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61.
We investigated whether the link between family-of-origin socioeconomic status (SES) and civic engagement in young adulthood is mediated by youth’s work values, that is, the desired characteristics of their current or future jobs. We used data from a Finnish study: 2004 (age 16–18, NT1?=?1,301); 2011 (age 23–25, NT2?=?1,096); and 2014 (age 25–27, NT3?=?1,138). A higher family SES in 2004 predicted youth’s higher civic engagement in 2014. A higher family SES also predicted a lower importance of extrinsic job rewards (e.g., good pay) in 2011, but it was unrelated to the importance of intrinsic job rewards (e.g., learning opportunities). Extrinsic work values, in turn, predicted lower civic engagement in 2014, above and beyond sociodemographic and personality characteristics. Intrinsic work values predicted higher civic engagement. Thus, extrinsic, but not intrinsic, work values partly mediated the link between family SES and youth civic engagement.  相似文献   
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Perry  CT  Kench  PS  Smithers  SG  Riegl  BR  Gulliver  P  Daniells  JJ 《Coral reefs (Online)》2017,36(3):1013-1021

Low-lying coral reef islands are considered highly vulnerable to climate change, necessitating an improved understanding of when and why they form, and how the timing of formation varies within and among regions. Several testable models have been proposed that explain inter-regional variability as a function of sea-level history and, more recently, a reef platform size model has been proposed from the Maldives (central Indian Ocean) to explain intra-regional (intra-atoll) variability. Here we present chronostratigraphic data from Pipon Island, northern Great Barrier Reef (GBR), enabling us to test the applicability of existing regional island evolution models, and the platform size control hypothesis in a Pacific context. We show that reef platform infilling occurred rapidly (~4–5 mm yr−1) under a “bucket-fill” type scenario. Unusually, this infilling was dominated by terrigenous sedimentation, with platform filling and subsequent reef flat formation complete by ~5000 calibrated years BP (cal BP). Reef flat exposure as sea levels slowly fell post highstand facilitated a shift towards intertidal and subaerial-dominated sedimentation. Our data suggest, however, a lag of ~1500 yr before island initiation (at ~3200 cal BP), i.e. later than that reported from smaller and more evolutionarily mature reef platforms in the region. Our data thus support: (1) the hypothesis that platform size acts to influence the timing of platform filling and subsequent island development at intra-regional scales; and (2) the hypothesis that the low wooded islands of the northern GBR conform to a model of island formation above an elevated reef flat under falling sea levels.

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In this report, the strategy and outcome of expanding SAR exploration to improve solubility and metabolic stability are discussed. Compound 35 exhibited excellent potency, selectivity over A(1) and improved solubility of >4 mg/mL at pH 8.0. In addition, compound 35 had good metabolic stability with a scaled intrinsic clearance of 3 mL/min/kg (HLM) and demonstrated efficacy in the haloperidol induced catalepsy model.  相似文献   
66.
A major limitation in studying molecular interactions between parasitic helminths and their hosts is the lack of suitable in vitro cultivation systems for helminth cells and larvae. Here we present a method for long-term in vitro cultivation of larval cells of the tapeworm Echinococcus multilocularis, the causative agent of alveolar echinococcosis. Primary cells isolated from cultivated metacestode vesicles in vitro showed a morphology typical of Echinococcus germinal cells, displayed an Echinococcus-specific gene expression profile and a cestode-like DNA content of approximately 300Mbp. When kept under reducing conditions in the presence of Echinococcus vesicle fluid, the primary cells could be maintained in vitro for several months and proliferated. Most interestingly, upon co-cultivation with host hepatocytes in a trans-well system, mitotically active Echinococcus cells formed cell aggregates that subsequently developed central cavities, surrounded by germinal cells. After 4 weeks, the cell aggregates gave rise to young metacestode vesicles lacking an outer laminated layer. This layer was formed after 6 weeks of cultivation indicating the complete in vitro regeneration of metacestode larvae. As an initial step toward the creation of a fully transgenic strain, we carried out transient transfection of Echinococcus primary cells using plasmids and obtained heterologous expression of a reporter gene. Furthermore, we successfully carried out targeted infection of Echinococcus cells with the facultatively intracellular bacterium Listeria monocytogenes, a DNA delivery system for genetic manipulation of mammalian cells. Taken together, the methods presented herein constitute important new tools for molecular investigations on host-parasite interactions in alveolar echinococcosis and on the roles of totipotent germinal cells in parasite regeneration and metastasis formation. Moreover, they enable the development of fully transgenic techniques in this group of helminth parasites for the first time.  相似文献   
67.
The protein kinase Mps1 is, among others, essential for the spindle assembly checkpoint (SAC). We found that Saccharomyces cerevisiae Mps1 interacts physically with the N-terminal domain of Ndc80 (Ndc801−257), a constituent of the Ndc80 kinetochore complex. Furthermore, Mps1 effectively phosphorylates Ndc801−257 in vitro and facilitates Ndc80 phosphorylation in vivo. Mutating 14 of the phosphorylation sites to alanine results in compromised checkpoint signalling upon nocodazole treatment of mutants. Mutating the identical sites to aspartate (to simulate constitutive phosphorylation) causes a metaphase arrest with wild-type-like bipolar kinetochore–microtubule attachment. This arrest is due to a constitutively active SAC and consequently the inviable aspartate mutant can be rescued by disrupting SAC signalling. Therefore, we conclude that a putative Mps1-dependent phosphorylation of Ndc80 is important for SAC activation at kinetochores.  相似文献   
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69.

Background  

Among the members of the genus Bordetella B. petrii is unique, since it is the only species isolated from the environment, while the pathogenic Bordetellae are obligately associated with host organisms. Another feature distinguishing B. petrii from the other sequenced Bordetellae is the presence of a large number of mobile genetic elements including several large genomic regions with typical characteristics of genomic islands collectively known as integrative and conjugative elements (ICEs). These elements mainly encode accessory metabolic factors enabling this bacterium to grow on a large repertoire of aromatic compounds.  相似文献   
70.
Fibroblast growth factor 2 (FGF2) is a potent mitogen that is exported from cells by an endoplasmic reticulum (ER)/Golgi‐independent mechanism. Unconventional secretion of FGF2 occurs by direct translocation across plasma membranes, a process that depends on the phosphoinositide phosphatidylinositol 4,5‐biphosphate (PI(4,5)P2) at the inner leaflet as well as heparan sulfate proteoglycans at the outer leaflet of plasma membranes; however, additional core and regulatory components of the FGF2 export machinery have remained elusive. Here, using a highly effective RNAi screening approach, we discovered Tec kinase as a novel factor involved in unconventional secretion of FGF2. Tec kinase does not affect FGF2 secretion by an indirect mechanism, but rather forms a heterodimeric complex with FGF2 resulting in phosphorylation of FGF2 at tyrosine 82, a post‐translational modification shown to be essential for FGF2 membrane translocation to cell surfaces. Our findings suggest a crucial role for Tec kinase in regulating FGF2 secretion under various physiological conditions and, therefore, provide a new perspective for the development of a novel class of antiangiogenic drugs targeting the formation of the FGF2/Tec complex.  相似文献   
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