We present a study of how photovoltaic (PV) module performance varies on continental scale. Mathematical models have been used to take into account shallow-angle reflectivity, spectral sensitivity, ...dependence of module efficiency on irradiance and module temperature as well as how the module temperature depends on irradiance, ambient temperature and wind speed. Spectrally resolved irradiance data retrieved from satellite images are combined with temperature and wind speed data from global computational weather forecast data to produce maps of PV performance for Eurasia and Africa. Results show that module reflectivity causes a fairly small drop of 2\%–4\% in PV performance. Spectral effects may modify the performance by up to \(\pm 6\)\%, depending on location and module type. The strongest effect is seen in the dependence on irradiance and module temperature, which may range from \(-\)20\% to +5\% at different locations.
•Biochemical composition of six Tunisian walnuts varieties (Juglans regia L.).•Tocopherols, alcohols, sterols, carotenoids and volatile compounds were analyzed.•Significant effect of genotype was ...observed.
The aim of this work was to study the content of tocopherols, sterols, triterpenic and aliphatic alcohols, carotenoids, and volatile compounds in the kernel oils from six walnut (Juglans regia L.) varieties. The levels of β-carotene ranged between 0.22 and 0.62mg/kg, followed by lutein (0.01–0.06mg/kg). The total content of tocopherol ranged from 186.5 to 436.2mg/kg of the extracted oil and the major isoform in all samples was γ-tocopherol. The most abundant phytosterol was β-sitosterol (974–1494mg/kg) followed by campesterol then Δ-5-avenasterol. The major triterpenic alcohol was cycloartenol (226.4–532.1mg/kg). Hexacosanol (9.71–28.15mg/kg) was the major aliphatic alcohol. The detected volatile compounds were pentanal, hexanal, nonanal, 2-decenal and hexanol. The statistical analysis showed significant differences between varieties, which are probably due to genetic factors.
After 34 years of research and findings in the Middle Pleistocene site of the Sima de los Huesos (SH) of the Sierra de Atapuerca (Burgos, Spain), we present an update of the estimation of the number ...of individuals (ENI) identified in the SH hominin assemblage. The last ENI, published in 2004, was 28. Although the number of specimens recovered has almost doubled since then and more complete information is now available, this new analysis suggests that the ENI is 29. Some individuals are still represented by only one or a few teeth and the upper and lower jaws of various individuals have not been completed. We suggest that the amateur cavers, who accessed the SH site for years looking for bear fossils, destroyed a significant number of hominin fossils. Despite this, we have a good picture of the group of hominins represented in the SH assemblage. Because complete corpses were accumulated in SH and it is a closed cavity, it is expected that a significant number of hominin fossils remains to be discovered. According to the previous estimates, the representation of females is greater than that of males. However, the observed sex ratio is not significantly different from the 1:1 ratio. With the exception of the possible presence of a child individual, most of the remaining 28 individuals are teenagers or young adults (24/28 = 0.857). The ages of death of SH hominins appear to conform to a catastrophic profile.
How the Sima de los Huesos was won Arsuaga, Juan‐Luis; Martínez, Ignacio; Gracia‐Téllez, Ana ...
Anatomical record (Hoboken, N.J. : 2007),
July 2024, Letnik:
307, Številka:
7
Journal Article
Recenzirano
Odprti dostop
Although the first discovery of a human fossil in the Sima de los Huesos took place in 1976, systematic excavations did not begin there until 1984. Since then, this site has been continuously ...excavated in month‐long camps. The site is dated by different radiometric techniques to between 430,000 and 300,000 years ago. Until the 2023 campaign, just over 7000 human fossils have been recovered, constituting the largest collection of fossils prior to Homo sapiens ever discovered. The fossils correspond to a minimum of 29 individuals of both sexes and different ages at death, from preadolescents to a specimen of advanced age. Comparative anatomy and ancient DNA studies both suggest that this is a population closely related to Homo neanderthalensis. The great variety and extraordinary quality of the fossils recovered have allowed us to carry out a series of investigations that have greatly increased our knowledge about the evolution of Homo in the Middle Pleistocene. Among the most important discoveries, it has been possible to establish body size and proportions, the confirmation that the origin of the accumulation of human fossils was of an anthropic nature, that those past humans took care of disabled individuals and who were capable of having an oral language almost as complex and efficient as that of our own species.
This work presents a validation of three satellite-based radiation products over an extensive network of 313 pyranometers across Europe, from 2005 to 2015. The products used have been developed by ...the Satellite Application Facility on Climate Monitoring (CM SAF) and are one geostationary climate dataset (SARAH-JRC), one polar-orbiting climate dataset (CLARA-A2) and one geostationary operational product. Further, the ERA-Interim reanalysis is also included in the comparison. The main objective is to determine the quality level of the daily means of CM SAF datasets, identifying their limitations, as well as analyzing the different factors that can interfere in the adequate validation of the products.
The quality of the pyranometer was the most critical source of uncertainty identified. In this respect, the use of records from Second Class pyranometers and silicon-based photodiodes increased the absolute error and the bias, as well as the dispersion of both metrics, preventing an adequate validation of the daily means. The best spatial estimates for the three datasets were obtained in Central Europe with a Mean Absolute Deviation (MAD) within 8–13W/m2, whereas the MAD always increased at high-latitudes, snow-covered surfaces, high mountain ranges and coastal areas. Overall, the SARAH-JRC's accuracy was demonstrated over a dense network of stations making it the most consistent dataset for climate monitoring applications. The operational dataset was comparable to SARAH-JRC in Central Europe, but lacked of the temporal stability of climate datasets, while CLARA-A2 did not achieve the same level of accuracy despite predictions obtained showed high uniformity with a small negative bias. The ERA-Interim reanalysis shows the by-far largest deviations from the surface reference measurements.
•Validation of daily means of CM-SAF satellite products over 313 ground stations•SARAH provides the best estimations of solar radiation over Europe.•Low quality pyranometers are a significant uncertainty source in the validation.
We present a new database of solar radiation at ground level for Eastern Europe and Africa, the Middle East and Asia, estimated using satellite images from the Meteosat East geostationary satellites. ...The method presented calculates global horizontal (G) and direct normal irradiance (DNI) at hourly intervals, using the full Meteosat archive from 1998 to present. Validation of the estimated global horizontal and direct normal irradiance values has been performed by comparison with high-quality ground station measurements. Due to the low number of ground measurements in the viewing area of the Meteosat Eastern satellites, the validation of the calculation method has been extended by a comparison of the estimated values derived from the same class of satellites but positioned at 0°E, where more ground stations are available. Results show a low overall mean bias deviation (MBD) of +1.63 Wm−2 or +0.73% for global horizontal irradiance. The mean absolute bias of the individual station MBD is 2.36%, while the root mean square deviation of the individual MBD values is 3.18%. For direct normal irradiance the corresponding values are overall MBD of +0.61 Wm−2 or +0.62%, while the mean absolute bias of the individual station MBD is 5.03% and the root mean square deviation of the individual MBD values is 6.30%. The resulting database of hourly solar radiation values will be made freely available. These data will also be integrated into the PVGIS web application to allow users to estimate the energy output of photovoltaic (PV) systems not only in Europe and Africa, but now also in Asia.
•ERA5 and COSMO-REA6 reduce the quality gap between reanalysis and satellite data.•ERA5 bias is similar to that of satellite data for inland regions with few clouds.•COSMO-REA6 is comparable to ERA5 ...for North and Central Europe.•The absolute error of reanalyses is large due to a deficient cloud prediction.•COSMO-REA6 underestimates due to the overestimation of aerosols.
This study examines the progress made by two new reanalyses in the estimation of surface irradiance: ERA5, the new global reanalysis from the ECMWF, and COSMO-REA6, the regional reanalysis from the DWD for Europe. Daily global horizontal irradiance data were evaluated with 41 BSRN stations worldwide, 294 stations in Europe, and two satellite-derived products (NSRDB and SARAH).
ERA5 achieves a moderate positive bias worldwide and in Europe of +4.05 W/m2 and +4.54 W/m2 respectively, which entails a reduction in the average bias ranging from 50% to 75% compared to ERA-Interim and MERRA-2. This makes ERA5 comparable with satellite-derived products in terms of the mean bias in most inland stations, but ERA5 results degrade in coastal areas and mountains. The bias of ERA5 varies with the cloudiness, overestimating under cloudy conditions and slightly underestimating under clear-skies, which suggests a poor prediction of cloud patterns and leads to larger absolute errors than that of satellite-based products. In Europe, the regional COSMO-REA6 underestimates in most stations (MBE = −5.29 W/m2) showing the largest deviations under clear-sky conditions, which is most likely caused by the aerosol climatology used. Above 45°N the magnitude of the bias and absolute error of COSMO-REA6 are similar to ERA5 while it outperforms ERA5 in the coastal areas due to its high-resolution grid (6.2 km).
We conclude that ERA5 and COSMO-REA6 have reduced the gap between reanalysis and satellite-based data, but further development is required in the prediction of clouds while the spatial grid of ERA5 (31 km) remains inadequate for places with high variability of surface irradiance (coasts and mountains). Satellite-based data should be still used when available, but having in mind their limitations, ERA5 is a valid alternative for situations in which satellite-based data are missing (polar regions and gaps in times series) while COSMO-REA6 complements ERA5 in Central and Northern Europe mitigating the limitations of ERA5 in coastal areas.
Scientific research is constantly striving to find molecules which are effective against excessive body fat and its associated complications. Taking into account the beneficial effects that ...resveratrol exerts on other pathologies through miRNA, the aim of the present work was to analyze the possible involvement of miRNAs in the regulation of adipogenic transcription factors peroxisome proliferator-activated receptor γ (pparγ), CCAAT enhancer-binding proteins α and β (cebpβ and cebpα) induced by resveratrol and its metabolites.
3T3-L1 maturing pre-adipocytes were treated during differentiation with 25 μM of trans-resveratrol (RSV), trans-resveratrol-3-O-sulfate (3S), trans-resveratrol-3'-O-glucuronide (3G) and trans-resveratrol-4'-O-glucuronide (4G). After computational prediction and bibliographic search of miRNAs targeting pparγ, cebpβ and cebpα, the expression of microRNA-130b-3p (miR-130b-3p), microRNA-155-5p (miR-155-5p), microRNA-27b-3p (miR-27b-3p), microRNA-31-5p (miR-31-5p), microRNA-326-3p (miR-326-3p), microRNA-27a-3p (miR-27a-3p), microRNA-144-3p (miR-144-3p), microRNA-205-5p (miR-205-5p) and microRNA-224-3p (miR-224-3p) was analyzed. Moreover, other adipogenic mediators such as sterol regulatory element binding transcription factor 1 (srebf1), krüppel-like factor 5 (klf5), liver x receptor α (lxrα) and cAMP responding element binding protein 1 (creb1), were measured by Real Time RT-PCR. As a confirmatory assay, cells treated with RSV were transfected with anti-miR-155 in order to measure cebpβ gene and protein expressions.
Of the miRNAs analyzed only miR-155 was modified after resveratrol and glucuronide metabolite treatment. In transfected cells with anti-miR-155, RSV did not reduce cebpβ gene and protein expression. 3S decreased gene expression of creb1, klf5, srebf1 and lxrα.
While RSV and glucuronide metabolites exert their inhibitory effect on adipogenesis through miR-155 up-regulation, the anti-adipogenic effect of 3S is not mediated via miRNAs.
Integrated photovoltaics are an emerging technology which can extend the range of electric vehicles. However, up to now there is a lack of a consensus method that would provide consumers with an ...estimate of the fraction of annual driving which could be covered by solar power generated onboard in different usage scenarios and locations. To address this, we assess the energy implications of vehicle integrated photovoltaics for a commuter car and light delivery van for six climatic regions and for typical daily usage profiles over a ten-year period. The analysis captures the energy needs for driving and cabin temperature control to an unprecedented level of detail. Our results reveal that the grid power needed to drive such vehicles on identical routes can vary by more than 44% between climate regions. In the best case the solar power generated can cover up to 35% of the driving range per year. This contribution can vary by a factor of 2.5 between different climates, from 1800 to 5100 km annually, considerably mitigating the effect of ambient conditions on electric range. We propose developing consumer labels for solar electric vehicles that would consider this variation according to climatic conditions. The method described in this paper could help to frame initial discussions for such labels. We identify further requirements for research and development, standardisation, and policy needs.
•Above 5000 km solar range possible for commuter car and van with integrated PV.•Ten year simulation reveals solar range differences by factor 2.5 across climates.•Over 44% difference in grid electricity needs across six climates globally.•At the moment vehicle integrated PV not financially viable.•Consumer labels for PVEV may be needed to inform about performance variations.
Previous studies of upper first molar (M1) crown shape have shown significant differences between Homo sapiens and Homo neanderthalensis that were already present in the European Middle Pleistocene ...populations, including the large dental sample from Atapuerca‐Sima de los Huesos (SH). Analysis of other M1 features such as the total crown base area, cusp proportions, cusp angles and occlusal polygon have confirmed the differences between both lineages, becoming a useful tool for the taxonomic assignment of isolated teeth from Late Pleistocene sites. However, until now the pattern of expression of these variables has not been known for the SH sample. This fossil sample, the largest collection from the European Middle Pleistocene, is generally interpreted as being from the direct ancestors of Neanderthals, and thus is a reference sample for assessing the origin of the Neanderthal morphologies. Surprisingly, our study reveals that SH M1s present a unique mosaic of H. neanderthalensis and H. sapiens features. Regarding the cusp angles and the relative occlusal polygon area, SH matches the H. neanderthalensis pattern. However, regarding the total crown base area and relative cusps size, SH M1s are similar to H. sapiens, with a small crown area, a strong hypocone reduction and a protocone enlargement, although the protocone expansion in SH is significantly larger than in any other group studied. The SH dental sample calls into question the uniqueness of some so‐called modern traits. Our study also sounds a note of caution on the use of M1 occlusal morphology for the alpha taxonomy of isolated M1s.
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