WS2 ribbon arrays with defined chirality and coherent polarity.

One-dimensional transition metal dichalcogenides exhibiting an enhanced bulk photovoltaic effect have the potential to exceed the Shockley-Queisser limit efficiency in solar energy harvest within p-n junction architectures. However, the collective output of these prototype devices remains a challenge. We report on the synthesis of single-crystalline WS2 ribbon arrays with defined chirality and coherent polarity through an atomic manufacturing strategy. The chirality of WS2 ribbon was defined by substrate couplings into tunable armchair, zigzag, and chiral species, and the polarity direction was determined by the ribbon-precursor interfacial energy along a coherent direction. A single armchair ribbon showed strong bulk photovoltaic effect and the further integration of ~1000 aligned ribbons with coherent polarity enabled upscaling of the photocurrent.

Modularized batch production of 12-inch transition metal dichalcogenides by local element supply.

Two-dimensional (2D) transition metal dichalcogenides (TMDs) are regarded as pivotal semiconductor candidates for next-generation devices due to their atomic-scale thickness, high carrier mobility and ultrafast charge transfer. In analog to the traditional semiconductor industry, batch production of wafer-scale TMDs is the prerequisite to proceeding with their integrated circuits evolution. However, the production capacity of TMD wafers is typically constrained to a single and small piece per batch (mainly ranging from 2 to 4 inches), due to the stringent conditions required for effective mass transport of multiple precursors during growth. Here we developed a modularized growth strategy for batch production of wafer-scale TMDs, enabling the fabrication of 2-inch wafers (15 pieces per batch) up to a record-large size 12-inch wafers (3 pieces per batch). Each module, comprising a self-sufficient local precursor supply unit for robust individual TMD wafer growth, is vertically stacked with others to form an integrated array and thus a batch growth. Comprehensive characterization techniques, including optical spectroscopy, electron microscopy, and transport measurements unambiguously illustrate the high-crystallinity and the large-area uniformity of as-prepared monolayer films. Furthermore, these modularized units demonstrate versatility by enabling the conversion of as-produced wafer-scale MoS2 into various structures, such as Janus structures of MoSSe, alloy compounds of MoS2(1-x)Se2x, and in-plane heterostructures of MoS2-MoSe2. This methodology showcases high-quality and high-yield wafer output and potentially enables the seamless transition from lab-scale to industrial-scale 2D semiconductor complementary to silicon technology.

JHDM1D-AS1-driven inhibition of miR-940 releases ARTN expression to induce breast carcinogenesis

Introduction As ceRNA network of long non-coding RNA (lncRNA)–microRNA (miR)–messenger RNAs (mRNA) can be predicted on the basis of bioinformatics tools, we are now one step closer to deeper understanding carcinogenic mechanisms. In this study, we clarified the mechanistic understanding of JHDM1D-AS1-miR-940-ARTN ceRNA network in the development of breast cancer (BC). Materials and Methods The lncRNA–miRNA–mRNA interaction of interest was predicted by in silico analysis and identified by conducting RNA immunoprecipitation, RNA pull-down and luciferase assays. The expression patterns of JHDM1D-AS1, miR-940 and ARTN in BC cells were altered by lentivirus infection and plasmid transfection for functional assays on the biological properties of BC cells. Finally, the tumorigenic and metastatic abilities of BC cells were assessed in vivo. Results JHDM1D-AS1 was highly expressed, while miR-940 was poorly expressed in BC tissues and cells. JHDM1D-AS1 could competitively bind to miR-940, whereby promoting the malignant behaviors of BC cells. Furthermore, ARTN was identified as a target gene of miR-940. Through targeting ARTN, miR-940 exerted a tumor-suppressive role. In vivo experiments further confirmed that JHDM1D-AS1 enhanced the tumorigenesis and metastasis through up-regulation of ARTN. Conclusions Taken together, our study demonstrated the involvement of ceRNA network JHDM1D-AS1-miR-940-ARTN in the progression of BC, which highlighted promising therapeutic targets for BC treatment (AU)

Effect of ultrasonic-induced selenium crystallization behavior during selenium reduction.

In this work, the crystallization process of selenium was accelerated by ultrasonic wave. The effects of ultrasonic waves and conventional conditions of selenium crystallization were compared to understand the effects of different conditions on crystallization, including ultrasonic time, ultrasonic power, reduction temperature, and H2SeO3 concentration. The mechanism of ultrasound affecting selenium crystallization was also investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The experimental results showed that ultrasonic time, ultrasonic power, and reduction temperature significantly influenced the crystallization process and morphology of selenium. Ultrasonic time had a large effect on the completeness (all products have been crystallized) and integrity of the crystallization of the products. Meanwhile, ultrasonic power and reduction temperature had no effect on the completeness of crystallization. However, it had a significant effect on the morphology and integrity of the crystallized products, and different morphologies of the nano-selenium materials could be obtained by changing the ultrasonic parameters. Both primary and secondary nucleation are important in the process of ultrasound-accelerated selenium crystallization. The cavitation effect and mechanical fluctuant effects generated by ultrasound could reduce the crystallization induction time and accelerate the primary nucleation rate. The high-speed micro-jet formed in the rupture of the cavitation bubble generated is the most important reason to influence the secondary nucleation of the system.

JHDM1D-AS1-driven inhibition of miR-940 releases ARTN expression to induce breast carcinogenesis.

INTRODUCTION: As ceRNA network of long non-coding RNA (lncRNA)-microRNA (miR)-messenger RNAs (mRNA) can be predicted on the basis of bioinformatics tools, we are now one step closer to deeper understanding carcinogenic mechanisms. In this study, we clarified the mechanistic understanding of JHDM1D-AS1-miR-940-ARTN ceRNA network in the development of breast cancer (BC). MATERIALS AND METHODS: The lncRNA-miRNA-mRNA interaction of interest was predicted by in silico analysis and identified by conducting RNA immunoprecipitation, RNA pull-down and luciferase assays. The expression patterns of JHDM1D-AS1, miR-940 and ARTN in BC cells were altered by lentivirus infection and plasmid transfection for functional assays on the biological properties of BC cells. Finally, the tumorigenic and metastatic abilities of BC cells were assessed in vivo. RESULTS: JHDM1D-AS1 was highly expressed, while miR-940 was poorly expressed in BC tissues and cells. JHDM1D-AS1 could competitively bind to miR-940, whereby promoting the malignant behaviors of BC cells. Furthermore, ARTN was identified as a target gene of miR-940. Through targeting ARTN, miR-940 exerted a tumor-suppressive role. In vivo experiments further confirmed that JHDM1D-AS1 enhanced the tumorigenesis and metastasis through up-regulation of ARTN. CONCLUSIONS: Taken together, our study demonstrated the involvement of ceRNA network JHDM1D-AS1-miR-940-ARTN in the progression of BC, which highlighted promising therapeutic targets for BC treatment.

Engineering Interlayer Electron-Phonon Coupling in WS2/BN Heterostructures.

In van der Waals (vdW) heterostructures, the interlayer electron-phonon coupling (EPC) provides one unique channel to nonlocally engineer these elementary particles. However, limited by the stringent occurrence conditions, the efficient engineering of interlayer EPC remains elusive. Here we report a multitier engineering of interlayer EPC in WS2/boron nitride (BN) heterostructures, including isotope enrichments of BN substrates, temperature, and high-pressure tuning. The hyperfine isotope dependence of Raman intensities was unambiguously revealed. In combination with theoretical calculations, we anticipate that WS2/BN supercells could induce Brillouin-zone-folded phonons that contribute to the interlayer coupling, leading to a complex nature of broad Raman peaks. We further demonstrate the significance of a previously unexplored parameter, the interlayer spacing. By varying the temperature and high pressure, we effectively manipulated the strengths of EPC with on/off capabilities, indicating critical thresholds of the layer-layer spacing for activating and strengthening interlayer EPC. Our findings provide new opportunities to engineer vdW heterostructures with controlled interlayer coupling.

Robust growth of two-dimensional metal dichalcogenides and their alloys by active chalcogen monomer supply.

The precise precursor supply is a precondition for controllable growth of two-dimensional (2D) transition metal dichalcogenides (TMDs). Although great efforts have been devoted to modulating the transition metal supply, few effective methods of chalcogen feeding control were developed. Here we report a strategy of using active chalcogen monomer supply to grow high-quality TMDs in a robust and controllable manner, e.g., MoS2 monolayers perform representative photoluminescent circular helicity of ~92% and electronic mobility of ~42 cm2V-1s-1. Meanwhile, a uniform quaternary TMD alloy with three different anions, i.e., MoS2(1-x-y)Se2xTe2y, was accomplished. Our mechanism study revealed that the active chalcogen monomers can bind and diffuse freely on a TMD surface, which enables the effective nucleation, reaction, vacancy healing and alloy formation during the growth. Our work offers a degree of freedom for the controllable synthesis of 2D compounds and their alloys, benefiting the development of high-end devices with desired 2D materials.

Dual-coupling-guided epitaxial growth of wafer-scale single-crystal WS2 monolayer on vicinal a-plane sapphire.

The growth of wafer-scale single-crystal two-dimensional transition metal dichalcogenides (TMDs) on insulating substrates is critically important for a variety of high-end applications1-4. Although the epitaxial growth of wafer-scale graphene and hexagonal boron nitride on metal surfaces has been reported5-8, these techniques are not applicable for growing TMDs on insulating substrates because of substantial differences in growth kinetics. Thus, despite great efforts9-20, the direct growth of wafer-scale single-crystal TMDs on insulating substrates is yet to be realized. Here we report the successful epitaxial growth of two-inch single-crystal WS2 monolayer films on vicinal a-plane sapphire surfaces. In-depth characterizations and theoretical calculations reveal that the epitaxy is driven by a dual-coupling-guided mechanism, where the sapphire plane-WS2 interaction leads to two preferred antiparallel orientations of the WS2 crystal, and sapphire step edge-WS2 interaction breaks the symmetry of the antiparallel orientations. These two interactions result in the unidirectional alignment of nearly all the WS2 islands. The unidirectional alignment and seamless stitching of WS2 islands are illustrated via multiscale characterization techniques; the high quality of WS2 monolayers is further evidenced by a photoluminescent circular helicity of ~55%, comparable to that of exfoliated WS2 flakes. Our findings offer the opportunity to boost the production of wafer-scale single crystals of a broad range of two-dimensional materials on insulators, paving the way to applications in integrated devices.

The HIF-1/SNHG1/miR-199a-3p/TFAM axis explains tumor angiogenesis and metastasis under hypoxic conditions in breast cancer.

Activation of hypoxia-inducible factors (HIFs) as a result of intratumoral hypoxia modulates a cascade of molecular pathways thus leading to angiogenesis and metastasis in many solid tumors, including breast cancer (BC). In our paper, we report a regulatory axis of HIF-1, SNHG1, miR-199a-3p, and mitochondrial transcription factor A (TFAM) involved in tumor angiogenesis and metastasis under hypoxic conditions in BC. The expression of SNHG1 was determined in human BC cells cultured in hypoxia (1% O2 , 24 h) and normoxia (20% O2 , 24 h). Cultured MDA-MB-231 cells were assayed for the proliferation, migration, invasion, angiogenesis in vitro by using EdU staining, transwell chamber assays, Matrigel-based angiogenesis assays, tumorigenesis, and lung metastasis in vivo by using an orthotopic-transplant model of human BC. Dual-luciferase reporter assay, chromatin immunoprecipitation quantitative polymerase chain reaction assay, fluorescence in situ hybridization assay, RNA-binding protein immunoprecipitation assay, and RNA pull-down were performed to test interaction between HIF-1 and SNHG1, SNHG1 and miR-199a-3p, miR-199a-3p and TFAM. SNHG1 was increased under hypoxic conditions at a HIF-1-dependent manner. SNHG1 knockdown tempered MDA-MB-231 cell proliferation, migration, invasion, angiogenesis, in vitro, tumorigenesis, and lung metastasis in vitro. SNHG1 was co-expressed with miR-199a-3p and regulated the TFAM, a target gene of miR-199a-3p. SNHG1 increased the TFAM by binding with miR-199a-3p, thus promoting BC development and metastasis. These results support a regulatory axis consisting of HIF-1, SNHG1, miR-199a-3p, and TFAM during BC development and metastasis under hypoxic conditions, providing an opportunity to develop targeted therapeutics for BC.

Ultrafast Optical Modulation of Harmonic Generation in Two-Dimensional Materials.

The modulation of optical harmonic generation in two-dimensional (2D) materials is of paramount importance in nanophotonic and nano-optoelectronic devices for their applications in optical switching and communication. However, an effective route with ultrafast modulation speed, ultrahigh modulation depth, and broad operation wavelength range is awaiting a full exploration. Here, we report that an optical pump can dynamically modulate the third harmonic generation (THG) of a graphene monolayer with a relative modulation depth above 90% at a time scale of 2.5 ps for a broad frequency ranging from near-infrared to ultraviolet. Our observation, together with the real-time, time-dependent density functional theory (TDDFT) simulations, reveals that this modulation process stems from nonlinear dynamics of the photoexcited carriers in graphene. The superior performance of the nonlinear all-optical modulator based on 2D materials paves the way for its potential applications including nanolasers and optical communication circuits.

Optical fibres with embedded two-dimensional materials for ultrahigh nonlinearity.

Nonlinear optical fibres have been employed for a vast number of applications, including optical frequency conversion, ultrafast laser and optical communication1-4. In current manufacturing technologies, nonlinearity is realized by the injection of nonlinear materials into fibres5-7 or the fabrication of microstructured fibres8-10. Both strategies, however, suffer from either low optical nonlinearity or poor design flexibility. Here, we report the direct growth of MoS2, a highly nonlinear two-dimensional material11, onto the internal walls of a SiO2 optical fibre. This growth is realized via a two-step chemical vapour deposition method, where a solid precursor is pre-deposited to guarantee a homogeneous feedstock before achieving uniform two-dimensional material growth along the entire fibre walls. By using the as-fabricated 25-cm-long fibre, both second- and third-harmonic generation could be enhanced by ~300 times compared with monolayer MoS2/silica. Propagation losses remain at ~0.1 dB cm-1 for a wide frequency range. In addition, we demonstrate an all-fibre mode-locked laser (~6 mW output, ~500 fs pulse width and ~41 MHz repetition rate) by integrating the two-dimensional-material-embedded optical fibre as a saturable absorber. Initial tests show that our fabrication strategy is amenable to other transition metal dichalcogenides, making these embedded fibres versatile for several all-fibre nonlinear optics and optoelectronics applications.

LINC00096 Promotes the Proliferation and Invasion by Sponging miR-383-5p and Regulating RBM3 Expression in Triple-Negative Breast Cancer.

BACKGROUND: Recent studies revealed that long non-coding RNAs (lncRNA) play crucial roles in cancer initiation and progression. However, the function and underlying mechanism of lncRNAs in triple-negative breast cancer (TNBC) are little investigated. METHODS: qRT-PCR was used to investigate LINC00096 expression in TNBC tissues and cells. Function assays were used to test the effects of LINC00096 on TNBC cells progression. In addition, luciferase reporter and qRT-PCR assays were used to determine the underlying mechanism of LINC00096 on TNBC progression. RESULTS: In our present study, we identify LINC00096 as one of the most upregulated lncRNA in TNBC progression by using microarray screening. High LINC00096 expression was obviously related to advanced tumor stage, metastasis, poor prognosis of patients. Loss-of-function assays showed that LINC00096 suppression reduced TNBC cells proliferation and invasive abilities in vitro. Mechanistically, we demonstrated that LINC00096 directly interacted with miR-383-5p, subsequently acted as a miRNA sponge to increase RBM3 expression. CONCLUSION: In the present study, we indicated that LINC00096 might promote the proliferation and invasion through regulating the miR-383-5p/RBM3 pathway in TNBC, which providing a novel therapeutic target for cancer treatment.

Strong-coupled hybrid structure of carbon nanotube and MoS2 monolayer with ultrafast interfacial charge transfer.

Hybrid structures assembled by van der Waals (vdW) interactions greatly expand the conventional material platforms, as there is no constraint of lattice matching in the materials design. However, a general challenge lies in the controllable assembly of 1D-2D hybrids with strong-coupled interfaces, because the interaction area is very small and is easily disturbed by exotic molecules. Here, we report the direct construction of 1D carbon nanotube-2D MoS2 monolayer hybrids with strong interfacial coupling using a sequential chemical vapour deposition growth method. The strong mechanical and electronic couplings between the nanotubes and MoS2 are unambiguously illustrated from the Raman-mode frequency shift and ultrafast interfacial charge transfer (∼100 fs). The findings in this work will boost the mass fabrication of 1D-2D vdW hybrid materials with controllable interfacial geometry and coupling strength, and pave the way for their future applications in electronics, optoelectronics and photovoltaics.

Scaphoid instability caused by a giant cell tumour of the tendon sheath: A case report.

Giant-cell tumour of the tendon sheath (GCTTS) is a soft tissue tumour that may invade bone, causing an intrinsic osseous lesion or instability on radiographs. A case with scaphoid instability caused by a histologically-confirmed neighbouring GCTTS has rarely been described in the literature. No definite and radical method is available for the treatment of GCTTS. This report describes an unusual case of a 22-year-old woman who previously experienced a GCTTS in her right elbow, which was removed 10 years earlier. Currently, she presented with an enlarged painless right wrist mass with focal swelling. The mass has been present for 5 years. During the previous 6 months, she felt something pop and experienced pain with limited motion in her right wrist. Magnetic resonance imaging demonstrated a well-circumscribed soft tissue mass. Under general anaesthesia, complete surgical resection of the mass was undertaken. Histopathological examination revealed that the mass was a GCTTS. Less invasive leverage reduction with external fixator support and iliac crest bone autologous graft for treatment of carpal instability were performed. Radical resection combined with external fixator support and bone grafting can provide a new option for the treatment of carpal instability.

Long non-coding RNA MALAT1 promotes proliferation and invasion via targeting miR-129-5p in triple-negative breast cancer.

BACKGROUND: Long non-coding RNA Metastasis associated lung adenocarcinoma transcript 1(lncRNA MALAT1) play important roles in tumor progression. In the present study, we determined the regulatory function of MALAT1 in triple-negative breast cancer (TNBC). METHODS: A total of 43 cases of TNBC tissues and paired adjacent non-tumor tissues were collected for the research. MALAT1 expression was explored by qRT-PCR. In vitro functional validation experiments were used to determine the effect of MALAT1 on TNBC progression. We further identified the downstream target miRNAs for MALAT1. RESULTS: Relative expression of MALAT1 was increased in TNBC tissues and cell lines. High MALAT1 expression was closely correlated to advance clinical features and poor overall survival in TNBC patients. Function assay showed that MALAT1 silencing significantly decreased cell proliferation, migration, and invasion. Flow cytometry assay revealed that MALAT1 inhibition significantly induced cell cycle arrest in the G0/G1 phase. In addition, we showed that the roles of MALAT1 on TNBC cells progression was mediated by miR-129-5p. CONCLUSION: Our results demonstrated that the "MALAT1-miR-129-5p" axis might play an important role in the progression of TNBC, thereby might provide a potential therapeutic strategy for the treatment of TNBC.

Preparation and characterization of monodispersed microfloccules of TiO2 nanoparticles with immobilized multienzymes.

Microfloccules of TiO(2) nanoparticles, on which glycerol-dehydrogenase (GDH), 1,3-propanediol-oxidoreductase (PDOR), and glycerol-dehydratase (GDHt) were coimmobilized, were prepared by adsorption-flocculation with polyacrylamide (PAM). The catalytic activity of immobilized enzyme in the glycerol redox reaction system, the enzyme leakage, stabilities of pH and temperature, as well as catalytic kinetics of immobilized enzymes relative to the free enzymes were evaluated. Enzyme loading on the microfloccules as much as 104.1 mg/g TiO(2) (>90% loading efficiency) was obtained under the optimal conditions. PAM played a key role for the formation of microfloccules with relatively homogeneous distribution of size and reducing the enzyme leakage from the microfloccules during the catalysis reaction. The stabilities of GDH against pH and temperature was significantly higher than that those of free GDH. Kinetic study demonstrated that simultaneous NAD(H) regeneration was feasible in glycerol redox system catalysted by these multienzyme microfloccules and the yield of 1, 3-popanediol (1, 3-PD) was up to 11.62 g/L. These results indicated that the porous and easy-separation microfloccules of TiO(2) nanoparticles with immobilized multienzymes were efficient in term of catalytic activity as much as the free enzymes. Moreover, compared with free enzyme, the immobilized multienzymes system exhibited the broader pH, higher temperature stability.