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This study aims to develop and apply a novel methodology to assess the scope, benefits and challenges of distributed photovoltaic generation (DG-PV). The research provides a replicable framework applicable to any country, as long as official energy consumption data are available and the nation is seeking to modify its energy matrix as part of a sustainable transition through the design of renewable-energy-based policies. To support the viability of the proposal, data from the Ecuadorian electrical system for the period between 2014 and 2024 were analyzed using technical, operational and socio-economic indicators defined in the methodology. These include renewable participation, energy diversification, DG-PV, technical efficiency, regulatory index, operational resilience and electrical coverage. The investigation concludes with the definition of a Distributed Photovoltaic Integration Index (DPII), which can be used to measure a country’s progress toward the proper implementation of renewable energy. The DPII supports informed decision-making by allowing utilities and policymakers to prioritize distributed photovoltaic integration and compare alternative energy transition scenarios. In the case of Ecuador, a DPII of 0.170 is obtained for 2024 compared to a value of 0 for 2014. This result is mainly due to an increase in renewable energy participation (P1), which rose from 0.49 to 0.76 during this period, largely supported by hydropower expansion. This value was obtained because over the last ten years, Ecuador has committed to implementing active policies that incorporate renewable energies, as well as other aspects such as technical efficiency and the expansion of electrical coverage. This approach offers a replicable quantitative tool for evaluating the integration of DG-PV, providing key information for energy planning and for the formulation of policies that promote the decarbonization, decentralization and digitalization of the national electrical system.

In order to develop future projects in the field of photovoltaic solar energy, it is essential to accurately know the potential solar resources. There are many methods to estimate the incident solar radiation in a certain place. However, most of them are very expensive or do not have the ideal characteristics for good monitoring of a particular photovoltaic installation. For these reasons, an electronic device connected to the internet of things (IoT) is presented in this paper which manages to measure global radiation in photovoltaic applications. The device developed has been patented in the Spanish Patent and Trademark Office. It presents some features that make it very suitable to measure photovoltaic installations with the advantage of being a low cost and very reliable device. The device has been tested to determine global horizontal irradiance obtaining a correlation coefficient R2 = 0.994.

Background Cognitive impairment is twice more frequent in elderly with type 2 diabetes mellitus (DM). This study was conducted to determine the association between glycemic control and cognitive performance among community-dwelling elderly persons in Mexico. Methods Cross-sectional study conducted in individuals aged 60 years or elderly participating in the 2012 Mexican Health and Aging Study. Type 2 DM participants were classified in 3 groups according to their glycated hemoglobin levels (Hb A1c ): < 7% (intensive control), 7–7.9% (standard control) or ≥ 8% (poor control), and cognitive performance: low (CCCE ≤44 points), intermediate (44.1–59.52 points), or high (≥59.53 points). Multinomial logistic regression models were constructed to determine this association. Results Two hundred sixteen community-dwelling adults aged 60 and older with type 2 diabetes were selected. Subjects in the low cognitive performance group were older (69.7 ± 6.6 vs 65.86 ± 5.18 years, p  < .001) and had a lower educational level (2.5 ± 2.6 vs 7.44 ± 4.15 years, p  < .000) when compared to the high cognitive performance participants. Hb A1c  ≥ 8% was associated with having low (Odds Ratio (OR) 3.17, 95% CI 1.17–8.60, p  = .024), and intermediate (OR 3.23, 95% CI 1.27–8.20, p  = .014) cognitive performance; this trend was not found for Hb A1c 7.0–7.9% group. The multinomial regression analysis showed that the presence of Hb A1c  ≥ 8% (poor glycemic control) was associated with low (OR 3.17, 95% CI = 1.17–8.60, p  = .024), and intermediate (OR 3.23, 95% CI = 1.27–8.20, p  = .014) cognitive performance. After adjusting for confounding variables. Conclusions Glycemic control with a Hb A1c  ≥ 8% was associated with worse cognitive performance.

Background: Frailty, a state of increased vulnerability, could play a role in the progression of vascular dementia. We aim to describe the changes in cerebrovascular reactivity of older adults with frailty and vascular-type mild cognitive impairment (MCIv). Methods: This was a cross-sectional study. A comprehensive geriatric assessment, neuropsychological evaluation, and transcranial Doppler ultrasound (TCD) was performed on 180 participants who were allocated into four groups: healthy (n = 74), frail (n = 40), MCIv (n = 35), and mixed (frail + MCIv) (n = 31). ANOVA and Kruskal–Wallis tests were used for the analysis of continuous variables with and without normal distribution. Multinomial logistic regression was constructed to identify associated covariates. Results: Subjects in the mixed group, compared to healthy group, were older (75.0 ± 5.9 vs 70.3 ± 5.9 years; p < 0.001), showed lower education (9.3 ± 6.4 vs 12.2 ± 4.0 years; p = 0.054), greater frequency of diabetes (42% vs 12%; p = 0.005), worse cognitive performance (z = −0.81 ± 0.94), and reduced left medial-cerebral artery cerebrovascular reactivity (0.43 ± 0.42 cm/s). The mixed group was associated with age (odds ratio (OR) 1.16, 95% Confidence Interval (CI) = 1.06–1.27; p < 0.001), diabetes (OR 6.28, 1.81–21.84; p = 0.004), and Geriatric Depression Scale (GDS) score (OR 1.34, 95% CI = 1.09–1.67; p = 0.007). Conclusions: Frailty among older adults was associated with worse cognitive performance, diabetes, and decreased cerebral blood flow.

As the south-westernmost region of Europe, the Iberian Peninsula stands as a key area for understanding the process of modern human dispersal into Eurasia. However, the precise timing, ecological setting and cultural context of this process remains controversial concerning its spatiotemporal distribution within the different regions of the peninsula. While traditional models assumed that the whole Iberian hinterland was avoided by modern humans due to ecological factors until the retreat of the Last Glacial Maximum, recent research has demonstrated that hunter-gatherers entered the Iberian interior at least during Solutrean times. We provide a multi-proxy geoarchaeological, chronometric and paleoecological study on human?environment interactions based on the key site of Peña Capón (Guadalajara, Spain). Results show (1) that this site hosts the oldest modern human presence recorded to date in central Iberia, associated to pre-Solutrean cultural traditions around 26,000 years ago, and (2) that this presence occurred during Heinrich Stadial 2 within harsh environmental conditions. These findings demonstrate that this area of the Iberian hinterland was recurrently occupied regardless of climate and environmental variability, thus challenging the widely accepted hypothesis that ecological risk hampered the human settlement of the Iberian interior highlands since the first arrival of modern humans to Southwest Europe.

The reactions of acetone, 2,2,2-trifluoroacetone and hexafluoroacetone in methanesulfonic (MSA) and triflic acids (TFSA) with benzene have been studied at M06-2X/6-311+G(d,p) level using cluster-continuum model, where the carbonyl group is explicitly solvated by acid molecules. The introduction of a trifluoromethyl group into the ketone structure reduces the activation energy of the tetrahedral intermediates formation due to an increase of the electrophilicity of the carbonyl group and raises the activation and the reaction energies of the C-O bond cleavage in formed carbinol due to the destabilization of the corresponding carbocation. The introduction of the second trifluoromethyl group inhibits the hydroxyalkylation reaction due to a very strong increase of the reaction and activation energies of the C-O bond cleavage which becomes the rate determining step. The most important catalytic effect of TFSA compared to MSA is not the protonation of the ketone carbonyl, but the reduction of the activation and reaction energies of the carbinol C-O bond cleavage due to better protosolvation properties. Even for TFSA no complete proton transfer to carbonyl oxygen has been observed for free ketones. Therefore, the protonation energies of free ketones cannot be considered as a measure of ketone reactivity in the hydroxyalkylation reaction. Figure Reactions of ketones with aromatics in acid media

Several studies on adult fish movement from marine protected areas to zones open to fishing activity conclude spillover is present, but most of these investigations use indirect evidence and small-sized species of little commercial importance. This paper reports the effects of manipulating a density gradient on movements of large-sized and commercially-important fish across “Jardines de la Reina” Marine Reserve boundaries, using tagging methods and visual census. Tagging was carried out using dart tags and modified spearguns at an experimental and a control site. Density of fish was experimentally manipulated on the unprotected side of the boundary. Before experimental manipulation, fish density was similar in both experimental and control sites and on both sides of the boundaries. After manipulation, fish density in the unprotected side of experimental site declined dramatically and a strong gradient was established through the boundary. One month later, this forced gradient disappeared, returning to the situation at the beginning of the study. This last result is due to spillover effect: the mean distance traveled by fish increased 1.5 times (mean from below 200 m to more than 300 m), the mean emigration rate doubled and the immigration rate decreased, allowing density levels to recover after manipulation.

Herbivorous insects alter biogeochemical cycling within forests, but the magnitude of these impacts, their global variation, and drivers of this variation remain poorly understood. To address this knowledge gap and help improve biogeochemical models, we established a global network of 74 plots within 40 mature, undisturbed broadleaved forests. We analyzed freshly senesced and green leaves for carbon, nitrogen, phosphorus and silica concentrations, foliar production and herbivory, and stand-level nutrient fluxes. We show more nutrient release by insect herbivores at non-outbreak levels in tropical forests than temperate and boreal forests, that these fluxes increase strongly with mean annual temperature, and that they exceed atmospheric deposition inputs in some localities. Thus, background levels of insect herbivory are sufficiently large to both alter ecosystem element cycling and influence terrestrial carbon cycling. Further, climate can affect interactions between natural populations of plants and herbivores with important consequences for global biogeochemical cycles across broadleaved forests. This study examines the impact of herbivorous insects on biogeochemical cycling within forests. From a global network of 74 plots within 40 mature, undisturbed broadleaved forests, they show that background levels of insect herbivory are sufficiently large to alter both ecosystem element cycling and influence terrestrial carbon cycling.

Background Cognitive impairment is twice more frequent in elderly with type 2 diabetes mellitus (DM). This study was conducted to determine the association between glycemic control and cognitive performance among community-dwelling elderly persons in Mexico. Methods Cross-sectional study conducted in individuals aged 60 years or elderly participating in the 2012 Mexican Health and Aging Study. Type 2 DM participants were classified in 3 groups according to their glycated hemoglobin levels (HbA1c): <7% (intensive control), 7-7.9% (standard control) or ≥ 8% (poor control), and cognitive performance: low (CCCE ≤44 points), intermediate (44.1-59.52 points), or high (≥59.53 points). Multinomial logistic regression models were constructed to determine this association. Results 216 community-dwelling adults aged 60 and older with type 2 diabetes were selected. Subjects in the low cognitive performance group were older (69.7 ± 6.6 vs 65.86 ± 5.18 years, p <.001) and had a lower educational level (2.5 ± 2.6 vs 7.44 ± 4.15 years, p <.000) when compared to the high cognitive performance participants. HbA1c ≥8% was associated with having low (Odds Ratio (OR) 3.17, 95% CI 1.17-8.60, p=.024), and intermediate (OR 3.23, 95% CI 1.27-8.20, p=.014) cognitive performance; this trend was not found for HbA1c 7.0-7.9% group. The multinomial regression analysis showed that the presence of HbA1c ≥8% (poor glycemic control) was associated with low (OR 3.17, 95% CI = 1.17-8.60, p=.024), and intermediate (OR 3.23, 95% CI = 1.27-8.20, p=.014) cognitive performance. After adjusting for confounding variables. Conclusions Glycemic control with a HbA1c ≥ 8% was associated with worse cognitive performance.