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Most cases of hepatocellular carcinoma (HCC) arise with the fibrotic microenvironment where hepatic stellate cells (HSCs) and carcinoma-associated fibroblasts (CAFs) are critical components in HCC progression. Therefore, CAF normalization could be a feasible therapy for HCC. Galectin-1 (Gal-1), a β-galactoside-binding lectin, is critical for HSC activation and liver fibrosis. However, few studies has evaluated the pathological role of Gal-1 in HCC stroma and its role in hepatic CAF is unclear. Here we showed that Gal-1 mainly expressed in HCC stroma, but not cancer cells. High expression of Gal-1 is correlated with CAF markers and poor prognoses of HCC patients. In co-culture systems, targeting Gal-1 in CAFs or HSCs, using small hairpin (sh)RNAs or an therapeutic inhibitor (LLS30), downregulated plasminogen activator inhibitor-2 (PAI-2) production which suppressed cancer stem-like cell properties and invasion ability of HCC in a paracrine manner. The Gal-1-targeting effect was mediated by increased a disintegrin and metalloprotease 17 (ADAM17)-dependent TNF-receptor 1 (TNFR1) shedding/cleavage which inhibited the TNF-α → JNK → c-Jun/ATF2 signaling axis of pro-inflammatory gene transcription. Silencing Gal-1 in CAFs inhibited CAF-augmented HCC progression and reprogrammed the CAF-mediated inflammatory responses in a co-injection xenograft model. Taken together, the findings uncover a crucial role of Gal-1 in CAFs that orchestrates an inflammatory CSC niche supporting HCC progression and demonstrate that targeting Gal-1 could be a potential therapy for fibrosis-related HCC.

Galectin-1 (Gal-1) is a pleiotropic homodimeric β-galactoside-binding protein with a single carbohydrate recognition domain. It has been implicated in several biological processes that are important during tumor progression. Several lines of evidence have indicated that Gal-1 is involved in cancer immune escape and induces T cell apoptosis. These observations all emphasized Gal-1 as a novel target for cancer immunotherapy. Here, we developed a novel Gal-1-targeting DNA aptamer (AP-74 M-545) and demonstrated its antitumor effect by restoring immune function. AP-74 M-545 binds to Gal-1 with high affinity. AP-74 M-545 targets tumors in murine tumor models but suppresses tumor growth only in immunocompetent C57BL/6 mice, not in immunocompromised non-obese diabetic (NOD)/severe combined immunodeficiency (SCID) mice. Immunohistochemistry revealed increased CD4+ and CD8+ T cells in AP-74 M-545-treated tumor tissues. AP-74 M-545 suppresses T cell apoptosis by blocking the binding of Gal-1 to CD45, the main receptor and apoptosis mediator of Gal-1 on T cells. Collectively, our data suggest that the Gal-1 aptamer suppresses tumor growth by blocking the interaction between Gal-1 and CD45 to rescue T cells from apoptosis and restores T cell-mediated immunity. These results indicate that AP-74 M-545 may be a potential strategy for cancer immunotherapy., Graphical Abstract

The raised source/drain (RSD) structure is one of thin film transistor designs that is often used to improve device characteristics. Many studies have mentioned that the high impact ionization rate occurring at a drain side can be reduced, owing to a raised source/drain area that can disperse the drain electric field. In this study, we will discuss how the electric field at the drain side of an RSD device is reduced by a vertical lightly doped drain (LDD) scheme rather than a RSD structure. We used different raised source/drain forms to simulate the drain side electric field for each device, as well as their output characteristics, using Integrated Systems Engineering (ISE-TCAD) simulators. Different source and drain thicknesses and doping profiles were applied to verify the RSD mechanism. We found that the electric fields of a traditional device and uniform doping RSD structures are almost the same (~2.9 × 105 V/cm). The maximum drain electric field could be reduced to ~2 × 105 V/cm if a vertical lightly doped drain RSD scheme was adopted. A pure raised source/drain structure did not benefit the device characteristics if a vertical lightly doped drain design was not included in the raised source/drain areas.

The loss of cancer-cell junctions and escape from the primary-tumor microenvironment are hallmarks of metastasis. A tight-junction protein, Claudin 1 (CLDN1), is a metastasis suppressor in lung adenocarcinoma. However, as a metastasis suppressor, the underlying molecular mechanisms of CLDN1 has not been well studied. Methods: The signaling pathway regulated by CLDN1 was analyzed by Metacore software and validated by immunoblots. The effect of the CLDN1-EPHB6-ERK-SLUG axis on the formation of cancer stem-like cells, drug resistance and metastasis were evaluated by sphere assay, aldefluor assay, flow cytometry, migration assay, cytotoxicity, soft agar assay, immunoprecipitation assay and xenograft experiments. Furthermore, the methylation-specific PCR, pyrosequencing assay, chromatin immunoprecipitation and reporter assay were used to study the epigenetic and RUNX3-mediated CLDN1 transcription. Finally, the molecular signatures of RUNX3/CLDN1/SLUG were used to evaluate the correlation with overall survival by using gene expression omnibus (GEO) data. Results: We demonstrated that CLDN1 repressed cancer progression via a feedback loop of the CLDN1-EPHB6-ERK1/2-SLUG axis, which repressed metastasis, drug resistance, and cancer stemness, indicating that CLDN1 acts as a metastasis suppressor. CLDN1 upregulated the cellular level of EPHB6 and enhanced its activation, resulting in suppression of ERK1/2 signaling. Interestingly, DNA hypermethylation of the CLDN1 promoter abrogated SLUG-mediated suppression of CLDN1 in low-metastatic cancer cells. In contrast, the histone deacetylase inhibitor trichostatin A or vorinostat facilitated CLDN1 expression in high-metastatic cancer cells and thus increased the efficacy of chemotherapy. Combined treatment with cisplatin and trichostatin A or vorinostat had a synergistic effect on cancer-cell death. Conclusions: This study revealed that DNA methylation maintains CLDN1 expression and then represses lung cancer progression via the CLDN1-EPHB6-ERK1/2-SLUG axis. Because CLDN1 enhances the efficacy of chemotherapy, CLDN1 is not only a prognostic marker but a predictive marker for lung adenocarcinoma patients who are good candidates for chemotherapy. Forced CLDN1 expression in low CLDN1-expressing lung adenocarcinoma will increase the chemotherapy response, providing a novel therapeutic strategy.

An all-optical photonic-crystal-based encoder is proposed. The device is composed of two ring resonator waveguides with three input-port waveguides and two output-port waveguides in triangular-lattice photonic crystals. Transmission behaviors of the proposed device are verified by two-dimensional finite difference time domain method. The encoder can operate at various wavelengths such as 1.31, 1.49 and 1.55 μm, considering definitions of logic 0 and 1 being the normalized transmission as less than 5% and greater than 80%, respectively.

In this study, a novel low impact ionization rate (low-IIR) poly-Si thin film transistor featuring a current and electric field split (CES) structure with bottom field plate (BFP) and partial thicker channel raised source/drain (RSD) designs is proposed and demonstrated. The bottom field plate design can allure the electron and alter the electron current path to evade the high electric field area and therefore reduce the device IIR and suppress the kink effect. A two-dimensional device simulator was applied to describe and compare the current path, electric field magnitude distributions, and IIR of the proposed structure and conventional devices. In addition, the advantages of a partial thicker channel RSD design are present, and the leakage current of CES-thin-film transistor (TFT) can be reduced and the ON/OFF current ratio be improved, owing to a smaller drain electric field.

Treatment of ovarian cancer (OvCa) remains challenging owing to its high recurrence rates. Detachment of cancer cells into the peritoneal fluid plays a key role in OvCa relapse, but how this occurs remains incompletely understood. Here we examined global miRNA expression profiles of paired primary/recurrent OvCa specimens and identified a novel biomarker, microRNA-150-5p (miR-150-5p), that was significantly upregulated in 16 recurrent OvCa tissues compared with their matched primary specimens. Analyses of cohorts from two other groups confirmed that expression of miR-150-5p was associated with early relapse and poor survival of OvCa patients. Inhibition of miR-150-5p significantly inhibited the migration and invasion of OvCa cells and induced a mesenchymal-epithelial transition (MET) phenotype. We demonstrated that the proto-oncogene, MYB, is an miR-150-5p target in OvCa cells and that the miR-150-5p/c-Myb/Slug axis plays important roles in regulating epithelial-mesenchymal transition (EMT) in OvCa cells. Expression of MYB was significantly correlated with good clinical outcome in OvCa and was negatively correlated with Slug expression in late-stage clinical specimens. These results suggest that miR-150-5p upregulation mediates the progression of recurrent OvCa by targeting the c-Myb/Slug pathway. Inhibition of miR-150-5p may serve as a new therapeutic strategy for preventing recurrence of OvCa.

A current improved and electric field reduced double-gate (DG) polycrystalline silicon thin-film transistor with two-step source/drain (DGTSD-TFT) design is proposed and demonstrated in this study. The two-step source/drain (TSD) design, which consists of a raised source/drain (RSD) area together with a partial gate overlapped lightly doped drain (P-GOLDD) structure, can lower the device drain electric field (DEF) to reveal a better device performance. Comparisons have been made with respect to a traditional single top gate (STG) device. The operation current of the proposed DGTSD-TFT is almost twice as large as that of the STG structure. The OFF-state leakage current and kink effect, as well as the ON/OFF current ratio for this double-gate and two-step source/drain structure, are also improved simultaneously because of a reduced DEF. A hot carrier stress test reveals that that two-step source/drain structure can achieve more stable device characteristics than the traditional device.

We numerically investigated the surface plasmon resonance effects on photocatalytic activities using silver nanobeads photodeposited onto a titanium dioxide (TiO 2 ) layer by three-dimensional finite element method. Results show that the proposed case C structure exhibits significantly high photocatalytic activity in a wide range of incident angle of light and broad wavelength range in near-UV, visible and near-infrared. The enhanced electric field region, intensity and peak resonance wavelength could be increased by enhancing the inner medium dielectric constant ( e ) in silver nanobeads with e in the range 1.7689–11.56 and the incident angle of light θ in the range 30°–75°.

The gap enhancement and transmittance spectra properties of a periodic outline bowtie nanoantenna array (POBNA) which is embedded in a substrate with different depths are numerically investigated by using the finite element method. The surface plasmon resonance (SPR) modes obtained from the embedding cases are quite different from that of the free standing case. Near-field interactions across the bowtie-gaps and POBNA hollows at the localized SPR wavelengths resulted in an increase of magnitude in local field intensity and a redshift of transmittance resonance dip wavelength. The POBNA embedded in a silica substrate can be used as critical elements for nanoscale optical devices.

Coupling of incident light through an air region into an S-shape silver (Ag) plasmonic nanowire waveguide (SSAPNW) is a highly difficult challenge of light guiding on the surface of metal nanowire. In this paper, we numerically analyze the coupling effect of an SSAPNW which is covered by a dielectric medium using a finite element method. The coupling effect can be modulated by adjusting the Ag nanowire diameter and the covering dielectric medium width and wavelength of incident light, and the propagation length of surface plasmon (SP) coupling can be maximized. Simulation results reveal that the field confinement can be significantly improved and the majority of the electric field can be carried on the surface of a bending Ag nanowire. The effect of electric field transport along an SSAPNW due to SP coupling and Fabry-Perot resonance is investigated for different dimensions and lengths. Accordingly, long propagation lengths of about 41.5 μm for 10 × SSAPNW at an incident wavelength of 810 nm and longer propagation length can be achieved if more sections of an SSAPNW are used. Simulation results offer an efficient method for optimizing SP coupling into bending metal nanowire waveguides and promote the realization of highly integrated plasmonic devices.

We propose an all-optical AND gate based on a two-dimensional photonic crystal. The device is composed of a ring resonator waveguide with two input-port waveguides and one output-port waveguide in triangular-lattice photonic crystals. Transmission behaviors of the proposed device are investigated by the finite difference time domain method. The logic AND gate can operate at various wavelengths such as 1.30, 1.43, 1.45, 1.49, 1.51, and 1.55 μm, considering the definitions of logic 0 and 1 being less than 35% and more than 95%, respectively.

α-Catulin is an oncoprotein that helps sustain proliferation by preventing cellular senescence. Here, we report that α-catulin also drives malignant invasion and metastasis. α-Catulin was upregulated in highly invasive non–small cell lung cancer (NSCLC) cell lines, where its ectopic expression or short-hairpin RNA–mediated attenuation enhanced or limited invasion or metastasis, respectively. α-Catulin interacted with integrin-linked kinase (ILK), a serine/threonine protein kinase implicated in cancer cell proliferation, antiapoptosis, invasion, and angiogenesis. Attenuation of ILK or α-catulin reciprocally blocked cell migration and invasion induced by the other protein. Mechanistic investigations revealed that α-catulin activated Akt-NF-κB signaling downstream of ILK, which in turn led to increased expression of fibronectin and integrin αvβ3. Pharmacologic or antibody-mediated blockade of NF-κB or αvβ3 was sufficient to inhibit α-catulin–induced cell migration and invasion. Clinically, high levels of expression of α-catulin and ILK were associated with poor overall survival in patients with NSCLC. Taken together, our study shows that α-catulin plays a critical role in cancer metastasis by activating the ILK-mediated Akt-NF-κB-αvβ3 signaling axis. Cancer Res; 73(1); 428–38. ©2012 AACR.

Conventional heterostructure field-effect transistors (HFETs) have a high gate leakage current due to the gate electrode being in contact with the exposed channel layer and with the carrier-providing layer on the mesa sidewall. In this study, we use a new step-free (SF) air-bridge gate structure to reduce the gate leakage and improve the breakdown voltage. The proposed structure does not increase any MASKs as compared with the conventional process. In addition, this new structure promises a gate-source capacitance smaller than those of conventional heterostructure FET devices. Consequently, the high-frequency performance of the HFETs using the proposed structure can be improved.

In this paper, a high-performance single-gate double-channel polycrystalline-silicon thin-film transistor (DCTFT) is proposed and experimentally demonstrated for the first time. Two thin channels, accompanied with a raised source/drain (S/D) area, an offset structure, a drain field plate, and a field-induced drain region, are used in this device, allowing a lower S/D resistance and a better device performance. Our experimental results show that the on-current of the DCTFT is higher than that of the conventional structure, and the leakage current is greatly reduced simultaneously. In addition, the device stability, such as threshold voltage shift and drain on-current degradation under a high gate bias, is also improved by the design of two channels and the reduced drain electric field structures. The lower drain electric field of the DCTFT is also beneficial to scaling down the device for a better performance.

In the partially depleted (PD) SOI NMOSFET device, the floating body effect emerges due to the accumulation of excess holes in the neutral substrate region. The floating body effect will cause the current curve of kink effect in the saturation region. In this paper, we have discussed the kink effect in different situations and the branchcut method was used to separate the current component into two parts: (1) the parasitic BJT current, (2) the channel current, respectively. Then we find three different cases to analyze: (1) the body effect, (2) the parasitic BJT effect, (3) the combination effect. Furthermore, the partially covered oxide structure is used to suppress the parasitic BJT current without influencing the body effect. It can be proved that the kink effect has two different stages, the first kink effect and the second kink effect, respectively.

An analytical model is presented to determine the potential and electric field distribution along the semiconductor surface of new silicon-on-insulator (SOI) reduced surface field (RESURF) device. The SOI structure is characterized by a semi-insulating polycrystalline silicon (SIPOS) layer inserted between a silicon layer and a buried oxide. An improvement in the breakdown voltage due to the presence of the SIPOS shielding layer is demonstrated. Numerical simulations using medici are shown to support the analytical model.

The Kronig‐Penney model consists of a periodic potential function, which is used to derive the concepts of allowed and forbidden energy bands. Here, to circumvent the tedious evolution, it is helpful to use computer methods to derive the textbook equation of the analytic Kronig‐Penney model. The hierarchical methodology with the shorter symbols can effectively reduce the complication in the expression of the 4 × 4 matrix. By defining the symbol sequence, we can easily reduce terms by cancellation. With these methods and computer‐aided evolution, we can derive the Kronig‐Penney model from the matrix expression to the textbook form without the extremely laborious evolution.

Semiconductor device simulations sometimes have to solve for large‐scale and small‐scale variables at the same time, especially with density‐gradient models and hydrodynamic models. The usual way is to use the scaling factors, but scaled variables are still not of the same order of magnitude. We propose a log‐scale method to make all variables of similar orders without scaling factors. All variables in similar orders of magnitude will help Newton‐Raphson iterations to easily converge in device simulations. We use the divergence theorem of Gauss to discretize Poisson's and continuity equations, using the element‐by‐element method and develop an equivalent circuit model. The electron and hole concentrations are presented for a diode and an MOS capacitor by using the log‐scale method and the equivalent circuit model. The numerical results show the great capability of the equivalent circuit model with log‐scale method.

The Kronig–Penney model is quite useful for illustrating many important features of the quantum behaviour of electrons in periodic lattice. Although the Kronig–Penney model is well-known and has been discussed in solid state textbooks, we try to use a simple and accessible way without the extremely laborious and tedious algebra evaluation to solve Kronig–Penney model. This paper presents a simple method without solving the difficult eigen-problem to solve the Kronig–Penney model, and the important energy band characteristics can be easily obtained with circuit concepts. The simulation results are presented to demonstrate the accuracy and superiority of the model. Copyright © 2006 John Wiley & Sons, Ltd.

In this paper, we develop a three-dimensional (3-D) device simulator, which combines a simplified, decoupled Gummel-like method equivalent-circuit model (DM) with levelized incomplete LU (L-ILU) factorization. These complementary techniques are successfully combined to yield an efficient and robust method for semiconductor-device simulation. The memory requirements are reduced significantly compared to the conventionally used Newton-like method. Furthermore, the complex voltage-controlled current source (VCCS) is simplified as a nonlinear resistor. Hence, the programming and debugging for the nonlinear resistor model is much easier than that for the VCCS model. Further, we create a connection-table to arrange the scattered non-zero fill-ins in sparse matrix to increase the efficiency of L-ILU factorization. Low memory requirements may pave the way for the widespread application in 3-D semiconductor-device simulation. We use the body-tied silicon-on-insulator MOSFET structure to illustrate the capability and the efficiency of the 3-D DM equivalent-circuit model with L-ILU factorization. Copyright © 2007 John Wiley & Sons, Ltd.

Mergers and Acquisitions (M&A) play a significant role in technological strategic deployment. This case study describes a methodology applying two-stage grey decision-making to help businesses recognize the role of technology in creation of wealth to acquire opportunities for technology push. The study results show that the application can effectively assist corporations in controlling selection of technological assets and tailor a technological asset investment mode for them.

The fixed oxide charge will cause the MOS capacitor (MOS-C) flat-band voltage to shift. We can observe the potential distribution to determine the MOS-C flat-band voltage. However, the potential distribution can be obtained from the integration of the electric field distribution. The integration of the electric field distribution is classified into the vertical and horizontal integrations. In this paper, we use the equivalent-circuit model to demonstrate the flat-band voltage of the non-ideal MOS-C. The equivalent-circuit model of Poisson's equation includes two fixed charges Q′f1 and Q′f2 in the oxide layer region. Because the horizontal integration method is the superposition method, the equivalent-circuit model for the horizontal integration is divided into 3 types. Hence, the flat-band voltage for the horizontal integration is equal to the sum of the VG1, VG2, and VG3 for the flat-band condition. By comparison, the simulation results of the horizontal integration method approximate to the vertical integration method. Copyright © 2006 John Wiley & Sons, Ltd.

In this paper, a simplified method for solving the Schrodinger–Poisson equation set in a quantum mechanical (QM) simulation is presented. This method simplifies the conventional Schrodinger and Poisson equations and then converts the simplification equation into an equivalent circuit form. During the QM simulation, the equivalent circuit model can replace the Schrodinger and Poisson's equations. In the equivalent circuit, the node voltages are taken as wave functions, and the electron concentration in the MOS inversion layer can be easily presented by solving the Schrodinger–Poisson equivalent circuit model. The simulation results are presented to demonstrate the quantum effects in the MOS inversion layer. Copyright © 2006 John Wiley & Sons, Ltd.

Numerical simulation of semiconductor devices plays a very important role in the design and development of integrated circuits. We have successfully proposed a new level of convergence performance, when truncation parameter α =1, by combining a simplified, decoupled Gummel-like method (DM) equivalent-circuit model and levelized incomplete LU (L-ILU) factorization in simulating arbitrary, planar semiconductor devices. Further, in order to overcome the problem of decoupled method that the boundary of the device's terminal must be connected to a voltage source, we present a partial decoupled equivalent-circuit model (PDM) with levelized incomplete LU factorization. The complementary techniques for enhancing matrix diagonal dominance and helping program convergence are successfully combined to yield an efficient and robust decoupled nonlinear solution method for numerical simulation. It not only saves memory consumption but also can provide an effective matrix solver for mixed-level semiconductor device and circuit simulation.

In this paper, we study on a 1D BJT model, which saves the memory size and computation time and verify that the characteristic of 1D BJT model is in good agreement with 2D BJT model. We use the equivalent circuit approach to simulate the BJT device. Poisson's equation and continuity equations for electron and hole are formulated into a subcircuit format suitable for general circuit simulator in the equivalent circuit approach. In order to solve the 2D device simulation, the simulation environment needs a powerful solver. So we use the band matrix solver to replace the full matrix solver. But the 2D BJT simulation still needs a large computation time, so we must develop the efficient 1D BJT model. In 1D BJT simulation, we have overcome the base boundary condition and verified that the base boundary conditions in 1D BJT model closely approach to that in 2D BJT model. Finally, we apply it to two applications and study the operation concepts of these applications. Copyright © 2002 John Wiley & Sons, Ltd.

In this letter, a high-current self-aligned raised source/drain polycrystalline silicon thin-film transistor (HCSARSD-TFT) is proposed and demonstrated for the first time. This new self-aligned device features two channels, i.e., a nitride spacer offset-gated structure and a raised source/drain (RSD) region, that reveal better device performance. Our experimental results show that the on-current of the HCSARSD-TFT is about two times higher than that of the conventional structure, and the leakage current is considerably reduced simultaneously. In addition, since the gate and RSD areas of the proposed device are self-aligned, no extra mask is needed when comparing it with conventional coplanar RSD TFTs.

Numerical simulation of semiconductor devices plays a very important role in the design and development of integrated circuits. We will present a new circuit simulator with an improved Levelized Incomplete LU method to perform such simulations. To have an environment for evaluating the interaction between a semiconductor device and a circuit, we use the equivalent circuit approach. This approach allows for simple representation carrier transport models of devices through equivalent circuit elements such as voltage controlled current sources and capacitors. Therefore, we can perform mixed‐level simulation in general circuit simulators. We will take a PN diode switching circuit and MOSFET as examples to test our equivalent circuit model and the improved circuit simulator. The comparison between improved matrix solution method and the conventional method will be demonstrated too. We will also show our method yields better matrix solutions than conventional methods

In circuit simulation, the CPU time is spent in two parts: one is to transfer the circuit equation into the corresponding linear equation Ax = B , the other is to solve this matrix equation. In order to improve the simulation speed and apply our method to mixed-level device and circuit simulation, we propose to simplify the creation of the matrix equation by equivalent subcircuit, and speed up the simulation by levelized incomplete LU factorization [Karl-Michael E, Walter LE. IEEE Trans Comp Aided Des Integ Circ and Sys 1995;14:720.]. The levelized incomplete LU is used to solve Ax = B because it offers, the good convergence of the direct method and the high speed, small memory space of the iteration method. The Ax = B is obtained by transferring the Poisson equation and continuity equation into their equivalent circuits [Leblebici Y, Unlu MS, Morkoc H, Kang SM. IEEE Int Symp Circ and Sys 1992;2:895; 1995;13:396.] to simplify the mixed-level simulation. Finally, we will apply the above methods to the simulation of PN diodes and verify their performance on the simulation and design of semiconductor devices.

In this letter, a novel double-channel polycrystalline-silicon (poly-Si) thin-film transistor (DCTFT) is proposed and demonstrated. The DCTFT, which includes two channels with a thicker source/drain (S/D) region, a field-induced drain, and an offset structure, reveals better device performance and lower S/D resistance. Our experimental results show that the on-current of the DCTFT is higher than that of the conventional structure, and the leakage current is greatly reduced simultaneously. In addition, the device stability such as the threshold-voltage shift under a high gate bias is also improved by this two-channel and thick-S/D-region structure design. The lower drain electric field of the DCTFT is also a benefit to the device scaling down for better performances.

This paper presents an adapted Gummel method (AGM) used in the two-dimensional device simulation of an amorphous-silicon (a-Si) thin-film transistor (TFT). Firstly, the AGM for amorphous silicon is developed by modifying the Gummel method (GM) for crystalline silicon. Secondly, the AGM is implemented into a two-dimensional device simulator for the simulation of a-Si TFTs. The simulation results show that the AGM converges well while the GM fails to converge for the simulation of a-Si TFTs. Hence, the AGM is a useful technique for the simulation and analysis of a-Si TFTs. © 1997 by John Wiley & Sons, Ltd.

This paper uses the C++ to develop an adapted band matrix solver to simulate the i-v curve and the drain current of the 2-D double-gate n-channel MOSFET, including different doping concentrations which from 5×10 (cm-3) to 5×10 (cm-3) and channel thickness which from 5 nm to 15 nm. And it discusses the threshold voltage from the i-vg curve and selects the more appropriate doping concentration and channel thickness to complete the following experiments. And then it simulates if-vg curve to determine threshold voltage which can present the channel on-off situation and calculates drain current which is in different gate voltage. It also can simulate the electric potential of the x-axis and y-axis. In the figure of the electric potential we can obtain the depletion width. It also analyzes the subthreshold, the linear and the saturation region in i-v curve, and we can find out the values of sub-threshold swing in the subthreshold region of the i-v curve and the value of the drain current in the saturation region of the i-v curve. It compares the results with the other reference papers. Finally, the equations of the threshold voltage can be developed, and we calculate the threshold voltage of double-gate n-channel MOSFET. The result obtained by the equation of the threshold voltage will be compared with result by 2-D simulation. The depletion width can be obtained as an analytical equation. The analytical depletion width can be verified by the figure of the x-axis and y-axis electric potential from 2-D simulation. The 2-D simulation also verifies the result with the drain current equation which is obtained by Pois-son's equation. For circuit application, an inverter including a double-gate n-channel MOSFET and a 100kΩ resistor will be used to simulate the vo-vi characteristics and analyzes the parameters of the inverter (e.g. VOh, VOl, Vih, Vil, VS), and the noise margin (e.g. NML, NMH) will be calculated in order to determine the inverter's performance and quality.

Prostate cancer (PCa) is a leading cause of mortality and morbidity in men worldwide, and emerging evidence suggests that the CD44(high) prostate tumor-initiating cells (TICs) are associated with its poor prognosis. Although microRNAs are frequently dysregulated in human cancers, the influence of microRNAs on PCa malignancy and whether targeting TIC-associated microRNAs inhibit PCa progression remain unclear. In this study, we found that miR-320 is significantly downregulated in PCa. Overexpression of miR-320 in PCa cells decreases PCa tumorigenesis in vitro and in vivo. Global gene expression profiling of miR-320-overexpressing PCa cells reveals that downstream target genes of Wnt/β-catenin pathway and cancer stem cell markers are significantly decreased. MicroRNA-320 inhibits β-catenin expression by targeting the 3'-untranslated region of β-catenin mRNA. The reduction of miR-320 associated with increased β-catenin was also found in CD44(high) subpopulation of prostate cancer cells and clinical PCa specimens. Interestingly, knockdown of miR-320 significantly increases the cancer stem-like properties, such as tumorsphere formation, chemoresistance and tumorigenic abilities, although enriching the population of stem-like TICs among PCa cells. Furthermore, increased miR-320 expression in prostate stem-like TICs significantly suppresses stem cell-like properties of PCa cells. These results support that miR-320 is a key negative regulator in prostate TICs, and suggest developing miR-320 as a novel therapeutic agent may offer benefits for PCa treatment.

We proposed a binary numbers operating NOT/NOR gates with cylindrical silicon structure in all-optical logic system. Operating principle, as revealed by both theoretical calculation and two dimensional finite-difference time-domain simulation. Proposed logic system can show their capabilities. This device is potentially applicable for photonic integrated circuits.

We propose a AND logic gate based on photonic crystal with cylindrical silicon structure. It takes advantages of the device sizes are drastically reduced to a scale of a few tens of micrometers and the easy-to-implement logic function. Furthermore, the multi-input AND gate can apply to all-optical Arithmetic Logic Unit (ALU) devices of photon computer in the future.

Cellular senescence functions as a tumor suppressor that protects against cancer progression. α-Catulin, an α-catenin-related protein, is reported to have tumorigenic potential because it regulates the nuclear factor-κB (NF-κB) pathway, but little is known about its clinical relevance and the mechanism through which it regulates cancer progression. Here, we found that α-catulin mRNA levels were significantly upregulated in cancer cell lines and clinical oral squamous cell carcinomas, which positively correlated with tumor size (P=0.001) and American Joint Committee on Cancer (AJCC) stage (P=0.004). α-Catulin knockdown in the OC2 and A549 cancer cell lines dramatically decreased cell proliferation and contributed to cellular senescence, and inhibited OC2 xenograft growth. Mechanistic dissection showed that α-catulin depletion strongly induced the DNA-damage response (DDR) in both cell lines, via a p53/p21-dependent pathway in A549 cells, but a p53/p21-independent pathway in OC2 cells carrying mutant p53. Global gene expression analysis revealed that α-catulin knockdown altered cell-cycle regulation and DDR pathways at the presenescent stage as well as significantly downregulate several crucial genes related to mitotic chromosome condensation, DDR and DNA repair systems, which suggests that its depletion-induced cellular senescence might be caused by chromosome condensation failures, severe DNA damage and impaired DNA repair ability. Our study provides evidence that α-catulin promotes tumor growth by preventing cellular senescence and suggests that downregulating α-catulin may be a promising therapeutic approach for cancer treatment.

For stimulates great developments in high-speed and high-capacity Cloud Computing Technologies (CCT) systems in the future. The all-optical logic gate based on planar photonic crystal (PPC) waveguide is a promising technology. We design an all-optical AND gate in PPC, as an ultracompact component for planar lightwave circuit integration with suitable choice of parameters, perform this task. The PPC waveguides are composed of circular dielectric rods set in two-dimensional triangular lattice. To realize the AND logic function, as predicted using 2D finite-difference time-domain simulations. The combination of the ring and line defect coupler waveguides forms the device. On the basis of our simulations, we found that the optimized scheme maximizes the power transmission above 80% at a wavelength of 1.55 um. Besides, this device can apply to all-optical Arithmetic Logic Unit (ALU) in all-optical computing and potentially applicable for photonic integrated circuits (PICs) in the future.

Termination region plays an important role in high voltage power VDMOSFETs. Termination structure such as floating-field-limiting-rings and field plates are the common structures used in a termination region because they can be fabricated without additional masks. However, sometimes we use both of them, sometimes only the floating-field-limiting-ring. The difference between these structures must be known while designing. In this paper, we compare and discuss the difference of the floating-field-limiting-rings with and without field plates. Understanding the difference is helpful for designing and saving time.

A high voltage power vertical double-diffused MOSFET with reduced JFET area by using an overall implantation was discussed. The reduced JFET area realizes a low gate charge and a high switching speed, due to the reduction of the gate-drain overlapped area. The measured gate-drain charge and gate charge can be improved by 61.1% and 71.8 %, respectively. The F.O.M of the proposed device and the conventional one is 64.4 nΩ×C and 190.9 nΩ×C, respectively. We also discussed the reliability issue and compared the avalanche capability to the proposed structure and the conventional device. The ruggedness of the proposed devices can be improved by a higher cell density design with a planar oxide self align p+ implantation process.

Several studies indicated that stress would induce analgesia. Noise, one of the stressors, was assumed to be one of the elements to enhance the threshold of pain tolerance. Since noise might affect human's daily life, it is important to know the mechanism underlying this phenomenon. The objective of this study was to explore the possible mechanism which was trying to explain how the noise affects central nervous system and the possible relationship between this effect and the involvement of opioid neurons. In the preliminary study, the analgesic effect was corroborated in ICR mice in a formalin study. The results are as follows: [1] Naloxone (a micro-opioid receptor antagonist; 1 mg/kg, i.p.), beta-FNA (a delta-opioid receptor antagonist; 5, 10 mg, i.c.v.) and naltrindole (a delta-opioid receptor antagonist; 1, 5 mg/kg, i.p.) were found to reduce antinociceptive effect. [2] nor-BNI (a kappa-antagonist; 1 microg, i.c.v.) had much effect on noise induced analgesic. In conclusion, this study suggests that noise stress enhanced the threshold of analgesia, which might be related to micro- and delta-opioid receptors in the central nervous system.

Potential and strength of surface electric field distribution have strongly influence on breakdown voltage and reliability of power semiconductor devices. Potential distribution can be determined by different field-limiting ring and field plate design which can be described by solving Poisson's equation in one dimension briefly. In this paper, the influence of design factors such as spacing between main junction and ring, ring width, and field plate width on potential and strength of surface electric field distribution are analyzed. From the simulation results, the relationship between those factors and potential and strength of surface electric field distribution can be found. Understanding the effect of design factors upon the junction termination edge, multi field-limiting rings and field plates of high breakdown power devices can be designed.