Search Results (20)

In this paper, the electrochemical performance of the NiAl intermetallic immersed in the 60% NaNO₃-40% KNO₃ (wt%) eutectic mixture, also known as Solar Salt, is reported. Mass loss measurements and electrochemical tests evaluate its behavior at different temperatures (300, 400, and 500 °C). Mass loss measurements are performed over 1000 h, and electrochemical tests over 100 h. The mass loss results show that the Ni₃Al intermetallic exhibits excellent corrosion resistance under the test conditions. Electrochemical measurements confirm the excellent performance of the Ni₃Al intermetallic in molten solar salt in the test temperature range. Experimental observations show that increasing temperature decreases the corrosion resistance of the intermetallic and favors the formation of protective layers of the Al₂O₃ and NaAlO₂ types. Full article

There is a need to evaluate Sentinel-2 (S2) fire severity spectral indices (SFSIs) for predicting vegetation and soil burn severity for a variety of ecosystems. We evaluated the performance of 26 SFSIs across three fires in seasonally dry oak–pine forests in central-western Mexico. The SFSIs were derived from composites of S2 multispectral images obtained with Google Earth Engine (GEE), processed using different techniques, for periods of 30, 60 and 90 days. Field verification was conducted through stratified random sampling by severity class on 100 circular plots of 707 m², where immediate post-fire effects were evaluated for five strata, including the canopy scorch in overstory (OCS)—divided in canopy (CCS) and subcanopy (SCS)—understory (UCS) and soil burn severity (SBS). Best fits were obtained with relative, phenologically corrected indices of 60–90 days. For canopy scorch percentage prediction, the indices RBR3c and RBR5n, using NIR (bands 8 and 8a) and SWIR (band 12), provided the best accuracy (R² = 0.82). SBS could be best mapped from RBR1c (using 11 and 12 bands) with relatively acceptable precision (R² = 0.62). Our results support the feasibility to separately map OCS and SBS from S2, in relatively open oak–pine seasonally dry forests, potentially supporting post-fire management planning. Full article

Introduction: Malnutrition is a critical issue among cancer patients, leading to adverse clinical outcomes, including increased treatment toxicity, reduced physical function, and decreased survival. Nutritional screening is essential to identify patients at risk and provide timely interventions. Objectives: This study aimed to assess the effectiveness of various nutritional screening tools in identifying the risk of malnutrition and obesity in Mexican cancer outpatients. Methods: A cross-sectional study was conducted with 396 adult cancer outpatients at a public hospital in Mexico. Nutritional risk was evaluated using NRS-2002, MUST, MST, NUTRISCORE, and PG-SGA, while malnutrition was assessed using GLIM criteria and PG-SGA. Anthropometric and demographic data were collected. Sensitivity, specificity, and kappa coefficients were calculated to determine the performance of the screening tools. Results: Nutritional risk was identified in 22.7–26.5% of patients, with the highest agreement observed between MUST and PG-SGA (k = 0.64). Malnutrition prevalence was higher using GLIM criteria (37.4%) compared to PG-SGA (25.8%, p < 0.001). Overweight and obesity affected 37.1% and 23.5% of patients, respectively. Low BMI and reduced HGS were strongly associated with nutritional risk and malnutrition (p < 0.001). Conclusions: MUST and PG-SGA are reliable tools for nutritional screening in cancer outpatients, while GLIM criteria detect a higher prevalence of malnutrition than PG-SGA. The high rates of overweight and obesity highlight the complex nutritional challenges in this population, emphasizing the need for tailored nutritional assessments and interventions. Full article

The skin of fish is a physicochemical barrier that is characterized by being formed by cells that secrete molecules responsible for the first defense against pathogenic organisms. In this study, the biological activity of peptides from mucus of Seriola lalandi and Seriolella violacea were identified and characterized. To this purpose, peptide extraction was carried out from epidermal mucus samples of juveniles of both species, using chromatographic strategies for purification. Then, the peptide extracts were characterized to obtain the amino acid sequence by mass spectrometry. Using bioinformatics tools for predicting antimicrobial and antioxidant activity, 12 peptides were selected that were chemically produced by simultaneous synthesis using the Fmoc-Tbu strategy. The results revealed that the synthetic peptides presented a random coil or extended secondary structure. The analysis of antimicrobial activity allowed it to be discriminated that four peptides, named by their synthesis code 5065, 5069, 5070, and 5076, had the ability to inhibit the growth of Vibrio anguillarum and affected the copepodite stage of C. rogercresseyi. On the other hand, peptides 5066, 5067, 5070, and 5077 had the highest antioxidant capacity. Finally, peptides 5067, 5069, 5070, and 5076 were the most effective for inducing respiratory burst in fish leukocytes. The analysis of association between composition and biological function revealed that the antimicrobial activity depended on the presence of basic and aromatic amino acids, while the presence of cysteine residues increased the antioxidant activity of the peptides. Additionally, it was observed that those peptides that presented the highest antimicrobial capacity were those that also stimulated respiratory burst in leukocytes. This is the first work that demonstrates the presence of functional peptides in the epidermal mucus of Chilean marine fish, which provide different biological properties when the fish face opportunistic pathogens. Full article

According to the available ethnobotanical data, the Bouvardia ternifolia plant has long been used in Mexican traditional medicine to relieve the symptoms of inflammation. In the present study, the cytotoxic effect of extracts obtained from the flowers, leaves and stems of B. ternifolia using hexane, ethyl acetate (AcOEt) and methanol (MeOH) was evaluated by applying them to the SiHa and MDA-MB-231 cancer cell lines. An MTT reduction assay was carried out along with = biological activity assessments, and the content of total phenols, tannins, anthocyanins, betalains and saponins was quantified. According to the obtained results, nine extracts exhibited a cytotoxic effect against both the SiHa and MDA lines. The highest cytotoxicity was measured for leaves treated with the AcOEt (ID₅₀ of 75 µg/mL was obtained for MDA and 58.75 µg/mL for SiHa) as well as inhibition on ABTS•⁺ against DPPH• radical, while MeOH treatment of stems and AcOEt of flowers yielded the most significant antioxidant capacity (90.29% and 90.11% ABTS•⁺ radical trapping). Moreover, the highest phenolic compound content was measured in the stems (134.971 ± 0.294 mg EAG/g), while tannins were more abundant in the leaves (257.646 mg eq cat/g) and saponins were most prevalent in the flowers (20 ± 0 HU/mg). Screening tests indicated the presence of flavonoids, steroids, terpenes and coumarins, as well as ursolic acid, in all the studied extracts. These results demonstrate the biological potential of B. ternifolia. Full article

Background: The elderly admitted to nursing homes have especially suffered the havoc of the COVID-19 pandemic since most of them are not prepared to face such health problems. Methods: An innovative coordinated on-site medicalization program (MP) in response to a sizeable COVID-19 outbreak in three consecutive waves was deployed, sharing coordination and resources among primary care, the referral hospital, and the eleven residences. The objectives were providing the best possible medical care to residents in their environment, avoiding dehumanization and loneliness of hospital admission, and reducing the saturation of hospitals and the risk of spreading the infection. The main outcomes were a composite endpoint of survival or optimal palliative care (SOPC), survival, and referral to the hospital. Results: 587 of 1199 (49%) residents were infected, of whom 123 (21%) died. Patients diagnosed before the start of the MP presented SOPC, survival, and referrals to the hospital of 83%, 74%, and 22.4%, opposite to 96%, 84%, and 10.6% of patients diagnosed while the MP was set up. The SOPC was independently associated with an MP (OR 3.4 [1.6–7.2]). Conclusion: During the COVID-19 outbreak, a coordinated MP successfully obtained a better rate of SOPC while simultaneously reducing the need for hospital admissions, combining optimal medical management with a more compassionate and humanistic approach in older people. Full article

Seizure-mediated oxidative stress is a crucial mechanism in the pathophysiology of epilepsy. This study evaluated the antioxidant effects of daytime-restricted feeding (DRF) and the role of the Nrf2 signaling pathway in a lithium-pilocarpine model seizure model that induces status epilepticus (SE). We performed a lipoperoxidation assay and dihydroethidium fluorescence to measure oxidative stress markers in the hippocampus (malondialdehyde and reactive oxygen species). The protein content of Nrf2 and its downstream protein SOD2 was evaluated using Western blotting. The cellular distribution of the Nrf2 and SOD2 proteins in the pyramidal cell layer of both the CA1 and CA3 hippocampal subfields and astrocytes (GFAP marker) were quantified using immunofluorescence and immunohistochemistry, respectively. Our results indicate that DRF reduced the malondialdehyde levels and the production of reactive oxygen species. Furthermore, a significant increase in Nrf2 and SOD2 protein content was observed in animals subjected to restrictive diet. In addition, DRF increased the relative intensity of the Nrf2 fluorescence in the perinuclear and nuclear compartments of pyramidal neurons in the CA1 subfield. Nrf2 immunoreactivity and the astrocyte marker GFAP also increased their colocalization under DRF conditions. Additionally, SOD2 immunoreactivity was increased in CA1 pyramidal neurons but not in the CA3 region. Our findings suggest that DRF partially prevents oxidative stress by increasing the Nrf2 transcriptional factor and the SOD2 enzyme during the development of SE. Full article

In the current study, the concatenation model of birefringent fibers is explored for the first time, and we present optical soliton solutions to the model. The integration algorithm used to achieve this retrieval is the method of undetermined coefficients, which yields a wide range of soliton solutions. The parameter constraints arise naturally during the derivation of the soliton solutions, which are essential for such solitons to exist. Full article

This paper retrieves an optical 1–soliton solution to a model that is written as a concatenation of the Lakshmanan–Porsezian–Daniel model and Sasa–Satsuma equation. The method of undetermined coefficients obtains a full spectrum of 1–soliton solutions. The multiplier approach yields the conserved densities, which subsequently lead to the conserved quantities from the bright 1–soliton solution. Full article

This is an observational cross-sectional study designed to ascertain the prevalence and severity of dysexecutive symptoms in high school students during the COVID-19 pandemic. The validated Spanish version of the Dysexecutive Questionnaire (DEX) was used. A total of 2396 participants aged 14–22 years were included. Our sample yielded a mean DEX scale score of 28.14 ± 17.42. By the DEX classification, 889 (37.1%) students achieved optimal scores, 384 (16%) reported mild dysexecutive symptoms, 316 (13.2%) reported moderate dysexecutive symptoms, and 807 (33.7%) reported strong dysexecutive symptoms. We found a significant difference between those with and those without employed mothers, with the former scoring higher (p = 0.004), the same as those with both parents employed (p = 0.004). Adolescents face emotional susceptibility and changes in their family, social, and educational environment related to isolation, resulting in altered emotional responses and social interaction. Full article

Seed uniformity and stability testing, and multiplication, are key steps in the seed supply chain of the common bean (Phaseolus vulgaris L.) and other crops. Optimizing agronomical practices in these phases can ultimately ensure seed quality and availability, and germplasm prospective utilization. However, farmers have rarely standardized seed testing and propagation protocols in local common bean landraces conserved in situ. An example of this is the Liborino variety (var.), a promising yellow Andean common bean known for its presumably high digestibility and adaptation to the local conditions of the Cauca river canyon (northwest Andes of Colombia), but likely experiencing genetic erosion after decades of suboptimal propagation. Therefore, this work intended to evaluate and select locally adapted genotypes of common bean var. Liborino for commercial use, to be later multiplied, evaluated by participatory breeding, and eventually shared with farmers. Specifically, we evaluated 44 accessions of var. Liborino common bean in six adaption and yield field trials in the Cauca river canyon at 1100 and 1400 m a.s.l, and in AGROSAVIA’s “La Selva” research station at 2100 m a.s.l. In parallel, we carried out standardized seed multiplication of a Liborino genotype using best practices to guarantee uniformity and stability. From the 44 accessions, nine were well adapted to the tested local conditions. Four of these accessions exhibited a bush type growth habit, while the remaining five were climbers. The trials revealed maximum average extrapolated yields of up to 1169.4 ± 228.4 kg ha⁻¹ for the bush types (G8152) and up to 1720.0 ± 588.4 kg ha⁻¹ for the climbers (G51018), both at 2100 m a.s.l. Three climbing accessions matched farmers’ expectations for seed coat color and shape, according to a participatory selection exercise. Uniform and stable seed of the selected genotype was delivered in 2022 to 39 farmers, ~6.5 kg of seeds per farmer. Our results will allow implementing bean genetic improvement pipelines, promoting var. Liborino commercialization, and boosting the economic and sustainable development of the rural communities in the Cauca river canyon. Seed uniformity testing and multiplication pipelines must be extended to other bean landraces conserved in situ. Full article

Some plants have great resistance against herbivores, invertebrates, insects, bacteria, and fungi. This resistance is mostly present in plants containing alkaloids, which are the substances responsible for giving them defensive properties. The genus Datura contains tropane alkaloids and all plants from this genus have defensive properties. In this work, we report the toxic effect against fungi of Datura stramonium extracts, obtained by the Petri dish method. The extraction solvents were water, ethanol, 2-propanol, n-butanol, propanone, butanone, 3-methyl-2-pentanone, dichloromethane, xylene, and toluene. The test fungi were Trametes versicolor (L. ex. Fr) Pilát and Rhodonia placenta (Fr.) Niemelä, K.H.Larss. & Schigel. It was found that water, butanone, and toluene extracts promoted mycelial growth, xylene extracts neither inhibited nor promoted mycelial growth, while the other extracts slightly inhibited the growth of these fungi. Full article

Bipolar disorder (BD) is a multifactorial chronic psychiatric disease highly defined by genetic, clinical, environmental and social risk factors. The present systematic review and meta-analysis aimed to examine the relationship between inflammatory and neurotrophic factors and clinical, social and environmental factors involved in the development and the characterization of BD. Web of Science, PubMed, PsycINFO, Scopus and Science Direct were searched by two independent reviewers. The systematic review was registered in PROSPERO (CRD42020180626). A total of 51 studies with 4547 patients with a diagnosis of BD were selected for systematic review. Among them, 18 articles were included for meta-analysis. The study found some evidence of associations between BDNF and/or inflammatory factors and different stressors and functional and cognitive impairment, but limitations prevented firm conclusions. The main finding of the meta-analysis was a negative correlation between circulating levels of BDNF and depression severity score (standardized mean difference = −0.22, Confidence Interval 95% = −0.38, −0.05, p = 0.01). Evidence indicates that BDNF has a role in the depressive component of BD. However, the poor consistency found for other inflammatory mediators clearly indicates that highly controlled studies are needed to identity precise biomarkers of this disorder. Full article

Using both analytical and numerical techniques, we discuss wave solutions within the framework of an extended nonlinear Schrödinger equation with constant coefficients equipped with spatiotemporal dispersion, self-steepening effects, and a Raman scattering term. We present the exact traveling wave solution of the system in terms of Jacobi elliptic functions and mention some symmetry results as they relate to the resulting ordinary differential equation. A constructed bright soliton solution serves as the base to compare a numerical solution of the system using spectral Fourier methods with a precise statistical low-rank approximation using a data-driven approach aided by the Koopman operator theory. We found that the spatiotemporal feature added to the model serves as a regularizing tool that enables a precise reconstruction of the original solution. Full article

Chronic and non-healing wounds demand personalized and more effective therapies for treating complications and improving patient compliance. Concerning that, this work aims to develop a suitable chitosan-based thermo-responsive scaffold to provide 24 h controlled release of Dexketoprofen trometamol (DKT). Three formulation prototypes were developed using chitosan (F1), 2:1 chitosan: PVA (F2), and 1:1 chitosan:gelatin (F3). Compatibility tests were done by DSC, TG, and FT-IR. SEM was employed to examine the morphology of the surface and inner layers from the scaffolds. In vitro release studies were performed at 32 °C and 38 °C, and the profiles were later adjusted to different kinetic models for the best formulation. F3 showed the most controlled release of DKT at 32 °C for 24 h (77.75 ± 2.72%) and reduced the burst release in the initial 6 h (40.18 ± 1.00%). The formulation exhibited a lower critical solution temperature (LCST) at 34.96 °C, and due to this phase transition, an increased release was observed at 38 °C (88.52 ± 2.07% at 12 h). The release profile for this formulation fits with Hixson–Crowell and Korsmeyer–Peppas kinetic models at both temperatures. Therefore, the developed scaffold for DKT delivery performs adequate controlled release, thereby; it can potentially overcome adherence issues and complications in wound healing applications. Full article