2,605 research outputs found
Some aspects of geological information contained in LANDSAT images
The characteristics of MSS images and methods of interpretation are analyzed from a geological point of view. The supportive role of LANDSAT data are illustrated in several examples of surface expressions of geological features, such as synclines and anticlines, spectral characteristics of lithologic units, and circular impact structures
The innovative behaviour of tourism firms
Tourism is a growing and an extremely competitive sector. To be competitive, tourism firms need do innovate, responding to the more and more demanding tourist. Nonetheless, research on this field is limited and insufficient. In Portugal, the tourism sector is a highly strategic sector for the Portuguese economy, but there is no evidence on how Portuguese tourism firms innovate. This paper presents a thesis proposal with the aim to provide empirical evidence of the innovative behaviour of Portuguese tourism firm. Trough a direct survey on all the Portuguese tourism firms we intent to investigate firms’ innovativeness and their determinants and then compare the results with data from Danish and Spanish tourism firms. The literature on innovation in services and in tourism, in particular Sunbdo et al. (2007) taxonomy of tourism firms, provides us a guide to our investigation. It is also our aim to contribute with additional findings on the process of innovation in the tourism industry.Innovation, Tourism Industries, Portugal
Single Stellar Populations in the Near-Infrared - I. Preparation of the IRTF spectral stellar library
We present a detailed study of the stars of the IRTF spectral library to
understand its full extent and reliability for use with Stellar Population (SP)
modeling. The library consist of 210 stars, with a total of 292 spectra,
covering the wavelength range of 0.94 to 2.41 micron at a resolution R = 2000.
For every star we infer the effective temperature (Teff), gravity (logg) and
metallicity ([Z/Zsun]) using a full-spectrum fitting approach in a section of
the K band (2.19 to 2.34 micron) and temperature-NIR colour relations. We test
the flux calibration of these stars by calculating their integrated colours and
comparing them with the Pickles library colour-temperature relations. We also
investigate the NIR colours as a function of the calculated effective
temperature and compared them in colour-colour diagrams with the Pickles
library. This latter test shows a good broad-band flux calibration, important
for the SP models. Finally, we measure the resolution R as a function of
wavelength. We find that the resolution increases as a function of lambda from
about 6 angstrom in J to 10 angstrom in the red part of the K-band. With these
tests we establish that the IRTF library, the largest currently available
general library of stars at intermediate resolution in the NIR, is an excellent
candidate to be used in stellar population models. We present these models in
the next paper of this series.Comment: 17 pages, 19 figures. Accepted for publication in Astronomy and
Astrophysic
An online survey of UK women's attitudes to having children, the age they want children and the effect of the COVID-19 pandemic
STUDY QUESTION: What are women's views on having children, including the age they want to have them and other influences such as the coronavirus disease 2019 (COVID-19) pandemic? SUMMARY ANSWER: Women's views on having children, at their preferred age of 30 years, included their maternal urge and concerns about their biological clock and stability, while 19% said COVID-19 had affected their views. WHAT IS KNOWN ALREADY: Women globally are delaying the birth of their first child, with the average age of first birth approaching 32 years in some countries. The average age women have their first child in the UK is 30.7 years and over 50% of women aged 30 years are childless. The fertility rate stands at 1.3 in several European Union countries. Some people are not having their desired family size or are childless by circumstance. It is essential to understand people's attitudes to having children in different countries to identify trends so we can develop educational resources in an age-appropriate manner. STUDY DESIGN, SIZE, DURATION: We conducted an anonymous, online survey of multiple choice and open-ended questions. The survey was live for 32 days from 15 May 2020 to 16 June 2020 and was promoted using social media. PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 887 women from 44 countries participated in the survey. After filtering out women who did not consent, gave blank or incomplete responses, and those not in the UK, 411 responses remained. From the data, three areas of questioning were analysed: their views on having children, the ideal age they want to have children and the effects of the COVID-19 pandemic. Qualitative data were analysed by thematic analysis. MAIN RESULTS AND THE ROLE OF CHANCE: The average age (±SD) of the women who completed the survey was 32.2 years (±5.9), and they were mainly heterosexual (90.8%) and 84.8% had a university education. One-third of women were married/in a civil partnership (37.7%) and 36.0% were cohabitating. In relation to their views on having children, the main themes identified were: the maternal urge, the ticking of the biological clock, why did no one teach us this?, the need for stability and balance in their life, pressure to start a family and considering other ways to have a family. When asked 'In an ideal world, at what age approximately would you like to have had or have children?' a normal distribution was observed with a mean age of 29.9 (±3.3) years. When asked 'What factors have led you to decide on that particular age?' the most frequent choice was 'I am developing my career'. Three themes emerged from the qualitative question on why they chose that age: the need for stability and balance in their life, the importance of finding the right time and life experiences. The majority of women felt that the COVID-19 pandemic had not affected their decision to have children (72.3%), but 19.1% said it had. The qualitative comments showed they had concerns about instability in their life, such as finances and careers, and delays in fertility treatment. LIMITATIONS, REASONS FOR CAUTION: The survey was promoted on social media only and the women who answered the survey were highly educated. WIDER IMPLICATIONS OF THE FINDINGS: The women surveyed ideally want children at age 30 years but there are obstacles in their way, such as the need to develop their career. Global tailored fertility education is essential to ensure people make informed reproductive choices. In addition, it is essential for supportive working environments and affordable childcare to be in place in every country. STUDY FUNDING/COMPETING INTEREST(S): J.C.H. is founder of www.globalwomenconnected.com and Reproductive Health at Work, and author of the book Your Fertile Years. This project was funded by the Institute for Women's Health, UCL. TRIAL REGISTRATION NUMBER: N/A
Secuencia de enseñanza sobre el electromagnetismo
In orden to plan the teaching sequence of any physical topic, we consider essential to bear in mind three factors, at least: the scientific problems that arise from the subjects to be studied, the conceptions of the students to whom the teaching is addressed, and above all, the strategies and methodological process to be taken. This paper presents the didactic model, based on a constructivist approach, we use, the university students' conceptions about electromagnetism, the conceptual map where we make explicit our points of view of the concepts we work on, and the group activities we have designed in order to promote the conceptual, methodological and attitudinal change
Transcriptomic analysis of the hepatic response to stress in the red cusk-eel (Genypterus chilensis): Insights into lipid metabolism, oxidative stress and liver steatosis
Indexación: Scopus.Teleosts exhibit a broad divergence in their adaptive response to stress, depending on the magnitude, duration, and frequency of stressors and the species receiving the stimulus. We have previously reported that the red cusk-eel (Genypterus chilensis), an important marine farmed fish, shows a physiological response to stress that results in increased skeletal muscle atrophy mediated by over-expression of components of the ubiquitin proteasome and autophagy-lysosomal systems. To better understand the systemic effects of stress on the red cusk-eel metabolism, the present study assessed the transcriptomic hepatic response to repetitive handling-stress. Using high-Throughput RNA-seq, 259 up-regulated transcripts were found, mostly associated with angiogenesis, gluconeogenesis, and triacylglyceride catabolism. Conversely, 293 transcripts were down-regulated, associated to cholesterol biosynthesis, PPARα signaling, fatty acid biosynthesis, and glycolysis. This gene signature was concordant with hepatic metabolite levels and hepatic oxidative damage. Moreover, the increased plasmatic levels of AST (aspartate aminotransferase), ALT (alanine aminotransferase) and AP (alkaline phosphatase), as well as liver histology suggest stress-induced liver steatosis. This study offers an integrative molecular and biochemical analysis of the hepatic response to handling-stress, and reveals unknown aspects of lipid metabolism in a non-model teleost.http://journals.plos.org/plosone/article?id=10.1371/journal.pone.017644
Predictors of Poststroke Depression: a Retrospective Study in a Rehabilitation Unit
INTRODUÇÃO/OBJECTIVOS: O Acidente Vascular Cerebral (AVC) pode limitar de forma
importante a funcionalidade. As complicações psiquiátricas têm sido identificadas como factores determinantes na reabilitação pós-AVC, sendo a Depressão a complicação psiquiátrica mais frequente e a que está associada a pior prognóstico. Subsiste ainda incerteza quanto à sua etiologia e factores de risco. Na revisão sistemática mais recente, reconhecem-se como factores
preditivos a gravidade do AVC, o grau de incapacidade do doente e o défice cognitivo. Questões metodológicas impediram a determinação de outros factores. Assim, urge definir novos factores que facilitem um diagnóstico atempado, que possa diminuir os efeitos negativos sobre o processo de reabilitação.
Objectivos: determinação da incidência da Depressão de novo pós-AVC (DPA) e o estudo
das variáveis descritas na literatura como possíveis factores preditivos de DPA: sexo, idade, tipo de AVC, lateralidade, território vascular e presença de afasia. Foi definido como endpoint secundário o estudo do tipo de afasia.
MATERIAIS E MÉTODOS: Estudo longitudinal retrospectivo, envolvendo todos os doentes
admitidos no internamento de um Serviço de MFR com o diagnóstico de AVC de novo, entre
1-1-2009 e 31-12-2009. Foram colhidos elementos demográficos e clínicos dos processos clínicos, num total de 74 doentes. Critérios de exclusão: ‘AVC prévio’, ‘Doença psiquiátrica com perturbação do humor prévia’ e ‘Medicação antidepressiva à data do AVC’. Para o tratamento estatístico usou-se o SPSS 11.5.
RESULTADOS: A incidência da DPA observada foi de 44,6%. Dos possíveis factores preditivos testados, apenas a presença de afasia apresentou uma relação estatisticamente significativa com a depressão (p=0.02). Não se encontrou relação com o tipo de afasia. Os restantes factores
preditivos testados não mostraram correlação estatística significativa. Parece existir uma relação entre o sexo masculino e a DPA (p=0.07), que não atingiu significância no tamanho da amostra conseguido (n).
CONCLUSÕES: Este estudo estabelece a afasia como factor preditivo da DPA. A elevada incidência de DPA nesta população particular concorda com os estudos existentes, sendo necessário outro tipo de estudo que permita justificar o valor encontrado. São necessários mais estudos não só para aumentar o conhecimento dos factores de risco para a DPA, como para melhorar
os resultados dos programas de reabilitação
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