Repositorio Académico de la Universidad Católica del Maule
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Morphoanatomical evidence for functional incomplete dioecy in Cabralea canjerana subsp. polytricha (Meliaceae)
No full textDioecy is a sexual system characterized by the complete separation of male and female floral functions between individuals of the same species. Some species of the Meliaceae family are considered functionally dioecious because of the lack of noticeable morphological differences between their male and female flowers. Here, we performed morphological and anatomical studies of the flower of Cabralea canjerana subsp. polytricha to identify sexual dimorphism between its male and female flowers. We also examined aspects of floral and pollination biology that may be related to the sexual system of this subspecies. The field studies were carried out in two Brazilian Cerrado reserves. Cabralea canjerana subsp. polytricha presents similar female and male flowers that open between late afternoon and early evening and are visited by moths in the evening and small bees during the daytime. Floral biology dynamics indicate that moths are the primary pollinators. The similarity between male and female flowers may facilitate flower recognition by the visitors, enhancing pollen flow between morphs. However, compared with female plants, male plants have longer inflorescences and more flowers with larger anthers, which may attract more pollinators and disperse a higher number of pollen grains to the stigma of female flowers. Male flower carpels have ovules smaller than the female flowers. Most female flowers presented ovules with structurally normal embryo sacs. Male flowers may occasionally have normal ovules and produce fruits, which indicates that dioecy may not be complete, probably due to the functional aspect of its sexual system
Impact on body composition and physical fitness of an exercise program based on immersive virtual reality: a case report
No full textBackground/Objectives: The practice of physical activity contributes to obtaining adequate values of body composition and physical fitness, which is beneficial for people’s health. However, a large part of the adult population does not comply with the recommendations for physical activity, due to factors such as lack of time and nearby sports venues. Immersive virtual reality is a tool that allows individuals to immerse themselves in a simulated world and perceive visual, auditory, and tactile sensations. Its use in physical activity interventions favors exercise in situations that, due to time and space, could be limited in real life. The objective of this case report is to measure the impact on body composition and physical fitness of an exercise program executed through immersive virtual reality. Methods: The design is a case study with a quantitative approach developed through a physical activity intervention with immersive virtual reality in which body composition was evaluated considering fat and muscle components, and physical fitness considering cardiorespiratory fitness, speed-agility, and hand grip strength, through pre- and post-testing. The physical exercise program based on immersive virtual reality lasted 8 weeks. The subject of the study was a 24-year-old man, a second-year student of Pedagogy in Physical Education at a Chilean university, with no previous experience in this virtual tool. Results: The results indicate that for body composition the study subject decreased the fat component and slightly improved the musculature, while for physical fitness cardiorespiratory fitness and speed-agility improved, but manual grip strength decreased. Conclusions: It is concluded that the training developed through immersive virtual reality proves to be a tool that can promote improvements in body composition and physical fitness; it is necessary to carry out more research to validate the potential of this instrument as a means of contributing to the health of the population
A review of neural networks for metagenomic binning
No full textOne of the main goals of metagenomic studies is to describe the taxonomic diversity of microbial communities. A crucial step in metagenomic analysis is metagenomic binning, which involves the (supervised) classification or (unsupervised) clustering of metagenomic sequences. Various machine learning models have been applied to address this task. In this review, the contributions of artificial neural networks (ANN) in the context of metagenomic binning are detailed, addressing both supervised, unsupervised, and semi-supervised approaches. 34 ANN-based binning tools are systematically compared, detailing their architectures, input features, datasets, advantages, disadvantages, and other relevant aspects. The findings reveal that deep learning approaches, such as convolutional neural networks and autoencoders, achieve higher accuracy and scalability than traditional methods. Gaps in benchmarking practices are highlighted, and future directions are proposed, including standardized datasets and optimization of architectures, for third-generation sequencing. This review provides support to researchers in identifying trends and selecting suitable tools for the metagenomic binning problem
Effects of different postures on the hemodynamics and cardiovascular autonomic control responses to exercise in postural orthostatic tachycardia syndrome
No full textPurpose
To assess the effects of two different body positions on the cardiovascular autonomic profile during a single bout of exercise in patients with postural orthostatic tachycardia syndrome (POTS).
Methods
Thirteen patients with POTS and thirteen healthy controls (C) participated in the study. ECG, respiration, beat-by-beat arterial pressure and O2 consumption (VO2) were continuously recorded while on a cycle ergometer in supine and upright positions, before and during exercise (6 min, 50 Watts). Spectral analysis of RR intervals and systolic arterial pressure (SAP) variability provided indexes of cardiac sympathovagal interaction (LF/HF ratio), cardiac vagal modulation (HFRR, high-frequency component of RR variability, ~ 0.25 Hz), sympathetic vasomotor control (LFSAP, low-frequency component of SAP variability, 0.1 Hz) and baroreflex sensitivity (BRS, αLF).
Results
While supine, patients with POTS showed lower HFRR and αLF, greater heart rate (HR), LF/HF and LFSAP, compared with C, suggesting cardiovascular sympathetic over-activity and reduced BRS. While sitting upright, POTS showed greater HR and reduced HFRR and αLF compared with C. During supine exercise, SAP, HR, LF/HF increased and HFRR and αLF decreased similarly in POTS and C. In POTS, upright sitting exercise was associated with slightly higher vo2 , a greater increase in HR whereas LFSAP was lower than in C.
Conclusion
Upright exercise was associated with excessive enhancement of HR and a blunted increase of the sympathetic vasomotor control in POTS. Conversely, supine exercise-induced hemodynamic and autonomic changes similar in POTS and C, thus making supine exercise potentially more suitable for physical rehabilitation in POTS
Conical waveguide design for propagating light to a single fiber and its indoor characterization methodology
No full textThis study introduces a novel optical setup and methodology to increase the effective area of a multimode optical fiber (MMF) using a low-cost, 3D-printed conical waveguide (CW). Designed to simplify solar collection systems with Fresnel lenses (FL) and optical fibers, the setup efficiently couples light into a single silica MMF. For this, an indoor characterization method assesses transmission efficiency, verifying in advance its suitability for outdoor use while minimizing sun exposure risks for the people conducting the experiments. A laser flashlight provides a collimated light source with approximately 2° divergence for experiments. Geometric analysis and ray-tracing simulations validate the CW design, highlighting the importance of a low FL numerical aperture (NA). By reducing the FL's NA to 0.11 using masks, a maximum CW's transmittance of 34.7% and a net system efficiency of 17% are achieved. Key advantages include simplified assembly, avoiding the complexities of fiber bundle manufacturing, low optical attenuation over tens of meters, and safe indoor characterization. This approach presents a solution for compact photonic energy transport systems and provides a reference framework for identifying improvements to the collection system. The findings of this study are intended for use in a sunlight collector device for indoor lighting
Rational design, synthesis, and evaluation of novel polypharmacological compounds targeting NaV1.5, KV1.5, and K2P channels for atrial fibrillation
No full textAtrial fibrillation (AF) involves electrical remodeling of the atria, with ion channels such as NaV1.5, KV1.5, and TASK-1 playing crucial roles. This study investigates acetamide-based compounds designed as multi-target inhibitors of these ion channels to address AF. Compound 6f emerged as the most potent in the series, demonstrating a strong inhibition of TASK-1 (IC50 ∼ 0.3 μM), a moderate inhibition of NaV1.5 (IC50 ∼ 21.2 μM) and a subtle inhibition of KV1.5 (IC50 ∼ 81.5 μM), alongside unexpected activation of TASK-4 (∼ 40% at 100 μM). Functional assays on human atrial cardiomyocytes from sinus rhythm (SR) and patients with AF revealed that 6f reduced action potential amplitude in SR (indicating NaV1.5 block), while in AF it increased action potential duration (APD), reflecting high affinity for TASK-1. Additionally, 6f caused hyperpolarization of the resting membrane potential in AF cardiomyocytes, consistent with the observed TASK-4 activation. Mathematical modeling further validated its efficacy in reducing AF burden. Pharmacokinetic analyses suggest favorable absorption and low toxicity. These findings identify 6f as a promising multi-target therapeutic candidate for AF management
High temperature induces oxidative damage, immune modulation, and atrophy in the gills and skeletal muscle of the teleost fish black cusk-eel (Genypterus maculatus)
No full textThe high temperature associated with heat waves is a relevant abiotic factor that could impact the biology of teleost fish. The innate immune response, muscular growth, and oxidative stress status are relevant functions in fish tissues that could be affected by increased temperature. In this study, black cusk-eel (Genypterus maculatus) juveniles were subjected to increased temperature, to experimentally replicate heat waves registered from the South Pacific Ocean for five days. The results showed that thermal stress modulated the immune response in gills, with up-regulation of antibacterial peptides, pro-inflammatory cytokines, and Toll-like receptors genes, including hepcidin, gzma, tnfa, cxcl8, and tlr5, with no effect on complement system genes. In skeletal muscle, high temperature triggered atrophy-related gene expression, with up-regulation of foxo1, foxo3, fbxo32, murf1, and atg16l. Increased temperature also generated an up-regulation of transcripts encoding heat shock protein (hsp60 and hsp70) in gills and skeletal muscle, generating oxidative stress in both tissues, with increased expression of the antioxidant genes sod1 and gpx1 in gills and skeletal muscle, respectively, with oxidative damage observed at the DNA level (AP sites), protein (carbonyl content), and lipoperoxidation (HNE content) in both tissues. The present study shows that short-term increases in temperature like those observed in heat waves could affect the immune response in gills, induced atrophy in skeletal muscle, and generate oxidative stress in a teleost species important for Chilean aquaculture diversification, information relevant under the context of climate change scenario
SGD3 - Health and wellness: mother and father perspectives on healthy eating in Chile
No full textObjective: The aim of this research is to analyze the food preferences of fathers and mothers in the Maule region. In this context, we explore statistical differences that can inform the development of business and institutional strategies, considering food consumption preferences.
Theoretical Framework: Consumer preferences play a vital role in the development of plans and programs that promote a high quality of life. Both public and private organizations should advocate for food as a fundamental right within society by strategically managing the tastes and preferences associated with food products.
Method: A self-evaluation instrument was administered to a convenience sample of 120 parents in the Maule region of Chile. Descriptive statistics and measures of central tendency were calculated, followed by a reliability analysis for each dimension. Finally, statistical differences were examined.
Results and Discussion: Significant differences are found in various aspects, including food purchase criteria, the reading of nutrition labels, the evaluation of “High in” seals on packaged products, and the perception of the importance of food attributes. Additionally, certain preferences emerged as noteworthy based on the assessments provided by parents in the Maule region.
Implications of the research: This research provides information that can be used for the design of strategies concerning the preferences of fathers and mothers according to the food purchase decision. In terms of its theoretical value, the findings allow us to affirm that food preferences are different according to the particularities of the research subjects. As for its social value, the results can be used for the design of public policies that contribute to the social welfare of the social fabric.
Originality/Value: It is evident the havoc being caused in society by excesses and an unbalanced life. In this sense, this research provides inputs for the design and strategic management that encourage healthy eating as a basis for social welfare in the Maule region
Taxonomic and predicted functional profiling of coexisting rhizosphere microbiomes of Deschampsia antarctica and Colobanthus quitensis along an altitudinal transect in Admiralty Bay, Maritime Antarctica
No full textPurpose
The Antarctic Peninsula represents a unique ecosystem characterized by extremely harsh environmental conditions. In this study, we investigated the microbial diversity and functionality of Antarctic soils, focusing on the coexisting rhizosphere microbiomes associated with the only two native vascular plant species, Deschampsia antarctica and Colobanthus quitensis.
Methods
Soil samples were collected from three sites along an altitudinal transect near Admiralty Bay on King George Island, Antarctic Peninsula. Comprehensive chemical analyses of the soils were performed, followed by DNA extraction and bioinformatic analyses to explore microbial diversity and metabolic functions.
Results
Our results revealed significant disparities in soil chemical composition across sites, with distinct variations observed in pH, calcium, magnesium, aluminum saturation, cation exchange capacity, and phosphorus concentrations. Despite these differences, taxonomic profiling via metabarcoding indicated relatively homogeneous bacterial communities in terms of alpha diversity but significant differences in beta diversity among the sites. Firmicutes dominated at Site 1, while Proteobacteria predominated at Site 2, and Actinobacteriota at Site 3. Functional prediction analysis revealed diverse metabolic activities within Antarctic soil microbial communities, with heightened fermentation potential in Sites 1 and 2, and notable functions related to aromatic compound degradation and phototrophy in Site 3.
Conclusions
These findings contribute to our understanding of the intricate dynamics of Antarctic soil microbiomes, highlighting the influence of soil physicochemical properties and plant-microbe interactions on microbial community structures and functions in these extreme environments. Such insights have substantial implications for conservation strategies and the advancement of biotechnological applications in Antarctic ecosystems
Assessing cultivar-specific susceptibility and morphological adaptations of Bactrocera oleae (Diptera: Tephritidae) in olive orchards
No full textThe olive fruit fly, Bactrocera oleae (Rossi), is the most important widespread pest in olive-growing areas worldwide, causing significant yield losses and deterioration of olive oil quality. This study hypothesized that olive cultivars differ in their susceptibility to B.oleae and that the cultivar in which the pest develops may affect population variability. The primary goal was to assess susceptibility across 6 olive cultivars, while the secondary goal was to analyze population variability using geometric morphometrics to identify cultivar-specific phenotypic differences. Conducted at 2 sites, Banjevci (Dalmatia) and Vodnjan (Istria), the study revealed significant differences in infestation levels, emergence, and wing morphology. Higher humidity in Vodnjan favored increased fly populations. Larger-fruited cultivars such as Oblica, Istarska bjelica, and Ascolana tenera experienced higher infestation rates, whereas smaller-fruited cultivars like Frantoio and Leccino exhibited lower infestation levels. Wing shape analysis highlighted sexual dimorphism, with female flies exhibiting broader wings that may enhance dispersal and oviposition efficiency, particularly in larger fruits. The observed phenotypic plasticity of B. oleae across cultivars and locations indicates an ability to adapt to varied host and cultivation conditions, enhancing pest resilience. The findings underscore the role of cultivar selection as a passive pest management strategy and demonstrate the utility of geometric morphometrics in capturing cultivar-specific morphological adaptations