792 research outputs found
Sol-gel technology for ecological dyeing cellulosic of fibres
Dyeing cellulosic fibres with reactive dyes wastes great quantities of salt and water.
The objective of this work is to dye cellulosic fibers using coloured nanoparticles (CNPs) as an alternative to dyeing with reactive dyes, without salt and with only a short washing-off procedure at the end of dyeing.
Samples of cotton were dyed by exhaustion with CNPs at light to medium colours. Washfastness results are given. Complete Washing-off sequence after dyeing was not necessary for the red and yellow colours, only one rinsing. The blue colour needs some washing off since the fastness is lower than for the other colours even though soaping is not necessary, saving energy and time relative to dyeing with reactive dyes
Diffusion of coloured silica nanoparticles into human hair
A novel method for dyeing human hair fibres using coloured silica nanoparticles of 206 nm has been
developed. Diffusion of coloured silica nanoparticles into hair fibres has been investigated; silica
nanoparticles do not penetrate at all, or do so only sparingly, into the structure of Caucasian virgin hair.
However, coloured silica nanoparticles diffused readily into bleached hair fibres. Scanning electron
microscopy showed that coloured silica nanoparticles were present mainly in the outer regions of the
hair structure (the inner layers of the cuticle and the outer region of the cortex). It was found that the
silica nanoparticles were physically entrapped in the hair fibres and results showed a good shampoo
fastness to washing
Single side damage simulations and detection in beam-like structures
Beam-like structures are the most common components in real engineering, while single side damage is often encountered. In this study, a numerical analysis of single side damage in a free-free beam is analysed with three different finite element models; namely solid, shell and beam models for demonstrating their performance in simulating real structures. Similar to experiment, damage is introduced into one side of the beam, and natural frequencies are extracted from the simulations and compared with experimental and analytical results. Mode shapes are also analysed with modal assurance criterion. The results from simulations reveal a good performance of the three models in extracting natural frequencies, and solid model performs better than shell while shell model performs better than beam model under intact state. For damaged states, the natural frequencies captured from solid model show more sensitivity to damage severity than shell model and shell model performs similar to the beam model in distinguishing damage. The main contribution of this paper is to perform a comparison between three finite element models and experimental data as well as analytical solutions. The finite element results show a relatively well performanc
Brincando com formas geométricas e cores: Um pé no Triângulo… Uma mão no Pentágono...
Neste artigo é analisada a construção do conhecimento matemático num jardim de infância do Porto, através do jogo; em particular, tratamos as formas
geométricas e os diagramas de Carroll. Estes temas foram abordados, de uma forma integrada, numa atividade que também envolveu a expressão motora. Esta
estratégia revelou-se uma boa forma de motivar as crianças do grupo para conteúdos complexos. Debruçamo-nos neste artigo sobre as fases de observação, planificação, ação e avaliação da atividade. Concluímos que os objetivos traçados
foram ao encontro das necessidades e interesses das crianças e que a atividade
contribuiu para o seu desenvolvimento integral e integrado.In this paper we talk about the building of mathematical knowledge at a public kindergarten, in Porto, through game play; in particular, we address the
geometric shapes and Carroll diagrams. These issues were addressed in a joint manner, in an activity that also covered motor expression. This strategy turned out
to be useful for motivating preschoolers and engaging them in activities involving
complex contents. This text is focused on observation, planning, implementation
and evaluation of the activity. We concluded that the targets we set met the
needs and interests of children, and that the activity contributed to their overall
development
Do Concreto para o Abstrato pelo Uso dos Sentidos e de Sensores: Um Estudo de Caso sobre o Ecossistema Poças de Maré
Este artigo apresenta um estudo de caso exploratório, desenvolvido no contexto
do Projeto Sondar e Sentir o Ambiente para Desenvolver o Pensamento Abstrato (SOS Abstrato), que visa estudar as potencialidades da utilização conjunta
e sinérgica dos sentidos humanos e de sensores eletrónicos para desenvolver
o pensamento abstrato nas crianças. O estudo de caso foi desenvolvido com uma turma do 4.º ano de escolaridade e centrado no ecossistema Poças de
Maré de uma praia no Norte de Portugal. A utilização dos sentidos e sensores em
atividades experimentais produziu evidências de desenvolvimento da abstração
no estudo da biodiversidade e da temperatura.This paper presents an exploratory case study, developed in the context of
the Using Sensors and Sensing in the Environment to Develop Abstract Thinking
Project (SOS Abstract), which goal is to study the potential of the joint and
synergic use of electronic sensors and human senses to develop children’s
abstract thinking. The case study was developed with a 4th year class and is
centred on the Tide Pools of a beach in the North of Portugal. The use of senses and sensors in experimental activities produced evidences of the development of
abstract thinking, while studying biodiversity and temperature
Reabilitação da Linha do Tâmega – Ponte de Baia
Percorrer a Linha do Tâmega é entender como no passado expressavam o saber
que detinham e como transmitiam o seu estilo de vida.
Esta linha, pertencente à Linha do Douro, surgiu para servir Amarante e as Terras
de Basto, mas representa também uma das imagens de marca da cidade de
Amarante, ela é um dos seus patrimónios que se encontra agora devoluto.
O presente trabalho de projecto, foca-se na linha entre a Livração e Amarante,
mais concretamente na Ponte de Baia, com o objectivo de reabilitar a zona da
ponte e a margem do rio, recuperando um território perdido e assim favorecer o
turismo, o desporto, a economia local e o lazer.
De uma forma geral, trata-se de tornar uma zona abandonada, num foco de
turismo, onde se possa contemplar a paisagem, envolver pessoas e o rio, realizar
percursos para peões e ciclistas, praticar desportos radicais.
O projecto foi realizado de forma a devolver e fornecer equipamentos e
infraestruturas para uma cidade mais dinâmica, mais cultural e mais vincada nas
suas origens
Nurses' Perceptions of Clinical Decision Making in relation to Patients in Pain
Clinical decision-making (CDM) research has focused on diagnostic reasoning, CDM models, factors influencing CDM and the development of expertise. The research approaches used, including phenomenology, have not addressed the question of how CDM is perceived and approached by nurses. This study describes perceptions of CDM in relation to patients in pain using a phenomenographic methodology. At semi-structured interviews, participants were asked to recall their responses to a situation involving a patient in pain. The responses fell into four categories: (1) the effect of the clinical environment; (2) the role of other health professionals; (3) the place of the patient; and (4) the role of experience. Examples of differences in perceptions that were likely to impact on the nurses� approach to CDM include: the ongoing effects of time and workload demands on CDM; nurses are initially dependent but were eventually able to make decisions autonomously; the patient who may be peripheral or central to CDM; and the nurses� move from the use of theoretical principles to experiential knowledge as reflection-on-practice is employed. Perceptions in all categories are strongly implicated in the nurses� sense of confidence and independence. Implications for nursing practice and nursing education suggested by the findings relate to the number of areas in which graduates work in the first year of practice, the size of new graduate workloads, graduate transition programs, the place of reflection-on-practice and undergraduate (UG) program clinical experience patterns. Among issues for further research arising from the study are: replication of the study; detailed examination of the development of CDM in the first year of nursing practice and during UG nursing education programs; the role of other health professionals in the development of CDM behaviour; the links between CDM and clinical knowledge development; and the type of clinical environments that foster confidence and independence. A conclusion of the study is that the way CDM is approached is influenced by the amount, quality, relevancy and recency of clinical experience. In this study, phenomenography was shown to be an appropriate approach to the description of nurses� perceptions of CDM in relation to patients in pain. In addition, nurses� changing perceptions over two years and the subsequent effect on CDM behaviour were described
Rugoscopy in human identification: a study in a sample of twins
Palatal rugae patterns can be useful for forensic identification purposes. However, some doubts persist in concerning the pattern singularity in twins. The purpose of this study was to assess palatal rugae pattern singularity in a sample of twins. To do this, the palatal rugae patterns of 19 pairs of monozygotic twins and 47 pairs of dizygotic twins were studied. Our results showed that in monozygotic twins, no statistical significant differences were found, either in the form or number of palatal rugae. However, in dizygotic twins, differences were found in the number or shape of all palatal rugae (except for the shape of the first two right ones), suggesting that the palatal rugae pattern can be useful for identification purposes of dizygotic, but not of monozygotic, twins.Generation XXI was funded by Programa Operacional de Saúde (Regional Department of Ministry of Health). It has support from the Portuguese Foundation for Science and Technology (FCT) and from the Calouste Gulbenkian Foundation.An individual grant to Braga S (SFRH/BD/120500/2016) by the Portuguese Foundation for Science and Technology (FCT) is gratefully acknowledged.This work was financed by FEDER (Fundo Europeu de Desenvolvimento Regional) funds through the COMPETE 2020 – Operacional Programme for Competitiveness and Internationalisation (POCI), Portugal 2020, and by Portuguese funds through FCT – Fundação para a Ciência e a Tecnologia/Ministério da Ciência, Tecnologia e Ensino Superior in the framework of the project PTDC/MEC-MCI/29777/2017/POCI-01-0145-FEDER-029777
Comparing and predicting inconsistency on positive and negative life experiences reports: which variables matter?
Most studies about life experiences and their long-term impact have relied on retrospective assessments and cross-sectional designs. However, there are concerns about the inconsistency of reports, which have been addressed in a limited scope. This study aimed to compare differences on inconsistency between positive and negative experiences to describe potential patterns and to identify sociodemographic, experiences-related and design-related predictors of inconsistency. Adults from community (N = 171) reported their life experiences twice, through self-report or interview. An overall trend of overreporting was found for positive and negative experiences. Additionally, inconsistency on positive experiences was higher than on negative although both variables were correlated. Regarding predictors of inconsistency, the model explained greater variance for negative experiences than for the positive ones. Nevertheless, most variables did not predict inconsistency, with few exceptions: impact for positive experiences, total of experiences for negative experiences, and time interval was marginally significant for both. Available data comparing inconsistency on positive and negative experiences as well as associated predictors are incipient. Overall, it seems that we know more about variables not involved in inconsistency than those that matter. Due to its relevancy, this issue should be further examined.This manuscript is part of a doctoral dissertation which had the support of the Portuguese Foundation for Science and Technology (FCT), through the PhD grant with the reference
SFRH/BD/6022/2011, funded by POPH-QREN-Typology 4.1-Advanced Training–reimbursed by the
European Social Fund and national funds from State Budget. This study was conducted at the Psychology Research Centre (CIPsi/UM) School of Psychology, University of Minho, supported by the Foundation for Science and Technology (FCT) through the Portuguese State Budget (UIDB/01662/2020)
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