Electrical properties of AlNxOy thin films prepared by reactive magnetron sputtering

Direct current magnetron sputtering was used to produce AlNxOy thin films, using an aluminum target, argon and a mixture of N2+O2 (17:3) as reactive gases. The partial pressure of the reactive gas mixture was increased, maintaining the discharge current constant. Within the two identified regimes of the target (metallic and compound), four different tendencies for the deposition rate were found and a morphological evolution from columnar towards cauliflower-type, ending up as dense and featureless-type films. The structure was found to be Al-type (face centered cubic) and the structural characterization carried out by X-ray 2 diffraction and transmission electron microscopy suggested the formation of an aluminumbased polycrystalline phase dispersed in an amorphous aluminum oxide/nitride (or oxynitride) matrix. This type of structure, composition, morphology and grain size, were found to be strongly correlated with the electrical response of the films, which showed a gradual transition between metallic-like responses towards semiconducting and even insulating-type behaviors. A group of films with high aluminum content revealed a sharp decrease of the temperature coefficient of resistance (TCR) as the concentration ratio of non-metallic/aluminum atomic ratio increased. Another group of samples, where the non-metallic content became more important, revealed a smooth transition between positive and negative values of TCR. In order to test whether the oxynitride films have a unique behavior or simply a transition between the typical responses of aluminum and of those of the correspondent nitride and oxide, the electrical properties of the ternary oxynitride system were compared with AlNx and AlOy systems, prepared in similar conditions.This research is sponsored by FEDER funds through the program COMPETE-Programa Operacional Factores de Competitividade, by the national funds through FCT-Fundação para a Ciência e a Tecnologia, under the project PTDC/CTM-NAN/112574/2009 and Programa Pessoa 2010/2011 Cooperação Portugal/França, Proc.º 441.00, Project“COLOURCLUSTER”. J. Borges also acknowledges FCT financial support under PhD grant no. SFRH/BD/47118/2008

Presence of Gardnerella vaginalis in healthy portuguese women: a pilot study

Bacterial vaginosis (BV) has an important position worldwide, as the leading vaginal disorder in women, and affects 30-50% of African women and 10-20% of White women of reproductive age. This condition although not mortal causes great discomfort and may lead to other complications such as pre-term labour or increase susceptibility for HIV infection. During BV occur a decrease of Lactobacillus spp. present in the vaginal epithelium and an increase in the number of anaerobic microorganisms like Gardnerella vaginalis, Pretovella spp., Mobilincus spp.; Mycoplasma hominis and Atopobium vaginae. Gardnerella vaginalis is also responsible for the formation of a biofilm in the vaginal epithelium in sick women’s. However, the direct correlation between the pathology and the causing agent (or agents) has not been clearly established. Currently there is only one article in PubMed (Guerreiro et. al, 1998) referring to the prevalence of bacterial vaginosis in Portugal and we aim to extend the research in this field specifically to the portuguese population. As part of this effort one of our aims it to characterise the bacterial population of portuguese women both healthy and diagnosed with BV. As such we collected swab samples of vaginal fluids from protuguese women with the help of health professionals and using self collection. The swabs were collected and treated within 24 hours at the University of Minho for the characterization of the bacterial population present, by using conventional microbiological growth techniques, PNA-FISH microscopy and 16S PCR. It was found that about 20% of the samples tested possessed G. vaginalis and all possessed Lactobacillus spp. using all 3 identification techniques described. This result is consistent with previous reports of G. vaginalis prevalence althought slightly lower, and shows that traditional microbiological techniques, microscopy and molecular methods were consistent in terms of results

Sustained remission from depressive-like behavior depends on hippocampal neurogenesis

Impairment of hippocampal neurogenesis has been associated with the expression of depressive-like symptoms and some studies have suggested neurogenesis as a critical factor in the normalization of behavior by antidepressant (AD) drugs. This study provides robust evidence that ongoing neurogenesis is essential for the maintenance of behavioral homeostasis and that its pharmacological arrest precipitates symptoms commonly found in depressed patients. Further, the incorporation of newly born neurons and astrocytes into the preexisting hippocampal neurocircuitry is shown to be necessary for the spontaneous recovery from the adverse effects of stress and for long-term benefits of AD treatments.We thank M Carneiro and L Martins for technical assistance. AM-P, LP, MM and SM received fellowships from the Portuguese Foundation for Science and Technology (FCT). This work was supported by FCT (PTDC/SAU-NEU/105180/2008) and the ICVS

Solid Waste Mixtures as Constructed Wetlands Filling: Effect of Hydraulic Loading Rate on Nutrient Removal from Wastewater

This study aims to contribute to constructed wetlands’ (CWs) eco-efficiency by applying the concepts of circular economy and waste to treat waste. Five sets of lab-scale CWs with different combinations of filling materials were evaluated and the effect of the hydraulic loading rate (HLR) on the nutrient removal efficiencies was studied. Each CW set consisted of two, duplicate, plastic pots with solid waste filling supporting Phragmites australis macrophyte plants. The filling materials were layer combinations of limestone rock fragments, a waste from construction activities, and one of four other solid wastes: cork granulates from the cork industry (LCG); snail shells from the food and catering industry (LSS); coal slag from coal power plants (LCS); and clay brick fragments from construction activities (LBF). A reference set (LO) was filled only with limestone fragments. The CWs were operated using a low-strength wastewater in successive fill-and-drain cycles with a retention time of one to eight days and a one-day rest. Their removal efficiency was evaluated for COD, total phosphorus (TP) and total nitrogen (TN). All four CWs with mixed filling showed COD removal efficiencies higher than the reference CW and above 79%. The highest removal efficiency was achieved by the LCS CW (91 to 97%). The reference LO CW showed the highest TP removal efficiency. With exception of the LSS CW, the mixed filling CWs showed removal efficiencies close to the reference CW (above 55%). All but the LSS CW showed higher TN removal efficiencies than the reference CW (above 51%). The observed effect of HLR depends on the type of CW. The effect on COD, TP and TN removal efficiencies averaged 9%, 15% and 20%, respectively, for a range of HLR from 0.005 to 0.087 m/day. From this study it can be concluded that all tested layer-packed mixed solid waste fillings are adequate substrate combinations for nutrient removal from wastewater. Moreover, high nutrient removal efficiencies were maintained over a wide range of hydraulic loading rates. This innovative combination of waste materials can improve the CW adaptability to specific types of wastewater and contribute to reducing solid waste disposal in landfills.This work was supported by Program FEDER, ref. POCI-01-0145-FEDER-023314, project VALORBIO. The authors acknowledge the collaboration of the Lab.IPT staff and the assistance of the Instituto Politécnico de Tomar maintenance staff.info:eu-repo/semantics/publishedVersio

Combination of various solid wastes with fragmented limestone as filler for constructed wetlands used for wastewater treatment

This study aims to contribute to the development of eco-efficient constructed wetlands through the concept of circular economy and the use of waste to treat waste Combinations of five solid wastes were evaluated as filler materials for CWs used for wastewater treatment To evaluate the combined capability of the waste materials to wastewater treatment, five sets of unplanted lab-scale CWs were established The CWs were operated in a discontinuous mode for three successive fill and drain cycles The highest COD removal rate was obtained for a CW filled with limestone and cork waste 90.3+/-0.9%. The highest total nitrogen removal rate was obtained for a CW filled with limestone and clay brick fragments 84.8+/-0.1%. Total phosphorus removal percentage of 91.8+/-0.1% was achieved for a control CW filled with limestone It was observed that layer packed solid waste combination fillings are adequate in improving COD removal in limestone based CWs, and that all but the limestone snail shells filling have a very good performance for total nitrogen and total phosphorus removal from wastewater.info:eu-repo/semantics/publishedVersio

Tracer experiments with lithium chloride to evaluate the hydrodynamics of constructed wetlands. Comparison of alternative analytical methods

The characterization of water flow dynamics (hydrodynamics) through constructed wetlands is relevant for optimizing wastewater treatment. Although constructed wetlands consist of simple systems, the water flow is complex and irregular, therefore, the study of hydrodynamics requires the use of experimental technics such as tracer experiments. To evaluate the effects of the use of three different analytical methods to compute the concentration of lithium chloride on the main hydrodynamics parameters, tracer experiments were conducted in ten independent lab-scale constructed wetlands. The concentration of lithium chloride in the output flow of the wetlands was calculated by flame photometry, electrical conductivity using a calibration curve and electrical conductivity using the salt molar conductivity. The paired samples T-test or the non-parametric Wilcoxon’s Signed-Ranks test were used to demonstrate that the computed hydraulic retention time and the number of tanks accordingly with the tanks-in-series model were not significantly affected by the selected analytical method.This work has been financially supported by FEDER grant COMPETE-01-0145-023342 to project VALORBIO. Authors acknowledge the support of BIOTEC.ipt and Lab.IPT and the work of Carlos Ferreira, Isabel Silva and Alcino Serras.info:eu-repo/semantics/publishedVersio

Analysis of a collaborative scheduling model applied in a job shop manufacturing environment

Collaborative Manufacturing Scheduling (CMS) is not yet a properly explored decision making practice, although its potential for being currently explored, in the digital era, by combining efforts among a set of entities, either persons or machines, to jointly cooperate for solving some more or less complex scheduling problem, namely occurring in job shop manufacturing environments. In this paper, an interoperable scheduling system integrating a proposed scheduling model, along with varying kinds of solving algorithms, are put forward and analyzed through an industrial case study. The case study was decomposed in three application scenarios, for enabling the evaluation of the proposed scheduling model when envisioning the prioritization of internal–makespan-or external–number of tardy jobs-performance measures, along with a third scenario assigning a same importance or weight to both kinds of performance measures. The results obtained enabled us to realize that the weighted application scenario permitted reaching more balanced, thus a potentially more attractive global solution for the scheduling problem considered through the combination of different kinds of scheduling algorithms for the resolution of each underlying sub problem according to the proposed scheduling model. Besides, the decomposition of a global more complex scheduling problem into simpler sub-problems turns them easier to be solved through the different solving algorithms available, while further enabling to obtain a wider range of alternative schedules to be explored and evaluated. Thus, contributing to enriching the scheduling problem-solving process. A future exploration of the application in other types of manufacturing environments, namely occurring in the context of extended, networked, distributed or virtual production systems, integrating an increased and variable set of collaborating entities or factories, is also suggested.The project is funded by the FCT—Fundação para a Ciência e Tecnologia through the R&D Units Project Scope: UIDB/00319/2020, and EXPL/EME-SIS/1224/2021

Biocompatible polymeric microparticles produced by a simple biomimetic approach

The use of superhydrophobic surfaces to produce polymeric particles proves to be biologically friendly since it entails the pipetting and subsequent cross-linking of polymeric solutions under mild experimental conditions. Moreover, it renders encapsulation efficiencies of ∼100%. However, the obtained particles are 1 to 2 mm in size, hindering to a large extent their application in clinical trials. Improving on this technique, we propose the fabrication of polymeric microparticles by spraying a hydrogel precursor over superhydrophobic surfaces followed by photo-cross-linking. The particles were produced from methacrylamide chitosan (MA-CH) and characterized in terms of their size and morphology. As demonstrated by optical and fluorescence microscopy, spraying followed by photo-cross-linking led, for the first time, to the production of spherical particles with diameters on the order of micrometers, nominal sizes not attainable by pipetting. Particles such as these are suitable for medical applications such as drug delivery and tissue engineering.We thank Ivo Aroso and Ana Isabel Neto for their valuable support with FTIR and compression experiments, respectively. A.M.S.C. thanks FCT for financial support through grant BIM/PTDC/CTM-BPC/112774/2009_02. M.A.-M. thanks CONACyT (Mexico) for financial support through post-doc grant no. 203732. N.M.O. thanks FCT for financial support through Ph.D. scholarship no. SFRH/BD/73172/2010. This work was funded by the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement no. REGPOT-CT2012-316331-POLARIS, by FEDER through the Competitive Factors Operation Program-COMPETE, and by national funds through FCT - Fundacao para a Ciencia e a Tecnologia in the scope of project PTDC/CTM-BIO/1814/2012

Chronic stress targets adult neurogenesis preferentially in the suprapyramidal blade of the rat dorsal dentate gyrus

First Online: 29 August 2017The continuous generation of new neurons and glial cells in the adult hippocampal dentate gyrus (DG) represents an important form of adult neuroplasticity, involved in normal brain function and behavior but also associated with the etiopathogenesis and treatment of psychiatric disorders. Despite the large number of studies addressing cell genesis along the septotemporal axis, data on the anatomical gradients of cytogenesis along the DG transverse axis is scarce, especially after exposure to stress. As such, in this study we characterized both basal proliferation and survival of adult-born neural cells along the transverse axis of the rat dorsal DG, and after stress exposure. In basal conditions, both proliferating cells and newborn neurons and glial cells were preferentially located at the subgranular zone and suprapyramidal blade. Exposure to chronic stress induced an overall decrease in the generation of adult-born neural cells and, more specifically, produced a regional-specific decrease in the survival of adult-born neurons at the suprapyramidal blade. No particular region-specific alterations were observed on surviving adult-born glial cells. This work reveals, for the first time, a distinct survival profile of adult-born neural cells, neurons and glial cells, among the transverse axis of the DG, in both basal and stress conditions. Our results unveil that adult-born neurons are preferentially located in the suprapyramidal blade and suggest a regional-specific impact of chronic stress in this blade with potential repercussions for its functional significance.NDA, PP, AMP, ARMS, MM and LP received fellowships from the Portuguese Foundation for Science and Technology (FCT). This work was funded by FCT (IF/01079/2014). This article has been 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). This work has been funded by FEDER funds, through the Competitiveness Factors Operational Programme (COMPETE), and by National funds, through the Foundation for Science and Technology (FCT), under the scope of the project POCI-01-0145-FEDER-007038.info:eu-repo/semantics/publishedVersio

Design of alumina monoliths by emulsion-gel casting: understanding the monolith structure from a rheological approach

Multimodal porous cellular alumina structures (monoliths) were prepared by an emulsion-gel casting technique using eco-friendly and inexpensive lipids such as corn oil, castor oil, margarine and their mixtures as the dispersed phase. The monoliths obtained showed good mechanical stability, exhibiting compressive strengths in the range of 8–50 N·mm−2. Mercury intrusion porosimetry analysis showed that the monoliths produced presented porosities ranging from 28% to 60% and average pore sizes within 0.2–3.2 μm. The formation of the porous networks was interpreted based on combined droplet coalescence, flocculation and Ostwald ripening effects. The presence of such effects along the emulsion storage time led to changes in their viscoelastic and morphological properties, which were found to correlate with structural descriptors of monoliths after sintering (e.g. average pore sizes and porosity). These correlations open up the possibility to anticipate the final structure of the monoliths and adjust emulsion-gel conditions to produce customized cellular structures with fine-tuned porosities and pore sizes, envisaging their application in membrane processes or chromatography.publishe