Showing: 10 from total: 2413 publications
81. Nanoporous anodic alumina layers obtained from novel deep eutectic solvent formulations
Fernandes, PMV ; Brincoveanu, O ; Pantazi, A ; Petica, A ; Pereira, CM ; Silva, AF ; Enachescu, M ; Anicai, L
in TRANSACTIONS OF THE INSTITUTE OF METAL FINISHING, 2023, ISSN: 0020-2967,  Volume: 101, 
Article,  Indexed in: crossref, scopus, unpaywall, wos 
Abstract The possible fabrication of porous anodic oxide films on aluminium in ionic liquids based on choline dihydrogen citrate eutectic mixtures both with oxalic acid and isopropyl alcohol and ethylene glycol, has been investigated. The anodisation has been carried out in either potentiostatic or galvanostatic regime, at temperatures of 45-80 degrees C, for different process durations. Quite compact, uniform anodic alumina layers have been obtained. Based on AFM and SEM investigations, pore diameters between 50 and 80 nm and interpore distances in the range of 160-200 nm have been estimated, with values influenced by the electrolyte type and anodisation conditions. The highest anodisation rate of about 0.4 mu m min(-1) has been determined by applying operation temperatures of 60 degrees C. The recorded EIS spectra showed a pure capacitive behaviour and high anodic oxide resistances of 10(6)-10(7) omega cm(2) order.

82. Polyfluoroalkyl Substances (PFASs) Detection Via Carbon Dots: A Review
Sendao, RMS ; da Silva, JCGE ; da Silva, LP
in SUSTAINABLE CHEMISTRY, 2023, ISSN: 2673-4079,  Volume: 4, 
Review,  Indexed in: authenticus, crossref, unpaywall, wos 
P-00Z-K66
Abstract PFASs are a class of highly persistent chemicals that are slowly infiltrating soils and waterways. Thus, there is a great need for fast, sensitive, and reliable techniques to detect PFASs. Conventional methods, such as LC-MS/SPE, allow high sensitivities. However, such methods can be complex and expensive. Considering this, it is not surprising that the scientific community has turned their attention to the search for alternatives. New types of PFAS sensors have been reported over the years, being generally part of three classes: optical, electrochemical, or hybrid sensors. Carbon dots (CDs) are new alternative fluorescent sensors that can present great affinity towards PFASs, while allowing for a fast response and promising sensitivity and selectivity. Furthermore, CDs have more attractive properties than traditional fluorophores and even metal-based nanomaterials that make them better candidates for sensing applications. Thus, CDs display great potential for permitting a fast and accurate quantification of PFASs. This review aims to serve as a basis for the future development and optimization of CD-based fluorescent sensors for PFASs.

83. Sustainable Sawdust/Eucalyptol Absorption Matrix for Odor Slow-Release in Plywood Floor
Logvina, Y ; Fernandes, S ; da Silva, LP ; da Silva, JE
in SUSTAINABLE CHEMISTRY, 2023, ISSN: 2673-4079,  Volume: 4, 
Article,  Indexed in: crossref, unpaywall, wos 
Abstract A sustainable matrix based on eucalyptol essential oil/sawdust was developed and applied on laminated plywood. This finish aims to serve as a eucalyptol odor slow release. Eucalyptol odor release was monitored with gas chromatography coupled with a flame ionization detector (GC-FID: Limits of Detection and Quantification of 0.70 g/m3 and 2.11 g/m3, respectively, and with linearity up to 18.6 g/m3). Measurement of the eucalyptol odor released was performed during a six-month period, and it was found that the release followed a first-order exponential decay with a decay rate constant of 0.0169 per day. The half-life was determined to be of 48 days. The granulometry and particle size porosity of sawdust were analyzed by Scanning Electron Microscopy. A sawdust size fraction of 112-200 mu m showed the best eucalyptol absorption capacity, with 1:3 masses ratio (sawdust:eucalyptol). The release duration of eucalyptol is influenced by the quantity of the eucalyptol-sawdust composite and the aperture size for release. Through the determination of this relationship, it was found that applying 15.0 g of the composite through a 0.8 mm diameter aperture resulted in a 6-month eucalyptol release period. This outcome is regarded as highly favorable, considering the inherent high volatility of eucalyptol and the relatively small amount of composite required for future product applications. The new product is characterized by a carbon footprint (considering the industry frontiers) of 5.94 kg CO2eq/m2 of plywood floor.

84. Synchrotron-based FTIR evaluation of biochemical changes in cancer and noncancer cells induced by brominated marine coelenteramine
Magalhaes, CM ; Ducic, T ; Pereira, RB ; Gonzalez-Berdullas, P ; Rodriguez-Borges, JE ; Pereira, DM ; da Silva, JCGE ; Algarra, M ; da Silva, LP
in ARCHIVES OF BIOCHEMISTRY AND BIOPHYSICS, 2023, ISSN: 0003-9861,  Volume: 743, 
Article,  Indexed in: crossref, scopus, unpaywall, wos 
Abstract The mode of action toward gastric cancer cells of brominated Coelenteramine, an analogue of a metabolic product of a marine bioluminescent reaction, was investigated by synchrotron radiation-based Fourier Transform Infrared spectrocopy (FTIR). This method revealed that the anticancer activity of brominated Coelenteramine is closely connected with cellular lipids, by affecting their organization and composition. More specifically, there is an increasing extent of oxidative stress, which results in changes in membrane polarity, lipid chain packing and lipid composition. However, this effect was not observed in a noncancer cell line, helping to explain its selectivity profile. Thus, synchrotron radiation-based FTIR helped to identify the potential of this Coelenteramine analogue in targeting membrane lipids, while proving to be a powerful technique to probe the mechanism of anticancer drugs.

85. Drivers of FDI in small states
Forte, R ; Neves, C
in JOURNAL OF THE ASIA PACIFIC ECONOMY, 2023, ISSN: 1354-7860,  Volume: 28, 
Article,  Indexed in: crossref, scopus, wos 
Abstract This paper examines the determinants of FDI in small states, as only a small number of studies have analyzed the determinants of FDI in these countries. Small states have particular features that justify the need for a deeper analysis. Based on a panel data for 42 small states between 2005 and 2019, results clearly indicate the importance of the quality of human capital and the availability of infrastructures as the strongest drivers of FDI in small states. The country's level of openness, the availability of natural resources, the level of corporate tax and control of corruption also seems to play a relevant role therein. Moreover, the results suggest that the determinants differ depending on the region to which the country belongs and differ between island and non-island countries. These results can help small countries in defining policies that help them to attract FDI, which is crucial for their sustainable development.

86. Assessment of Surface Water Quality Using the Water Quality Index (IWQ), Multivariate Statistical Analysis (MSA) and Geographic Information System (GIS) in Oued Laou Mediterranean Watershed, Morocco
Azhari, HE ; Cherif, E ; Sarti, O ; Azzirgue, E ; Dakak, H ; Yachou, H ; da Silva, JCGE ; Salmoun, F
in WATER, 2023, ISSN: 2073-4441,  Volume: 15, 
Article,  Indexed in: crossref, scopus, wos 
Abstract Surface water is used for a variety of purposes, including agriculture, drinking water, and other services. Therefore, its quality is crucial for irrigation, human welfare, and health. Thus, the main objective is to improve surface water quality assessment and geochemical analysis to evaluate anthropogenic activities' impact on surface water quality in the Oued Laou watershed, Northern Morocco. Thirteen surface water samples were characterized for 26 physicochemical and biological parameters. In this aspect, emerging techniques such as multivariate statistical approaches (MSA), water quality indices (WQI), irrigation water quality (IWQI), and Geographic Information System (GIS) were employed to identify the sources of surface water pollution, their suitability for consumption, and the distribution of surface water quality. The results showed that the major ion concentrations were reported in the following order: Ca2+, Na+, Mg2+, and K+; and HCO3- > CO32- > Cl- > SO42- > NO3- > F- > PO43- > NO2-. It was also demonstrated that almost all parameters had concentrations lower than World Health Organization (WHO) limits, except for bicarbonate ions (HCO3-) and the biochemical oxygen demand for five days (BOD5), which exceeded the WHO limits at 120 mg/L and 3 mg/L, respectively. Furthermore, the types of Ca2+-HCO3- (Calcium-Bicarbonate) and Ca2+-Mg2+-HCO3- (Calcium-Magnesium-Bicarbonate) predominated in surface water. The Principal Component Analysis (PCA) indicates that the Oued Laou river was exposed to two forms of contamination, the first being attributed to anthropogenic activities such as agriculture, while the second reflects the water-sediment interaction. The Hierarchical Cluster Analysis (HCA), reflecting the mineralization in the study area, has classified the samples into four clusters. The Inverse Distance Weighting (IDW) of the WQI indicates that 7.69% and 38.46% of the surface water represent, respectively, excellent and good quality for drinking. At the same time, the IWQI revealed that 92.30% of the water surface is good for irrigation. As a result, the combination of WQIs, PCA, IWQI, and GIS techniques is effective in providing clear information for assessing the suitability of surface water for drinking and its controlling factors and can also support decision-making in susceptible locations such as the Oued Laou river in northern Morocco.

87. Phytochemical Compounds and Anticancer Activity of Cladanthus mixtus Extracts from Northern Morocco
El Mihyaoui, A ; Charfi, S ; Erbiai, E ; Pereira, M ; Duarte, D ; Vale, N ; Castillo, MEC ; Badoc, A ; Lamarti, A ; da Silva, JCGE ; Arnao, MB
in CANCERS, 2023, ISSN: 2072-6694,  Volume: 15, 
Article,  Indexed in: crossref, scopus, wos 
Abstract Simple Summary Cancer is a dramatic illness that ranks among the most pressing health concerns facing humanity and necessitates a proactive approach to treatment. Phytochemicals are regarded as interesting molecules for the development of anticancer drugs due to their pleiotropic effects on broad targets. The actions of phytochemicals are focused on tumor cells alone, with no negative effects on normal cells. The intricate process of carcinogenesis involves numerous signaling cascades. This study examined the effects of four organ extracts from a Mediterranean endemic plant, Cladanthus mixtus, on human tumor cells. To the best of our knowledge, this is the first study on this plant from northern Morocco showing relevant antiproliferative activity against two cancer cell lines and one non-tumoral cell line. Many of the chemotherapeutic drugs for the treatment of cancer are molecules identified and isolated from plants or their synthetic derivatives. This work aimed to identify the bioactive compounds using LC-MS and GC-MS and to evaluate the anticancer activity of the methanolic extracts of roots, stems, leaves, and flowers from Cladanthus mixtus. The anticancer activity was evaluated in vitro against two cancer cell lines: human breast carcinoma (MCF-7) and human prostate carcinoma (PC-3), using the MTT assay and microscopic observation. A human normal lung fibroblast (MRC-5) was included to determine the extract's safety for non-tumoral cells. The chemical composition results by LC-MS analysis revealed the presence of 24 phenolic compounds. Furthermore, GC-MS analysis allowed the identification of many biomolecules belonging to terpenoids, esters, alcohols, alkanes, fatty acids, organic acids, benzenes, phenols, ketones, carbonyls, amines, sterols, and other groups. The findings suggest that the majority of C. mixtus extracts have antiproliferative activity against two cancer cell lines, MCF-7 and PC-3, and one non-tumoral cell line, MRC-5. The activity was dose-dependent, and the highest effect was obtained with leaf extract in the two cancer cell lines. Moreover, these extracts demonstrated an acceptable toxicological profile against normal cells. Overall, C. mixtus extracts revealed promising antitumor properties provided by their phytochemical composition.

88. The mitochondria-targeted antioxidant AntiOxCIN4 protects against cardiac oxidative/nitrosative stress in the amyotrophic lateral sclerosis SOD1G93A mouse
Mena, D ; Cagide, F ; Benfeito, S ; Soares, P ; Grilo, L ; Pinheiro, P ; Teixeira, J ; Borges, F ; Oliveira, PJ ; Duarte, AI
in EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, 2023, ISSN: 0014-2972,  Volume: 53, 
Abstract,  Indexed in: wos 

89. The mitochondria-targeted antioxidant AntiOxCIN4 attenuates brain and skeletal muscle oxidative/nitrosative stress in the amyotrophic lateral sclerosis SOD1G93A mouse
Mena, D ; Soares, P ; Cagide, F ; Benfeito, S ; Grilo, L ; Silva, DF ; Pinheiro, P ; Ferreiro, E ; Teixeira, J ; Silva, F ; Borges, F ; Oliveira, PJ ; Duarte, AI
in EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, 2023, ISSN: 0014-2972,  Volume: 53, 
Abstract,  Indexed in: wos 

90. Annealing-assisted optimization for persistency of afterglow of SrAl2O4:Eu2+/Dy3+ microparticles for forensic detection
Kumar, A ; Crista, DMA ; Núñez-Montenegro, A ; da Silva, JCGE ; Verma, SK
in RSC ADVANCES, 2023, ISSN: 2046-2069,  Volume: 13, 
Article,  Indexed in: crossref, scopus, wos 
Abstract In the present work, Eu2+/Dy3+ ions doped/co-doped into persistent SrAl2O4 microparticles have been developed through solid-state synthesis followed by homogenization and particle size reduction in a ball milling device. These particles have shown a broad and long-persistent afterglow around the 528 nm wavelength of electromagnetic radiation through a broad excitation at around 400 nm. The luminescence intensity was optimized through the selection of different annealing temperatures in the range of 1100 C-degrees to 1500 C-degrees, with intervals of 100 C-degrees. Several structural and optical characterization techniques, such as XRD, SEM, FTIR, thermogravimetric analysis, and photoluminescence, were utilized to judge the preparation and ability of these particles in possible applications in latent fingermark detection on various difficult surfaces. The persistency and stability of these particles were calculated using a digital lux meter.