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991.
PurposeTo investigate the impact of compressed sensing – sensitivity encoding (CS-SENSE) acceleration factor on the diagnostic quality of magnetic resonance images within standard brain protocol.MethodsThree routine clinical neuroimaging sequences were chosen for this study due to their long acquisition time: T2-weighted turbo spin echo (TSE), fluid - attenuated inversion recovery (FLAIR), and 3D time of flight (TOF). Fully sampled reference scans and multiple prospectively 2x to 5x undersampled CS scans were acquired. Retrospectively, undersampled scans were compared to fully sampled scans and visually assessed for image quality and diagnostic quality by three independent radiologists.ResultsImages obtained with CS-SENSE accelerated acquisition were of diagnostically acceptable quality at up to 3x acceleration for T2 TSE (average qualitative score 3.53 on a 4-point scale, with the acquisition time reduction of 64%), up to 2x for FLAIR (average qualitative score 3.27, with the acquisition time reduction of 43%) and 4x acceleration for 3D TOF sequence (average qualitative score 3.13, with the acquisition time reduction of 73%). There were no substantial differences between the readers’ diagnostic quality scores (p > 0.05).ConclusionsCS-SENSE accelerated T2 TSE, FLAIR, and 3D TOF sequences of the brain show image quality similar to that of conventional acquisitions with reduced acquisition time. CS-SENSE can moderately reduce scan time, providing many benefits without losing the image quality. 相似文献
992.
Multiscale drivers of carabid beetle (Coleoptera: Carabidae) assemblages in small European woodlands
Ronan Marrec Vincent Le Roux Ludmilla Martin Jonathan Lenoir Jrg Brunet Sara A. O. Cousins Pallieter De Smedt Marc Deconchat Martin Diekmann Steffen Ehrmann Emilie Gallet‐Moron Brice Giffard Jaan Liira Jessica Lindgren Alicia Valdes Kris Verheyen Monika Wulf Guillaume Decocq 《Global Ecology and Biogeography》2021,30(1):165-182
993.
Mirco Bundschuh Jochen P. Zubrod Theo Wernicke Marco Konschak Leon Werner Carsten A. Brühl Patrick Baudy Ralf Schulz 《Ecology and evolution》2021,11(9):4353
Biodiversity is under pressure worldwide, with amphibians being particularly threatened. Stressors related to human activity, such as chemicals, are contributing to this decline. It remains, however, unclear whether chemicals exhibiting a fungicidal activity could indirectly affect tadpoles that depend on microbially conditioned leaf litter as food source. The indirect effect of fungicides (sum concentration of a fungicide mixture composed of azoxystrobin, carbendazim, cyprodinil, quinoxyfen, and tebuconazole: 100 µg/L) on tadpoles was assessed relative to leaf litter colonized by microbes in absence of fungicides (control) and a worst‐case scenario, that is leached leaf litter without microbial colonization. The quality of leaf litter as food for tadpoles of the European common frog (Rana temporaria) was characterized through neutral lipid fatty acid profiles and microbial sum parameters and verified by sublethal responses in tadpoles (i.e., feeding rate, feces production, growth, and fatty acid composition). Fungicides changed the nutritious quality of leaf litter likely through alterations in leaves’ neutral lipid fatty acid profiles (i.e., changes in some physiologically important highly unsaturated fatty acids reached more than 200%) in combination with a potential adsorption onto leaves during conditioning. These changes were reflected by differences in the development of tadpoles ultimately resulting in an earlier start of metamorphosis. Our data provide a first indication that fungicides potentially affect tadpole development indirectly through bottom‐up effects. This pathway is so far not addressed in fungicide environmental risk assessment and merits further attention. 相似文献
994.
《Saudi Journal of Biological Sciences》2023,30(1):103497
Agricultural crops especially fruit trees are constrained by edaphic stresses in shallow soils with low water retention and poor fertility. Therefore, interventions of shifting to trench planting for better root anchorage and replacing the filling soil were evaluated for 8 years in dragon fruit (Hylocereus undatus) cultivated in Deccan Plateau of peninsular India. When averaged for last 5-years, 44 % higher fruit yield (18.2 ± 1.0 Mg ha?1) was harvested from trees planted in trenches filled with 1:1 mixture (T-mixed) of native soil (loamy sand with 26.7 % stones (>2mm), field capacity, FC 0.20 cm3 cm?3; organic carbon, OC 0.17 %; Av-N 54.6 kg ha?1) and a black soil (clay 54.4 %; FC 0.42 cm3 cm?3; OC 0.70 %; Av-N 157.1 kg ha?1) than the recommended pit planting (12.4 ± 1.2 Mg ha?1). Improvements in fruit yields with trenches filled with black (T-black) and native (T-native) soil were 32 and 13 %, respectively. Yield losses (total– marketable yield) were reduced by 40, 20 and 18 % over pit method with T-mixed, T-black and T-native soil, respectively. Marketable quality attributes like fruit weight, fruit size metrics and pulp/peel content were further improved under T-mixed soil. Accumulation of total soluble solids (TSS), sugar content, phenolic and flavonoid compounds were higher in fruits from T-native soil. During storage, fruits from T-native soil and pit planting exhibited minimum physiological weight loss and retained more firmness, TSS, sugars, titratable acidity, phenolic-flavonoids contents, FARP and DPPH activities. T-mixed soil provided better hydrozone and nutrients for resilience of fruit plants while protecting from aeration problems envisaged in poorly drained black soils. With B:C ratio (1.85) and lower payback period (4-years), T-mixed soil showed superior economic viability. Therefore, soil management module of planting in trenches filled-in with mixture of native and black soils can be recommended to boost productivity of fruits from shallow soils under water scarce degraded regions without penalising agro-ecosystem. 相似文献
995.
Virginie Hutsemékers Lea Mouton Hannah Westenbohm Flavien Collart Alain Vanderpoorten 《Global Change Biology》2023,29(14):3990-4000
At the interface between atmosphere and vegetation, epiphytic floras have been largely used as indicators of air quality. The recovery of epiphytes from high levels of SO2 pollution has resulted in major range changes, whose interpretation has, however, been challenged by concomitant variation in other pollutants as well as climate change. Here, we combine historical and contemporary information on epiphytic bryophyte species distributions, climatic conditions, and pollution loads since the 1980s in southern Belgium to disentangle the relative impact of climate change and air pollution on temporal shifts in species composition. The relationship between the temporal variation of species composition, climatic conditions, SO2, NO2, O3, and fine particle concentrations, was analyzed by variation partitioning. The temporal shift in species composition was such, that it was, on average, more than twice larger than the change in species composition observed today among communities scattered across the study area. The main driver, contributing to 38% of this temporal shift in species composition, was the variation of air quality. Climate change alone did not contribute to the substantial compositional shifts in epiphytic bryophyte communities in the course of the last 40 years. As a consequence of the substantial drop of N and S loads over the last decades, present-day variations of epiphytic floras were, however, better explained by the spatial variation of climatic conditions than by extant pollution loads. The lack of any signature of recolonization delays of formerly polluted areas in the composition of modern floras suggests that epiphytic bryophytes efficiently disperse at the landscape scale. We suggest that a monitoring of epiphyte communities at 10-year intervals would be desirable to assess the impact of raising pollution sources, and especially pesticides, whose impact on bryophytes remains poorly documented. 相似文献
996.
Yanping Wang Zixia Wang Jingjing Zhang Huaqiao Yu Yan Chen Yingrui Gao Xiaodong Li Wen Li Fangdi Hu 《化学与生物多样性》2023,20(6):e202201108
The quality of traditional Chinese medicines (TCM) has a significant correlation with the source and growth years. However, there is no research on the relationship between the growth period and the quality of Codonopsis Radix (CR). This work aims to evaluate the quality of CR in different growth years (2–5 years). First, the content of 6 efficacy-related and 28 nutrient-related components in different growth years of CR was analyzed. The results showed that with the increase in growth years of CR, the content of some components increased, while some decreased. Then, the AHP-CRITIC method was performed to score the CR in different growth years, the results showed that the comprehensive score of CR increased with the increase of growth years, and the 5-year-CR had the highest score. Finally, in vitro activity assays were designed to verify the evaluation results. The results demonstrated that with the increase of growth years, the spleen lymphocyte proliferation activity and DPPH free radical scavenging activity of CR were enhanced, which proved that the AHP-CRITIC method is reasonable to evaluate the quality of CR in different growth years. The aforementioned findings demonstrated that CR quality improved with longer planting years. 相似文献
997.
998.
Summary Host selection by phytophagous insects is generally thought to be based on chemical or nutritional characteristics of the host. This is especially true for monophagous insects. However, many other factors may influence host choice. The present study examines host selection by Drosophila magnaquinaria, whose sole host is the yellow skunk cabbage, Lysichitum americanum. Utilization of skunk cabbage was tested relative to a set of alternative hosts. In the pre-alighting stage of host selection, skunk cabbage was found to be less attractive than tomato, cucumber, and commercial mushrooms. In pairwise oviposition tests, there were no differences among hosts. There were no differences in larval survivorship among skunk cabbage, tomato, cucumber, or Ramaria, and larvae developed into pupae earlier on tomato than on skunk cabbage. These results indicate that this monophagy is not based on characteristics of the host. We suggest that habitat selection is the more important factor in determining the association between D. magnaquinaria and skunk cabbage. 相似文献
999.
Taxonomy is a traditional subject, but it still receives attention and has become a topic of much discussion in recent years. Many of these discussions have raised concerns about the future of taxonomy, especially with regard to the workforce responsible for the discovery of new species in the context of declining biodiversity. Previous discussions were based on the taxonomic data of plants and animals, but the status of fungal taxonomy has not been mentioned. Fungi have one of the highest levels of biodiversity among all living organisms, second only to insects. The discussion of the future of taxonomy without the inclusion of fungal data is incomplete. Here, we present the results of analyses based on all new fungal taxa published since 1753. Fungal taxonomy is an ever‐growing area of study with increasing numbers of new taxa being described and growing numbers of fungal taxonomists. Compared with plants and most animal groups, there has been a much sharper increase in the rate at which new fungal taxa are being described. Furthermore, the number of taxonomists studying fungi has increased at a faster speed than those studying plants or animals. This indicates that fungal taxonomy is a prosperous subject and a dynamic area for scientific studies, and that it deserves much more attention and support. The study of fungal taxonomy will deepen our understanding of the biodiversity of our planet. 相似文献
1000.
Mark Deakin Steve Curwell Patrizia Lombardi 《The International Journal of Life Cycle Assessment》2001,6(6):373-383
This paper has outlined the areas of the Environment and Climate Programme (Economic and Social Aspects of Human Settlement)
the BEQUEST project addresses. It has also examined the framework for analysis the project sets out for a common understanding
of SUD and the assessment methods currently made use of by planners, architects, engineers and surveyors to build environmental
capacity. The paper has done this by:
相似文献
• | fore-grounding the question of urban development and representing the process of urbanisation as a life cycle of inter-related activities; |
• | agreeing the sustainable development issues underlying the urban process; |
• | identifying the environmental, economic and social structure, spatial level and time scales of sustainable urban development. |