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Abstract Background Many patients with COVID-19 present the so-called post-acute sequelae of COVID-19 such as fatigue, post-stress discomfort, dyspnea, headache, pain mental impairment, incapacity to perform daily physical tasks ant exercise intolerance. This study aims to investigate the effects of different exercise programs on physical and mental fitness, physical condition and biomarkers of the immune system and oxidative stress in older patients with post-COVID-19 sequelae. Methods The sample will be made up of 120 eligible participants, over the age of 60 years who have had COVID-19 disease and are survivors and present persistent COVID-19 symptomatology diagnosed by the corresponding physician. The participants will be randomly assigned to the experimental groups: supervised endurance group (SEG, n = 30), supervised strength group (SSG, n = 30), supervised concurrent group (SCG, n = 30), which will perform the corresponding exercise program 3 days a week compared to the control group (CG, n = 30), which will not carry out a supervised exercise program. The design of this project will include measurements of four relevant dimensions; 1) Cardiorespiratory fitness; 2) Muscle fitness; 3) Pain and mental health; and 4) Biomarkers of inflammation and oxidative stress. Conclusions The results of this study will provide insights into the effects of different exercise programs on physical and mental fitness, physical condition and biomarkers of the immune system and oxidative stress in older patients with post-COVID-19 sequelae. These findings may be the basis for the formulation of health plans and rehabilitation programs that allow healthy aging and a reduction in the associated morbidity in patients with post-COVID-19 sequelae. Trial registration NCT05848518. Registered on May 8, 2023.

This paper presents a fault detection and estimation method based on a proportional-integral observer applied to a three-degree-of-freedom mechanical crane. Faults are common in this system and can provoke oscillations that generate a loss of performance and stability. A convex linear parameter varying approach is proposed to stabilize the crane and detect and isolate actuator faults to guarantee the crane’s performance. The linear matrix inequalities obtained from candidate Lyapunov functions give sufficient conditions to guarantee the fault estimation method. Finally, numerical simulations are proposed to illustrate the method’s performance and applicability.

Abstract Objective: to explore and describe how perioperative nurses assess and interpret the child’s behavior before entering the operating room, identifying the strategies they use to reduce anxiety and the proposals for improvements. Method: descriptive qualitative study using semi-structured interviews and participant observation of daily routines. Thematic analysis of data. This study follows the recommended criteria for publication of articles of the qualitative methodology Consolidated Criteria for Reporting Qualitative Research. Results: four topics emerged from the data: a) assessment of anxiety or close communication with the child and their family; b) evaluating what was observed; c) managing anxiety and d) improving the assessment or proposals for improvements in daily practice. Conclusion: nurses assess anxiety in their daily practice through observation using their clinical judgment. The nurse’s experience is decisive for the appropriate assessment of the preoperative anxiety in child. Insufficient time between waiting and entering the operating room, lack of information from child and their parents about the surgical procedure, and parental anxiety make it difficult to assess and properly manage anxiety.

Microplastics are plastic particles smaller than 5 mm found in the environment, which can cause health problems for aquatic organisms and humans, being classified as emerging pollutants. In Guatemala, Lake Amatitlán is one of the most polluted lakes as it receives discharges of wastewater, treated and untreated, as well as other waste from Guatemala City and other major urban populations. In a recent study, microplastics were found in sediments in Lake Amatitlán, so it was necessary to determine whether the lake's fish are affected by these pollutants, which can be harmful to their health. This research aimed to determine the microplastics in fish from Lake Amatitlán, for which 65 specimens of Nile tilapia (Oreochromis niloticus) were collected in October and December 2020, and January 2021. The collected fish were dissected in the laboratory, where the number and type of microplastics were analyzed in the digestive tract, after their separation by digestion and filtration. Lines or fibers were the most common type of microplastics, found in 63 specimens (96.9% of the analyzed specimens), ranging from 0 to 27 lines/fibers per individual. The frequency of other types of microplastics found were 0-3 fragments/individual, 0-2 films/individual, and 0-4 foams/individual, while microspheres were not found in any specimen. The presence of microplastics in tilapia from Lake Amatitlán is an indicator of contamination in the lake by pollutants that could affect the trophic network and represents a risk for the fish consumers, requiring the attention of environmental and health authorities.

Este trabajo propone un esquema de detección y localización de fallas en los actuadores de un vehículo aéreo no tripulado (VANT) del tipo cuadrirrotor. Para ello, se considera un enfoque basado en datos haciendo uso de técnicas de aprendizaje de máquina. En este enfoque se construye un modelo implícito del sistema a través de la información proporcionada por los sensores del VANT. Primero, a través de un plataforma de vuelo de tipo giroscópica, se captan las vibraciones correspondientes a la orientación, posición angular y aceleración lineal cuando el vehículo se encuentra en vuelo estacionario en condiciones nominales. Estos datos se procesan mediante Análisis en Componentes Principales (PCA) para la extracción de características. Posteriormente, se induce una falla a los actuadores a través de un recorte en cada una de las hélices del VANT que ocasionan una reducción del empuje generado por los rotores. Estos datos se proyectan también al subespacio de componentes principales y se comparan con los datos nominales. Para discernir entre los datos nominales y los datos cuando el vehículo presenta falla, se emplea el estadístico T2 de Hotelling. Finalmente, el desarrollo se complementa con los algoritmos de clasificación de k-vecinos más cercanos (k-NN) y de máquina de vectores de soporte (SVM). Los resultados muestran una tasa de clasificación correcta del 89.6 % (k-NN) y 92.4 %(SVM) respectivamente para 423 conjuntos de datos de validación.

This paper presents a pressure management technique for the reduction of leaks considering as a case study a branched water distribution system. The proposed technique is based on the detection and location of the leak using a genetic algorithm (GA) and pressure control using a Linear Quadratic Regulator (LQR). The validation of the proposed method uses measured pressure and flow data from a laboratory-scale water distribution system and its dynamic model. [ABSTRACT FROM AUTHOR]

Many studies have shown that patients with autoimmune disease present a hypoactive hypothalamic‐pituitary‐adrenal (HPA) axis, but the results are controversial. Our objective was to study differences in stress response axis activity between patients with autoimmune disease and healthy people. The study sample consisted of 97 women divided into four groups: 37 healthy women (HW), 21 with systemic lupus erythematosus (SLE), 21 with Sjögren's syndrome (SS), and 18 with systemic sclerosis (SSc). After being exposed to a stress task, participants' skin conductance and salivary cortisol levels were measured in order to assess their response to psychological stress. Diurnal cortisol concentrations were assessed by measuring salivary cortisol in samples collected five times over one day. In addition, self‐administered questionnaires were used to assess psychological variables. A time × group interaction effect was found (p = 0.003) in salivary cortisol secretion in response to stressful challenge. The healthy group presented normal activation, the SS and SLE groups showed no activation, and the SSc group presented a similar activation pattern to the HW group, except at the time of recovery. Total cortisol production (AUCg) was higher in the SSc group than in the HW group (p = 0.001). Differences were also observed in the cortisol AUCg collected over one day between healthy women and patients with SLE (p = 0.004) as well as with SSc (p = 0.001): women with SLE and SSc presented higher total hormone production than healthy women. Patients with autoimmune disease present a different HPA axis response, which may contribute to the harmful effects of stress in these diseases. [ABSTRACT FROM AUTHOR]

ABSTRACT The objective of this study was to determine and compare the chemical composition; oxidation indicators; ether extract (EE) digestibility; and digestible, metabolizable, and net energy (DE, ME, and NE, respectively) content of distillers corn oil (DCO) from Brazil (CBR) and the United States (CUS), with refined (RSB) and degummed soybean oil (DSB) from Brazil offered to pigs. Fifty crossbred barrows (23.1±3.4 kg body weight) were fed a corn-soybean meal basal diet, or diets composed of 90% basal diet and 10% of one of the four oil sources (CBR, CUS, RSB, or DSB). Pigs were fed an amount of their respective experimental diets equivalent to 2.8 times the maintenance DE requirement for 9 d (sequentially 7 d for adaptation and 2 d for partial collection of feces). Distillers corn oil from Brazil contained lower linoleic acid (47.4%) than CUS (53.9%), RSB (54.2%), and DSB (51.5%), but greater contents of oleic (32.1%) and palmitic (14.6%) acids compared to CUS (27.0 and 12.9%), RSB (22.9 and 11.2%), and DSB (23.5 and 11.2%). The moisture and unsaponifiable contents of CBR (0.17 and 1.64%) and CUS (0.20 and 1.64%) were similar, but greater than the values found for RSB (0.05 and 1.20%) and DSB (0.12 and 1.02%). The anisidine value, free fatty acid content, and acidity of DCO samples were higher than soybean oils. The peroxide value and thiobarbituric reactive substances content increased in the oil samples over time. The apparent total tract digestibility (ATTD) of gross energy and the DE, ME and NE values of the oils did not differ among oil sources and ranged from 87.8 to 91.5%, and from 8280 to 8630, 8139 to 8459, and 7162 to 7444 kcal/kg, respectively. The ATTD of EE was greater in RSB and DSB than for CBR, but similar to CUS. The DCO produced in Brazil is an excellent energy source for pigs, with DE, ME, and NE values similar to those of DCO from the US and soybean oils.

El objetivo de esta investigación fue identificar los elementos del patrimonio biocultural de los ch’oles de Tacotalpa, Tabasco. A través de la realización de entrevistas estructuradas, observación participante y diálogos abiertos, se concluyó que los recursos naturales más valorados son: el paisaje, el agua, la milpa, las plantas y los animales. Se mencionaron problemas de disponibilidad de estos recursos y se destacaron entre los aspectos culturales más importantes los valores, las tradiciones y costumbres y la lengua indígena. Los ch’oles de esta región conservan los elementos de su patrimonio biocultural y entre las prácticas socioculturales que más realizan se encuentran: la mayordomía y los rituales de curación, de petición de lluvia y de bendición de semillas.

This work presents the reconstruction of the pressure head map of a water distribution system (WDS). This approach relies on historical data collected from a reduced number of sensors placed at some nodes of the WDS. Thus, a Gaussian regression process is then applied to estimate the pressure head at those nodes without a sensor, which allows the reconstruction of the pressure map for the whole network. Then, for leak diagnosis purposes, a dataset of pressure head maps of the WDN is created considering leaky scenarios, and a correlation method is applied to estimate the leak location. Then, for clarity, the Hanoi network is used to evaluate the performance of this leak diagnosis strategy in a simulation environment, assuming the availability of only three sensors. The results showed the potential for pressure head map reconstruction and leak localization. [ABSTRACT FROM AUTHOR]

Osteosarcoma is one of the most common types of bone cancers among paediatric patients. Despite the advances made in surgery, chemo-, and radiotherapy, the mortality rate of metastatic osteosarcoma remains unchangeably high. The standard drug combination used to treat this bone cancer has remained the same for the last 20 years, and it produces many dangerous side effects. Through history, from ancient to modern times, nature has been a remarkable source of chemical diversity, used to alleviate human disease. The application of modern scientific technology to the study of natural products has identified many specific molecules with anti-cancer properties. This review describes the latest discovered anti-cancer compounds extracted from traditional medicinal plants, with a focus on osteosarcoma research, and on their cellular and molecular mechanisms of action. The presented compounds have proven to kill osteosarcoma cells by interfering with different pathways: apoptosis induction, stimulation of autophagy, generation of reactive oxygen species, etc. This wide variety of cellular targets confer natural products the potential to be used as chemotherapeutic drugs, and also the ability to act as sensitizers in drug combination treatments. The major hindrance for these molecules is low bioavailability. A problem that may be solved by chemical modification or nano-encapsulation.

This paper presents the design of a maximum power point-tracking (MPPT) technique for DC–DC converters that are used in energy-harvesting systems based on thermoelectric generators. This technique is based on the analysis of the characteristics of the converter to measure the open-circuit voltage indirectly. The main contribution of this article is that the algorithm measures the voltage at the maximum power point without the need to disconnect the source of the circuit, as happens when the fractional open-circuit voltage (FOCV) technique is used. The algorithm is based on a predetermined initial duty cycle, which is applied to the circuit, and the input voltage and input current are read. With these values, the open-circuit voltage and short-circuit current are calculated with equations obtained from the circuit. Then, it calculates the duty cycle at the maximum power point and applies it to the circuit. If this duty cycle does not obtain the maximum power from the circuit, the algorithm starts a second stage based on fuzzy logic to calculate an increase or decrease in the duty cycle. The designed technique was evaluated using a topology based on a DC–DC flyback converter variant and was compared with the P&O technique and obtained better results. The designed technique provides between 3.9% and 5.6% more power to the load than the P&O technique in a 20 W system.