Electricity from wind and, to a lesser extent, solar energy is intermittent and not controllable. Unlike conventional power generation, therefore, this electricity is not suitable to supply base-load ...electric power. In the future, with greater penetration of these renewable sources, intermittency and control problems will become critical. Here, the authors explore the use of canonical correlation analysis (CCA) for analyzing spatiotemporal balancing between regional solar and wind energy resources. The CCA allows optimal distribution of wind farms and solar energy plants across a territory to minimize the variability of total energy input into the power supply system. The method was tested in the southern half of the Iberian Peninsula, a region covering about 350 000 km². The authors used daily-integrated wind and solar energy estimates in 2007 from the Weather Research and Forecasting (WRF) mesoscale model, at a spatial resolution of 9 km. Results showed valuable balancing patterns in the study region, but with a marked seasonality in strength, sign, and spatial coverage. The autumn season showed the most noteworthy results, with a balancing pattern extending almost over the entire study region. With location of reference wind farms and photovoltaic (PV) plants according to the balancing patterns, their combined power production shows substantially lower variability than production of the wind farms and PV plants separately and combined production obtained with any other locations. Atmospheric circulations associated with the balancing patterns were found to be significantly different between seasons. In this regard, synoptic-scale variability played an important role, but so did topographic conditions, especially near the Strait of Gibraltar.
Abstract
Exercise modulates both brown adipose tissue (BAT) metabolism and white adipose tissue (WAT) browning in murine models. Whether this is true in humans, however, has remained unknown. An ...unblinded randomized controlled trial (ClinicalTrials.gov ID: NCT02365129) was therefore conducted to study the effects of a 24-week supervised exercise intervention, combining endurance and resistance training, on BAT volume and activity (primary outcome). The study was carried out in the Sport and Health University Research Institute and the Virgen de las Nieves University Hospital of the University of Granada (Spain). One hundred and forty-five young sedentary adults were assigned to either (i) a control group (no exercise,
n
= 54), (ii) a moderate intensity exercise group (MOD-EX, n = 48), or (iii) a vigorous intensity exercise group (VIG-EX
n
= 43) by unrestricted randomization. No relevant adverse events were recorded. 97 participants (34 men, 63 women) were included in the final analysis (Control;
n
= 35, MOD-EX;
n
= 31, and VIG-EX;
n
= 31). We observed no changes in BAT volume (Δ Control: −22.2 ± 52.6 ml; Δ MOD-EX: −15.5 ± 62.1 ml, Δ VIG-EX: −6.8 ± 66.4 ml; P = 0.771) or
18
F-fluorodeoxyglucose uptake (SUVpeak Δ Control: −2.6 ± 3.1 ml; Δ MOD-EX: −1.2 ± 4.8, Δ VIG-EX: −2.2 ± 5.1;
p
= 0.476) in either the control or the exercise groups. Thus, we did not find any evidence of an exercise-induced change on BAT volume or activity in young sedentary adults.
The reliance of a future carbon-free horizon is strongly aligned with the long-term energy storage avenues which are completely derived from renewable energy resources. Ammonia with its high energy ...content and density can perform as a decent candidate for buffering the short-term storage options. However, the current NH3 production majorly feeding the current huge desire for ammonia is dominated by the conventional nonrenewable Haber–Bosch (H–B) process route, thus continuously damaging the target of carbon neutrality goals. High-purity hydrogen (H2) gas is an essential precursor for the H–B process; however, it is a significant energy consumer (about 2% of the global energy supply) and contributes over 420 million tons of CO2/annum. Therefore, the research on the renewable synthesis of nitrogen-based energy carriers (such as ammonia) from the direct electrochemical, photocatalytic, or plasma catalytic processes; its conversion; and utilization to the potential derivatives has been a hot topic in the past few decades. A prospective analysis of the highly appealing processes has been summarized in this study, which could facilitate the adaption of renewable alternatives as an effective approach for zero carbon emission, paving the excellent pathways along the road to the development of nitrogen-based energy technologies, especially the targeted development of ammonia. Further, this Review covers the current and future impacts of the H–B process, the development of aspiring ammonia synthesis routes (via electro, photo, bio, chemical loop, or plasma catalysis), and its conversion and utilization to the renewable derivatives in terms of fabrication of model catalysts, advanced characterization technology, and efficient device design.
Biominerals are inorganic-organic hybrid composites formed via self-assembled bottom up processes under mild conditions. Biominerals show interesting physical properties, controlled hierarchical ...structures and robust remodeling or repair mechanisms. Biological processes associated with biominerals remain to be developed into practical engineering processes. Therefore, the formation of biominerals is inspiring for the design of materials, especially those fabricated at ambient temperatures.
The study described herein involves the influence of chicken outer eggshell membrane on the type of calcium carbonate (CaCO3) polymorph deposited on the shell of the land snail Helix aspersa during the repair process after an injury. A piece of snail shell was removed by perforating a hole from the largest body whorl. The operated area was left either uncovered or covered with either a thermoplastic flexible polyolefin-based film Parafilm® or a piece of chicken eggshell membrane.
The repaired shells of control and experimental animals were analyzed using SEM, EDS, Raman and FTIR spectroscopies.
We found that in the presence of eggshell membrane, the polymorph deposited on the substratum during the first hours resembles calcite, the polymorph present in eggshell normal formation, but at 24 and 48h, when snail mantle cells produced their normal organic matrix (mainly β-chitin plus proteins and proteoglycans), the polymorph deposited is aragonite, the characteristic polymorph of Helix shell.
Therefore, the eggshell membrane influences the type of polymorph, but only in the initial stages of biomineral deposition, before an organic matrix layer is deposited by the snail.
Biogas methanation emerges as a prominent technology for converting biogas into biomethane in a single step. Furthermore, this technology can be implemented at biogas plant locations, supporting ...local economies and reducing dependence on large energy producers. However, there is a lack of comprehensive studies on biogas methanation, particularly regarding the technical optimization of operational parameters and the profitability analysis of the overall process. To address this gap, our study represents a seminal work on the technical optimization of biogas methanation obtaining an empirical model to predict the performance of biogas methanation. We investigate the influence of operational parameters, such as reaction temperature, H2/CO2 ratio, space velocity, and CO2 share in the biogas stream through an experimental design. Based on previous research we selected a nickel supported on ceria-alumina catalyst; being nickel a benchmark system for methanation process such selection permits a reliable data extrapolation to commercial units. We showcase the remarkable impact of studied key operation parameters, being the temperature, the most critical factor affecting the reaction performance (ca. 2 to 5 times higher than the second most influencing parameter). The impact of the H2/CO2 ratio is also noticeable. The response surfaces and contour maps suggest that a temperature between 350 and 450 °C and an H2/CO2 ratio between 2.5 and 3.2 optimize the reaction performance. Further experimental tests were performed for model validation and optimization leading to a reliable predictive model. Overall, this study provides validated equations for technology scaling-up and techno-economic analysis, thus representing a step ahead towards real-world applications for bio-methane production.
•An empirical model to predict the performance of biogas methanation was built.•The influence of the main operational parameters was studied.•The temperature is the most critical factor affecting the reaction performance.•The impact of the H2/CO2 ratio is also noticeable.•Temperature of 350–450 °C and H2/CO2 ratio of 2.5–3.2 optimize the reaction.
Abstract Environmental enrichment (EE) produces a remarkable degree of structural and functional plasticity in the hippocampus and possible mediators of these changes, such as glucocorticoid ...receptors (GRs), are of considerable interest. GRs are richly expressed in the hippocampus and they are involved in the adaptation to stressors and facilitate active coping in anxious situations. In this study, we assessed the effect of an EE protocol (24 h/day during 69 days) in adult Wistar rats on the activity in the elevated-zero maze (EZM), performance in the holeboard task (HB) and we also examined the changes in the glucocorticoid receptors (GRs) expression in the dorsal hippocampus (CA1, CA3 and DG). Our EE protocol reduced anxious behaviors in the EZM, so the animals spent more time and made more entries into the open sections. In the HB task, the enriched group showed more explorative behavior, a reduction of anxiety-related behaviors and a better cognitive performance compared to non-enriched animals. With regard to the GR expression, the EE condition produced an increase in the number of immunopositive cells for GRs in CA1, CA3 and DG. These results suggest that the better performance of enriched animals could be mediated in part by the increase of GRs in the dorsal hippocampus, which may alter the hippocampal neuronal function and accordingly, the anxiety levels, the spatial memory performance and the exploration levels in these animals.
We suggest that quintessential vacuum energy could be the source of right-handed neutrino masses that feed the seesaw mechanism, which may provide the observed small masses of light standard ...neutrinos. This idea is naturally implemented in the cosmological unification model based on the global SO(1,1) symmetry, where the early inflation and late-time accelerated expansion of the Universe are driven by the degrees of freedom of a doublet scalar field. In this model, the SO(1,1) custodial symmetry naturally provides the coupling between the Standard Model singlet fermion and quintessence, which sources neutrino masses. We also show that the model predicts a highly suppressed contribution to the relativistic degrees of freedom from quintessential quanta during any late Universe epoch, ensuring the consistency of the model.
•Egocentric and allocentric memory were assessed with a card placing test.•Gender differences were observed in Egocentric and Allocentric spatial memory.•Spatial memory was associated with ...visuospatial span and working memory.•Women achieved better scores on the Allocentric test than on the Egocentric test.
Spatial memory allows us to locate objects and organisms in space and move through the environment. We frequently use two strategies for this purpose: egocentric, related to the viewer’s perspective, and allocentric, associated with environmental cues. This ability is usually assessed by 2D or virtual reality-based tasks. Gender differences have been reported on these tasks. We designed two card-placing tasks with the aim of assessing egocentric and allocentric spatial memory in a real environment. This task makes it possible to separately compare egocentric and allocentric strategies, providing participants with 3D information naturally present in daily orientation activities. We will assess the performance of male and female young adults on the two strategies. Ninety-four subjects were recruited and performed egocentric and allocentric spatial memory card placing tasks. Spatial Span, forward and backward, was also assessed using the Cambridge Neuropsychological Assessment Battery (CANTAB), and the brief version of Benton’s Judge of Line Orientation Test (JoLO) was used to evaluate the ability to judge spatial relations. Our results show that men outperformed women on both spatial memory tasks. Women performed better on Allocentric tasks than on Egocentric tasks, whereas men’s scores did not show differences between strategies. Spatial memory performance on the card placing tasks was significantly correlated with performance on the backward visuospatial span from the CANTAB. This study supports the existence of gender differences in spatial memory functioning, and it provides novel tools for the neuropsychological assessment of spatial memory.
Thevetia peruviana (T. peruviana) has been considered as a potentially important plant for industrial and pharmacological application. Among the number of compounds which are produced by T. ...peruviana, antioxidants and polyphenols are of particular interest due to their benefits on human health. Cell suspension cultures of T. peruviana were established under different conditions: 1) constant illumination (24h/day) at different light wavelengths (red, green, blue, yellow and white), 2) darkness and 3) control (12h/12h: day light/dark) to investigate their biomass, substrate uptake, polyphenols production and oxidizing activity. The results showed biomass concentrations between 17.1g dry weight (DW)/l (green light) and 18.2g DW/l (control) after 13days. The cultures that grew under green light conditions consumed completely all substrates after 10days, while other cultures required at least 13days or more. The total phenolic content was between 7.21 and 9.46mg gallic acid (GA)/g DW for all light conditions. In addition the ferric reducing antioxidant power and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid antioxidant activity ranged from 5.41–6.58mg ascorbic acid (AA)/g DW and 82.93–110.39μmol Trolox/g DW, respectively. Interestingly, the samples which grew under the darkness presented a higher phenolic content and antioxidant capacity when compared to the light conditions. All together, these results demonstrate the extraordinary effect of different lighting conditions on polyphenols production and antioxidant compounds by T. peruviana.
•Different light wavelengths did not present effect in cell growth.•Cell cultures of T. peruviana present a strictly heterotrophic cell growth.•Light has a deleterious effect on the production of phenols and antioxidant capacity.•Cells of T. peruviana exhibit higher antioxidant capacity compare to in vivo plants.