73 research outputs found
Uma revisão sistemática
Introdução:A Perturbação Depressiva Major é caracterizada por humor depressivo, perda
de interesse ou prazer, ideias de culpa ou de autoestima baixa, perturbações do sono e
do apetite, sensação de cansaço e dificuldades de concentração. Para além dos fármacos
antidepressivos, a Psicoterapia Cognitivo-Comportamental é um dos tipos de terapia
psicológica que demonstrou eficácia no tratamento da depressão ligeira a moderada. No
entanto, a eficácia da psicoterapia depende de vários fatores relacionados com o doente,
com as características da depressão e com o próprio terapeuta.
Objetivo: Determinar quais são os fatores que permitem prever se um doente com
depressão vai responder à Terapia Cognitivo-Comportamental.
Métodos: Nesta revisão sistemática da literatura incluímos ensaios aleatorizados
controlados que avaliassem a influência de determinados fatores na resposta da
depressão à Terapia Cognitivo-Comportamental. Fizemos pesquisa na PubMed para
encontrar estudos publicados entre 1999 e novembro de 2019 sobre essa temática. Todos
os títulos e abstracts foram avaliados de forma independente por dois revisores. O risco
de viés foi avaliado segundo a “Revised Cochrane risk-of-bias tool for randomized
trials”. A intensidade dos sintomas depressivos foi o único outcome.
Resultados: Níveis mais elevados de sintomas de perturbação da personalidade
comórbida, uma maior intensidade da aliança do paciente para com o processo
terapêutico, ser casado ou coabitar, volumes maiores do córtex cingulado anterior rostral
direito, baixos níveis de persistência e níveis baixos a moderados de aprendizagem e
memória verbais são fatores preditores da resposta da Perturbação Depressiva Major à
Terapia Cognitivo-Comportamental. Em doentes com doença de Parkinson, a participação
do cuidador no tratamento também é um preditor de resposta.
Discussão: Os possíveis fatores preditores analisados influenciam diretamente o processo
psicoterapêutico porque interferem com a relação que o doente cria com o mesmo, ao
mesmo tempo que afetam a performance do terapeuta, sendo deduzível a sua influência
na resposta ao tratamento. A exceção é o volume do córtex cingulado anterior rostral
direito, que, ao invés de influenciar diretamente a dinâmica terapêutica, pode ajudar a
compreender melhor a anatomia mediadora do tratamento e sugerir alvos neuronais para
aumentar a resposta à Terapia Cognitivo-Comportamental. Conclusões: Os possíveis fatores preditores analisados nos treze estudos diziam respeito
a características do doente, do tratamento, da clínica e respetiva gravidade, anatomia
cerebral e adversidades na infância. Recomendamos que mais estudos sejam realizados
na Europa sobre esta temática.Introduction: Major Depressive Disorder is characterized by depressed mood, loss of
interest or pleasure, ideas of guilt or low self-esteem, disturbances in sleep and
appetite, feeling tired and concentration difficulties. In addition to antidepressant drugs,
CognitiveBehavioral Psychotherapy is one of the types of psychological therapy that has
shown effectiveness in the treatment of mild to moderate depression. However, the
effectiveness of psychotherapy depends on several factors related to the patient, the
characteristics of depression and the therapist himself.
Objective: To determine what are the factors that allow predicting whether a patient
with depression will respond to Cognitive Behavioral Therapy.
Methods: In this systematic review of the literature, we included randomized controlled
trials that assessed the influence of certain factors on the response of depression to
cognitive behavioral therapy. We did research at PubMed to find studies published
between 1999 and November 2019 on this topic. All titles and abstracts were
independently assessed by two reviewers. The risk of bias was assessed according to the
“Revised Cochrane risk-of-bias tool for randomized trials”. The intensity of depressive
symptoms was the only outcome.
Results: Higher levels of symptoms of comorbid personality disorder, greater intensity of
the patient's alliance with the therapeutic process, being married or cohabiting, higher
volumes of the right rostral anterior cingulate cortex, low levels of persistence and low
to moderate levels of verbal learning and memory are predictors of the Major Depressive
Disorder response to Cognitive Behavioral Therapy. In patients with Parkinson's
disease, the caregiver's participation in treatment is also a predictor of response.
Discussion: The possible predictive factors analyzed directly influence the
psychotherapeutic process because they interfere with the relationship that the patient
creates with him, while they affect the performance of the therapist, being deductible
his influence in the response to the treatment. The exception is the volume of the right
rostral anterior cingulate cortex, which, instead of directly influencing the therapeutic
dynamics, can help to better understand the mediating anatomy of the treatment and
suggest neuronal targets to increase the response to CognitiveBehavioral Therapy. Conclusion: The possible predictive factos analyzed in the thirteen studies concerned
the patient’s characteristics, treatment, clinic and respective severity, brain anatomy
and childhood adversities. We recommend that more studies be carried out in Europe on
this subject
Estudo da reciclagem de resíduos de fibras de vidro em geopolímeros, argamassas e telas de impermeabilização
Mestrado em Engenharia de MateriaisDesenvolveu-se uma parceria entre a Universidade de Aveiro, Ria Blades, S.A. e Saint-Gobain Weber Portugal, S.A. com objetivo de encontrar formas de aproveitamento dos resíduos de fibra de vidro produzidos na Ria Blades, S.A., que atualmente são depositados em aterro.
O trabalho incidiu em três produtos-alvo: telas de impermeabilização, argamassas e geopolímeros.
No que diz respeito às telas de impermeabilização, de base polimérica (poliuretano), os resíduos foram aplicados como agente de reforço. Estudou-se o efeito da incorporação das fibras na aderência, na resistência à tração e na durabilidade perante ciclos de gelo-degelo. Quando incorporadas fibras de vidro, registou-se um aumento na aderência ao suporte relativamente à amostra padrão e um crescimento (de cerca de 20 vezes) na resistência à tração.
Na incorporação em argamassas bastardas, o objetivo foi perceber o efeito da substituição das fibras poliméricas atualmente usadas, pelas fibras de vidro residuais. Estudou-se o efeito na percentagem de ar incorporado e densidade do amassado, bem como a variação de massa e de dimensão, módulo de elasticidade, resistência à compressão e flexão do produto endurecido. A incorporação de fibra de vidro não aparenta prejudicar o desempenho das argamassas, sendo os resultados semelhantes nas amostras padrão. Apesar de as quantidades incorporadas serem apenas de 0,1%, é possível que a utilização destes resíduos tenha impactos economicamente positivos para as duas empresas.
Nos geopolímeros, a incorporação das fibras de vidro pretendeu explorar dois efeitos distintos: (i) como ligante, em substituição parcial de metacaulino (até 40% em massa); (ii) como agente de reforço da mistura. Numa primeira fase, foi necessário caracterizar as matérias primas e os resíduos para respeitar as razões molares que asseguram uma maior extensão da reação. Foram avaliadas a densidade aparente, resistência à compressão, absorção de água ao longo do tempo de cura e ainda a resistência à flexão no caso de as fibras funcionarem como agente de reforço. Como substituto parcial do metacaulino verifica-se uma descida na resistência à compressão com o aumento de resíduo de fibra de vidro. No entanto com a otimização da formulação com 20% de fibras de vidro foi possível duplicar o valor da resistência à compressão (> 8MPa). Como agente de reforço, os resultados mostram ganhos de resistência à compressão de 4 vezes quando se incorporam fibras de 6mm de comprimento, relativamente a amostras sem reforço. O uso de fibras mais longas (20mm) é mais eficaz no aumento da resistência à flexão.A partnership has been developed between the University of Aveiro, Ria Blades, S.A. and Saint-Gobain Weber Portugal, S.A. in order to find a way to recycle the glass-fibre residues produced from Ria Blades, S.A. that are currently being send to landfill.
Three possible target-products were exploited: waterproofing membrane, mortars and geopolymers.
On the waterproofing membrane, based on polyurethane, the residues were incorporated as reinforcing agents and effects on adhesion, tensile strength and resistance to freeze-thaw cycles were determined. An increase of 20 times on the tensile strength has been registered, relatively to the standard sample.
On mortars, the aim was to understand the effect of the substitution of the currently used reinforcing-fibres for the wasted glass-fibres. Fresh-state properties such as the entrained air content and density were evaluated. The effect on relevant hardened-state properties was then studied, including the variation of mass and dimensions, the compressive and flexural strengths, and elastic modulus. The behaviour of the mortars doesn’t seem to be affected by the incorporation of glass-fibres because the results from both the mortars with and without glass-fibres are similar. Although the quantity of incorporated glass-fibres is only around 0,1%, its use may have positive economic benefits for both companies.
In geopolymers, the incorporation of wasted glass-fibres aimed to explore two distinct effects: (i) use as binder, partially substituting the metakaolin (up to 40 wt.%); (ii) use as reinforcing agent of common matrixes. On the first stage it was necessary to characterize both the raw materials and the glass-fibres, in order to achieve the desirable molar ratios that assure an extended reaction. Hardened samples were characterized in terms of density, compressive strength and water absorption. In the attempted reinforced geopolymers the flexural strength was additionally tested. When the glass-fibres were used as partial substitute of metakaolin, a drop of the compressive strength was observed for higher contents of glass-fibres. Optimizing the mixture for 20 % of glass-fibres allowed to duplicate the compressive strength (> 8 MPa). When 6 mm glass-fibres were used as a reinforcing agent, the compressive strength increased 4 times when compared to samples without reinforcement. Using 20 mm fibres is the most effective way of improving flexural strength
Innovative application for bauxite residue: red mud-based inorganic polymer spheres as pH regulators
In this study, and for the first time, red mud (RM)-based geopolymer spheres were synthesised, with varying porosity and RM content, and then their use as pH regulators was evaluated. The aluminosilicate sources of these inorganic polymers were 100% waste-based, consisting of a mixture of RM and fly ash wastes. Geopolymer spheres containing up to 60 wt.% RM were successfully produced, while higher RM contents distorted the specimens' spherical shape. Results showed that alkalis leaching from the spheres over time can be controlled by their porosity, while the RM content induces only minor changes to leaching. The RM-based spheres leached up to 0.0237 mol/dm3g of OH- ions from their structure, this being among the highest values ever reported for geopolymers. This allowed a continuous and prolonged pH buffer capacity with narrow pH decay over the 28 days (2.4 pH units), suggesting the use of the RM-based spheres as pH buffering materials in wastewater treatment and anaerobic digestion systems.publishe
Highly efficient lead extraction from aqueous solutions using inorganic polymer foams derived from biomass fly ash and metakaolin
This work reports a simple and safe, but powerful, route to depollute lead-containing aqueous solutions. Inorganic polymer foams (cm-size) were used as bulk-type adsorbents. The influence of the specimens' porosity and activator molarity on the foams' physical properties and on their lead extraction ability was studied. Then, the best performing samples were deeply evaluated as lead adsorbents by studying the impact of pH, lead concentration, contact time, ionic strength and solution volume. Lead sorption kinetics is strongly affected by the pollutant concentration, pH and the solution ionic strength. Under the most favourable conditions the foams showed an impressive removal capacity (105.9 mg/g at pH 5, 23 °C, C0 = 800 ppm, deionised water), surpassing all other reported values on the use of bulk-type inorganic polymers. The foams’ lead uptake is 2.3 times higher than the previous best performing bulk-type specimens (mm-size spheres), and sorption is 12.5–15 times faster. The foams can be easily regenerated using mild acidic conditions, and then reused as adsorbent, suggesting that the main adsorption mechanism is ion exchange
In-depth investigation of the long-term strength and leaching behaviour of inorganic polymer mortars containing green liquor dregs
Green liquor dregs are the most challenging waste stream coming from the pulp and paper industry. Despite tremendous efforts, there are not currently any viable recycling alternatives for this massively produced waste (2 Mt/year), which inevitably ends up in landfills. Urgent actions must be undertaken to tackle this. In this work, a substantial amount of dregs was incorporated into eco-friendly, waste-based inorganic polymer (geopolymer) mortars as fine filler. Then, and for the first time, the long-term strength performance (up to 270 days) and heavy metals leaching behaviour of the dregs-containing mortars was evaluated. The effect of the mixture composition and dregs incorporation content on the fresh- and hardened-state properties of the mortars was also studied. Dregs were found to increase the initial and final setting time of the slurries, thus extending the open time before their in-situ application. The use of dregs as fine filler effectively enhances the compressive strength of the mortars, and decreases their water absorption levels. These eco-friendly building materials showed excellent long-term performance, as their strength continuously increases up to the 270th day (after mixture), and no signs of efflorescence formation were detected. Moreover, the heavy metals leaching levels of the mortars were well below the contamination limits in soil, which demonstrates the feasibility of this recycling methodology.publishe
Unravelling the Affinity of Alkali-Activated Fly Ash Cubic Foams towards Heavy Metals Sorption
In this work, alkali-activated fly ash-derived foams were produced at room temperature by direct foaming using aluminum powder. The 1 cm3 foams (cubes) were then evaluated as adsorbents to extract heavy metals from aqueous solutions. The foams’ selectivity towards lead, cadmium, zinc, and copper ions was evaluated in single, binary, and multicomponent ionic solutions. In the single ion assays, the foams showed much higher affinity towards lead, compared to the other heavy metals; at 10 ppm, the removal efficiency reached 91.9% for lead, 83.2% for cadmium, 74.6% for copper, and 64.6% for zinc. The greater selectivity for lead was also seen in the binary tests. The results showed that the presence of zinc is detrimental to cadmium and copper sorption, while for lead it mainly affects the sorption rate, but not the ultimate removal efficiency. In the multicomponent assays, the removal efficiency for all the heavy metals was lower than the values seen in the single ion tests. However, the superior affinity for lead was preserved. This study decreases the existing knowledge gap regarding the potential of alkali-activated materials to act as heavy metals adsorbents under different scenarios
Synthesis of red mud derived M-type barium hexaferrites with tuneable coercivity
Hexagonal ferrites can be employed in a multitude of applications, the most common hexaferrites are the M ferrites such as BaFe12O19 (barium hexaferrite, BaM). It is known that if Fe3+ is substituted with a combination of Ti4+/Co2+ the coercivity of BaM can be reduced to produce soft M ferrites with easily switchable magnetisation. They can be utilised as powders, films or bulk ceramics, and can be manufactured from a wide variety of synthesis methods. The production of hexaferrites usually requires commercial raw materials, but if an industrial waste can be utilised, this will help to ease waste disposal and storage costs, valorise a waste material and encourage circular economy. In this study, bauxite residue (red mud) from the production of alumina was used to synthesise M-type hexaferrites, using a simple ceramic process. BaCO3, or BaCO3+Co3O4, were added to the red mud, blended and heated at 1000 °C to produce the M-type hexaferrites. Without cobalt addition up to 81.1 wt% M ferrite was produced, and with Co addition up to 74.3 wt% M ferrite was formed. Without cobalt, the M ferrite phase closely resembled BaFe9Al3O19, and was a hard ferrite with a magnetisation of 12–19 A m2/kg for the whole powder (up to 23.6 A m2/kg for the M ferrite phase) and a coercivity of ~290 kA/m. When cobalt was added, secondary titanate phases vanished, and Ti4+/Co2+ partially substituted very soft M ferrite was formed with a low coercivity of ~16 kA/m but a higher magnetisation of 24.5 A m2/kg for the whole powder (up to 34.9 A m2/kg for the M ferrite phase). Therefore, not only can good quality magnetic materials be easily produced from this common waste material, but its magnetic properties can be tuned by varying the 2 + ions added during the process
Synthesis of red mud derived M-type barium hexaferrites with tuneable coercivity
Hexagonal ferrites can be employed in a multitude of applications, the most common hexaferrites are the M ferrites such as BaFe12O19 (barium hexaferrite, BaM). It is known that if Fe3+ is substituted with a combination of Ti4+/Co2+ the coercivity of BaM can be reduced to produce soft M ferrites with easily switchable magnetisation. They can be utilised as powders, films or bulk ceramics, and can be manufactured from a wide variety of synthesis methods. The production of hexaferrites usually requires commercial raw materials, but if an industrial waste can be utilised, this will help to ease waste disposal and storage costs, valorise a waste material and encourage circular economy. In this study, bauxite residue (red mud) from the production of alumina was used to synthesise M-type hexaferrites, using a simple ceramic process. BaCO3, or BaCO3+Co3O4, were added to the red mud, blended and heated at 1000 °C to produce the M-type hexaferrites. Without cobalt addition up to 81.1 wt% M ferrite was produced, and with Co addition up to 74.3 wt% M ferrite was formed. Without cobalt, the M ferrite phase closely resembled BaFe9Al3O19, and was a hard ferrite with a magnetisation of 12–19 A m2/kg for the whole powder (up to 23.6 A m2/kg for the M ferrite phase) and a coercivity of ~290 kA/m. When cobalt was added, secondary titanate phases vanished, and Ti4+/Co2+ partially substituted very soft M ferrite was formed with a low coercivity of ~16 kA/m but a higher magnetisation of 24.5 A m2/kg for the whole powder (up to 34.9 A m2/kg for the M ferrite phase). Therefore, not only can good quality magnetic materials be easily produced from this common waste material, but its magnetic properties can be tuned by varying the 2 + ions added during the process.publishe
Red mud-based inorganic polymer spheres: innovative and environmentally friendly anaerobic digestion enhancers
Red mud-based inorganic polymer spheres were used as alternative pH regulators and process enhancers in sequencing batch anaerobic reactors treating cheese whey. This byproduct tends to quickly acidify under anaerobic conditions, and the common route to control pH and ensure suitable conditions for methane production involves the use of commercial alkaline raw materials. The spheres were synthesized using significant amounts of hazardous and toxic waste, red mud (50 wt% of solid components), whose recycling is challenging. The inorganic polymeric spheres, when compared to virgin alkaline raw materials, improved organic matter removal by 44%, prevented VFA accumulation (acidification degree less than 20%), maintained pH values in a range (6.5-7.2) to ensure maximum methanogenic activity by archaea microorganisms, and boosted the methane volume by ~90%. These promising results demonstrate the feasibility and performance advantages of using these innovative spheres instead of virgin raw materials, which is an important tool towards sustainable development.publishe
The Role of a Medical Intermediate Care Unit in the Management of Budd-Chiari Syndrome: Case Series
Budd-Chiari syndrome (BCS) has a wide spectrum of presentations, from an asymptomatic status to acute liver failure (ALF). The therapeutic approach depends on disease severity and related etiology with patients with severe forms of presentation classically managed in intensive care units (ICUs). Here, we report a series of five BCS patients managed in a medical intermediate care unit (IntCU), with three of them presenting with acute liver injury. Progression to ALF was seen in three patients, two of whom died, with one being successfully submitted to liver transplantation. IntCUs allow a 24-h patient surveillance and a prompt management of BCS, with less economic impact when compared to ICUs. Mortality was related to the presence of associated comorbidities that limited therapeutic approach.This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors
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