29 research outputs found
Synthesis and characterization of electrical conductive bacterial cellulose-graft-polyaniline
Dissertação de mestrado em Micro-Nano TecnologiasIn recent years, conductive polymeric nanomaterials have received considerable attention
because of the increasing demand of new technologies for the development of electronic devices,
sensors, scaffolds, to be used in the most diverse research areas such as biology, tissue
engineering, food industry, etc.
In this context interest in polyaniline (PANI) has grown exponentially, being regarded as one of
the most technologically capable electrical conducting polymers, due to its high electrical
conductivity, easy synthesis, low cost, and stable electrical conductivity. Bacterial cellulose (BC)
nanofibers appear as very promising support material for these conductive additives due to their
high strength and stiffness associated to high purity, high porosity, and biocompatibility. The
combination of these two materials opens a new field of potential applications for bacterial
cellulose.
This project aim was to develop an electrical conductive bacterial cellulose-graft-polyaniline
composite by means of the oxidative-radical copolymerization using ammonium persulfate in
acidic medium. The grafting conditions were studied by varying grafting parameters: monomer
concentration and polymerization time.
Different methods were studied for the producing of the conductive BC-graft-PANI composites: in
situ direct polymerization of aniline in BC discs; surface modification of BC; and sulfonation of
BC. The electrical conductivity increased from 7.5*10-11 S/cm to 2.26*10-4 S/cm by controlling
the time of polymerization and the molar Ratio of CB:aniline. Under the assayed experimental
conditions, the optimum grafting efficiency was find at a CB:aniline ratio of 1:10 and with a time
reaction of 6 hours.
The produced BC-graft-PANI composites were characterized using conductivity assays, scanning
electron microscopy (SEM), fourier-transformed infrared spectroscopy (FTIR), thermogravimetric
analysis (TGA), differential scanning calorimetry (DSC), and viability assay (MTS test) taking BC
as reference.Nos últimos anos, os polímeros condutores tem recebido especial atenção devido há crescente
necessidade de novas tecnologias para o de envolvimento de dispositivos electrónicos, sensores,
suportes porosos, que poderão ser usados nas mais diversas áreas como a biologia, a
engenharia de tecidos, a industria alimentar, etc..
Neste contexto, o interesse na polianilina (PANI) tem crescido exponencialmente, sendo
considerada um dos polímeros condutores mais promissores, devido à sua elevada
condutividade eléctrica, fácil síntese, baixo custo e estabilidade térmica. No que diz respeito às
nanofibras de celulose bacteriana, estas surgem como um material de suporte muito
interessante para este tipo de polímeros condutores devido às excelentes propriedades
mecânicas, associadas á elevada pureza, elevada porosidade, e biocompatibilidade. Com a
combinação destes dois materiais abre-se um novo campo de aplicações para a celulose
bacteriana.
Este projecto tem como objectivo o desenvolvimento de um material compósito condutor à base
de celulose bacteriana e polianilina através da polimerização oxidativa in situ da anilina em meio
acido e usando persulfato de amónia como agente oxidante. As condições de polimerização
foram estudadas fazendo variar os parâmetros de reacção: concentração do monómero e tempo
de polimerização.
Para a produção dos compósitos BC/PANI foram estudados diferentes métodos: a polimerização
directa in situ da anilina na celulose bacteriana em meio ácido; modificação da superfície da
celulose bacteriana, através da activação inicial da superfície da CB e posterior polimerização
oxidativa; e sulfonação da celulose bacteriana. A condutividade eléctrica aumentou de 7.5*10-11
S/cm para 2.26*10-4 S/cm controlando o tempo de polimerização e a razão molar BC:anilina.
Para as condições analisadas, os melhores resultados obtidos foram a razão molar CB:anilina de
1:10 e um tempo de reacção de 6 horas.
Os materiais obtidos foram caracterizados através de ensaios de condutividade, microscopia
electrónica de varrimento (SEM), espectroscopia de infravermelho (FTIR), analise
termogravimétrica (TGA), calorimetria diferencial de varrimento (DSC), e ensaios de viabilidade
(teste MTS), usando a celulose bacteriana como referência
A resectorization of fire brigades in the north of Portugal
Sectorization can be regarded as a division of a territory into smaller regions
to deal with a complex problem involving multiple-criteria.
Resectorization intends to achieve another sectorization, according to some
new conditions but avoiding substantial changes.
An example of this can be the distribution of geographical areas by fire
brigades. In Portugal, fire brigades must protect and rescue the population in
the areas surrounding their fire stations. So we will use the current sectorization,
the geographic and population characteristics of the areas and the fire brigades’
response capacity to provide an optimised resectorization, in order to decrease
rescue time.
To achieve that, we will use a decision support system using different optimisation
methods, such as Non-dominated Sorting Genetic Algorithm (NSGA
II), which provides an effective sectorization concerning compactness and equilibrium
criteria.info:eu-repo/semantics/acceptedVersio
Creating homogeneous sectors: criteria and applications of sectorization
Sectorization is the process of grouping a set of previously defined basic units (points or small areas) into a fixed number of sectors. Sectorization is also known
in the literature as districting or territory design, and is usually performed to
optimize one or more criteria regarding the geographic characteristics of the territory
and the planning purposes of sectors. The most common criteria are equilibrium,
compactness and contiguity, which can be measured in many ways.
Sectorization is similar to clustering but with a different motivation. Both aggregate
smaller units into groups. But, while clustering strives for inner similarity of
data, sectorization aims at outer homogeneity [1]. In clustering, groups should be
very different from each other, and similar points are classified in the same cluster.
In sectorization, groups should be very similar to each other, and therefore very
different points can be grouped in the same sector.
We classify sectorization problems into four types: basic sectorization, sectorization
with service centers, resectorization, and dynamic sectorization. A Decision
Support System for Sectorization, D3S, is being developed to deal with these four
types of problems. Multi-objective genetic algorithms were implemented in D3S
using Python, and a user-friendly web interface was developed using Django. Several
applications can be solved with D3S, such as political districting, sales territory
design, delivery service zones, and assignment of fire stations and health services to
the population.info:eu-repo/semantics/draf
a cross-sectional population-based study
Funding Information: We thank Prof. Carla Nunes (NOVA National School of Public Health – Universidade NOVA de Lisboa) for the valuable insights and discussions in the conceptualization of this project. We thank the EpiDoc Unit and EpiReumaPt team for conceptualizing, planning, and implementing the main research project. We also acknowledge the support of CHRC (UIDP/04923/2020), granted by national funds through Fundação Ciência e Tecnologia, IP. Funding Information: This study received funding from an independent research grant (ID: 64165707) by Pfizer, and the first author received a grant from Fundação Ciência e Tecnologia, IP under the PhD grant SFRH/BD/148420/2019. The funders were not involved in study design; collection, analysis, or interpretation of data; or writing this article or the decision to submit it for publication. Publisher Copyright: © 2023, The Author(s).Background: Pain due to knee and / or hip osteoarthritis (HKOA) is the most common symptom for seeking healthcare. Pain interferes on daily activities, social and occupational participation in people with HKOA. The goal of this study is to estimate the prevalence of unmanageable pain levels (UPL) among people with HKOA), characterize this population and identify factors associated with UPL, and compare therapeutic strategies used by people with UPL versus manageable pain levels (MPL). Methods: We analysed data from the EpiReumaPt study (n = 10,661), that included a representative sample of the Portuguese population. Among these, 1081 participants had a validated diagnosis of HKOA by a rheumatologist. Sociodemographic, lifestyle and health-related data were collected in a structured interview. Pain intensity (NPRS) data were collected in a medical appointment. Painmedication (last month), physiotherapy and surgery were considered as therapies for pain management. UPL was defined as a mean pain intensity in the previous week of ≥5 points on 11-point numeric pain rating scale. The factors associated with UPL were analyzed with logistic regression (p < 0.05, 95%CI). The effect of unmanageable pain levels was assessed by the HOOS/KOOS activities of daily living and quality of life subscales. Symptoms of anxiety and depression were assessed by the Hospital Anxiety and Depression Scale (HADS). Analysis was completed with linear and logistic regression. All analysis were weighted. Results: The estimated prevalence of UPL among people with HKOA was 68.8%. UPL was associated with being female (odds ratio (OR) = 2.36, p < 0.001), being overweight (OR = 1.84, p = 0.035) or obese (OR = 2.26, p = 0.006), and having multimorbidity (OR = 2.08, p = 0.002). People with UPL reported worse performance in activities of daily living and lower quality of life (β = − 21.28, p < 0.001 and β = − 21.19, p < 0.001, respectively) than people with MPL. People with UPL consumed more NSAIDs (22.0%, p = 0.003), opioids (4.8%, p = 0.008), paracetamol (2.7%, p = 0.033), and overall analgesics (7.3%, p = 0.013) than people with MPL. A higher proportion of people with UPL underwent physiotherapy (17.5%, p = 0.002) than people with MPL. Conclusion: Two-thirds of people with HKOA in Portugal have poor management of their pain levels. Clinical and lifestyle factors, that are highly presented in individuals with HKOA, are associated with unmanageable pain. Our results highlighting the need for further research and implementation of effective interventions to improve pain, function and quality of life in people with HKOA.publishersversionpublishe
Cysteine allows ovarian cancer cells to adapt to hypoxia and to escape from carboplatin cytotoxicity
The authors would like to acknowledge the Instituto Portugues de Oncologia de Lisboa Francisco Gentil (IPOLFG) for partially funding the project. We would also like to acknowledge Dr Dialina Brilhante and Dr. Teresa Guerreiro (Servico de Imuno-hemoterapia, IPOLFG) for providing blood donors samples; to Dr Humberto Goncalves (Pharmacy, IPOLFG) for paclitaxel and carboplatin preparation, and Marta Teixeira (IBET) for the technical support in 3D models. The study was also funded by Projecto TVI. This research was supported by Fundacao para a Ciencia e Tecnologia (FCT) (PhD ProRegeM program, PD/BD/105893/2014, FCT fellowship, PD/BD/105768/2014). iNOVA4Health - UID/Multi/04462/2013, a program financially supported by Fundacao para a Ciencia e Tecnologia/Ministerio da Educacao e Ciencia, through national funds and co-funded by FEDER under the PT2020 Partnership Agreement is acknowledged.Ovarian cancer is the second most common gynaecologic malignancy and the main cause of death from gynaecologic cancer, due to late diagnosis and chemoresistance. Studies have reported the role of cysteine in cancer, by contributing for hydrogen sulphide (H2S) generation and as a precursor of glutathione (GSH). However, the role of cysteine in the adaptation to hypoxia and therapy response remains unclear. We used several ovarian cancer cell lines, ES2, OVCAR3, OVCAR8, A2780 and A2780cisR, to clarify cysteine relevance in ovarian cancer cells survival upon hypoxia and carboplatin. Results show that ES2 and OVCAR8 cells presented a stronger dependence on cysteine availability upon hypoxia and carboplatin exposure than OVCAR3 cells. Interestingly, the A2780 cisR, but not A2780 parental cells, benefits from cysteine upon carboplatin exposure, showing that cysteine is crucial for chemoresistance. Moreover, GSH degradation and subsequent cysteine recycling pathway is associated with ovarian cancer as seen in peripheral blood serum from patients. Higher levels of total free cysteine (Cys) and homocysteine (HCys) were found in ovarian cancer patients in comparison with benign tumours and lower levels of GSH were found in ovarian neoplasms patients in comparison with healthy individuals. Importantly, the total and S-Homocysteinylated levels distinguished blood donors from patients with neoplasms as well as patients with benign from patients with malignant tumours. The levels of S-cysteinylated proteins distinguish blood donors from patients with neoplasms and the free levels of Cys in serum distinguish blood from patients with benign tumours from patients with malignant tumours. Herein we disclosed that cysteine contributes for a worse disease prognosis, allowing faster adaptation to hypoxia and protecting cells from carboplatin. The measurement of serum cysteine levels can be an effective tool for early diagnosis, for outcome prediction and follow up of disease progression.publishersversionpublishe
COVID-19 collaborative screening: an action-research project for large scale contact tracing in Northern Portugal
In late November 2020, when Europe reached the highest 14-day incidence of COVID-19 cases, the resource-intensive and time-consuming traditional contact tracing performed by Public Health was challenged. In this context, innovative approaches were necessary to guarantee a timely interruption of disease transmission. “COVID-19 Collaborative Screening” Project was developed as a faster solution, not only because the contact tracing process is simpler for the operator, but mainly because it is possible to quickly scale up the number of operators involved. It was designed to interrupt family and social transmission chains, in a partnership with the Local Public Health Services – allowing these services to dedicate to scenarios of more complex risk assessment, using the traditional contact tracing. To perform contact tracing, this method involves Public Servants, Armed Forces and Medical Dentists. The Project also promotes participatory citizenship, by delegating to the citizen the responsibility of registering his/hers contacts with high-risk exposure in an online form, in contrast to the traditional contact tracing method which is more health professional-dependent. Until the end of January 2021, the Project has trained eight teams, enrolling a total of 213 professionals, and was implemented in eight Health Regions (with an estimated population of 1,346,150 inhabitants). The Project was successful at facing the delays in case interview and contact tracing. The strategy implemented by ColabCOVID is assembled as a sustainable, reproducible and scalable platform and is ready to be re-implemented to face the emergence of more contagious variants, as well as an eventual forthcoming health threat
Staff SARS-CoV-2 Seroprevalence and Mental Health as Key Factors in University Response to COVID-19 Pandemic
Copyright © 2021 Lopes, Henriques, Santos-Dias, Nunes-da-Silva, Gonçalves, de Sousa, Abdulghani, Eletério, Braga, Soares, Branco, Canhão and Rodrigues.Background: In response to rapid global spread of the newly emerged coronavirus disease 2019 (COVID-19), universities transitioned to online learning and telework to decrease risks of inter-person contact. To help administrators respond to the COVID-19 pandemic and better understand its impacts, we surveyed SARS-CoV-2 seroprevalence among NOVA University employees and assessed community mental health. Methods: Data were collected from voluntary participants at six NOVA University locations, in the Lisbon metropolitan area, from June 15-30, 2020. All subjects provided written informed consent. Of 1,627 recruited participants (mean age 42.0 ± 12.3 years), 1,624 were tested. Prior to blood collection, participants completed a questionnaire that assessed: COVID-19 symptoms during the previous 14 days, chronic non-communicable diseases, chronic medication, anxiety, and depression symptoms. SARS-CoV-2 serology tests were then performed, and results communicated approximately 4 days after blood draw. Participants with positive serology tests were contacted to assess COVID-19 symptoms since February. Results: Estimated prevalence of SARS-CoV-2 IgG antibodies was 3.1% (n = 50), of which 43.5% reported symptoms in the previous 4 months. The Medical School had the highest seroprevalence (6.2%). Participants reported having at least one chronic disease (63.7%), depression-like symptoms (2.1%), and anxiety symptoms (8.1%). Rates of depression and anxiety symptoms were significantly higher in women, with sleep hours and occasional alcohol consumption negatively associated with depression. Male gender, older age, and sleep hours negatively associated with anxiety symptoms. School of employment and presence of comorbidities positively associated with anxiety. Conclusion: By measuring seroprevalence of SARS-CoV-2 antibodies among NOVA employees and assessing subjects' mental health, we aim to help administrators at European public universities in urban areas, such as Lisbon, Portugal, better understand the needs of their communities. This study resulted in implementation of a stricter contingency plan in the Medical School, while other schools continued to follow Government mitigation guidelines. These findings may also guide the development of tailored strategies to ensure physical and mental health of the academic community during this pandemic crisis. We conclude that, together with COVID-19 contingency plans, psychological support services and facilities to help people effectively face pandemic-associated challenges and minimise anxiety and depression should be implemented.publishersversionpublishe
Ecotoxicological evaluation of electrochemical oxidation for the treatment of sanitary landfill leachates
In this study, the efficiency of electrochemical oxidation to treat a sanitary landfill leachate was evaluated by the reduction in physico-chemical parameters and in ecotoxicity. The acute toxicity of the sanitary landfill leachates, before and after treatment, was assessed with the model organism Daphnia magna. Electrochemical oxidation treatment was effective in the removal of organic load and ammonium nitrogen and in the reduction of metal ions concentrations. Furthermore, a reduction of 2.5-fold in the acute toxicity towards D. magna after 36 h of treatment was noticed. Nevertheless, the toxicity of the treated leachate is still very high, and further treatments are necessary in order to obtain a non-toxic effluent to this aquatic organism. Toxicity results were also compared with others described in the literature for different leachate treatments and test organisms
A complex scenario of tuberculosis transmission is revealed through genetic and epidemiological surveys in Porto
Tuberculosis (TB) incidence is decreasing worldwide and eradication is becoming plausible. In low-incidence countries, intervention on migrant populations is considered one of the most important strategies for elimination. However, such measures are inappropriate in European areas where TB is largely endemic, such as Porto in Portugal. We aim to understand transmission chains in Porto through a genetic characterization of Mycobacterium tuberculosis strains and through a detailed epidemiological evaluation of cases.This work was developed under the scope of the project NORTE-01-0145-FEDER-000013, supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (FEDER), and supported by contributions from Iceland, Liechtenstein and Norway through the European Economic Area Grants under the Public Health Initiative programme, (PT06, Project 000138DT1). TR is supported by the Portuguese Foundation for Science and Technology (FCT) through a post-doctoral grant (SFRH/BPD/108126/2015)info:eu-repo/semantics/publishedVersio
Hexapoda Yearbook (Arthropoda: Mandibulata: Pancrustacea) Brazil 2020: the first annual production survey of new Brazilian species
This paper provided a list of all new Brazilian Hexapoda species described in 2020. Furthermore, based on the information extracted by this list, we tackled additional questions regarding the taxa, the specialists involved in the species descriptions as well as the journals in which those papers have been published. We recorded a total of 680 new Brazilian species of Hexapoda described in 2020, classified in 245 genera, 112 families and 18 orders. These 680 species were published in a total of 219 articles comprising 423 different authors residing in 27 countries. Only 30% of these authors are women, which demonstrates an inequality regarding sexes. In relation to the number of authors by species, the majority of the new species had two authors and the maximum of authors by species was five. We also found inequalities in the production of described species regarding the regions of Brazil, with Southeast and South leading. The top 10 institutions regarding productions of new species have four in the Southeast, two at South and with one ate North Region being the outlier of this pattern. Out of the total 219 published articles, Zootaxa dominated with 322 described species in 95 articles. The average impact factor was of 1.4 with only seven articles being published in Impact Factors above 3, indicating a hardship on publishing taxonomic articles in high-impact journals.The highlight of this paper is that it is unprecedent, as no annual record of Hexapoda species described was ever made in previous years to Brazil.Fil: Silva Neto, Alberto Moreira. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: Lopes Falaschi, Rafaela. Universidade Estadual do Ponta Grossa; BrasilFil: Zacca, Thamara. Universidade Federal Do Rio de Janeiro. Museu Nacional; BrasilFil: Hipólito, Juliana. Universidade Federal da Bahia; BrasilFil: Costa Lima Pequeno, Pedro Aurélio. Universidade Federal de Roraima; BrasilFil: Alves Oliveira, João Rafael. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: Oliveira Dos Santos, Roberto. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: Heleodoro, Raphael Aquino. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: Jacobina, Adaiane Catarina Marcondes. Universidade Federal do Paraná; BrasilFil: Somavilla, Alexandre. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: Camargo, Alexssandro. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: de Oliveira Lira, Aline. Universidad Federal Rural Pernambuco; BrasilFil: Sampaio, Aline Amanda. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: da Silva Ferreira, André. Universidad Federal Rural Pernambuco; BrasilFil: Martins, André Luis. Universidade Federal do Paraná; BrasilFil: Figueiredo de Oliveira, Andressa. Universidade Federal do Mato Grosso do Sul; BrasilFil: Gonçalves da Silva Wengrat , Ana Paula. Universidade do Sao Paulo. Escola Superior de Agricultura Luiz de Queiroz; BrasilFil: Batista Rosa, Augusto Henrique. Universidade Estadual de Campinas; BrasilFil: Dias Corrêa, Caio Cezar. Universidade Federal Do Rio de Janeiro. Museu Nacional; BrasilFil: Costa De-Souza, Caroline. Museu Paraense Emilio Goeldi; BrasilFil: Anjos Dos Santos, Danielle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagónica. Universidad Nacional de la Patagonia "San Juan Bosco". Centro de Investigación Esquel de Montaña y Estepa Patagónica; ArgentinaFil: Pacheco Cordeiro, Danilo. Instituto Nacional Da Mata Atlantica; BrasilFil: Silva Nogueira, David. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: Almeida Marques, Dayse Willkenia. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: Nunes Barbosa, Diego. Universidade Federal do Paraná; BrasilFil: Mello Mendes, Diego Matheus. Instituto de Desenvolvimento Sustentável Mamirauá; BrasilFil: Galvão de Pádua, Diego. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: Silva Vilela, Diogo. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Gomes Viegas, Eduarda Fernanda. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: Carneiro dos Santos, Eduardo. Universidade Federal do Paraná; BrasilFil: Rodrigues Fernandes, Daniell Rodrigo. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; Brasi