Effect of sintering temperature and heat treatment on electrical properties of indium oxide based ceramics

Indium oxide based ceramics with bismuth oxide addition were sintered in air in the temperature range 800-1300 ºC. Current-voltage characteristics of In2O3-Bi2O3 ceramics sintered at different temperatures are weakly nonlinear. After an additional heat treatment in air at about 200 ºC samples sintered at a temperature within the narrow range of about 1050-1100 ºC exhibit a current-limiting effect accompanied by low-frequency current oscillations. It is shown that the observed electrical properties are controlled by the grain-boundary barriers and the heat treatment in air at 200 ºC leads to the decrease in the barrier height. Electrical measurements, scanning electron microscopy and X-ray photoelectron spectroscopy results suggest that the current-limiting effect observed in In2O3-Bi2O3 can be explained in terms of the modified barrier model proposed earlier for the explanation of similar effect in In2O3-SrO ceramics

Bronchoabsorption; a novel bronchoscopic technique to improve biomarker sampling of the airway

BACKGROUND: Current techniques used to obtain lung samples have significant limitations and do not provide reproducible biomarkers of inflammation. We have developed a novel technique that allows multiple sampling methods from the same area (or multiple areas) of the lung under direct bronchoscopic vision. It allows collection of mucosal lining fluid and bronchial brushing from the same site; biopsy samples may also be taken. The novel technique takes the same time as standard procedures and can be conducted safely. METHODS: Eight healthy smokers aged 40–65 years were included in this study. An absorptive filter paper was applied to the bronchial mucosa under direct vision using standard bronchoscopic techniques. Further samples were obtained from the same site using bronchial brushings. Bronchoalveolar lavage (BAL) was obtained using standard techniques. Chemokine (C-C Motif) Ligand 20 (CCL20), CCL4, CCL5, Chemokine (C-X-C Motif) Ligand 1 (CXCL1), CXCL8, CXCL9, CXCL10, CXCL11, Interleukin 1 beta (IL-1β), IL-6, Vascular endothelial growth factor (VEGF), Matrix metalloproteinase 8 (MMP-8) and MMP-9 were measured in exudate and BAL. mRNA was collected from the bronchial brushings for gene expression analysis. RESULTS: A greater than 10 fold concentration of all the biomarkers was detected in lung exudate in comparison to BAL. High yield of good quality RNA with RNA integrity numbers (RIN) between 7.6 and 9.3 were extracted from the bronchial brushings. The subset of genes measured were reproducible across the samples and corresponded to the inflammatory markers measured in exudate and BAL. CONCLUSIONS: The bronchoabsorption technique as described offers the ability to sample lung fluid direct from the site of interest without the dilution effects caused by BAL. Using this method we were able to successfully measure the concentrations of biomarkers present in the lungs as well as collect high yield mRNA samples for gene expression analysis from the same site. This technique demonstrates superior sensitivity to standard BAL for the measurement of biomarkers of inflammation. It could replace BAL as the method of choice for these measurements. This method provides a systems biology approach to studying the inflammatory markers of respiratory disease progression. TRIAL REGISTRATION: NHS Health Research Authority (13/LO/0256)

Virtual Engineering Using Realistic Virtual Models in Brownfield Factory Layout Planning

As more pressure is put on manufacturing companies to increase productivity and reduce waste as a means to remain competitive due to increased globalization and digitalization, many companies find themselves investing in their production systems, leading to changes in their existing factories and production systems. This process is usually performed with 2D CAD drawings and data of varying quality, leading to several challenges along the way. This longitudinal research follows up on eight years of industrial studies where researchers have applied 3D laser scanning and immersive virtual reality to improve the brownfield factory layout planning processes in real industrial scenarios, a novel approach in the research field. By interviewing key stakeholders at each company and analyzing the findings, challenges in data availability and accuracy of existing data, grasping scale and perspective, and challenges gathering input and communicating around planned changes are identified and shown to be substantially alleviated by the application of the technological tools and allowing more people to be part of the factory layout planning process. By using virtual engineering, industries can improve their brownfield factory layout planning process and take wellinformed decisions leading to sustainability benefits via fewer costly mistakes, improved employee engagement, and less need for travel

Curbing Corruption in Nigeria: The Imperatives of Good Leadership

The work generally examined the past and present government leaderships' efforts at curbing corruption in Nigeria and the imperatives of good leadership. The study, specifically, analyzed the relationship between effectively fighting and curbing corruption and the leadership style in Nigeria. The basic finding is that because corruption in Nigeria is very pervasive at the nation's various leadership levels, the effort to curb it has not been significantly successful. This is because the leaders who are at the forefront of the anti-graft war are grossly embedded in corrupt activities themselves. In the face of this, the work recommends that to effectively fight and control corruption in Nigeria, government leadership at all levels must be honest, upright, sincere and accountable in their management of state affairs. Very importantly, the leaders need to exhibit exemplary attitudes and serve as models for upright and honest public and even private lives. In fact, Nigeria leaders must be willing and capable to demonstrate personal commitment to the ant-graft war not only in words but, very importantly, in deeds. This is very necessary if the efforts at fighting corruption in Nigeria are to be effective and meaningful

Measurement of filling factor 5/2 quasiparticle interference: observation of charge e/4 and e/2 period oscillations

A standing problem in low dimensional electron systems is the nature of the 5/2 fractional quantum Hall state: its elementary excitations are a focus for both elucidating the state's properties and as candidates in methods to perform topological quantum computation. Interferometric devices may be employed to manipulate and measure quantum Hall edge excitations. Here we use a small area edge state interferometer designed to observe quasiparticle interference effects. Oscillations consistent in detail with the Aharanov-Bohm effect are observed for integer and fractional quantum Hall states (filling factors 2, 5/3, and 7/3) with periods corresponding to their respective charges and magnetic field positions. With these as charge calibrations, at 5/2 filling factor and at lowest temperatures periodic transmission through the device consistent with quasiparticle charge e/4 is observed. The principal finding of this work is that in addtion to these e/4 oscillations, periodic structures corresponding to e/2 are also observed at 5/2 and at lowest temperatures. Properties of the e/4 and e/2 oscillations are examined with the device sensitivity sufficient to observe temperature evolution of the 5/2 quasiparticle interference. In the model of quasiparticle interference, this presence of an effective e/2 period may empirically reflect an e/2 quasiparticle charge, or may reflect multiple passes of the e/4 quasiparticle around the interferometer. These results are discussed within a picture of e/4 quasiparticle excitations potentially possessing non-Abelian statistics. These studies demonstrate the capacity to perform interferometry on 5/2 excitations and reveal properties important for understanding this state and its excitations.Comment: version 3 contains additional data beyond version 2, 26 pages, 8 figures PNAS 081259910

Reflections on the US College Loans System: Lessons from Australia and England

There is wide agreement that the US student loan system faces significant problems. Seven million borrowers are in default and many more are not repaying for reasons such as returning to school, or economic hardship. The stress of repayments faced by many students results at least in part from the design of US student loans. Specifically, loans are organised like a mortgage, with fixed monthly repayments over a fixed period of time, creating a high repayment burden on borrowers with low income. This paper draws on the experience of the income-contingent loan (ICL) systems operating in England and Australia, in which monthly or two-weekly repayments are related to the borrower's income in that period, thus building in automatic insurance against inability to repay during periods of low income. We discuss the design of this type of loan in detail since such an exercise seems to be largely absent in the US literature. Drawing on data from the US Current Population Survey (CPS) we provide two main empirical contributions: a stylised illustration of the revenue and distributional implications of different hypothetical ICL arrangements for the USA; and an illustration of repayment problems faced by low-earning borrowers in the US loan system, including a plausible example of adverse outcomes with respect to Stafford loans. Importantly, we compare repayment burdens under the existing and alternative systems. Our illustrations show how US mortgage-type loans can create financial difficulties for a significant minority of US borrowers, difficulties which an ICL is designed to address. We note also that the current small and ineffective income-based repayment system in the US has few of the characteristics of an ideal ICL