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991.
Sei-Woong Choi 《Ecological Research》2016,31(3):321-331
We investigated elevational richness patterns of three moth groups (Erebidae, Geometridae, and Noctuidae) along four elevational gradients located on one northern and three southern mountains in South Korea, as well as the effects of plants and climatic factors on the diversity patterns of moths. Moths were collected with an ultraviolet light trap at 32 sites from May through October, 2013. Plant species richness and mean temperatures for January and June were acquired. Observed and estimated moth species richness was calculated and the diversity patterns with null models were compared. Species richness along four elevational gradients peaked at mid-elevations, whereas deviations occurred at elevations below mid-peak in the southern mountains and elevations higher than mid-peak on the northern mountain. Species richness curves of three moth groups also peaked at mid-elevations throughout South Korea. However, the species richness curves for Erebidae were positively skewed, indicating that a preference for lowlands, whereas curves of the Geometridae were negatively skewed, indicating a preference for highlands. The mid-peak diversity pattern between plants and moths on the Korean mountains showed an elevational breadth that overlapped between 800 and 900 m. Multiple regression analysis revealed that plant species richness and January mean temperature significantly influenced moth species richness and abundance. The rapid increase in mean annual temperature in the Korean peninsula and the unimodal elevational gradients of moths across the country suggest that an uphill shift in peak optimum elevation and changes in the highest peak of the curve will occur in the future. 相似文献
992.
To clarify the ploidy and distribution of Lilium leichtlinii var. maximowiczii populations in Korea, we inspected several mountains and northern valleys and almost all of the sea coast of South Korea. We found nine diploid populations and 19 triploid populations. Many large and small populations were distributed around northern Chungcheongbook‐do and Gyunggi‐do and all over Kangwon‐do. The diploid plants were smaller than the triploid plants in almost all of their morphological characteristics. This is the second report of natural polyploid complexes of diploids and triploids in the genus Lilium. 相似文献
993.
994.
Kyu‐Won Kwak Hong‐Soo Choi Sung‐Hee Nam Myung‐Sae Han Eunsun Kim Kwanho Park Heui‐Sam Lee 《Entomological Research》2019,49(12):534-538
This report reveals the structure of a virus extracted from the Korean horn beetle Allomyrina dichotoma. The purified virus particle was 100% identical to Allomyrina virus lef‐8 sequence registered as KM_233709.1. The structure of this virus was confirmed to be closely related to that of the Nudiviridae family, and it was rod shaped and enveloped, and observed to be of approximately the mean length of a single viral nucleocapsid of 200–210 nm and mean diameter of 100–110 nm. These results provide an insight into the structural characteristics of the Nudiviridae family that can be used for nudiviral identification. 相似文献
995.
The role of the hippocampus in social memory and behavior is under intense investigation. Oxytocin (Oxt) and vasopressin (Avp) are two neuropeptides with many central actions related to social cognition. Oxt‐ and Avp‐expressing fibers are abundant in the hippocampus and receptors for both peptides are seen throughout the different subfields, suggesting that Oxt and Avp modulate hippocampal‐dependent processes. In this review, we first focus on the anatomical sources of Oxt and Avp input to the hippocampus and consider the distribution of their corresponding receptors in different hippocampal subfields and neuronal populations. We next discuss the behavioral outcomes related to social memory seen with perturbation of hippocampal Oxt and Avp signaling. Finally, we review Oxt and Avp modulatory mechanisms in the hippocampus that may underlie the behavioral roles for both peptides. 相似文献
996.
997.
Muhammad Shahid Minhyung Kim Min Young Lee Austin Yeon Sungyong You Hyung L. Kim Jayoung Kim 《Proteomics》2019,19(11)
Metabolic alterations in prostate cancer (PC) are associated with progression and aggressiveness. However, the underlying mechanisms behind PC metabolic functions are unknown. The authors’ group recently reported on the important role of centromere protein F (CENPF), a protein associated with the centromere–kinetochore complex and chromosomal segregation during mitosis, in PC MRI visibility. This study focuses on discerning the role of CENPF in metabolic perturbation in human PC3 cells. A series of bioinformatics analyses shows that CENPF is one gene that is strongly associated with aggressive PC and that its expression is positively correlated with metastasis. By identifying and reconstructing the CENPF network, additional associations with lipid regulation are found. Further untargeted metabolomics analysis using gas chromatography‐time‐of‐flight‐mass spectrometry reveals that silencing of CENPF alters the global metabolic profiles of PC cells and inhibits cell proliferation, which suggests that CENPF may be a critical regulator of PC metabolism. These findings provide useful scientific insights that can be applied in future studies investigating potential targets for PC treatment. 相似文献
998.
Hunhee Lim Donghun Kim Min‐Jae Choi Edward H. Sargent Yeon Sik Jung Jin Young Kim 《Liver Transplantation》2019,9(48)
Quantum‐dot (QD) photovoltaics (PVs) offer promise as energy‐conversion devices; however, their open‐circuit‐voltage (VOC) deficit is excessively large. Previous work has identified factors related to the QD active layer that contribute to VOC loss, including sub‐bandgap trap states and polydispersity in QD films. This work focuses instead on layer interfaces, and reveals a critical source of VOC loss: electron leakage at the QD/hole‐transport layer (HTL) interface. Although large‐bandgap organic materials in HTL are potentially suited to minimizing leakage current, dipoles that form at an organic/metal interface impede control over optimal band alignments. To overcome the challenge, a bilayer HTL configuration, which consists of semiconducting alpha‐sexithiophene (α‐6T) and metallic poly(3,4‐ethylenedioxythiphene) polystyrene sulfonate (PEDOT:PSS), is introduced. The introduction of the PEDOT:PSS layer between α‐6T and Au electrode suppresses the formation of undesired interfacial dipoles and a Schottky barrier for holes, and the bilayer HTL provides a high electron barrier of 1.35 eV. Using bilayer HTLs enhances the VOC by 74 mV without compromising the JSC compared to conventional MoO3 control devices, leading to a best power conversion efficiency of 9.2% (>40% improvement relative to relevant controls). Wider applicability of the bilayer strategy is demonstrated by a similar structure based on shallow lowest‐unoccupied‐molecular‐orbital (LUMO) levels. 相似文献
999.
1000.
Mutational and epigenetic driver events profoundly alter intercellular communication pathways in cancer. This effect includes deregulated release, molecular composition, and biological activity of extracellular vesicles (EVs), membranous cellular fragments ranging from a few microns to less than 100 nm in diameter and filled with bioactive molecular cargo (proteins, lipids, and nucleic acids). While EVs are usually classified on the basis of their physical properties and biogenetic mechanisms, recent analyses of their proteome suggest a larger than expected molecular diversity, a notion that is also supported by multicolour nano‐flow cytometry and other emerging technology platforms designed to analyze single EVs. Both protein composition and EV diversity are markedly altered by oncogenic transformation, epithelial to mesenchymal transition, and differentiation of cancer stem cells. Interestingly, only a subset of EVs released from mutant cells may carry oncogenic proteins (e.g., EGFRvIII), hence, these EVs are often referred to as “oncosomes”. Indeed, oncogenic transformation alters the repertoire of EV‐associated proteins, increases the presence of pro‐invasive cargo, and alters the composition of distinct EV populations. Molecular profiling of single EVs may reveal a more intricate effect of transforming events on the architecture of EV populations in cancer and shed new light on their biological role and diagnostic utility. 相似文献