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Controlling the energetics and backbone order of semiconducting polymers is essential for the performance improvement of polymer‐based solar cells. The use of fluorine as the substituent for the backbone is known to effectively deepen the molecular orbital energy levels and coplanarize the backbone by noncovalent interactions with sulfur of the thiophene ring. In this work, novel semiconducting polymers are designed and synthesized based on difluoronaphthobisthiadiazole (FNTz) as a new family of naphthobisthiadiazole (NTz)–quaterthiophene copolymer systems, which are one of the highest performing polymers in solar cells. The effect of the fluorination position on the energetics and backbone order is systematically studied. It is found that the dependence of the solar cell fill factor on the active layer thickness is very sensitive to the fluorination position. It is thus further investigated and discussed how the structural features of the polymers influence the photovoltaic parameters as well as the diode characteristics and bimolecular recombination. Further, the polymer with fluorine on both the naphthobisthiadiazole and quaterthiophene moieties exhibits a quite high power conversion efficiency of 10.8% in solar cells in combination with a fullerene. It is believed that the results would offer new insights into the development of semiconducting polymers.  相似文献   
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Endometrial cancer is the most common gynecologic malignancy and is associated with increased morbidity each year, including young people. However, its mechanisms of proliferation and progression are not fully elucidated. It is well known that abnormal glycosylation is involved in oncogenesis, and fucosylation is one of the most important types of glycosylation. In particular, fucosyltransferase 8 (FUT8) is the only FUT responsible for α1, 6-linked fucosylation (core fucosylation), and it is involved in various physiological as well as pathophysiological processes, including cancer biology. Therefore, we aimed to identify the expression of FUT8 in endometrial endometrioid carcinoma and investigate the effect of the partial silencing of the FUT8 gene on the cell proliferation of Ishikawa cells, an epithelial-like endometrial cancer cell line. Quantitative real-time PCR analysis showed that FUT8 gene expression was significantly elevated in the endometrial endometrioid carcinoma, compared to the normal endometrium. The immunostaining of FUT8 and Ulex europaeus Agglutinin 1 (UEA-1), a kind of lectin family specifically binding to fucose, was detected endometrial endometrioid carcinoma. The proliferation assay showed FUT8 partial knockdown by transfection of siRNA significantly suppressed the proliferation of Ishikawa cells, concomitant with the upregulation in the gene expressions associated with the interesting pathways associated with de-ubiquitination, aspirin trigger, mesenchymal-epithelial transition (MET) et al. It was suggested that the core fucosylation brought about by FUT8 might be involved in the proliferation of endometrial endometrioid carcinoma cells.  相似文献   
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Although the unique organization of vertebrate cone mosaics was first described long ago,both their underlying molecular basis and physiological significance are largely unknown.Here,we demonstrate that Crumbs proteins,the key regulators of epithelial apical polarity,establish the planar cellular polarity of photoreceptors in zebrafish.Via heterophilic Crb2a-Crb2b interactions,the apicobasal polarity protein Crb2b restricts the asymmetric planar distribution of Crb2a in photoreceptors.The planar polarized Crumbs proteins thus balance intercellular adhesions and tension between photoreceptors,thereby stabilizing the geometric organization of cone mosaics.Notably,loss of Crb2b in zebrafish induces a nearsightedness-like phenotype in zebrafish accompanied by an elongated eye axis and impairs zebrafish visual perception for predation.These data reveal a detailed mechanism for cone mosaic homeostasis via previously undiscovered apical-planar polarity coordination and propose a pathogenic mechanism for nearsightedness.  相似文献   
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Landscape and Ecological Engineering - There have been many earlier studies of the biodiversity and ecosystem services of abandoned farmlands, but studies of abandoned villages are limited,...  相似文献   
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High-temperature-mediated adaptation in plant architecture is linked to the increased synthesis of the phytohormone auxin, which alters cellular auxin homeostasis. The auxin gradient, modulated by cellular auxin homeostasis, plays an important role in regulating the developmental fate of plant organs. Although the signaling mechanism that integrates auxin and high temperature is relatively well understood, the cellular auxin homeostasis mechanism under high temperature is largely unknown. Using the Arabidopsis thaliana root as a model, we demonstrate that under high temperature, roots counterbalance the elevated level of intracellular auxin by promoting shootward auxin efflux in a PIN-FORMED2 (PIN2)-dependent manner. Further analyses revealed that high temperature selectively promotes the retrieval of PIN2 from late endosomes and sorts them to the plasma membrane through an endosomal trafficking pathway dependent on SORTING NEXIN1. Our results demonstrate that recycling endosomal pathway plays an important role in facilitating plants adaptation to increased temperature.  相似文献   
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Arylamine N-acetyltransferase (NAT) genes in humans and in rodents encode polymorphic drug metabolizing enzymes. Human NAT1 (and the murine equivalent mouse Nat2) is found early in embryonic development and is likely to have an endogenous role. We report the detailed expression of the murine gene (Nat2) and encoded protein in mouse embryos, using a transgenic mouse model bearing a lacZ transgene inserted into the coding region of mouse Nat2. In mouse embryos, the transgene was expressed in sensory epithelia, epithelial placodes giving rise to visceral sensory neurons, the developing pituitary gland, sympathetic chain and urogenital ridge. In Nat2+/+ mice, the presence and activity of Nat2 protein was detected in these tissues and their adult counterparts. Altered expression of the human orthologue in breast tumours, in which there is endocrine signalling, suggests that human NAT1 should be considered as a potential biomarker for neuroendocrine tissues and tumours.  相似文献   
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Background

Whereas estrogen receptors are present in immune cells, it is not known if they are phosphorylated to regulate immune cell functions. Here we determined the phosphorylation status of estrogen receptor α (ERα) at residue serine 216 in mouse neutrophils and examined its role in migration and infiltration. Serine 216 is the conserved phosphorylation site within the DNA binding domains found in the majority of nuclear receptors.

Methodology/Principal Findings

A phospho-peptide antibody specific to phosphorylated serine 216 and ERα KO mice were utilized in immunohistochemistry, double immuno-staining or Western blot to detect phosphorylation of ERα in peripheral blood as well as infiltrating neutrophils in the mouse uterus. Transwell assays were performed to examine migration of neutrophils. An anti-Ly6G antibody identified neutrophils. About 20% of neutrophils expressed phosphorylated ERα at serine 216 in peripheral white blood cells (WBC) from C3H/HeNCrIBR females. Phosphorylation was additively segregated between C3H/HeNCrIBR and C57BL/6 females. Only neutrophils that expressed phosphorylated ERα migrated in Transwell assays as well as infiltrated the mouse uterus during normal estrous cycles.

Conclusions/Significance

ERα was phosphorylated at serine 216 in about 20% of mouse peripheral blood neutrophils. Only those that express phosphorylated ERα migrate and infiltrate the mouse uterus. This phosphorylation was the first to be characterized in endogenous ERα found in normal tissues and cells. Phosphorylated ERα may have opened a novel research direction for biological roles of phosphorylation in ERα actions and can be developed as a drug target for treatment of immune-related diseases.  相似文献   
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