Self-Similarity of Friction Laws

The change of the friction law from a mesoscopic level to a macroscopic level is studied in the spring-block models introduced by Burridge-Knopoff. We find that the Coulomb law is always scale invariant. Other proposed scaling laws are only invariant under certain conditions.}Comment: Plain TEX. Figures not include

Trust your guts? The effect of gut section on diet composition and impact of Mus musculus on islands using metabarcoding

Research Article1. DNA metabarcoding is widely used to characterize the diet of species, and it becomes very relevant for biodiversity conservation, allowing the understanding of trophic chains and the impact of invasive species. The need for cost-effective biodiversity monitoring methods fostered advances in this technique. One question that arises is which sample type provides a better diet representation. 2. Therefore, with this study, we intended to evaluate if there were differences in diet estimates according to the section of the gastrointestinal tract analysed and which section(s) provided the best diet representation. Additionally, we intended to infer the ecological/economic impacts of an invader as a model of the potential effects in an originally mammal-free ecosystem. 3. We examined the gut contents of the house mouse Mus musculus introduced to Cabo Verde, considering three sections: stomach, small intestine, and large intestine. We applied a DNA-metabarcoding approach using two genetic markers, one specific for plants and another for invertebrates. 4. We showed that this invader consumed 131 taxa (73 plants and 58 invertebrates). We obtained significant differences in the composition of two of the three sections, with a higher incidence of invertebrates in the stomach and plants in the intestines. This may be due to stomach inhibitors acting on plants and/or to faster absorption of soft-body invertebrates compared to the plant fibers in the intestines. We verified that the impact of this invader in the ecosystem is predominantly negative, as at least 50% of the ingested items were native, endemic, or economically important taxa, and only 19% of the diet items were exotics 5. Overall, results showed the need to analyse only two gastrointestinal tract sections to obtain robust diet data, increasing the cost-effectiveness of the method. Furthermore, by uncovering the native taxa most frequently preyed on by mice, this DNA-metabarcoding approach allowed us to evaluate efficiently which are at the highest riskinfo:eu-repo/semantics/publishedVersio

Antibiofilm effect of some main components of essentials oils on E. coli biofilm

Fundação para a Ciência e Tecnologia (FCT)European Community - fund FEDER, through Program COMPETE, Project PTDC/SAUESA/6460912006 /FCOMP-01-0124-FEDER-00748

IsomiR_Window : a system for analyzing small‑RNA‑seq data in an integrative and user‑friendly manner

Research Areas: Biochemistry & Molecular ; Biology Biotechnology & Applied ; Microbiology ; Mathematical & Computational BiologyBackground: IsomiRs are miRNA variants that vary in length and/or sequence when compared to their canonical forms. These variants display differences in length and/or sequence, including additions or deletions of one or more nucleotides (nts) at the 5′ and/or 3′ end, internal editings or untemplated 3′ end additions. Most available tools for small RNA-seq data analysis do not allow the identification of isomiRs and often require advanced knowledge of bioinformatics. To overcome this, we have developed IsomiR Window, a platform that supports the systematic identification, quantification and functional exploration of isomiR expression in small RNA-seq datasets, accessible to users with no computational skills. Methods: IsomiR Window enables the discovery of isomiRs and identification of all annotated non-coding RNAs in RNA-seq datasets from animals and plants. It comprises two main components: the IsomiR Window pipeline for data processing; and the IsomiR Window Browser interface. It integrates over ten third-party softwares for the analysis of small-RNA-seq data and holds a new algorithm that allows the detection of all possible types of isomiRs. These include 3′ and 5′end isomiRs, 3′ end tailings, isomiRs with single nucleotide polymorphisms (SNPs) or potential RNA editings, as well as all possible fuzzy combinations. IsomiR Window includes all required databases for analysis and annotation, and is freely distributed as a Linux virtual machine, including all required software. Results: IsomiR Window processes several datasets in an automated manner, without restrictions of input file size. It generates high quality interactive figures and tables which can be exported into different formats. The performance of isomiR detection and quantification was assessed using simulated small-RNA-seq data. For correctly mapped reads, it identified different types of isomiRs with high confidence and 100% accuracy. The analysis of a small RNA-seq data from Basal Cell Carcinomas (BCCs) using isomiR Window confirmed that miR-183-5p is up-regulated in Nodular BCCs, but revealed that this effect was predominantly due to a novel 5′end variant. This variant displays a different seed region motif and 1756 isoform-exclusive mRNA targets that are significantly associated with disease pathways, underscoring the biological relevance of isomiR-focused analysis. IsomiR Window is available at https ://isomi r.fc.ul.pt/.info:eu-repo/semantics/publishedVersio

Sulfated small molecules targeting EBV in Burkitt lymphoma: from in silico screening to the evidence of in vitro effect on viral episomal DNA

Epstein–Barr virus (EBV) infects more than 90% of the world population. Following primary infection, Epstein– Barr virus persists in an asymptomatic latent state. Occasionally, it may switch to lytic infection. Latent EBV infection has been associated with several diseases, such as Burkitt lymphoma (BL). To date, there are no available drugs to target latent EBV, and the existing broad-spec trum antiviral drugs are mainly active against lytic viral infection. Thus, using computational molecular docking, a virtual screen of a library of small molecules, including xanthones and flavonoids (described with potential for antiviral activity against EBV), was carried out targeting EBV proteins. The more interesting molecules were selected for further computational analysis, and sub sequently, the compounds were tested in the Raji (BL) cell line, to evaluate their activity against latent EBV. This work identified three novel sulfated small molecules capable of decreasing EBV levels in a BL. Therefore, the in silico screening presents a good approach for the development of new anti-EBV agents.info:eu-repo/semantics/publishedVersio

Questions in Science textbooks: development and validation of a checklist

Questões são enunciadas que requerem uma resposta refletida e que desempenham diversas funções educativas, incluindo o despoletar novas aprendizagens. Neste caso, o seu uso enquadra-se na Aprendizagem Baseada na Resolução de Problemas (ABRP, do inglês, Problem-Based Learning, PBL), que coloca o aluno no centro dos processos de ensino e aprendizagem, atribuindo-lhe um papel ativo na aprendizagem de novo conhecimento. Atendendo à influência que os manuais exercem nas práticas de ensino, a questão que se coloca é a de saber em que medida as questões incluídas nos manuais escolares de Ciências podem fomentar um ensino orientado para a ABRP. Neste texto, descrever-se-á o processo de construção e validação de uma grelha de análise de questões incluídas em manuais escolares de Ciências com essa finalidade, apresentando-se não só essa grelha, mas também, a título ilustrativo, uma aplicação da mesma a um tópico de Ciências, 8º ano, abordado nas duas disciplinas desta área.Questions require a thoughtful answer and can play diverse educational roles, such as stimulating the learning of new knowledge, as is the case in Problem-Based Learning (PBL) contexts. In this context, the student is placed at the center of the teaching and learning processes and plays an active role in the learning of new knowledge. Bearing in mind the influence that textbooks exert on teaching practices, it is worthwhile questioning to which extent questions included in school science textbooks promote a PBL oriented teaching approach. This paper describes the development and validation of a checklist for analyzing the questions included in science textbooks. After introducing the checklist, an example of its application to a science unit assigned to two junior high school science courses (8th grade) is given, approaching the two disciplines in the area

Active regulatory T-cells contribute to broadened T-cell repertoire diversity in ivIg-treated SLE patients

Octapharma

Forward Neutral Pion Transverse Single Spin Asymmetries in p+p Collisions at \sqrt{s}=200 GeV

We report precision measurements of the Feynman-x dependence, and first measurements of the transverse momentum dependence, of transverse single spin asymmetries for the production of \pi^0 mesons from polarized proton collisions at \sqrt{s}=200 GeV. The x_F dependence of the results is in fair agreement with perturbative QCD model calculations that identify orbital motion of quarks and gluons within the proton as the origin of the spin effects. Results for the p_T dependence at fixed x_F are not consistent with pQCD-based calculations.Comment: 6 pages, 4 figure