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Biocultural correlates of gross motor coordination in prepubescent children: A cross-sectional study
No full textAim: This study aimed to explore the association of gross motor coordination (GMC) with a matrix of biocultural factors in prepubescent children, taking into account weight status, somatic maturation, sociodemographic variables, and type of school. Methods: One hundred twenty-nine prepubescent children, of both sexes, aged between 8.00 and 8.99, were assessed for GMC (Körperkoordinationstest Für Kinder - KTK), weight status, biological maturation (predicted mature stature), sex, mother's education level and type of school. Binary logistic regression was used to examine the relationship between higher values of KTK and associated biocultural factors. Results: Normoponderal children are more likely to attain better total KTK scores than those with overweight or obesity (OR: 2.942; LC 95%: 1.189, 7.280). In addition, children who are more advanced in terms of biological maturation exhibited significantly lower odds of being in the high KTK category than their less advanced peers (OR: 0.670; LC 95%: 0.474,0.946). Sex, mother's education level and the type of school are not associated with higher performance on KTK. Conclusion: Weight status and biological maturation are associated with motor competence in prepubescent children. Future studies should consider additional correlates to better understand the complex interactions between biological, psychosocial and behavioral factors in the prediction of motor competence. © 2023 Wiley Periodicals LLC
Energy Consumption in Higher Education Institutions: A Bibliometric Analysis Focused on Scientific Trends
No full textWhile universities are expected to exemplify sustainable practices, they often encounter high energy demands. This dichotomy highlights the necessity for research into their energy consumption. Through a Systematic Literature Review, we examined international research trends in this field and explored factors influencing energy consumption. The importance of this article stems from its novel approach to energy consumption in universities, addressed from a global and comprehensive perspective, offering generalizable insights. Additionally, it pioneers in the use of a market concentration indicator (Herfindahl–Hirschman index) to measure the level of diversity in various bibliometric aspects. The extended perspective of our approach helps to close knowledge gaps about scientific trends and common energy consumption factors. Our results show that this topic has been investigated with limited involvement of social sciences. Building function, research intensity, and disciplinary orientation are distinctive factors in energy consumption in this field. Most influential authors, countries, and journals in this area were identified. This analysis contributes academically, by mapping research trends and providing guidance for future studies; practically, by offering insights for educational administrators on common factors affecting energy consumption; and in terms of policy, by advocating for the promotion of social sciences-based investigations on the topic. © 2024 by the authors.Andalusian Regional Government, (SEJ-132); Cátedra de Economía de la Energía y del Medio Ambiente; Departamento de Análisis Económico y Economía Política; Red Eléctrica de España at the University of Seville; Universidad de SevillaUniversidad Autónoma de Chil
Electrophysiological Recordings of Oligodendroglia in Adult Mouse Brain Slices
No full textCommunication between neurons and oligodendrocyte lineage cells has attracted a great interest since multiple discoveries revealed its important roles in brain function under physiological and pathological conditions. Oligodendroglia responds to neuronal activity through the activation of a plethora of ion channels and receptors whose expression changes depending on the maturation state and whose characterization helps defining their interactions with neurons. Here, we describe in detail the methodology for carrying out electrophysiological patch-clamp recordings of oligodendroglial cells in acute brain slices of adult mice, with an emphasis on tailor-made solutions to make this experimental approach successfully. Additionally, we describe a protocol for combining photostimulation of neurons with patch-clamp recordings of oligodendroglia. © The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature 2024
Amino acids as bio-organocatalysts in ring-opening copolymerization for eco-friendly synthesis of biobased oligomers from vegetable oils
No full textHerein, we present an innovative synthetic approach for producing a diverse set of biobased oligomers. This method begins with olive oil and employs a wide variety of commercially available amino acids (AAs) as bio-organocatalysts, in addition to tetrabutylammonium iodide (TBAI) as a cocatalyst, to synthesize various biobased oligomers. These biobased oligomers were strategically prepared starting from epoxidized olive oil (EOO) and a variety of cyclic anhydrides (phthalic, PA; maleic, MA; succinic, SA; and glutaric, GA). Among the amino acids tested as bio-organocatalysts, l-glutamic acid (l-Glu) showed the best performance for the synthesis of both poly(EOO-co-PA) and poly(EOO-co-MA), exhibiting 100% conversion at 80 °C in 2 hours, whereas the formation of poly(EOO-co-SA) and poly(EOO-co-GA) required more extreme reaction conditions (72 hours under toluene reflux conditions). Likewise, we have succeeded in obtaining the trans isomer exclusively for the MA based-oligomer within the same synthetic framework. The obtained oligomers were extensively characterized using techniques including NMR, FT-IR, GPC and TGA. A series of computational simulations based on density functional theory (DFT) and post-Hartree Fock (post-HF) methods were performed to corroborate our experimental findings and to obtain an understanding of the reaction mechanisms. © 2024 The Royal Society of Chemistry.Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECYT, (3220023, 1220241, 11230124, FOVI230027); Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECY
Mitochondria-tau association promotes cognitive decline and hippocampal bioenergetic deficits during the aging
No full textCurrent studies indicate that pathological modifications of tau are associated with mitochondrial dysfunction, synaptic failure, and cognitive decline in neurological disorders and aging. We previously showed that caspase-3 cleaved tau, a relevant tau form in Alzheimer's disease (AD), affects mitochondrial bioenergetics, dynamics and synaptic plasticity by the opening of mitochondrial permeability transition pore (mPTP). Also, genetic ablation of tau promotes mitochondrial function boost and increased cognitive capacities in aging mice. However, the mechanisms and relevance of these alterations for the cognitive and mitochondrial abnormalities during aging, which is the primary risk factor for AD, has not been explored. Therefore, in this study we used aging C57BL/6 mice (2–15 and 28-month-old) to evaluate hippocampus-dependent cognitive performance and mitochondrial function. Behavioral tests revealed that aged mice (15 and 28-month-old) showed a reduced cognitive performance compared to young mice (2 month). Concomitantly, isolated hippocampal mitochondria of aged mice showed a significant decrease in bioenergetic-related functions including increases in reactive oxygen species (ROS), mitochondrial depolarization, ATP decreases, and calcium handling defects. Importantly, full-length and caspase-3 cleaved tau were preferentially present in mitochondrial fractions of 15 and 28-month-old mice. Also, aged mice (15 and 28-month-old) showed an increase in cyclophilin D (CypD), the principal regulator of mPTP opening, and a decrease in Opa-1 mitochondrial localization, indicating a possible defect in mitochondrial dynamics. Importantly, we corroborated these findings in immortalized cortical neurons expressing mitochondrial targeted full-length (GFP-T4-OMP25) and caspase-3 cleaved tau (GFP-T4C3-OMP25) which resulted in increased ROS levels and mitochondrial fragmentation, along with a decrease in Opa-1 protein expression. These results suggest that tau associates with mitochondria and this binding increases during aging. This connection may contribute to defects in mitochondrial bioenergetics and dynamics which later may conduce to cognitive decline present during aging. © 2024 Elsevier Inc.Agencia Nacional de Investigación y Desarrollo, ANID; Fondo de Ciencia y Tecnología; Universidad Autónoma de Coahuila, UAdeC; GVWJ; Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECYT, (1200178); Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECYT; National Institutes of Health, NIH, (AG073121, HL144776); National Institutes of Health, NI
Adsorption properties of M-UiO-66 (M = Zr(iv); Hf(iv) or Ce(iv)) with BDC or PDC linker
No full textThe increasing CO2 emissions and their direct impact on climate change due to the greenhouse effect are environmental issues that must be solved as soon as possible. Metal-organic frameworks (MOFs) are one class of crystalline adsorbent materials that are thought to have enormous potential in CO2 capture applications. In this research, the effect of changing the metal center between Zr(iv), Ce(iv), and Hf(iv), and the linker between BDC and PDC has been fully studied. Thus, the six UiO-66 isoreticular derivatives have been synthesized and characterized by FTIR, PXRD, TGA, and N2 adsorption. We also report the BET surface area, CO2 adsorption capacities, kinetics, and the adsorption isosteric heat (Qst) of the UiO-66 derivatives mentioned family. The CO2 adsorption kinetics were evaluated using pseudo-first order, pseudo-second order, Avrami's kinetic models, and the rate-limiting step with Boyd's film diffusion, interparticle diffusion, and intraparticle diffusion models. The isosteric heats of CO2 adsorption using various MOFs are in the range 20-65 kJ mol−1 observing differences in adsorption capacities between 1.15 and 4.72 mmol g−1 at different temperatures due to the electrostatic interactions between CO2 and extra-framework metal ions. The isosteric heat of adsorption calculation in this report, which accounts for the unexpectedly high heat released from Zr-UiO-66-PDC, is finally represented as an increase in the interaction of CO2 with the PDC linker and an increase in Qst with defects. © 2024 The Royal Society of Chemistry.Universidad Autónoma de Chil
Pterygoid Implants, A Treatment Option
No full textThe partially edentulous in the posterior maxilla bone is produced mainly by the loss of molars due to caries, periodontal disease and excessive force supported by the teeth of this sector. Dental implants greater than 10 mm, are rarely placed in this area due to a higher probability of failure for the low bone volume and bone quality poor. In the skull, in the post jawbone relationship, we find a pterygomaxillary buttress. This allows, in some situations, the rehabilitation of atrophic jaws by placing implants with a parasinusal angulation, avoiding surgical techniques or more complex procedure. The pterygoid implant is a possible treatment to rehabilitate the atrophic posterior maxilla, anchored in cortical bone of the pterygoid process. A case of placement of pterygoid implants in a woman 58 years old with a large pneumatization in both maxillary sinuses, with a remaining alveolar bone 1-2 mm is reported
Knowledge of Dental Students in Relation to Local Anesthetics and Associated Complications
No full textLocal anesthesia is the most frequently performed procedure for all dentists and, despite their possible complications, often aspects such as dosage, contraindications and systemic effects are neglected. The objectives of this study are to evaluate prospectively the knowledge of undergraduate students for the technical, dosage and indication of local anesthetics in daily dental practice, in addition to clinical observation of possible complications from anesthesia. Questionnaires were distributed to students asking about the procedure undertaken, anesthetic volume used, because of the choice of the anesthetic, anesthetic dosage calculation, habit of relating the patient's weight dosage with the dosage being applied, habit of observing the reflux in cartridge in the anesthetic infiltration act and adverse effects on patients, type of anesthetic technique performed and expected time to onset of action of the drug. At the end of this study, we intend to be a greater awareness of students (undergraduates) about the systemic effects of local anesthetics in patients, and possibly decrease the expenses of the institution with excessive use of anesthetic cartridges arising from incorrect anesthetic technique. The vast majority of undergraduate students have no knowledge about the type of anesthesia to be used, the amount to be administered and the anesthetic action time. The awareness of students about the dosage of anesthetics and their systemic problems, reduces waste and the cost of the institution by the indiscriminate use of anesthetics, therebycontributing to improve the clinical management of students at graduation
RELACIÓN ENTRE LA DEPENDENCIA DE LAS TRANSFERENCIAS INTERGUBERNAMENTALES Y LA INVERSIÓN FINANCIERA EN GESTIÓN DEL RIESGO DE DESASTRES A NIVEL MUNICIPAL EN COLOMBIA, 2012- 2015
No full textEn este trabajo se indaga sobre la relación causal entre la dependencia de las transferencias intergubernamentales y el desempeño en la inversión financiera a nivel municipal en gestión del riesgo de desastres en Colombia para el periodo 2012-2015, mediante el uso de un modelo de ecuaciones estructurales (SEM). Los resultados señalan que la dependencia de las transferencias, como indicador de las restricciones a la autonomía financiera, limita la disponibilidad de recursos de libre inversión a nivel municipal y restringe los incentivos para la responsabilidad local incidiendo negativamente en la inversión financiera en el tema. Con base en esta evidencia se discuten los vínculos entre descentralización y desempeño en gestión de riesgo para el caso colombiano.
 
Removal and photocatalytic degradation of methylene blue on ZrO2 thin films modified with Anderson-Polioxometalates (Cr3+, Co3+, Cu2+): An experimental and theoretical study
No full textIn this work, several ZrO2 thin films modified with Anderson-type polyoxomolybdates (POMs) with general formula (NH4)6-n[XMo6O24H6]-6+n where X = Co3+, Cr3+ and, Cu2+ were prepared. Thin films were characterized through SEM and EDX assay, UV–Vis diffuse reflectance and Fourier Transform Infrared (FTIR) assay. The optical bandgap of ZrO2 thin films was determined to be 3.25 eV, while the modified thin films showed a red shift in the optical activity compared with bare ZrO2 thin films. Methylene Blue (MB) adsorption studies showed that Freundlich isotherm describes properly the experimental data for modified-ZrO2 thin films. Besides, the kinetic results showed the MB adsorption of modified-ZrO2 thin films was superior to bare ZrO2 thin film. The adsorption rate values (K2) of the pseudo-second order model follow these trend ZrO2/CrPOM > ZrO2/CoPOM > ZrO2/CuPOM > ZrO2. The photocatalytic activity of the thin films for MB decomposition under UV and Visible irradiation was studied. Among all the catalysts, the ZrO2 thin films showed the lowest photocatalytic degradation rate kap value (kap = 1.5 × 10−3 min−1), while the best result was obtained for ZrO2/CrPOM thin films (kap = 5.7 × 10−3 min−1) under UV irradiation. Besides, this was the only catalyst efficiently active in MB degradation under visible irradiation, these materials reach 10.4 % after 100 min under visible irradiation. Finally, chemical calculations supported the observed results, by means of TDDFT, EDA analysis, Fukui function and periodic DFT calculations. © 2024 Elsevier B.V.Universidad del Atlántico, UA, (ANID/FONDAP/1523A0006); Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECYT, (1231194, 1241917); Anillos de Ciencia y Tecnología, (ACT210057