Dispersed Fringe Sensing Analysis - DFSA

Dispersed Fringe Sensing (DFS) is a technique for measuring and phasing segmented telescope mirrors using a dispersed broadband light image. DFS is capable of breaking the monochromatic light ambiguity, measuring absolute piston errors between segments of large segmented primary mirrors to tens of nanometers accuracy over a range of 100 micrometers or more. The DFSA software tool analyzes DFS images to extract DFS encoded segment piston errors, which can be used to measure piston distances between primary mirror segments of ground and space telescopes. This information is necessary to control mirror segments to establish a smooth, continuous primary figure needed to achieve high optical quality. The DFSA tool is versatile, allowing precise piston measurements from a variety of different optical configurations. DFSA technology may be used for measuring wavefront pistons from sub-apertures defined by adjacent segments (such as Keck Telescope), or from separated sub-apertures used for testing large optical systems (such as sub-aperture wavefront testing for large primary mirrors using auto-collimating flats). An experimental demonstration of the coarse-phasing technology with verification of DFSA was performed at the Keck Telescope. DFSA includes image processing, wavelength and source spectral calibration, fringe extraction line determination, dispersed fringe analysis, and wavefront piston sign determination. The code is robust against internal optical system aberrations and against spectral variations of the source. In addition to the DFSA tool, the software package contains a simple but sophisticated MATLAB model to generate dispersed fringe images of optical system configurations in order to quickly estimate the coarse phasing performance given the optical and operational design requirements. Combining MATLAB (a high-level language and interactive environment developed by MathWorks), MACOS (JPL s software package for Modeling and Analysis for Controlled Optical Systems), and DFSA provides a unique optical development, modeling and analysis package to study current and future approaches to coarse phasing controlled segmented optical systems

Does type 2 diabetes influence the risk of oesophageal adenocarcinoma?

Since hyperinsulinaemia may promote obesity-linked cancers, we compared type 2 diabetes prevalence among oesophageal adenocarcinoma (OAC) patients and population controls. Diabetes increased the risk of OAC (adjusted odds ratio 1.59, 95% confidence interval (CI) 1.04–2.43), although the risk was attenuated after further adjusting for body mass index (1.32, 95% CI 0.85–2.05)

Law, Social Norms and Welfare as Means of Public Administration: Case Study of Mahalla Institutions in Uzbekistan

Despite numerous challenges, since its independence, Uzbekistan, with the exception of the May 2005 Andijan events, has enjoyed extraordinary political stability and not recorded any considerable cases of interethnic or interfaith conflict, regime change or civil war, whereas neighboring Kyrgyzstan, labeled an “island of democracy” by the Western world, has experienced numerous conflicts and chaos, ranging from “color revolutions” to ethnic conflict. However, for understanding Uzbekistan’s ability to cope with internal and external challenges, little recourse is made to the post-independence discourse on public administration known as “mahalla reforms”. In spite of the significant existing body of literature on the mahalla, there has been little systematic scholarly investigation of the role of mahalla in maintaining political stability and security in Uzbekistan. Previous studies did not provide an account of how the law, social norms and welfare come to interplay in the mahalla system and how this influences the public administration developments in Uzbekistan. This paper begins to redress this lacuna by analyzing public-administration reforms in post-independence Uzbekistan, namely mahalla reforms, with an effort to show how political and social stability is established through mahalla, and to what extent those reforms have affected the position of individuals vis-à-vis the public-administration system. In undertaking this task, the paper employs three theoretical concepts: the theory of norms, the welfare-pentagon model and the theory of social control. In this paper, I argue that public-administration reforms since 1991 have transformed mahalla into a comprehensive system of social control; and therefore, mahalla can be places of democratic involvement or sites of authoritarianism in Uzbekistan

Quality of life following radiofrequency ablation of dysplastic Barrett’s esophagus

The impact of the diagnosis and treatment of dysplastic Barrett’s esophagus (BE) on quality of life (QoL) is poorly understood. This study assessed the influence of dysplastic BE on QoL and evaluated if endoscopic treatment of dysplastic BE with radiofrequency ablation (RFA) improves QoL

Radiofrequency Ablation of Barrett's Esophagus Reduces Esophageal Adenocarcinoma Incidence and Mortality in a Comparative Modeling Analysis

No Abstract Availabl

The CHEK2*1100delC mutation has no major contribution in oesophageal carcinogenesis

In response to DNA damage, the cell cycle checkpoint kinase 2 (CHEK2) may phosphorylate p53, Cdc25A and Cdc25C, and regulate BRCA1 function, leading to cell cycle arrest and DNA repair. The truncating germline mutation CHEK2*1100delC abrogates kinase activity and confers low-penetrance susceptibility to breast cancer. We found CHEK2*1100delC in 0.5% of 190 oesophageal squamous cell carcinomas and in 1.5% of 196 oesophageal adenocarcinomas. In addition, we observed the mutation in 3.0% of 99 Barrett's metaplasias and 1.5% of 66 dysplastic Barrett's epithelia, both known precursor lesions of oesophageal adenocarcinoma. Since CHEK2*1100delC mutation frequencies did not significantly differ among oesophageal squamous cell carcinomas, adenocarcinomas and (dysplastic) Barrett's epithelia, as compared to healthy individuals, we conclude that the CHEK2*1100delC mutation has no major contribution in oesophageal carcinogenesis

Different perceptions of the burden of upper GI endoscopy: an empirical study in three patient groups

Background: Few studies have evaluated patients' perceived burden of cancer surveillance tests. Cancer screening and surveillance, however, require a large number of patients to undergo potentially burdensome tests with only some experiencing health gains from it. We investigated the determinants of patients' reported burden of upper gastrointestinal (GI) endoscopy by comparing data from three patient groups. Patients and methods: A total of 476 patients were included: 180 patients under regular surveillance for Barrett esophagus (BE), a premalignant disorder; 214 patients with non-specific upper GI symptoms (NS), and 82 patients recently diagnosed with upper GI cancer (CA). We assessed pain, discomfort and overall burden experienced during endoscopy, symptoms in the week afterwards and psychological distress over time (Hospital Anxiety and Depression scale and Impact of Event Scale). Results: Two-thirds (66%) of patients reported discomfort and overall burden of upper GI endoscopy. Only 23% reported any pain. BE patients reported significantly less discomfort, pain and overall burden than the other patients: those with NS reported more discomfort, CA patients more pain, and both more overall burden. These differences could be statistically explained by the number of previous endoscopies and whether sedation was provided or not, but not by patient characteristics. Conclusion: The perception of upper GI endoscopy varies by patient group, due to potential adaptation after multiple endoscopies and aspects of th

Trends in the incidence of adenocarcinoma of the oesophagus and cardia in the Netherlands 1989–2003

Over the 15-year period 1989–2003, the incidence of oesophagus–cardia adenocarcinoma in the Netherlands rose annually by 2.6% for males and 1.2% for females. This was the net outcome of annual increases in the incidence of adenocarcinoma of the oesophagus (ACO) of 7.2% for males and 3.5% for females and annual declines in the incidence of adenocarcinoma of the gastric cardia (AGC) of more than 1% for both genders. Nonlinear cohort patterns were found in females with ACO and for both genders in AGC; a nonlinear period pattern was observed only in males with AGC. These differing epidemiological patterns for ACO and AGC do not support a common aetiology. Proposed underlying factors for the rise in ACO incidence appear to have little effect on AGC incidence. This and the secular decline in smoking among males may have led to the decline in AGC incidence