Electron beam induced damage in PECVD Si3N4 and SiO2 films on InP

Phosphorus rich plasma enhanced chemical vapor deposition (PECVD) of silicon nitride and silicon dioxide films on n-type indium phosphide (InP) substrates were exposed to electron beam irradiation in the 5 to 40 keV range for the purpose of characterizing the damage induced in the dielectic. The electron beam exposure was on the range of 10(exp -7) to 10(exp -3) C/sq cm. The damage to the devices was characterized by capacitance-voltage (C-V) measurements of the metal insulator semiconductor (MIS) capacitors. These results were compared to results obtained for radiation damage of thermal silicon dioxide on silicon (Si) MOS capacitors with similar exposures. The radiation induced damage in the PECVD silicon nitride films on InP was successfully annealed out in an hydrogen/nitrogen (H2/N2) ambient at 400 C for 15 min. The PECVD silicon dioxide films on InP had the least radiation damage, while the thermal silicon dioxide films on Si had the most radiation damage

Ariel - Volume 12 Number 1

Executive Editors David G. Polin Larry H. Pastor Business Manager Alex Macones Jean Lien Editorial Page Editor Sam Markind Photography Editors Ken Yonemura Lois Leach Sports Editor Todd Hoove

Confirmation of Radish Isolate of Turnip mosaic virus in India through biological and serological evidences

Background and Objective: Oilseed brassica are one of the most exploited agricultural commodities in International trade with diversified use in human and animal consumption besides their potential use in producing green energy in the form of biofuels. Turnip mosaic virus is one of the limiting factors for declining oil content in brassica. The present studies were therefore conducted to confirm the presence of this important virus in brassica through biological and serological assays. Materials and Methods: A total of 518 samples collected from 84 locations spanning across 5 states and 1 union territory from symptomatic plants were collected and assayed in DAS-ELISA using Turnip mosaic virus (TuMV) specific polyclonal antiserum. Biological and serological host range of the virus isolate was established and different varieties/breeding lines of oilseed brassica were screened for developing a resistance panel against TuMV. Results: Turnip mosaic virus incidence ranged between 0.6-8.3% in oilseed brassica and 0.2-17.6% in crucifer vegetables. Turnip mosaic virus was recorded in very high concentration from radish as indicated by the optical density values. Mustard variety Tender Green was established as the best propagative host of Indian radish isolate of Turnip mosaic virus. Out of 32 varieties/breeding lines of oilseed brassica collected from different sources in India, 25 varieties/lines were found to be susceptible to Turnip mosaic virus under glasshouse conditions and DAS-ELISA further confirmed these findings. Conclusion: A radish isolate of Turnip mosaic virus has been identified on the basis of biological and serological assays and results obtained for screening of brassica germplasm against Turnip mosaic virus are expected to help in ascertaining the sources of resistance against this virus

A decision theoretic approach towards planning of proof load tests

Accurate determination of the bearing capacity of bridges is of high importance for society. Concerns are raised about the actual bearing capacity of bridges due to aging related deterioration, ever increasing traffic loads and conservative design. Proof load testing is often used for evaluations of bridge capacity. However, extensive proof load tests tend to be costly. Further, the risks of damage to the bridge imply that a proof load test may not always be cost effective. The performance of proof load testing and its outcomes is further dependent on factors such as the chosen loading, the monitoring technology and methods, and the stop criteria. A decision theoretic approach is utilized to demonstrate the optimal strategy for proof load testing procedures and collection of information. The decision scenario constituting the planning and performance of the proof loading is considered along with prevention of damage to the bridge. The decision maker is the proof loading planner who chooses the loading, the monitoring technologies and methods as well as the stop criteria to minimize the expected costs of the test and to comply with acceptable risks. A case study is developed and the optimal strategy with respect to loading, monitoring technology and stop criteria is identified as those with the maximum utility to the decision maker.The financial support and assistance from the Danish Road Directorate is greatly acknowledged

Genome-wide survival analysis of age at onset of alcohol dependence in extended high-risk COGA families.

BackgroundThe age at onset of alcohol dependence (AD) is a critical moderator of genetic associations for alcohol dependence. The present study evaluated whether single nucleotide polymorphisms (SNPs) can influence the age at onset of AD in large high-risk families from the Collaborative Study on the Genetics of Alcoholism (COGA).MethodsGenomewide SNP genotyping was performed in 1788 regular drinkers from 118 large European American families densely affected with alcoholism. We used a genome-wide Cox proportional hazards regression model to test for association between age at onset of AD and SNPs.ResultsThis family-based analysis identified an intergenic SNP, rs2168784 on chromosome 3 that showed strong evidence of association (P=5×10(-9)) with age at onset of AD among regular drinkers. Carriers of the minor allele of rs2168784 had 1.5 times the hazard of AD onset as compared with those homozygous for the major allele. By the age of 20 years, nearly 30% of subjects homozygous for the minor allele were alcohol dependent while only 19% of those homozygous for the major allele were. We also identified intronic SNPs in the ADP-ribosylation factor like 15 (ARL15) gene on chromosome 5 (P=1.11×10(-8)) and the UTP20 small subunit (UTP20) gene on chromosome 12 (P=4.32×10(-8)) that were associated with age at onset of AD.ConclusionsThis extended family based genome-wide cox-proportional hazards analysis identified several loci that might be associated with age at onset of AD

Challenges Related to Probabilistic Decision Analysis for Bridge Testing and Reclassification

This paper reviews historical developments and recent challenges in full scale bridge testing and introduces results- and hypotheses related to an ongoing bridge testing research project. This research project encompasses full scale bridge testing in conjunction with bearing capacity analysis as well as related contact- and non-contact monitoring procedures combined with a decision analytical approach. Results from the first steps of the project, focusing on full scale load testing of bridges, are presented. The next part approaches the interfaces between three project areas namely the bearing capacity analysis, the utilization of monitoring procedures and a decision analytical approach. The proposed probabilistic decision analysis approach is described for two scenarios: (1) The decision support for the actual proof load test providing decision rules for a safe and efficient in-situ test and (2) for the identification of efficient strategies for the bridge reclassification accounting for modeling, simulation, and monitoring information. The paper concludes with a summary highlighting deemed challenges in the used approaches