Simulating the Effects of an Extended Source on the Shack-Hartmann Wavefront Sensor through Turbulence

Perspective elongation in Shack-Hartmann wavefront sensor (SHWFS) spots is a phenomenon caused by an extended three-dimensional scattering beacon in the mesosphere (80-100km). Elongated spots cause errors in wavefront sensor measurements, which leads to poor turbulence compensation and decreased image resolution of the optical system. In order to compensate for elongated spots, a proper beacon model must be developed to simulate the error. In this paper, a documented theory for modeling an elongated sodium beacon and elongated SHWFS spots using sodium layer slices was tested. It was found that nine evenly-spaced slices were adequate to model the elongated beacon in the most stringent, turbulence-included case. Furthermore bench-top source was developed and tested to model SHWFS spot elongation in the lab. The source demonstrated the principle, but requires a more robust design to simulate sodium layer depth. Being the first documented experiment using an extended source on an adaptive optics (AO) system, it opens the door for more research to include: the effects of deep turbulence on AO systems and correlation based wavefront sensing with extended sources

Institutions, Demography, and Economic Growth

This article evaluates criticisms by Sarah G. Carmichael, Alexandra de Pleijt, Jan Luiten van Zanden, and Tine De Moor of our view of the European Marriage Pattern (EMP), and explains why their claims are incorrect. We elaborate our arguments concerning the institutional sources of economic growth, explore the relationship between women's position and the EMP, analyze the two-way links between demographic and economic behavior, and explicate aspects of our empirical analysis that these scholars find puzzling. The causes of European economic growth, we reiterate, are not to be found in the EMP but rather must be sought in the wider framework of nonfamilial institutions.</jats:p

Using probe electrospray ionization mass spectrometry and machine learning for detecting pancreatic cancer with high performance

A rapid blood-based diagnostic modality to detect pancreatic ductal adenocarcinoma (PDAC) with high accuracy is an unmet medical need. The study aimed to validate a unique diagnosis system using Probe Electrospray Ionization Mass Spectrometry (PESI-MS) and Machine Learning to the diagnosis of PDAC. Peripheral blood samples were collected from a total of 322 consecutive PDAC patients and 265 controls with a family history of PDAC. Five µl of serum samples were analyzed using PESI-MS system. The mass spectra from each specimen were then fed into machine learning algorithms to discriminate between control and cancer cases. A total of 587 serum samples were analyzed. The sensitivity of the machine learning algorithm using PESI-MS profiles to identify PDAC is 90.8% with specificity of 91.7% (95% CI 83.9%-97.4% and 82.8%-97.7% respectively). Combined PESI-MS profiles with age and CA19-9 as predictors, the accuracy for stage 1 or 2 of PDAC is 92.9% and for stage 3 or 4 is 93% (95% CI 86.3-98.2; 87.9-97.4 respectively). The accuracy and simplicity of the PESI-MS profiles combined with machine learning provide an opportunity to detect PDAC at an early stage and must be applicable to the examination of at-risk populations. [Abstract copyright: AJTR Copyright © 2020.

Goals of Community Colleges in Canada A 1987 Perspective

Community colleges in Canada are characterized by diversity with respect to their relations with the government, the scope and range of their programs, and the ways in which they respond to societal needs. Nevertheless, the colleges all share a commitment to providing access to a wide range of individuals who need educational opportunities beyond secondary school. This study examines the goals of community colleges in Canada as perceived by two key groups - chief executive officers, and government personnel in each province who are responsible for college development. The prime purpose was to determine the degree to which these individuals agree on the rating and ranking of their goals and the variations which exist among the provincial systems. The results indicate that provincial college systems have continued to emphasize the goals which characterized their early development and reflect the differences in priorities which occur by province. While the two groups showed a high level of agreement in each region, a range of priorities existed within each group. In general, the study provided a restatement of the diversity of ways in which Canada's colleges are attempting to contribute to the economic, sociocultural, and educational development of the nation.Ce qui cartactérise le mieux les collèges communautaires, c'est leur diversité, dont les relations avec le gouvernement, la portée et l'étendue des programmes ainsi que la façon dont ils répondent aux besoins de la société sont autant de variables. Cependant les collèges communautaires ont tous en commun l'engage-ment qu'ils ont pris d'accueillir des personnes très diverses ayant toutes besoin de suivre des cours après l'école secondaire. Cette étude examine les objectifs des collèges communautaires au Canada tels que les conçoivent deux groupes essentiels : les directeurs généraux d'une part, et d'autre part, les fonctionnaires chargés du perfectionnement des collèges dans chaque province. Le but premier de cette recherche était de déterminer dans quelle mesure ces deux groupes sont d'accord sur les objectifs à atteindre et sur ceux qui ont un caractère prioritaire, et aussi de montrer s'il y a des différences entre les systèmes des diverses provinces. Les résultats obtenus indiquent que les collèges communautaires continuent à promouvoir les objectifs qui ont contribué à leur création; ils montrent aussi que l'on accorde la priorité à des objectifs différents selon les provinces. Même si les deux groupes interrogés semblaient tout à fait d'accord dans toutes les régions, on a pu remarquer qu'on accordait un caractère primordial à des objectifs très différents au sein de chaque groupe. D'une façon générale, cette étude a permis de réaffirmer que c'est par des moyens fort divers que les collèges communautaires du Canada participent au progrès de la nation, tant du point de vue éducatif et écomomique que socioculturel

Practising Inclusive Citation in Modern Languages Research: The View from Brazilian Film Studies

As Modern Languages researchers and teachers we pride ourselves on our ability to read (and view) material beyond the Anglo-American canon, and we make use of this ability to argue that we offer fresh perspectives on theory and practice within the broad range of sub-disciplines that our subject area encompasses. As Modern Languages researchers, inclusive citation should, then, be our bread and butter. But to what extent are we really contributing to “decolonised” knowledge creation? How much attention, for example, are we paying to calls to #CiteBlackWomen? Taking as a case study my recent explorations of race and gender in Brazilian cinema, I offer some reflections on the impact that citing more inclusively has made on my understanding of Brazilian culture more broadly