Pattern avoidance in forests of binary shrubs

We investigate pattern avoidance in permutations satisfying some additional restrictions. These are naturally considered in terms of avoiding patterns in linear extensions of certain forest-like partially ordered sets, which we call binary shrub forests. In this context, we enumerate forests avoiding patterns of length three. In four of the five non-equivalent cases, we present explicit enumerations by exhibiting bijections with certain lattice paths bounded above by the line y = lx, for some l in Q+, one of these being the celebrated Duchon’s club paths with l = 2/3. In the remaining case, we use the machinery of analytic combinatorics to determine the minimal polynomial of its generating function, and deduce its growth rate

Blockade of chemokine-induced signalling inhibits CCR5-dependent HIV infection in vitro without blocking gp120/CCR5 interaction.

BACKGROUND: Cellular infection with human immunodeficiency virus (HIV) both in vitro and in vivo requires a member of the chemokine receptor family to act as a co-receptor for viral entry. However, it is presently unclear to what extent the interaction of HIV proteins with chemokine receptors generates intracellular signals that are important for productive infection. RESULTS: In this study we have used a recently described family of chemokine inhibitors, termed BSCIs, which specifically block chemokine-induced chemotaxis without affecting chemokine ligands binding to their receptors. The BSCI termed Peptide 3 strongly inhibited CCR5 mediated HIV infection of THP-1 cells (83 +/- 7% inhibition assayed by immunofluoresence staining), but had no effect on gp120 binding to CCR5. Peptide 3 did not affect CXCR4-dependent infection of Jurkat T cells. CONCLUSION: These observations suggest that, in some cases, intracellular signals generated by the chemokine coreceptor may be required for a productive HIV infection

Biological interactions between nematophagous fungi, Esteya spp., and the pinewood nematode, Bursaphelenchus xylophilus

The pinewood nematode (PWN), Bursaphelenchus xylophilus, is a quarantine organism in several countries and the causal agent of pine wilt disease (PWD), a serious threat to pine forests worldwide. PWD results from complex interactions between the nematode, its insect vector, Monochamus spp., and host plants (conifers), being the nematode the common element in this interaction. The PWN is considered the sixth most economically important plant-parasitic nematode. In Europe, this pest was first reported in Portugal in 1999, in maritime pine, Pinus pinaster. Due to its economic importance and worldwide distribution, an enormous amount of effort is devoted to research on B. xylophilus and PWD. Scenarios strongly suggest that climate change is likely going to cause a spread of PWD and outbreaks in areas free of the disease. The urgent need for sustainable management strategies has led to an increasing interest in antagonists capable of suppressing the PWN. Nematophagous fungi belonging to the Esteya genus are reported as natural enemies of the PWN and promising biocontrol agents. There are currently two described species: E. vermicola and E. floridanum, the first of which is capable of mimicking volatile organic compounds produced naturally by Pinus spp. in order to attract PWN. However, few studies have been carried out on the development of Esteya spp. inside pine trees, and none using maritime pine, the main and most affected species in Portuguese forests and its largest carbon reservoir. It is therefore crucial to understand the plant-nematode-fungus interactions between P. pinaster, B. xylophilus and Esteya spp. In this sense, biological interactions between these two antagonists, the PWN and P. pinaster were investigated, namely fungus-fungus, fungus-nematode and fungus-tree, as well as feeding trials and chemotaxis assays, to determine the attractive power of both fungal species. These results will enlighten us on the most promising species for biocontrol and help us devise new ways to manage PWD

Amylase polymorphism in Drosophila melanogaster: haplotype frequencies in tropical African and American populations

International audienc

Perceptions on mobile information among undergraduates before and after Covid-19: Some comparisons

A comparative analysis of Social Sciences undergraduates’ perceptions of information literacy (IL) and the use/inclusion of mobile technologies (MT) at the universities of Granada (Spain) and ISPA (Lisboa) before and after the Covid-19 pandemics. An exploratory socio-constructive focus group methodology was carried out based on a sample of eighteen Psychology and Education undergraduates, in the final year of their studies (May 2022). We implemented two focus groups, one in each country. Undergraduates experienced significant gaps, especially in IL knowledge and MT skills. They also perceived attitudinal and technological limitations in their teachers. Morever, there are some differences in attitudes towards MT inclusion in the processes of teaching and learning, according to the context. In this regard, Spanish undergraduates showed better skills and Portuguese ones a higher level of selfperception. Some shortages derived from the Covid-19 pandemic emerge, since there is a growing body of evidence on both the need for student-teacher closeness and the technical limitations of some teacher. After this critical situation, an open-to-experience mentality on the part of all the stakeholders is necessary. Due to the qualitative methodology, we have implemented, the research is limited to a specific sector to be analyzed (Social Sciences undergraduates belonging to the last pregraduate year). Academic, educational institutions and teachers (responsible for the training of future generations) must strive to understand the scope of mobile teaching and the possibilities of mobile devices to increase student’s motivations and to acquire basic skills too. To reflect on this situation turns into a priority to optimize the teaching-learning processes.Resumén: Análisis comparativo de las percepciones sobre la alfabetización informacional (Alfin) y el uso/inclusión de tecnologías móviles (MT) de los estudiantes de pregrado de Ciencias Sociales en las universidades de Granada (España) y ISPA (Lisboa) antes y después de la pandemia de Covid-19. Se siguió exploratoria socioconstructivista basada en grupos focales (mayo de 2022) con una muestra de dieciocho estudiantes de Psicología y Educación, en el último año de sus estudios. Se implementaron dos grupos focales, uno en cada país. El estudiantado de pregrado experimenta brechas significativas, especialmente en el conocimiento de la Alfin y las habilidades en MT. También perciben limitaciones actitudinales y tecnológicas en sus profesores. Además, existen diferencias en las actitudes hacia la inclusión de MT en los procesos de enseñanza y aprendizaje, según el contexto. En este sentido, los estudiantes españoles mostraron mejores habilidades y los portugueses un mayor nivel de autopercepción. Surgen algunas carencias derivadas de la pandemia de Covid-19, ya que hay un creciente cuerpo de evidencia sobre la necesidad de proximidad estudiante-profesor y las limitaciones técnicas de algunos profesores. Después de esta situación crítica, es necesaria una mentalidad abierta a la experiencia por parte de todos los interesados. Debido a la metodología cualitativa implementada, la investigación se limita a un sector específico para ser analizado (estudiantes de Ciencias Sociales pertenecientes al último año de pregrado). Las instituciones académicas, educativas y el profesorado (responsable de la formación de las futuras generaciones) deben esforzarse por comprender el alcance de la enseñanza móvil y las posibilidades de los dispositivos móviles para aumentar la motivación de los estudiantes y adquirir habilidades básicas también. Reflexionar sobre esta situación se convierte en una prioridad para optimizar los procesos de enseñanza-aprendizaje.info:eu-repo/semantics/acceptedVersio

Global change effects on plant communities are magnified by time and the number of global change factors imposed

Global change drivers (GCDs) are expected to alter community structure and consequently, the services that ecosystems provide. Yet, few experimental investigations have examined effects of GCDs on plant community structure across multiple ecosystem types, and those that do exist present conflicting patterns. In an unprecedented global synthesis of over 100 experiments that manipulated factors linked to GCDs, we show that herbaceous plant community responses depend on experimental manipulation length and number of factors manipulated. We found that plant communities are fairly resistant to experimentally manipulated GCDs in the short term (\u3c 10 y). In contrast, long-term (\u3e= 10 y) experiments show increasing community divergence of treatments from control conditions. Surprisingly, these community responses occurred with similar frequency across the GCD types manipulated in our database. However, community responses were more common when 3 or more GCDs were simultaneously manipulated, suggesting the emergence of additive or synergistic effects of multiple drivers, particularly over long time periods. In half of the cases, GCD manipulations caused a difference in community composition without a corresponding species richness difference, indicating that species reordering or replacement is an important mechanism of community responses to GCDs and should be given greater consideration when examining consequences of GCDs for the biodiversity-ecosystem function relationship. Human activities are currently driving unparalleled global changes worldwide. Our analyses provide the most comprehensive evidence to date that these human activities may have widespread impacts on plant community composition globally, which will increase in frequency over time and be greater in areas where communities face multiple GCDs simultaneously

Who the hell was that? Stories, bodies and actions in the world

This article explores a two-way relationship between stories and the experiential actions of bodies in the world. Through an autoethnographic approach, the article presents a series of interlinked story fragments in an effort to show and evoke a feel for the ways in which stories, bodies, and actions influence and shape each other over time. It offers some reflections on the experiences the stories portray from the perspective of a social constructionist conception of narrative theory and suggest that while stories exert a powerful influence on the actions of our bodies, our bodies intrude on or ‘talk back’ to this process because bodies have an existence beyond stories

Reduced salivary flow and colonization by mutans streptococci in children with Down syndrome

OBJECTIVES: Although individuals with Down syndrome have considerable oral disease, the prevalence of dental caries in this group is low. The present study aimed to compare known risk factors for dental caries development in children with Down syndrome and a matched population (siblings). In both populations, the number of acidogenic microorganisms, such as mutans streptococci, lactobacilli and Candida species, and the paraffin-stimulated pH, flow rate and IgA concentration in whole saliva were evaluated and compared. METHOD: Saliva was collected, and the caries index was evaluated in 45 sibling pairs aged between 6 and 18 years old. The salivary IgA concentration was determined by immunoturbidimetry. Salivary mutans streptococci, lactobacilli and Candida species were quantified on mitis salivarius agar containing bacitracin and 20% sucrose, rogosa agar supplemented with glacial acetic acid and sabouraud agar supplemented with chloramphenicol, respectively. RESULTS: Down syndrome children had a higher caries-free rate (p<0.05) and lower salivary mutans streptococci counts (p<0.03) compared to their siblings. Similar numbers of lactobacilli and Candida species were found in both groups. Salivary flow rates were 36% lower in Down syndrome children compared to their siblings (p<0.05). The salivary pH did not differ between Down syndrome children and controls. The Down syndrome children had an IgA secretion rate 29% lower than that of their siblings, but this difference was not statistically significant. CONCLUSIONS: In conclusion, the lower number of mutans streptococci in the saliva may be one of the factors contributing to the lower caries rate observed in Down syndrome children, despite evidence of hyposalivation