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1.
Geek culture is a subculture of enthusiasts that is traditionally associated with obscure media (Japanese animation, science fiction, video games, etc.). However, geek culture is becoming increasingly mainstream; for example, in the past year alone, Dragon*Con, a major Geek convention in Atlanta, Georgia, attracted an attendance of over 57,000 members. The present article uses an individual differences approach to examine three theoretical accounts of geek culture. Seven studies (N = 2354) develop the Geek Culture Engagement Scale (GCES) to quantify geek engagement and assess its relationships to theoretically relevant personality and individual differences variables. These studies present evidence that individuals may engage in geek culture in order to maintain narcissistic self-views (the great fantasy migration hypothesis), to fulfill belongingness needs (the belongingness hypothesis), and to satisfy needs for creative expression (the need for engagement hypothesis). Geek engagement is found to be associated with elevated grandiose narcissism, extraversion, openness to experience, depression, and subjective well-being across multiple samples. These data lay the groundwork for further exploration of geek culture as well as provide a foundation for examining other forms of subculture participation. 相似文献
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Does a long‐term shift in Wood Stork diet foreshadow adaptability to human‐induced rapid environmental change? 下载免费PDF全文
To preserve biodiversity, identifying at‐risk populations and developing conservation plans to mitigate the effects of human‐induced rapid environmental change (HIREC) are essential. Changes in diet, especially for food‐limited species, can aid in detecting populations being impacted by HIREC, and characterizing the quality, abundance, and temporal and spatial consistency of newly consumed food items may provide insight concerning the likelihood of a species persisting in a changing environment. We used Wood Storks (Mycteria americana) nesting in the Florida Everglades as a model system to study the possible effects of HIREC on a food‐limited population. We compared the diets of Wood Storks in 2013 and 2014 with those reported during the 1970s before major anthropogenic activities affected the Everglades system and prey availability. Wood Storks in our study consumed more large‐bodied sunfish species (Lepomis spp.), fewer native marsh fishes, and more non‐native fish species than during the 1970s. Large sunfish and non‐native fish are relatively rare in the drying pools of Everglades marshes where storks traditionally forage, suggesting that Wood Storks may be using novel foraging habitats such as created wetlands (i.e., canals and stormwater ponds). Although created wetlands have long hydroperiods conducive to maintaining large‐bodied fishes and could provide alternative foraging habitat when prey availability is reduced in natural marshes, additional studies are needed to determine the extent to which these wetlands are used by Wood Storks and, importantly, the quality of prey items potentially available to foraging Wood Storks in created wetlands. 相似文献
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Jessica Hanser 《Curtis's Botanical Magazine》2017,34(4):314-322
This essay reveals a financial dimension to Captain John Blake and his son John Bradby Blake's involvement with China, namely, their participation in financing the Canton trade through predatory loans to Chinese Hong merchants. Widespread predatory lending in Canton led to a financial crisis during the late 1770s, which ruined several British and Chinese merchants. In an effort to recover the money they claimed was owed to them, many British traders, including John Blake, formed a lobby group in London and authorized Britain's first Ambassador to China to negotiate with the Emperor in Beijing on their behalf. 相似文献
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A detailed morphological staging system for cattle embryos at stages following blastocyst hatching and preceding gastrulation is presented here together with spatiotemporal mapping of gene expression for BMP4, BRACHYURY, CERBERUS1 (CER1), CRIPTO, EOMESODERMIN, FURIN and NODAL. Five stages are defined based on distinct developmental events. The first of these is the differentiation of the visceral hypoblast underlying the epiblast, from the parietal hypoblast underlying the mural trophoblast. The second concerns the formation of an asymmetrically positioned, morphologically recognisable region within the visceral hypoblast that is marked by the presence of CER1 and absence of BMP4 expression. We have termed this the anterior visceral hypoblast or AVH. Intra-epiblast cavity formation and the disappearance of the polar trophoblast overlying the epiblast (Rauber’s layer) have been mapped in relation to AVH formation. The third chronological event involves the transition of the epiblast into the embryonic ectoderm with concomitant onset of posterior NODAL, EOMES and BRACHYURY expression. Lastly, gastrulation commences as the posterior medial embryonic ectoderm layer thickens to form the primitive streak and cells ingress between the embryonic ectoderm and hypoblast. At this stage a novel domain of CER1 expression is seen whereas the AVH disappears. Comparison with the mouse reveals that while gene expression patterns at the onset of gastrulation are well conserved, asymmetry establishment, which relies on extraembryonic tissues such as the hypoblast and trophoblast, has diverged in terms of both gene expression and morphology. 相似文献
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Cao Dinh Hung Chang-Hee Hong Seon-Ki Kim Kyu-Han Lee Jea-Young Park Min-Woo Nam Dae-Ho Choi Hye-In Lee 《Acta Physiologiae Plantarum》2016,38(6):152
Light-emitting diodes (LEDs) are useful for the growth of many plants, but not known for blueberry species. This study examined the effects of fluorescent lamps and 100 % red, 80 % red plus 20 % blue, 50 % red plus 50 % blue, and 100 % blue LEDs on the growth and development of highbush blueberry shoots under aseptic and non-aseptic conditions. Results revealed that monochromatic blue LEDs accumulated the highest contents of leaf chlorophylls. In contrast, monochromatic red LEDs inhibited chlorophyll accumulation, but produced the longest shoots and roots and provided high percentages of side shoot formation from ex vitro plants. Mixed LEDs, particularly 50 % red plus 50 % blue light, improved plant growth with respect to notably increased shoot and root biomass. Direct rooting of in vitro shoots under non-aseptic conditions was readily achieved using a commercial mixture of perlite and peat moss with high humidity controls. These findings obviously suggest the efficient use of LEDs to replace traditional fluorescent lamps in large-scale propagation of the highbush blueberry, and also pave the way for future studies on LEDs for standardizing micropropagation protocols to shrub crops and woody plants. 相似文献
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S.C. Hung N.I. Ghali D.L. Venton G.C. Le Breton 《Prostaglandins & other lipid mediators》1982,24(2):195-206
The effects of prostaglandin F2α on human blood platelet function were investigated. PGF2α at 15 μM completely blocked platelet aggregation induced by 500 μM arachidonic acid or 3 μM U46619 but had no effect on aggregatin induced by 7.5 μM ADP. A similar specificity of action was not obtained with either PGI2 or PGE2. Thus concentrations of PGI2 (3 nM) or PGE2 (20 μ M) which inhibited U46619-induced aggregation by 100% also blocked ADP-stimulated aggregation.The inhibitory properties of PGF2α were not related to increases in platelet cAMP, since direct measurement of intracellular cAMP revealed that 15 μ M PGF2α produced no substantial change in cAMP levels. This finding was in direct contrast to results obtained using either PGI2 or PGE2. Both PGI2 (3 nM) and PGE2 (20 μ M) induced significant increases in platelet cAMP levels.The possibility that PGF2α directly interacts at the platelet TXA2/PGH2 receptor was investigated by measuring [3H]PGF2α binding to isolated platelet membranes. It was found that [3H] PGF2α binding reached equilibrium within 30 min at room temperature and could be 90% displaced by addition of 1000 fold excess of unlabelled PGF2α. Furthermore, when 1000 fold excess of either the TXA2/PGH2 “mimetic” U46619 or the TXA2/PGH2 antagonist 13-azaprostanoic acid was added, specific [3H] PGF2α binding was displaced by 95% and 85% respectively. In contrast, the same molar excess of 6-keto-PGF1α, azo analog 1, or TXB2, caused displacement of only 15%, 20% or 25% of the [3H] PGF2α binding. Scatchard analysis indicated that [3H] PGF2α has two binding sites; i.e., a high affinity binding site with an apparent Kd of 50 nM and a low affinity binding site with apparent Kd of 320 nM. These results suggest that the selective inhibition by PGF2α of AA or U46619-induced aggregation may be mediated through interaction at the platelet TXA2/PGH2 receptor. 相似文献
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