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Tip-enhanced Raman spectroscopy (TERS) combines inelastic light scattering well below the diffraction limit down to the nanometer range and scanning probe microscopy and, possibly, spectroscopy. In this way, topographic and spectroscopic as well as single- and two-particle information may simultaneously be collected. While single molecules can now be studied successfully, bulk solids are still not meaningfully accessible. It is the purpose of the work presented here to outline approaches toward this objective. We describe a home-built, liquid helium cooled, ultrahigh vacuum TERS. The setup is based on a scanning tunneling microscope and, as an innovation, an off-axis parabolic mirror having a high numerical aperture of ∼0.85 and a large working distance. The system is equipped with a fast load-lock chamber, a chamber for the in situ preparation of tips, substrates, and samples, and a TERS chamber. Base pressure and temperature in the TERS chamber were ∼3 × 10−11 mbar and 15 K, respectively. Polarization dependent tip-enhanced Raman spectra of the vibration modes of carbon nanotubes were successfully acquired at cryogenic temperature. The new features described here including very low pressure and temperature and the external access to the light polarizations, thus the selection rules, may pave the way toward the investigation of bulk and surface materials. [ABSTRACT FROM AUTHOR]

The increased susceptibility of MPXV-associated encephalitis in young children highlights the need for a high index of suspicion since early MPXV infections can be confused with other common viral infections (such as hand foot and mouth disease) in this age group. In total, there were seven cases of encephalitis, in which three patients died while two made a full recovery.[[2], [4], [6]] The youngest patient recorded was only 28 days at birth, while the oldest patient recorded was 43 years old. The human monkeypox virus (MPXV), a member of the Orthopoxvirus genus, causes monkeypox, a re-emerging zoonotic viral disease that has a similar but less severe clinical presentation to smallpox.[1] While MPXV is endemic in African countries, the most recent outbreak has seen it spread to several countries. [Extracted from the article]

There have been a fund of studies on Chinese Grammatical Error Correction (CGEC) since it was proposed by NLPCC 2018 shared task 2. In previous studies, most researchers regarded this task as a Neural Machine Translation (NMT) task, which treated erroneous sentences as source-language and correct sentences as target-language. But this method relies on large-scale parallel corpus. In recent years, Bidirectional Encoder Representations from Transformers (BERT) and its variants have made an exciting breakthrough on various NLP tasks and inspire NLP practitioners to explore the utilization of pre-trained model. However, BERT performs better on Natural Language Understanding (NLU) benchmarks (e.g., SQuAD v1.1), the applications on generative tasks are inadequate. In NLP-TEA CGED Shared Task 2020, many methods based on BERT Pre-trained model have emerged. Unlike CGED tasks, whose purpose is to detect error position and error types in a sentence, are usually regarded as sequence labelling or binary classification problem. CGEC is a sequence generation task. In this study, we leverage n-gram statistical language model as a spelling checker and BERTbased pre-trained model as the encoder in sequence-to-sequence (seq2seq) structure to solve CGEC problem. Our baseline is Transformer. The experimental results demonstrate that our method outperforms the other three participating teams but also some latest methods, and we analyze how different checkpoints affect our results. [ABSTRACT FROM AUTHOR]

Grain growth behaviors of niobium free, 0.021 wt. % niobium microalloyed and 0.024 wt. % niobium‐0.0022 wt. % boron microalloyed 20MnCr5 steels are investigated in this paper. Optical microscopy and field‐emission scanning electron microscopy were used to analyze the prior austenite grain. Transmission electron microscopy and energy dispersive spectroscopy were used to investigate the morphologies and compositions of the precipitates, respectively. The results show that adding niobium reduces the size of prior austenite grain. The addition of boron to niobium microalloyed steel, however, causes grain coarsening. Thermodynamic and kinetic calculations were performed to explain the mechanism of grain growth behavior. The results indicate that the addition of niobium and boron causes the difference in solution temperatures of aluminum nitride and niobium carbonitride precipitates. The addition of boron inhibits the precipitation of niobium carbonitride and aluminum nitride and causes precipitates coarsening. The precipitation observation backs up the calculation results. [ABSTRACT FROM AUTHOR]

The causes of corrosion failure of 20CrMnTi rusted gear were analyzed by quantitative analysis of the composition, observation of the microstructure, hardness test and electrochemical test. The microstructure characterization showed that the proportion of retained austenite in the rusted gear was slightly higher and the length‐width ratio of martensite on the surface of addendum of rusted gear was slightly larger than that of the normal gear. However, the corrosion resistance of the rusted gear surface was similar to that of the normal gear. The lubricating oil of the gear was detected to contain water molecules. Further investigation showed that continuous rainy days during the period from installation to disassembly led to a relatively high humidity environment and also the block cover was not installed at that time. Therefore, the corrosive medium continuously entered the gearbox through the block cover hole and destroyed the protection of lubricating oil film, resulting in serious erosion of the gear near the block cover hole. After securing the problem, the block cover was kept installed all the time and no such corrosion failure occurred again. [ABSTRACT FROM AUTHOR]

Based on the loading features of reinforced timber-concrete composite (TCC) beams, a calculation model of their ultimate flexural capacity is established. To verify calculation results, four TCC beams with different degrees of reinforcement were prepared and tested, and a good agreement between test data and calculations was found to exist. [ABSTRACT FROM AUTHOR]

GaN films with single-crystal and polycrystalline structure were deposited on (111) and (100) MgAl2O4 substrates by metalorganic chemical vapor deposition using a substrate modified by chemical etching and thermal passivation. The interface structure and chemical bonding state of the GaN/MgAl2O4 interface was investigated using angle-resolved x-ray photoelectron spectroscopy and resulting valence band spectra. Our results indicate that the Al2O3 buffered layer induced by thermal passivation of the (111) substrate remains unchanged during GaN deposition, which is primarily responsible for the epitaxial growth of GaN on (111) MgAl2O4 substrate. However, for the as-processed (100) substrate, interfacial reactions take place between the formed MgO-terminated surface and GaN films and GaN with a polycrystalline structure on (100) substrate forms. From the interface engineering viewpoint, the appropriate interface modification will allow control of the interface reaction to obtain high-quality GaN films for future optoelectronic devices. [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]

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]

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]

The kinetics of the glass transition and the crystallization behavior of Ti–Cu–Ni–Sn–M (M=Zr,Mo,Ta) glassy alloys were investigated by differential scanning calorimetry and x-ray diffraction. The glass-forming ability (GFA) of the glasses was analyzed in terms of the fragility concept and the width of the supercooled liquid region. The Ti-base glasses studied were found to have lower GFA than Zr, Pd, La, Fe, Mg-base bulk metallic glasses (BMGs), but to be comparative GFA to Ni- and Au-base BMGs. Higher Mo content or higher Ti–Ta content in the alloys lowers the GFA. The chemical complexity and multiphase crystallization requiring long-range atomic diffusion may contribute to the thermal stability of the supercooled liquid against crystallization. The products of crystallization of the glasses include bcc β-Ti(M) solid solution and Ti[sub 2]Ni and Ti[sub 2]Cu intermetallics. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The integrated-absorption coefficients of several hyperfine lines of the magnetic dipole allowed transition of the bromine atom, Br, center at 3685.2 cm[SUP-1] were measured, and a value for the square of the magnetic dipole transition moment of the Br atom was determined. A theoretical calculation for the magnetic dipole transition moment was also carried out using a relativistic ab initio atomic structure formulation. The theoretical value was in excellent agreement with the value predicted assuming pure LS coupling, and in reasonable agreement with experiment. The Br atom was generated in equal concentration with the cyano radical (CN) by the 193 nm photolysis of cyanogen bromine, BrCN. The CN radicals were titrated by the rapid reaction with C[SUB3]H[SUB8] to generate HCN and a small amount of HNC. Both time-resolved and frequency-scanned infrared absorption spectroscopy were used to monitor the Br, HCN, and HNC species. The photolysis of BrCN at 193 nm produced both the ground state Br([SUP2]P[SUB3/2]) and the spin-orbit excited Br([SUP2]P[SUB1/2]) atoms, and the yield for the production of Br([SUP2]P[SUB1/2]) atoms was measured to be 0.31_+ 0.01. The rate constants for the quenching of Br([SUP2]P[SUB1/2]) by BrCN and C[SUB3]H[SUB8] at 293 K were also determined. [ABSTRACT FROM AUTHOR]

Examines the electronic-vibrational transition moment for the (2,0) band of the cyano (CN) radical. Application of a direct time-resolved absorption technique; Line strength of the R[sub 1] transition; Formation of the CN radical from the pulsed-laser photolysis of cyanogen; Absorption features of CN and hydrogen cyanide.

Abstract We report for the first time the observation of irradiation-induced amorphization of the zirconium suboxide formed during aqueous corrosion of Zr-0.5Nb alloys. High-resolution transmission electron microscopy results reveal amorphization of the hexagonal-ZrO suboxide under heavy ion irradiation at cryogenic temperatures. This irradiation-induced amorphization behaviour is discussed in relation to the arrangement of oxygen interstitials and the formation of stable superlattices. The sensitivity of the suboxide to irradiation damage can lead to phase changes and the accumulation of defects near the oxide/metal interface, which needs to be taken into account in the development of mechanistic models addressing radiation-assisted acceleration of corrosion rates in zirconium alloys. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Abstract In this work, sputtering route has been pursued for the deposition of amorphous InGaZnO thin films under different oxygen partial pressure ratio (O ppr ). The effect of oxygen partial pressure ratio on the microstructure, optical and electrical properties and chemical bonding states of the sputtering-derived amorphous indium-gallium-zinc oxide (α-IGZO) thin films have been investigated by X-ray diffraction, X-ray photoelectron spectroscopy, UV–vis spectroscopy, and a series of electrical measurements. Measurements based on α-IGZO/SiO 2 thin film transistors (TFTs) have shown that oxygen partial pressure ratio can effectively regulate the carrier concentration, the defect trap density in the bulk channel and the interface between the channel and the gate insulator. The appropriate oxygen partial pressure ratio can reduce interface trap density (N it ) and decrease the off-state current (I off ), which can obviously improve the on/off current ratio (I on /I off ) and the stability of the device. In addition, the appropriate oxygen partial pressure ratio increases the overlap of the ns-orbit of metal ions in the film, which is conducive to improve the electronic transport routes and increase the carrier mobility. As a result, the optimized TFTs performance with oxygen partial pressure ratio of 6.3% has been achieved, including a high saturation mobility ( μ sat ) of 9.9 cm2V-1S−1, a large on/off current ratio of 3.5 × 109, a small subthreshold swing (SS) of 0.29 V/decade, a threshold voltage shift of 4 V under positive bias stress for 7200 s, respectively. A resistor loaded inverter was also constructed on α-IGZO/SiO 2 TFTs and exhibited full swing characteristics with a high gain of 10.3, which is sufficient to drive the next stage component in a logic circuit. All the experimental results have indicated that the sputtering-derived α-IGZO thin films have potential application in large-area all-oxide flexible electronics. Highlights • Sputtering-derived amorphous IGZO films were deposited on Si/SiO 2 substrate. • A resistor loaded inverter coupled with IGZO/SiO 2 TFTs was constructed. • The inverter exhibited full swing characteristics with a high gain of 10.3. [ABSTRACT FROM AUTHOR]

The microstructure, optical and electrical properties of sputtering-derived HfGdO high-k gate dielectric thin films as a function of the Gd doping content have been systematically investigated. X-ray diffraction (XRD) measurements have indicated that Gd doping can form a new stable cubic phase. The optical band gap of the HfGdO gate dielectrics increases gradually from 5.82 to 6.14 eV as the Gd doping concentration increases. The electrical properties, such as permittivity, oxide trapped charge density, border trap charge density and leakage current density of samples, are determined using a semiconductor device analyzer. The formation mechanism of leakage current is also discussed in detail. In addition, the interfacial properties of HfGdO/Si gate satcks were tested to establish the electrical properties. The excellent optoelectronic properties, such as the optical band gap of 5.95 eV, leakage current density of 8.33 × 10 −8 A/cm 2 at a bias voltage of 2 V, oxide trapped charge density of −1.06 × 10 12  cm −2 and a border trap charge density of zero and optimized interfacial properties were observed in the HfGdO thin films with sputtering power of 30 W, indicating that it may become a potential high-k gate dielectric in future complementary metal oxide semiconductor (CMOS) devices. [ABSTRACT FROM AUTHOR]

Microstructural characterization of the bainite in a ferritic-pearlitic forged crankshaft was carefully investigated. A Gleeble thermo-mechanical simulator as well as a high resolution dilatometer were also used to analyze the effect of cooling rate on the bainite formation and the bainite transformation mechanism in steels with different austenite grain sizes. Results show that the fine structure of the bainite mainly consists of bainitic ferrite and martensite. No segregations are found where bainite forms. Bainite tends to form in the slower cooled inner part of the crankshaft with an austenite grain size exceeding 100 mm. The formation of bainite is mainly affected by the austenite grain size as well as the cooling rate in the crankshaft studied. As the austenite grain size increases, ferrite start, pearlite finish and bainite finish temperatures are decreased. More bainite forms when bainite finish temperature decreases. The critical cooling rate of bainite transformation is increased from 0.34 °Cs-1 to 0.44 °C·s-1, if the maximum austenite grain size is refined from 216 mm to 100 mm. For ferritic-pearlitic crankshafts, or other bulky products, the elimination of bainite can be achieved through austenite grain refinement. [ABSTRACT FROM AUTHOR]

Presents information on a study that investigated solid phase epitaxy amorphous Sn[subx]Ge[sub1-x] films on strain relieved germanium films on silicon(001) substrates. Experimental procedure; Results and discussion on the study; Conclusions.

In this study, Y-doped HfO 2 (HYO) high-k gate dielectric thin films have been deposited on cleaned n-type Si wafers by using co-sputtering technique. Annealing temperature dependent structural, optical, interfacial and electrical properties of HYO have been systemically studied using the x-ray diffraction (XRD), ultraviolet–visible spectroscope (UV–Vis), spectroscopy ellipsometry (SE), x-ray photoelectron spectroscopy (XPS) and electrical measurements. Based on XRD measurements, it can be noted that cubic phase has been detected and remained while doping with yttrium element and annealing at high temperature. Optical analysis by SE indicates that incorporation of Y into HfO 2 can enlarge the band gap and decrease the refraction index of the samples. High temperature annealing leads to the formation of low-k SiO 2 layer and silicate. Electrical measurements have demonstrated that MOS capacitor based on HYO/Si gate stack annealed at 400 °C shows excellent electrical properties, such as high dielectric constant, low oxide charge density border trapped oxide charge density and leakage current density, which can be attributed to the increase in band gap and conduction band offset by Y incorporation. [ABSTRACT FROM AUTHOR]

Annealing temperature dependent microstructure, optical and electrical properties of sol-gel-deposited HfGdO high-k gate dielectric thin films on Si substrates are systematically investigated. X-ray spectroscopy (XPS) analyses have confirmed that the interfacial layer at HfGdO/Si interface is mainly silicate and the component increases with increasing the annealing temperature. Moreover, the band offsets for HfGdO/Si gate stack as a function of annealing temperature also have been determined. As a result, it can be noted that increase in valence band offset (Δ E v ) and reduction in conduction band offset (Δ E c ) have been detected. Electrical characterizations have indicated that higher annealing temperature effectively improves the electrical characteristics, such as the increased effective permittivity ( k ) and the decreased flat band voltage shift (Δ V fb ). However, due to the reduced Δ E c and the appearance of crystallization, increased leakage current density has been observed with the increase in annealing temperature. [ABSTRACT FROM AUTHOR]

By introducing a trigonal curve [ABSTRACT FROM AUTHOR]

The kinematical effect induced by the transversal motion of a gravitational lens on the frequency shift of light has been investigated in detail, while the effect of the radial motion is thought to be much smaller than the transversal one and thus has usually been neglected. In this work, we find that the radial velocity effect on the frequency shift has the same order of magnitude as that of the transversal velocity effect, when the light emitter (or the receiver) is close to the gravitational lens with the distance between them being an impact parameter scale. The significant velocity effect is usually transient due to the motion of the gravitational lens relative to the light emitter or the receiver. [ABSTRACT FROM AUTHOR]

The objective of the study was to evaluate the effects of incorporating plant protein blend in juvenile turbot ( Scophthalmus maximus L.) diet on free amino acid ( AA) concentration and the expression of genes related to peptide and AA transporters, key enzymes of AA metabolism and AA response ( AAR) pathway. Fish were fed diets with fish meal ( FM), or 400 g/kg FM replacement by plant protein blend for 9 weeks. Compared with the FM diet, PP40 diet did not affect plasma essential amino acid ( EAA) concentration or AA metabolic enzymes gene in intestine, while it significantly upregulated all the detected peptide and neutral AA transporters gene. Results in muscle indicated that PP40 diet led to a great reduction of EAA concentrations and mRNA abundance of two kinds of AA transporters ( SNAT2 and b0,+ AT), while it greatly increased the gene expression of L-type and T-type AA transporters ( LAT2 and TAT1) and the enzymes of AA catabolism ( BCKDH-E2) and anabolism (asparagine synthetase). In addition, the expression of genes related to AAR pathway were all greatly stimulated by PP40 diet in muscle. Our results provide a molecular explanation for the change of tissues AA concentrations caused by plant protein in turbot, which maybe applicable for general carnivorous fish. [ABSTRACT FROM AUTHOR]

The interaction of a swept shock wave and a supersonic wake has been studied. The swept shock wave is generated by a swept compression sidewall, and the supersonic wake is generated by a wake generator. The flow field is visualized with the nanoparticle-based planar laser scattering method, and a supplementary numerical simulation is conducted by solving the Reynolds-averaged Navier-Stokes equations. The results show that the pressure rise induced by the swept shock wave can propagate upstream in the wake, which makes the location where vortices are generated move upstream, thickens the laminar section of the wake, and enlarges the generated vortices. The wake is swept away from the swept compression sidewall by the pressure gradient of the swept shock wave. This pressure gradient is not aligned with the density gradient of the supersonic wake, so the baroclinic torque generates streamwise vorticity and changes the distribution of the spanwise vorticity. The wake shock is curved, so the flow downstream of it is non-uniform, leaving the swept shock wave being distorted. A three-dimensional Mach disk structure is generated when the wake shock interacts with the swept shock wave. [ABSTRACT FROM AUTHOR]

Supplementary information, such as multi-temporal spectral data and textural features, has the potential to improve land cover classification accuracy. However, given the larger volumes of remote sensing data, it is difficult to utilize all the features of remote sensing big data having different times and spatial resolutions. Inefficiency is also a large problem when dealing with large area land cover mapping. In this study, a new mode of incorporating spatial and temporal dependencies in a complex region employing the random forests (RFs) classifier was utilized. To map land covers, spring and autumn spectral images and their spectral indexes, textural features obtained from Landsat 5 were selected, and an importance measure variable was used to reduce the data's dimension. In addition to randomly selecting the variable, we used random sampling to furthest decrease the generalization error in RF. The results showed that utilizing random sampling, multi-temporal spectral image and texture features, the classification of the Wuhan urban agglomeration, China, using RF performed well. The RF algorithm yielded an overall accuracy of 89.2% and a Kappa statistic of 0.8522, indicating high model performance. In addition, the variable importance measures demonstrated that the type of textural features was extremely important for intra-class separability. The RF model has transitivity. The algorithm can be extended by choosing a set of appropriate features for signature extension over large areas or in time-series of Landsat imagery. Land cover mapping might be more economical and efficient if no-cost imagery is used. [ABSTRACT FROM AUTHOR]

Effects of nitrogen incorporation on the interface chemical bonding states, band alignment and electrical properties of sputtering-derived HfTiO high-k gate stacks on Ge substrates pretreated by trimethylaluminum (TMA) precursor have been investigated by X-ray photoemission spectroscopy (XPS), UV–vis transmission spectroscopy, and electrical measurements. XPS results indicate that incorporation of a moderate amount of nitrogen (3 sccm) incorporation can effectively suppress the formation of unstable GeO 2 and low-k germinate at the interfacial region. Meanwhile, reduction in band gap and valence band offset and increase in conduction band offset have been observed after nitrogen incorporation. Electrical properties were evaluated by capacitance-voltage ( C–V ) and leakage current density-voltage ( J–V ) measurements based on MOS capacitors. Small gate leakage current (4.13 × 10 −7 A/cm 2 at V g = 1 V), almost disappeared hysteresis, and large dielectric constant (19.6) that have been observed for MOS capacitor with HfTiON/Ge stacked gate dielectric with N 2 flow of 3 sccm. [ABSTRACT FROM AUTHOR]

In this work, the interface chemistry and the reduction of GaAs surface species by using (NH 4 ) 2 S solution prior to Gd-doped HfO 2 (HGO) thin film deposition and the removal of Ga Oxides and elemental As by rapid thermal annealing (RTA) have been investigated by X-ray photoelectron spectroscopy (XPS). Additionally, the effect of the surface passivation and rapid thermal annealing on the electrical properties of MOS capacitors based on sputtering-derived HGO as gate dielectric on GaAs substrate has been detected by means of capacitance-voltage ( C-V ) and leakage current density-voltage ( J-V ) measurements. Based on electrical analysis, it can be noted that the constantly improvement of electrical properties, such as the decreases of flat band voltage (V fb ), hysteresis (ΔV fb ), oxide charge density (O ox ), border trapped oxide charge density (N bt ) and leakage current density, have been observed. Especially, the dielectric constant of 16.72, flat band voltage V fb of 1.19 V, hysteresis ΔV fb of 0.04 V, leakage current density of 1.54 × 10 −5 A/cm 2 at bias voltage of 1 V, total positive charge density and border trap charge density of 6.09 × 10 12 cm −2 and 2.54 × 10 11 cm −2 , respectively render 600 °C-annealed HGO thin films, potential high-k gate dielectrics in future CMOS devices. [ABSTRACT FROM AUTHOR]

Regulating mechanisms underlying hepatic myeloid-derived suppressor cell (MDSC) accumulation remain to be described. Here, we provide evidence for the involvement of tumour-activated liver stromal cells in the process of hepatic MDSCs migration and accumulation. Our data showed an elevated frequency of MDSCs in the liver of tumour-bearing mice. Moreover, tumour-activated liver stromal cells promote MDSC migration into the liver site. Further investigation indicated higher levels of cytokine and chemokine expression in liver stromal cells after exposure to the tumour-conditioned supernatant. Notably, the expression levels of proinflammatory factors, mainly including macrophage colony stimulating factor (M-CSF), transforming growth factor-β (TGF-β), monocyte chemotactic protein-1 (MCP-1) and stromal-derived factor-1 (SDF-1), increased after treatment with tumour-conditioned supernatant, and blockade of MCP-1 or SDF-1 decreased the proportion of tumour infiltrated MDSCs in mice co-transplanted with liver stromal cells and tumour cells, but not in mice with only tumour cells injection. These findings demonstrate that tumour-activated liver stromal cells produce higher levels of chemokines and cytokines, which may contribute to MDSC accumulation into the liver site in patients with liver cancer. [ABSTRACT FROM AUTHOR]

In this work, the band gap, interfacial properties and electrical properties of Gd doped ZrO 2 high-k gate dielectric films deposited by solution method have been systematically investigated. Results have shown that Gd doping can increase band gap energy from 5.65 to 5.92 eV and effectively restrain the formation of low-k SiO x interfacial layer between dielectric and Si substrate. Moreover, the conduction band offset is increased from 2.57 to 3.06 eV by Gd doping, which effectively reduces the leakage current density to 1.8 × 10 −6 A/cm 2 . [ABSTRACT FROM AUTHOR]

HfAlO/Ge gate stack with Al 2 O 3 passivation layer and different Al 2 O 3 concentration in HfAlO layer has been deposited on Ge substrate by atomic layer deposition. Based on measurements from capacitance-voltage and current density-voltage curves, the evolution of the electrical properties of Ge-based MOS capacitors based on HfAlO/Al 2 O 3 /Ge gate stack has been determined as functions of precursor ratio and annealing temperature. It has been found that high annealing temperature and high Al 2 O 3 incorporation in HfAlO films can obtain improved electrical properties such as low hysteresis, low flat-band, low flat-band shift and low interface-state density. However, the oxide-charge density obviously increases with rising the annealing temperature and decreasing Al 2 O 3 incorporation in HfAlO film. By analysis and calculation, it can be noted that the samples annealed at 500 °C holds the lowest leakage current density and the change of the precursor ratio has no apparent effect in 500 °C-annealed Ge MOS capacitor. To investigate current conduction mechanism of Ge MOS capacitors employing HfAlO/Al 2 O 3 gate stacks, current density-voltage measurements have been carried out as functions of annealing temperature and precursor ratio. The involved leakage current conduction mechanisms of the as-deposited and 500 °C-annealed HfAlO/Al 2 O 3 /Ge MOS capacitors for substrate injection also have been discussed in detail. [ABSTRACT FROM AUTHOR]

Effects of nitrogen incorporation on the interfacial chemical bonding states, band alignment, electrical properties and leakage current conduction mechanisms of HfGdO-based metal-oxide-semiconductor (MOS) capacitors has been investigated by UV–Vis transmission spectroscopy, X-ray photoemission spectroscopy (XPS), and electrical measurements. XPS results indicate that incorporation of a moderate amount of nitrogen incorporation into HfGdO gate dielectrics can effectively suppress the formation of low- k GeO 2 and Hf(Gd)-Ge-O interfacial layer at the interfacial region. Meanwhile, reduction in band gap and valence band offset and increase in conduction band offset have been observed after nitrogen incorporation. Electrical measurements based on MOS capacitors have shown that MOS capacitor with HfGdON/Ge stacked gate dielectric with N 2 flow rate of 3 sccm exhibits small gate leakage current (1.08 × 10 −3 A/cm 2 at V g = 1 V), almost disappeared hysteresis, and large dielectric constant (29.2). The involved leakage current conduction mechanisms for MOS capacitor devices with and without nitrogen incorporation also have been discussed in detail. [ABSTRACT FROM AUTHOR]

Deposition of HfAlO x gate dielectric films on n-type Si and quartz substrates by sol-gel technique has been performed and the optical, electrical characteristics of the as-deposited HfAlO x thin films as a function of annealing temperature have been investigated. The optical properties of HfAlO x thin films related to annealing temperature are investigated by ultraviolet-visible spectroscopy (UV–vis) and spectroscopy ellipsometry (SE). By measurement of UV–vis, average transmission of all the HfAlO x samples are about 85% owing to their uniform composition. And the increase in band gap has been observed with the increase of annealing temperature. Moreover, the increase of refractive index (n) and density with the increase of annealing temperature are obtained by SE measurements. Additionally, the electrical properties based on Al/Si/HfAlO x /Al capacitor are analyzed by means of the high frequency capacitance-voltage ( C-V ) and the leakage current density-voltage ( J-V ) characteristics. Results have shown that 400 °C-annealed sample demonstrates good electrical performance, including larger dielectric constant of 12.93 and lower leakage current density of 3.75×10 −7 A/cm 2 at the gate voltage of 1 V. Additionally, the leakage current conduction mechanisms as functions of annealing temperatures are also discussed systematically. [ABSTRACT FROM AUTHOR]

In current work, effects of rapid thermal annealing on the interface chemical bonding states, band alignment, and electrical properties of atomic-layer-deposition-derived HfAlO/Al 2 O 3 gate stack on Si substrates have been studied by X-ray photoemission spectroscopy (XPS), UV–Vis transmission spectroscopy, and electrical measurements. XPS analyses have shown that HfAlO alloy and mixed silicate (Hf-Al-O-Si) increase after post-deposition annealing process. By means of UV–Vis transmission spectroscopy measurements, reduction in band gap for 400 o C-annealed sample has been observed. Accordingly, reduction in the valence band offset and increase in the conduction band offset have been detected for HfAlO/Al 2 O 3 /Si gate stack annealed at 400 °C. Various current conduction mechanisms, such as Poole-Frenkel emission, Fowler-Nordheim (FN) tunneling, and space-charge-limited (SCL) conduction, have been analyzed. Detailed electrical measurements reveal that current conduct mechanisms is SCL conduction at lower field region and FN tunneling and SCL conduction are dominant conduction mechanism at higher field region. [ABSTRACT FROM AUTHOR]

In this letter, annealing temperature dependence on the structure, band gap energy and electrical properties of TiO 2 doped ZrO 2 gate dielectrics deposited by sol-gel method at low temperature were systemically investigated. The crystalline temperature of TiO 2 doped ZrO 2 is up to 600 °C. The transmittance and band gap value of the ZrTiO x film were about 75% and 4.0 eV, respectively. 300 °C-annealed ZrTiO x MOS capacitor with high dielectric constant of 34.9, a small hysteresis value of 0.004 and low leakage current density of 2.7 × 10 −4 A/cm 2 were obtained. The dominant conduction mechanisms of Al/ZrTiO 4 / n -Si MOS structures were schottky emission and ohmic conduction in the low electric field and direct tunneling in the high electric field. As a result, it can be concluded that sol-gel derived ZrTiO x gate dielectric displays potential application as is a promising candidate in future MOS electronic devices. [ABSTRACT FROM AUTHOR]

Deposition of HfTiO x gate dielectric films on n-type Si and quartz substrates by sol–gel technique has been performed and the optical, electrical characteristics of the as-deposited HfTiO x thin films as a function of baking temperature have been investigated. The components and optical properties of HfTiO x thin films related to baking temperature are investigated by energy dispersive spectrometer (EDS), ultraviolet–visible spectroscopy (UV–Vis), and spectroscopy ellipsometry (SE). By measurement of EDS, the Hf/Ti molar ratio of HfTiO x thin films is calculated to be about 1:1.20 at all baking temperature. The increase in band gap is observed with the increase of baking temperature. Additionally, the electrical properties based on Al/Si/HfTiO x /Al capacitor are analyzed by means of the high frequency capacitance-voltage ( C-V ) and the leakage current density-voltage ( J-V ) characteristics. Results have shown that 200 °C-baked sample demonstrates good electrical performance, including larger dielectric constant of 23.31 and lower leakage current density of 5.12 × 10 −5 A/cm 2 at the gate voltage of 1 V. Additionally, the leakage current conduction mechanisms as functions of baking temperatures are also discussed systematically. [ABSTRACT FROM AUTHOR]

Background: MiR-214 is aberrantly regulated in several tumours, but its underlying mechanisms in colorectal cancer (CRC) metastasis remain largely unknown. This study aimed to demonstrate the function and potential mechanism of miR-214 in regulating invasion and metastasis of CRC.Methods: The transcription factor and targets of miR-214 were predicted by bioinformatics and validated using ChIP and dual-luciferase reporter assay. DNA methylation status was explored using bisulphite sequencing PCR. The in vitro and in vivo function of miR-214 in CRC was evaluated using MTT, plate colony formation, Matrigel invasion and animal models. Real-time PCR or western blotting was performed to detect FOXD3, miR-214 and MED19 expressions in CRC cells and clinical specimens.Results: MiR-214 was downregulated in CRC and was significantly correlated with lymphatic metastasis. Downregulation of miR-214 might due to promoter hypermethylation in CRC. FOXD3 was validated as a transcription factor of miR-214 by ChIP assay. Dual-luciferase assay identified MED19 as a target of miR-214 in CRC. In vitro and in vivo experiments showed that miR-214 mediated the inhibiting effect of FOXD3 on proliferation, invasion and metastasis by targeting MED19. Spearman's correlation analysis showed a positive correlation between FOXD3 and miR-214, and negative correlations between FOXD3 and MED19, miR-214 and MED19 in CRC cells and clinical specimens.Conclusions: FOXD3/miR-214/MED19 axis is important for the regulation of growth, invasion and metastasis of CRC. Targeting the miR-214-mediated axis might be helpful for the treatment of CRC. [ABSTRACT FROM AUTHOR]

We demonstrate a novel form of thermally-assisted hysteresis in the transfer curves of monolayer MoS2 FETs, characterized by the appearance of a large gate-voltage window and distinct current levels that differ by a factor of ∼10². The hysteresis emerges for temperatures in excess of 400 K and, from studies in which the gate-voltage sweep parameters are varied, appears to be related to charge injection into the SiO2 gate dielectric. The thermally-assisted memory is strongly suppressed in equivalent measurements performed on bilayer transistors, suggesting that weak screening in the monolayer system plays a vital role in generating its strongly sensitive response to the charge-injection process. By exploiting the full features of the hysteretic transfer curves, programmable memory operation is demonstrated. The essential principles demonstrated here point the way to a new class of thermally assisted memories based on atomically thin two-dimensional semiconductors. [ABSTRACT FROM AUTHOR]

Nanostructured soft materials open up new opportunities in material design and application, and block copolymer self-assembly is one particularly powerful phenomenon that can be exploited for their synthesis. The advent of controlled/living radical polymerisation (CLRP) has greatly simplified block copolymer synthesis, and versatility towards monomer types and polymer architectures across the different forms of CLRP has vastly expanded the range of functional materials accessible. CLRP-controlled synthesis of block copolymers has been applied in heterogeneous systems, motivated by the numerous process advantages and the position of emulsion polymerisation at the forefront of industrial latex synthesis. In addition to the inherent environmental advantages of heterogeneous routes, the incidence of block copolymer self-assembly within dispersed particles during polymerisation leads to novel nanostructured materials that offer enticing prospects for entirely new applications of block copolymers. Here, we review the range of block copolymers prepared by heterogeneous CLRP techniques, evaluate the methods applied to maximise purity of the products, and summarise the unique nanoscale morphologies resulting from in situ self-assembly, before discussing future opportunities within the field. [ABSTRACT FROM AUTHOR]

High- k HfO x N y and HfO 2 have been applied to amorphous InGaZnO ( a -IGZO) metal–oxide–semiconductor (MOS) capacitors as high-k gate dielectrics by using radio-frequency sputtering at room temperature. Effects of nitrogen incorporation on the optical band gap, band alignment and electrical properties of HfO x N y /IGZO/Si gate stacks have been systematically investigated by spectroscopic ellipsometry (SE), UV–vis spectroscopy, x-ray photoemission spectroscopy (XPS) and electrical measurements. Experimental results have confirmed the successful incorporation of nitrogen into HfO 2 films and reduction in band gap with the incorporation of nitrogen for HfO x N y thin films. Reduction in valence band offset and increase in conduction band offset have been observed for HfO x N y /IGZO gate stack. Electrical properties measurements for a -IGZO MOS capacitors based on HfO x N y gate dielectrics have indicated that nitrogen incorporation leads to the improved interface quality, increased dielectric constant, reduced hysteresis voltage, and decreased leakage current density. Meanwhile, the leakage current mechanism under gate injection for MOS capacitors based on HfO 2 and HfO x N y high-k gate dielectrics has been investigated systematically. [ABSTRACT FROM AUTHOR]

The microstructure, optical and electrical properties of HfTiO high-k gate dielectric thin films deposited on Si substrate and quartz substrate by RF magnetron sputtering have been investigated. Based on analysis from x-ray diffraction (XRD) measurements, it has been found that the as-deposited HfTiO films remain amorphous regardless of the working gas pressure. Meanwhile, combined with characterization of ultraviolet-visible spectroscopy (UV–vis) and spectroscopy ellipsometry (SE), the deposition rate, band gap and optical properties of sputtered HfTiO gate dielectrics were determined. Besides, by means of the characteristic curves of high frequency capacitance–voltage ( C – V ) and leakage current density–voltage ( J – V ), the electrical parameters, such as permittivity, total positive charge density, border trap charge density, and leakage current density, have been obtained. The leakage current mechanisms are also discussed. The energy band gap of 3.70 eV, leakage current density of 1.39×10 −5 A/cm 2 at bias voltage of 2 V, and total positive charge density and border trap charge density of 9.16×10 11 cm −2 and 1.3×10 11 cm −2 , respectively render HfTiO thin films deposited at 0.6 Pa, potential high-k gate dielectrics in future CMOS devices. [ABSTRACT FROM AUTHOR]

Fishmeal could only be replaced by plant proteins at limited levels in aquafeeds, especially for carnivorous fish. In this study, an experiment was designed to evaluate the possibility of improving the utilization of plant proteins by maggot meal supplementation in turbot diet. Five diets were formulated: a reference diet (FM) containing 63% fishmeal and four experimental diets (35(0%), 35(3%), 40 (0%), 40(3%)) in which fishmeal was substituted at different levels by plant proteins with 0-3% maggot meal. Turbot (4.90 0.03 g) was fed with these diets for 9 weeks. Fishmeal was successfully replaced by plant proteins in turbot diet without growth reduction at 35% but not 40%. However, maggot supplementation (3%) at 40% plant protein replacement level achieved comparable growth performance with that of fishmeal. Maggot meal supplementation improved apparent digestibility coefficients, plasma hydroxyproline levels, intestine trypsin activities and activated target of rapamycin (TOR) signalling, all of which were decreased or down-regulated after high plant protein replacement. Therefore, this study demonstrated maggot meal, a potential valuable protein source for turbot. [ABSTRACT FROM AUTHOR]

Uridine 5′-diphosphate-5-fluorogalactopyranose (UDP-5F-Galp, 7) was synthesized, and its effect on UDP-Galp mutase (UGM) was investigated. UGM facilitated the hydrolysis of 7 to yield UDP and 5-oxogalactose (24), but no 11 was detected. 19F NMR and trapping experiments demonstrated that the reaction involves the initial formation of a substrate-cofactor adduct followed by decomposition of the resulting C5 gem-fluorohydrin to generate a 5-oxo intermediate (10). The results support the current mechanistic proposal for UGM and suggest new directions for designing mechanism-based inhibitors. [ABSTRACT FROM AUTHOR]

Liquid is a promising candidate for terahertz radiation induced by femtosecond laser pulses, since it has advantages of higher molecular density, lower ionization potential and better self-healing properties compared with gases. In this work, an enhancement of terahertz radiation from saccharide solutions induced by femtosecond laser pulses is demonstrated, and the characteristics of terahertz radiation from saccharide solutions of different types and concentrations are investigated. It shows that terahertz radiant power from a glucose solution is 2 times higher than that from liquid water under the same excitation conditions. Among all the saccharide solutions studied, polysaccharides radiate the most powerful terahertz pulses and monosaccharides show the weakest radiation. The optimal solution concentrations of polysaccharide and disaccharide for terahertz radiation are 5 and 30%, respectively. As for monosaccharide solutions, when the concentration of the solution increases in the range of 0–30%, the power of terahertz radiation increases. In addition, quantum chemical calculations are carried out in this study to help explain the mechanisms for terahertz radiation from saccharide solutions. It is demonstrated that the power of terahertz radiation from saccharide solutions is roughly positively correlated with molecular qualities, densities, and viscosities of saccharide solutions, while negatively correlated with the band gap. [ABSTRACT FROM AUTHOR]

The effect of oxygen partial pressure on the microstructure, wettability, optical and electrical properties of sputtering-derived HfO 2 thin films has been systematically investigated by using x-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), atomic force microscope (AFM), UV–visible spectroscopy (UV–Vis), spectroscopy ellipsometry (SE), and electrical measurements. XRD results have shown that the HfO 2 thin films are all polycrystalline with monoclinic phase. Based on analysis from FTIR, a strong absorption peak centered at 1105 cm −1 has been detected, indicating the formation of the interfacial layer. Reduction in particle size and decrease in root mean square (RMS) roughness of the HfO 2 thin films have been detected by SEM and AFM measurements with the increase in oxygen partial pressure. Meanwhile, the contact angle decreases and the wettability increases with increasing the oxygen partial pressure. Combined with UV–vis and SE, the optical function of HfO 2 thin films as functions of oxygen partial pressure has been determined. By means of electrical measurements, evolution of electrical performance of MOS capacitor based on HfO 2 gate dielectrics related with oxygen partial pressure has been investigated systematically. [ABSTRACT FROM AUTHOR]

Background: Colorectal cancer (CRC) is one of the most common cancers in the world. MicroRNAs play important roles in the progression of CRC. This study aimed to investigate the role of miR-206 and its novel mechanism in the invasion and metastasis of CRC. Methodology: Real-time RT-PCR or Western blotting was used to detect the expressions of miR-206, FMNL2 and c-MET in CRC cell lines and tissues. Luciferase reporter assays were conducted to detect the associations between miR-206 and 3′UTRs of FMNL2 and c-MET. A series of loss-of-function and gain-of-function assays were performed to evaluate the effect of miR-206 on the proliferation, invasion and metastasis of CRC cells. Results: miR-206 was significantly down-regulated in CRC tissues and correlated closely with differentiation, lymphatic metastasis and serosal invasion. miR-206 suppressed CRC cell proliferation by arresting CRC cells in the G1/G0 phase and accelerating apoptosis. miR-206 also inhibited cell invasion and lung metastasis in CRC cells. Mechanically, FMNL2 and c-MET were identified as direct targets of miR-206. And FMNL2 rescued the suppression of miR-206 in the proliferation and invasion of CRC cells. Conclusions: This study revealed functional and mechanistic links between miR-206 and oncogene FMNL2 and c-MET in the progression of CRC. miR-206 functioned as a tumor suppressor in the progression of CRC by targeting FMNL2 and c-MET. Restoration of miR-206 expression may represent a promising therapeutic approach for targeting malignant CRC. [ABSTRACT FROM AUTHOR]

High-k gate dielectric HfTiO x thin films have been deposited on Si and quartz substrate by radio frequency (RF) magnetron sputtering. The structural and optical properties of HfTiO x thin films related to deposition power are investigated by X-ray diffraction (XRD), ultraviolet–visible spectroscopy (UV–Vis), and spectroscopic ellipsometry (SE). Results indicate that the as-deposited HfTiO x thin films are amorphous state regardless of the deposition power. The increase of band gap of the samples is observed with the increase of deposition power. Moreover, the increase of the thickness, deposition rate, refractive index (n) and the decrease of the extinction coefficient with the increase of deposition power are also confirmed. Additionally, the electrical properties of films are analyzed by measurement of high frequency capacitance–voltage ( C–V ) and leakage current density-voltage ( J-V ) characteristics. And the leakage current conduction mechanisms are also discussed. [ABSTRACT FROM AUTHOR]

The effect of boron (B) doping on the microstructure, band gap energy and electrical properties of ZrO 2 gate dielectrics deposited by sol–gel method at low temperature were systemically investigated. By means of characterization of spectroscopy ellipsometry and ultraviolet–visible spectroscopy, the thicknesses and optical constants of ZrO 2 gate dielectrics have been determined precisely. The B incorporation dependent electrical properties of ZrO 2 films were determined by capacitance–voltage ( C–V ) and leakage current density–voltage ( J–V ) measurements. The dominant conduction mechanisms of Al/B:ZrO 2 / n -Si MOS structures have been discussed systematically in detail. As a result, the optimized B incorporation content has been obtained to achieve ZrO 2 gate dielectrics with high quality. [ABSTRACT FROM AUTHOR]

Current conduction mechanisms of Hf 1−x Ti x O 2 -gated metal–oxide–semiconductor (MOS) capacitors depending on various post-annealing temperature (PDA) have been investigated. The sample subjected to 400 °C annealing exhibits superior performance with negligible hysteresis memory window shift (ΔV fb = 0.005 V) and lowest gate leakage current density (5.4 × 10 −5 A/cm −2 at V g = 2 V). In addition, evolution of density of interface traps ( D it ), border charger density (N ot ) and oxide charge density (Q ox ) as a function of annealing temperature were investigated in details. Detailed electrical measurements reveal that the dominant current conduction behaviors are Poole–Frankel (P–F) emission in the region of low electric fields and Schottky Emission (SE) in the region of high electric fields for gate injection. For substrate injection, however, is mainly via Ohm's conduction, Schottky emission (SE) conduction mechanism serves in low applied field in the samples, respectively. [ABSTRACT FROM AUTHOR]