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More than 1 million women worldwide are diagnosed with breast cancer (BC) each year. This study aims to explore the molecular mechanisms of β-catenin affecting the trastuzumab tolerance in HER2-positive BC. β-catenin in BC and non-BC tissue samples were assessed by immunohistochemistry. β-catenin and HER2 were over-expressed and knockdown to evaluate their role in tumorigenicity and trastuzumab resistance in cell and animal models using soft-agar and xenograft assays. Confocal laser immunofluorescence assay and co-immunoprecipitation were used to assess protein-protein binding. Expression of genes was detected using Western blot analysis. β-catenin was highly expressed in primary and metastatic BC, overexpression of β-catenin increased the colony formation of MCF7 cells when it was co-expressed with HER2 and synergically increased the tumor size in immunodeficient mice. Overexpression of β-catenin also increased the phosphorylation of HER2 and HER3 and increased the size of tumor derived from HER2-elevated cells. Confocal laser immunofluorescence assay showed that β-catenin and HER2 were co-localized on the membrane of MDA-MB-231 cells, suggesting that β-catenin binds HER2 to activate the HER2 signaling pathway. Immunoprecipitation of β-catenin and HER2 also confirmed this binding. On the other hand, knockdown of β-catenin in MDA-MB-231 cell lines decreased the activity of SRC and decreased phosphorylation of HER2 at Y877 and Y1248. The interaction between HER2 and SRC was enhanced when β-catenin was overexpressed, and β-catenin increased the resistance of tumor derived from HER2 elevated BT474 cells to trastuzumab. Further analysis showed that trastuzumab inhibited the activation of HER3, but SRC was still highly expressed in cells overexpressing β-catenin. Our work demonstrates that β-catenin is highly expressed in BC and it synergically promotes formation and progress of BC with HER2. β-catenin binds with HER2 leading to enhanced interaction with SRC and resistance to trastuzumab.

Retroviruses exclusively infect vertebrates, causing a variety of diseases. The replication of retroviruses requires reverse transcription and integration into host genomes. When infecting germline cells, retroviruses become inherited vertically, forming endogenous retroviruses (ERVs). ERVs document past viral infections, providing molecular fossils for studying the evolutionary history of retroviruses. In this review, we summarize the recent advances in understanding the diversity and evolution of retroviruses from the perspectives of viral fossils, and discuss the effects of ERVs on the evolution of host biology.

Die postkoloniale Religionswissenschaft fragt nach der wissenschaftlichen Definition des Begriffs »Religion«, während im Alltag ein konsensbasiertes Verständnis von Religion existiert. Der vorliegende Beitrag untersucht welche Auswirkung diese Sichtweisen auf die Religionswissenschaft in China hat. Er geht der Frage nach, inwiefern ein Phänomen wissenschaftlich als »religiös« definiert bzw. anerkannt werden kann. Dazu werden im Folgenden die Theorien von drei zeitgenössischen chinesischen Religionsforschenden – Zhuo Xinping, Lv Daji und Mu Zhongjian – vorgestellt. Alle drei Religionswissenschaftler/innen betonen den kulturellen Charakter und die soziale Bedeutung von Religion, anstatt, wie bisher üblich, Religion als Instrument der Politik oder als psychologisches Gift zu interpretieren: Zur Etablierung einer objektiven und neutralen Position in der Religionswissenschaft verwendet Zhuo Xinping vor allem die Methode »Xuanzhi« (Beobachten vor Beurteilen). Lv Daji interpretiert Religion als eigenständiges System kultureller Symbole, indem er die Marxistische Religionstheorie wieder aufgreift. Mu Zhongjian versucht, die Besonderheit der Religion(en) in China herauszuarbeiten. Im Zuge der Bemühungen der chinesischen Religionsforschenden wird Religion, so die in diesem Beitrag vertretende These, in der chinesischen Gesellschaft zunehmend als kulturelles Phänomen betrachtet. Post-colonial studies of religions ask how the concept of religion can be scientifically defined when there is a consensus-based understanding of religion in everyday life. The subsequent investigation examines to which extent the Studies of Religion in contemporary China deal with this issue: namely, how a phenomenon can be scientifically defined or recognized as »religious«. For this purpose, the theories of three contemporary Chinese researchers in Studies of Religion – Zhuo Xinping, Lv Daji, and Mu Zhongjian – will be discussed in detail. The primary concern of these contemporary Chinese researchers is to emphasize the cultural character of religion in society instead of interpreting religion as an instrument of politics or as a psychological poison. To achieve this goal, Zhuo Xinping uses »Xuanzhi« (observing before judging) as the primary method to protect his objective and neutral position in the Studies of Religion. Lv Daji interprets »religion« as a unique system of cultural symbols in resuming the Marxist theory of religion. Mu Zhongjian tries to figure out the particularity of »Chinese religion« by clarifying the relationship between »Chinese religion« and Confucianism. This study claims, that as a result of their efforts, religion is increasingly treated as a normal cultural phenomenon in Chinese society.

To observe the effect of Yanggan Jiedu Sanjie (YGJDSJ) formula on human hepatocellular carcinoma Bel-7402 cells.Bel-7402 cells were treated with YGJDSJ. Cell proliferation was detected by cell counting kit-8 assay. Cell apoptosis was identified by Hoechst 33258 staining and flow cytometric analysis. Cell cycle distribution was quantified by flow cytometric analysis. Caspase activities were measured by commercial kit. Cell senescence was detected by senescence-associated β-galactosidase (SA-β-gal) staining. Protein expression and phosphorylation were identified by Western blot. Protein expression was knocked-down by siRNA.YGJDSJ inhibited proliferation of Bel- 7402 cells in a dose- and time-dependent manner. YGJDSJ induced apoptosis and activated caspase- 3, 8, and 9 in Bel-7402 cells. YGJDSJ-induced apoptosis was completely abrogated by a pan caspase inhibitor, Z-VAD-FMK. YGJDSJ also induced cell senescence, up-regulated cyclin-dependent kinase inhibitor 1a (CDKN1a) and CDKN2a expression and down-regulated retinoblastoma protein (RB) phosphorylation in Bel-7402 cells. Specific knockdown of CDKN1a and CDKN2a significantly reduced YGJDSJ-induce cell senescence in Bel-7402 cells.YGJDSJ inhibited cell proliferation, induced caspase-dependent apoptosis and CDKN1a/CDKN2a-RB signalling mediated cell senescence in Bel-7402 cells. Our findings suggest that YGJDSJ might be potential for hepatocellular carcinoma treatment.

In CH3NH3PbI3 perovskite solar cells, enhancement grain size of CH3NH3PbI3 to reduce the non-radiative at grain boundaries is an important way to reach high performance perovskite solar cell. However, it is still a challenge to enhance the grain size of CH3NH3PbI3 through a simple and low cost way. In this work, a larger precursor colloidal size is realized through tuning morphology of precursor CH3NH3I using a polar solvent of ethanol during purification, yielding a larger grain size of CH3NH3PbI3 film, and the as-prepared perovskite solar cells are shown to be dramatically increased to 17.49% with an increase in short circuit density, fill factor and open circuit voltage, as compared to that (14.28%) in the control device with CH3NH3I purified by non-polar solvent of diethyl ether. The investigation result showed the increased efficiency of perovskite solar cells prepared by ethanol purification is ascribed to a faster charge transfer at CH3NH3PbI3/TiO2 interface resulting from the reduced grain boundary defects. Our work provides a route for improving the CH3NH3PbI3 device efficiency through a simple yet effective approach.

Lateral transition-metal dichalcogenide and their heterostructures have attracted substantial attention, but there lacks a simple approach to produce large-scaled optoelectronic devices with graded composition. In particular, the incorporation of substitution and doping into heterostructure formation is rarely reported. Here, we demonstrate growth of a composition graded doped lateral WSe2/WS2 heterostructure by ambient pressure chemical vapor deposition in a single heat cycle. Through Raman and photoluminescence spectroscopy, we demonstrate that the monolayer heterostructure exhibits a clear interface between two domains and a graded composition distribution in each domain. The coexistence of two distinct doping modes, i.e., interstitial and substitutional doping, was verified experimentally. A distinct three-stage growth mechanism consisting of nucleation, epitaxial growth, and substitution was proposed. Electrical transport measurements reveal that this lateral heterostructure has representative charac...

Recently, single-walled carbon nanotube (SWNT) films have been regarded as a promising channel material for flexible photodetectors due to their high intrinsic carrier mobility, conductivity, and mechanical flexibility. However, the application of SWNTs in photonic devices is limited due to their weak light absorption and the absence of a gain mechanism. Here, we demonstrate a high-performance flexible photodetector that consists of a reticulated SWNT film covered with a thin film of CsPbI3 perovskite colloidal quantum dots. The unique hierarchical reticulated structure of the SWNTs provides such films with extremely high tensile strength and great extensibility, which can ensure the appropriate toughness for achieving flexible photodetectors. Meanwhile, the perovskite quantum dots enhance light absorption, thereby sensitizing the creation of free electrical carriers within the SWNTs. This hybrid photodetector exhibits an extended photonic response and gain compared with the original pure SWNT devices. In addition, the device exhibits good robustness against repetitive bending and stretching, suggesting its applicability as a large-area wearable flexible photodetector.

Ion migration in hybrid organic-inorganic perovskites has been suggested to be an important factor for many unusual behaviors in perovskite-based optoelectronics, such as current-voltage hysteresis, low-frequency giant dielectric response, and the switchable photovoltaic effect. However, the role played by ion migration in the photoelectric conversion process of perovskites is still unclear. In this work, we provide microscale insights into the influence of ion migration on the microstructure, stability, and light-matter interaction in perovskite micro/nanowires by using spatially resolved optical characterization techniques. We observed that ion migration, especially the migration of MA(+) ions, will induce a reversible structural swell-shrink in perovskites and recoverably affect the reflective index, quantum efficiency, light-harvesting, and photoelectric properties. The maximum ion migration quantity in perovskites was as high as approximately 30%, resulting in lattice swell or shrink of approximately 4.4%. Meanwhile, the evidence shows that ion migration in perovskites could gradually accelerate the aging of perovskites because of lattice distortion in the reversible structural swell-shrink process. Knowledge regarding reversible structural swell-shrink and recoverable optical properties may shed light on the development of optoelectronic and converse piezoelectric devices based on perovskites.

This thesis is mainly focused on the preparation of low-dimensional optical materials and fabrication of high performance optoelectronic devices including photodetectors, optical waveguides and optical modulators. There are three main sub-projects. In the first project, photodetectors based on lateral transition metal dichalcogenides (TMDs) heterostructure were fabricated and increased photoresponsivity and work area compared with previous work have been demonstrated. In the second project, highly flexible and durable photodetectors based on hybrid material consisting of carbon nanotube film and perovskite quantum dots were fabricated. In the third project, single-crystalline perovskite was restructured into active waveguides with low propagation loss and waveguide modulator with large light intensity modulation.

Lateral transition-metal dichalcogenide and their heterostructures have attracted substantial attention, but there lacks a simple approach to produce large-scaled optoelectronic devices with graded composition. In particular, the incorporation of substitution and doping into heterostructure formation is rarely reported. Here, we demonstrate growth of a composition graded doped lateral WSe

Organo-lead halide perovskites as a new class of exceptional optoelectronic materials has been found use in many applications. However, conventional methods for forming single crystals of OHPs afford limited control over the product morphology, rendering the assembly of defined microstructures difficult. We overcame this by synthesising for the first time (MA)[PbBr3]·DMF (1), and demonstrating its facile transformation into monocrystalline MAPbBr3 microplatelets, which exhibit excellent waveguiding porperty with an ultra-low propagation loss of 0.04 dB μm−1 and can be further tailored into a variety of waveguide based photonic devices. An efficient electro-optical modulator consisting of a MAPbBr3 non-linear arc waveguide was demonstrated, exhibiting a 98.4% PL intensity modulation with an external voltage of 45 V. This novel approach and the demonstration of effective waveguiding will pave the way for developing a wide range of photonic devices based on organo lead halide perovskites.

Metal-halide perovskites have been hailed as remarkable materials for photovoltaic devices and, recently, their star has also been on the rise in optoelectronics and photonics. In particular, the optical properties of a metal-halide perovskite can be widely manipulated once its bulk structure has been reduced to a low-dimensional structure, allowing multiple functionalities of light generation, emission, transmission, and detection to be realized in one material. In this paper, we highlight the recent advances in the synthesis of low-dimensional metal-halide perovskites and their unique properties as well as their novel optoelectronic and photonic applications. It is anticipated that this review can serve as an overview and evaluation of state-of-the-art synthesis techniques as well as nanoscale optoelectronics and photonics based on low-dimensional perovskite nanocrystals.

In article number 1600077, Bao et al. demonstrate large‐scale production of Bi2SexTe3‐x–graphene van deer Waals heterostructures using a solvothermal method. Free‐standing films produced from this heterostructure show improved electrical, photoelectric and mechanical properties, making their photoresponsive material promising for flexible photodetectors that can operate from visible to near‐infrared wavelengths.

Vertical heterojunctions of two two-dimensional (2D) transition metal dichalcogenides (TMDs) have attracted considerable attention recently. A variety of heterojunctions can be constructed by stacking different TMDs to form fundamental building blocks in different optoelectronic devices such as photodetectors, solar cells, and light-emitting diodes. However, these applications are significantly hampered by the challenges of large-scale production of van der Waals stacks of atomically thin materials. Here, we demonstrate scalable production of periodic patterns of few-layer WS2, MoS2, and their vertical heterojunction arrays by a thermal reduction sulfurization process. In this method, a two-step chemical vapor deposition approach was developed to effectively prevent the phase mixing of TMDs in an unpredicted manner, thus affording a well-defined interface between WS2 and MoS2 in the vertical dimension. As a result, large-scale, periodic arrays of few-layer WS2, MoS2, and their vertical heterojunctions can be produced with desired size and density. Photodetectors based on the as-produced MoS2/WS2 vertical heterojunction arrays were fabricated, and a high photoresponsivity of 2.3 A·W(-1) at an excitation wavelength of 450 nm was demonstrated. Flexible photodetector devices using MoS2/WS2 heterojunction arrays were also demonstrated with reasonable signal/noise ratio. The approach in this work is also applicable to other TMD materials and can open up the possibilities of producing a variety of vertical van der Waals heterojunctions in a large scale toward optoelectronic applications.

Large-scale production of 2D van der Waals heterostructures with precisely controlled chemical composition is the major challenge hindering their practical electric and optoelectronic applications. In this work, a solvothermal method is demonstrated to produce van der Waals heterostructures consisting of metal chalcogenides and graphene in a large scale. In situ powder X-ray diffraction reveals that graphene plays an important role as atomic template to grow bismuth chalcogenide nanoplatelets with preferential stoichiometry of Bi2Se1.5Te1.5, which is naturally unstable. It is found that Bi2Se1.5Te1.5 has the minimum lattice mismatch with graphene (