The differential expression of alternatively polyadenylated transcripts is a common stress-induced response mechanism that modulates mammalian mRNA expression in a quantitative and qualitative fashion

Stress adaptation plays a pivotal role in biological processes and requires tight regulation of gene expression. In this study, we explored the effect of cellular stress on mRNA polyadenylation and investigated the implications of regulated polyadenylation site usage on mammalian gene expression. High-confidence polyadenylation site mapping combined with global pre-mRNA and mRNA expression profiling revealed that stress induces an accumulation of genes with differentially expressed polyadenylated mRNA isoforms in human cells. Specifically, stress provokes a global trend in polyadenylation site usage toward decreased utilization of promoter-proximal poly(A) sites in introns or ORFs and increased utilization of promoter-distal polyadenylation sites in intergenic regions. This extensively affects gene expression beyond regulating mRNA abundance by changing mRNA length and by altering the configuration of open reading frames. Our study highlights the impact of post-transcriptional mechanisms on stress-dependent gene regulation and reveals the differential expression of alternatively polyadenylated transcripts as a common stress-induced mechanism in mammalian cells

A Theoretical Model of Augmented Reality Acceptance in Urban Cultural Heritage Tourism

Latest mobile technologies have revolutionised the way people experience their environment. Recent research explored the opportunities of using augmented reality (AR) in order to enhance the user experience however, there is only limited research on users’ acceptance of AR in the tourism context. The technology acceptance model is the predominant theory for researching technology acceptance. Previous researchers used the approach of proposing external dimensions based on secondary literature; however missed the opportunity to integrate context specific dimensions. This paper therefore aims to propose an AR acceptance model in the context of urban heritage tourism. Five focus groups, with young British female tourists visiting Dublin and experiencing a mobile AR application, were conducted. The data were analysed using thematic analysis and revealed seven dimensions that should be incorporated into AR acceptance research including information quality, system quality, costs of use, recommendations, personal innovativeness and risk as well as facilitating conditions

Volume Rendering Mathematical Models and Algorithmic Aspects

In this paper various algorithms for rendering gaseous phenomena are reviewed. In computer graphics such algorithms are used to model natural scenes containing clouds, fog, ames and so on. On the other hand displaying three dimensional scalar datasets as cloudy objects has become an important technique in scienti c visualization. Our emphasis is on this latter subject of so-called direct volume rendering. All algorithms will be discussed within the framework of linear transport theory. The equation of transfer is derived. This equation is suitable to describe the radiation eld in a participating medium where absorption, emission, and scattering of light can occur. Almost all volume rendering algorithms can be shown to solve special cases of the equation of transfer. Related problems like the mapping from data values to model parameters or possible parallelization strategies will be discussed as well.

Augmented reality systems for weed economic thresholds applications Tecnologia de realidade ampliada para utilização com os níveis de dano econômico de plantas daninhas

The augmented reality (AR) technology has applications in many fields as diverse as aeronautics, tourism, medicine, and education. In this review are summarized the current status of AR and it is proposed a new application of it in weed science. The basic algorithmic elements for AR implementation are already available to develop applications in the area of weed economic thresholds. These include algorithms for image recognition to identify and quantify weeds by species and software for herbicide selection based on weed density. Likewise, all hardware necessary for AR implementation in weed science are available at an affordable price for the user. Thus, the authors propose weed science can take a leading role integrating AR systems into weed economic thresholds software, thus, providing better opportunities for science and computer-based weed control decisions.<br>A tecnologia de realidade aumentada (AR) tem aplicações em vários e diversos campos, como aeronáutica, turismo, medicina e educação. Nesta revisão, é resumido o estado atual da AR e propõe-se uma nova aplicação dela na ciência das plantas daninhas. Os elementos básicos para a implementação de algoritmos de AR já estão disponíveis para desenvolvimento de aplicações na área de níveis de dano econômico de plantas daninhas. Estes incluem algoritmos de reconhecimento de imagem, para identificar e quantificar as infestantes por espécie; e software, para a seleção de herbicidas com base na densidade de plantas daninhas. Da mesma forma, todo o hardware necessário para aplicação da AR nessa área da ciência das plantas daninhas está disponível a um preço acessível ao usuário. Assim, sugere-se que a ciência das plantas daninhas possa assumir um papel preponderante na integração dos sistemas de AR aos softwares de níveis de dano econômico de plantas daninhas nas culturas. Com isso, seria possível proporcionar melhor utilização da informática para apoio nas decisões de controle de plantas daninhas baseadas na ciência