Mastery Learning: Improving the Model

In this paper, we report on developments in the Mastery Learning (ML) curriculum and assessment model that has been successfully implemented in a metropolitan university for teaching first-year mathematics. Initial responses to ML were positive; however, we ask whether the nature of the ML tests encourages a focus on shallow learning of procedures, and whether the structure of the assessment regime provides sufficient motivation for learning more complex problem solving. We analysed assessment data, as well as student reports and survey responses in an attempt to answer these questions

STUDIO DEL TRATTAMENTO TERMICO DI ACCIAI RAPIDI PER CILINDRI DI LAMINAZIONE A CALDO

In questo lavoro si propone lo studio del trattamento di tempra e rinvenimento di due acciai rapidi prodotti per colata centrifuga. La microstruttura dei materiali allo stato grezzo di colata è data da un reticolo più o meno interconnesso di carburi primari, in percentuale prossima al 10% in volume e da una matrice costituita da martensite e bainite. Le curve CCT evidenziano per entrambi un naso bainitico al di sotto dei 400°C per velocità di raffreddamento inferiori a 10°Cs-1. Gli acciai sono stati trattati termicamente secondo il processo impiegato a livello industriale. L’influenza della temperatura di austenitizzazione è stata valutata aumentando tale parametro da 1030 fino a 1200°C. Le relative curve di rinvenimento evidenziano un aumento sia della temperatura che della durezza di picco secondaria, differente nei due materiali considerati, indicando un effetto benefico sulla resistenza a caldo e la necessità di un rinvenimento a temperatura superiore per eliminare completamente l’austenite residua. In prossimità della temperatura più elevata (1200°C) si assiste alla rifusione di eutettici, individuando così in questo valore di temperatura un limite processuale invalicabile. Anche il tempo di austenitizzazione mostra un effetto sulla durezza dopo tempra correlabile alla differente propensione dei due materiali alla risolubilizzazione dei carburi

The health of women and girls determines the health and well-being of our modern world: A White Paper From the International Council on Women's Health Issues

The International Council on Women's Health Issues (ICOWHI) is an international nonprofit association dedicated to the goal of promoting health, health care, and well-being of women and girls throughout the world through participation, empowerment, advocacy, education, and research. We are a multidisciplinary network of women's health providers, planners, and advocates from all over the globe. We constitute an international professional and lay network of those committed to improving women and girl's health and quality of life. This document provides a description of our organization mission, vision, and commitment to improving the health and well-being of women and girls globally

Small bowel carcinomas in celiac or Crohn's disease: Distinctive histophenotypic, molecular and histogenetic patterns

Non-familial small bowel carcinomas are relatively rare and have a poor prognosis. Two small bowel carcinoma subsets may arise in distinct immune-inflammatory diseases (celiac disease and Crohn's disease) and have been recently suggested to differ in prognosis, celiac disease-associated carcinoma cases showing a better outcome, possibly due to their higher DNA microsatellite instability and tumor-infiltrating T lymphocytes. In this study, we investigated the histological structure (glandular vs diffuse/poorly cohesive, mixed or solid), cell phenotype (intestinal vs gastric/pancreatobiliary duct type) and Wnt signaling activation (β-catenin and/or SOX-9 nuclear expression) in a series of 26 celiac disease-associated small bowel carcinoma, 25 Crohn's disease-associated small bowel carcinoma and 25 sporadic small bowel carcinoma cases, searching for new prognostic parameters. In addition, non-tumor mucosa of celiac and Crohn's disease patients was investigated for epithelial precursor changes (hyperplastic, metaplastic or dysplastic) to help clarify carcinoma histogenesis. When compared with non-glandular structure and non-intestinal phenotype, both glandular structure and intestinal phenotype were associated with a more favorable outcome at univariable or stage- and microsatellite instability/tumor-infiltrating lymphocyte-inclusive multivariable analysis. The prognostic power of histological structure was independent of the clinical groups while the non-intestinal phenotype, associated with poor outcome, was dominant among Crohn's disease-associated carcinoma. Both nuclear β-catenin and SOX-9 were preferably expressed among celiac disease-associated carcinomas; however, they were devoid, per se, of prognostic value. We obtained findings supporting an origin of celiac disease-associated carcinoma in SOX-9-positive immature hyperplastic crypts, partly through flat β-catenin-positive dysplasia, and of Crohn's disease-associated carcinoma in a metaplastic (gastric and/or pancreatobiliary-type) mucosa, often through dysplastic polypoid growths of metaplastic phenotype. In conclusion, despite their common origin in a chronically inflamed mucosa, celiac disease-associated and Crohn's disease-associated small bowel carcinomas differ substantially in histological structure, phenotype, microsatellite instability/tumor-infiltrating lymphocyte status, Wnt pathway activation, mucosal precursor lesions and prognosis

Representations of happiness and life satisfaction in the group of educated and socially active young people

The paper examines the differences in the social representations of happiness among optimists and pessimists in the group of socially active, educated young members of the international youth organization Association Internationale des Etudiants en Sciences Economiques et Commerciales . To assess the degree of optimism and pessimism we used the Satisfaction With Life Scale (SWLS) developed by E. Diener, while social representation, divided into the nucleus and peripheral zones, were examined using Verges’ technique within the framework of the concept of social mindsets offered by S. Moskovichi. It has been shown that, irrespective of the optimism or pessimism of the participants, the nucleus of their representations of happiness contains such a value as love. However, only in optimists’ representations is this value combined in the nucleus with the values of family and friendship. In the pessimists’ nucleus zone of the representation of happiness, love is presented as an independent value, primarily associated with striking emotional experiences, which has aspects of psychological addiction. Considerable differences between optimists and pessimists have also been found in the peripheral zone of the representation of happiness. Only optimists have such associations as “knowledge”, “children”, and “faith” in their peripheral area. In our opinion, the major scale of differences between optimists and pessimists is formed by the factor of sociocentricity and egocentricity

The use of unmanned aerial vehicles for precision agriculture: An overview and a preliminary cost analysis

In recent years, interest in techniques and approaches capable of ensuring the efficiency and sustainability of agri-food chains has grown considerably. In this paper, we explore the opportunities offered by the use of unmanned aerial vehicles (UAVs) for precision agriculture. First of all, we provide an overview about the possible alternatives in terms of aerial platforms and sensors for image acquisition. Secondly, starting from the technical constraints, a preliminary cost analysis is carried out. We refer to a hypothetical small-medium farm in the olive sector, which wants to adopt a UAV to make its agricultural practices more efficient. In particular, we make a comparison between two types of UAV, fixed-wing and rotary-wing. The main result of our analysis is that the purchase of a UAV for own use is still quite expensive, especially if the field to be monitored is limited in size. However, the production capacity of the UAV can be better exploited if nearby farms are also served. Finally, we identify the main current limitations of UAV technology in agriculture and the possible challenges that should be faced in the future in order to achieve large-scale spread

The fabrication of stable platinum-silicon oxide multilayers for X-ray mirrors

An investigation has been carried out to determine the conditions required for the fabrication of stable SiO2-Pt multilayers using DC-magnetron sputtering for the Pt and RF-magnetron sputtering for the SiO2. As a preliminary investigation, single layers of Pt on SiO2 were analysed by X-ray reflectivity (XRR) and X-ray photoelectron spectroscopy (XPS) to develop a model of the Pt-SiO2 interface layer. The results indicated that a distinct interface layer develops as a Pt silicate approximately 6 Å thick. SiO2-Pt multilayers fabricated with a period d>65 Å using pure argon as the sputtering gas, display X-ray reflectivity patterns which can be accurately characterised by a repeating bilayer model. When d<65 Å the multilayer becomes unstable upon exposure to air. Additional peaks develop in the XRR pattern which increase in magnitude with time. These peaks arise from the expansion of the SiO2 layers in the multilayer starting from the top bilayer and gradually working through the multilayer. In the as-prepared specimens the SiO2 layers are incompletely oxidised and have a composition SiOx (x<2) and, on exposure to air, oxygen diffuses through the multilayer surface converting the SiOx to SiO2. By introducing a small partial pressure of oxygen into the sputtering gas during deposition, multilayers with d<65 Å remained stable on exposure to air. Under these conditions the density of the platinum layers determined from XRR measurements was reduced by approximately 25%. XPS showed that the platinum layer contained bonded oxygen in the form of platinum oxide PtOx (x<1). SiO2/PtOx multilayers have been fabricated with periods down to 13 Å, but the intensity of the first order peak drops off dramatically once the thickness of the PtOx layer is less that 10-12 Å. © 2002 Elsevier Science B.V. All rights reserved