A case study of molinate application in a Portuguese rice field: herbicide dissipation and proposal of a clean-up methodology

This study was designed to monitor molinate losses in surface and underground waters during Ordram application in a rice field situated in central Portugal. Water samples were collected from different sites, before, during and about one month and a half after Ordram application. Molinate quantification was based on a solid-phase microextraction (SPME) method followed by gas chromatography with flame photometric detector (GC–FPD) analysis, and led to the conclusion that the herbicide was dissipated in the environment, reaching levels as high as 3.9 lg l⁻¹ in underground water and 15.8 lg l⁻¹ in the river receiving tail waters. The feasibility of the application of treatment methodologies based on adsorption or biodegradation as processes to remove molinate from real-world waters was assessed. These methods seem suitable to reduce molinate concentrations to values in the range of the legally recommended limits (<0.5 lg l⁻¹)

Diversity of bacterial isolates from commercial and homemade composts

The diversity of heterotrophic bacterial isolates of three commercial and two homemade composts was studied. The commercial composts were produced from poultry litter (PC), sewage sludge (SC), municipal solid waste (MC), and homemade composts (thermal compost [DC] and vermicompost [VC]) from food wastes. The taxonomic and physiological diversity of the heterotrophic culturable bacteria was assessed using phenotypic and genotypic characterization and the analysis of the partial 16S rRNA gene sequence. Composts DC and SC presented the higher genotypic diversity, as could be inferred from the number of distinct genotypic patterns observed, 28 and 21, respectively. Gram-positive bacteria, mainly Firmicutes, were predominant in all the composts. Some organisms related with taxa rarely reported in composts, as Rhodanobacter spathiphylli, Moraxella osloensis, Lysobacter, Corynebacterium, Pigmentiphaga kullae, and new taxa were also isolated. The highest relative proportion of isolates able to degrade starch was found in compost SC (>70%), to degrade gelatine in compost DC (>70%), to degrade Tween 80 in compost PC (>90%), and to degrade poly-epsilon-caprolactones in compost DC (>80%). Compost MC presented the lowest relative proportions of isolates able to degrade starch (<25%), gelatine (<20%), and poly-epsilon-caprolactone (<40%). When compared with the others, the homemade composts presented higher relative proportions of Gram-positive isolates able to inhibit the target organisms Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, or Pseudomonas aeruginosa. In compost MC, none of the Gram-positive isolates was able to inhibit those targets

Preliminary feasibility study for the use of an adsorption/bio-regeneration system for molinate removal from effluents

This work studies the feasibility of the use of a combined physical-biological remediation procedure for treatment of effluents contaminated with molinate, where the herbicide is removed through adsorption and biodegraded in a subsequent stage, with the regeneration of the adsorbent. In order to select the most adequate absorbent for molinate, different materials were tested, namely pine bark, activated carbon and resin Amberlite XAD-4. Activated carbon and resin Amberlite XAD-4 were the most efficient on the removal of molinate from solutions, although the activated carbon used proved not to be bio-regenerable. It was also observed that factors such as temperature, pH, and conductivity did not affect significantly molinate adsorption onto resin Amberlite XAD-4. Resin Amberlite XAD-4 was successfully bio-regenerated, being observed that biodegradation was mainly dependent on spontaneous desorption of the molinate. After bio-regeneration, the resin could be re-utilised as adsorbent

Uma visão sistêmica do processo criador

A abordagem sistêmica faz uma leitura do mundo distinta  da abordagem mecanicista, sem negá-la completamente, mas ampliando a sua perspectiva para dar um novo entendimento a fenômenos até então sem resposta. Um tipo de abordagem sistêmica bem conhecido é o sistêmico-cibernético, que foi descrito em dois momentos. Um de          primeira ordem, que enfatiza o padrão e estabilidade, define o mundo como algo a ser descoberto, um sistema em busca do equilíbrio. O outro, de segunda ordem, estuda os sistemas fora do equilíbrio, no qual a aparente desordem é apenas momentânea,  uma vez que se acredita que existe sempre uma organização ou padrão subjacente. Fazendo uma analogia entre o modelo sistêmico-cibernético e a dinâmica do       processo criador, entende-se que o artista como um transgressor do       status quo, frequentemente  desequilibra o sistema, gerando sempre a busca de um novo equilíbrio. Quanto aos seus manuscritos, eles compõem um sistema governado por leis próprias, que traduzem o estilo docriador. Como esses documentosde processo e seu criador sãovistos dentro dos modelos sistêmicos cibernéticos é um tema  que merece reflexão

Comfort parameters and particulate matter (PM10 and PM2.5) in school classrooms and outdoor air

In January 2012, one kindergarten and eight elementary school classrooms were monitored. The campaign included simultaneous measurements, indoors and outdoors, of comfort parameters, CO, CO2 and particles. Automatic monitors using a light scattering technique were employed to measure PM10 continuously. During occupied periods, low volume samplers were used to daily collect PM2.5 samples, which were subsequently analysed for carbonates, organic carbon (OC), elemental carbon (EC) and water soluble inorganic ions. With regard to comfort, the schools did not meet the recommended levels in many rooms. Indoor-outdoor CO2 ratios between 3 and 12, and indoor levels much higher than 1000 ppm during the occupied periods, indicate the highly inadequate ventilation in these locations. The results clearly demonstrate that there is a high level of exposure to particulate matter in these schools. The continuous measurements of PM10 suggest that the physical activity of pupils, which is assumed to be more marked in younger children, contributes to a constant process of resuspension of sedimented particles. In addition, peak PM10 concentrations coincident with cleaning activities suggest the need to change certain practices to improve cleanliness. Around 40% of the PM2.5 mass is composed of carbonaceous matter, with 4-5 times higher OC mass fractions than EC. It was observed that both OC and EC were significantly influenced by indoor sources. Water-soluble inorganic ions represented around 10-20% of the PM2.5 mass measured in classrooms. Excluding calcium, in general the ionic species were present at indoor-outdoor ratios of less than 1, suggesting the major origin in the outdoor air

The rural school’s curriculum and its connections with the principles of Countryside Education

This article presents the result of a Master's in Education research on the movement of building the curriculum of the Rural Capoeira dos Dinos school, in the municipality of Piraquara/PR from the protagonism of the school's teachers. It seeks to examine how this school and the educators, in their pedagogical work, approach the principles of Countryside Education and how these principles shape the school curriculum. For this purpose, qualitative research was used, which articulated the participation and listening of the rural schoolteachers. The documentary analysis of three curricular proposals and the oral history methodology were adopted as instruments for data collection. Contributions from Arroyo (2007, 2010, 2015); Freire (2002); Schwendler (2010, 2017); Souza (2008, 2016); Sacristán (2000, 2011); Beirnstein (1996); Caldart (2010, 2012) were essential for the debate on the prescribed and recontextualized curriculum and the Countryside Education. The data indicate that the school’s curriculum proposal does not differ from the prescribed curriculum of the municipal network. However, the curriculum in action reveals attempts to prioritize content and strategies that address the specificities of the rural community, in teaching work, based on the process of curricular recontextualization. The results show the possibilities of reinterpreting and reworking the curriculum text, based on the paradigm of Countryside Education, concluding that the participation of teachers and the rural community is fundamental in the construction of the curriculum. The school in the countryside is advocated as a space for reconstruction, dialogue, and transformation, generating the construction of a curriculum that reflects the needs of the communities

Estimation and incommutativity in mixed models

In this paper we present a treatment for the estimation of variance components and estimable vectors in linear mixed models in which the relation matrices may not commute. To overcome this difficulty, we partition the mixed model in sub-models using orthogonal matrices. In addition, we obtain confidence regions and derive tests of hypothesis for the variance components. A numerical example is included. There we illustrate the estimation of the variance components using our treatment and compare the obtained estimates with the ones obtained by the ANOVA method. Besides this, we also present the restricted and unrestricted maximum likelihood estimates.info:eu-repo/semantics/publishedVersio

Olhares femininos sobre a praxe académica

VII Congresso Internacional A Vez e a Voz das Mulheres Migrantes em Portugal e na Diáspora: Mobilidades, Tempos e Espaços. Porto, 11 a 13 de junho de 2015 (Comunicação).A praxe académica tem estado sob a mira dos gestores das instituições de ensino superior, sendo apontada como causadora de danos severos na vida do estudante recém-chegado. A investigação apresenta dados controversos. Por um lado, dá a conhecer casos em que veteranos e caloiros afirmam as atividades da praxe promotoras da integração dos recém-chegados e da convivência entre estudantes. Por outro lado, dá a conhecer casos que corroboraram a ideia de práticas deliberadas do exercício da desigualdade de poderes. Esta última perspetiva surge mais entre o sexo feminino, situação que assume particular acuidade numa sociedade onde a violência de género ainda é um fenómeno marcante. O presente estudo visa contribuir para a compreensão desses acontecimentos iniciáticos na ótica de género. Comparam-se perceções sobre a relação com a praxe em estudantes do sexo masculino e feminino de uma instituição de ensino superior português. Participaram no estudo 247 estudantes, 91 do sexo masculino e 156 do sexo feminino, a frequentar o 1º Ciclo de Estudos. Os dados foram recolhidos através da escala de “Avaliação das situações de Bullying nas Praxes do Ensino Superior”, composta por 15 itens organizados em três dimensões: Relação Positiva com a Praxe, Relação Negativa com a Praxe e Dimensão Social. Os resultados obtidos com recurso a um conjunto de técnicas estatísticas apropriadas informam que na escala global existem diferenças significativas (U=4683.50; p=0.042< α=0.05) entre rapazes (mm=120.57) e raparigas (mf=102.69), com os rapazes a evidenciarem melhor relação com a praxe. Na análise por dimensões este dado é robustecido, pois os rapazes apresentam resultados significativamente mais elevados do que as raparigas na Relação Positiva com a Praxe (mm=126.88; mf=98.35; U= 4060; p=0.001 < α=0.05). Nas outras duas dimensões as diferenças observadas não têm significância estatística. Estes resultados parecem chamar a atenção para a importância do acolhimento, integração e socialização das estudantes, cuja tonalidade ainda aparece como menos positiva.N/

Estudo da resistência de Pneumocystis jirovecii ao cotrimoxazol em doentes com infecção VIH SIDA

Pneumocystis jirovecii é um eucariota responsável por um quadro clínico de pneumonia intersticial grave em indivíduos imunocomprometidos. Apesar do decréscimo da incidência da pneumonia por P. jirovecii (PPc) como resultado da introdução da profilaxia específica e da terapêutica antirretroviral potente (HAART, do inglês “Highly active antiretroviral therapy”), esta doença continua a ser uma das infecções oportunistas mais frequentes em doentes com infecção vírus da imunodeficiência humana/síndroma de imunodeficiência adquirida (VIH/SIDA) e com outras imunodeficiências. Os fármacos da família das sulfas, em especial o cotrimoxazol, uma combinação de sulfametoxazol e de trimetoprim, são considerados os agentes de primeira linha na profilaxia e no tratamento desta infecção. Ao longo dos últimos anos, tem sido estudada a variabilidade genética da dihidropteroato sintetase (DHPS) e da dihidrofolato reductase (DHFR), duas enzimas alvo do cotrimoxazol, de P. jirovecii com o intuito de avaliar o possível desenvolvimento de resistência a este fármaco. Por outro lado, o estudo de outros marcadores genéticos, como as regiões dos espaçadores internos transcritos (ITS, do inglês "Internal Transcribed Spacers"), em conjunto com o DHPS e o DHFR, tem sido utilizado no sentido de melhor compreender os mecanismos de desenvolvimento de resistência ao cotrimoxazol. Com o presente estudo, pretendeu-se efectuar a caracterização genética da DHPS, da DHFR e das regiões ITS de P. jirovecii, em isolados obtidos entre 1995 e 2004, em doentes imunocomprometidos. Também foi objectivo deste trabalho, estudar a relação dosgenótipos identificados nas três regiões genómicas em análise, entre si e com diversas variáveis clínicas e epidemiológicas. Entre os 403 isolados de P. jirovecii, obtidos entre 2001 e 2004, a percentagem de infecção por P. jirovecii observada foi de 64,5%. No total, 290 isolados de P. jirovecii identificados no período de 2001–2004 (260 isolados) e entre 1995–2000 (30 isolados), foram submetidos ao estudo de caracterização genética, nos três loci em estudo. Inicialmente, com o intuito de melhorar a técnica de amplificação do gene da DHPS de P. jirovecii, procedeu-se á filtração das amostras de secreções pulmonares, para remoção de DNA do hospedeiro contaminante, e foi elaborado um novo protocolo de amplificação. Apesar, de se ter verificado que o processo de microfiltração não promovia uma melhor amplificação de DNA específico de Pneumocystis, o protocolo de PCR “nested” desenhado contribuiu para a maior amplificação do gene da DHPS de P. jirovecii (P <0,001). A caracterização genética da DHPS e da DHFR, permitiu identificar o genótipo selvagem em 84,5% e 68,9%, respectivamente, dos isolados estudados. Em 15,5% dos isolados, observou-se a presença de genótipos mutantes nos codões 55 e 57 do gene da DHPS. Em relação ao gene da DHFR, 31,1% dos isolados apresentaram polimorfismos. No total, foram identificados nove locais de substituição: quatro substituições sinónimas, nas posições nucleotídicas 201, 272, 312 e 381; cinco substituições nucleotídicas não sinónimas nas posições 38, 68, 92, 154 e 200 que resultaram na alteração nos codões 13, 23, 31, 52 e 67, respectivamente. No estudo efectuado, verificou-se que as mutações do gene da DHPS, foram mais frequentes entre os isolados obtidos em 1995-2000 do que entre os isolados recolhidos entre 2001 e 2004 (P=0,056). Relativamente ao gene da DHFR e, em contraste com a maioria dos estudos publicados, observou-se uma elevada diversidade genética entre os isolados estudados.Também, nas regiões ITS de P. jirovecii, foi observada uma elevada variabilidade entre os isolados estudados. No presente trabalho, 30 genótipos diferentes foram identificados, o que evidencia o elevado grau de diversidade genética destas regiões e a sua utilidade no estudo da transmissão e da epidemiologia da PPc. No estudo efectuado, os genótipos mais frequentes foram o Eg, o Cg e o Gg. Verificou-se que o genótipo Ne foi significativamente mais frequente entre 1995–2000 (P= 0,026) enquanto que o genótipo Eg foi mais frequente entre 2001–2004 (P=0,011). Considerando a combinação dos genótipos identificados nestas três regiões genómicas, foram observados 50 haplótipos distintos em 100 isolados de P. jirovecii. A elevada diversidade intra-específica observada neste estudo multilocus demonstra o potencial que esta abordagem pode ter na diferenciação de tipos P. jirovecii distintos e a sua utilidade no estudo da transmissão e da epidemiologia da PPc. No estudo efectuado, polimorfismos nos genes da DHPS e da DHFR, presumidamente associados à exposição ao cotrimoxazol, foram detectados em doentes não expostos a este fármaco. Esta observação pode sugerir que estas sequências polimórficas possam ser adquiridos acidentalmente, por transmissão pessoa-a-pessoa ou através de uma fonte ambiental, e não somente por pressão selectiva do cotrimoxazol. Também, a identificação de genótipos idênticos, nas três regiões genómicas em estudo, em diferentes populações de doentes sugere a ocorrência de transmissão pessoa-a-pessoa. No geral, o presente trabalho contribuiu para a clarificação do papel das mutações nos genes da DHPS e da DHFR no possível desenvolvimento de resistência ao cotrimoxazol em P. jirovecii assim como para a melhor compreensão da transmissão e da epidemiologia da PPc.Pneumocystis jirovecii is an eukaryote that causes severe interstitial penumonia in immunocompromised patients. Although the widespread use of P. jirovecii pneumonia (PcP) chemoprophylaxis and highly active antiretroviral therapy (HAART), has reduced the incidence of this infection it remains an important opportunistic infection in acquired immunodeficiency syndrome (AIDS) and other immunocompromised patients. Sulpha drugs, in particular cotrimoxazole, the fixed combination of sulphamethoxazole and trimethoprim, are key agents for treatment and prophylaxis of PcP. Over the last years, the genetic variability of P. jirovecii dihydropteroate synthase (DHPS) and dihydrofolate reductase (DHFR), the enzimatic targets of cotrimoxazole, has been evaluated in order to assess the potential development of resistance to this drug. Also, the study of other genetic markers, like the internal transcribed spacers (ITS) of the nuclear rRNA, together with the DHPS and DHFR genes, has been used in order to improve the knowledge on the mechanisms involved in the development of cotrimoxazole resistance in P. jirovecii. In the present study, the main objective was to perform the genetic characterization of DHPS, DHFR and ITS regions of P. jirovecii isolates obtained between 1995 and 2004, from immunocompromised patients. Also, we intended to study the association between the genotypes identified at the three genomic regions and with several epidemiological and clinical characteristics. Overall, among the 430 P. jirovecii isolates obtained between 2001 and 2004, the frequence of P. jirovecii infection was 64,5%. Overall, 290 P. jirovecii isolates, obtained inthe time periods 1995–2000 (30) and 2001–2004 (260), were submitted to the multilocus molecular characterization study. Initially, in order to improve the amplification method of the DHPS gene, a microfiltration procedure, for the removal of human cell contamination, and a new PCR method, for amplification in specimens with low parasite load, were evaluated. Although, the microfiltration procedure did not promote the amplification of P. jirovecii specific DNA, a higher amplification rate of DHPS gene was obtained with the “nested” PCR method designed (P < 0,001). In the present work, the genetic characterization of P. jirovecii DHPS and DHFR identified the wiltype genotype in 84,5% and 68,8%, respectively, of the isolates studied. In 15,5% of the isolates, the mutant genotypes at codons 55 and 57 of the DHPS gene was observed. In the DHFR gene, 31,1% of the isolates presented polymorphic sequences with a total of nine substitution sites identified. Four synonymous substitutions, at nucleotide positions 201, 272, 312 and 381 were observed. Also, five nonsynonymous substitutions at nucleotide positions 38, 68, 92, 154 and 200, that lead to amino acid alterations at codons 13, 23, 31, 52 and 67, respectively, were detected. In this study, DHPS mutant sequences were more frequent among the isolates collected between 1995 and 2000, compared with the isolates collected in the time period 2001–2004 (P=0,056). In the DHFR gene, a high genetic diversity was observed in the isolates studied, in contrast with other reports. Also, in the P. jirovecii ITS regions, a high genetic heterogeneity was detected in the studied isolates. In the present work, 30 different genotypes were identified, which demonstrates the high genetic diversity at this locus and confirms their great utility in the study of PcP epidemiology and transmission. In this study, the most frequent genotypeswere Eg, Cg and Gg. Genotype Ne was significantly more frequent between 1995 and 2000 (P=0,026) while type Eg was more frequent in the time period 2001–2004 (P=0,011). Combining the sequences identified at these three genomic regions, 50 different haplotypes were observed among 100 P. jirovecii isolates. The great intra-specific genetic diversity observed in the multilocus study demonstrates the potential of this analysis to distinguish different types of P. jirovecii and its utility in the study of PcP epidemiology and transmission. In the present study, DHPS and DHFR polymorphisms, presumably selected by cotrimoxazole pressure, were detected in imunocompromised patients not exposed to this drug. This observation may suggest that these polymorphic sequences may be incidentally acquired, by person-to person transmission or from an environmental source, and not only by drug selective pressure. Also, the observation of common genotypes, identified at the three genomic regions studied, present in different patients’ populations, suggests the occurrence of person-to-person transmission. Overall, the present work contributed to the clarification of the role of polymorphic sequences of the DHPS and DHFR in the potential development of P. jirovecii cotrimoxazole resistance and in the improvement of PcP epidemiology and transmission

Epidemiology and genetic diversity of invasive Neisseria meningitidis strains circulating in Portugal from 2003 to 2020

Invasive meningococcal disease (IMD) continues to be a public health problem due to its epidemic potential, affecting mostly children. We aimed to present a detailed description of the epidemiology of IMD in Portugal, including insights into the genetic diversity of Neisseria meningitidis strains. Epidemiological analysis included data from the Portuguese National Reference Laboratory of Neisseria meningitidis during 2003 to 2020. Since 2012, N. meningitidis isolates have also been assessed for their susceptibility to antibiotics and were characterized by whole genome sequencing. During 2003–2020, 1392 confirmed cases of IMD were analyzed. A decrease in the annual incidence rate was observed, ranging from 1.99 (2003) to 0.39 (2020), with an average case fatality rate of 7.1%. Serogroup B was the most frequent (69.7%), followed by serogroups C (9.7%), Y (5.7%), and W (2.6%). Genomic characterization of 329 isolates identified 20 clonal complexes (cc), with the most prevalent belonging to serogroup B cc41/44 (26.3%) and cc213 (16.3%). Isolates belonging to cc11 were predominantly from serogroups W (77.3%) and C (76.5%), whereas cc23 was dominant from serogroup Y (65.7%). Over the past 4 years (2017–2020), we observed an increasing trend of cases assigned to cc213, cc32, and cc11. Regarding antimicrobial susceptibility, all isolates were susceptible to ceftriaxone and 61.8% were penicillin-nonsusceptible, whereas 1.4% and 1.0% were resistant to ciprofloxacin and rifampicin. This is the first detailed study on the epidemiology and genomics of invasive N. meningitidis infections in Portugal, providing relevant data to public health policy makers for a more effective control of this disease.info:eu-repo/semantics/publishedVersio