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Colorectal cancer has become a disease with one of the highest incidence rates worldwide, and liver metastasis threatens the prognosis of colorectal cancer. MicroRNA (miR)‑200 and miR‑141 have been confirmed to be aberrantly expressed in colorectal cancer, however, whether miR‑200 and miR‑141 are involved in the progression of colorectal cancer, and their role in liver metastasis remain to be fully elucidated. The aim of the present study was to investigate the role of miR‑200 and miR‑141 in the progression and liver metastasis of colorectal cancer in patients. A total of 380 patients with colorectal cancer were enrolled, of which 142 were diagnosed with grade I/II disease and 238 were grade III/IV disease. Reverse transcription‑quantitative polymerase chain reaction analysis was performed to examine the serum levels of miR‑200 and miR‑141. In addition, transfection was performed in HCT116 and SW480 cells to establish overexpression models for miR‑200 and miR‑141. A TUNEL assay was performed to assess apoptosis and a Transwell experiment was performed to examine cell migration. Compared with the control group, the serum levels of miR‑200 and miR‑141 were significantly increased in the colorectal cancer group (P<0.05). Compared with the patients with colorectal cancer without liver metastasis, patients with liver metastasis had significantly higher serum levels of miR‑200 and miR‑141 (P<0.05). The overexpression of miR‑200 and miR‑141 inhibited apoptosis of the HC116 and SW480 cells, and enhanced cell migration. The upregulation of serum miR‑200 and miR‑141 were associated with liver metastasis in patients with colorectal cancer. Taken together, the overexpression of miR‑200 and miR‑141 exacerbated liver metastasis of colorectal cancer via inhibiting apoptosis and inducing migration. [ABSTRACT FROM AUTHOR]

A supramolecular compound, [Himi]6[As2Mo18O62]·11H2O (1) (imi = imidazole), has been synthesized and characterized by single crystal X-ray analysis, IR spectra, thermal gravimetric analysis, electrochemical and elemental analysis. The crystals are monoclinic, P 2(1)/n, a = 14.9529(8) Å, b = 20.9521(11) Å, c = 25.2464(13) Å, β = 93.8130(10)°, V = 7892.1(7) Å3, Z = 4. X-ray diffraction indicated that protonated imidazole cation and polyanion were linked together through electrostatic interactions and intermolecular forces (hydrogen bonding). (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Highly sensitive strain sensors show great potential for use in wearable health monitoring, autonomous intelligent robots and biomimetic prosthetics. The current resistive strain sensors mainly work through piezoresistors. Here, the robust tunneling mechanism based nanoscale strain sensors with high sensitivity are reported. The strain sensors are fabricated from graphene nanoparticle film. The sensitivity of graphene nanoparticle strain sensors could be tunable through the modulation of tunneling type, suggesting a theoretical support in performance optimization of tunneling strain sensors. The output characterization indicates the direct tunneling (DT) and Fowler–Nordheim tunneling (FNT) are dominant for charge carrier transport in the low voltage and high voltage regions, respectively. It is found that gauge factors are ∼79 at low voltage of 0–4 V, and ∼110 at high voltage of 20–40 V, showing profound dependence on DT and FNT types. The strain sensor bearing 0.3% strain shows a great stability over 100 cycles at bias voltage of 1 V and 40 V, respectively. An integrated strain sensor array with 5 × 5 patterned graphene nanoparticle film on a polyethylene terephthalate substrate is fabricated and demonstrates great spatial strain distribution, guiding the design for flexible and transparent strain sensor e-skins. [ABSTRACT FROM AUTHOR]

Two dimensional (2D) hexagonal boron nitride (h-BN) has attracted extensive attention due to its high thermal and chemical stability, excellent dielectric characteristic, and unique optical properties. However, the chemical vapor deposition synthesis of 2D h-BN is not fully explored, such as morphology regulation and size control. Here we demonstrate the growth of 2D h-BN single domains on Cu/Ni alloy via atmospheric chemical vapor deposition (APCVD). We discover that the shape of the as-grown h-BN single domains can be controlled from triangles, hexagons, to circles by adjusting the Ni content of the Cu/Ni substrates. Moreover, we find out that increasing the nickel content can suppress the nucleation density while the average domain size is accordingly improved. The grown single-crystalline h-BN demonstrates ultralow dark current about 0.9 pA and outstanding ultraviolet response with the responsivity up to 5.45 mAW−1. The response time are 376 and 198 ms. Our work sheds light on the controllable synthesis of 2D h-BN and promotes its applications in high ultraviolet detection. [ABSTRACT FROM AUTHOR]

Monolayer semiconductors of molybdenum disulfide (MoS2) crystals have drawn tremendous attention due to their extraordinary electronic and optical properties. A uniform and high-quality crystalline MoS2 monolayer is greatly needed in fundamental studies and practical applications. Three-point star to six-point star MoS2 nanosheets are readily synthesized in a controlled manner using the chemical vapor deposition method. A possible coalescent model is proposed to study the evolution of the six-point star MoS2 domain. A comparative study of field effect transistors are performed to disclose the negative effect of grain boundaries on the transport properties based on six-point star MoS2. [ABSTRACT FROM AUTHOR]