Unveiling the Colours of Cellulose Nitrate Black and White Film-based Negatives in Colonial Photography

ABSTRACT

Aiming at contributing to the preservation of black and white (B&W) film-based negatives held by Portuguese archives, four photographic collections from the first half of the twentieth century were selected for study. During the macro assessment of the collections the preservation condition and hues found in photographic negatives from the Elmano Cunha e Costa (ECC) were noticed, distinguishing this collection from the remaining ones. Additional attention was given considering that the ECC collection was formed in a colonial context in the 1930s, while the others were formed on the Portugal mainland. The ECC collection results from an ethnographic survey of Angolan tribes recorded with B&W film-based negatives. In this collection, sets of negatives with pink, lemon yellow, greenish, orange brownish, and red brownish hues were found. To identify the origin of such hues, the image layer was analysed by microscale energy-dispersive X-ray fluorescence (μ EDXRF) and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX). Additionally, to assess the base decay and its effect on the formation of hues, the plastic supports were characterized by Fourier transform infrared microscopy (μ FTIR). To complement the assessment of the film-base decay, pH was measured by using combined microelectrodes. The identification of mercury, iodine, chromium, and iron by μ EDXRF allowed correlation of the hues found in the negatives with chemical corrective treatments performed to improve the image quality. SEM-EDX confirmed those results and proved that the elements found were in the photographic emulsion layer. The results obtained are relevant since the hues identified may now be used as markers to indicate the technical work performed on colonial photography. Additionally, the visual and molecular assessment of the negatives’ supports (good to fair condition) allow proposing that the original storage conditions may have had a beneficial contribution to their present condition.     

Muscle oxygenation and EMG activity during isometric exercise in children

The aim of this study was to examine the time-course of and the relationships between muscle oxygenation, blood volume and myoelectrical manifestations during isometric exercise in children. Twelve healthy children aged 12.5 +/- 1.2 years (mean +/- s) performed an isometric knee extension at 50% of their maximal voluntary contraction (MVC) until exhaustion to assess endurance time (limit time, T(lim)). Changes in muscle oxygenation and blood volume were assessed by near infrared spectroscopy (NIRS). The root mean square (RMS) amplitude and the mean power frequency (MPF) from electromyogram (EMG) signals were obtained, as NIRS parameters, from the vastus lateralis. Mean T(lim) was 117 +/- 34 s. The muscle oxygenation and blood volume curves decreased immediately at the beginning of exercise. Maximal deoxygenation occurred at 50% T(lim), and fell by 76.9% from the resting value. Similarly, minimal blood volume was observed at 50% T(lim); it reached a plateau that lasted until the end of exercise. The kinetics of the MPF and RMS curves were inversely related to time. At the last set of exercises (after 75% T(lim)), a steeper RMS curve and an abrupt decrease in the MPF curve were observed. Significant correlations (r) between muscle oxygenation, blood volume, root mean square amplitude and mean power frequency were observed, which ranged from 0.72 to 0.99. These findings suggest that the fatigue resulting from sustained isometric exercise is related to a decrease in oxygenation and blood volume.     

Distributed Teaching Presence and Participants' Activity Profiles: a theoretical approach to the structural analysis of Asynchronous Learning Networks1

The rapid spread of learning networks based on asynchronous written communication — Asynchronous Learning Networks (ALNs) — makes it crucial to assess the possibilities offered by these new environments to facilitate and promote learning processes and learning outcomes. Our interest in this area is specifically directed towards the study of distributed teaching presence understood as the exercise of educational influence, i.e. as the help provided to each other participant in an ALN to promote individual and collective learning. We adopt a multi-method approach that integrates the structural analysis of presence (access and participation) and connectivity (reciprocity and responsiveness) with the content analysis of the participants’ contributions. This article focuses on structural analysis as a relevant and powerful tool for the study of collaborative learning in networking and asynchronous contexts. Its main objective is to show how a relevant and useful system of indicators and profiles, which identify and examine the distribution of educational influence in ALNs, can be constructed. We present the theoretical assumptions surrounding the concept of distributed teaching presence and illustrate the analysis with data from two didactic sequences in higher education. The results show that the structural analysis, when theoretically grounded and oriented, is a powerful tool for identifying different activity profiles related to different levels and modalities of the exercise of educational influence and for assessing the distributed teaching presence in learning networks. Finally, we discuss the benefits and constraints of this kind of analysis.     

Engineering Education in ERASMUS: an overview

The ERASMUS Programme has meant a leap forward in both the quality and the quantity of student exchange programmes in engineering. About 4700 engineering students will be involved in the first three years of the programme. There is a variety of organisational patterns in the inter-university co-operation programmes, ranging from bilateral exchanges of short duration (three months) to fully integrated multilateral programmes leading to a double qualification. The ERASMUS exchanges have proved to be highly beneficial to students: in addition to the basic academic training, the period abroad allows students to improve their language proficiency, obtain cultural and social enrichment, and develop important personal virtues like openness, adaptability and the ability to stand on their own feet.     

Evaluating the teaching and learning experience for the child with dyslexia in special and mainstream settings in Ireland

This study examines and evaluates special provision for pupils with dyslexia in three different settings: reading schools, reading units and mainstream support. The research focused on the teaching and learning context for pupils with dyslexia, the support teacher, the mainstream teacher and the experience of the student. The main participants were teachers and tutors supporting pupils with dyslexia, and the parents of these children. Survey methods included questionnaires, focus group discussions, interviews and quantitative data on pupils' reading attainment. In addition, a total of six schools, two representing each model of support, were selected as case studies. This article reports part of a larger survey, which evaluated the effectiveness of three models of special provision for children with dyslexia in primary school. The study shows that there are academic and social benefits for the child with dyslexia who is enrolled in a special setting. However, placement in a reading school or reading unit per se does not guarantee that a child will ‘catch up’ with his or her peers. The findings reported a similarity in the methods and practices teachers use in both mainstream and special settings. The discussion suggests that if teachers are to ‘catch them before they fall’ there are serious questions that must be asked about how we are teaching basic literacy skills. The findings suggest an urgent need for a more balanced approach to teaching reading and writing.     

Educação Integral e Pedagogia Social: Reflexões Aproximativas Com Base No Contexto Brasileiro

As relações entre as políticas educacionais no Brasil e as discussões da Pedagogia Social se evidenciam a partir da análise crítica da implementação da Educação Integral em escolas brasileiras. Neste trabalho, a abordagem da análise documental permitiu acessar os conteúdos das políticas para relacioná-lo aos fundamentos da Pedagogia Social. Uma das conclusões é que a escola e as políticas que a ela se dirigem consideram cada vez mais aspectos sociais, gerando novas demandas formativas e a outra é referente ao debate nacional atual sobre a formação dos Educadores Sociais para atuarem em diferentes espaços educativos, incluindo o escolar.     

Synergy Between On-the-job Training and Academic Education in the Case of a Newly Created Part-time Engineering Curriculum

Part-time vocational engineering curricula provide a response to a number of present-day demands related to economic developments. Their aim is to transform experienced higher technicians into engineering managers through a combination of knowledge derived from past experience in working positions and in new situations, with courses and activities in an academic institution. Synergy between the two streams can be achieved by specific means such as dual tutoring by the academic institution and the company, training in the capacity of synthesis regarding technological developments in progress, observation and analysis by the learner of his/her own work station, field research on team management and the writing of a final professional dissertation in the company.     

ENVIRONMENTAL EDUCATION IN HUNGARIAN UNIVERSITIES

Environmental catastrophes can be avoided and sustainable development can be achieved only if starting from early childhood people are educated to appreciate environmental values, to understand environmental processes, to recognize environmental risks, and to adopt environmentally conscious attitudes, as consumers, as professionals, and as citizens. The development of environmental education in Hungary over the last twenty years has been characterized by the extension of environmental education to an increasing number of university faculties and colleges. A great variety of postgraduate courses in environmental studies have been established. Environmental blocks and special environmental subjects have been integrated into general curricula. The experience gained in postgraduate courses has been applied to undergraduate courses. The principle being followed is that environmental education should be a part of all suitable disciplines at all levels, including the disciplines of the social sciences and of the humanities. Existing shortcomings stem from the highly specialized nature, the inflexibility, and other general aspects of Hungarian higher education and from the failure to pursue positive tendencies. Consequently, environmental studies have not been integrated into all possible disciplines. Except in the cases of course programmes for professional environmentalists, the environmental education offered may not be sufficiently comprehensive. Moreover, it tends to be concentrated in technical and vocational training programmes, while lagging behind in the humanities and the social sciences, except in the case of economics. Hungary must seize the opportunity offered by the PHARE (Po‐logne Hongrie Aide à la Recherche et à l'Edu‐cation)Programme of the European Communities to speed up advances in environmental education.