Is there a relationship between ferric-chelate reductase activity in roots of poncirus trifoliata and leaf chlorophyll contents?

Poncirus trifoliata is a citrus rootstock very sensitive to Fe deficiency. This deficiency is very common in crops grown in calcareous soils due to the detrimental effect of bicarbonate ion. Higher plants have distinct behaviours when faced with Fe chlorosis, and several mechanisms may be activated under Fe shortage. The aim of this study was to investigate the activity of ferric-chelate reductase (FC-R), a key enzyme in Fe uptake, and to verify whether relationships with leaf chlorophyll contents could be established. Plants were grown in nutrient solutions without Fe (0 μM Fe), with 1 μM Fe, with 120 μM Fe and with 120 μM Fe plus CaCO3 (1 g L-1). Total leaf chlorophyll in young and mature leaves was determined using a calibration model based on a relationship between SPAD readings and concentration of chlorophyll (r2=0.95; P<0.01). The activity of FC-R was determined in roots apexes and several biomass parameters in shoots (number of leaves, height, dry and fresh weight) and roots (dry and fresh weight) were evaluated at the end of the experiment. The activity of FC-R increased in plants grown without iron (0 μM Fe). The results about the relations between root FC-R and leaf chlorophyll are discussed.info:eu-repo/semantics/publishedVersio

Bacterial coaggregation in aquatic systems

The establishment of a sessile community is believed to occur in a sequence of steps where genetically distinct bacteria can become attached to partner cells via specific molecules, in a process known as coaggregation. The presence of bacteria with the ability to autoaggregate and coaggregate has been described for diverse aquatic systems, particularly freshwater, drinking water, wastewater, and marine water. In these aquatic systems, coaggregation already demonstrated a role in the development of complex multispecies sessile communities, including biofilms. While specific molecular aspects on coaggregation in aquatic systems remain to be understood, clear evidence exist on the impact of this mechanism in multispecies biofilm resilience and homeostasis. The identification of bridging bacteria among coaggregating consortia has potential to improve the performance of wastewater treatment plants and/or to contribute for the development of strategies to control undesirable biofilms. This study provides a comprehensive analysis on the occurrence and role of bacterial coaggregation in diverse aquatic systems. The potential of this mechanism in water-related biotechnology is further described, with particular emphasis on the role of bridging bacteria.This work was financially supported by: Base Funding UIDB/00511/2020 of LEPABE and UIDB/00081/2020 of CIQUP funded by national funds through the FCT/MCTES (PIDDAC); Project Biocide_for_Biofilm-PTDC/BII-BTI/30219/2017-POCI-01-0145-FEDER 030219, ABFISH–PTDC/ASP-PES/28397/2017-POCI-01-0145-FEDER 028397 and ALGAVALOR-POCI-01-0247-FEDER-035234, funded by FEDER funds through COMPETE2020–Programa Operacional Com petitividade e Internacionalização (POCI) and by national funds (PIDDAC) through FCT/MCTES. This study was further supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. The authors also thank to CITAB (Centre for the Research and Technology of Agro-Environmental and Biological Sciences) under the scope of the FCT funds with reference UIDB/AGR/04033/2020. Ana Afonso acknowledges the FCT grant 2020.04773.BD.info:eu-repo/semantics/publishedVersio

Expansion of activated cxcr5+icos+ tfh cells and plasmablasts induced by seasonal influenza vaccine is impaired in anti-il-6r treated rheumatoid arthritis patients

Objectives: To investigate the importance of IL-6 for the in vivo differentiation of human Tfh cells, taking advantage of influenza vaccination in patients under anti-IL-6R therapy.info:eu-repo/semantics/publishedVersio

Neurociência e educação: propostas e contribuições para a aprendizagem contemporânea

Com o avanço da neurociência, nos últimos anos, faz-se importante refletir sobre as aplicações em sala de aula e contrapor as interpretações rasas de estudos científicos. Sendo assim, este estudo procura acentuar a interface existente entre neurociência e educação, visando aprimorar o processo de ensino-aprendizagem, sob visões e panoramas interdisciplinares, e, sobretudo, evitar a proliferação dos chamados neuromitos arraigados na educação. O objetivo é promover subsídios para professores e profissionais da área da educação na apropriação de conhecimentos da neurociência a fim de incorporá-los na práxis de sala de aula. O problema norteou-se pelo questionamento de quais contribuições do campo neurocientífico incidem diretamente na prática pedagógica e na aprendizagem. A metodologia deu-se pela revisão de literatura com pesquisa qualitativa de cunho bibliográfico. Dos 88 artigos encontrados por meio das palavras-chave, “neurociência”, “educação” e “sala de aula”, apenas 6 atenderam aos requisitos baseados no objetivo previamente descrito. No que tange subsidiar pesquisas futuras, considerando-se os desafios educacionais atuais, os resultados evidenciam que a interrelação neurociência/educação pode refletir no contexto da sala de aula, contribuir na formação de professores e cientistas mutuamente, no conhecimento do cérebro, na evolução de estratégias e intervenções bem-sucedidas no cotidiano educativo e contextos neurocientíficos

Contribution for new genetic markers of rheumatoid arthritis activity and severity : sequencing of the tumor necrosis factor-alpha gene promoter

© 2007 Fonseca et al.; licensee BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly citedThe objective of this study was to assess whether clinical measures of rheumatoid arthritis activity and severity were influenced by tumor necrosis factor-alpha (TNF-alpha) promoter genotype/haplotype markers. Each patient's disease activity was assessed by the disease activity score using 28 joint counts (DAS28) and functional capacity by the Health Assessment Questionnaire (HAQ) score. Systemic manifestations, radiological damage evaluated by the Sharp/van der Heijde (SvdH) score, disease-modifying anti-rheumatic drug use, joint surgeries, and work disability were also assessed. The promoter region of the TNF-alpha gene, between nucleotides -1,318 and +49, was sequenced using an automated platform. Five hundred fifty-four patients were evaluated and genotyped for 10 single-nucleotide polymorphism (SNP) markers, but 5 of these markers were excluded due to failure to fall within Hardy-Weinberg equilibrium or to monomorphism. Patients with more than 10 years of disease duration (DD) presented significant associations between the -857 SNP and systemic manifestations, as well as joint surgeries. Associations were also found between the -308 SNP and work disability in patients with more than 2 years of DD and radiological damage in patients with less than 10 years of DD. A borderline effect was found between the -238 SNP and HAQ score and radiological damage in patients with 2 to 10 years of DD. An association was also found between haplotypes and the SvdH score for those with more than 10 years of DD. An association was found between some TNF-alpha promoter SNPs and systemic manifestations, radiological progression, HAQ score, work disability, and joint surgeries, particularly in some classes of DD and between haplotypes and radiological progression for those with more than 10 years of DD.This work was supported by grant POCTI/SAU-ESP/59111/2004 from Fundação Ciência e Tecnologia.info:eu-repo/semantics/publishedVersio

Population structure and genetic diversity of Brazilian popcorn germplasm inferred by microsatellite markers

Background: The genetic diversity and structure of 31 popcorn accessions of the germplasm bank of the State University of Maring\ue1 were assessed using 30 microsatellite primers. Results: 127 alleles were identified from 30 evaluated loci. The number of alleles per locus ranged from two to eight. The overall mean of the polymorphic loci averaged 79.89%. The primers UMC1549 and UMC1072 detected polymorphism in all accessions analyzed. The mean observed heterozygosity ranged from 0.07 to 0.30 and the highest proportion of heterozygous plants was observed in accession BOZM 260 (Ho = 0.30). The analysis of molecular variance revealed that 60% of the total genetic variation was found within accessions and 40% was found between accessions. The Bayesian clustering approach grouped the 31 accessions into two genetically differentiated clusters. The dendrogram revealed that accessions TATU 2 and ARZM 05 083 are genetically less similar than the others. Conclusions: The analysis allowed to identify microsatellite lociwith high levels of heterozygosity (UMC1549 and UMC1072). These loci can be indicated as promising for detecting polymorphisms in popcorn accessions and in the monitoring of genetic improvement programs. Moreover, allowed to identify heterozygous accessions (BOZM 260), this accession showed allelic variation at all analyzed microsatellite loci and can be recommended for crosses with plants that have desirable agronomic characteristics, with a view to the broadening of the genetic base of popcorn accessions and developing new cultivars

Efficient second harmonic generation by para-nitroaniline embedded in electro-spun polymeric nanofibres

Intense well polarized second harmonic light was generated by poly(methyl methacrylate) nanofibres with embedded para-nitroaniline nanocrystals. Subwavelength diameter fibres were electro-spun using a 1.2 weight ratio of chromophore to polymer. Analysis of the generated second harmonic light indicates that the para-nitroaniline molecules, which nominally crystalize in the centrosymmetric space group, were organized into noncentrosymmetric structures leading to a second order susceptibility dominated by a single tensor element. Under the best deposition conditions, the nanofibrers display an effective nonlinear optical susceptibility approximately two orders of magnitude greater than that of potassium dihydrogen phosphate. Generalizing this approach to a broad range of organic molecules with strong individual molecular second order nonlinear responses, but which nominally form centrosymmetric organic crystals, could open a new pathway for the fabrication of efficient sub-micron sized second harmonic light generators.Hugo Goncalves thanks the Portuguese Foundation for Science and Technology (FCT) for the support under grant PD/BD/111873/2015. The equipment used to characterize the second harmonic response of the electro-spun fibres was acquired within the framework of the Portuguese National Program for Scientific Re-equipment, contract REEQ-25/FIS/2005 with funds from POCI 2010 (FEDER) and FCT. The Raman microscope was acquired through the project nSTeP Nanostructured Systems for Tailored Performance, NORTE-07-0124-FEDER-000039, ON. 2. This work was in part developed in the scope of the projects CICECO-Aveiro Institute of Materials (UID/CTM/50011/2013), financed by national funds through the Fundacao para a Ciencia e a Tecnologia/Ministerio da Educacao e Ciencia (FCT/MEC) and co-financed by FEDER under the PT2020 Partnership Agreement. The authors are grateful to A M P Botas (University of Aveiro) for help in acquiring the hyperspectral microscopy data.info:eu-repo/semantics/acceptedVersio

Measurement of D∗+/−D^{*+/-} meson production in jets from pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

This paper reports a measurement of D*+/- meson production in jets from proton-proton collisions at a center-of-mass energy of sqrt(s) = 7 TeV at the CERN Large Hadron Collider. The measurement is based on a data sample recorded with the ATLAS detector with an integrated luminosity of 0.30 pb^-1 for jets with transverse momentum between 25 and 70 GeV in the pseudorapidity range |eta| D0pi+, D0 -> K-pi+, and its charge conjugate. The production rate is found to be N(D*+/-)/N(jet) = 0.025 +/- 0.001(stat.) +/- 0.004(syst.) for D*+/- mesons that carry a fraction z of the jet momentum in the range 0.3 < z < 1. Monte Carlo predictions fail to describe the data at small values of z, and this is most marked at low jet transverse momentum.Peer Reviewe

Search for extra dimensions using diphoton events in 7 TeV proton–proton collisions with the ATLAS detector

Using data recorded in 2011 with the ATLAS detector at the Large Hadron Collider, a search for evidence of extra spatial dimensions has been performed through an analysis of the diphoton final state. The analysis uses data corresponding to an integrated luminosity of 2.12 fb^-1 of sqrt(s) = 7 TeV proton-proton collisions. The diphoton invariant mass spectrum is observed to be in good agreement with the expected Standard Model background. In the large extra dimension scenario of Arkani-Hamed, Dimopoulos and Dvali, the results provide 95% CL lower limits on the fundamental Planck scale between 2.27 and 3.53 TeV, depending on the number of extra dimensions and the theoretical formalism used. The results also set 95% CL lower limits on the lightest Randall-Sundrum graviton mass of between 0.79 and 1.85 TeV, for values of the dimensionless coupling k/\bar{M}_{Pl} varying from 0.01 to 0.1. Combining with previously published ATLAS results from the dielectron and dimuon final states, the 95% CL lower limit on the Randall-Sundrum graviton mass for k/\bar{M}_{Pl} = 0.01 (0.1) is 0.80 (1.95) TeV.Peer Reviewe

Search for events with large missing transverse momentum, jets, and at least two tau leptons in 7 TeV proton–proton collision data with the ATLAS detector

A search for events with large missing transverse momentum, jets, and at least two tau leptons has been performed using 2 fb^-1 of proton-proton collision data at sqrt(s) = 7 TeV recorded with the ATLAS detector at the Large Hadron Collider. No excess above the Standard Model background expectation is observed and a 95% CL visible cross section upper limit for new phenomena is set. A 95% CL lower limit of 32 TeV is set on the GMSB breaking scale Lambda independent of tan(beta). These limits provide the most stringent tests to date in a large part of the considered parameter space.Peer Reviewe