338 research outputs found

    Valorization of water treatment sludge for applications in the construction industry: a review

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    To address the growing global water demand, it is imperative to implement advanced treatment systems and sustainable alternatives for managing the large amount of waste generated during the water purification process, known as water treatment sludge (WTS). Worldwide, researchers and companies are exploring alternatives and methods for the valorization of WTS as a raw material in other processes. It is urgent that all productive sectors, which contribute significantly to greenhouse gas emissions, adopt this management principle to ensure more sustainable production, contributing to the global goal of climate neutrality. Notably, in civil construction, incorporating WTS as a supplementary cementitious material (SCM) shows great promise, considering that the industrial waste currently used for this purpose is increasingly restricted. The use of WTS as a raw material in the cement industry not only contributes to the reduction of the carbon footprint, but also reduces the high waste load still disposed of in landfills. The emerging applications for WTP sludge are reviewed, with emphasis on its valorization in the civil construction as an SCM. The main characteristics of this waste and their impacts on the environment are also addressed.Scientific and Technological Cooperation Protocol between Águas do Norte S.A. and the University ofMinho, within the scope of the Archimedes Doctoral Scholarship

    BIOLOGICAL INVASION OF Corythucha ciliata IN GREEN URBAN SPACES IN PORTUGAL: A NICHE MODELING APPROACH USING MAXIMUM ENTROPY

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    Corythucha ciliata (Hemiptera: Tingidae) \ue9 um inseto nativo da Am\ue9rica do Norte que foi introduzido na Europa, pela It\ue1lia, em 1964. Desde ent\ue3o tem se expandido por toda a Europa, desconhecendo-se a data de chegada e a sua \ue1rea de distribui\ue7\ue3o em Portugal. Esta importante praga invasora alimenta-se na face inferior das folhas de pl\ue1tano, uma das mais importantes \ue1rvores ornamentais nos espa\ue7os verdes urbanos em Portugal, causando senesc\ueancia prematura e eventualmente morte, em casos de infesta\ue7\uf5es severas consecutivas. A modela\ue7\ue3o de nicho est\ue1 se tornando uma ferramenta cada vez mais importante na gest\ue3o de invas\uf5es biol\uf3gicas, tanto antes como depois da introdu\ue7\ue3o do organismo invasor. Neste estudo, o software MaxEnt (m\ue1xima entropia) foi usado na modela\ue7\ue3o da distribui\ue7\ue3o invasiva potencial de Corythucha ciliata em Portugal, a partir de um conjunto de vari\ue1veis ambientais e de dados de presen\ue7a do inseto, obtidos a partir da observa\ue7\ue3o de folhas de pl\ue1tanos amostrados por todo o pa\ueds. De acordo com o melhor modelo gerado pelo MaxEnt, as \ue1reas de maior adequabilidade potencial \ue0 invas\ue3o de Corythucha ciliata encontram-se no norte de Portugal apresentando o sul e as regi\uf5es de maior altitude do norte e centro adequabilidade reduzida ou nula. Observa\ue7\uf5es laboratoriais da biologia de Corythucha ciliata aliadas aos registos de aus\ueancia em v\ue1rias localidades do sul de Portugal e ocorr\ueancia predominante na metade norte de Espanha suportam o modelo desenvolvido. Por\ue9m, a valida\ue7\ue3o do modelo requer futuras prospec\ue7\uf5es nas \ue1reas de reduzida adequabilidade e onde a praga se encontrava virtualmente ausente no momento em que foi realizada a amostragem. Os modelos de adequabilidade podem ser usados como ferramenta auxiliar na tomada de decis\ue3o no que concerne \ue0 gest\ue3o dos espa\ue7os verdes.Corythucha ciliata (Hemiptera: Tingidae) is an insect native to North America which has been introduced into Europe, through Italy, in 1964. Since then it has expanded across Europe being its date of arrival and distributional range in Portugal unknown. This important invasive pest feeds on the underside of the leaves of sycamore trees, one of the most widespread ornamental tree in urban areas of Portugal, causing their premature senescence and eventually death, in case of consecutive severe infestations. Habitat modeling is becoming an increasingly important tool for managing biological invasions, either prior or after the introduction of the invasive organism. In this study the software MaxEnt (maximum entropy) was used to model the distribution of Corythucha ciliata in its Portuguese invasive range, from a set of environmental variables and georeferenced occurrence data obtained from observation of Platanus spp. leaves sampled all over the country. According to the best model developed, the areas of greater suitability to invasion of Corythucha ciliata are located in the northern portion of the country whereas the more southern and mountainous areas are of low or virtually null suitability. Laboratory observations of Corythucha ciliata biology allied to records of pest absence across several localities of southern Portugal and predominant occurrence in the northern half of Spain support the model developed. However, model validation requires future prospection in the areas of predicted reduced suitability and where the pest was virtually absent at the moment of sampling. Suitability models can be a useful tool for decision making in management of green spaces

    Molecular Epidemiology of Neisseria meningitidis Serogroup B in Brazil

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    Background: Neisseria meningitidis serogroup B has been predominant in Brazil, but no broadly effective vaccine is available to prevent endemic meningococcal disease. To understand genetic diversity among serogroup B strains in Brazil, we selected a nationally representative sample of clinical disease isolates from 2004, and a temporally representative sample for the state of SĂŁo Paulo (1988-2006) for study (n = 372). Methods: We performed multi-locus sequence typing (MLST) and sequence analysis of five outer membrane protein (OMP) genes, including novel vaccine targets fHbp and nadA. Results: In 2004, strain B:4:P1.15,19 clonal complex ST-32/ET-5 (cc32) predominated throughout Brazil; regional variation in MLST sequence type (ST), fetA, and porB was significant but diversity was limited for nadA and fHbp. Between 1988 and 1996, the SĂŁo Paulo isolates shifted from clonal complex ST-41/44/Lineage 3 (cc41/44) to cc32. OMP variation was associated with but not predicted by cc or ST. Overall, fHbp variant 1/subfamily B was present in 80% of isolates and showed little diversity. The majority of nadA were similar to reference allele 1. Conclusions: A predominant serogroup B lineage has circulated in Brazil for over a decade with significant regional and temporal diversity in ST, fetA, and porB, but not in nadA and fHbp

    Improved Canine and Human Visceral Leishmaniasis Immunodiagnosis Using Combinations of Synthetic Peptides in Enzyme-Linked Immunosorbent Assay

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    Visceral leishmaniasis is endemic in many areas of tropical and subtropical America where it constitutes a significant public health problem. It is usually diagnosed by enzyme-linked immunosorbent assays (ELISA) using crude Leishmania antigens, but a variety of other immunological methods may also be applied. Although these approaches are useful, historically their sensitivity and specificity have often been compromised by the use of complex mixtures of antigens. In this context, the use of combinations of purified, well-characterized antigens appears preferable and may yield better results. In the present study, combinations of peptides derived from the previously described Leishmania diagnostic antigens A2, NH, LACK and K39 were used in ELISA against sera from 106 dogs and 44 human patients. Improved sensitivities and specificities, close to 100%, for both sera of patients and dogs was observed for ELISA using some combinations of the peptides, including the detection of VL in dogs with low anti-Leishmania antibody titers and asymptomatic infection. So, the use of combinations of B cell predicted synthetic peptides derived from antigens A2, NH, LACK and K39 may provide an alternative for improved sensitivities and specificities for immunodiagnostic assays of VL

    sodC-Based Real-Time PCR for Detection of Neisseria meningitidis

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    Real-time PCR (rt-PCR) is a widely used molecular method for detection of Neisseria meningitidis (Nm). Several rt-PCR assays for Nm target the capsule transport gene, ctrA. However, over 16% of meningococcal carriage isolates lack ctrA, rendering this target gene ineffective at identification of this sub-population of meningococcal isolates. The Cu-Zn superoxide dismutase gene, sodC, is found in Nm but not in other Neisseria species. To better identify Nm, regardless of capsule genotype or expression status, a sodC-based TaqMan rt-PCR assay was developed and validated. Standard curves revealed an average lower limit of detection of 73 genomes per reaction at cycle threshold (Ct) value of 35, with 100% average reaction efficiency and an average R2 of 0.9925. 99.7% (624/626) of Nm isolates tested were sodC-positive, with a range of average Ct values from 13.0 to 29.5. The mean sodC Ct value of these Nm isolates was 17.6±2.2 (±SD). Of the 626 Nm tested, 178 were nongroupable (NG) ctrA-negative Nm isolates, and 98.9% (176/178) of these were detected by sodC rt-PCR. The assay was 100% specific, with all 244 non-Nm isolates testing negative. Of 157 clinical specimens tested, sodC detected 25/157 Nm or 4 additional specimens compared to ctrA and 24 more than culture. Among 582 carriage specimens, sodC detected Nm in 1 more than ctrA and in 4 more than culture. This sodC rt-PCR assay is a highly sensitive and specific method for detection of Nm, especially in carriage studies where many meningococcal isolates lack capsule genes

    Characterization of the Rabbit Neonatal Fc Receptor (FcRn) and Analyzing the Immunophenotype of the Transgenic Rabbits That Overexpresses FcRn

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    The neonatal Fc receptor (FcRn) regulates IgG and albumin homeostasis, mediates maternal IgG transport, takes an active role in phagocytosis, and delivers antigen for presentation. We have previously shown that overexpression of FcRn in transgenic mice significantly improves the humoral immune response. Because rabbits are an important source of polyclonal and monoclonal antibodies, adaptation of our FcRn overexpression technology in this species would bring significant advantages. We cloned the full length cDNA of the rabbit FcRn alpha-chain and found that it is similar to its orthologous analyzed so far. The rabbit FcRn - IgG contact residues are highly conserved, and based on this we predicted pH dependent interaction, which we confirmed by analyzing the pH dependent binding of FcRn to rabbit IgG using yolk sac lysates of rabbit fetuses by Western blot. Using immunohistochemistry, we detected strong FcRn staining in the endodermal cells of the rabbit yolk sac membrane, while the placental trophoblast cells and amnion showed no FcRn staining. Then, using BAC transgenesis we generated transgenic rabbits carrying and overexpressing a 110 kb rabbit genomic fragment encoding the FcRn. These transgenic rabbits – having one extra copy of the FcRn when hemizygous and two extra copies when homozygous - showed improved IgG protection and an augmented humoral immune response when immunized with a variety of different antigens. Our results in these transgenic rabbits demonstrate an increased immune response, similar to what we described in mice, indicating that FcRn overexpression brings significant advantages for the production of polyclonal and monoclonal antibodies

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio
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