Caracterização do comportamento à fadiga da conexão aço-betão em elementos mistos

No presente trabalho, procura-se avaliar o comportamento de conectores de tipo perno inseridos em lajes maciças de betão leve de elevada resistência e sujeitos a carregamentos cícli-cos. O estudo realizado é de carácter experimental e tem como objectivo geral avaliar e caracterizar o comportamento à fadiga da conexão entre aço e betão leve em elementos mistos. No desenvolvimento deste estudo fabricaram-se 2 provetes de tipo push-out (definido a partir da NP EN 1994-1 [1]) que foram ensaiados sob carregamento monotónico com controlo de deformação e 12 provetes de tipo push-out, que foram ensaiados sob ciclos de carga e descarga de várias amplitudes

Caracterização do comportamento de conectores tipo perno sob diferentes tipos de carregamento

No presente trabalho procura-se avaliar o comportamento de conectores tipo perno inseridos em lajes de betão leve de elevada resistência e sujeitos a carregamentos monotónicos e cíclicos. O estudo realizado é de carácter experimental, tendo-se fabricado provetes de tipo push-out. Um grupo destes provetes foi ensaiado sob carregamento monotónico com controlo de deformação e outro grupo foi ensaiado sob carregamento composto por ciclos de carga e descarga de várias amplitudes. O trabalho experimental foi realizado no Laboratório de Estruturas de Engª Civil da Universidade do Minho (LEST-UM)

The Portuguese version of the body investment scale: psychometric properties and relationships with disordered eating and emotion dysregulation

Background This study aimed to examine the psychometric properties of the Portuguese version of the Body Investment Scale (BIS) in a nonclinical sample of students and a clinical sample of outpatients with eating disorders, to analyse the differences in the BIS factors between the samples and to explore the relationships among body investment, eating disorder symptoms and difficulties in emotion regulation. Methods The clinical (n = 93) and nonclinical (n = 448) samples completed self-report measures. Results In contrast to the nonclinical sample, confirmatory factor analysis showed an acceptable fit for the original four-factor solution of the BIS in the clinical sample. This scale also demonstrated adequate internal consistency in both samples. Significant differences in BIS factors were found between the samples; outpatients with eating disorders presented more negative feelings about the body, less comfort with touch and lower levels of body protection than those of the students. In the clinical sample, significant relationships were found between these factors and a higher severity of disordered eating, as well as between these factors and higher difficulties in emotion regulation. Conclusions The Portuguese version of the BIS is a psychometrically sound measure for the assessment of body investment, and it is especially appropriate in a clinical setting of outpatients with eating disorders.- This work was supported by the Foundation for Science and Technology under Grant [SFRH/BD/116974/2016]

Antibiotic resistance in wastewater: Occurrence and fate ofEnterobacteriaceaeproducers of Class A and Class C β-lactamases

Antibiotics have been intensively used over the last decades in human and animal therapy and livestock, resulting in serious environmental and public health problems, namely due to the antibiotic residues concentration in wastewaters and to the development of antibiotic-resistant bacteria. This study aimed to access the contribution of some anthropological activities, namely urban household, hospital and a wastewater treatment plant, to the spread of antibiotic resistances in the treated wastewater released into the Mondego River, Coimbra, Portugal. Six sampling sites were selected in the wastewater network and in the river. The ampicillin-resistant Enterobacteriaceae of the water samples were enumerated, isolated and phenotypically characterized in relation to their resistance profile to 13 antibiotics. Some isolates were identified into species level and investigated for the presence of class A and class C -lactamases. Results revealed high frequency of resistance to the -lactam group, cefoxitin (53.5%), amoxicillin/clavulanic acid combination (43.5%), cefotaxime (22.7%), aztreonam (21.3) cefpirome (19.2%), ceftazidime (16.2%) and to the non--lactam group, trimethoprim/sulfamethoxazol (21.1%), tetracycline (18.2%), followed by ciprofloxacin (14.1%). The hospital effluent showed the higher rates of resistance to all antibiotic, except two (chloramphenicol and gentamicin). Similarly, higher resistance rates were detected in the wastewater treatment plant (WWTP) effluent compared with the untreated affluent. Regarding the multidrug resistance, the highest incidence was recorded in the hospital sewage and the lowest in the urban waste. The majority of the isolates altogether are potentially extended-spectrum -lactamases positive (ESBL(+)) (51.9%), followed by AmpC(+) (44.4%) and ESBL(+)/AmpC(+) (35.2%). The most prevalent genes among the potential ESBL producers were blaOXA (33.3%), blaTEM (24.1%) and blaCTX-M (5.6%) and among the AmpC producers were blaEBC (38.9%), blaFOX (1.9%) and blaCIT (1.9%). In conclusion, the hospital and the WWTP activities revealed to have the highest contribution to the spread of multidrug resistant bacteria in the study area. Such data is important for future management of the environmental and public health risk of these contaminants. This is the first embracing study in the water network of Coimbra region on the dissemination of antibiotic resistance determinants. Moreover, it is also the first report with the simultaneous detection of multiresistant bacteria producers of AmpC and ESBLs -lactamases in aquatic systems in Portugal.info:eu-repo/semantics/publishedVersio

Water-in-oil-in-water double emulsions as protective carriers for Sambucus nigra l. coloring systems

The use of natural colorants is needed to overcome consumer concerns regarding synthetic food colorants0 safety. However, natural pigments have, in general, poor stability against environmental stresses such as temperature, ionic strength, moisture, light, and pH, among others. In this work, water-in-oil-in-water (W1/O/W2) emulsions were used as protective carriers to improve color stability of a hydrophilic Sambucus nigra L. extract against pH changes. The chemical system comprised water and corn oil as the aqueous and oil phases, respectively, and polyglycerol polyricinoleate (PGPR), Tween 80, and gum Arabic as stabilizers. The primary emulsion was prepared using aW1/O ratio of 40/60 (v/v). For the secondary emulsion,W1/O/W2, different (W1/O)/W2 ratios were tested with the 50/50 (v/v) formulation presenting the best stability, being selected as the coloring system to test in food matrices of different pH: natural yogurt (pH 4.65), rice drink (pH 6.01), cow milk (pH 6.47), and soy drink (pH 7.92). Compared to the direct use of the extract, the double emulsion solution gave rise to higher color stability with pH change and storage time, as corroborated by visual and statistical analysis.FCT/MCTES for financial support to CIMO (UIDB/00690/2020). National funding by FCTFoundation for Science and Technology, through the institutional scientific employment programcontract of A. Fernandes, I. Fernandes, and L. Barros. Valor Natural project (Project Norte-01-0247- FEDER-024479).info:eu-repo/semantics/publishedVersio

Infectious risk of elderly patients on peritoneal dialysis: Experience of a portuguese center

Background: The goal of this study was to compare the risk of peritoneal dialysis‑related infections in younger and older patients and to identify risk factors for infection in elderly patients. Methods: We performed a longitudinal retrospective study on a population of Portuguese peritoneal dialysis patients treated at the same center between January 2005 and December 2015. Clinical and laboratory data were collected from medical reports. Two groups of patients were compared: non elderly (< 65 years) and elderly (≥ 65 years). Results: Among 100 patients, there were 73 non elderly (median age 52 years) and 27 elderly (median age 74 years). Elderly patients were not associated with higher PD‑infection rates or with less time to PD‑related infections. Cerebrovascular disease was the only significant adverse predictor of peritonitis in elderly (crude HR 3.8; 95% CI 1.10 to 13.34; P = 0.035) and those with higher levels of serum albumin were less likely to develop peritonitis (crude HR 0.47 per each g/dl of increase; 95% CI 0.24 to 0.89; P = 0.023). Conclusions: In our study, elderly patients did not present a greater risk for peritonitis or catheter‑related infections.info:eu-repo/semantics/publishedVersio

New developments in the forecasting of monthly overnight stays in the North Region of Portugal

The Tourism sector is of strategic importance to the North Region of Portugal and is growing. Forecasting monthly overnight stays in this region is, therefore, a relevant problem. In this paper, we analyze data more recent than those considered in previous studies and use them to develop and compare several forecasting models and methods. We conclude that the best results are achieved by models based on a non-parametric approach not considered so far for these data, the singular spectrum analysis.publishe

Chitosan-cellulose particles as delivery vehicles for limonene fragrance

This study proposes the use of chitosan-cellulose particles to encapsulate limonene, a fragrant component widely used in the flavor and fragrance industries. As cellulose possesses a stiff molecular structure due to the threedimensional arrangement of hydrogen bonded hydroxyls, its dissolution is difficult to achieve. To surpass this constraint, and solubilize cellulose, LiOH/urea/water systems were tested using different freezing temperatures and number of freezing/thawing/stirring cycles. Then, chitosan-cellulose composite particles were produced and characterized by Scanning Electron Microscopy (SEM) to assess morphology and size, and by Fourier Transform Infrared Spectroscopy (FTIR) and Thermogravimetric Analysis (TGA) to access chitosan-cellulose molecular interactions. The release behaviour of limonene from the chitosan-cellulose particles was studied by gas chromatography (GC). The obtained particles presented an average diameter ranging from 1 to 2mm and spherical shape, characteristics very similar to the corresponding empty cellulose-chitosan composite particles. A good affinity was found between the two biopolymers, cellulose and chitosan. The achieved encapsulation efficiency of limonene was 51.29%, and the produced particles demonstrated a burst release of limonene in the first 24 h, followed by a decrease over 162 h. Based on the achieved results this system seems favourable for applications requiring preservation of sensory qualities and prolonged release of fragrances.This work was financially supported by: Associate Laboratory LSRELCM - UID/EQU/50020/2019 - funded by national funds through FCT/ MCTES (PIDDAC). This work is a result of: Project "AIProcMat@N2020 - Advanced Industrial Processes and Materials for a Sustainable Northern Region of Portugal 2020", with the reference NORTE-01- 0145-FEDER-000006, supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (ERDF); Associate Laboratory LSRE-LCM - UID/EQU/50020/2019 - funded by national funds through FCT/MCTES (PIDDAC). CIMO (UID/ AGR/00690/2019) through FEDER under Program PT2020. P. Costa acknowledges her postdoctoral grant from FCT (SFRH/BPD/93108/ 2013). To the national funding by FCT, P.I., through the institutional scientific employment program-contract for I.P. Fernandes contract.info:eu-repo/semantics/publishedVersio

Fourier transform infrared spectroscopy-chemometric approach as a non-destructive olive cultivar tool for discriminating Portuguese monovarietal olive oils

Four Portuguese monovarietal olive oils (cvs. Cobrançosa, Madural, Santulhana and Verdeal Transmontana) were evaluated, totalizing 24 independent samples. Olive cultivar significantly influenced (P values lt 0.05, one-way ANOVA) the oils’ physicochemical and sensory attributes, fulfilling all oils the legal thresholds for extra-virgin classification. Oils from cv. Verdeal Transmontana had the highest oxidative stability (16.9 ± 1.0 h), whereas cvs. Cobrançosa and Santulhana oils have the highest total phenols content (204 ± 30 and 177 ± 33 mg GAE/kg, respectively). Concerning the sensory attributes, only cv. Santulhana oils fitted fruity greenly oils type, presenting, in general, significantly higher olfactory and gustatory intensities (P values lt 0.05, one-way ANOVA), with a higher number of perceived sensory attributes (e.g., herbaceous sensations), compared to the other monovarietal oils. Free acidity, peroxide value, extinction coefficients, total phenols and oxidative stability allowed the unsupervised differentiation (principal component analysis, PCA) of the four monovarietal oils, and in a less extent, the sensory data. Fourier transform infrared (FTIR) spectroscopy-chemometric procedure was developed based on raw or transformed forms of the recorded spectra. Raw, 1st and 2nd derivative spectra allowed the unsupervised (PCA) and supervised (linear discriminant analysis, LDA) identification of the olive cultivar of the studied oils. In fact, FTIR-LDA models, based on the raw transmittance or on their 1st or 2nd derivatives, recorded at 5, 4 or 3 selected wavenumbers, respectively, allowed to correctly classify all oils (sensitivities greater than 99 ± 7% for the repeated K-fold-CV internal validation). Therefore, FTIR spectroscopy could be used as a fast, reliable, environmentally friendly and non-destructive olive cultivar-classification tool for monovarietal oils.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support by national funds FCT/MCTES to CIMO (UIDB/00690/2020) and Project “Green- Health—Digital strategies in biological assets to improve well-being and promote green health” (Norte-01-0145-FEDER-000042) funded by the European Regional Development Fund under the scope of Norte2020—Programa Operacional Regional do Norte. Nuno Rodrigues and Isabel P. Fernandes thank to National funding by FCT— Foundation for Science and Technology, Pinfo:eu-repo/semantics/publishedVersio

Mushroom-based cosmeceutical ingredients: Microencapsulation and in vitro release profile

[EN]Mushrooms can be used as a source of cosmeceutical ingredients. Agaricus bisporus and Pleurotus ostreatus ethanolic extracts present important bioactive properties, but with some compounds showing easy oxidation and degradation. In the present work, microencapsulation by atomization/coagulation technique was used to protect the extracts. The obtained microspheres were characterised in terms of morphology, particle size distribution and encapsulation efficiency. Microencapsulated extracts were incorporated into a semi-solid base cream and their performance compared with the use of the free forms in terms of bioactivity, and in vitro release using the cosmetic matrix and real time conditions (up to 6 months). The physico-chemical properties (colour and pH) of the developed formulations were also monitored over the same time period. The cosmeceutical formulations containing free extracts displayed bioactivity. For the formulations prepared with the encapsulated forms, the release of the extracts was achieved and anti-tyrosinase and antimicrobial activities were observed, while for the antioxidant activity, the extract release over the time was not sufficient to exert an effect. Overall, the use of mushroom extracts in free or encapsulated forms can be an option in cosmeceutical formulations, and the encapsulated forms can allow a controlled release leading to bioactivity control