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11.
12.
Taurine as a possible inhibitory transmitter in the cerebellum 总被引:6,自引:0,他引:6
13.
14.
The temporal availability of propagules is a critical factor in sustaining pioneer riparian tree populations along snowmelt-driven
rivers because seedling establishment is strongly linked to seasonal hydrology. River regulation in semi-arid regions threatens
to decouple seed development and dispersal from the discharge regime to which they evolved. Using the lower Tuolumne River
as a model system, we quantified and modeled propagule availability for Populus fremontii (POFR), Salix gooddingii (SAGO), and Salix exigua (SAEX), the tree and shrub species that dominate near-channel riparian stands in the San Joaquin Basin, CA. A degree-day
model was fit to field data of seasonal seed density and local temperature from three sites in 2002–2004 to predict the onset
of the peak dispersal period. To evaluate historical synchrony of seed dispersal and seasonal river hydrology, we compared
peak spring runoff timing to modeled peak seed release periods for the last 75 years. The peak seed release period began on
May 15 for POFR (range April 23–June 10), May 30 for SAGO (range May 19–June 11) and May 31 for SAEX (range May 8–June 30).
Degree-day models for the onset of seed release reduced prediction error by 40–67% over day-of-year means; the models predicted
best the interannual, versus site-to-site, variation in timing. The historical analysis suggests that POFR seed release coincided
with peak runoff in almost all years, whereas SAGO and SAEX dispersal occurred during the spring flood recession. The degree-day
modeling approach reduce uncertainty in dispersal timing and shows potential for guiding flow releases on regulated rivers
to increase riparian tree recruitment at the lowest water cost. 相似文献
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Spores from four Frankia strains were isolated and purified to homogeneity. The purified spores were biochemically and physiologically characterized and compared to vegetative cells. Frankia spores exhibited low levels of endogenous respiration that were at least ten-fold lower than the endogenous respiration rate of vegetative cells. The macromolecular content of purified spores and vegetative cells differed. One striking difference among the Frankia spores was their total DNA content. From DAPI staining experiments, only 9% of strain ACN1AG spore population contained DNA. With strains DC12 and EuI1c, 92% and 67% of their spore population contained DNA. The efficiency of spore germination was correlated to the percentage of the spore population containing DNA. These results suggest that the majority of strain ACN1AG spores were immature or nonviable. The presence of a solidifying agent inhibited the initial stages of spore germination, but had no effect once the process had been initiated. The optimal incubation temperature for spore germination was 25°C and 30°C for strains DC12 and EuI1c, respectively. A mild heat shock increased the efficiency of spore germination, while root extracts also stimulated spore germination. These results suggest that strains DC12 and EuI1c may be suitable strains for further germination and genetic studies. 相似文献
17.
Marissa A. Dyck Ruben Iosif Barbara PrombergerFürpass Viorel D. Popescu 《Ecology and evolution》2022,12(5)
- The recovery of terrestrial carnivores in Europe is a conservation success story. Initiatives focused on restoring top predators require information on how resident species may interact with the re‐introduced species as their interactions have the potential to alter food webs, yet such data are scarce for Europe.
- In this study, we assessed patterns of occupancy and interactions between three carnivore species in the Romanian Carpathians. Romania houses one of the few intact carnivore guilds in Europe, making it an ideal system to assess intraguild interactions and serve as a guide for reintroductions elsewhere.
- We used camera trap data from two seasons in Transylvanian forests to assess occupancy and co‐occurrence of carnivores using multispecies occupancy models.
- Mean occupancy in the study area was highest for lynx (Ψwinter = 0.76 95% CI: 0.42–0.92; Ψautumn = 0.71 CI: 0.38–0.84) and wolf (Ψwinter = 0.60 CI: 0.34–0.78; Ψautumn = 0.81 CI: 0.25–0.95) and lowest for wildcat (Ψwinter = 0.40 CI: 0.19–0.63; Ψautumn = 0.52 CI: 0.17–0.78)
- We found that marginal occupancy predictors for carnivores varied between seasons. We also found differences in predictors of co‐occurrence between seasons for both lynx‐wolf and wildcat‐wolf co‐occurrence. For both seasons, we found that conditional occupancy probabilities of all three species were higher when another species was present.
- Our results indicate that while there are seasonal differences in predictors of occupancy and co‐occurrence of the three species, co‐occurrence in our study area is high.
- Terrestrial carnivore recovery efforts are ongoing worldwide. Insights into interspecific relations between carnivore species are critical when considering the depauperate communities they are introduced in. Our work showcases that apex carnivore coexistence is possible, but dependent on protection afforded to forest habitats and their prey base.
18.
B-cell receptor activation induces BIC/miR-155 expression through a conserved AP-1 element 总被引:3,自引:0,他引:3
Yin Q Wang X McBride J Fewell C Flemington E 《The Journal of biological chemistry》2008,283(5):2654-2662
19.
Zhe Nie Victoria Feher Srinivasa Natala Christopher McBride Andre Kiryanov Benjamin Jones Betty Lam Yan Liu Stephen Kaldor Jeffrey Stafford Kouki Hikami Noriko Uchiyama Tomohiro Kawamoto Yuichi Hikichi Shin-ichi Matsumoto Nobuyuki Amano Lilly Zhang David Hosfield Takashi Ichikawa 《Bioorganic & medicinal chemistry letters》2013,23(12):3662-3666
Using structure-based drug design, we identified and optimized a novel series of pyrimidodiazepinone PLK1 inhibitors resulting in the selection of the development candidate TAK-960. TAK-960 is currently undergoing Phase I evaluation in adult patients with advanced solid malignancies. 相似文献