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- Desulfurization of diesel by extraction coupled with Mo-catalyzed sulfoxidation in polyethylene glycol-based deep eutectic solventsPublication . Juliao, Diana; Gomes, Ana C.; Pillinger, Martyn; Lopes, Andre D.; Valenca, Rita; Ribeiro, Jorge C.; Goncalves, Isabel S.; Balula, Salete S.Oxidative desulfurization (ODS) is a method of removing sulfur from diesel fuel that has the potential to complement or even replace conventional hydrodesulfurization processes in oil refineries. One of the most promising variants of ODS is extractive and catalytic ODS (ECODS) in which the organic sulfur compounds in the liquid fuel are oxidized and extracted in situ from the oil phase into an extractant phase. In this study, the desulfurizalion of model and real diesel fuel has been performed in ECODS systems employing two different types of deep eutectic solvents (DESs), prepared by combining polyethylene glycol (PEG) as hydrogen bond donor with tetrabutylammonium chloride (TBACl) or choline chloride (ChCl) as hydrogen bond acceptor. The ECODS systems were evaluated with the complexes [MoO2Cl2(DMB)(2)] (1) and [MoO2Cl2(DEO)] (2) (DMB - N,N-dimethylbenzamide, DEO = N,N'-diethyloxamide) as catalysts and 30 wt% H2O2 as oxidant. The effects of different reaction conditions, such as the amount of catalyst, H2O2 and DES, and reaction temperature, were investigated. The combination of complex 1 with the DES ChCl/PEG showed the best performance for the removal of dibenzothiophene, 4-methyldibenzothiophene and 4,6-di methyldibenzothiophene from a high-sulfur (3000 ppm) model diesel, allowing a desulfurization efficiency of 99.6% to be attained at 70 degrees C within 2 h. By applying the optimized model diesel ECODS systems to the treatment of a commercial untreated diesel with a sulfur content of 2300 ppm. 82% of sulfur compounds could be eliminated. These promising results indicate that DESs are a viable alternative to ionic liquids as extraction solvents in ECODS processes. (C) 2020 Elsevier B.V. All rights reserved.
- Galangal, the multipotent super spices: A comprehensive reviewPublication . Das, Gitishree; Patra, Jayanta Kumar; Gonçalves, Sandra; Romano, Anabela; Gutierrez-Grijalva, Erick P.; Heredia, J. Basilio; Das Talukdar, Anupam; Shome, Soumitra; Shin, Han-SeungBackground: Galangal is highly appreciated for its potential applications in food and medicine. In spite of its usage in food and herbal medicine in countries like Indonesia and Thailand, very limited data is accessible about its potential applications in therapeutics and pharmacology. It has been reported to be utilized in herbal medicines for treatment against diseases like hemorrhoids, abnormal menstruation, abdominal discomfort, and inflammation, among others. Scope and approach: The widespread use of galangal in food and traditional medicine has fascinated researchers all over the world looking for its enhanced medicinal capabilities, new bioactive compounds with nutraceutical potentials, and probable uses in medicine and pharmacology. A number of literature search methods like searching the related contents with the keywords such as Alpinia sp., galangal, antiviral, cardiovascular, neuroprotective, bioactive compounds, phytochemicals etc. in the web search engines' such as the Google search, Web of Science, Scopus, PubMed etc. were implemented. Key findings and conclusions: Conversely, there is no recent structured and ample review that summarizes the available data on these issues. In the current review, these topics are addressed in detail along with the investigation of scientific evidence supporting the vast applications of galangal in food and its medicinal properties, such as antiviral, cardiovascular and neuroprotective properties, together with the preclinical and clinical studies with galangal bioactive compounds.
- Evaluation of proximate composition, antioxidant properties, and phylogenetic analysis of two edible seaweedsPublication . Rathinam, Raja; Hemaiswarya, Shanmugam; Sridhar, Sekaran; Alagarsamy, Arun; Ganesan, Venkatesan; Elumalai, Sanniyasi; Carvalho, Isabel S.The present study was evaluated for the proximate composition (moisture, carbohydrate, protein, and lipid contents) of two seaweedsGracilaria corticata(Rhodophyceaen) andHalimeda opuntia(Chlorophycean). Phylogenetic analysis based on the SSU (small subunit) rRNA ascertained their molecular identification. The results showed that the carbohydrate (5.72 +/- 0.05 g/100 g), protein (42.38 +/- 0.08 g/100 g), and total lipids (10.09 +/- 0.06 g/100 g) are elevated inG. corticatawhen compared toH. opuntia. H. opuntiahad a protein content of 3.51 +/- 0.072 g/100 g and higher moisture content (95 +/- 0.45 g/100 g). The methanolic extracts ofG. corticataandH. opuntiawere used to examine the antioxidants (viz. TPC, TFC, DPPH, and FRAP) and antidiabetic (alpha-glucosidase) properties. The antioxidant results of the methanolic extract ofG.corticataexhibited a higher amount of phenolic compounds (13.37 +/- 0.01 mg GAE/g dry wt.) compared toH. opuntia. But in the case of flavonoids,H.opuntiacontained a slightly higher amount of quercetin equivalent 9.56 +/- 0.26 mg/g dry wt. In FRAP,H.opuntiashowed an elevated level (62.02 mg TE/g dry wt). DPPH scavenging activity in the seaweed extracts were recorded in the following order:H.opuntiaandG.corticata. The amino acid content ofH.opuntiawas 0.097 +/- 0.56 (mg/g) and 0.086 +/- 0.42 (mg/g) was recorded inG.corticata. [GRAPHICS.]
- Toxin profile of Ostreopsis cf. ovata from Portuguese continental coast and Selvagens Islands (Madeira, Portugal)Publication . Soliño, Lucia; Garcia-Altares, Maria; Godinho, Lia; Reis Costa, PedroThe toxigenic dinoflagellate Ostreopsis cf. ovata is known to produce a range of palytoxin (PLTX) - related compounds named ovatoxins (OVTX). O. cf. ovata presents a wide variability in toxin production and its toxic profile is strain-specific. Several OVTXs, denominated from -a to -h and -I have been reported from different strains of this benthic microalgae up to now, mainly in Mediterranean isolates. However, less is known about the toxin profile of the strains present in the Atlantic coasts of Europe. In this work, strains of O. cf. ovata isolated from the South coast of Portugal mainland (Algarve) and Selvagens Island (Madeira, Portugal) were cultured and tested for toxicity by hemolytic assay. Toxin profiles were qualitatively elucidated by Liquid Chromatography-High Resolution Mass Spectrometry (LC-HRMS). The strain from Algarve presented lower toxic potency than the strain from Selvagens island (12.3 against 54.8 pg of PLTX equivalents per cell) showing in both cases the characteristic toxin profile of Mediterranean strains. The major component, OVTX-a, was concomitant with OVTX from -b to -g and isobaric PLTX. Regarding the morphological characteristics of these strains, as well as their toxin fingerprint, it is likely they are closely related to strains from Mediterranean coasts. The present study reports for the first time the occurrence of several OVTX congeners and iso-PLTX in O. cf. ovata from Portuguese waters. This study provides valuable information to characterize the risk of OVTXs-related outbreaks in Portugal.
- Genetic diversity of a marine foundation species,Laminaria hyperborea(Gunnerus) Foslie, along the coast of IrelandPublication . Schoenrock, Kathryn M.; O'Connor, Aisha M.; Mauger, Stephane; Valero, Myriam; MACHADO, JOÃO NEIVA; Serrao, Ester; Krueger-Hadfield, Stacy A.Worldwide, kelp populations are stressed by warming, increased storms and other anthropogenic disturbances. Marine population distributions are projected to retreat poleward with climate change if they cannot adapt to changing conditions, which would potentially lead to a regime shift in subtidal habitats. In Northern Europe,Laminaria hyperboreais a subtidal ecosystem engineer whose distribution has shifted over millennia, leaving predicted areas of high genetic diversity from the last glacial maximum (LGM) near its southern distribution limit in the Iberian Peninsula. In Ireland,L. hyperboreastructures communities by supporting diverse faunal assemblages and producing large quantities of organic carbon throughout the year. We investigated the genetic diversity of eight populations, ranging from the southern coast to the north-west of Ireland, using nine microsatellite loci. Diversity was found to be highest in Lough Hyne, a Special Area of Conservation (SAC), near the predicted climate refugium. We found evidence of isolation by distance, with high connectivity between populations that were geographically close, probably driven by short range dispersal ofL. hyperboreapropagules. Genetic diversity (measured as expected heterozygosity and allelic richness) was highest at Lough Hyne, and decreased northwards, as predicted from past range shifts. Expected heterozygosity was highest at Lough Hyne (0.706) and decreased northward, with the lowest value at Bridges of Ross (0.283). Based on these patterns, further fine-scale investigation into population diversity, dispersal and potential resilience in Irish kelp forests are necessary as warming and non-native species are observed more and more frequently.
- Neuromorphic organic devices that specifically discriminate dopamine from Its metabolites by nonspecific interactionsPublication . Giordani, Martina; Sensi, Matteo; Berto, Marcello; Di Lauro, Michele; Bortolotti, Carlo Augusto; Gomes, Henrique Leonel; Zoli, Michele; Zerbetto, Francesco; Fadiga, Luciano; Biscarini, FabioSpecific detection of dopamine (DA) is achieved with organic neuromorphic devices with no specific recognition function in an electrolyte solution. The response to voltage pulses consists of amplitude-depressed current spiking mimicking the short-term plasticity (STP) of synapses. An equivalent circuit hints that the STP timescale of the device arises from the capacitance and resistance of the poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) in series with the electrolyte resistance. Both the capacitance and resistance of PEDOT:PSS change with solution compositions. Dose curves are constructed from the STP timescale for each DA metabolite from pM to mM range of concentrations. The STP response of DA is distinctive from the other metabolites even when differences are by one functional group. Both STP and sensitivity to DA are larger across the patho-physiological range with respect to those to DA metabolites. Density functional theory calculations hint to a stronger hydrogen bond pattern of DA ammonium compared to cationic metabolites. The exponential correlation between STP and the binding energy of DA metabolites interacting with PEDOT:PSS indicates that the slow dynamics of ionic species in and out PEDOT:PSS is the origin of the neuromorphic STP. The sensing framework discriminates differences of nonspecific interactions of few kcal mol(-1), corresponding to one functional group in the molecule.
- On the invariance of certain vanishing subspaces of Morrey spaces with respect to some classical operatorsPublication . Alabalik, Aysegul C.; Almeida, Alexandre; Samko, StefanWe consider subspaces of Morrey spaces defined in terms of various vanishing properties of functions. Such subspaces were recently used to describe the closure of C-0(infinity) (R-n) in Morrey norm. We show that these subspaces are invariant with respect to some classical operators of harmonic analysis, such as the Hardy-Littlewood maximal operator, singular type operators and Hardy operators. We also show that the vanishing properties defining those subspaces are preserved under the action of Riesz potential operators and fractional maximal operators.
- Cortical deafness of following bilateral temporal lobe strokePublication . Silva, Julia; Sousa, Marisa; Mestre, Susana; Nzwalo, Isa; Nzwalo, HipólitoCortical deafness is an extremely rare clinical manifestation that originates mainly from bilateral cortical lesions in the primary auditory cortex. Its main clinical manifestation is the bilateral sudden loss of hearing. Diagnosis is difficulty due to its rarity and similarity with other language and communication disorders, such as Wernicke's aphasia, auditory agnosia or verbal deafness. Herein, we present a case report of a young woman with a sudden bilateral loss of auditory comprehension. Initially, a psychiatric nature of the disorder was considered, but the persistence of the symptoms, lead to the diagnosis of cortical deafness secondary to bilateral ischemic lesions in both temporal lobes. Progressive improvement occurred and three months after the initial manifestations she manifested pure verbal deafness. Cortical deafness usually has a poor functional prognosis, with limited therapeutic options. Rehabilitation and speech therapy is recommended to improve the chance of patients achieving communication skills.
- Método computacional de avaliação do risco sísmico de escolasPublication . Estêvão, João M. C.A avaliação sísmica de um conjunto elevado de escolas é uma tarefa muito complexa. Para facilitar esse trabalho, foi desenvolvido um novo programa informático no contexto do projeto de investigação PERSISTAH. O programa é constituído por um conjunto de módulos independentes (objetos computacionais), mas totalmente interligáveis entre si, como num brinquedo da “LEGO®”. Assim, é possível criar facilmente outros programas, bastando para isso ligar de outra maneira os objetos computacionais já criados. Os diversos módulos estão diretamente associados ao conceito de risco sísmico e o resultado do programa é uma lista ordenada de escolas em função do respetivo nível de segurança sísmica, que pode depois ser exportada automaticamente para o Google Earth®.
- Copper Complexes with 1,10-Phenanthroline Derivatives: Underlying Factors Affecting Their CytotoxicityPublication . Nunes, Patrique; Correia, Isabel; Marques, Fernanda; Matos, Antonio Pedro; dos Santos, Margarida M. C.; Azevedo, Cristina G.; Capelo, Jose-Luis; Santos, Hugo M.; Gama, Sofia; Pinheiro, Teresa; Cavaco, Isabel; Pessoa, Joao CostaThe interpretation of in vitro cytotoxicity data of Cu(II)-1,10-phenanthroline (phen) complexes normally does not take into account the speciation that complexes undergo in cell incubation media and its implications in cellular uptake and mechanisms of action. We synthesize and test the activity of several distinct Cu(II)-phen compounds; up to 24 h of incubation, the cytotoxic activity differs for the Cu complexes and the corresponding free ligands, but for longer incubation times (e.g., 72 h), all compounds display similar activity. Combining the use of several spectroscopic, spectrometric, and electrochemical techniques, the speciation of Cu-phen compounds in cell incubation media is evaluated, indicating that the originally added complex almost totally decomposed and that Cu(II) and phen are mainly bound to bovine serum albumin. Several methods are used to disclose relationships between structure, activity, speciation in incubation media, cellular uptake, distribution of Cu in cells, and cytotoxicity. Contrary to what is reported in most studies, we conclude that interaction with cell components and cell death involves the separate action of Cu ions and phen molecules, not [Cu(phen)(n)] species. This conclusion should similarly apply to many other Cu-ligand systems reported to date.