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The objective of this project was to compare two non-parametric classification methods (“Support Vector Machine” – SVM and “Artificial Neural Networks” – ANN) of road regions in high spatial resolution images and associated with data from Airborne Laser Scanning. The study aims to verify what kind of influence the layers of attributes have on the performance from respective classifiers: SVM and RNA. Our method based on tests of this classifiers on 4 bands of airborne images and normalization of the digital surface model (DSM) for showing only information on objects height in relation to ground and not of these in relation to the ground and relief, generating band 5. The samples were used to train chosen non-parametric classifiers (training sets for each different input image/landscape). All classifications had the same set of training samples and the same classification parameters. The optimal parameters for classifications were obtained through the existing library in the Weka mining package: LibSVM and LibMultiLayerPerceptron. Our results demonstrated the existence of a direct relationship between the elevation band of the targets in relation to the terrain (band 05) with the improvement of their performance and lower degree of between bands correlation can also be considered a factor that has a positive influence. As for Neural Networks, the experiment results demonstrate that the presence of the near infrared band (band 04) was decisive for the performance improving of certain combinations in relation to others.

Abstract Background Outstanding exercise performance has been associated with an exacerbated vagal outflow. Nevertheless, during high-altitude hypobaric-hypoxia (HH), there is a baroreflex-dependent parasympathetic withdrawal and exercise performance deterioration. Notably, vagal control is pivotal in exercise performance, and exogenous oxytocin (OXY) administration has been shown to enhance parasympathetic drive; however, no evidence shows their role in exercise performance during HH. Then, this study aimed to examine the effect of prolonged exogenous oxytocin (OXY) administration on exercise performance during hypobaric hypoxia (HH) in rats. Results A vehicle group (n = 6) and an OXY group (n = 6) performed incremental exercise and baroreflex tests during both normobaric normoxia (NN) and HH (PO2: 100 mmHg, simulated 3,500 m) prior (pre-) and after (post-) 14 days of administration. The results showed that at pre-, there were no significant differences in exercise performance between the two groups, while at post-, the OXY group exhibited similar performance between NN and HH, while the Vehicle group maintained a significant decline in performance at HH compared to NN. At post-, the Vehicle group also demonstrated a reset in the baroreflex and a worse bradycardic response in HH, which was reversed in the OXY group, while the hypoxic ventilatory response was similar in both groups. Conclusion The findings suggest prolonged OXY administration prevents impaired exercise performance and vagal control during short-term HH.

Abstract Background Dipeptidyl peptidase 4 (DPP-4) plays a crucial role in breaking down various substrates. It also has effects on the insulin signaling pathway, contributing to insulin resistance, and involvement in inflammatory processes like obesity and type 2 diabetes mellitus. Emerging effects of DPP-4 on bone metabolism include an inverse relationship between DPP-4 activity levels and bone mineral density, along with an increased risk of fractures. Main body The influence of DPP-4 on bone metabolism occurs through two axes. The entero-endocrine-osseous axis involves gastrointestinal substrates for DPP-4, including glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptides 1 (GLP-1) and 2 (GLP-2). Studies suggest that supraphysiological doses of exogenous GLP-2 has a significant inhibitory effect on bone resorption, however the specific mechanism by which GLP-2 influences bone metabolism remains unknown. Of these, GIP stands out for its role in bone formation. Other gastrointestinal DPP-4 substrates are pancreatic peptide YY and neuropeptide Y—both bind to the same receptors and appear to increase bone resorption and decrease bone formation. Adipokines (e.g., leptin and adiponectin) are regulated by DPP-4 and may influence bone remodeling and energy metabolism in a paracrine manner. The pancreatic-endocrine-osseous axis involves a potential link between DPP-4, bone, and energy metabolism through the receptor activator of nuclear factor kappa B ligand (RANKL), which induces DPP-4 expression in osteoclasts, leading to decreased GLP-1 levels and increased blood glucose levels. Inhibitors of DPP-4 participate in the pancreatic-endocrine-osseous axis by increasing endogenous GLP-1. In addition to their glycemic effects, DPP-4 inhibitors have the potential to decrease bone resorption, increase bone formation, and reduce the incidence of osteoporosis and fractures. Still, many questions on the interactions between DPP-4 and bone remain unanswered, particularly regarding the effects of DPP-4 inhibition on the skeleton of older individuals. Conclusion The elucidation of the intricate interactions and impact of DPP-4 on bone is paramount for a proper understanding of the body's mechanisms in regulating bone homeostasis and responses to internal stimuli. This understanding bears significant implications in the investigation of conditions like osteoporosis, in which disruptions to these signaling pathways occur. Further research is essential to uncover the full extent of DPP-4's effects on bone metabolism and energy regulation, paving the way for novel therapeutic interventions targeting these pathways, particularly in older individuals.

ABSTRACT Wheel slipping and fuel consumption are variables influenced by tire pressure, speed, ballasting, and soil surface. Once the tractor is present in all agricultural operations, knowledge of these variables is essential to achieving the most operational efficiency. This study aimed to develop an embedded system to collect data and show tractor slipping and fuel consumption in real-time via smartphone. The system was developed using prototyping platforms and validated through randomized field tests under four speeds and two terrain conditions. Three methods for determining slippage under different conditions were compared. The developed embedded system determined an agricultural tractor's slipping and fuel consumption conditions. The slip and fuel consumption rates varied depending on the type of rolling surface (ground preparations) and the tractor's operating speeds. Conventional tillage surface increased fuel demand by 6% and slippage by 17% compared to no-till rates. The proposed embedded system found similar results and could present the slipping values in the developed Android to real-time operation compared to a conventional method. This application shows both slipping and fuel consumption values over time on graphs, which can be very useful during machine operation, helping to define better configuration and reduce environmental impacts.

Abstract Histoplasmosis is caused by the fungus Histoplasma capsulatum and is often fatal for individuals with acquired immunodeficiency syndrome (AIDS). Delayed diagnosis is a major factor in worsening coinfection, as it can be mistaken for other diseases. Thus, rapid identification of Histoplasma in immunocompromised patients is essential. Molecular techniques, particularly polymerase chain reaction (PCR), were used in this study to identify H. capsulatum in patients coinfected with histoplasmosis and AIDS. Blood samples from 14 individuals with AIDS and disseminated histoplasmosis were collected and analyzed. The PCR method successfully amplified the fungal region in whole blood samples, while PCR-RFLP analysis confirmed a consistent profile in the samples. Genetic sequencing further confirmed the fungal species. Compared to clinical tests such as fungal culture and urinary antigen detection, molecular analysis proved faster, more sensitive, and cost-effective. These molecular markers can potentially be incorporated into routine diagnostics in the future. Further studies are needed to expand and enhance this diagnostic approach, particularly in patients with nonprogressive clinical forms of histoplasmosis.

Abstract Accidents involving venomous animals are a significant public health issue in Brazil, with about 140,000 cases reported annually. Pará, with its vast forests and biodiversity, experiences high incidences exacerbated by human-environment interactions. This study analyzes the temporal trend and epidemiological profile of such accidents in Pará from 2018 to 2022. A cross-sectional study using SINAN data, employing Prais-Winsten linear regression to evaluate temporal trends. Incidences were stratified by sex, age group, and accident location (rural, agricultural, work, residential, leisure). From 2018 to 2022, accidents in rural areas, particularly agricultural, increased notably, with a 40% rise overall. Males aged 20-39 years were most affected. March consistently recorded the highest cases, indicating a seasonal peak. Accidents involving venomous animals in Pará are increasing, particularly in areas of agricultural expansion. This trend highlights the need for intensified prevention efforts, public education, and effective treatment strategies, integrating public health measures and environmental management.

ABSTRACT: This study aimed to report a leiomyosarcoma associated with acute abdomen and uterine torsion in an 8-year-old, nulliparous, white-collared peccary (Tayassu tajacu) kept under human care. The animal presented a two-day clinical history of abdominal bulging, vaginal discharge, and acute abdomen. Ultrasound findings indicated an intrabdominal tumor, and an exploratory laparotomy followed by an emergency ovariohysterectomy was performed to remove the tumor. Grossly, the right horn exhibited a firm, friable tumor measuring 23cm in diameter and weighing 9.3kg. On the cut surface, the tumor drained a foul-smelling fluid and bloody content. The tumor wall was 6cm thick, dark red, firm, and had a brittle, soft, yellow fibrillar material firmly adhered to its surface. Microscopically, the lesion consisted of malignant proliferation of leiomyocytes with necrosis and hemorrhage of the endometrium and myometrium. The cytoplasm of the neoplastic cells was strongly immunopositive for vimentin and smooth muscle actin but negative for cytokeratin and desmin. Leiomyosarcoma is uncommon in Tayassuidae, and its clinicopathological presentation may be concomitant with acute abdomen, uterine torsion, and pyometra. These conditions should be included in the differential diagnosis of reproductive diseases observed in female peccaries.

Existe limitada información respecto a la reducción de la rigidez arterial entre sujetos con hipertensión y factores de riesgo para enfermedades vascular-metabólicas (i.e., de los vasos sanguíneos), donde el ejercicio induce un rol fisioterapéutico y preventivo. El objetivo del estudio fue 1) testear los efectos de 6 semanas de ejercicio concurrente de tipo alta intensidad interválico y de fuerza (CTHIIT+RT) en la la rigidez arterial de sujetos con diferente control de presión arterial y 2) comparar la magnitud de estas adaptaciones al ejercicio en diferentes variables secundarias de presión arterial y vasculares. Estudio clínico experimental aleatorizado desarrollado en seis categorías (3 controles y 3 experimentales) de adultos; controles hipertensos (CG-HTN, n=10), control presión elevada (CG-ELE, n=10), controles normotensos (CG-NT, n=10), o experimental hipertensos (ExG-HTN, n=10), presión elevada (ExG-ELE, n=10), o normotensos (ExG-NT, n=10). Los sujetos desarrollaron 6 semanas de CTHIIT+RT, donde la velocidad de onda de pulso de la arteria braquial (PWVba) (resultado primario) y variables de presión arterial, composición corporal y vasculares (resultados secundarios), fueron medidas antes y después de 6 semanas de intervención. Posterior a 6 semanas de CTHIIT+RT se observaron diferencias significativas en la magnitud de reducción de ΔPWVba en el grupo ExG-HTN versus grupo ExG-NT (diff. 0.86 m/s-1) y entre el grupo ExG-ELE vs. ExG-NT (diff. 0.76 m/s-1). En conclusión, 6 semanas de CTHIIT+RT reducen la rigidez arterial en adultos con diferente control de presión arterial, con una magnitud superior en pacientes hipertensos. Beneficios adicionales se encontraron en cese de la presión arterial elevada en los pacientes hipertensos. Palabras claves: Hipertensión arterial; Disfunción endotelial; Velocidad de onda de pulso; Índice de aumentación; índice tobillo-braquial. Abstract. There is limited information regarding the arterial stiffness decrease in subjects with hypertension and risk factors to vascular-metabolic (i.e., of blood vessels) where the exercise induces a therapeutic and preventive role. This study aimed 1) to test the effects of 6 weeks of concurrent exercise including high-intensity interval plus resistance training (CTHIIT+RT) on the arterial stiffness condition of individuals with different blood pressure controls, and 2) to compare the magnitude of exercise adaptations among different blood pressures and vascular characteristics. An experimental clinical randomized study was conducted in six categories (three controls and three experimental groups) of adults who were divided into six groups: control hypertensive (CG-HTN, n=10), control elevated blood pressure (CG-ELE, n=10), control normotensive (CG-NT, n=10), experimental hypertensive (ExG-HTN, n=10), elevated blood pressure (ExG-ELE, n=10), or normotensive (ExG-NT, n=10). The participants underwent 6 weeks of concurrent training with 5 min of high-intensity interval plus 5 min of resistance training (CTHIIT+RT), where systolic pulse wave velocity of the brachial artery (PWVba) (primary outcome) and additional secondary blood pressure, body composition, and vascular outcomes were measured before and after 6 weeks of intervention. After 6 weeks of CTHIIT+RT, significant reductions in ΔPWVba were reported in ExG-HTN vs. ExG-NT (diff. 0.86 m/s-1) and between ExG-ELE and ExG-NT (diff. 0.76 m/s-1). In conclusion, 6 weeks of CTHIIT+RT reduced arterial stiffness in adults with different blood pressure controls, but with a superior magnitude in HTN patients. Additional benefits include remission of high blood pressure in patients with hypertension. Keywords: Arterial hypertension; Endothelial dysfunction; Pulse wave velocity; Augmentation index; Ankle brachial index.

The hypoxic chemoreflex and the arterial baroreflex are implicated in the ventilatory response to exercise. It is well known that long-term exercise training increases parasympathetic and decreases sympathetic tone, both processes influenced by the arterial baroreflex and hypoxic chemoreflex function. Hypobaric hypoxia (i.e., high altitude [HA]) markedly reduces exercise capacity associated with autonomic reflexes. Indeed, a reduced exercise capacity has been found, paralleled by a baroreflex-related parasympathetic withdrawal and a pronounced chemoreflex potentiation. Additionally, it is well known that the baroreflex and chemoreflex interact, and during activation by hypoxia, the chemoreflex is predominant over the baroreflex. Thus, the baroreflex function impairment may likely facilitate the exercise deterioration through the reduction of parasympathetic tone following acute HA exposure, secondary to the chemoreflex activation. Therefore, the main goal of this review is to describe the main physiological mechanisms controlling baro- and chemoreflex function and their role in exercise capacity during HA exposure.

Accurate short- and mid-term blood glucose predictions are crucial for patients with diabetes struggling to maintain healthy glucose levels, as well as for individuals at risk of developing the disease. Consequently, numerous efforts from the scientific community have focused on developing predictive models for glucose levels. This study harnesses physiological data collected from wearable sensors to construct a series of data-driven models based on deep learning approaches. We systematically compare these models to offer insights for practitioners and researchers venturing into glucose prediction using deep learning techniques. Key questions addressed in this work encompass the comparison of various deep learning architectures for this task, determining the optimal set of input variables for accurate glucose prediction, comparing population-wide, fine-tuned, and personalized models, and assessing the impact of an individual's data volume on model performance. Additionally, as part of our outcomes, we introduce a meticulously curated dataset inclusive of data from both healthy individuals and those with diabetes, recorded in free-living conditions. This dataset aims to foster research in this domain and facilitate equitable comparisons among researchers.

Purpose: This study investigated the impact of four weeks of age-dependent detraining on army soldiers’ cardiorespiratory fitness and maximal and explosive strength. Methods: Fourteen volunteer tactical athletes participated, divided into two age groups (20 to 29 and 30 to 40 years). Before and after the detraining period, we assessed their anthropometric measurements (weight, height, body mass index, fat mass, and fat-free mass), cardiorespiratory fitness (maximal oxygen uptake [VO2max] and ventilatory thresholds [VT1 and VT2]), and kinematic properties during a single-leg counter-moving jump (CMJ) test for both the dominant and non-dominant legs. Two-way ANOVA followed by the Holm–Sidak post hoc test was used. Results: The anthropometric and cardiovascular variables did not show significant differences between the groups. However, both groups exhibited a significantly reduced maximum time and speed at the VO2max. Furthermore, the flight time and maximum height during the CMJ significantly decreased in the non-dominant leg for both age groups. Notably, the dominant leg’s concentric impulse (CI) significantly reduced during the CMJ, but this effect was observed only in the 30–40 age group. There were significant differences between the two age groups. Conclusions: Our findings suggest that four weeks of detraining negatively impacts aerobic fitness and muscular strength, independently of age. However, the dominant leg may be more susceptible to detraining effects in army soldiers aged 30–40. Furthermore, as a perspective, our results strongly suggest that a detraining period could affect successful missions (aerobic performance deterioration), as well as promote a muscle imbalance between the legs, which could encourage muscle injuries and endanger combat missions.

Abstract Swimmer athletes showed a decreased ventilatory response and reduced sympathetic activation during peripheral hypoxic chemoreflex stimulation. Based on these observations, we hypothesized that swimmers develop a diminished cardiorespiratory coupling due to their decreased hypoxic peripheral response. To resolve this hypothesis, we conducted a study using coherence time‐varying analysis to assess the cardiorespiratory coupling in swimmer athletes. We recruited 12 trained swimmers and 12 control subjects for our research. We employed wavelet time‐varying spectral coherence analysis to examine the relationship between the respiratory frequency (Rf) and the heart rate (HR) time series during normoxia and acute chemoreflex activation induced by five consecutive inhalations of 100% N2. Comparing swimmers to control subjects, we observed a significant reduction in the hypoxic ventilatory responses to N2 in swimmers (0.012 ± 0.001 vs. 0.015 ± 0.001 ΔVE/ΔVO2, and 0.365 ± 0.266 vs. 1.430 ± 0.961 ΔVE/ΔVCO2/ΔSpO2, both p

Existe información limitada respecto a la respuesta de la frecuencia cardiaca (FC) a partir de fórmulas predictivas y prueba de ejercicio real entre adultos con hipertensión arterial (HTA) y normotensos, así como sobre las similitudes o diferencias vasculares entre muestras de diferente control de la presión arterial. El objetivo de este estudio fue describir y comparar la frecuencia cardiaca durante el ejercicio entre adultos con HTN y normotensos, así como describir parámetros de función endotelial y vasculares. Se realizó un estudio clínico descriptivo con 64 adultos (hombres y mujeres) que fueron divididos en tres grupos: hipertensión arterial (HTN n=26), presión arterial elevada (Ele n=16), o normotensos control (CG n=22). Los participantes se sometieron a una prueba de ejercicio, en la que se midió la FC (variable principal) y parámetros vasculares secundarios (clasificación percentil de la velocidad de la onda del pulso (%ILEPWVba), grosor máximo de la íntima-media carotídea (cIMTmax) y edad arterial entre otras. En la etapa 2 del test (50-100 vatios), el grupo HTN mostró una FC significativamente mayor vs. el grupo GC (+14 latidos/min), y vs. el grupo Ele (+15 latidos/min), ambos p

Unique worldwide, nitrate/iodine deposits (NIDs) are located along a 700 km geological belt in the Atacama Desert, Chile. They serve as the primary source of mineral ores for the extraction of iodine, sodium, and potassium nitrates. NIDs have been relatively underexplored from a biological perspective. To address this, we collected sixteen soil samples from abandoned mines in Oficinas Pissis and Savona for chemical, mineralogical, and metagenomic analyses. The soils primarily consisted of halite and darapskite, with only one sample being predominantly composed of thenardite. Deliquescence and water activity measurements yielded values ranging from 0.02% to 0.40% and 0.47 to 0.62, respectively. To investigate the presence, identification, relative abundance, and diversity of microbial life in NID soils, we employed MiSeq high-throughput sequencing and bioinformatic tools. The dominant phyla observed were Firmicutes and Proteobacteria, with Actinobacteria and Cyanobacteria being predominant in two soil samples. Furthermore, we detected nitrate/perchlorate-reducing bacterial activity in enriched cultures from the soil samples. This study sheds light on the resilience of microbial life in the Atacama Desert NIDs, providing compelling evidence for its existence and offering insight into factors that could facilitate it within this unique environment.

Preclinical research has provided compelling evidence indicating that exposure to hypobaric hypoxia (HH) results in a deterioration of spermatogenesis. This adverse effect extends to the underlying molecular mechanisms, progressively leading to impairments in the seminiferous epithelium and germ cells and alterations in semen parameters. Indeed, several studies have demonstrated that animals exposed to HH, whether in natural high-altitude environments or under simulated hypoxic conditions, exhibit damage to the self-renewal and differentiation of spermatogenesis, an increase in germline cell apoptosis, and structural alterations in the seminiferous tubules. One of the primary mechanisms associated with the inhibition of differentiation and an increase in apoptosis among germ cells is an elevated level of oxidative stress, which has been closely associated with HH exposure. Human studies have shown that individuals exposed to HH, such as mountaineers and alpinists, exhibit decreased sperm count, reduced motility, diminished viability, and increased sperm with abnormal morphology in their semen. This evidence strongly suggests that exposure to HH may be considered a significant risk factor that could elevate the prevalence of male infertility. This literature review aims to provide a comprehensive description and propose potential mechanisms that could elucidate the infertility processes induced by HH. By doing so, it contributes to expanding our understanding of the challenges posed by extreme environments on human physiology, opening new avenues for research in this field.