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Effects of D-Tagatose on Cariogenic Risk: A Systematic Review of Randomized Clinical Trials
Get PDFDental caries remains a prevalent chronic disease driven by dysbiosis in the oral biofilm, with Streptococcus mutans playing a central role in its pathogenesis. Objective: This study aimed to assess the effect of D-tagatose on cariogenic risk by analyzing randomized clinical trials (RCTs). Methods: A systematic literature review was conducted targeting RCTs published up to 2024 in eight databases and two gray literature sources. The search strategy utilized Medical Subject Headings (MeSHs) and relevant keywords combined via Boolean operators using the query “Tagatose OR D-tagatose AND Dental Caries”. Eligible studies must evaluate the impact of D-tagatose on cariogenic risk, as indicated by reductions in colony-forming units (CFUs) and improvements in salivary pH levels in treatment groups. Results: From 1139 retrieved records, three studies met the inclusion criteria. These studies consistently demonstrated significant reductions in CFU counts and improvements in salivary pH levels in groups treated with D-tagatose compared to controls using other non-caloric sweeteners or placebos (p < 0.01). However, the quality of the evidence was heterogeneous, with certain methodological concerns. Conclusions: Although the findings suggest potential benefits of D-tagatose in reducing cariogenic risk, limitations such as small sample sizes and variability in study methodologies warrant caution. Further robust investigations are needed to substantiate these promising results and support the integration of D-tagatose into oral care formulations aimed at reducing cariogenic risk
Demonstrating the substitutional doping of erbium (Er) in BiFeO3 nanoparticles for the enhanced solar-driven photocatalytic activity
No full textThis study reports the synthesis of erbium (Er)-doped bismuth ferrite (BiFeO3/BFO) nanoparticles at varying molar concentrations (5, 10, and 15 %) using a sol-gel method. X-ray diffraction (XRD) analysis reveals a structural transformation from rhombohedral to orthorhombic upon Er3+ doping, confirming the successful incorporation of Er3+ ions into the BFO lattice. High-resolution transmission electron microscopy (HRTEM) images show that Er-doping leads to a reduction in particle size and a modification of the surface morphology. The bandgap of the Er-doped BFO samples decreases from 2.34 to 2.15 eV with increasing Er content, attributed to the formation of new Er 4f energy levels within the band structure. The magnetic properties of the samples also improve with increasing Er concentration. Photoluminescence (PL) spectra show reduced PL intensity for the 10 % Er-doped BFO sample, indicating a decrease in recombination rates, while electrochemical impedance spectroscopy (EIS) reveals a reduction in charge transfer resistance. Among the samples, the 10 % Er-doped BFO photocatalyst exhibits the highest photocatalytic efficiency. This enhanced activity is attributed to two key factors: efficient separation and migration of photogenerated charge carriers, and a reduced recombination rate of electron-hole pairs, both driven by the rare-earth doping in BFO. Radical trapping experiments further identify hydroxyl (OH•) radicals as the primary species responsible for photocatalytic degradation. This study provides valuable insights into the tunability of BFO's bandgap energy and photocatalytic properties through Er doping
Non-Lorentzian supergravity and kinematical superalgebras
Get PDFIn this paper, we present and classify the supersymmetric extensions of extended kinematical algebras, at the basis of non-Lorentzian physics theories. The diverse kinematical superalgebras are here derived by applying non- and ultra-relativistic expansion procedures involving different semigroups. We then build three-dimensional Chern-Simons non-Lorentzian supergravity theories based on such (extended) kinematical superalgebras, providing the supersymmetry transformation laws of the fields and the field equations of the models, which correspond to the vanishing of the curvature two-forms. In fact, the expansion procedure adopted allows to automatically end up with a non-degenerate bilinear invariant trace for the (extended) kinematical superalgebras. The latter is a crucial ingredient of the Chern-Simons field-theoretical formulation, as it allows to include a kinetic term for each gauge field of the theory, implying the vanishing of the curvature two-forms as field equations
A Low-Cost Evaluation Tool for Synchronization Methods in Three-Phase Power Systems
Get PDFThe use of renewable energy sources (RESs) together with energy storage systems (ESSs) allows for smoothing power variations, thus improving power backup capabilities and power quality in the electric power grid. These applications require power converters to transfer energy between the renewable generator or energy storage and the power grid. In any case, the control algorithm of the power converter requires the synchronization method to provide a correct estimation of the instantaneous voltage of the power grid. This work provides engineers and researchers with an accessible platform at a low cost (less than USD 100) and a methodology for the experimental validation of digital synchronization algorithms as a step before their implementation in grid-connected equipment. The methodology evaluates the performance of the digital algorithms when there are variations in amplitude, frequency, phase, and harmonic content in the emulated three-phase power grid, as well as the execution times (tex), while a digital platform emulates the electrical signals and generates reference signals for the evaluation. To illustrate this proposal, two synchronization algorithms—SRF-PLL and DSOGI-PLL with a low-pass filter—are implemented in a digital controller and tested. The evaluation tool confirms the algorithms’ performance and shows that the execution time of DSOGI-PLL is 91% longer than that of SRF-PLL, which is well known in the literature
Análisis de la calidad del sueño y su impacto en la composición corporal en culturistas naturales el día previo a la competencia
Get PDFIntroduction: Bodybuildingis a sport that evaluates athletes based on their muscle mass, sym-metry, and muscle definition, unlike conventional sports that are usually based on athletic per-formance in competition. Objective: The objective of the study was to determine the relationship between fat mass (FM) and skeletal muscle mass (SMM)through bioimpedancewith sleep quality in Chilean natural bodybuilders on pre-competition day. Methodology: Twenty-sixnatural bodybuilders participated in the WNBF Chilean champion-ship. The objective was to evaluate body composition toobtain data regarding SMM and FM. Additionally, thePSQI was applied. Results: significant relationships were obtained with SMM andPSQI (p= 0, 02, R = -0,38, R²= 0.14) and a moderate correlation between FM and PSQI (p= 0.04, R = 0.40, R²= 0.15). Sleep efficiency showed a negative correlation (p= 0.001, R = -0.55, R²= 0.31) with FM and a positive correlation (p = 0.002, R = 0.58, R²= 0.34) with SMM. Sleep duration showed a negative corre-lation (p = 0.024, R = -0.39, R²= 0.15) with FM and a positive correlation (p = 0.021, R = 0.45, R²= 0.20) with SMM. Discussion: A lack of sufficient sleep has been linked to adverse effects on body composition, including reduced fat loss and muscle gain. Additionally, insufficient sleep has been associated with a decline in athletic performance.Conclusions: The findings of this study indicate that poor sleep quality is associated with higher body fat and better sleep quality with a higher skeletal muscle mass, underscoring the signifi-cance of sleep for achieving optimal body composition and performance in natural bodybuild-ers
Fatty acid profiles of highly migratory resources from the Southeastern Pacific Ocean, Chile: a potential tool for biochemical and nutritional traceability
Get PDFThe traceability of fish species and their resulting food products is essential to maintain the global supply of these goods, allowing us to distinguish and reconstruct the origin and history of their production chain. One way to trace food is through biochemical determinations, which aid in identifying their geographical origin quickly. This study analyzed the fatty acid (FA) profiles of highly migratory fishery resource species (HMRS) from the Southeastern Pacific Ocean (SEPO), and their use as potential tools to determine the geographic origin and nutritional condition of these marine resources. The fatty acids (FAs) presented in fillet or muscle tissue of 18 HMRS were measured as FA methyl esters by gas chromatography. Our results reveal that the swordfish Xiphias gladius presented the greatest variety of FAs, strongly characterized by the presence of saturated, monounsaturated, and polyunsaturated FAs. A similar trend of high diversity in all classes of FAs was observed in tuna species (i.e., Thunnus alalunga; T. albacares; T. obesus), oilfish (Ruvettus pretiosus) and escolar fish (Lepidocybium flavobrunneum). In turn, Lampris guttatus, Makaira indica, and Tetrapturus audax presented an intermediate variety of FAs and the highest amount of saturated and monounsaturated FAs of the evaluated species. Finally, Luvarus imperialis, Coryphaena hippurus and the sharks (Lamna nasus; Alopias vulpinus; Prionace glauca; Isurus oxyrinchus; Sphyrna zygaena) presented a low diversity of FAs, with only saturated FAs strongly predominating. Regarding the total concentration of FAs, the highest average values were recorded in X. gladius, L. flavobrunneum and R. pretiosus. The present study revealed notable differences in the FA compositions of the muscle of diverse HMRS from the SEPO off the coast of Chile, with the swordfish showing the healthiest FAs (i.e., mono and polyunsaturated) for human consumption. The data on FAs collected for HMRS could be used as a reference to characterize the FA profiles of other fisheries in the SEPO (e.g., coastal pelagic fishes). In an ecosystem approach, our findings help us to understand how essential nutrients (i.e., FA biomolecules) are transferred through the marine food web in the SEPO, revealing the diet type and/or feeding habits of HMRS considered as top predators. Furthermore, identifying the FA profiles of fishery resources at a spatial level provides crucial information for their management and conservation, particularly in those resources that are overexploited and also have a critical nutritional importance for human consumption
Construcción de identidad docente: Trascendencia de las experiencias de formación teórica y práctica del futuro profesorado de enseñanza media
No full textFree-Weight and Smith-Machine Squats: Do They Produce Selective Chronic Adaptations in the Effectiveness of Force Application?
No full textBackground: Force is applied more in the backward direction during Smith-machine (SM) squats than in free-weight (FW) squats, although it is still uncertain whether this discrepancy will result in chronic adaptations in that direction. Purpose: We aimed to assess the effects of an 8-week squat training with FW or SM on longitudinal ground-reaction forces recorded during both FW and SM squats. Methods: Twenty sport-science students (9 female) were assigned to either an FW or SM training group, balanced by sex and relative strength. The 8-week training (2 sessions/wk) consisted of 4 sets of back squats at 70% of 1-repetition maximum (1-RM) with 20% velocity loss. Pretesting and posttesting assessed ground-reaction forces during a single set of 10 repetitions at ~45% and ~70% 1-RM, performed with FW in one session and SM in another session. Results: Squat type (FW or SM) had minimal influence on longitudinal impulse, its components (mean force and time), or the angle of the resultant ground-reaction force. The only significant difference was observed in longitudinal impulse during the propulsive phase at ~70% 1-RM in the SM squat (P = .037), where the FW training group exhibited a reduction in longitudinal impulse posttraining, while the SM training group showed an increase. Conclusions: An 8-week squat training does not modify the effectiveness of force application, regardless of training or testing squat type. Therefore, both squat variations can be used interchangeably without systematically influencing the direction of force production, allowing athletes to select based on preference, equipment availability, or sport-specific demands
Changing quantile distributive growth cycles
No full textThis paper examines the changes in the dynamic interactions between short-run economic growth (EG) and functional income distribution (ID) before and during contemporary neoliberal capitalism in the USA. We estimate structural quantile vector autoregression models, thus studying the dynamic changes that have occurred in all parts of the conditional probability distributions of both EG and ID. First, we find evidence of important reductions in the profit-led effect across the whole probability distribution of EG during neoliberalism. Second, we find that profit squeeze dynamics have decreased at most parts of the probability distribution of ID but have increased its effect in the left tail of the latter, thus becoming more heterogeneous across the probability distribution of ID. Although the underlying transmission mechanisms have remained unaltered across the two periods, our results highlight that the interactions between EG and ID have become a more complex phenomenon to study since the mid-1980s
Relationship Between Executive Function Subdomains and Postural Balance in Community-Dwelling Older Adults
No full textBackground: Executive function (EF) deficits are a significant risk factor for falls among older adults (OAs). However, relationship between EF subdomains (shifting, updating, and inhibition), postural balance (PB), and fall risk in healthy OAs, remains poorly understood. Objective: This study aimed to investigate the relationship between EF subdomains (shifting, updating, and inhibition) and PB, and to assess their impact on risk of falls in community-dwelling OAs. Methods: A cross-sectional study involving 50 OAs aged over 60 years (average age of 72 years) was conducted. Participants underwent assessments of EF subdomains and PB using validated tests. A correlation analysis was employed to examine the relationships between EF and PB. Results: The study revealed significant correlations between subdomains and PB. Mental set shifting (r = −.539; p < .001) and inhibition (r = −.395; p = .050) exhibited inverse relationships with PB. Stepwise multiple linear regression showed that Trail Making Test Part B was associated with the PB (R2 = .42, p < .001). Conclusion: These findings highlight the importance of assessing EF subdomains, particularly shifting and inhibition, to identify risk of falls. Trail Making Test Part B largely explains the variability of the PB. Integrating PB assessments and EF training, such as the Mini-BESTest, into routine care can be vital for fall prevention strategies. Significance/Implications: This knowledge underscores the need for cognitive training interventions focusing on shifting and inhibition to enhance PB and potentially reduce falls. Additionally, incorporation of EF assessment tools as Trail Making Test Part B and the Mini-BESTest into routine clinical practice for community-dwelling OAs is recommended to address fall prevention strategies