Kinematic analysis of a lower limb to determine the center of rotation of the knee at the sagittal plane.

En esta investigación se establece una metodología que permite describir el movimiento de miembros inferiores usando cadenas cinemáticas cerradas. Este análisis es realizado con el objetivo de determinar la posición del centro de rotación (CR) de la rodilla localizado en el plano sagital. Un paciente sano y sin antecedentes patológicos realizó pruebas de flexión-extensión con uno de sus miembros inferiores. Cuando el paciente realizo el movimiento articular (la flexo-extensión) un dispositivo de video y un programa (World In motion v4.0) determinan la posición de cuatro marcadores pasivos ubicados en el miembro inferior. Los datos obtenidos de los marcadores son utilizados en un modelo propuesto que permite localizar la posición del CR de la rodilla. En este estudio se concluye que el CR de la rodilla presenta movimiento relativo respecto a un punto fijo marcado en un miembro inferior. Los resultados comprueban que el CR de la rodilla delimitado en el plano sagital no presenta comportamiento de una junta completa (junta con un grado de libertad) como ha sido presentado en otros estudios. Abstract A methodology is established in this research which permits to describe the movement of a lower limb using closed kinematic chains. This analysis is developed with the aim to determine the location of the center of rotation (CR) of the knee joint in the sagittal plane. Flexion-extension tests were carried out on one of the lower limbs of a healthy patient without pathological antecedents. When the patient does articular movement (flexion-extension), a video equipment and a software determine the position of four passive markers installed on the lower limb. The information obtained from the markers is applied to the proposed model which allows to locate the center of rotation of the knee joint. Hence it was concluded that the CR of the knee joint undergoes a relative movement with respect to the fixed point marked on the lower limb. The results prove that the knee joint established in the sagittal plane does not show the behavior of a complete joint (a joint with one degree of freedom) as it has been described in other studies

Análisis del proceso de deshidratación de cacao para la disminución del tiempo de secado

O cacau é um dos produtos que demanda o mercado agrícola internacional; algumas companhias investiram desde seus inícios em pesquisa e desenvolvimento com o fim de obter novos produtos. Alguns fatores aumentam os custos nos produtos derivados do cacau, o qual pode ser atribuído a condições do mercado (oferta e procura), processos de transformação do cacau, processos e procedimentos agrícolas, entre outros. Este estudo enfoca-se em um processo de transformação industrial que habitualmente é uma etapa final de uma série de operações para conseguir grãos secos de cacau. Determinadas variáveis, como o tempo, temperatura e umidade, estabelecem a efetividade do secado de cacau. Esta pesquisa sugere a possibilidade de diminuir o tempo de secado industrial sem afetar as propriedades organolépticas, manipulando a umidade e a temperatura. Para esta proposta se realizaram provas de secado experimental e análise computacional utilizando o método de elementos finitos para estudar o processo de secado.El cacao es uno de los productos que demanda el mercado agrícola internacional; algunas compañías han invertido desde sus inicios en investigación y desarrollo, con el fin de obtener nuevos productos. Algunos factores incrementan los costos en los productos derivados del cacao, lo que puede ser atribuido a condiciones del mercado (oferta y demanda), procesos de transformación del cacao, procesos y procedimientos agrícolas, entre otros. Este estudio se enfoca en un proceso de transformación industrial que habitualmente es una etapa final de una serie de operaciones para conseguir granos secos de cacao. Determinadas variables como el tiempo, temperatura y humedad establecen la efectividad del secado de cacao. Esta investigación sugiere la posibilidad de disminuir el tiempo de secado industrial sin afectar las propiedades organolépticas, modificando la humedad y la temperatura. Para esta propuesta se realizaron pruebas de secado experimental y análisis computacional utilizando el método de elementos finitos para estudiar el proceso de secado.Cocoa is one of the products demanded by the international agricultural market; some multinational companies have invested from its beginnings in research and development, in order to obtain new products. Some factors increase the costs in cocoa-based products, which can be attributed to market conditions (supply and demand), cocoa transformation process, agricultural processes and procedures, among others. This study focuses on a process of industrial transformation that is usually a final step in a series of operations to get dried cocoa beans. Certain variables such as time, temperature, and humidity establish the effectiveness of drying of cocoa. This research suggests the possibility of reducing industrial drying time without affecting the organoleptic properties, changing humidity and temperature. For this proposal experimental tests of drying and computational analysis, using the finite element method to study the drying process, were carried out

ANÁLISIS DEL PROCESO DE DESHIDRATACIÓN DE CACAO PARA LA DISMINUCIÓN DEL TIEMPO DE SECADO (ANALYSIS OF THE COCOA DEHYDRATION PROCESS FOR REDUCING DRYING TIME)

El cacao es uno de los productos que demanda el mercadoagrícola internacional; algunas compañías han invertido desde sus inicios eninvestigación y desarrollo, con el fin de obtener nuevos productos. Algunosfactores incrementan los costos en los productos derivados del cacao, lo quepuede ser atribuido a condiciones del mercado (oferta y demanda), procesos detransformación del cacao, procesos y procedimientos agrícolas, entre otros.Este estudio se enfoca en un proceso de transformación industrial quehabitualmente es una etapa final de una serie de operaciones para conseguirgranos secos de cacao. Determinadas variables como el tiempo, temperatura y humedadestablecen la efectividad del secado de cacao. Esta investigación sugiere laposibilidad de disminuir el tiempo de secado industrial sin afectar laspropiedades organolépticas, modificando la humedad y la temperatura. Para estapropuesta se realizaron pruebas de secado experimental y análisis computacionalutilizando el método de elementos finitos para estudiar el proceso de secado.El cacao es uno de los productos que demanda el mercadoagrícola internacional; algunas compañías han invertido desde sus inicios eninvestigación y desarrollo, con el fin de obtener nuevos productos. Algunosfactores incrementan los costos en los productos derivados del cacao, lo quepuede ser atribuido a condiciones del mercado (oferta y demanda), procesos detransformación del cacao, procesos y procedimientos agrícolas, entre otros.Este estudio se enfoca en un proceso de transformación industrial quehabitualmente es una etapa final de una serie de operaciones para conseguirgranos secos de cacao. Determinadas variables como el tiempo, temperatura y humedadestablecen la efectividad del secado de cacao. Esta investigación sugiere laposibilidad de disminuir el tiempo de secado industrial sin afectar laspropiedades organolépticas, modificando la humedad y la temperatura. Para estapropuesta se realizaron pruebas de secado experimental y análisis computacionalutilizando el método de elementos finitos para estudiar el proceso de secado

Analysis of the cocoa dehydration process for reducing drying time

El cacao es uno de los productos que demanda el mercado agrícola internacional; algunas compañías han invertido desde sus inicios en investigación y desarrollo, con el fin de obtener nuevos productos. Algunos factores incrementan los costos en los productos derivados del cacao, lo que puede ser atribuido a condiciones del mercado (oferta y demanda), procesos de transformación del cacao, procesos y procedimientos agrícolas, entre otros. Este estudio se enfoca en un proceso de transformación industrial que habitualmente es una etapa final de una serie de operaciones para conseguir granos secos de cacao. Determinadas variables como el tiempo, temperatura y humedad establecen la efectividad del secado de cacao. Esta investigación sugiere la posibilidad de disminuir el tiempo de secado industrial sin afectar las propiedades organolépticas, modificando la humedad y la temperatura. Para esta propuesta se realizaron pruebas de secado experimental y análisis computacional utilizando el método de elementos finitos para estudiar el proceso de secado.Cocoa is one of the products demanded by the international agricultural market; some multinational companies have invested from its beginnings in research and development, in order to obtain new products. Some factors increase the costs in cocoa-based products, which can be attributed to market conditions (supply and demand), cocoa transformation process, agricultural processes and procedures, among others. This study focuses on a process of industrial transformation that is usually a final step in a series of operations to get dried cocoa beans. Certain variables such as time, temperature, and humidity establish the effectiveness of drying of cocoa. This research suggests the possibility of reducing industrial drying time without affecting the organoleptic properties, changing humidity and temperature. For this proposal experimental tests of drying and computational analysis, using the finite element method to study the drying process, were carried out

Optimizing Harvesting Efficiency: Development and Assessment of a Pneumatic Air Jet Excitation Nozzle for Delicate Biostructures in Food Processing

This study presents a new pneumatic air jet excitation nozzle, specifically designed for food processing applications. The device, which uses compressed air equipment and a precision solenoid valve, controls air discharge through a parametric air jet nozzle. Tests showed that the device could achieve shooting frequencies in the 40–45 Hz range, with operational pressures between 5 and 7 bar. A sensor system was used to measure the force generated by the device at different frequencies and pressures. Using the Design of Experiments (DOE) methodology, we identified optimal cavity designs for 5 and 6 bar pressures. These designs outperformed others in generating uniform force and maintaining consistent vibration voltage behavior. This highlights the efficacy of our approach in enhancing device performance under different conditions. The device’s practical application in food processing was demonstrated, particularly in delicate tasks such as the selective harvesting of sensitive crops like coffee fruits. The precise vibrations generated by the device could potentially enhance harvesting efficiency while significantly reducing mechanical damage to plants. The results position the device as a compelling proof of concept, offering an alternative method for exciting biostructures in food processing. This device opens up new possibilities in agricultural and biological fields, providing a non-intrusive and practical approach to manipulating and interacting with delicate, contactless structures, with a specific focus on improving food processing efficiency and quality

Evaluation and Performance of a Positive Airway Pressure Device (CPAP-AirFlife™): A Randomized Crossover Non-Inferiority Clinical Study in Normal Subjects

Background and Objectives: During the COVID-19, the demand for non-invasive ventilatory support equipment significantly increased. In response, a novel non-invasive ventilatory support model called CPAP-AirFlife™ was developed utilizing existing technologies. This model offers technological advantages, including an aerosol-controlled helmet suitable for high-risk environments such as ambulances. Additionally, it is cost-effective and does not require medical air, making it accessible for implementation in low-level hospitals, particularly in rural areas. This study aimed to assess the efficacy of CPAP-AirFlife™ by conducting a non-inferiority comparison with conventional ventilation equipment used in the Intensive Care Unit. Materials and Methods: A clinical study was conducted on normal subjects in a randomized and sequential manner. Parameters such as hemoglobin oxygen saturation by pulse oximetry, exhaled PCO2 levels, vital signs, and individual tolerance were compared between the CPAP-AirFlife™ and conventional equipment. The study population was described in terms of demographic characteristics and included in the analysis. Results: It was shown that the CPAP-AirFlife™ was not inferior to conventional equipment in terms of efficacy or tolerability. Hemoglobin oxygen saturation levels, exhaled PCO2 levels, vital signs, and individual tolerance did not significantly differ between the two models. Conclusions: The findings suggest that CPAP-AirFlife™ is a practical and cost-effective alternative for non-invasive ventilatory support. Its technological advantages, including the aerosol-controlled helmet, make it suitable for high-risk environments. The device’s accessibility and affordability make it a promising solution for implementation in low-level hospitals, particularly in rural areas. This study supports using CPAP-AirFlife™ as a practical option for non-invasive ventilatory support, providing a valuable contribution to respiratory care during the COVID-19 pandemic and beyond

Reproductive events of birds from Southern Ecuador

ABSTRACTUnderstanding the reproductive biology of birds is crucial for comprehending their natural history and implementing effective conservation practices. However, there is limited information available on the reproductive behavior of many bird species in Southern Ecuador. This manuscript contributes to the knowledge of the reproductive biology of 127 bird species from the region, providing detailed information on five species whose reproductive traits were previously undocumented (Urochroa leucura, Agriornis albicauda, Turdus maranonicus, Spinus olivaceus, and Stilpnia viridicollis), as well as reproductive data on 12 species for which information was scarce (Heliangelus viola, Chalcostigma stanleyi, Eriocnemis luciani, Coeligena iris, Megascops koepckeae, Conopophaga castaneiceps, Sclerurus obscurior, Leptasthenura andicola, Ochthoeca fumicolor, Geospizopsis unicolor, Catamenia inornata, and Sporophila castaneiventris). Furthermore, we include additional information on the reproductive biology of 110 species that have already been documented. This manuscript provides the most up-to-date inventory of the reproductive behavior of bird species in Southern Ecuador, which can aid in the development of better conservation strategies in the region

Clinical characterization of data-driven diabetes subgroups in Mexicans using a reproducible machine learning approach

Introduction Previous reports in European populations demonstrated the existence of five data-driven adult-onset diabetes subgroups. Here, we use self-normalizing neural networks (SNNN) to improve reproducibility of these data-driven diabetes subgroups in Mexican cohorts to extend its application to more diverse settings.Research design and methods We trained SNNN and compared it with k-means clustering to classify diabetes subgroups in a multiethnic and representative population-based National Health and Nutrition Examination Survey (NHANES) datasets with all available measures (training sample: NHANES-III, n=1132; validation sample: NHANES 1999–2006, n=626). SNNN models were then applied to four Mexican cohorts (SIGMA-UIEM, n=1521; Metabolic Syndrome cohort, n=6144; ENSANUT 2016, n=614 and CAIPaDi, n=1608) to characterize diabetes subgroups in Mexicans according to treatment response, risk for chronic complications and risk factors for the incidence of each subgroup.Results SNNN yielded four reproducible clinical profiles (obesity related, insulin deficient, insulin resistant, age related) in NHANES and Mexican cohorts even without C-peptide measurements. We observed in a population-based survey a high prevalence of the insulin-deficient form (41.25%, 95% CI 41.02% to 41.48%), followed by obesity-related (33.60%, 95% CI 33.40% to 33.79%), age-related (14.72%, 95% CI 14.63% to 14.82%) and severe insulin-resistant groups. A significant association was found between the SLC16A11 diabetes risk variant and the obesity-related subgroup (OR 1.42, 95% CI 1.10 to 1.83, p=0.008). Among incident cases, we observed a greater incidence of mild obesity-related diabetes (n=149, 45.0%). In a diabetes outpatient clinic cohort, we observed increased 1-year risk (HR 1.59, 95% CI 1.01 to 2.51) and 2-year risk (HR 1.94, 95% CI 1.13 to 3.31) for incident retinopathy in the insulin-deficient group and decreased 2-year diabetic retinopathy risk for the obesity-related subgroup (HR 0.49, 95% CI 0.27 to 0.89).Conclusions Diabetes subgroup phenotypes are reproducible using SNNN; our algorithm is available as web-based tool. Application of these models allowed for better characterization of diabetes subgroups and risk factors in Mexicans that could have clinical applications