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121.
Identifying Drivers of China's Provincial Wastewater Reuse Outcomes Using Qualitative Comparative Analysis 下载免费PDF全文
In water‐scarce regions of China, wastewater reuse is increasingly considered as a potential component of China's future water resource management strategy. Currently, the percentage of wastewater reuse varies substantially across Chinese provinces, but conditions leading to a high rate of wastewater reuse have not been elucidated clearly. In this work, we use fuzzy‐set qualitative comparative analysis (fsQCA) to identify the drivers of high and low percentages of wastewater reuse in water‐stressed Chinese provinces in 2013. We find that among the five conditions studied (per capita water availability, urban population, access to sea, access to urban space, and access to agricultural land), a high percentage of wastewater reuse is primarily driven by water stress and access to urban green space. Consequently, policies should consider targeting provinces with these attributes where wastewater reuse is more likely to be successful. Further, our results show that there is asymmetry in the conditions that lead to high and low percentages of wastewater reuse, and that the drivers for and against reuse identified in this study are not completely analogous to those identified in previous studies. As such, the drivers for and against wastewater reuse should not be generalized without due consideration of the local context. 相似文献
122.
Felicitas Boretti Caterina Musella Wanda Burkhardt Claudia Kuemmerle-Fraune Barbara Riond Claudia Reusch Nadja Sieber-Ruckstuhl 《BMC veterinary research》2018,14(1):417
Background
The ideal method for monitoring trilostane therapy in dogs with hypercortisolism is still open to debate. Recently, determination of the pre-trilostane (prepill) cortisol concentration has been proposed to be more repeatable than either post-trilostane or post-ACTH cortisol. The aim of this study was to compare two prepill cortisol concentrations in dogs with hypercortisolism during trilostane therapy. Sixteen client-owned dogs with naturally occurring hypercortisolism were prospectively included and cortisol concentrations were measured twice, 1?h apart, before the morning trilostane dose (prepill 1 and 2 cortisol).Results
A total of 47 prepill cortisol measurement pairs were included. Compared to prepill 1, prepill 2 cortisol was higher in 15, equal in 8 and lower in 24 pairs. Group agreement between prepill 1 and 2 cortisol was 70% (moderate agreement - weighted kappa 0.55). In 30% of the pairs, group assignment was discrepant, implying a different therapeutic decision. In some dogs certain circumstances (e.g. excessive barking, difficulties during blood collection, excitement at arrival) were identified as potential factors explaining the discrepancy between prepill 1 and 2 cortisol measurements.Conclusions
In a substantial number of dogs treated with trilostane, the two prepill cortisol concentrations differed. Part of this difference might be ascribable to stressful events during test performance. When using prepill cortisol measurements to monitor trilostane therapy, recording of any incident during handling that might affect cortisol release might be helpful to make a reliable decision about a trilostane dose adaptation.123.
Capsule: Nocturnal passerine migration patterns were studied by a network of weather radars within the East-Atlantic flyway providing large-scale information on the effect of a geographical barrier.Aims: The aim of this study was to obtain a large-scale spatial overview of the effects of a sea barrier on migratory flyways in northern Spain/western France.Methods: Weather radar data were used from five sites at the Bay of Biscay during nights in spring 2015 to calculate flight directions and migration traffic rates (MTRs).Results: The highest MTRs were registered by the radars at the southeastern edge of the bay, with a gradual decrease northwards. Spring migration direction was generally NNE/NE. Continuous nocturnal migration pattern indicated migration over land in the south. The radar half way up the French coast exhibited bimodal migration intensities at night, indicating sea crossing, and the northernmost corner of the bay showed little migration.Conclusions: Radar patterns indicated migration over land and sea during spring migration. Sea crossing occurred with flight distances of up to about 500?km. Most migration activity was observed in the radars along the southeastern section of the bay, indicating that the general migration flyway from Spain funnels through the eastern side of the north Iberian Peninsula. 相似文献
124.
125.
Destruction of low efficiency markers is a slow process occurring at a heteroduplex stage of transformation 总被引:51,自引:0,他引:51
Summary Direct evidence is presented that the mechanism which discriminates against low efficiency markers in transformation of Diplococcus pneumoniae of genotype hex
+ acts on them after the formation of donor-recipient heteroduplexes. This conclusion is based on assays of the transforming activity of donor markers in lysates made after various times of incubation of recipient cells following exposure to DNA. The activity of a low efficiency marker rises substantially, indicating formation of native-like heteroduplex structures, and then falls. At 37° C the process is essentially completed 10 minutes after entry, and the apparent half life of a susceptible heteroduplex is 1.5 to 2 minutes. Data from these and other experiments imply that about as many of the surviving low efficiency markers have simply escaped attack as have been inserted into both strands by the excision-repair process suggested by Ephrussi-Taylor. 相似文献
126.
T4 DNA polymerase strongly influences the frequency and specificity of frameshift mutagenesis. Fifteen of 19 temperature-sensitive alleles of the DNA polymerase gene substantially influenced the reversion frequencies of frameshift mutations measured in the T4 rII genes. Most polymerase mutants increased frameshift frequencies, but a few alleles (previously noted as antimutators for base substitution mutations) decreased the frequencies of certain frameshifts while increasing the frequencies of others. The various patterns of enhanced or decreased frameshift mutation frequencies suggest that T4 DNA polymerase is likely to play a variety of roles in the metabolic events leading to frameshift mutation. A detailed genetic study of the specificity of the mutator properties of three DNA polymerase alleles (tsL56, tsL98 and tsL88) demonstrated that each produces a distinctive frameshift spectrum. Differences in frameshift frequencies at similar DNA sequences within the rII genes, the influence of mutant polymerase alleles on these frequencies, and the presence or absence of the dinucleotide sequence associated with initiation of Okazaki pieces at the frameshift site has led us to suggest that the discontinuities associated with discontinuous DNA replication may contribute to spontaneous frameshift mutation frequencies in T4. 相似文献
127.
128.
For trees in tropical forests, competition for light is thought to be a central process that offers opportunities for niche differentiation through light gradient partitioning. In previous studies, a canopy index based on three-dimensional canopy census data has been shown to be a good predictor of species-specific demographic rates across the entire tree community on Barro Colorado Island, Panama, and has allowed quantifying between-species variation in light response. However, almost all other forest census plots lack data on the canopy structure. Hence, this study aims at assessing whether position-based neighborhood competition indices can replace information from canopy census data and produce similar estimates of the interspecific variation of light responses. We used inventory data from the census plot at Barro Colorado Island and calculated neighborhood competition indices with varying relative effects of the size and distance of neighboring trees. Among these indices, we selected the one that was most strongly correlated with the canopy index. We then compared outcomes of hierarchical Bayesian models for species-specific recruitment and growth rates including either the canopy index or the selected neighborhood competition index as predictor. Mean posterior estimates of light response parameters were highly correlated between models (r>0.85) and indicated that most species regenerate and grow better in higher light. Both light estimation approaches consistently found that the interspecific variation of light response was larger for recruitment than for growth rates. However, the classification of species into different groups of light response, e.g. weaker than linear (decelerating) vs. stronger than linear (accelerating) differed between approaches. These results imply that while the classification into light response groups might be biased when using neighborhood competition indices, they may be useful for determining species rankings and between-species variation of light response and therefore enable large comparative studies between different forest census plots. 相似文献
129.
130.
Giardia lamblia: detection and characterization of calmodulin 总被引:1,自引:0,他引:1
M L Munoz E C Weinbach S C Wieder C E Claggett L Levenbook 《Experimental parasitology》1987,63(1):42-48
Calmodulin was detected in Giardia lamblia by radioimmunoassay and cyclic AMP phosphodiesterase activation. This protein was purified to apparent homogeneity by fast protein liquid chromatography with a yield of 260 ng of calmodulin/mg of protozoan protein. Purity was established by gel electrophoresis, gel filtration, and ion exchange chromatography. The parasite calmodulin has properties characteristic of calmodulin isolated from other eukaryotes, e.g., an apparent molecular weight of 16.7 kD; activation in calcium dependent manner of bovine heart cyclic nucleotide phosphodiesterase; and sensitivity to known calmodulin antagonists. 相似文献