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Background/aim: This study performed typing of chronic obstructive pulmonary disease (COPD) using high-resolution computedtomography (HRCT) to determine the association with smoking, matrix metalloproteinases, and common comorbidities.Materials and methods: The study enrolled 94 hospitalized patients. Participants were divided into a group of 69 current and formersmokers (group A) and a group of 25 that had never smoked (group B). Patients were also divided into 3 categories according to thedegree of emphysema and bronchial wall thickness using HRCT to determine the association with levels of matrix metalloproteinase 9(MMP-9) and TIMP-1, as well as associated comorbidities. These three categories were: type A - no or mild emphysema, with or withoutbronchial wall thickening; type E - emphysema without bronchial wall thickening; and type M - both emphysema and bronchial wallthickening.Results: The low attenuation area (LAA) scores in group A patients were higher than those in group B (t = 2.86, P < 0.01); correlationanalysis showed that smoking was associated with a decline of the forced expiratory volume in 1 s and forced vital capacity ratio (FEV1/FVC%) and higher LAA scores in patients with COPD (F = 4.46, F = 8.20, P < 0.05). The levels of MMP-9 in group A were higherthan those in group B (t = 3.65, P < 0.01). Among COPD patients with more than 3 comorbidities, there were statistically significantdifferences in both the smoking group and the nonsmoking group (chi-square = 12.08, P < 0.01). When compared to type A patients,who had coincident cardiovascular diseases in the smoking group, patients of type M and E showed statistically significant differences(F = 2.42 and 2.12, P < 0.05).Conclusion: Emphysema was more severe in smokers. Metalloproteinase levels in smokers were higher than those in nonsmokers.Moreover, comorbidities were more severe in smokers.

RNA interference (RNAi) functions as a potent antiviral immunity in plants and invertebrates; however, whether RNAi plays antiviral roles in mammals remains unclear. Here, using human enterovirus 71 (HEV71) as a model, we showed HEV71 3A protein as an authentic viral suppressor of RNAi during viral infection. When the 3A-mediated RNAi suppression was impaired, the mutant HEV71 readily triggered the production of abundant HEV71-derived small RNAs with canonical siRNA properties in cells and mice. These virus-derived siRNAs were produced from viral dsRNA replicative intermediates in a Dicer-dependent manner and loaded into AGO, and they were fully active in degrading cognate viral RNAs. Recombinant HEV71 deficient in 3A-mediated RNAi suppression was significantly restricted in human somatic cells and mice, whereas Dicer deficiency rescued HEV71 infection independently of type I interferon response. Thus, RNAi can function as an antiviral immunity, which is induced and suppressed by a human virus, in mammals.

Background MicroRNAs (miRNAs) are short, noncoding RNAs that inhibit the expression of target genes that play roles in tumorigenesis. MiR-21, miR-31, and miR-184 are oncogenic miRNAs for head and neck squamous cell carcinoma (HNSCC). Factor-inhibiting hypoxia (FIH)-inducible factor is known to inactivate hypoxia-induced downstream effectors and is involved in HNSCC suppression. This study investigates whether miR-21, miR-31, and miR-184 target FIH in HNSCC. Methods Reporter assays, Western blot analysis, quantitative reverse transcriptase-polymerase chain reaction (PCR) analysis, and phenotypic assays were used to prove that miR-21, miR-31, and miR-184 directly target FIH. Clinicopathological implications of the gene expression were also analyzed. Results MiR-21, miR-31, and miR-184 directly bind to various sites in the 3′ untranslated region (UTR) of FIH transcript, and this binding is associated with decreased FIH protein expression in HNSCC cells. Treatment with the precursors of these miRNAs increases the proliferation and migration of HNSCC cells. Concomitant treatment with precursors repressed FIH and enhanced oncogenicity most profoundly. Upregulation of miR-21, miR-31, and miR-184 expression is found in more than 80% of HNSCC tumors and 72% of tumors have concordant upregulation of these 3 oncogenic miRNAs. The highest expression of these miRNAs is present in T4b and stage IVB tumors. Downregulation of FIH mRNA expression is noted in 69% of HNSCC tumors, and in tumors exhibiting high expression of these miRNAs, the FIH mRNA expression is consistently downregulated. Conclusion This study provides novel clues indicating that miR-21, miR-31, and miR-184 co-target FIH tumor suppressor during pathogenesis in the vast majority of HNSCC. © 2014 Wiley Periodicals, Inc. Head Neck, 2015

This paper reviews the physical mechanisms and compact modeling approaches of two physical damages in MOS devices induced by electrostatic discharge (ESD) stresses; namely gate oxide breakdown and thermal failures. Theories underlying the failure mechanism are discussed and compact models that can be used to monitor ESD induced gate oxide breakdown and thermal failure are developed. Related work reported in the literature is discussed, and benchmarking of measurement data versus simulation results are included in support of the modeling work.

The first thiocarboxylation of styrenes and acrylates with CO

The transition-metal-free lactonization of heteroaryl and alkenyl C-H bonds with carbon dioxide is reported to synthesize important coumarin derivatives in moderate to excellent yields. These redox-neutral reactions feature a broad substrate scope, good functional group tolerance, facile scalability, and easy product derivatization.

This chapter presents the design of CMOS UWB tunable sub-nanosecond impulse and monocycle-pulse BPSK transmitters. The UWB impulse transmitter produces positive and negative tunable impulse signals corresponding to the high- and low-level modulation signals, respectively. The positive and negative impulse signals have amplitudes of 0.8 and 0.6 V with tunable pulse widths from 100 to 300 ps, respectively. The UWB monocycle-pulse transmitter produces monocycle pulse signals of opposite polarities having peak-to-peak amplitudes of about 0.6–0.8 V and tunable pulse widths between 100 and 300 ps. This chapter also covers the design of the CMOS impulse generator and BPSK modulator used in the UWB impulse and monocycle-pulse transmitters. The impulse generator can generate 0.95–1.05 V peak-to-peak Gaussian-type impulse signal with 100–300 ps tunable pulse duration. Moreover, this chapter includes the design of a CMOS monocycle pulse generator, which can produce 0.7–0.75 V peak-to-peak monocycle pulse with 140–350-ps tunable pulse duration.

This chapter covers the design and performance of a low-cost, compact UWB uniplanar antenna operating across the entire UWB of 3.1–10.6 GHz, which can be easily integrated with the designed CMOS UWB transmitter and receiver. Especially, various impulse time-domain measurements are conducted to demonstrate the performance and suitability of the designed UWB uniplanar antenna for transmitting and receiving impulse signals that contain all frequency components from 3.1 to 10.6 GHz, which are essential for UWB impulse systems. The UWB uniplanar antenna is further integrated with the previously developed CMOS tunable pulse generator to form the UWB transmit prototype. This UWB transmit prototype can transmit monocycle pulses with pulse duration tunable from 160–350 ps with the impulses supplied from the integrated pulse generator. The received pulses maintain good symmetry with no serious distortion and ringing. The UWB transmit prototype can also transmit signals having shape similar to the first derivative of the monocycle pulses provided by the integrated pulse generator. Both the impulse and monocycle-pulse transmission results clearly demonstrate the workability of the CMOS-based tunable UWB transmit prototype for UWB impulse systems.

This chapter covers the fundamentals of UWB impulse systems operating across or within the unlicensed UWB frequency band of 3.1–10.6 GHz. It provides the essence of UWB impulse systems including the spectrum mask, advantages and applications of UWB impulse systems, UWB impulse signals including Gaussian impulse, doublet pulse and monocycle pulse, modulations including PPM, PAM, OOK and BPSK, UWB impulse transmitters and receivers, and UWB antennas.

This paper considers lending to finance projects in a setting where repayment enforcement appears impossible. The loan was illegal and thus legally unenforceable. Creditors were incapable of applying private coercion to force repayment. Borrowers lacked both collateral and reputation capital. Project cash flows were unobservable. The projects were the acquisition of Imperial administrative posts by scholars in nineteenth century Qing China. The lending mechanism was the “trusted-assistant loan.” Our model of trusted-assistant lending shows that it is a renegotiation-proof implementation of efficient state dependent financing. Empirical analysis of officials’ diaries and bank records shows that the employment of trusted-assistant lending and the performance of trusted-assistant loans conforms roughly with the model’s predictions.

Defective rutile TiO2 (110) surfaces with one bridging-oxygen vacancy pair (OVP) and two next nearest neighbored bridging-oxygen vacancies belonging to the same row (NNN-OVs, i.e., two bridging-oxygen vacancies separated by a single oxygen atom) were studied using density functional theory (DFT) calculations. The results of a perfect surface and a defective surface with single bridging-oxygen vacancy (OV) were also shown. The reactivity of these surfaces was investigated by studying their interaction with a water molecule. Results show the NNN-OVs site is the most favorable site for water adsorption of two modes, molecular and dissociated adsorption, especially for dissociated adsorption. Upon dissociated adsorption on the NNN-OVs site, the whole system would release energy of 2.07 eV, much more than the energy released in any other site. It indicates the high reactivity of NNN-OVs as the best trap center. The 5-fold Ti sites show similar behaviors despite the existence of different defects. Adsorption on...

The interaction between methanol and the rutile TiO2 (1 1 0) surface with bridging oxygen-vacancy pairs (OVPs) defects is studied with DFT method. The OVP is the most stable site for adsorption of molecular methanol and dissociated fragments, but not the most active one for dissociation process since OVP exhibits slightly higher energy barrier than single bridging oxygen vacancy. In addition, the defect of OVP does not have significantly different influence on the adsorption structure and dissociation process of adsorbed methanol on 5-fold Ti atoms at diverse positions: close to the vacancy or a little further from the vacancy.

Electrostatic discharge (ESD) devices based on diodes and silicon controlled rectifier for RF I/O protection are evaluated on both ESD and RF performance. Varying from the architecture, layout design and metal interconnection, candidate devices show different parasitic capacitance, ESD efficiency, and turn on speed. Potential solution for further RF I/O application is verified.

Transient characteristics of vertical GaN diodes fabricated on bulk GaN substrates are investigated. When forward biasing the diodes using discrete pulses, the results yield quasi-static I-V curves with two different on-resistances and two turn-on stages. Transient waveforms measured at different voltages are then used to explain the observed behavior and underlying physics. A relatively large overshoot voltage is also observed at the very beginning of the transient voltage waveform, indicating that a relatively long time is required to transition the GaN diode from the high to low resistance state.

In this paper, characteristics of electrostatic discharge (ESD) protection devices operating under ESD stress and various ambient temperatures are investigated. The devices considered are a P +/NW diode and several silicon controlled rectifiers (SCRs) including Lateral SCR (LSCR), Modified Lateral SCR (MLSCR), No Snapback SCR (NS-SCR), Low Voltage Triggering SCR (LVTSCR), and P-Substrate Triggered SCR (PSTSCR) fabricated in a 0.35 μm BCD (Bipolar-CMOS-DMOS) technology. Measurements are conducted using the Barth 4002 transmission line pulse (TLP) tester and the Signatone S1060 heating module, and the TLP I–V characteristics are analyzed in details. TCAD simulation is carried out and underlying physical mechanisms related to the effect of temperature on key ESD parameters are provided.

Design trade-offs of a novel structure embedded with a silicon controlled rectifier and dual-diode (DD-SCR) for high speed I/O applications are presented. A metal-bounded DD-SCR exhibiting a high failure current (It2), small on-state resistance (Ron), low voltage overshoot and low parasitic capacitance is introduced as an optimal device for such applications in advanced CMOS processes. Comprehensive characterizations including capacitance and current vs. voltage measured using transmission line pulsing (TLP) and very-fast TLP (VFTLP) are undertaken to demonstrate the DD-SCR performance.

A novel power-clamp assisted complementary MOSFET (PCACMOS), modified from traditional gate-coupled complementary MOSFET (GCCMOS), is proposed for high robust ESD (Electrostatic discharge) protection application. The power-clamp achieves by RC-NMOS and designs by Spice simulation. The comprehensive performance of the protection schemes are evaluated by the figure of merit (FOM). Compared with traditional gate-coupled MOSFET (GCCMOS) protection scheme, the power-clamp assisted complementary MOSFET (PCACMOS) protection scheme has a similar turn-on speed but higher FOM.

A novel gate-suppression technique derived from source-pumping technique is proposed for Electrostatic Discharge (ESD) protection application. By employing the complementary SCR structure, an improved source-pumping and the gate-suppression scheme are able to extend ESD window and endure a high level of ESD impact without additional layout area cost. The fast rise time TLP test revealed the gate-suppression technique provide more effective protection than the source-pumping technique.

Experiments with ZnO Metal-Oxide-Semiconductor （MOS） under different circumstances were made to get four different I-V curves. There were four conditions: dark, and tests with the green, blue, ultraviolet LED light. According to references, three parameters B，VB0and Nbarrcould be acquired by fitting lines of the I-V curves using MATLAB and LabVIEW. From their definitions, B, VB0and Nbarrindicate photoelectric properties of ZnO cooperatively under concrete conditions. VB0,grain boundary potential, is parameter of extrinsic properties of ZnO determined by both ZnO and testing conditions. So VB0is critical to control the photoelectric properties of ZnO. A smaller VB0, the stronger the photoelectric response of ZnO and the lager the efficiency of photoelectric conversion. Besides, this theory can be expanded to test the photoelectric properties of the other semiconductor materials. And I-V curves can direct the application of these materials efficiently.

A novel Substrate-Engineered Gate-Grounded NMOS (GGNMOS) structure with very low trigger voltage is proposed to protect the ultra-thin gate oxide effectively in nanoscaled integrated circuits. This device is designed and verified in a 65 nm CMOS process. With increased substrate resistance and pumped triggering current provided by power bus controlled PMOS, this structure features a significantly reduced trigger voltage of 2.8 V and an enhanced uniform conduction of multi-fingers. The failure current can be improved by 23.5% compared with traditional GGNMOS.

J Oral Pathol Med (2011) 40: 560–566 Backgrounds: MicroRNAs are small noncoding RNAs involved in posttranscriptional gene regulation, which play an important role in both physiological functioning and pathological progression. The miR-221/miR-222 microRNA family has been shown to be related to the neoplastic process in a number of different types of cancers; nevertheless, its function in oral squamous cell carcinoma (OSCC) remained uncertain. Materials and Methods: Paired OSCC and matched noncancerous oral mucosa were examined for miR-221/miR-222 expression using quantitative reverse-transcription PCR. Ectopic expression of miR-221/miR-222 by lentiviral infection was investigated to explore its in vitro and in vivo impact on the oncogenic phenotype and the expression of various target genes. The expression of Cip/Kip cell cycle regulator p27 in tumors was analyzed with immunohistochemistry. Results: The expression levels of miR-221 and miR-222 were highly correlated in OSCC. Increased miR-221/miR-222 expression was found in 40% of OSCC tissues. The ectopic expression of miR-221 or of miR-222 increased growth and anchorage-independent colony formation of OSCC cell lines. It also resulted in an increase in the tumorigenesis of an OSCC cell line in nude mice. Western blot analysis suggested that p27 and p57 might be the targets of miR-221/miR-222. p27 expression was reversely associated with the miR-221 and miR-222 expression level in OSCC tissues. Conclusions: Our findings suggested that increased miR-221/miR-222 expression was associated with the OSCC cell growth.