Linking cellular proteostasis to yeast longevity

Proteostasis is a cellular housekeeping process that refers to the healthy maintenance of the cellular proteome that governs the fate of proteins from synthesis to degradation. Perturbations of proteostasis might result in protein dysfunction with consequent deleterious effects that can culminate in cell death. To deal with the loss of proteostasis, cells are supplied with a highly sophisticated and interconnected network that integrates as major players the molecular chaperones and the protein degradation pathways. It is well recognized that the ability of cells to maintain proteostasis declines during ageing, although the precise mechanisms are still elusive. Indeed, genetic or pharmacological enhancement of the proteostasis network has been shown to extend lifespan in a variety of ageing models. Therefore, an improved understanding of the interventions/mechanisms that contribute to cellular protein quality control will have a huge impact on the ageing field. This mini-review centers on the current knowledge about the major pathways that contribute for the maintenance of Saccharomyces cerevisiae proteostasis, with particular emphasis on the developments that highlight the multidimensional nature of the proteostasis network in the maintenance of proteostasis, as well as the age-dependent changes on this network.This work was developed under the scope of the project NORTE01-0145-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). BSM is supported by the fellowship SFRH/BPD/90 533/2012 funded by the Fundac¸ao para a Ci ˜ encia e ˆ Tecnologia (FCT, Portugal)

Infinite transformation semigroups

In this thesis some topics in the field of Infinite Transformation Semigroups are investigated. In 1966 Howie considered the full transformation semigroup (x) on an infinite set x of cardinality m. For each in (x) he defined defect of = def and collapse of = C(a) to be the sets X \ X and { ∊ x : (∃∊ x, y ≠ ) X = Y }, respectively. Later, in 1981 he introduced the set S[sub]m̱ = { ∊ (x): |def | = | c() | = | ran | = m, |y [super]-1 | <m, (∀ y ∊ ran ) } which is a subsemigroup of (x) provided the cardinal m is regular. Taking m to be a regular cardinal number, Howie proved that S[sub]m̱ is then a bisimple, idempotent-generated semigroup of depth 4. Next he considered the congruence defined in S[sub]m̱ by △[sub]m̱ = {(, β) ∊ S[sub]m̱ x S[sub]m̱ : max (|D(, β) | , | D((, β) β | ) < m̱ } where D(, β) = { ∊ X : ≠ β } and showed that S[sub]m̱* = S[sub]m̱/ △[sub]m̱ is a bisimple, congruence-free and idempotent-generated semigroup of depth 4. In this thesis comparable results are obtained for the semigroup P[sub]m̱ which is the top principal factor of the semigroup [sub]m̱ = { ∊ (x): |def | = | c() | = m̱} Here it is no longer necessary to restrict to a regular cardinal m̱. The set S[sub]m̱ considered by Howie fails to be a subsemigroup of () if m̱ is not regular. It is shown that in this case = O[sub]m̱ . In the case where m̱ = ₀ (a regular cardinal) it is shown that △[sub]₀ is the only proper congruence on S[sub]m̱. Within the symmetric inverse semigroup (), the Baer-Levi semigroup B of type (m̱, m̱) on X is considered and a dual B* found. The products BB* and B*B are investigated and the semigroup Km̱ = is described. The top principal factor of Km̱ is denoted by Lm̱ and it is shown that Lm̱ = B*B ⋃ {O}. On the set Lm̱ a congruence δ[sub]m̱, closely analogous to the congruence △[sub]m̱ defined above, is considered, and it is shown that Lm̱ / δ[sub]m̱ is a o-bisimple, inverse and nilpotent-generated semigroup. Finally, two embedding theorems for inverse semigroups and semigroups in general are presented. The cardinalities of some of the semigroups introduced in this thesis are studied

Jovens, trabalho e cidadania: que sentido(s)

Vive-se hoje um período de profunda recomposição do mundo de trabalho e do emprego, fruto da competição internacional e de inovações tecnológicas e informáticas, que sustentam discursos sobre o "fim do trabalho”, o “emagrecimento” dos sistemas produtivos e, fundamentalmente, de “crise” do Estado-Providência. Paralelamente, assiste-se a um enfraquecimento de direitos sociais e vínculos contratuais entre trabalhadores e empresas, que, associado à redução da importância do sindicalismo e dos movimentos sociais, tende a configurar as relações de trabalho sob o signo de precariedade e/ou do desemprego. Daqui resultam alterações profundas nas relações de trabalho, nas posições e identidades laborais, no essencial, na cidadania individual e colectiva. A entrada no mercado de trabalho faz-se, sobretudo, através de modalidades flexíveis ou atípicas (contratos a termo, falsos recibo verde, trabalho temporário, etc.) ou em trabalhos subqualificados e sem correspondência com o perfil de formação profissional do candidato ao emprego. As taxas de desemprego atingem, em Portugal, valores históricos, tendo-se cifrado, no último trimestre de 2011, em 14%. Esta realidade afecta camadas heterogéneas da população, mas atinge sobretudo os mais jovens, cujas trajectórias profissionais tendem a ser marcadas pela transitoriedade, pela intermitência e pela alternância, inscrevendo-os na incerteza face ao futuro e limitando ou comprometendo projectos pessoais, sociais e afectivos. Neste cenário, os novos movimentos sociais protagonizados pelos mais jovens, ressentidos com a ausência de propostas para o futuro, reclamam a dignidade do trabalho e formas de democracia mais participativas. Estas ondas de protesto marcaram o ano de 2011, tanto que a revista Times escolheu "O Manifestante" como a personalidade do ano. Nesta obra, discute-se estas problemáticas e as novas formas de cidadania que as acompanham

Lead bioremoval by cork residues as biosorbent

The intensification of industrial activity during the last few years has greatly contributed to the increase of heavy metals in the environment, mainly in the aquatic systems [1]. Conventional technologies traditionally used for the removal of heavy metals from aqueous solutions are expensive and inefficient at low metal concentrations [2]. Biosorption, which is a property of different types of biomass (biosorbents) to bind and concentrate heavy metals from even very dilute aqueous solutions, is one of the most promising technologies that can be used for this purpose [3]. The goal of this work was to study the bioremoval process of Pb(II) ions from aqueous dilute solutions by cork granulates (1-2 mm) from a Portuguese cork processing company. The effect of physico-chemical parameters such as initial metal solution, pH, biomass cork pre-treatments and initial metal and biosorbent concentrations on the metal removal efficiency were investigated. The maximum Pb(II) uptake capacity (Qmax) of cork biomass was also determined from the Langmuir isotherm. The results obtained showed that the optimum initial pH for Pb(II) removal was in the range 3-4, leading to removal yields of about 90-100% for initial metal concentrations of 10-100 mg/L. Cork biomass without treatment provided a higher removal yield (93%) than the biomass submitted to previous extraction with deionised water (80%), ethyl acetate (83%) and ethanol (88 %). The Langmuir model showed a very good correlation with experimental results (r2=0.995) and the Qmax was determined as being 5.3 mg Pb(II)/g cork. The optimisation of continuous bioremoval of Pb(II) (10 mg/L) from 25 L of influent, regarding metal uptake yield and volume of effluent containing a Pb(II) concentration 1 mg/L (MAV), was carried out by the factorial design methodology, leading to the establishment of the best operating conditions. In these conditions, two fixed bed-reactors (operational liquid volume of each reactor containing 20g of biosorbent=138 mL) running in sequential mode (feed flow rate - 590 mL/h) were more efficient (effluent volume with [Pb(II)] 1 mg/L=10 L) than one reactor alone (effluent volume with [Pb(II)] 1 mg/L=5 L). Finally, the chemical characterization in terms of CQO, TOC and phenolic compounds of the effluent before discharge showed that all values were lower than the ones allowed by environmental legislation

Facebook: Risks and Opportunities in Brazilian and Portuguese Youths with Different Levels of Psychosocial Adjustment

This study aimed to assess the risks and opportunities associated with Facebook usage and to explore the moderating role of psychosocial (mal)adjustment, nationality and age in these relationships. This correlational study involved a sample of 452 Brazilian and 500 Portuguese youths, aged between 14 and 20 years. Results showed that these youths spent a daily average of 61-120 minutes on Facebook, three to four times per week, displaying a positive attitude towards its use. These characteristics were most notable in the Brazilian youths [t(950) = 5.64, p < .001; t(950) = –5.07, p < .001; and t(950) = – 6.85, p < .001, respectively]. The Portuguese youths ran more risks than the Brazilians [t(950) = 6.36, p < .001], but both youths equally enjoyed the opportunities. In the case of the Portuguese youths, the risks and opportunities were moderated by the frequency of use, in other words “the higher the usage, the more risks and opportunities” (β = –.235 p < .001and β = –.167, p < .001, respectively). The psychosocial adjustment indicators did not moderate the effects of Facebook usage habits in risks and opportunities. The less psychosocially adjusted youths were those who ran more risks and also made the most of the opportunities. The results are discussed in light of the role of psychological, socio-cultural and developmental factors.info:eu-repo/semantics/publishedVersio

Targeting metabolic reprogramming in acute myeloid leukemia

The cancer metabolic reprogramming allows the maintenance of tumor proliferation, expansion and survival by altering key bioenergetics, biosynthetic and redox functions to meet the higher demands of tumor cells. In addition, several metabolites are also needed to perform signaling functions that further promote tumor growth and progression. These metabolic alterations have been exploited in different cancers, including acute myeloid leukemia, as novel therapeutic strategies both in preclinical models and clinical trials. Here, we review the complexity of acute myeloid leukemia (AML) metabolism and discuss how therapies targeting different aspects of cellular metabolism have demonstrated efficacy and how they provide a therapeutic window that should be explored to target the metabolic requirements of AML cells.This research was funded by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, by the European Regional Development Fund (FEDER), through the Competitiveness Factors Operational Programme (COMPETE), grant number NORTE-01-0145-FEDER-000013 and by the projects POCI-01-0145-FEDER-028159 and POCI-01-0145-FEDER-030782 by FEDER, through the COMPETE, and by National funds, through the Foundation for Science and Technology (FCT)

Ciprofloxacin and carbamazepine adsorption on activated carbons produced from leather residues

Ciprofloxacin and carbamazepine adsorption was studied using an activated carbon produced from leather residues (wet white shavings) and a commercially available activated carbon (Norit ROW 0.8) and the effect of pH level was studied. The activated carbon produced from wet white shavings showed better results due to its higher specific surface area, confirming that leather residues are a viable precursor for the preparation of activated carbons for the adsorption of these chemicals. The effect of pH on the AC adsorption capacity was not significant in the case of carbamazepine, however lower pH led to higher adsorption capacities for ciprofloxacin.info:eu-repo/semantics/publishedVersio

Energetic valorization of algal biomass in a hybrid anaerobic reactor

ABSTRACT: This study evaluated the operation of a hybrid anaerobic reactor fed with algal biomass cultivated in effluent from the brewery industry. Three stages of operation were distinguished during the 72 days of semi-continuous functioning of the reactor: Stage 1 (S1), in which algal biomass was used as substrate; Stage 2 (S2), in which 10% (v/v) of the algal biomass was substituted by olive mill wastewater (OMW); and Stage 3 (S3), in which algal biomass was heat pre-treated. During Sl, a loss of solids was observed, with an increment of organic matter in the outlet. The substitution of 10% of the volume of algal biomass by OMW tripled the methane productivity obtained in the previous stage by digestion of pure algal biomass. Heat pre-treatment was not efficient in rupturing the cell wall, and consequently did not have any effect on the increase in biogas production. The complementarity of substrates in the assessed conditions led to better results than the pre-treatment of the algal biomass.info:eu-repo/semantics/publishedVersio

Para uma interpretação na guitarra das sonatas BMW 1001/1003/1005 de Bach inspirada numa memorabília das práticas interpretativas

Doutoramento em Música - PerformanceO presente trabalho procura compreender as abordagens interpretativas desenvolvidas na guitarra das sonatas para violino BWV 1001, 1003 e 1005 de Bach e apresenta uma proposta de interpretação inspirada no autógrafo original. Sistematiza características de transcrições e gravações das obras no instrumento, e considera as respectivas inferências interpretativas. Face ao significativo número de autores e intérpretes que, adaptando o texto de Bach, privilegiam a faceta harmónica da guitarra e desvalorizam o uso de recursos expressivos da prática interpretativa barroca implícitos e explícitos na notação, problematiza os desafios colocados a uma interpretação num instrumento harmónico que mantém o texto escrito para um outro predominantemente melódico, e faz da articulação o seu centro, facultando propostas de realização. O texto de Bach para violino, as práticas barrocas e o legado dos discursos interpretativos sobre as obras integram o repositório de memórias que inspiraram e fundamentaram a criação de uma interpretação. Nela se tomam opções estéticas e encontram as respectivas soluções de realização técnica na sequência da procura de novos caminhos interpretativos, através da recuperação de alguns aspectos que teriam tido expressão numa imaginária interpretação oitocentista – criando uma outra memória.The present work is an attempt to understand the interpretative approaches developed so far on the guitar of Bach’s violin sonatas BWV 1001, 1003, 1005 and submits a proposal for an interpretation inspired in the original autograph. Characteristics of transcriptions and recordings of the works on the instrument are systematised and the corresponding interpretative inferences considered. Faced with the significant number of authors and interpreters who, while adapting Bach’s text, attach the most value to the harmonic quality of the guitar and underestimate the use of expressive resources of the baroque interpretative praxis implicit and explicit in Bach’s notation, the present work confronts the challenges raised by an interpretation on a harmonic instrument which maintains the original text written for a predominantly melodic one, and focuses primarily on articulation, providing answers for its realization. Bach’s text for violin, baroque practices and the legacy of interpretative discourses about the works themselves integrate the memoribilia inspiring and supporting the creation of an interpretation. As a result of the search for new interpretative paths, aesthetic options are made and technical solutions found, by recovering aspects which would have found expression in an imaginary XVIII century interpretation – giving birth to another memory