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Jornalismo e colaboração : a participação do profissional e do amador na construção da notícia no canal VC Repórter

Becker, Marcelo Miranda
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Trabalho de Conclusão de Curso Formato: application/pdf
POR
Relevância na Pesquisa
45.91%
Este trabalho busca identificar a contribuição do internauta e do jornalista profissional na produção de notícias no vc repórter, canal de webjornalismo colaborativo do portal Terra, partindo da hipótese de que ambos têm papéis distintos neste processo. Inicialmente, são apresentados os principais conceitos teóricos a respeito de webjornalismo, teoria da cauda longa, movimento Pro-Am e webjornalismo colaborativo, tendo como referências obras de autores como Mielniczuk (2003), Anderson (2006), Belochio (2009), Primo (2007), Landow (1997) e Gillmor (2005). Após a apresentação do contexto atual dos grandes portais brasileiros e de seus respectivos espaços de webjornalismo colaborativo, são analisados os manuais de redação e instruções, direcionados aos jornalistas e colaboradores vc repórter, respectivamente. O objetivo é identificar as responsabilidades na produção de conteúdo jornalístico. A amostra da pesquisa a campo é composta por 43 notícias publicadas no vc repórter. A partir de um estudo descritivo, é possível identificar as fontes das informações citadas – com base na classificação de Charaudeau (2007) e Machado (2002) – e, assim, conclui-se que ao internauta cabe, prioritariamente, a indicação de fatos novos e o fornecimento gratuito de fotos...

Blogs de moda : evidências da Cauda Longa

Spanhol, Renata da Silva
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Trabalho de Conclusão de Curso Formato: application/pdf
POR
Relevância na Pesquisa
46.12%
Este trabalho aborda a manifestação das três forças da teoria da Cauda Longa – democratização das ferramentas de produção, democratização das ferramentas de distribuição e ligação entre oferta e demanda – nos blogs de moda Hoje Vou Assim Off, Futilish e A Casa Está Cheia de Flores. Apresenta aspectos da história do jornalismo de moda, desde o seu surgimento nos veículos impressos até sua presença na mídia digital. A seguir, trata da teoria de Chris Anderson (2006), que explica como a tecnologia permite que qualquer pessoa seja produtor e distribuidor de conteúdo, e a relaciona com os blogs. Por fim, aponta elementos de cada uma das três forças da Cauda Longa nos blogs estudados, buscando, para isso, exemplos nos posts, comentários, tipos de publicidade veiculados e reportagens em outros meios de comunicação. Constata que os blogs de moda participam da dinâmica da Cauda Longa sendo um produto e ao mesmo tempo dão visibilidade a outros produtos do mercado de nicho.; This paper deals with the manifestation of the three forces of the Long Tail theory - democratization of production tools, democratization of distribution tools and link between supply and demand - in the fashion blogs Hoje Vou Assim Off , Futilish and A Casa Está Cheia de Flores. Presents aspects of the history of fashion journalism...

Cauda longa: uma análise para setores

Barbosa, Bruno Guarato
Fonte: Universidade Federal de Santa Catarina Publicador: Universidade Federal de Santa Catarina
Tipo: Trabalho de Conclusão de Curso Formato: 63 f.
PT_BR
Relevância na Pesquisa
46.04%
TCC (Graduação) - Universidade Federal de Santa Catarina. Centro Socioeconômico. Curso de Graduação em Ciências Econômicas.; O rápido crescimento da Economia Digital está transformando muitos negócios da Economia Tradicional. O que a economia da escassez pode aprender a partir da observação da economia da abundância e o que acontecerá quando tudo no mundo se tornar disponível para todos? Esta pesquisa busca conceituar a Teoria da Cauda Longa, de Chris Anderson (2006), à luz da Economia e da gestão organizacional (Administração e Marketing) para então analisar dois distintos setores tradicionais diante das condições da teoria “digital”. O setor Automobilístico brasileiro e o setor da Aviação Civil brasileira, ambos no ano de 2011, serão analisados sob aspectos mercadológicos para observar se há características em comum entre estes setores e a teoria em questão. O resultado foi avaliado a partir de pesquisa bibliográfica e análise empírica, concluindo que a Economia Tradicional desses setores analisados tem mais em comum com a Economia Digital do que era esperado, mas ainda assim pode explorar melhor a modernidade do estilo de vida atual com conceitos reunidos na Teoria da Cauda Longa.; The fast growth of Digital Economy is transforming many Traditional Economy businesses. What shortage economy can learn from observing the abundance economy and what is going to happen when everything in the world becomes available to everyone? This research seeks to conceptualize the Long Tail Theory...

A component of the side tail fiber of Escherichia coli bacteriophage lambda can functionally replace the receptor-recognizing part of a long tail fiber protein of the unrelated bacteriophage T4.

Montag, D; Schwarz, H; Henning, U
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /08/1989 EN
Relevância na Pesquisa
46.15%
The distal part of the long tail fiber of Escherichia coli bacteriophage T4 consists of a dimer of protein 37. Dimerization requires the catalytic action of protein 38, which is encoded by T4 and is not present in the virion. It had previously been shown that gene tfa of the otherwise entirely unrelated phage lambda can functionally replace gene 38. Open reading frame (ORF) 314, which encodes a protein that exhibits homology to a COOH-terminal area of protein 37, is located immediately upstream of tfa. The gene was cloned and expressed in E. coli. An antiserum against the corresponding polypeptide showed that it was present in phage lambda. The serum also reacted with the long tail fibers of phage T4 near their free ends. An area of the gene encoding a COOH-terminal region of ORF 314 was recombined, together with tfa, into the genome of T4, thus replacing gene 38 and a part of gene 37 that codes for a COOH-terminal part of protein 37. Such T4-lambda hybrids, unlike T4, required the presence of outer membrane protein OmpC for infection of E. coli B. An ompC missense mutant of E. coli K-12, which was still sensitive to T4, was resistant to these hybrids. We conclude that the ORF 314 protein represents a subunit of the side tail fibers of phage lambda which probably recognize the OmpC protein. ORF 314 was designated stf (side tail fiber). The results also offer an explanation for the very unusual fact that...

An open reading frame in the Escherichia coli bacteriophage lambda genome encodes a protein that functions in assembly of the long tail fibers of bacteriophage T4.

Montag, D; Henning, U
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /12/1987 EN
Relevância na Pesquisa
46%
Assembly of the long tail fibers of the Escherichia coli bacteriophage T4 requires the catalytic action of two auxiliary proteins. It was found that a gene of the entirely unrelated phage lambda codes for a protein which can substitute for one of these T4 polypeptides, protein 38. The lambda gene was designated tfa (tail fiber assembly). Protein 38 consists of 183 residues, and the Tfa protein consists of 194 residues; the two polypeptides are about 40% homologous. Although the tfa gene is dispensable for the growth of phage lambda, these results indicate that it may have a function in lambda morphogenesis.

Long tail kinetics in biophysics?

Nagle, J F
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /08/1992 EN
Relevância na Pesquisa
46.14%
Long tail kinetics describe a variety of data from complex, disordered materials that cannot be described by conventional kinetics. It is suggested that the kinetics of diffusive motion in complex biological media, such as cytoplasm or biomembranes, might also have long tails. The effects of long tail kinetics are investigated for two standard biophysical measurements, fluorescence recovery after photobleaching (FRAP), and dynamic light scattering (DLS). It is shown that long tail kinetic data would yield significantly distorted and misleading results when analyzed assuming conventional kinetics.

Structure of the bacteriophage T4 long tail fiber receptor-binding tip

Bartual, Sergio G.; Otero, José M.; Garcia-Doval, Carmela; Llamas-Saiz, Antonio L.; Kahn, Richard; Fox, Gavin C.; van Raaij, Mark J.
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46%
Bacteriophages are the most numerous organisms in the biosphere. In spite of their biological significance and the spectrum of potential applications, little high-resolution structural detail is available on their receptor-binding fibers. Here we present the crystal structure of the receptor-binding tip of the bacteriophage T4 long tail fiber, which is highly homologous to the tip of the bacteriophage lambda side tail fibers. This structure reveals an unusual elongated six-stranded antiparallel beta-strand needle domain containing seven iron ions coordinated by histidine residues arranged colinearly along the core of the biological unit. At the end of the tip, the three chains intertwine forming a broader head domain, which contains the putative receptor interaction site. The structure reveals a previously unknown beta-structured fibrous fold, provides insights into the remarkable stability of the fiber, and suggests a framework for mutations to expand or modulate receptor-binding specificity.

Stability versus Neuronal Specialization for STDP: Long-Tail Weight Distributions Solve the Dilemma

Gilson, Matthieu; Fukai, Tomoki
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 07/10/2011 EN
Relevância na Pesquisa
46%
Spike-timing-dependent plasticity (STDP) modifies the weight (or strength) of synaptic connections between neurons and is considered to be crucial for generating network structure. It has been observed in physiology that, in addition to spike timing, the weight update also depends on the current value of the weight. The functional implications of this feature are still largely unclear. Additive STDP gives rise to strong competition among synapses, but due to the absence of weight dependence, it requires hard boundaries to secure the stability of weight dynamics. Multiplicative STDP with linear weight dependence for depression ensures stability, but it lacks sufficiently strong competition required to obtain a clear synaptic specialization. A solution to this stability-versus-function dilemma can be found with an intermediate parametrization between additive and multiplicative STDP. Here we propose a novel solution to the dilemma, named log-STDP, whose key feature is a sublinear weight dependence for depression. Due to its specific weight dependence, this new model can produce significantly broad weight distributions with no hard upper bound, similar to those recently observed in experiments. Log-STDP induces graded competition between synapses...

If We Share Data, Will Anyone Use Them? Data Sharing and Reuse in the Long Tail of Science and Technology

Wallis, Jillian C.; Rolando, Elizabeth; Borgman, Christine L.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 23/07/2013 EN
Relevância na Pesquisa
45.91%
Research on practices to share and reuse data will inform the design of infrastructure to support data collection, management, and discovery in the long tail of science and technology. These are research domains in which data tend to be local in character, minimally structured, and minimally documented. We report on a ten-year study of the Center for Embedded Network Sensing (CENS), a National Science Foundation Science and Technology Center. We found that CENS researchers are willing to share their data, but few are asked to do so, and in only a few domain areas do their funders or journals require them to deposit data. Few repositories exist to accept data in CENS research areas.. Data sharing tends to occur only through interpersonal exchanges. CENS researchers obtain data from repositories, and occasionally from registries and individuals, to provide context, calibration, or other forms of background for their studies. Neither CENS researchers nor those who request access to CENS data appear to use external data for primary research questions or for replication of studies. CENS researchers are willing to share data if they receive credit and retain first rights to publish their results. Practices of releasing, sharing, and reusing of data in CENS reaffirm the gift culture of scholarship...

La aplicación de la teoría "The Long Tail" al escenario digital latinoamericano

Requejo Alemán, José Luis
Fonte: Universidade Carlos III de Madrid Publicador: Universidade Carlos III de Madrid
Tipo: info:eu-repo/semantics/submittedVersion; info:eu-repo/semantics/conferenceObject
Publicado em //2008 SPA
Relevância na Pesquisa
45.91%
Actas de las Jornadas del Foro Universitario de Investigación en Comunicación. (10. 2008. Madrid)

Long Tail or Steep Tail? A Field Investigation into How Online Popularity Information Affects the Distribution of Customer Choices

Tucker, Catherine; Zhang, Juanjuan
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Tipo: Trabalho em Andamento
EN_US
Relevância na Pesquisa
66.27%
The internet has made it easier for customers to find and buy a wide variety of products. This may lead to a "long tail" effect as more customers buy low-volume products. However, the internet has also made it easier for customers to find out which products are most popular. This could lead to a "steep tail" effect as customers flock towards the most popular products. Using data from a field experiment with a website that lists wedding service vendors, we find empirical evidence that a steep tail exists. The most popular vendors become more popular when customers can easily observe previous customers' click-through behavior. Then, we ask whether this steep tail effect "complements" the long tail, by attracting customers who would otherwise have chosen nothing, or "competes with" the long tail, by shifting customers from less popular vendors to popular ones. We find evidence of a complementary effect, where the steep tail indicates new interest in the most popular vendors from outside, with negligible cannibalization of interest for less popular vendors. The findings suggest that popularity information can serve as a powerful marketing tool that facilitates product category growth. They also explain the prevalence of firm practices to highlight bestsellers.

The “long tail” of the protein tumbling correlation function: observation by 1H NMR relaxometry in a wide frequency and concentration range

Roos, Matthias; Hofmann, Marius; Link, Susanne; Ott, Maria; Balbach, Jochen; Rössler, Ernst; Saalwächter, Kay; Krushelnitsky, Alexey
Fonte: Springer Netherlands Publicador: Springer Netherlands
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.18%
Inter-protein interactions in solution affect the auto-correlation function of Brownian tumbling not only in terms of a simple increase of the correlation time, they also lead to the appearance of a weak slow component (“long tail”) of the correlation function due to a slowly changing local anisotropy of the microenvironment. The conventional protocol of correlation time estimation from the relaxation rate ratio R1/R2 assumes a single-component tumbling correlation function, and thus can provide incorrect results as soon as the “long tail” is of relevance. This effect, however, has been underestimated in many instances. In this work we present a detailed systematic study of the tumbling correlation function of two proteins, lysozyme and bovine serum albumin, at different concentrations and temperatures using proton field-cycling relaxometry combined with R1ρ and R2 measurements. Unlike high-field NMR relaxation methods, these techniques enable a detailed study of dynamics on a time scale longer than the normal protein tumbling correlation time and, thus, a reliable estimate of the parameters of the “long tail”. In this work we analyze the concentration dependence of the intensity and correlation time of the slow component and perform simulations of high-field 15N NMR relaxation data demonstrating the importance of taking the “long tail” in the analysis into account.

Bootstrapping the Long Tail in Peer to Peer Systems

Huberman, Bernardo A.; Wu, Fang
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 08/12/2005
Relevância na Pesquisa
45.91%
We describe an efficient incentive mechanism for P2P systems that generates a wide diversity of content offerings while responding adaptively to customer demand. Files are served and paid for through a parimutuel market similar to that commonly used for betting in horse races. An analysis of the performance of such a system shows that there exists an equilibrium with a long tail in the distribution of content offerings, which guarantees the real time provision of any content regardless of its popularity.

Long-Tail Feature of DNA Words Over- and Under-Representation in Coding Sequences

Nowicka, A.; Dudek, M. R.; Cebrat, S.; Kowalczuk, M.; Mackiewicz, P.; Dudkiewicz, M.; Szczepanik, D.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 20/02/2001
Relevância na Pesquisa
45.99%
We have analyzed DNA sequences of known genes from 16 yeast chromosomes (Saccharomyces cerevisiae) in terms of oligonucleotides. We have noticed that the relative abundances of oligonucleotide usage in the genome follow a long-tail Levy-like distribution. We have observed that long genes often use strongly over-represented and under-represented nucleotides, whereas it was not the case for the short genes (shorter than 300 nucleotides) under consideration. If selection on the extremely over-represented/under-represented oligonucleotides was strong, long genes would be more affected by spontaneous mutations than short ones.; Comment: 5 figures

Mathematical analysis of long tail economy using stochastic ranking processes

Hattori, Kumiko; Hattori, Tetsuya
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 11/04/2008
Relevância na Pesquisa
45.91%
We present a new method of estimating the distribution of sales rates of, e.g., book titles at an online bookstore, from the time evolution of ranking data found at websites of the store. The method is based on new mathematical results on an infinite particle limit of the stochastic ranking process, and is suitable for quantitative studies of the long tail structure of online retails. We give an example of a fit to the actual data obtained from Amazon.co.jp, which gives the Pareto slope parameter of the distribution of sales rates of the book titles in the store.

Long-tail Behavior in Locomotion of Caenorhabditis elegans

Ohkubo, Jun; Yoshida, Kazushi; Iino, Yuichi; Masuda, Naoki
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
46.04%
The locomotion of Caenorhabditis elegans exhibits complex patterns. In particular, the worm combines mildly curved runs and sharp turns to steer its course. Both runs and sharp turns of various types are important components of taxis behavior. The statistics of sharp turns have been intensively studied. However, there have been few studies on runs, except for those on klinotaxis (also called weathervane mechanism), in which the worm gradually curves toward the direction with a high concentration of chemicals; this phenomenon was discovered recently. We analyzed the data of runs by excluding sharp turns. We show that the curving rate obeys long-tail distributions, which implies that large curving rates are relatively frequent. This result holds true for locomotion in environments both with and without a gradient of NaCl concentration; it is independent of klinotaxis. We propose a phenomenological computational model on the basis of a random walk with multiplicative noise. The assumption of multiplicative noise posits that the fluctuation of the force is proportional to the force exerted. The model reproduces the long-tail property present in the experimental data.; Comment: 30 pages, 11 figures, some errors were corrected

Shelf space strategy in long-tail markets

Bentley, R. Alexander; Ormerod, Paul; Madsen, Mark E.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
46.12%
The Internet is known to have had a powerful impact on on-line retailer strategies in markets characterised by long-tail distribution of sales. Such retailers can exploit the long tail of the market, since they are effectively without physical limit on the number of choices on offer. Here we examine two extensions of this phenomenon. First, we introduce turnover into the long-tail distribution of sales. Although over any given period such as a week or a month, the distribution is right-skewed and often power law distributed, over time there is considerable turnover in the rankings of sales of individual products. Second, we establish some initial results on the implications for shelf-space strategy of physical retailers in such markets.; Comment: 10 pages, 3 figures

Challenging the Long Tail Recommendation

Yin, Hongzhi; Cui, Bin; Li, Jing; Yao, Junjie; Chen, Chen
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 30/05/2012
Relevância na Pesquisa
46.29%
The success of "infinite-inventory" retailers such as Amazon.com and Netflix has been largely attributed to a "long tail" phenomenon. Although the majority of their inventory is not in high demand, these niche products, unavailable at limited-inventory competitors, generate a significant fraction of total revenue in aggregate. In addition, tail product availability can boost head sales by offering consumers the convenience of "one-stop shopping" for both their mainstream and niche tastes. However, most of existing recommender systems, especially collaborative filter based methods, can not recommend tail products due to the data sparsity issue. It has been widely acknowledged that to recommend popular products is easier yet more trivial while to recommend long tail products adds more novelty yet it is also a more challenging task. In this paper, we propose a novel suite of graph-based algorithms for the long tail recommendation. We first represent user-item information with undirected edge-weighted graph and investigate the theoretical foundation of applying Hitting Time algorithm for long tail item recommendation. To improve recommendation diversity and accuracy, we extend Hitting Time and propose efficient Absorbing Time algorithm to help users find their favorite long tail items. Finally...

Software Engineering as Instrumentation for the Long Tail of Scientific Software

Huang, Daisie; Lapp, Hilmar
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 06/09/2013
Relevância na Pesquisa
46.18%
The vast majority of the long tail of scientific software, the myriads of tools that implement the many analysis and visualization methods for different scientific fields, is highly specialized, purpose-built for a research project, and has to rely on community uptake and reuse for its continued development and maintenance. Although uptake cannot be controlled over even guaranteed, some of the key factors that influence whether new users or developers decide to adopt an existing tool or start a new one are about how easy or difficult it is to use or enhance a tool for a purpose for which it was not originally designed. The science of software engineering has produced techniques and practices that would reduce or remove a variety of barriers to community uptake of software, but for a variety of reasons employing trained software engineers as part of the development of long tail scientific software has proven to be challenging. As a consequence, community uptake of long tail tools is often far more difficult than it would need to be, even though opportunities for reuse abound. We discuss likely reasons why employing software engineering in the long tail is challenging, and propose that many of those obstacles could be addressed in the form of a cross-cutting non-profit center of excellence that makes software engineering broadly accessible as a shared service...

A Universal Carrier Test for the Long Tail of Mendelian Disease

Balaji S. Srinivasan; Jason Flannick; A. Scott Patterson; Christopher C. Chang; Tuan Pham; Sharon Young; Amit Kaushal; James J. Lee; Pasquale Patrizio; Eric A. Evans
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Manuscript
Relevância na Pesquisa
46.12%
*Background:* Mendelian disorders are individually rare but collectively common, forming a "long tail" of genetic disease. More than 20 million people worldwide suffer from a disease in this long tail before the age of 25, with minorities and developing countries at highest risk and with the number of carriers far in excess of this figure. Importantly, the Jewish community’s campaign for universal Tay-Sachs screening shows that these incurable diseases can nevertheless be prevented if carrier status is known before conception. A single highly-accurate assay for the long tail of Mendelian disease would allow us to scale this successful campaign up to the general population, thereby improving millions of lives, greatly benefiting minority health, and saving billions of dollars. *Methods and Findings:* We have addressed the need for such an assay by designing the Universal Genetic Test (UNIT), a non-invasive, saliva-based carrier test for more than 100 Mendelian diseases across all major population groups. We exhaustively validated the test with a median of 147 positive and 525 negative samples per variant. By combining probes for risk alleles with family history information...