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An improved three-arm airbridge contacted microdisk diode structure is presented. Continuous-wave lasing from InGaAs quantum dot (QD) in a ~4-micron-diameter microdisks is reported with the threshold current ~40 uA at T = 5 K. With the increase of injection current, the QD's emission blueshifts due to the band-filling effect, while the laser mode peak redshifts by thermal effect. When the QD's gain spectra shift out of alignment with the lasing mode, the next available whispering gallery mode starts lasing from QD wetting layer. The thermal heating effect is discussed by investigating the modes redshift with respect to injection current.

OBJECTIVE: To detect the expression of long non-coding ribonucleic acid (lncRNA) NCK1-AS1 in non-small cell lung cancer (NSCLC), analyze the association between its expression and the clinicopathological characteristics of NSCLC patients, and study the biological function of NCK1-AS1 in vitro. PATIENTS AND METHODS: The relative expression of NCK1-AS1 in NSCLC tissues and cells was detected via quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The association between the expression of NCK1-AS1 and the clinicopathological characteristics of NSCLC was statistically analyzed. The effects of interference in the expression of NCK1-AS1 on the biological behaviors of NSCLC cells were detected via in vitro experiments, including Cell Counting Kit-8 (CCK-8) assay, colony formation assay and flow cytometry. After interference in the expression of NCK1-AS1, the expression of cyclin-dependent kinase 1 (CDK1) was determined using Western blotting. RESULTS: The results of qRT-PCR showed that the expression of NCK1-AS1 was up-regulated in 50 out of 64 cases of NSCLC tissues. It was found via statistical analysis that highly expressed NCK1-AS1 was positively correlated with tumor size, TNM stage and lymph node metastasis. The results of qRT-PCR revealed that the expression of NCK1-AS1 was also up-regulated in NSCLC cells. After interference in the expression of NCK1-AS1, the proliferation of NSCLC cells was inhibited, and the cell cycle was arrested at G2/M phase. The results of Western blotting manifested that the expression of CDK1 was suppressed after interference in the expression of NCK1-AS1. CONCLUSIONS: The expression of NCK1- AS1 is up-regulated in NSCLC, which indicates a poor prognosis. Highly expressed NCK1- AS1 promotes the proliferation of NSCLC cells through activating CDK1. [ABSTRACT FROM AUTHOR]

OBJECTIVE: We aimed to determine the expression level of long intergenic non-coding ribonucleic acid 1605 (LINC01605) in colorectal cancer (CRC), and to explore the effects of the LINC01605/microRNA (miR)-3960/sex-determining region Y-box 11 (SOX11) regulatory axis on the biological behaviors of CRC cells and the molecular mechanism therein. PATIENTS AND METHODS: Tissue specimens were collected from 38 patients with CRC, and the relative expression level of LINC01605 in the CRC tissues and CRC cells was measured using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Then, the effects of LINC01605 on the proliferation, apoptosis, invasion and metastasis of CRC cells were observed via in vitro assays [cell counting kit (CCK)-8 assay, flow cytometry and transwell assay]. Besides, the possible miRNAs binding to LINC01605 were predicted by the bioinformatics method, and they were screened and verified using qRT-PCR and Dual-Luciferase reporter gene assay. Finally, the downstream target genes of miR-3960 were predicted by means of bioinformatics, and they were also screened and confirmed via qRT-PCR and Dual-Luciferase reporter gene assay. RESULTS: According to the results of qRTPCR, the expression of LINC01605 was up-regulated in 31 out of 38 cases of CRC tissue specimens, and its expression in CRC cells was higher than that in normal colorectal cells. The results of in vitro assays revealed that the proliferation, migration and invasion abilities of CRC cells were weakened, with an increased apoptosis rate after interference with LINC01605 expression. Based on the results of qRT-PCR and Dual-Luciferase reporter gene assay, miR-3960 was the target of LINC01605, while SOX11 was the target of miR-3960. Moreover, the expression of miR-3960 rose, but that of SOX11 declined after interference with LINC01605 expression. It was found through Western blotting that the protein expression of SOX11 was lowered after interference with LINC01605 expression. CONCLUSIONS: LINC01605 has an up-regulated expression in CRC, and accelerates the proliferation, migration and metastasis of CRC cells by the miR-3960/SOX11 regulatory axis. [ABSTRACT FROM AUTHOR]

Barriers to continuous cropping of poplar plantations are closely related to the accumulation of phenolic acids in the soil. The purpose of this study was to explore the mechanism through which phenolic acid stress affects poplar productivity. The results showed that phenolic acids had a significant inhibitory effect on the photosynthesis of poplar. The inhibition of photosynthesis due to phenolic acids occurred mainly because, during electron transfer at the PSII reaction center, the primary quinone acceptor of PSII (QA) in the oxidized state was reduced, and excess light energy was lost in the form of heat dissipation; thus, poplar productivity decreased. At low phenolic acid concentrations (0X--1.5X), the activity of the PSII reaction center was temporarily inactivated, mainly because of stomatal limiting factors. At high phenolic acid concentrations (1.5X--3.0X), the PSII reaction centers were damaged, and photoinhibition occurred, mainly because of nonstomatal limiting factors. [ABSTRACT FROM AUTHOR]

Potassium tantalates, K2Ta2O6 and KTaO3, were synthesized by hydrothermal route. The crystal structural, optical, and adsorption properties of tantalates were investigated in the manuscript. The results indicate that the initial concentration of KOH is the determinate factor of crystal structure of tantalates. When the concentration of KOH is lower than 6M, the product is K2Ta2O6. While when the concentration is higher than 7M, the main product is KTaO3. Optical properties of tantalates analysis shows that the band gap of K2Ta2O6 is larger than that of KTaO3, which may be due to the different electronic band structure originating from the different overlapping way of the atomic orbital of tantalum and oxygen. The adsorption performance study shows that the adsorption property of K2Ta2O6 is higher than that of KTaO3, which would be assigned to its larger surface area. [ABSTRACT FROM AUTHOR]

The effect of nitrogen concentration on the interfacial and optical properties, as well as band offsets of HfTiO thin films by rf sputtering HfTi alloy target has been systematically investigated. The results indicate that an interfacial layer is unavoidably formed between HfTiON thin films and Si substrate, and the main content of the interfacial layer is silicate. No silicide is formed in the interfacial layer which is partly responsible for the poor electrical properties of high-k gate dielectrics. The optical properties of HfTiON films change, such as the refractive index decreases, while the extinction coefficient increases with the increase of N content, due to the defects increase in the films. The results also indicate that the bandgap and VB offset reduce with the introduction of N into HfTiO thin films. The CB offset of the HfTiON thin films is almost unchanged indicating that the N concentration has little effect on CB offset. However, the bandgap and band offsets are all higher than 1 eV, the sufficient band offsets still makes sputtering-derived HfTiON films by HfTi alloy target a promising high-k gate dielectric for future complementary metal oxide semiconductor technology. [ABSTRACT FROM AUTHOR]

Thickness-modulated optical dielectric constants and band alignments of HfOxNy films grown by sputtering have been investigated by spectroscopic ellipsometry (SE) and x-ray photoelectron spectroscopy. Based on SE measurements, it has been noted that an increase in optical dielectric constant and band gap has been observed as a function of the film thickness. Analyses of thickness-dependent band alignment of the HfOxNy/Si system indicate that the valence band offset increases, but only slight change in the conduction band offset, resulting from the thickness-induced change in the structure. The suitable optical dielectric constants and band offsets relative to Si make sputtering-derived HfOxNy film a promising candidate for high-k gate dielectrics. [ABSTRACT FROM AUTHOR]

Composition-dependent electronic structure and optical properties of Hf1-xSixOy (0.1≤x≤0.6) gate dielectrics on Si at 450 °C grown by UV-photo-induced chemical vapor deposition (UV-CVD) have been investigated via x-ray photoemission spectroscopy and spectroscopy ellipsometry (SE). By means of the chemical shifts in the Hf 4f, Si 2p, and O 1s spectra, the Hf–O–Si bondings in the as-deposited films have been confirmed. Analyses of composition-dependent band alignment of Hf1-xSixOy/Si gate stacks have shown that the valence band (VB) offset (ΔEv) demonstrates little change; however, the values of conduction band offset (ΔEc) increase with the increase in the silicon atomic composition, resulting from the increase in the separation between oxygen 2p orbital VB state and antibonding d states intermixed of Hf and Si. Analysis by SE, based on the Tauc–Lorentz model, has indicated that decreases in the optical dielectric constant and increase in band gap have been observed as a function of silicon contents. Changes in the complex dielectric functions and band gap Eg related to the silicon concentration in the films are discussed systematically. From the band offset and band gap viewpoint, these results suggest that Hf1-xSixOy films provide sufficient tunneling barriers for electrons and holes, making them promising candidates as alternative gate dielectrics. [ABSTRACT FROM AUTHOR]

High-k gate dielectric YOxNy films were prepared by reactive sputtering. The effects of postdeposition annealing on the structure and optical properties of YOxNy films have been investigated. The x-ray diffraction result shows that the crystallization starts at the annealing temperature of 500 °C. Spectroscopic ellipsometry was employed to determine the optical properties of a set of YOxNy films annealed at various temperatures. It was found that the refractive index (n) of YOxNy films decreased with the increase of annealing temperature below 600 °C, whereas it increased with increasing annealing temperature above 600 °C. The annealing-temperature dependence of the optical band gap of YOxNy films was also discussed in detail. It has indicated that the optical band gap of YOxNy films shifts to higher energy after higher temperature annealing, which is likely due to the reduction of N content and the change of crystalline structure in YOxNy films. [ABSTRACT FROM AUTHOR]

N-doped ZnO films were prepared by annealing zinc oxynitride films deposited by rf reactive sputtering. Two Raman peaks were observed at 274 and 580 cm-1. According to the variation of the integral intensity of these two peaks, the nitrogen activation at 500 °C [the activation temperature (AT)] has been obtained. Below the AT, the integral intensities of them show a different variation trend. X-ray photoelectron spectroscopy (XPS) indicates the N chemical state variation for them and finds the activated Zn-N bond. Further analyses by photoluminescence (PL) spectra and spectroscopic ellipsometry (SE) have been carried out. The activated sample exhibits a symmetric emission peak at 3.22 eV assigned to be the A0X emission at room temperature. SE investigation takes account of samples within the different temperature span divided by the AT. Different factors, such as nitrogen dopant (N)O and the nanocrystal growth, which affect the redshift of the absorption edges, have been discussed. [ABSTRACT FROM AUTHOR]

The structural stability and optical properties of ultrathin HfAlOx films grown by facing-target reactive sputtering, depending on the postannealing temperature, have been determined via x-ray photoelectron spectroscopy and spectroscopic ellipsometry (SE). By virtue of the chemical shifts of Hf4f, Al2p, and Si2p core-level spectra, it has been found that the structural stability of HfAlOx/Si system sustains up to 800 °C. However, the breaking of the Hf–Al–O bond and the phase separation take place drastically at the annealing temperature of 900 °C. In particular, the information of an interfacial Si–O–Si bond as the dominant reaction during the postannealing treatment has been observed, confirmed by Fourier transform infrared spectroscopy. Analysis by SE, based on the Tauc-Lorentz model, has indicated that increase in the refractive index and reduction in thickness has been observed as a function of annealing temperature, originating from the annealing-induced higher packing density. The change of the complex dielectric functions and bandgap Eg correlated with the annealing temperature are discussed in detail. [ABSTRACT FROM AUTHOR]

The microstructure and optical dielectric constants of HfOxNy thin films deposited by using radio frequency reactive magnetron sputtering have been investigated at various substrate temperatures. Fourier transform infrared spectroscopy spectra indicate that an interfacial layer has been formed between the Si substrate and the HfOxNy thin film during deposition. Spectroscopy ellipsometry (SE) results show that the substrate temperature has a strong effect on physical properties of HfOxNy thin films such as refractive index n and extinction coefficient k. Meanwhile, the optical dielectric functions of the films have determined using SE data and optical absorption properties of HfOxNy thin films deposited at different substrate temperatures have also been studied. [ABSTRACT FROM AUTHOR]

A high-k Hf-silicate interfacial layer grown by the solid phase reaction between sputtered metallic Hf films and an underlying SiO2/Si substrate through in situ vacuum annealing and subsequent thermal oxidation has been investigated. By means of the chemical shifts of Si 2p, Hf 4f, and O 1s core-level spectra determined by x-ray photoelectron spectroscopy (XPS), the formation of an interfacial Si-O-Si bond as the dominant reaction during in situ thermal oxidation of the Hf/SiO2/Si gate stack has been confirmed. In situ vacuum anneals without air exposure at 700 °C accelerates the interface reaction and results in the formation of Si-rich Hf-silicate interfacial layer. Analysis by Fourier transform infrared spectroscopy (FTIR) has indicated that vacuum annealed samples containing the silicate interface layer effectively suppresses the growth of the interfacial SiOx layer compared to unannealed samples during postdeposition annealing. [ABSTRACT FROM AUTHOR]

Rutile structured SnO[sub 2] nanobelts have been synthesized from the mixture of Sn powders and SiO[sub 2] nanoparticle powders. Each nanobelt has a uniform width of about several hundred nanometers and a thickness of about tens of nanometers along its entire length. Micro-Raman spectrum measurement on the SnO[sub 2] nanobelts shows that the first-order Raman A[sub 1g] mode (632.9 cm[sup -1]) is very strong, and two weak Raman bands 498 and 694 cm[sup -1] seem to correspond to infrared (IR)-active longitudinal optical (LO) and transverse optical (TO) of A[sub 2u] modes. In addition, the IR spectrum of the SnO[sub 2] nanobelts shows the A[sub 2u] (LO) (701.9 cm[sup -1]) and E[sub u (1)] (TO) (634.5 cm[sup -1]) modes and one surface mode (565.2 cm[sup -1]). The IR-active bands in the Raman spectrum and the surface mode in IR spectrum, which may be due to the nanoscale morphology of the nanobelts. [ABSTRACT FROM AUTHOR]

Studies ballistic electronic transport in a proposed mesoscopic structure, quantum cable. Uniqueness of the structure quantum cable for the study of mesoscopic transport; Correlation between Fermi energy of electrons and ballistic conductance of quantum cable; Impact of the accidental degeneracies of the transverse subbands of quantum cable on the quantum conductance units.

OBJECTIVE: JAK-STAT3 signaling pathway is related to tumor invasion and metastasis that can regulate matrix metalloproteninase-9 (MMP-9) expression. MicroRNA-124 (MiR-124) was found downregulated in renal cell carcinoma. Bioinformatics analysis revealed the complementary binding site between miR-124 and 3'-UTR of signal transducers and activators of transcription 3 (STAT3). This study investigated the role of miR-124 in regulating Janus kinase (JAK)-STAT3 activity, MMP-9 expression, and renal cell carcinoma invasion. MATERIALS AND METHODS: Luciferase assay was used to test the targeting regulatory effect of miR-124 on STAT3. MiR-124, STAT3, phosphorylated STAT3 (p-STAT3), and MMP-9 expressions were compared in HK-2, 769-P, and OS-RC-2 cells. Transwell assay was applied to evaluate cell invasion. OS-RC-2 cells were divided into control, miR-NC, miR-124 mimic, STAT3 inhibition, and miR-124 mimic+Stattic groups. RESULTS: MiR-124 targeted inhibited STAT3 expression. OS-RC-2 cells exhibited the strongest invasive ability, followed by 769-P and HK-2 cells. STAT3, p-STAT3, and MMP-9 expressions were highest in OS-RC-2 cells, followed by 769-P and HK-2 cells. MiR-124 demonstrated the opposite expression trend. MiR-124 mimic and/or Stattic treatment attenuated cell invasion through reducing STAT3, p-STAT3, and MMP-9 levels. CONCLUSIONS: MiR-124 down-regulation was associated with renal cancer cell OS-RC-2 invasion enhancement. Over-expression of miR-124 attenuated OS-RC-2 cell invasion by down-regulating STAT3 and MMP-9. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Janus kinase (JAK)-signal transducer and activator of transcription (STAT) signaling pathway participate in cell proliferation and apoptosis. Suppressors of cytokine signaling 3 (SOCS3) are negative regulators of JAK-STAT3. SOCS3 was found significantly declined, while microRNA-221 (miR-221) obviously up-regulated in bladder cancer tissue. Bioinformatics analysis revealed the complementary binding site between miR-221 and 3'- UTR of SOCS3. This study investigated the role of miR-221 in regulating SOCS3/JAK-STAT3 signaling pathway and bladder cancer cell proliferation and apoptosis. PATIENTS AND METHODS: Bladder cancer tumor tissue and para-carcinoma tissue were collected from patients to test miR-221 and SOCS3 expressions. Dual luciferase assay was used to test the targeting regulatory effect of miR-221 on SOCS3. MiR-221, SOCS3, p-JAK1, p-JAK2, and survivin expressions were compared in T24 and HBEC cells. T24 cells were divided into miR-NC, miR-221 inhibitor, pSicoR-blank, pSicoR-SOCS3, and miR-221 inhibitor + pSicoR-SOCS3 groups. Flow cytometry was applied to detect cell apoptosis. EdU staining was adopted to evaluate cell proliferation. RESULTS: MiR-221 significantly increased, while SOCS3 obviously reduced in bladder cancer tissue compared with para-carcinoma tissue. MiR-221 targeted inhibited SOCS3 expression. MiR-221, phosphorylated JAK1 (p-JAK1), phosphorylated JAK2 (p-JAK2), phosphorylated STAT3 (p-STAT3) and survivin levels markedly up-regulated, whereas SOCS3 expression apparently declined in T24 cells compared with that in HBEC cells. MiR-221 inhibitor and/or pSicoR- SOCS3 elevated SOCS3 expression, decreased p-JAK1, p-JAK2, p-STAT3 and survivin levels, enhanced cell apoptosis and attenuated cell proliferation. CONCLUSIONS: MiR-221 elevated, while SOCS3 reduced in bladder cancer tissue. Inhibition of miR-221 suppressed T24 cell proliferation and induced apoptosis by up-regulatingSOCS3 expression, lowering JAK-STAT3 signaling pathway activity and attenuating survivin expression. [ABSTRACT FROM AUTHOR]

Presents information on a study that investigated direct current resistivity and its temperature dependence for macrostructured NiAl. Types of defects in n-material; Two aspects in which the interaction of interfaces with the conduction electrons is manifested.

Alignment calibration of an inertial measurement unit (IMU) and Doppler sensors is a key factor that limits the accuracy of inertial navigation system (INS)/Doppler velocity log (DVL) integrated navigation. The commonly used methods in alignment calibration that need continuous externally-aided information are inconvenient for underwater vehicle applications. In this paper, we propose a simple and easy alignment calibration method, which only needs one additional position besides the initial position. Nevertheless, the DVL-aided INS initial alignment is still a challenge, as it impacts the accuracy of the proposed calibration method. Therefore, an attitude backtracking technique that can improve the calibration robustness is proposed. Experimental results show that the proposed method is able to eliminate the effects of the INS initial alignment and hence yield reliable calibration results. [ABSTRACT FROM AUTHOR]

Lasing characteristics of randomly assembled ZnS nanosheets are studied at room temperature. Under 266-nm optical excitation, sharp lasing peaks emitted at around 332 nm with a linewidth less than 0.4 nm are observed in all directions. In addition, the dependence of lasing threshold intensity with the excitation area is shown in good agreement with the random laser theory. Hence, it is verified that the lasing characteristics of randomly assembled ZnS nanosheets are attributed to coherent random lasing action. [ABSTRACT FROM AUTHOR]

We report a new route to synthesize nanosized (La0.67-XGdX)Sr0.33MnO3 (X=0.1,0.15) perovskite crystalline complex oxides at calcination temperatures of 600-900 °C using amorphous molecular alloy as precursor. The precursor could completely decompose into oxide at temperatures below 500 °C according to thermogravimetric analysis and differential thermal analysis results. X-ray diffraction demonstrated that the decomposed species was composed of perovskite structure at a calcination temperature of 600 °C for 2 h. The size and topography of the oxides are dependent on the calcination temperature of the precursor. The resulting particle size is in the range of 40-120 nm as determined by a transmission electron microscope. This method is effective and can be easily quantitatively controlled to synthesize nanosized perovskite complex oxides. The Curie temperature TC and the magnetocaloric effect of (La0.67-XGdX)Sr0.33MnO3 (X=0.1,0.15) nanoparticles are discussed based on the measurement of the low-field magnetization curve and the isothermal magnetization curve. [ABSTRACT FROM AUTHOR]

The morphology controlled growth of large area ordered porous film presents a number of challenges. This paper reports work on a universal route, 'solution dipping template strategy', for such structured films. The morphologies of the porous film can easily be controlled by concentration of the precursor solution and treatment conditions. By decreasing concentration from a high to a very low level, nanostructured complex (pore–hole, and pore–particle) arrays, through pore arrays, and even ring arrays can, in turn, be acquired. The pore size is adjustable over a range up to two orders of magnitude using the diameter of latex spheres. This new synthesis route is universal and can be used for metals, semiconductors, and compounds on any substrate. Such structures may be useful in applications in energy storage or conversion, especially in next generation integrated nanophotonics devices, biomolecular labelling and identification. [ABSTRACT FROM AUTHOR]