884 resultados para Popularity.
Resumo:
Rapid immunoanalytical screening of food and environmental samples for small molecular weight (hapten) biotoxin contaminations requires the production of antibody reagents that possess the requisite sensitivity and specificity. To date animal-derived polyclonal (pAb) and monoclonal (mAb) antibodies have provided the binding element of the majority of these assays but recombinant antibodies (rAb) isolated from in vitro combinatorial phage display libraries are an exciting alternative due to (1) circumventing the need for experimental animals, (2) speed of production in commonly used in vitro expression systems and (3) subsequent molecular enhancement of binder performance. Short chain variable fragments (scFv) have been the most commonly employed rAb reagents for hapten biotoxin detection over the last two decades but antibody binding fragments (Fab) and single domain antibodies (sdAb) are increasing in popularity due to increased expression efficiency of functional binders and superior resistance to solvents. rAb-based immunochromatographic assays and surface plasmon resonance (SPR) biosensors have been reported to detect sub-regulatory levels of fungal (mycotoxins), marine (phycotoxins) and aquatic biotoxins in a wide range of food and environmental matrices, however this technology has yet to surpass the performances of the equivalent mAb- and pAb-based formats. As such the full potential of rAb technology in hapten biotoxin detection has yet to be achieved, but in time the inherent advantages of engineered rAb are set to provide the next generation of ultra-high performing binder reagents for the rapid and specific detection of hapten biotoxins.
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Cold-pressed rapeseed oil (CPRSO) is produced when seeds from an oilseed rape crop are mechanically crushed whilst at a low temperature. CPRSO’s popularity is rapidly expanding and is now produced in most Northern European countries including both N.Ireland and ROI. The CPRSO industry is still relatively new and therefore not as widely researched as other high quality oils. Fifteen CPRSO from The UK, Ireland and France were examined to determine characteristic differences between the oils. Two samples of extra-virgin olive oil and two samples of refined rapeseed oil were also included in the investigation to assess performance against market competitors. The antioxidant potential of the oils was assessed using the ABTS and DPPH radical scavenging assays. Both unexpectedly showed that refined rapeseed oil had the highest potential whilst there was significant difference between many of the CPRSO’s. The acid value (ACOS method Cd 3d-63) ranged widely from 0.47-3.41. To predict the stability during storage, an accelerated oxidation test was carried out where the oils were placed in an oven (60°C) and peroxide value was monitored. The results showed extra-virgin olive oil underwent the least oxidation during the trial. The refined rapeseed oil suffered the worst levels of oxidation whilst the CPRSO’s performed similarly but with some variation. Fatty acid composition was investigated with GC-MS and some of the major fatty acids were found to differ significantly between producers. Minor compound analysis was achieved with extraction and identification through HPLC. All results are critically discussed and compared to relevant published studies.
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Victorian writers often claimed that the press was killing the fairy tale. In fact, it ensured the genre's popularity, bringing literary tales and folklore to the first mass readerships. Exploring penny weeklies, adult and children's monthlies, little magazines and the labour press, this innovative study is the first to combine media and fairy tale history. Bringing reading communities back into focus, Sumpter explores ingenious political uses of the fairy tale: in debates over socialism, evolution and race, and in the context of women's rights, decadence and gay culture. The book offers new insights into the popularisation of folklore and comparative science, and also recovers neglected visual material. From the fantasies of Kingsley, MacDonald and J. H. Ewing to the writings of Keir Hardie, Laurence Housman and Yeats, Sumpter reveals that the fairy tale was intimately shaped by the press, and that both were at the heart of nineteenth-century culture.
The paperback edition includes a new Preface.
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Despite the popularity of the Theory of Planned Behaviour (TPB) a lack of research assessing the efficacy of the model in understanding the health behaviour of children exists, with those studies that have been conducted reporting problems with questionnaire formulation and low to moderate internal consistencies for TPB constructs. The aim of this study was to develop and test a TPB-based measure suitable for use with primary school children aged 9 to 10 years. A mixed method sequential design was employed. In Stage 1, 7 semi-structured focus group discussions (N=56) were conducted to elicit the underlying beliefs specific to tooth brushing. Using content thematic analysis the beliefs were identified and a TPB measure was developed. A repeated measures design was employed in Stage 2 using test re-test reliability analysis in order to assess its psychometric properties. In all, 184 children completed the questionnaire. Test-retest reliabilities support the validity and reliability of the TPB measure for assessing the tooth brushing beliefs of children. Pearson’s product moment correlations were calculated for all of the TPB beliefs, achieving substantial to almost perfect agreement levels. Specifically, a significant relationship between all 10 of the direct and indirect TPB constructs at the 0.01 level was achieved. This paper will discuss the design and development of the measure so could serve as a guide to fellow researchers and health psychologists interested in using theoretical models to investigate the health and well-being of children.
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The increasing popularity of the social networking service, Twitter, has made it more involved in day-to-day communications, strengthening social relationships and information dissemination. Conversations on Twitter are now being explored as indicators within early warning systems to alert of imminent natural disasters such earthquakes and aid prompt emergency responses to crime. Producers are privileged to have limitless access to market perception from consumer comments on social media and microblogs. Targeted advertising can be made more effective based on user profile information such as demography, interests and location. While these applications have proven beneficial, the ability to effectively infer the location of Twitter users has even more immense value. However, accurately identifying where a message originated from or author’s location remains a challenge thus essentially driving research in that regard. In this paper, we survey a range of techniques applied to infer the location of Twitter users from inception to state-of-the-art. We find significant improvements over time in the granularity levels and better accuracy with results driven by refinements to algorithms and inclusion of more spatial features.
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Introduction
The use of video capture of lectures in Higher Education is not a recent occurrence with web based learning technologies including digital recording of live lectures becoming increasing commonly offered by universities throughout the world (Holliman and Scanlon, 2004). However in the past decade the increase in technical infrastructural provision including the availability of high speed broadband has increased the potential and use of videoed lecture capture. This had led to a variety of lecture capture formats including pod casting, live streaming or delayed broadcasting of whole or part of lectures.
Additionally in the past five years there has been a significant increase in the popularity of online learning, specifically via Massive Open Online Courses (MOOCs) (Vardi, 2014). One of the key aspects of MOOCs is the simulated recording of lecture like activities. There has been and continues to be much debate on the consequences of the popularity of MOOCs, especially in relation to its potential uses within established University programmes.
There have been a number of studies dedicated to the effects of videoing lectures.
The clustered areas of research in video lecture capture have the following main themes:
• Staff perceptions including attendance, performance of students and staff workload
• Reinforcement versus replacement of lectures
• Improved flexibility of learning
• Facilitating engaging and effective learning experiences
• Student usage, perception and satisfaction
• Facilitating students learning at their own pace
Most of the body of the research has concentrated on student and faculty perceptions, including academic achievement, student attendance and engagement (Johnston et al, 2012).
Generally the research has been positive in review of the benefits of lecture capture for both students and faculty. This perception coupled with technical infrastructure improvements and student demand may well mean that the use of video lecture capture will continue to increase in frequency in the next number of years in tertiary education. However there is a relatively limited amount of research in the effects of lecture capture specifically in the area of computer programming with Watkins 2007 being one of few studies . Video delivery of programming solutions is particularly useful for enabling a lecturer to illustrate the complex decision making processes and iterative nature of the actual code development process (Watkins et al 2007). As such research in this area would appear to be particularly appropriate to help inform debate and future decisions made by policy makers.
Research questions and objectives
The purpose of the research was to investigate how a series of lecture captures (in which the audio of lectures and video of on-screen projected content were recorded) impacted on the delivery and learning of a programme of study in an MSc Software Development course in Queen’s University, Belfast, Northern Ireland. The MSc is conversion programme, intended to take graduates from non-computing primary degrees and upskill them in this area. The research specifically targeted the Java programming module within the course. It also analyses and reports on the empirical data from attendances and various video viewing statistics. In addition, qualitative data was collected from staff and student feedback to help contextualise the quantitative results.
Methodology, Methods and Research Instruments Used
The study was conducted with a cohort of 85 post graduate students taking a compulsory module in Java programming in the first semester of a one year MSc in Software Development. A pre-course survey of students found that 58% preferred to have available videos of “key moments” of lectures rather than whole lectures. A large scale study carried out by Guo concluded that “shorter videos are much more engaging” (Guo 2013). Of concern was the potential for low audience retention for videos of whole lectures.
The lecturers recorded snippets of the lecture directly before or after the actual physical delivery of the lecture, in a quiet environment and then upload the video directly to a closed YouTube channel. These snippets generally concentrated on significant parts of the theory followed by theory related coding demonstration activities and were faithful in replication of the face to face lecture. Generally each lecture was supported by two to three videos of durations ranging from 20 – 30 minutes.
Attendance
The MSc programme has several attendance based modules of which Java Programming was one element. In order to assess the consequence on attendance for the Programming module a control was established. The control used was a Database module which is taken by the same students and runs in the same semester.
Access engagement
The videos were hosted on a closed YouTube channel made available only to the students in the class. The channel had enabled analytics which reported on the following areas for all and for each individual video; views (hits), audience retention, viewing devices / operating systems used and minutes watched.
Student attitudes
Three surveys were taken in regard to investigating student attitudes towards the videoing of lectures. The first was before the start of the programming module, then at the mid-point and subsequently after the programme was complete.
The questions in the first survey were targeted at eliciting student attitudes towards lecture capture before they had experienced it in the programme. The midpoint survey gathered data in relation to how the students were individually using the system up to that point. This included feedback on how many videos an individual had watched, viewing duration, primary reasons for watching and the result on attendance, in addition to probing for comments or suggestions. The final survey on course completion contained questions similar to the midpoint survey but in summative view of the whole video programme.
Conclusions and Outcomes
The study confirmed findings of other such investigations illustrating that there is little or no effect on attendance at lectures. The use of the videos appears to help promote continual learning but they are particularly accessed by students at assessment periods. Students respond positively to the ability to access lectures digitally, as a means of reinforcing learning experiences rather than replacing them. Feedback from students was overwhelmingly positive indicating that the videos benefited their learning. Also there are significant benefits to part recording of lectures rather than recording whole lectures. The behaviour viewing trends analytics suggest that despite the increase in the popularity of online learning via MOOCs and the promotion of video learning on mobile devices in fact in this study the vast majority of students accessed the online videos at home on laptops or desktops However, in part, this is likely due to the nature of the taught subject, that being programming.
The research involved prerecording the lecture in smaller timed units and then uploading for distribution to counteract existing quality issues with recording entire live lectures. However the advancement and consequential improvement in quality of in situ lecture capture equipment may well help negate the need to record elsewhere. The research has also highlighted an area of potentially very significant use for performance analysis and improvement that could have major implications for the quality of teaching. A study of the analytics of the viewings of the videos could well provide a quick response formative feedback mechanism for the lecturer. If a videoed lecture either recorded live or later is a true reflection of the face to face lecture an analysis of the viewing patterns for the video may well reveal trends that correspond with the live delivery.
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Electric vehicles (EVs) and hybrid electric vehicles (HEVs) are rapidly gaining popularity as a means of de-carbonization in the transport sector in tackling sustainable energy supply and environment pollution problems. To build a proper battery model is essential in predicting battery behaviour under various operating conditions for avoiding unsafe battery operations and developing proper controlling algorithms and maintenance strategies. This paper presents a comprehensive review of battery modelling methods. In particular, the mechanism and characteristics of Li-ion batteries are presented, and different modelling methods are discussed. Considering that equivalent electric circuit models (EECMs) are the most widely used, a detailed analysis of the modelling procedure is presented.
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With over 50 billion downloads and more than 1.3 million apps in Google’s official market, Android has continued to gain popularity amongst smartphone users worldwide. At the same time there has been a rise in malware targeting the platform, with more recent strains employing highly sophisticated detection avoidance techniques. As traditional signature based methods become less potent in detecting unknown malware, alternatives are needed for timely zero-day discovery. Thus this paper proposes an approach that utilizes ensemble learning for Android malware detection. It combines advantages of static analysis with the efficiency and performance of ensemble machine learning to improve Android malware detection accuracy. The machine learning models are built using a large repository of malware samples and benign apps from a leading antivirus vendor. Experimental results and analysis presented shows that the proposed method which uses a large feature space to leverage the power of ensemble learning is capable of 97.3 % to 99% detection accuracy with very low false positive rates.
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Quantile normalization (QN) is a technique for microarray data processing and is the default normalization method in the Robust Multi-array Average (RMA) procedure, which was primarily designed for analysing gene expression data from Affymetrix arrays. Given the abundance of Affymetrix microarrays and the popularity of the RMA method, it is crucially important that the normalization procedure is applied appropriately. In this study we carried out simulation experiments and also analysed real microarray data to investigate the suitability of RMA when it is applied to dataset with different groups of biological samples. From our experiments, we showed that RMA with QN does not preserve the biological signal included in each group, but rather it would mix the signals between the groups. We also showed that the Median Polish method in the summarization step of RMA has similar mixing effect. RMA is one of the most widely used methods in microarray data processing and has been applied to a vast volume of data in biomedical research. The problematic behaviour of this method suggests that previous studies employing RMA could have been misadvised or adversely affected. Therefore we think it is crucially important that the research community recognizes the issue and starts to address it. The two core elements of the RMA method, quantile normalization and Median Polish, both have the undesirable effects of mixing biological signals between different sample groups, which can be detrimental to drawing valid biological conclusions and to any subsequent analyses. Based on the evidence presented here and that in the literature, we recommend exercising caution when using RMA as a method of processing microarray gene expression data, particularly in situations where there are likely to be unknown subgroups of samples.
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The popularity of tri-axial accelerometer data loggers to quantify animal activity through the analysis of signature traces is increasing. However, there is no consensus on how to process the large data sets that these devices generate when recording at the necessary high sample rates. In addition, there have been few attempts to validate accelerometer traces with specific behaviours in non-domesticated terrestrial mammals.
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A number of studies have recently investigated personality traits in non-human species, with the dog gaining popularity as a subject species for research in this area. Recent research has shown the consistency of personality traits across both context and time for adult dogs, both when using questionnaire based methods of investigation and behavioural analyses of the dogs' behaviour. However, only a few studies have assessed the correspondence between these two methods, with results varying considerably across studies. Furthermore, most studies have focused on adult dogs, despite the fact that an understanding of personality traits in young puppies may be important for research focusing on the genetic basis of personality traits. In the current study, we sought to evaluate the correspondence between a questionnaire based method and the in depth analyses of the behaviour of 2-month old puppies in an open-field test in which a number of both social and non-social stimuli were presented to the subjects. We further evaluated consistency of traits over time by re-testing a subset of puppies. The correspondence between methods was high and test-retest consistency (for the main trait) was also good using both evaluation methods. Results showed clear factors referring to the two main personality traits 'extroversion,' (i.e. the enthusiastic, exuberant approach to the stimuli) and 'neuroticism,' (i.e. the more cautious and fearful approach to the stimuli), potentially similar to the shyness-boldness dimension found in previous studies. Furthermore, both methods identified an 'amicability' dimension, expressing the positive interactions the pups directed at the humans stranger, and a 'reservedness' dimension which identified pups who largely chose not to interact with the stimuli, and were defined as quiet and not nosey in the questionnaire.
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Gene expression connectivity mapping has gained much popularity recently with a number of successful applications in biomedical research testifying its utility and promise. Previously methodological research in connectivity mapping mainly focused on two of the key components in the framework, namely, the reference gene expression profiles and the connectivity mapping algorithms. The other key component in this framework, the query gene signature, has been left to users to construct without much consensus on how this should be done, albeit it has been an issue most relevant to end users. As a key input to the connectivity mapping process, gene signature is crucially important in returning biologically meaningful and relevant results. This paper intends to formulate a standardized procedure for constructing high quality gene signatures from a user’s perspective.
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Lavenders belong to the family Labiatae and represent some of the most popular medicinal plants of great economic importance. Their essential oils are important for the perfume, cosmetic, flavouring and pharmaceutical industries. However, despite its popularity, and the long tradition of use, biological properties of the various Lavandula species are not yet been well sustained by scientific or clinical studies and some available data being inconclusive and controversial [1]. Although Lavandula spp. have similar ethnobotanical properties, however, chemical composition and therapeutic uses differ from different species and main composition of essential oils showed differences with species and with the region were they grow [1,2,3]. L. stoechas L. subsps. luisieri (Rozeira) Rozeira. L. pedunculata (Mill.) Cav. and L. viridis L’Hér are endemic to the Iberian Peninsula, widespread in the South of Portugal, namely in Alentejo and Algarve. In our work, essential oils from the stems or leaves from wild grown plants of L. luisieri (Alentejo), L. pedunculata (Alentejo) and L. viridis (Algarve), were extracted by hydrodistillation and analyzed by GC-FID. Antimicrobial activity was evaluated by solid diffusion disk assay and minimal inhibitory concentration (MIC) against pathogenic Gram-positive and Gram-negative bacteria and food spoilage fungi.
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No actual contexto de competitividade, os destinos turísticos podem diferenciar-se pela imagem que os turistas e residentes têm sobre eles enquanto espaços alternativos de lazer e turismo (Baloglu & Mangaloglu, 2001). A imagem dos destinos constitui um conceito central na literatura em turismo porque está fortemente relacionada com o comportamento dos residentes e dos turistas (Baloglu & McCleary, 1999). A imagem afecta o comportamento de escolha e avaliação do destino, da viagem e da participação e experiência turísticas (Echtner and Ritchie 1991; Lee & Lee, 2009). Por outro lado, os residentes têm, também eles, uma imagem sobre o local onde residem que pode e deve ser analisada, afectando, por sua vez, a percepção que os turistas têm desses espaços (Gallarza, Saura & García, 2001). Alguns destinos turísticos possuem características simbólicas que exercem forte influência na formação da sua imagem, como são o caso dos espaços de montanha. De facto, as montanhas constituem um dos mais profundos arquétipos da Humanidade simbolizando poder, liberdade e eternidade (Smethurst, 2000, p.36). As regiões de montanha têm-se tornado num dos mais atractivos destinos turísticos constituindo a sua procura, actualmente, 20% dos fluxos turísticos globais com 500 milhões de turistas anualmente (UNEP, 2002; Thomas et al., 2006). Mas até muito recentemente, os estudos sobre os espaços de montanha limitavam-se, maioritariamente, às suas características físicas, ecológicas e ambientais (Smethurst, 2000). Uma abordagem do ponto de vista do turismo de montanha, no contexto da imagem, pode revelar-se, assim, essencial. Neste contexto, o presente estudo pretende analisar, de uma forma holística e multidisciplinar, a imagem que os residentes e turistas têm dos espaços de montanha, bem como o respectivo gap. O objectivo central é construir uma escala MDI - Mountain Destination Image Scale - no sentido de medir os parâmetros da imagem do destino, incluindo factores cognitivos e afectivos e tendo em conta os grupos populacionais turistas e residentes. Com base numa extensa revisão da literatura em imagem dos destinos turísticos e nos significados sociais e culturais da montanha ao longo do tempo, e no âmbito do trabalho empírico realizado a 315 turistas e 315 residentes na Serra da Estrela (Portugal), Alpes (França, Áustria e Suiça) e Picos da Europa (Espanha), os resultados indicam que a escala multidimensional MDI integra cinco dimensões de imagem de montanha pelos turistas: (1) histórico-cultural, (2) natural/ecológica, (3) social e prestígio, (4) lazer e desporto e (5) afectiva; e três dimensões percepcionadas pelos residentes: (1) mística/sagrada, (2) histórico-cultural e (3) afectiva. A discussão é centrada nas implicações teóricas e práticas da escala MDI no planeamento, gestão e marketing dos destinos turísticos de montanha. São igualmente apresentadas as limitações do presente estudo e traçadas algumas linhas orientadoras para investigações futuras.
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A conservação da biodiversidade nunca foi uma assunto tão popular como nas últimas décadas, mas esta popularidade crescente é devida à pior das razões: o passo acelerado da extinção de espécies e habitats. Os ecossistemas tropicais são, ao mesmo tempo, os mais diversos e os mais ameaçados, em parte porque muitos países destas regiões emergem ainda de situações de instabilidade social, económica e política. O Brasil é o maior país Neotropical, onde se encontram alguns dos biomas com maior diversidade e mais ameaçados do planeta. Actualmente, é também um país líder ao nível da planificação e implementação de medidas de conservação da biodiversidade. Vários dos biomas tropicais mais diversos e ameaçados encontram-se em território brasileiro. Dois destes biomas, a Amazónia e o Cerrado, convergem numa região ecotonal sujeita a uma elevada pressão humana, conhecida como o arco do desmatamento. O Araguaia, um dos maiores rios do Brasil, corre ao longo desta paisagem e os efeitos do desmatamento são já evidentes em toda a sua bacia. Por causa do acelerado ritmo de degradação deste ecossistema, torna-se urgente obter uma imagem clara da biodiversidade regional e compreender como e se a estratégia de conservação para esta região é capaz de lidar com as correntes ameaças e alcançar o seu objectivo a longo prazo: conservar a biota regional. Tendo a herpetofauna como grupo-alvo, os nossos objectivos principais foram: aumentar o conhecimento das comunidades de anfíbios e répteis squamata da região do curso médio do Rio Araguaia; compreender a importância deste rio nos padrões intraespecíficos de estrutura e diversidade genética para diferentes espécies com diferentes características ecológicas; avaliar o potencial de diferentes metodologias para o estudo e monitorização da herpetofauna regional. Os nossos resultados revelam que a amostragem continuada e o uso de diferentes técnicas são essenciais para a obtenção de uma imagem precisa da diversidade da herpetofauna local. As comunidades locais de anfíbios e lagartos apresentaram maior riqueza específica na Área de Protecção Ambiental Bananal/Cantão (APABC), uma área tampão, do no Parque Estadual do Cantão (PEC), uma área de conservação estrita. A APABC é caracterizada por uma maior heterogeneidade de habitats e os nosso resultados corroboram a teoria da heterogeneidade espacial e resultados recentes que revelam uma maior diversidade de lagartos nas zonas interfluviais do Cerrado, do que nas matas de galeria. Os resultados aqui apresentados não corroboram a hipótese de que os ecótonos apresentam maior diversidade do que os biomas em redor. Os nossos resultados revelaram ainda que o Rio Araguaia afecta de forma diferente a estrutura genética de várias espécies de anfíbios e lagartos. Estas diferenças poderão estar relacionadas com a ecologia das espécies, nomeadamente com o uso de diferentes habitats, a vagilidade, ou a estratégia alimentar. Sugerimos que a gestão integração de diferentes unidades de conservação, com diferentes estatutos, podem ajudar a preservar melhor a biota regional.