Interface-state-induced degradation of GIDL current in n-MOSFETsunder hot-carrier stress

The dependence of increase in post-stress gate-induced-drain-leakage (GIDL) current in n-MOSFET's on creation of interface states (ΔDit) during hot-carrier stress with VG = 0.5 VD was investigated. An interface-trap-assisted tunneling conduction mechanism is proposed to account for the increase. The stress method of VG = 0.5 VD can generate a lot of interface traps near the valence band in thermal oxide samples, which is considerably suppressed in nitrided oxide samples. From the linear relationship between increase in post-stress GIDL current and created interface-state density during hot-carrier stress, ΔDit values can be estimated.published_or_final_versio

The political economy of private firms in China

The sweeping change in political economy associated with the spectacular growth of the private sector in China is not much studied in economics literature. This paper fills in this gap. The central subject of this paper is the political economy nature of the Chinese private sector and of the CPC. Empirically, we examine the dynamics of rent creation from the party membership and other political connections when the regime is changed from anti-capitalistic to pro-capitalistic. Endogeneity problems are addressed. We identify the causality of rents and private entrepreneurs’ political connections, and explore the implications of these political elites’ rents for social welfare in terms of productivity.postprin

Anatomical Changes and Predictors of Angle Widening After Laser Peripheral Iridotomy: The Zhongshan Angle Closure Prevention Trial

PURPOSE: To assess anatomical changes after laser peripheral iridotomy (LPI) and predictors of angle widening based on anterior segment OCT (AS-OCT) and angle opening based on gonioscopy in mainland Chinese primary angle closure suspects (PACS). DESIGN: Prospective observational study. PARTICIPANTS: 454 subjects aged 50 to 70 years with PACS. METHODS: Subjects received clinical examinations including gonioscopy and AS-OCT imaging at baseline and 2 weeks after LPI as part of the Zhongshan Angle Closure Prevention (ZAP) Trial. PACS was defined as inability to visualize pigmented trabecular meshwork in two or more quadrants on static gonioscopy. LPI was performed on one eye per subject in a superior (between 11 to 1 o'clock) or temporal or nasal (at or below 10:30 or 1:30 o'clock) location. Biometric parameters in horizontal and vertical AS-OCT scans were measured and averaged. Multivariable linear and logistic regression modeling were performed to determine predictors of angle widening, defined as change in continuous measurements of mean angle opening distance (AOD750), poor angle widening, defined as the lowest quintile of change in mean AOD750, and poor angle opening, defined as residual PACS after LPI based on gonioscopy. MAIN OUTCOME MEASURES: Anatomical changes and predictors of angle widening and opening after LPI. RESULTS: 454 subjects were included in the analysis. 219 received superior LPIs and 235 received temporal or nasal LPIs. There were significant changes among most biometric parameters (p<0.006) after LPI, including greater AOD750 (p<0.001). 120 eyes (26.4%) had residual PACS after LPI. In multivariable regression analysis, several baseline parameters, including superior LPI location (p=0.004), smaller AOD750 (p<0.001), and greater iris curvature (p<0.001), were predictive of greater angle widening. Temporal or nasal LPI locations (OR=2.60, p<0.0001) and greater baseline AOD750 (OR=2.58, 0.1 mm increment, p<0.001) were most predictive of poor angle widening based on AS-OCT. Smaller mean gonioscopy grade (OR=0.34, 1 grade increment) was most predictive of poor angle opening based on gonioscopy. CONCLUSIONS: Superior LPI location results in significantly greater angle widening based on AS-OCT compared to temporal or nasal locations in a Chinese population with PACS. This supports consideration of superior LPI locations to optimize anatomical changes after LPI

Ocular Biometric Risk Factors for Progression of Primary Angle Closure Disease: The Zhongshan Angle Closure Prevention Trial

PURPOSE: To assess baseline ocular biometric risk factors for progression from primary angle closure suspect (PACS) to primary angle closure (PAC) or acute angle closure (AAC). DESIGN: Prospective observational study. PARTICIPANTS: 643 mainland Chinese aged 50 to 70 years with untreated PACS. METHODS: Participants received baseline clinical examinations including gonioscopy, anterior segment OCT (AS-OCT) imaging (Visante OCT, Carl Zeiss Meditec, Dublin, CA), and A-scan ultrasound biometry as part of the Zhongshan Angle Closure Prevention (ZAP) Trial. PACS was defined as inability to visualize pigmented trabecular meshwork in two or more quadrants based on static gonioscopy. PAC was defined as development of elevated intraocular pressure (IOP) > 24 mmHg or peripheral anterior synechiae (PAS). Progression was defined as development of PAC or an acute angle closure (AAC) attack. Multivariable logistic regression models were developed to assess biometric risk factors for progression. MAIN OUTCOME MEASURES: Progression from PACS to PAC or AAC over 6 years. RESULTS: 643 untreated eyes (609 non-progressors, 34 progressors) of 643 ZAP participants were included in the primary analysis. In a multivariable model with continuous parameters, narrower horizontal angle opening distance 500 μm from the scleral spur (AOD500; OR=1.10 per 0.01 mm decrease, p=0.03), flatter horizontal iris curvature (IC; OR=1.96 per 0.1 mm decrease, p=0.01), and older age (OR=1.11 per year increase, p=0.01) at baseline were significantly associated with progression (AUC=0.73). Smaller cumulative gonioscopy score was not associated with progression (OR=1.03 per 1 modified Shaffer grade decrease; p=0.85) when replacing horizontal AOD500 in the multivariable model. In a separate multivariable model with categorical parameters, participants in the lowest quartile of horizontal AOD500 (OR=3.10, p=0.002) and IC (OR=2.48, p=0.014) measurements and aged 59 years and older (OR=2.68, p=0.01) at baseline had higher odds of progression (AUC=0.72). CONCLUSIONS: Ocular biometric measurements can help risk stratify patients with early angle closure for more severe disease. AS-OCT measurements of biometric parameters describing the angle and iris are predictive of progression from PACS to PAC or AAC, whereas gonioscopy grades are not

Electronic structures of free-standing nanowires made from indirect bandgap semiconductor gallium phosphide

We present a theoretical study of the electronic structures of freestanding nanowires made from gallium phosphide (GaP)--a III-V semiconductor with an indirect bulk bandgap. We consider [001]-oriented GaP nanowires with square and rectangular cross sections, and [111]-oriented GaP nanowires with hexagonal cross sections. Based on tight binding models, both the band structures and wave functions of the nanowires are calculated. For the [001]-oriented GaP nanowires, the bands show anti-crossing structures, while the bands of the [111]-oriented nanowires display crossing structures. Two minima are observed in the conduction bands, while the maximum of the valence bands is always at the $\Gamma$-point. Using double group theory, we analyze the symmetry properties of the lowest conduction band states and highest valence band states of GaP nanowires with different sizes and directions. The band state wave functions of the lowest conduction bands and the highest valence bands of the nanowires are evaluated by spatial probability distributions. For practical use, we fit the confinement energies of the electrons and holes in the nanowires to obtain an empirical formula.Comment: 19 pages, 10 figure

Public cloud data auditing with practical key update and zero knowledge privacy

Data integrity is extremely important for cloud based storage services, where cloud users no longer have physical possession of their outsourced files. A number of data auditing mechanisms have been proposed to solve this problem. However, how to update a cloud user\u27s private auditing key (as well as the authenticators those keys are associated with) without the user\u27s re-possession of the data remains an open problem. In this paper, we propose a key-updating and authenticator-evolving mechanism with zero-knowledge privacy of the stored files for secure cloud data auditing, which incorporates zero knowledge proof systems, proxy re-signatures and homomorphic linear authenticators. We instantiate our proposal with the state-of-the-art Shacham-Waters auditing scheme. When the cloud user needs to update his key, instead of downloading the entire file and re-generating all the authenticators, the user can just download and update the authenticators. This approach dramatically reduces the communication and computation cost while maintaining the desirable security. We formalize the security model of zero knowledge data privacy for auditing schemes in the key-updating context and prove the soundness and zero-knowledge privacy of the proposed construction. Finally, we analyze the complexity of communication, computation and storage costs of the improved protocol which demonstrates the practicality of the proposal

The role of riboflavin in decolourisation of Congo red and bioelectricity production using Shewanella oneidensis-MR1 under MFC and non-MFC conditions

Dissimilatory metal reducing bacteria can exchange electrons extracellularly and hold great promise for their use in simultaneous wastewater treatment and electricity production. This study investigated the role of riboflavin, an electron carrier, in the decolourisation of Congo red in microbial fuel cells (MFCs) using Shewanella oneidensis MR-1 as a model organism. The contribution of the membrane-bound protein MtrC to the decolourisation process was also investigated. Within the range of riboflavin concentrations tested, 20 µM was found to be the best with >95% of the dye (initial concentration 200 mg/L) decolourised in MFCs within 50 h compared to 90% in the case where no riboflavin was added. The corresponding maximum power density was 45 mW/m2. There was no significant difference in the overall decolourisation efficiencies of Shewanela oneidensis MR-1 ΔMtrC mutants compared to the wild type. However, in terms of power production the mutant produced more power (Pmax 76 mW/m2) compared to the wild type (Pmax 46 mW/m2) which was attributed to higher levels of riboflavin secreted in solution. Decolourisation efficiencies in non-MFC systems (anaerobic bottles) were similar to those under MFC systems indicating that electricity generation in MFCs does not impair dye decolourisation efficiencies. The results suggest that riboflavin enhances both decolourisation of dyes and simultaneous electricity production in MFCs