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Black phosphorus (BP) has been recognized as an ideal anode material for fast‐charging lithium (Li)‐ion capacitors (LICs) due to its high theoretical capacity (2596 mAh g−1), appropriate lithiation potential (0.7 V vs Li+/Li) and fast ion diffusion capability. However, large volume change and soluble polyphosphides (LixPs)‐based intermediates during charging‐discharging process seriously deteriorate cycling performance. To address the aforementioned issues, an elaborated design is reported on the binder for BP electrode. The ‐NH2 polar functional group in grafted chitosan (GCS) binder presents strong chemical anchoring effect for both BP and soluble LixPs, achieving superior adhesion force and LixPs constraining capability for enhanced structure integrity of BP electrode. In addition, GCS exhibits strong Li‐ion binding energy that promotes the Li‐ion adsorption at electrode level, leading to a boosted cycle life for BP. As a result, the graphene (G) incorporated BP electrode using GCS binder shows specific capacity of 997.6 mAh g−1 after 400 cycles at 1 A g−1. This study unravels the crucial role of functional groups for binder in high‐performance BP electrode. [ABSTRACT FROM AUTHOR]

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The 2D layered hexagonal boron nitride (hBN) material is a promising platform for making single photon emitters (SPEs). Integrate SPEs with photonic cavities or waveguides, requires the deterministic positioning of these emitters as accurately as possible. Among all of the alternative techniques, He+ focused ion beam (FIB) theoretically has sub‐nanometer precision, but its practical positioning accuracy in processing SPEs is limited by the inevitable detrimental byproduct defects. So far, it remains challenging to achieve an accuracy below 100 nm for the positioning of SPEs in hBN. Here, we present a two‐step method for creating SPEs at the predetermined positions in hBN that combines the He+ FIB irradiation and thermal annealing under an oxygen atmosphere. With this method, we have realized the positioning accuracy of less than 50 nm, which, to the best of our knowledge, stands as the highest among the currently available hBN SPEs preparation methods. Moreover, the SPE conversion yield was over 35% and the emission brightness of individual SPE achieved up to 3 × 105 counts/s at room temperature. These SPEs fabricated precisely with nanoscale accuracy in hBN are expected to be good candidates for making large‐scale integrated SPEs in photonic circuits. [ABSTRACT FROM AUTHOR]

Background: Aberrant activation of Wnt/β-catenin signaling by dysregulated post-translational protein modifications, especially ubiquitination is causally linked to cancer development and progression. Although Lys48-linked ubiquitination is known to regulate Wnt/β-catenin signaling, it remains largely obscure how other types of ubiquitination, such as linear ubiquitination governs its signaling activity. Methods: The expression and regulatory mechanism of linear ubiquitin chain assembly complex (LUBAC) on Wnt/β-catenin signaling was examined by immunoprecipitation, western blot and immunohistochemical staining. The ubiquitination status of β-catenin was detected by ubiquitination assay. The impacts of SHARPIN, a core component of LUBAC on malignant behaviors of gastric cancer cells were determined by various functional assays in vitro and in vivo. Results: Unlike a canonical role in promoting linear ubiquitination, SHARPIN specifically interacts with β-catenin to maintain its protein stability. Mechanistically, SHARPIN competes with the E3 ubiquitin ligase β-Trcp1 for β-catenin binding, thereby decreasing β-catenin ubiquitination levels to abolish its proteasomal degradation. Importantly, SHARPIN is required for invasiveness and malignant growth of gastric cancer cells in vitro and in vivo, a function that is largely dependent on its binding partner β-catenin. In line with these findings, elevated expression of SHARPIN in gastric cancer tissues is associated with disease malignancy and correlates with β-catenin expression levels. Conclusions: Our findings reveal a novel molecular link connecting linear ubiquitination machinery and Wnt/β-catenin signaling via SHARPIN-mediated stabilization of β-catenin. Targeting the linear ubiquitination-independent function of SHARPIN could be exploited to inhibit the hyperactive β-catenin signaling in a subset of human gastric cancers. [ABSTRACT FROM AUTHOR]

Copyright of Oncologist is the property of Oxford University Press / USA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Author(s): Ke-Wei Liu [1, 2]; Zhong-Jian Liu [3]; LaiQiang Huang (corresponding author) [1]; Li-Qiang Li [3]; Li-Jun Chen [3]; Guang-Da Tang [3, 4] Mating in flowering plants normally relies on [...]

Orchidaceae, renowned for its spectacular flowers and other reproductive and ecological adaptations, is one of the most diverse plant families. Here we present the genome sequence of the tropical epiphytic orchid Phalaenopsis equestris, a frequently used parent species for orchid breeding. P. equestris is the first plant with crassulacean acid metabolism (CAM) for which the genome has been sequenced. Our assembled genome contains 29,431 predicted protein-coding genes. We find that contigs likely to be underassembled, owing to heterozygosity, are enriched for genes that might be involved in self-incompatibility pathways. We find evidence for an orchid-specific paleopolyploidy event that preceded the radiation of most orchid clades, and our results suggest that gene duplication might have contributed to the evolution of CAM photosynthesis in P. equestris. Finally, we find expanded and diversified families of MADS-box C/D-class, B-class AP3 and AGL6-class genes, which might contribute to the highly specialized morphology of orchid flowers. [ABSTRACT FROM AUTHOR]

We demonstrate a novel type of ZnO self-powered photodetector based on the asymmetric metal-semiconductor-metal (MSM) structure: one Au interdigitated electrode with wide fingers and the other one with narrow fingers. These ZnO photodetectors exhibit attractive photovoltaic characteristics at 0 V bias. More interestingly, with increasing the asymmetric ratio (the width of wide fingers : the width of narrow fingers) of the interdigitated electrodes, the responsivity of the ZnO self-powered UV photodetectors was enhanced obviously, reaching as high as 20 mA W−1 when the asymmetric ratio was 20 : 1. A physical model based on band energy theory was developed to illustrate the origin of the photoresponse at 0 V in our device. Our findings provide a new route to realizing self-powered photodetectors. [ABSTRACT FROM AUTHOR]

The coupling interaction among metal nanoparticles can cause asymmetric distribution of the surface charges, which can lead to the cleavage of surface plasmon resonance. Higher order resonance modes in plasmonic nanostructures exhibit sharp resonance and dramatic line shape shifts. These unique resonant behaviours existing in nanostructures can be used to improve the performance of wide band gap semiconductor devices, such as increasing the output power of lasers. According to the theoretical calculation and simulation, silver nanoparticles have been prepared experimentally, and the corresponding extinction spectra were also tested to verify the simulation results. It is found that the hybrid quadrupolar resonance can indeed occur in the short wavelength region. [ABSTRACT FROM AUTHOR]

Background: The Aerides–Vanda alliance is a complex group in the subtribe Aeridinae (subfamily Epidendroideae, Orchidaceae). Some phylogenetic systems of this alliance have been previously proposed based on molecular and morphological analyses. However, several taxonomic problems within this alliance as well as between it and its allies remain unsolved. Methodology/Principal Findings: We utilized ITS and five plastid DNA regions in this phylogenetic analysis. Consensus trees strongly indicate that the Aerides–Vanda alliance is monophyletic, and the 14 genera of this alliance can be grouped into the following clades with 14 subclades: 1. Aerides, comprising two subclades: Rhynchostylis and Aerides; 2. Ascocentropsis; 3. Papilionanthe; 4. Vanda, comprising five subclades: Neofinetia, Christensonia, Seidenfadenia, Ascocentrum, and Vanda–Trudelia, in which Vanda and Trudelia form a subclade; 5. Tsiorchis, comprising three subclades: Chenorchis, Tsiorchis, and two species of Ascocentrum; 6. Paraholcoglossum; and 7. Holcoglossum. Among the 14 genera, only Ascocentrum is triphyletic: two species of the Ascocentrum subclade, an independent subclade Ascocentrum subclade in the Tsiorchis clade; the Ascocentrum subclade in the Vanda clade; and one species in the Holcoglossum clade. The Vanda and Trudelia species belong to the same subclade. The molecular conclusion is consistent with their morphological characteristics. Conclusions: We elucidate the relationship among the 14 genera of the Aerides–Vanda alliance. Our phylogenetic results reveal that the Aerides–Vanda alliance is monophyletic, but it can be divided into 14 genera. The data prove that Ascocentrum is triphyletic. Plants with elongate-terete leaves and small flowers should be treated as a new genus, Pendulorchis. Saccolabium himalaicum (Ascocentrum himalaicum) should be transferred to Pendulorchis. Ascocentrum pumilum, endemic to Taiwan, should be transferred to Holcoglossum. A new combination, Holcoglossum pumilum, was also established. Trudelia should not be recognized as an independent genus. Two new species, Pendulorchis gaoligongensis and Holcoglossum singchianum, were described as well. [ABSTRACT FROM AUTHOR]

Background: Orchids have numerous species, and their speciation rates are presumed to be exceptionally high, suggesting that orchids are continuously and actively evolving. The wide diversity of orchids has attracted the interest of evolutionary biologists. In this study, a new orchid was discovered on Danxia Mountain in Guangdong, China. However, the phylogenetic clarification of this new orchid requires further molecular, morphological, and phytogeographic analyses. Methodology/Principal Findings: A new orchid possesses a labellum with a large Y-shaped callus and two sacs at the base, and cylindrical, fleshy seeds, which make it distinct from all known orchid genera. Phylogenetic methods were applied to a matrix of morphological and molecular characters based on the fragments of the nuclear internal transcribed spacer, chloroplast matK, and rbcL genes of Orchidaceae (74 genera) and Calypsoeae (13 genera). The strict consensus Bayesian inference phylogram strongly supports the division of the Calypsoeae alliance (not including Dactylostalix and Ephippianthus) into seven clades with 11 genera. The sequence data of each species and the morphological characters of each genus were combined into a single dataset. The inferred Bayesian phylogram supports the division of the 13 genera of Calypsoeae into four clades with 13 subclades (genera). Based on the results of our phylogenetic analyses, Calypsoeae, under which the new orchid is classified, represents an independent lineage in the Epidendroideae subfamily. Conclusions: Analyses of the combined datasets using Bayesian methods revealed strong evidence that Calypsoeae is a monophyletic tribe consisting of eight well-supported clades with 13 subclades (genera), which are all in agreement with the phytogeography of Calypsoeae. The Danxia orchid represents an independent lineage under the tribe Calypsoeae of the subfamily Epidendroideae. This lineage should be treated as a new genus, which we have named Danxiaorchis, that is parallel to Yoania. Both genera are placed under the subtribe Yoaniinae. [ABSTRACT FROM AUTHOR]

Background: In the past century, the global average temperature has increased by approximately 0.74°C and extreme weather events have become prevalent. Recent studies have shown that species have shifted from high-elevation areas to low ones because the rise in temperature has increased rainfall. These outcomes challenge the existing hypothesis about the responses of species to climate change. Methodology/Principal Findings: With the use of data on the biological characteristics and reproductive behavior of Cephalantheropsis obcordata in Luofu Mountain, Guangdong, China, trends in the population size of the species were predicted based on several factors. The response of C. obcordata to climate change was verified by integrating it with analytical findings on meteorological data and an artificially simulated environment of water change. The results showed that C. obcordata can grow only in waterlogged streams. The species can produce fruit with many seeds by insect pollination; however, very few seeds can burgeon to become seedlings, with most of those seedlings not maturing into the sexually reproductive phase, and grass plants will die after reproduction. The current population's age pyramid is kettleshaped; it has a Deevey type I survival curve; and its net reproductive rate, intrinsic rate of increase, as well as finite rate of increase are all very low. The population used in the artificial simulation perished due to seasonal drought. Conclusions: The change in rainfall patterns caused by climate warming has altered the water environment of C. obcordata in Luofu Mountain, thereby restricting seed burgeoning as well as seedling growth and shortening the life span of the plant. The growth rate of the C. obcordata population is in descending order, and models of population trend predict that the population in Luofu Mountain will disappear in 23 years. [ABSTRACT FROM AUTHOR]

A correction to the article “The genome sequence of the orchid Phalaenopsis equestris" that was published online on November 24, 2014 is presented.

Abstract: Mg x Zn1−x O alloy films were prepared on sapphire substrates using Ar and N2 as the sputtering gases. The effect of the sputtering gas on the structural, optical and electrical properties of the Mg x Zn1−x O films was studied. By using N2 as the sputtering gas, the Mg x Zn1−x O film shows p-type conductivity and the band gap is larger than that employing Ar as the sputtering gas. The reason for this phenomenon is thought to be related to the reaction between N–O or N–Zn, and the N-doping. [Copyright &y& Elsevier]

Human tumorigenesis resembles embryogenesis by aberrant activation of several developmental pathways including Wnt/β-catenin signaling. Norrin is an atypical ligand for Frizzled receptor that is preferentially expressed in the endothelium to promote retinal vascularization during development. However, its expression pattern and potential roles in human cancers remain unclear. Here we report that Norrin expression is elevated in the parenchymal cells, but not endothelial cells, in gastric cancer (GC). Moreover, Norrin is required for growth and invasion of GC cells and its expression status is associated with unfavorable outcomes. However, analysis of the TGCA database demonstrates that Norrin expression status is not correlated with key target genes of Wnt/β-catenin signaling. Among several signaling pathways hyperactivated in cancer, Norrin -depleted GC cells also display down-regulated AKT signaling except the canonical Wnt/β-catenin signaling. Consistently, small molecule-induced cytosolic activation of AKT partially rescues the proliferative and invasive capability of Norrin -depleted cells. Together, these findings suggest a novel role of Norrin in gastric tumorigenesis that could be exploited for adjuvant therapy against the deadly malignancy. • Norrin is elevated in gastric cancer cells, but not endothelial cells. • In addition to Wnt/β-catenin signaling, Norrin activates AKT signaling in GC cells. • Activation of AKT signaling is required for Norrin to promote malignancy of GC. [ABSTRACT FROM AUTHOR]

Cancer metastasis, a leading cause of death in patients, is associated with aberrant expression of epigenetic modifiers, yet it remains poorly defined how epigenetic readers drive metastatic growth and whether epigenetic readers are targetable to control metastasis. Here, we report that bromodomain-containing protein 4 (BRD4), a histone acetylation reader and emerging anticancer therapeutic target, promotes progression and metastasis of gastric cancer. The abundance of BRD4 in human gastric cancer tissues correlated with shortened metastasis-free gastric cancer patient survival. Consistently, BRD4 maintained invasiveness of cancer cells in vitro and their dissemination at distal organs in vivo . Surprisingly, BRD4 function in this context was independent of its putative transcriptional targets such as MYC or BCL2, but rather through stabilization of Snail at posttranslational levels. In an acetylation-dependent manner, BRD4 recognized acetylated lysine 146 (K146) and K187 on Snail to prevent Snail recognition by its E3 ubiquitin ligases FBXL14 and β-Trcp1, thereby inhibiting Snail polyubiquitination and proteasomal degradation. Accordingly, genome-wide transcriptome analyses identified that BRD4 and Snail regulate a partially shared metastatic gene signature in gastric cancer cells. These findings reveal a noncanonical posttranscriptional regulatory function of BRD4 in maintaining cancer growth and dissemination, with immediate translational implications for treating gastric metastatic malignancies with clinically available bromodomain inhibitors. SIGNIFICANCE: These findings reveal a novel posttranscriptional regulatory function of the epigenetic reader BRD4 in cancer metastasis via stabilizing Snail, with immediate translational implication for treating metastatic malignancies with clinically available bromodomain inhibitors. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/79/19/4869/F1.large.jpg., (©2019 American Association for Cancer Research.)

Mixed-phase ZnMgO (m-ZMO) thin films with a single absorption edge tuning from ∼3.9 to ∼4.8 eV were realized on a-face sapphire (a-Al2O3) by plasma-assisted molecular beam epitaxy. The small lattice mismatch of both ZnO and MgO with a-Al2O3 should be responsible for the single and controllable absorption edge. Metal-semiconductor-metal (MSM) photodetectors were fabricated based on these m-ZMO films, and the devices have the single cutoff wavelength, which can be tuned from 335 to 275 nm. These devices possess low dark current (78 pA for m-Z0.67M0.33O, 11 pA for m-Z0.59M0.41O, and 4 pA for m-Z0.39M0.61O at 40 V) and high responsivity (434 A/W for m-Z0.67M0.33O, 89.8 A/W for m-Z0.59M0.41O, and 3.7 A/W for m-Z0.39M0.61O at 40 V). Further response study reveals that the 90-10% decay time of m-Z0.67M0.33O, m-Z0.59M0.41O, and m-Z0.39M0.61O is around 37, 30, and 0.7 ms, respectively. Large amounts of heterojunction interfaces between wurtzite ZMO and cubic rock-salt ZMO could be responsible for the low dark current and high responsivity of our mixed-phase devices. The excellent comprehensive performance of m-ZMO UV photodetectors on a-Al2O3 suggests that m-ZMO UV photodetectors should have great applied potential.

MgZnO heterostructure light-emitting devices (LEDs) have been fabricated from p-Mg(0.35)Zn(0.65)O/n-Mg(0.20)Zn(0.80)O structures, and the p-type Mg(0.35)Zn(0.65)O film was realized using a lithium-nitrogen codoping method. Obvious ultraviolet emission peaked at around 355 nm dominates the electroluminescence (EL) spectra of the device at room temperature, which comes from the near-band-edge emission of the n-type Mg(0.20)Zn(0.80)O film. This is the first report on MgZnO heterostructured LEDs and the shortest EL emission ever reported in ZnO-based p-n junction LEDs to the best of our knowledge.

Background: Orchids have numerous species, and their speciation rates are presumed to be exceptionally high, suggesting that orchids are continuously and actively evolving. The wide diversity of orchids has attracted the interest of evolutionary biologists. In this study, a new orchid was discovered on Danxia Mountain in Guangdong, China. However, the phylogenetic clarification of this new orchid requires further molecular, morphological, and phytogeographic analyses., Methodology/principal Findings: A new orchid possesses a labellum with a large Y-shaped callus and two sacs at the base, and cylindrical, fleshy seeds, which make it distinct from all known orchid genera. Phylogenetic methods were applied to a matrix of morphological and molecular characters based on the fragments of the nuclear internal transcribed spacer, chloroplast matK, and rbcL genes of Orchidaceae (74 genera) and Calypsoeae (13 genera). The strict consensus Bayesian inference phylogram strongly supports the division of the Calypsoeae alliance (not including Dactylostalix and Ephippianthus) into seven clades with 11 genera. The sequence data of each species and the morphological characters of each genus were combined into a single dataset. The inferred Bayesian phylogram supports the division of the 13 genera of Calypsoeae into four clades with 13 subclades (genera). Based on the results of our phylogenetic analyses, Calypsoeae, under which the new orchid is classified, represents an independent lineage in the Epidendroideae subfamily., Conclusions: Analyses of the combined datasets using Bayesian methods revealed strong evidence that Calypsoeae is a monophyletic tribe consisting of eight well-supported clades with 13 subclades (genera), which are all in agreement with the phytogeography of Calypsoeae. The Danxia orchid represents an independent lineage under the tribe Calypsoeae of the subfamily Epidendroideae. This lineage should be treated as a new genus, which we have named Danxiaorchis, that is parallel to Yoania. Both genera are placed under the subtribe Yoaniinae.

Background: Outcrossing is known to carry genetic advantages in comparison with inbreeding. In many cases, flowering plants develop a self-incompatibility mechanism, along with a floral component adaptation mechanism, to avoid self-pollination and to promote outbreeding. Orchids commonly have a lip in their flower that functions as the a visiting plate for insect pollinators. Aside from the lip, however, many species (including Coelogyne rigida) have sheaths around the axis of inflorescence. The function of these sheaths remains unknown, and has long been a puzzle to researchers., Methodology/principal Findings: We investigated the function of these sheaths in relation to the lip and the pollinators, as well as their role in the modes of pollination and reproduction of Coelogyne rigida in 30 flowering populations of orchids in the limestone area of Southeast Yunnan, China. We found that self-incompatible C. rigida developed specialized bird perches around the basal axis of inflorescence to attract sunbirds and to complement their behavioral tendency to change foraging locations frequently. This self-incompatibility mechanism operates separately from the floral component adaptation mechanism. This mechanism thus prevents bees from repeatedly visiting the floral lip of the same plant which, in turn, results in autogamy. In this way, instead of preventing autogamy, C. rigida responds to these negative effects through a highly efficient cross-pollination method that successfully transfers pollen to different plants., Conclusions: The proposed method ensures reproductive success, while offsetting the infertile self-pollination by insects, thereby reducing mating costs and addressing the lack of cross-pollination. The adaptation provides a novel and striking example of structural adaptation that promotes cross-pollination in angiosperms.