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New biomass crop hybrids for bioeconomic expansion require yield projections to determine their potential for strategic land use planning in the face of global challenges. Our biomass growth simulation incorporates radiation interception and conversion efficiency. Models often use leaf area to predict interception which is demanding to determine accurately, so instead we use low-cost rapid light interception measurements using a simple laboratory-made line ceptometer and relate the dynamics of canopy closure to thermal time, and to measurements of biomass. We apply the model to project the European biomass potentials of new market-ready hybrids for 2020–2030. Field measurements are easier to collect, the calibration is seasonally dynamic and reduces influence of weather variation between field sites. The model obtained is conservative, being calibrated by crops of varying establishment and varying maturity on less productive (marginal) land. This results in conservative projections of miscanthus hybrids for 2020–2030 based on 10% land use conversion of the least (productive) grassland and arable for farm diversification, which show a European potential of 80.7–89.7 Mt year−1 biomass, with potential for 1.2–1.3 EJ year−1 energy and 36.3–40.3 Mt year−1 carbon capture, with seeded Miscanthus sacchariflorus × sinensis displaying highest yield potential. Simulated biomass projections must be viewed in light of the field measurements on less productive land with high soil water deficits. We are attempting to model the results from an ambitious and novel project combining new hybrids across Europe with agronomy which has not been perfected on less productive sites. Nevertheless, at the time of energy sourcing issues, seed-propagated miscanthus hybrids for the upscaled provision of bioenergy offer an alternative source of renewable energy. If European countries provide incentives for growers to invest, seeded hybrids can improve product availability and biomass yields over the current commercial miscanthus variety.  相似文献   
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Saint Peter and Saint Paul's Archipelago (SPSPA), one of the smallest and most isolated island groups in the world, is situated on the Mid-Atlantic Ridge, between Brazil and the African continent. SPSPA has low species richness and high endemism; nonetheless, the diversity of fishes from deep habitats (>30 m depth) had not been previously studied in detail. Several expeditions conducted between 2009 and 2018 explored the shallow and deep reefs of SPSPA using scuba, closed-circuit rebreathers, manned submersibles, baited remote underwater stereo-videos (stereo-BRUV) and fishing between 0 and 1050 m depth. These expeditions yielded 41 new records of fishes for SPSPA: 9 in open waters, 9 in shallow waters (0–30 m), 8 in mesophotic ecosystems (30–150 m) and 15 in deeper reefs (>150 m). Combined with literature records of adult pelagic, shallow and deep-reef species, as well as larvae, the database of the fish biodiversity for SPSPA currently comprises 225 species (169 recorded as adult fishes and 79 as larvae, with 23 species found in both stages). Most of them (112) are pelagic, 86 are reef-associated species and 27 are deep-water specialists. Species accumulation curves show that the number of fish species has not yet reached an asymptote. Whereas the number of species recorded in SPSPA is similar to that in other oceanic islands in the Atlantic Ocean, the proportion of shorefishes is relatively lower, and the endemism level is the third highest in the Atlantic. Twenty-nine species are listed as threatened with extinction. Observations confirm the paucity of top predators on shallow rocky reefs of the island, despite the presence of several pelagic shark species around SPSPA. Because all of the endemic species are reef associated, it is argued that the new marine-protected areas created by the Brazilian government do not ensure the protection and recovery of SPSPA's biodiversity because they allow exploitation of the most vulnerable species around the archipelago itself. This study suggests a ban on reef fish exploitation inside an area delimited by the 1000 m isobath around the islands (where all known endemics are concentrated) as the main conservation strategy to be included in the SPSPA management plan being prepared by the Brazilian government.  相似文献   
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Two new species of Culicoides Latreille of the Neotropical subgenus Mataemyia Vargas are described and illustrated based on female specimens from Juruti, Pará, Brazil and compared with their similar congeners. This paper also presents a diagnosis of the subgenus Mataemyia and a systematic key for the identification of the 19 species of the subgenus.  相似文献   
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The positive regulation of insulin pathway in skeletal muscle results in increased activity of the mammalian target of rapamycin (mTOR), a positive effector of mRNA translation rate and protein synthesis. Studies that assess the activity of this protein in response to chronic high-fat diet (HFD) are scarce and controversial, and to date, there are no studies evaluating the mTOR pathway in infants exposed to gestational and postgestational HFD. This study investigated the effect of maternal HFD on skeletal muscle morphology and on phosphorylation of proteins that comprise the intracellular mTOR signaling pathway in soleus muscle of offspring at weaning. For this purpose, 10 days prior to conception, 39 female Wistar rats were randomly assigned to either control diet (CTL) or HFD. Later, rats were distributed into four groups according to gestational and postpregnancy diet: CTL/CTL (n=10), CTL/HF (n=11), HF/HF (n=10) and HF/CTL (n=8). After 21 days of lactation, pups were killed, and blood samples and soleus and gastrocnemius skeletal muscle were collected for analysis. We observed an influence of maternal postgestational diet, rather than gestational diet, in promoting an obese phenotype, characterized by body fat accumulation, insulin resistance and high serum leptin, glucose, triglycerides and cholesterol levels (P<.05). We have also detected alterations on skeletal muscle morphology — with reduced myofiber density — and impairment on S6 kinase 1 and 4E binding protein-1 phosphorylation (P<.05). These results emphasize the importance of maternal diet during lactation on muscle morphology and on physiological adaptations of infant rats.  相似文献   
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Lignin is a key factor limiting saccharification of lignocellulosic feedstocks. In this comparative study, various lignin methods—including acetyl bromide lignin (ABL), acid detergent lignin (ADL), Klason lignin (KL), and modified ADL and KL determination methods—were evaluated for their potential to assess saccharification efficiency. Six diverse accessions of the bioenergy crop miscanthus were used for this analysis, which included accessions of Miscanthus sinensis, Miscanthus sacchariflorus, and hybrid species. Accessions showed large variation in lignin content. Lignin estimates were different between methods, but (highly) correlated to each other (0.54?≤?r?≤?0.94). The strength of negative correlations to saccharification efficiency following either alkaline or dilute acid pretreatment differed between lignin estimates. The strongest and most consistent correlations (?0.48?≤?r?≤??0.85) were obtained with a modified Klason lignin method. This method is suitable for high throughput analysis and was the most effective in detecting differences in lignin content (p?<?0.001) between accessions.  相似文献   
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Movement of livestock production within a country or region has implications for genetics, adaptation, well-being, nutrition, and production logistics, particularly in continental-sized countries, such as Brazil. Cattle production in Brazil from 1977 to 2011 was spatialized, and the annual midpoint of production was calculated. Changes in the relative production and acceleration of production were calculated and spatialized using ARCGIS®. Cluster and canonical discriminant analyses were performed to further highlight differences between regions in terms of cattle production. The mean production point has moved from the Center of Minas Gerais State (in the southeast region) to the North of Goiás State (in the Midwest region). This reflects changes in environmental factors, such as pasture type, temperature and humidity. Acceleration in production in the northern region of Brazil has remained strong over the years. More recently, “traditional” cattle-rearing regions, such as the south and southeast, showed a reduction in growth rates as well as a reduction in herd size or internal migration over the period studied. These maps showed that this movement tends to be gradual, with few regions showing high acceleration or deceleration rates.  相似文献   
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International Journal of Primatology - Hybridization is relatively well documented among Old World primates, but poorly investigated among New World monkeys. We investigated hybridization between...  相似文献   
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