Publications by authors named "Paulo Abreu"

A new series of Zn(II) and Cu(II)-based porphyrin complexes 5a and 5b doubly functionalised with carbazole units were developed to be used as hole-transporting materials (HTMs) in perovskite solar cells (PSCs). These complexes were obtained a nucleophilic substitution reaction mediated by PhI(OAc)/NaAuCl·2HO, or using C-N transition metal-assisted coupling. The hole extraction capability of 5a and 5b was assessed using cyclic voltammetry; this study confirmed the better alignment of the Zn(II) complex 5a with the perovskite valence band level, compared to the Cu(II) complex 5b.

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Toxic heavy metals are priority pollutants in wastewater, commonly present in dangerous concentrations in many places across the globe. Although in trace quantities copper is a heavy metal essential to human life, in excess it causes various diseases, whereby its removal from wastewater is a necessity. Among several reported materials, chitosan is a highly abundant, non-toxic, low-cost, biodegradable polymer, comprising free hydroxyl and amino groups, that has been directly applied as an adsorbent or chemically modified to increase its performance.

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Natural products from the marine environment as well as microalgae, have been known for the complexity of the metabolites they produce due to their adaptability to different environmental conditions, which has been an inexhaustible source of several bioactive properties, such as antioxidant, anti-tumor, and antimicrobial. This study aims to characterize the main metabolites of three species of microalgae (, and ), which have important applications in the biofuel and nutrition industries, by H High-resolution magic angle spinning nuclear magnetic resonance (H HR-MAS NMR), a method which is non-destructive, is highly reproducible, and requires minimal sample preparation. Even though the three species were found in the same ecosystem and a superior production of lipid compounds was observed, important differences were identified in relation to the production of specialized metabolites.

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Details on the unexpected formation of two new (dimethylamino)methyl corrole isomers from the reaction of 5,10,15-tris(pentafluorophenyl)corrolatogallium(III) with sarcosine and paraformaldehyde are presented. Semi-empirical calculations on possible mechanism pathways seem to indicate that the new compounds are probably formed through a Mannich-type reaction. The extension of the protocol to the free-base 5,10,15-tris(pentafluorophenyl)corrole afforded an unexpected new seven-membered ring corrole derivative, confirming the peculiar behavior of corroles towards known reactions when compared to the well-behaved porphyrin counterparts.

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Foreign direct investment (FDI) is an important driver of the increasing globalization of the word economy, and despite being a widely studied phenomenon, studies on the effects of FDI on host countries' social welfare are scarce. So, this work aims to analyze the impact of FDI on welfare measured through the human development index and its three dimensions (education, life expectancy, and income). Based on a sample of 146 countries for the period 2002-2019, the results obtained by two-staged least squares-instrumental variable estimation suggest that FDI impact on social welfare depends on the countries' human capital which reflects countries' absorptive capacity.

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The SARS-CoV-2 pandemic emphasized effective cleaning and disinfection of common spaces as an essential tool to mitigate viral transmission. To address this problem, decontamination technologies based on UV-C light are being used. Our aim was to generate coherent and translational datasets of effective UV-C-based SARS-CoV-2 inactivation protocols for the application on surfaces with different compositions.

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Microalgae, due to its rapid growth, low nutritional requirements, and versatility of adaptation to different environmental conditions, has aroused the biotechnological interest, synthesizing novel molecules with antioxidant, anticoagulant, anti-inflammatory, antitumor, and antimicrobial activities. In this sense, we carried out the bioprospection of Chaetoceros muelleri, a marine diatom employed in aquaculture, as a candidate to the development of new drugs for the treatment of bacterial infections. The chemical profile of extracts in different solvents (hexane, chloroform, methylene chloride, ethyl acetate, methanol, and acetone) were analyzed by H-NMR.

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The vast capacity for maintenance and dissemination in the environment are major challenges for the control of Salmonella spp. in poultry farms. The aim of this study was to assess environmental contamination by non-typhoidal Salmonella in successive broiler flocks in nine commercial broiler farms integrated with three companies in the south of Brazil, for a twelve-month production period.

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Infrared thermal imaging (IRT) has been a target of research for biomedical musculoskeletal applications, due to the possible association of the physiological data that it provides, through skin temperature measurement, with pathological states. The aim of this systematic review is to acquaint the outcomes of the biomedical application of IRT in arm and forearm evaluation and its future perspectives of research. During the literature review, 926 articles were identified using the search engines PubMed and Scopus, and 10 articles were retrieved from other sources.

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Background: This work presents a comparison and selection of different machine learning classification techniques applied in the identification of objects using data collected by an instrumented glove during a grasp process. The selected classifiers techniques can be applied to e-rehabilitation and e-training exercises for different pathologies, as in aphasic patients.

Methods: The adopted method uses the data from a commercial instrumented glove.

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This study investigates the capacity of phenolic extracts from microalgae sp. and sp. to inhibit enzymes and free radical activities, intending to find an innovative way to slow down food damage.

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Electron transfer reactions are arguably the simplest chemical reactions but they have not yet ceased to intrigue chemists. Charge-separation and charge-recombination reactions are at the core of life-sustaining processes, molecular electronics and solar cells. Intramolecular electron donor-acceptor systems capture the essential features of these reactions and enable their fundamental understanding.

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This paper describes a system for training healthcare practitioners in the identification of different arterial pulses. The driving system uses a linear solenoid in an open loop force control. Due to the large hysteresis it exhibited, a form of compensation was implemented, based on the classic Preisach model of hysteresis.

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Four soybean meal-based diets containing increasing levels of an enzyme complex (E50, E100, E150 and E200 at 50, 100, 150 and 200 g ton-1, respectively) and one soybean meal-based diet without the enzyme complex (E0) were fed in triplicate to M. liza juveniles in a semi-static flow system with 20 fish per tank for 75 days. There were no differences between the treatments for animal performance parameters, but fish fed the enzyme complex treatment exhibited significantly (P<0.

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Unlabelled: The effects of two alternative sources of animal fat-derived biodiesel feedstock on CO, CO, NO tailpipe emissions as well as fuel consumption were investigated. Biodiesel blends were produced from chicken and swine fat waste (FW-1) or floating fat (FW-2) collected from slaughterhouse wastewater treatment processes. Tests were conducted in an unmodified stationary diesel engine operating under idling conditions in attempt to simulate slow traffic in urban areas.

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Multinuclear ((1)H, (13)C, (95)Mo and (183)W) NMR spectroscopy, combined with DFT calculations, provides detailed information on the complexation between the Mo(VI) and W(VI) oxoions and 8-hydroxyquinoline-5-sulfonate (8-HQS) in aqueous solution. Over the concentration region studied, Mo(VI) and W(VI) oxoions form three homologous complexes with 8-HQS in water in the pH range 2-8. Two of these, detected at pH < 6, are mononuclear 1 : 2 (metal : ligand) isomers, with the metal centre (MO2(2+)) coordinated to two 8-HQS ligands.

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Time series of environmental measurements are essential for detecting, measuring and understanding changes in the Earth system and its biological communities. Observational series have accumulated over the past 2-5 decades from measurements across the world's estuaries, bays, lagoons, inland seas and shelf waters influenced by runoff. We synthesize information contained in these time series to develop a global view of changes occurring in marine systems influenced by connectivity to land.

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Microalgae is largely used in aquaculture as feed. More recently, these microorganisms have been considered as an important feedstock for biodiesel production. However, the concentration of produced biomass represents a large parcel of production costs.

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The Patos Lagoon estuary is a microtidal system that is strongly regulated by atmospheric forces, including remote large-scale phenomena such as the El Niño Southern Oscillation (ENSO), which affects precipitation patterns in the region. In this study, we investigated whether the bacterial community composition (BCC), community-level physiological profiles (CLPP), and a set of environmental variables were affected by the transition from a moderate El Niño to a strong La Niña event (June 2010 to May 2011). We identified two distinct periods: a period following El Niño that was characterized by low salinity and high concentrations of NO3(-) and PO4(-3) and low molecular weight (LMW) substances and a period following La Niña during which salinity, temperature, and transparency increased and the concentrations of nutrients and LMW substances decreased.

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We employed a Lagrangian-like sampling design to evaluate bacterial community composition (BCC--using temporal temperature gel gradient electrophoresis), community-level physiological profiles (CLPP--using the EcoPlate™ assay), and influencing factors in different salinity waters in the highly dynamic Patos Lagoon estuary (southern Brazil) and adjacent coastal zone. Samples were collected monthly by following limnetic-oligohaline (0-1), mesohaline (14-16), and polyhaline (28-31) waters for 1 year. The BCC was specific for each salinity range, whereas the CLPPs were similar for mesohaline and polyhaline waters, and both were different from the limnetic-oligohaline samples.

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White spot syndrome virus (WSSV) and Infectious hypodermal and hematopoietic necrosis virus (IHHNV) are two infectious agents associated to economic losses in shrimp aquaculture. As virus spread occurs through vectors and hosts, this study sought to verify the presence of WSSV and IHHNV in Neohelice granulata crab from Lagoa dos Patos estuary in Brazil and nearby shrimp farms. DNA extractions were performed with phenol/chloroform protocol.

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Multinuclear ((1)H, (13)C and (27)Al) magnetic resonance spectroscopy (1D and 2D), DFT calculations and fluorescence have been used to study the complexation of 8-hydroxyquinoline-5-sulfonate (8-HQS) with Al(III). The study combines the high sensitivity of luminescence techniques, the selectivity of multinuclear NMR spectroscopy with the structural details accessible through DFT calculations, and aims to provide a detailed understanding of the complexation between the Al(3+) ion and 8-HQS. A full speciation study has been performed and over the concentration region studied, the Al(3+) ion forms complexes with 8-HQS in an aqueous solution in the pH range 2-6.

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Clinical behavior analysis often targets the shaping of clients' functional interpretations of/or rules about his own behavior. These are referred to as clinically relevant behavior 3 (CRB3) in functional analytic psychotherapy (FAP). We suggest that CRB3s should be seen as contingency-specifying stimuli (CSS), due to the their ability to change the function of stimuli-including descriptions of variables involved in the client's behavioral problems as well as descriptions of variables associated with improvement or therapeutic change.

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