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2015
Seixas, J, Simões S, Dias L, Kanudia A, Fortes P, Gargiulo M.  2015.  Assessing the cost-effectiveness of electric vehicles in European countries using integrated modeling. Energy Policy. 80(May 2015):165-176. AbstractWebsite

Electric vehicles (EVs) are considered alternatives to internal combustion engines due to their energy efficiency and contribution to CO2 mitigation. The adoption of EVs depends on consumer preferences, including cost, social status and driving habits, although it is agreed that current and expected costs play a major role. We use a partial equilibrium model that minimizes total energy system costs to assess whether EVs can be a cost-effective option for the consumers of each EU27 member state up to 2050, focusing on the impact of different vehicle investment costs and CO2 mitigation targets. We found that for an EU-wide greenhouse gas emission reduction cap of 40% and 70% by 2050 vis-à-vis 1990 emissions, battery electric vehicles (BEVs) are cost-effective in the EU only by 2030 and only if their costs are 30% lower than currently expected. At the EU level, vehicle costs and the capability to deliver both short- and long-distance mobility are the main drivers of BEV deployment. Other drivers include each state’s national mobility patterns and the cost-effectiveness of alternative mitigation options, both in the transport sector, such as plug-in hybrid electric vehicles (PHEVs) or biofuels, and in other sectors, such as renewable electricity.

Fernandes, CSM, Gonçalves B, Sousa M, Martins DL, Barroso T, Pina AS, Peixoto C, Aguiar-Ricardo A, Roque ACA.  2015.  Biobased Monoliths for Adenovirus Purification. ACS Applied Materials & Interfaces. 7(12):6605-6612., Number 12 AbstractWebsite

Adenoviruses are important platforms for vaccine development and vectors for gene therapy, increasing the demand for high titers of purified viral preparations. Monoliths are macroporous supports regarded as ideal for the purification of macromolecular complexes, including viral particles. Although common monoliths are based on synthetic polymers as methacrylates, we explored the potential of biopolymers processed by clean technologies to produce monoliths for adenovirus purification. Such an approach enables the development of disposable and biodegradable matrices for bioprocessing. A total of 20 monoliths were produced from different biopolymers (chitosan, agarose, and dextran), employing two distinct temperatures during the freezing process (−20 °C and −80 °C). The morphological and physical properties of the structures were thoroughly characterized. The monoliths presenting higher robustness and permeability rates were further analyzed for the nonspecific binding of Adenovirus serotype 5 (Ad5) preparations. The matrices presenting lower nonspecific Ad5 binding were further functionalized with quaternary amine anion-exchange ligand glycidyltrimethylammonium chloride hydrochloride by two distinct methods, and their performance toward Ad5 purification was assessed. The monolith composed of chitosan and poly(vinyl) alcohol (50:50) prepared at −80 °C allowed 100% recovery of Ad5 particles bound to the support. This is the first report of the successful purification of adenovirus using monoliths obtained from biopolymers processed by clean technologies.

Mendes, MJ, Morawiec S, Mateus T, Lyubchyk A, Águas H, Ferreira I, Fortunato E, Martins R, Priolo F, Crupi I.  2015.  Broadband light trapping in thin film solar cells with self-organized plasmonic nano-colloids. Nanotechnology. 26(13):135202. AbstractWebsite

The intense light scattered from metal nanoparticles sustaining surface plasmons makes them attractive for light trapping in photovoltaic applications. However, a strong resonant response from nanoparticle ensembles can only be obtained if the particles have monodisperse physical properties. Presently, the chemical synthesis of colloidal nanoparticles is the method that produces the highest monodispersion in geometry and material quality, with the added benefits of being low-temperature, low-cost, easily scalable and of allowing control of the surface coverage of the deposited particles. In this paper, novel plasmonic back-reflector structures were developed using spherical gold colloids with appropriate dimensions for pronounced far-field scattering. The plasmonic back reflectors are incorporated in the rear contact of thin film n-i-p nanocrystalline silicon solar cells to boost their photocurrent generation via optical path length enhancement inside the silicon layer. The quantum efficiency spectra of the devices revealed a remarkable broadband enhancement, resulting from both light scattering from the metal nanoparticles and improved light incoupling caused by the hemispherical corrugations at the cells' front surface formed from the deposition of material over the spherically shaped colloids.

Monteiro, JM, Fernandes PB, Vaz F, Pereira AR, Tavares AC, Ferreira MT, Pereira PM, Veiga H, Kuru E, VanNieuwenhze M, Brun YV, Filipe SR, Pinho MG.  2015.  Cell shape dynamics during the staphylococci cell cycle. Nat. Commun. 6:8055.
Echeverria, C, Almeida PL, Feio G, Figueirinhas JL, Godinho MH.  2015.  A cellulosic liquid crystal pool for cellulose nanocrystals: Structure and molecular dynamics at high shear rates. European Polymer Journal. 72:72-81. AbstractWebsite

Cellulose and its derivatives, such as hydroxypropylcellulose (HPC) have been studied for a long time but they are still not well understood particularly in liquid crystalline solutions. These systems can be at the origin of networks with properties similar to liquid crystalline (LC) elastomers. The films produced from LC solutions can be manipulated by the action of moisture allowing for instance the development of a soft motor (Geng et al., 2013) driven by humidity. Cellulose nanocrystals (CNC), which combine cellulose properties with the specific characteristics of nanoscale materials, have been mainly studied for their potential as a reinforcing agent. Suspensions of CNC can also self-order originating a liquid-crystalline chiral nematic phases. Considering the liquid crystalline features that both LC-HPC and CNC can acquire, we prepared LC-HPC/CNC solutions with different CNC contents (1,2 and 5 wt.%). The effect of the CNC into the LC-HPC matrix was determined by coupling rheology and NMR spectroscopy - Rheo-NMR a technique tailored to analyse orientational order in sheared systems. (C) 2015 Elsevier Ltd. All rights reserved.

Tempera, C, Franco R, Caro C, André V, Eaton P, Burke P, Hänscheid T.  2015.  Characterization and optimization of the haemozoin-like crystal (HLC) assay to determine Hz inhibiting effects of anti-malarial. Malaria Journal. 14:403.
Palma, SI, Carvalho A, Silva J, Martins P, Marciello M, Fernandes AR, Del Puerto Morales M, Roque AC.  2015.  Covalent coupling of gum arabic onto superparamagnetic iron oxide nanoparticles for MRI cell labeling: physicochemical and in vitro characterization. Contrast Media Mol Imaging. 10:320-8., Number 4 AbstractWebsite

Gum arabic (GA) is a hydrophilic composite polysaccharide derived from exudates of Acacia senegal and Acacia seyal trees. It is biocompatible, possesses emulsifying and stabilizing properties and has been explored as coating agent of nanomaterials for biomedical applications, namely magnetic nanoparticles (MNPs). Previous studies focused on the adsorption of GA onto MNPs produced by co-precipitation methods. In this work, MNPs produced by a thermal decomposition method, known to produce uniform particles with better crystalline properties, were used for the covalent coupling of GA through its free amine groups, which increases the stability of the coating layer. The MNPs were produced by thermal decomposition of Fe(acac)3 in organic solvent and, after ligand-exchange with meso-2,3-dimercaptosuccinic acid (DMSA), GA coating was achieved by the establishment of a covalent bond between DMSA and GA moieties. Clusters of several magnetic cores entrapped in a shell of GA were obtained, with good colloidal stability and promising magnetic relaxation properties (r2 /r1 ratio of 350). HCT116 colorectal carcinoma cell line was used for in vitro cytotoxicity evaluation and cell-labeling efficiency studies. We show that, upon administration at the respective IC50 , GA coating enhances MNP cellular uptake by 19 times compared to particles bearing only DMSA moieties. Accordingly, in vitro MR images of cells incubated with increasing concentrations of GA-coated MNP present dose-dependent contrast enhancement. The obtained results suggest that the GA magnetic nanosystem could be used as a MRI contrast agent for cell-labeling applications.

I.C.J.Palma, S, Carvalho A, Silva J, Fernandes AR, del Puerto-Morales M, Roque ACA.  2015.  Covalent coupling of gum arabic onto superparamagnetic iron oxide nanoparticles for MRI cell labeling: physiochemical and in vitro characterization. Contrast Media and Molecular Imaging. AbstractWebsite

Gum arabic (GA) is a hydrophilic composite polysaccharide derived from exudates of Acacia senegal and Acacia seyal trees. It is biocompatible, possesses emulsifying and stabilizing properties and has been explored as coating agent of nanomaterials for biomedical applications, namely magnetic nanoparticles (MNPs). Previous studies focused on the adsorption of GA onto MNPs produced by co-precipitation methods. In this work, MNPs produced by a thermal decomposition method, known to produce uniform particles with better crystalline properties, were used for the covalent coupling of GA through its free amine groups, which increases the stability of the coating layer. The MNPs were produced by thermal decomposition of Fe(acac)3 in organic solvent and, after ligand-exchange with meso-2,3-dimercaptosuccinic acid (DMSA), GA coating was achieved by the establishment of a covalent bond between DMSA and GA moieties. Clusters of several magnetic cores entrapped in a shell of GA were obtained, with good colloidal stability and promising magnetic relaxation properties (r2 /r1 ratio of 350). HCT116 colorectal carcinoma cell line was used for in vitro cytotoxicity evaluation and cell-labeling efficiency studies. We show that, upon administration at the respective IC50 , GA coating enhances MNP cellular uptake by 19 times compared to particles bearing only DMSA moieties. Accordingly, in vitro MR images of cells incubated with increasing concentrations of GA-coated MNP present dose-dependent contrast enhancement. The obtained results suggest that the GA magnetic nanosystem could be used as a MRI contrast agent for cell-labeling applications.

Baptista, AC, Botas A, Almeida A, Nicolau A, Falcão B, Soares M, Leitão JP, Martins R, Borges JP, Ferreira I.  2015.  Down conversion photoluminescence on PVP/Ag-nanoparticles electrospun composite fibers. Optical Materials. 39:278–281. AbstractWebsite

The influence of Ag nanoparticles (Ag NPs) on the luminescence of electrospun nonwoven mats made of polyvinylpyrrolidone (PVP) has been studied in this work. The PVP fibers incorporating 2.1–4.3 nm size Ag NPs show a significant photoluminescence (PL) band between 580 and 640 nm under 325 nm laser excitation. The down conversion luminescence emission is present even after several hours of laser excitation, which denotes the durability and stability of fibers to consecutive excitations. As so these one-dimensional photonic fibers made using cheap methods is of great importance for organic optoelectronic applications, fluorescent clothing or counterfeiting labels.

Baptista, AC, Botas AM, Almeida APC, Nicolau AT, Falcão BP, Soares MJ, Leitão JP, Martins R, Borges JP, Ferreira I.  2015.  Down conversion photoluminescence on PVP/Ag-nanoparticles electrospun composite fibers. Opt. Mater.. 39:278-281. AbstractWebsite

The influence of Ag nanoparticles (Ag NPs) on the luminescence of electrospun nonwoven mats made of polyvinylpyrrolidone (PVP) has been studied in this work. The PVP fibers incorporating 2.1–4.3 nm size Ag NPs show a significant photoluminescence (PL) band between 580 and 640 nm under 325 nm laser excitation. The down conversion luminescence emission is present even after several hours of laser excitation, which denotes the durability and stability of fibers to consecutive excitations. As so these one-dimensional photonic fibers made using cheap methods is of great importance for organic optoelectronic applications, fluorescent clothing or counterfeiting labels.

Muelle, H, Barquinha P, Ferreira I, Fortunato E, Santos MC, Diniz MS.  2015.  Effects of ultra-sonication on the cyanobacteria Microcystis aeruginosa structure and growth. Microsc. Microanal.. 21:50-51. AbstractWebsite

The eutrophication of surface waters caused by cyanobacteria is a worldwide problem, leading to expensive
water treatment costs [1]. In addition, the production of microcystins by these microalgae may cause many
health problems to humans and animals (e.g. liver cancer) and even death [2]. Therefore, a variety of
methods have been developed to control cyanobacteria blooms, including physical and chemical treatments.
However, they have negative impacts on other species of (micro) algae and on other aquatic biota. As a
consequence, ultrasonic algae treatment has been proposed as a clean approach to controlling the blooms of
some algae species and microcystins degradation [3]. Still, the specific effects of ultra-sonication on
cyanobacteria are not well known. The present work aimed to study the effects of ultra-sonication on the
cyanobacteria structure under different ultrasound conditions (changing frequency and power) by using
conventional histology and electron microscopy methods.
Microcystis spp. were harvested in a lake from Azores (Portugal) and stored in the cool and dark until
transported to the laboratory. Cyanobacteria were cultured in liquid BG-11 axenic medium at 22ºC in an
incubator chamber, under continuous illumination (fluorescent cold white light).
Samples were collected and suspensions of cells (1ml each) were subjected to ultrasonic irradiation using
diverse ultrasonic equipment (UP100H; UP200S, sonoreactor UTR 200 and ultrasonic bath) and testing
different exposure times. All the experimental algal suspensions were exposed for 5 min to ultrasonication
(on ice for periods of 10s to avoid heating). After ultrasonication cyanobacteria growth was assessed for a
period of 14 days and structural changes in cells were evaluated by light (LM) and scanning electron
microscopy (SEM) examination. The results show growth inhibition of the cyanobacteria according to
intensity and power used in each ultrasonic device. The use of the most powerful devices (sonoreactor and
UP200S) resulted in a massive disrupting of cell walls with consequent cell death (Fig. 1e,f). Similar results
were obtained by Ahan et al. [1] and Nakano et al. [4] and showing cell wall disruption. However, even
after exposure to the most powerful instrumentation it was possible to detect some viable cells and after 14
days colonies were already visible. The results from light and electron microscopy showed noticeable
changes at the structural level such as disruption of cell gas vacuoles (arrowhead), colony disaggregation and
damage of cell walls of cells (Fig. 1c-f).
As a consequence, the use of ultrasounds to improve water quality from eutrophic waters must be considered
with careful in terms of efficiency and other complementary methods should be considered to assure good
water quality criteria. In addition, the effects of ultrasonication in other aquatic organisms require further
studies before using this technology to control algae blooms.

Poggi, F, Firmino A, Amado MP.  2015.  Energy supply-storage models for Rural Net-Zero Communities – An integrated approach. EMER 2015. :167-172., Madrid: ISBN-10: 1-62734-559-0; ISBN-13: 978-1-62734-559-0
Ito, Y, Tochio T, Fukushima S, Taborda A, Sampaio JM, Marques JP, Parente F, Indelicato P, Santos JP.  2015.  Experimental and theoretical determination of the Kα2/Kα1 intensity ratio for zinc. Journal of Quantitative Spectroscopy and Radiative Transfer. 151:295-299. AbstractWebsite

X-ray intensity ratios, such as the Kα2/Kα1 ratio, are parameters with a large application in atomic physics and related scientific and technological areas. D.

Vinhas, R, Cordeiro M, Carlos FF, Mendo S, Fernandes AR, Figueiredo S, Baptista PV.  2015.  Gold nanoparticle-based theranostics: disease diagnostic and treatment using a single nanomaterial. J. Nanobiosensors in Disease Diagnosis. 11-23(4) AbstractWebsite

Nanotheranostics takes advantage of nanotechnology-based systems in order to diagnose and treat a specific disease. This approach is particularly relevant for personalized medicine, allowing the detection of a disease at an early stage, to direct a suitable therapy toward the target tissue based on the molecular profile of the altered phenotype, subsequently facilitating disease monitoring and following treatment. A tailored strategy also enables to reduce the off-target effects associated with universal treatments and improve the safety profile of a given treatment. The unique optical properties of gold nanoparticles, their ease of surface modification, and high surface-to-volume ratio have made them central players in this area. By combining imaging, targeting, and therapeutic agents in a single vehicle, these nanoconjugates are (ought to be) an important tool in the clinics. In this review, the multifunctionality of gold nanoparticles as theranostics agents will be highlighted, as well as the requirements before the translation of these nanoplatforms into routine clinical practice.

Franco, R, Pedrosa P, Carlos FF, Veigas B, Baptista PV.  2015.  Gold Nanoparticles for DNA/RNA based diagnostics. Handbook of Nanoparticles. :1339-1364., Zurich: Springer International Publishing Switzerland
Martins, P, Jesus J, Santos S, Raposo LR, Roma-Rodrigues C, Baptista PV, Fernandes AR.  2015.  Heterocyclic Anticancer Compounds: Recent Advances and the Paradigm Shift towards the Use of Nanomedicine’s Tool Box. Molecules. 9(20):16852-16891. AbstractWebsite

The majority of heterocycle compounds and typically common heterocycle fragments present in most pharmaceuticals currently marketed, alongside with their intrinsic versatility and unique physicochemical properties, have poised them as true cornerstones of medicinal chemistry. Apart from the already marketed drugs, there are many other being investigated for their promising activity against several malignancies. In particular, anticancer research has been capitalizing on the intrinsic versatility and dynamic core scaffold of these compounds. Nevertheless, as for any other promising anticancer drugs, heterocyclic compounds do not come without shortcomings. In this review, we provide for a concise overview of heterocyclic active compounds and families and their main applications in medicine. We shall focus on those suitable for cancer therapy while simultaneously addressing main biochemical modes of action, biological targets, structure-activity relationships as well as intrinsic limitation issues in the use of these compounds. Finally, considering the advent of nanotechnology for effective selective targeting of drugs, we shall discuss fundamental aspects and considerations on nanovectorization of such compounds that may improve pharmacokinetic/pharmacodynamic properties of heterocycles.

Loureiro, J, Mateus T, Filonovich S, Ferreira M, Figueira J, Rodrigues A, Donovan BF, Hopkins PE, Ferreira I.  2015.  Hydrogenated nanocrystalline silicon thin films with promising thermoelectric properties. Appl. Phys. A. 120(4):1497–1502. AbstractWebsite

The search for materials with suitable thermoelectric properties that are environmentally friendly and abundant led us to investigate p- and n-type hydrogenated nanocrystalline silicon (nc-Si:H) thin films, produced by plasma-enhanced chemical vapor deposition. The Seebeck coefficient and power factor were measured at room temperature showing optimized values of 512 µV K−1 and 3.6 × 10−5 W m−1 K−2, for p-type, and −188 µV K−1 and 2.2 × 10−4 W m−1 K−2, for n-type thin films. The thermoelectric output power of one nc-Si:H pair of both n- and p-type materials is ~91 µW per material cm3, for a thermal gradient of 8 K. The output voltage and current values show a linear dependence with the number of pairs interconnected in series and/or parallel and show good integration performance.

Roma-Rodrigues, C, Barroco C, Raposo LR, Costa MN, Fortunato E, Baptista PV, Fernandes AR, Santos-Sanches I.  2015.  Infection of human keratinocytes by Streptococcus dysgalactiae subspecies dysgalactiae isolated from milk of the bovine udder.. Microbes and Infection. 4(18):290-3. AbstractWebsite

Streptococcus dysgalactiae subsp. dysgalactiae (SDSD) are considered exclusive animal pathogens; however, a putative zoonotic upper limb cellulitis, a prosthetic joint infection and an infective endocarditis were described in humans. To unravel if bovine SDSD isolates are able to infect human cells, the adherence and internalization to human primary keratinocytes of two bovine SDSD strains isolated from milk collected from udder were analyzed. Bacterial adhesion assays and confocal microscopy indicate a high adherence and internalization of SDSD isolates to human cells, suggesting for the first time the ability of bovine isolates to infect human cells.

Coimbra, J, Mota C, Santos S, Baptista PV, Fernandes AR.  2015.  Inorganic Compounds Going NANO. Annals of Medicinal Chemistry and Research. 2(1)medicinalchemistry-1-1010.pdf
Moniz, AB.  2015.  Intuitive Interaction Between Humans and Robots in Work Functions at Industrial Environments: The Role of Social Robotics. Social Robots from a Human Perspective. (Vincent, Jane, Taipale, Sakari, Sapio, Bartolomeo, Lugano, Giuseppe, Fortunati, Leopoldina, Eds.).:67-76., Heidelberg: Springer
Carvalho, F, Atilano ML, Pombinho R, Covas G, Gallo RL, Filipe SR, Sousa S, Cabanes D.  2015.  L-Rhamnosylation of Listeria monocytogenes wall teichoic acids promotes resistance to antimicrobial peptides by delaying interaction with the membrane. PLoS Pathogens. 11:e1004919.
Fortes, P, Alvarenga A, Seixas J, Rodrigues S.  2015.  Long term energy scenarios: Bridging the gap between socio-economic storylines and energy Modeling. Technological Forecasting & Social Change. 91:161-178.Website
Roma-Rodrigues, C, Raposo LR, Fernandes AR.  2015.  microRNAs based therapy of Hypertrophic cardiomyopathy: the road traveled so far. BioMed Research International. :983290. AbstractWebsite

Hypertrophic cardiomyopathy (HCM) is an autosomal dominant disease characterized by variable expressivity, age penetrance, and a high heterogeneity. The transcriptional profile (miRNAs, mRNAs), epigenetic modifications, and posttranslational modifications seem to be highly relevant for the onset of the disease. miRNAs, small noncoding RNAs with 22 nucleotides, have been implicated in the regulation of cardiomyocyte function, being differentially expressed in several heart diseases, including HCM. Moreover, a different miRNA expression profile in the various stages of HCM development is also observed. This review summarizes the current knowledge of the profile of miRNAs characteristic of asymptomatic to overt HCM patients, discussing alongside their potential use for diagnosis and therapy. Indeed, the stability and specificity of miRNAs make them suitable targets for use as biomarkers for diagnosis and prognosis and as therapeutical targets.

Pina, AS, Dias AMGC, Ustok FI, Khoury GE, Fernandes CSM, Branco RJF, Lowe CR, Roque ACA.  2015.  Mild and cost-effective green fluorescent protein purification employing small synthetic ligands. Journal of Chromatography A. 1418:83-93. AbstractWebsite

Abstract The green fluorescent protein (GFP) is a useful indicator in a broad range of applications including cell biology, gene expression and biosensing. However, its full potential is hampered by the lack of a selective, mild and low-cost purification scheme. In order to address this demand, a novel adsorbent was developed as a generic platform for the purification of \{GFP\} or \{GFP\} fusion proteins, giving \{GFP\} a dual function as reporter and purification tag. After screening a solid-phase combinatorial library of small synthetic ligands based on the Ugi-reaction, the lead ligand (A4C7) selectively recovered \{GFP\} with 94% yield and 94% purity under mild conditions and directly from Escherichia coli extracts. Adsorbents containing the ligand \{A4C7\} maintained the selectivity to recover other proteins fused to GFP. The performance of \{A4C7\} adsorbents was compared with two commercially available methods (immunoprecipitation and hydrophobic interaction chromatography), confirming the new adsorbent as a low-cost viable alternative for \{GFP\} purification.

Poggi, F, Firmino A, Amado MP.  2015.  Moving Forward on Sustainable Energy Transitions: The Smart Rural. European Journal of Sustainable Development - DOI:10.14207/ejsd.2015.v4n2p43. 4(2):43-50.