hematoma del lecho quirurgico. Palabras clave: Derivacion ventriculo-peritoneal, cateteres ventriculares, cuerno occipital.