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1.
Langmuir ; 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39153215

RESUMO

1-Dodecyl-2-methylpyridinium bromide ([C12-2-Pic][Br]) and 1-hexadecyl-2-methylpyridinium bromide ([C16-2-Pic][Br]) are two ionic liquid crystals presenting thermotropic smectic phases above 80 °C. Aiming to take advantage of the liquid crystalline properties at lower temperatures, lyotropic aqueous systems were prepared from these two organic salts. Both systems were characterized by polarized optical microscopy (POM), X-ray powder diffraction (XRD), and fast field cycling nuclear magnetic resonance (FFC-NMR) relaxometry to assess their texture, phase structure, and molecular dynamics, respectively. The mesomorphic behavior was induced at room temperature. Moreover, the lyotropic [C12-2-Pic][Br]aq revealed a smectic phase with higher separation between layers, different from the lamellar phases found in the thermotropic system (S1 and SA), which is thermally stable up to 50 °C. Furthermore, the surfactant nature of the ionic liquids diluted solutions investigated in this work allowed the formation of foams. It was found that the precursor solutions of the lyotropic dilutions with the longest alkyl chain ([C16-2-Pic][Br]aq) originated liquid foams with more stable structures than those of [C12-2-Pic][Br]aq.

2.
Inorg Chem ; 63(29): 13321-13337, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38987901

RESUMO

Two new porous three-dimensional cadmium(II) metal-organic frameworks (MOFs) containing thiophene-appended carboxylate acid ligands, formulated as [Cd(L1)(4,4'-Bipy)]n.2n(DMF) (1) and [Cd(L2)(4,4'-Bipy)]n.2n(DMF) (2) [where L1 = 5-{(thiophen-2-ylmethyl)amino}isophthalate, L2 = 5-{(thiophen-3-ylmethyl)amino}isophthalate, 4,4'-Bipy = 4,4'-bipyridine, and DMF = N,N'-dimethylformamide] have been synthesized and structurally characterized. The gas adsorption analysis of the activated MOFs shows that they specifically capture CO2 (uptake amount 4.36 mmol/g under 1 bar at 195 K) over N2 and CH4. Moreover, both MOFs show a gate-opening-closing phenomenon, which features the S-shaped isotherms with impressive hysteretic desorption during the CO2 adsorption-desorption process at 195 K. Ideal adsorbed solution theory (IAST) calculations of these MOFs displayed that the obtained selectivity values for CO2/CH4 (50:50) and CO2/N2 (15:85) are approximately 8.6-23 and 93-565, respectively. Configurational bias Monte Carlo simulation was performed to understand the mechanism behind the better CO2 adsorption by these MOFs. Catalytic activity of the MOFs for the CO2 fixation reactions with different epoxides to form cyclic carbonates were tested. These MOFs demonstrated a significantly high conversion (94-99%) of epichlorohydrin to the corresponding cyclic carbonate within 8 h of reaction time at 1 bar of CO2 pressure, at 70 °C, and they can be reused up to five cycles without losing considerably their activity.

3.
Appl Microbiol Biotechnol ; 108(1): 329, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38727750

RESUMO

Xylanases are key biocatalysts in the degradation of the ß-1,4-glycosidic linkages in the xylan backbone of hemicellulose. These enzymes are potentially applied in a wide range of bioprocessing industries under harsh conditions. Metagenomics has emerged as powerful tools for the bioprospection and discovery of interesting bioactive molecules from extreme ecosystems with unique features, such as high temperatures. In this study, an innovative combination of function-driven screening of a compost metagenomic library and automatic extraction of halo areas with in-house MATLAB functions resulted in the identification of a promising clone with xylanase activity (LP4). The LP4 clone proved to be an effective xylanase producer under submerged fermentation conditions. Sequence and phylogenetic analyses revealed that the xylanase, Xyl4, corresponded to an endo-1,4-ß-xylanase belonging to glycosyl hydrolase family 10 (GH10). When xyl4 was expressed in Escherichia coli BL21(DE3), the enzyme activity increased about 2-fold compared to the LP4 clone. To get insight on the interaction of the enzyme with the substrate and establish possible strategies to improve its activity, the structure of Xyl4 was predicted, refined, and docked with xylohexaose. Our data unveiled, for the first time, the relevance of the amino acids Glu133 and Glu238 for catalysis, and a close inspection of the catalytic site suggested that the replacement of Phe316 by a bulkier Trp may improve Xyl4 activity. Our current findings contribute to enhancing the catalytic performance of Xyl4 towards industrial applications. KEY POINTS: • A GH10 endo-1,4-ß-xylanase (Xyl4) was isolated from a compost metagenomic library • MATLAB's in-house functions were developed to identify the xylanase-producing clones • Computational analysis showed that Glu133 and Glu238 are crucial residues for catalysis.


Assuntos
Compostagem , Endo-1,4-beta-Xilanases , Escherichia coli , Metagenômica , Filogenia , Endo-1,4-beta-Xilanases/genética , Endo-1,4-beta-Xilanases/metabolismo , Endo-1,4-beta-Xilanases/química , Endo-1,4-beta-Xilanases/isolamento & purificação , Escherichia coli/genética , Escherichia coli/metabolismo , Metagenoma , Biblioteca Gênica , Microbiologia do Solo , Xilanos/metabolismo , Clonagem Molecular , Fermentação , Expressão Gênica , Simulação de Acoplamento Molecular
4.
J Environ Manage ; 351: 119875, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38157581

RESUMO

Phosphorus (P) removal from urban wastewater is increasingly relevant in the wastewater treatment sector. The present work aims to contribute to the study of the adsorption process as a P removal technology. Biogenic calcium carbonate from industrial eggshell waste prepared by milling and calcination was used as an adsorbent. Batch adsorption experiments were conducted using real wastewater with 40 mg P/L (orthophosphate), original pH 7.33, under stirring conditions (100 rpm). The adsorbent was characterized using SEM-EDS, XRD, and FTIR-ATR before and after adsorption. From an initial screening of calcination times (15, 30, 60, and 120 min) and considering a balance between P removal and energy saving, the adsorbent selected was eggshell calcined at 700 °C for 60 min. The Langmuir isotherms describe the experimental data with a maximum adsorption capacity of 4.57 mg P/g at 25 °C. The adsorption process reached equilibrium within 120 min for different dosages (5, 10, and 20 g/L at 25 °C). Batch experiments showed that SO42-, at a concentration of 2689 mg/L reduced the P adsorption selectivity for dosages ≤10 g/L at 25 °C. Characterization of the loaded adsorbent shows that P adsorption from real wastewater is mostly electrostatic attraction, with the contribution of ligand exchange and microprecipitation. The adsorption capacity and behavior of the selected adsorbent seem promising for P removal from urban wastewater compared with other low-cost adsorbents.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Fósforo/química , Adsorção , Carbonato de Cálcio/química , Cinética , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio , Resíduos Industriais
5.
J Pediatr ; 252: 56-60.e2, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36067875

RESUMO

OBJECTIVE: To report the effectiveness of early molecular diagnosis in the clinical management of rare diseases, presenting 8 patients with 8p23.1DS who have clinical features that overlap the phenotypic spectrum of 22q11.2DS. STUDY DESIGN: This report is part of a previous study that aims to provide a precocious molecular diagnosis of the 22q11.2 deletion syndrome in 118 infants with congenital heart disease. To confirm the clinical diagnosis, patients underwent comparative genomic screening by the multiplex ligation-dependent probe amplification (MLPA) assay with the SALSA MLPA probemix kits P064-B2, P036-E1, P070-B2, P356-A1, and P250- B1. Subsequently, the patients performed the genomic microarray using the Infinium CytoSNP-850K BeadChip to confirm the deletion, determine the breakpoints of the deletion, and search for genomic copy number variations. RESULTS: MLPA performed with 3 different kits revealed the 8p23.1 typical deletion involving the PPP1R3B, MSRA, and GATA4 genes in the 5 patients. The array analysis was performed on these 5 patients and 3 other patients (8 patients) who also had clinical suspicion of 22q11 deletion (8 patients) allowed a precise definition of the breakpoints and excluded other genomic abnormalities. CONCLUSIONS: Cytogenomic screening was efficient in establishing a differential diagnosis and ruling out the presence of other concomitant syndromes. The clinical picture of the 8p23.1 deletion syndrome is challenging; however, cytogenomic tools can provide an exact diagnosis and help to clarify the genotype-phenotype complexity of these patients. Our reports underline the importance of early diagnosis and clinical follow-up of microdeletion syndromes.


Assuntos
Síndrome de DiGeorge , Cardiopatias Congênitas , Humanos , Deleção Cromossômica , Variações do Número de Cópias de DNA , Síndrome de DiGeorge/diagnóstico , Fenótipo , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/genética
6.
Appl Microbiol Biotechnol ; 107(17): 5379-5401, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37417976

RESUMO

The renewable, abundant , and low-cost nature of lignocellulosic biomass can play an important role in the sustainable production of bioenergy and several added-value bioproducts, thus providing alternative solutions to counteract the global energetic and industrial demands. The efficient conversion of lignocellulosic biomass greatly relies on the catalytic activity of carbohydrate-active enzymes (CAZymes). Finding novel and robust biocatalysts, capable of being active under harsh industrial conditions, is thus imperative to achieve an economically feasible process. In this study, thermophilic compost samples from three Portuguese companies were collected, and their metagenomic DNA was extracted and sequenced through shotgun sequencing. A novel multi-step bioinformatic pipeline was developed to find CAZymes and characterize the taxonomic and functional profiles of the microbial communities, using both reads and metagenome-assembled genomes (MAGs) as input. The samples' microbiome was dominated by bacteria, where the classes Gammaproteobacteria, Alphaproteobacteria, and Balneolia stood out for their higher abundance, indicating that the degradation of compost biomass is mainly driven by bacterial enzymatic activity. Furthermore, the functional studies revealed that our samples are a rich reservoir of glycoside hydrolases (GH), particularly of GH5 and GH9 cellulases, and GH3 oligosaccharide-degrading enzymes. We further constructed metagenomic fosmid libraries with the compost DNA and demonstrated that a great number of clones exhibited ß-glucosidase activity. The comparison of our samples with others from the literature showed that, independently of the composition and process conditions, composting is an excellent source of lignocellulose-degrading enzymes. To the best of our knowledge, this is the first comparative study on the CAZyme abundance and taxonomic/functional profiles of Portuguese compost samples. KEY POINTS: • Sequence- and function-based metagenomics were used to find CAZymes in compost samples. • Thermophilic composts proved to be rich in bacterial GH3, GH5, and GH9 enzymes. • Compost-derived fosmid libraries are enriched in clones with ß-glucosidase activity.


Assuntos
Celulases , Compostagem , Microbiota , Metagenômica , Lignina/metabolismo , Carboidratos , Bactérias/metabolismo , Celulases/metabolismo
7.
Int J Mol Sci ; 24(10)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37240166

RESUMO

Thyroid diseases affect a considerable portion of the population, with hypothyroidism being one of the most commonly reported thyroid diseases. Levothyroxine (T4) is clinically used to treat hypothyroidism and suppress thyroid stimulating hormone secretion in other thyroid diseases. In this work, an attempt to improve T4 solubility is made through the synthesis of ionic liquids (ILs) based on this drug. In this context, [Na][T4] was combined with choline [Ch]+ and 1-(2-hydroxyethyl)-3-methylimidazolium [C2OHMiM] + cations in order to prepare the desired T4-ILs. All compounds were characterized by NMR, ATR-FTIR, elemental analysis, and DSC, aiming to check their chemical structure, purities, and thermal properties. The serum, water, and PBS solubilities of the T4-ILs were compared to [Na][T4], as well as the permeability assays. It is important to note an improved adsorption capacity, in which no significant cytotoxicity was observed against L929 cells. [C2OHMiM][T4] seems to be a good alternative to the commercial levothyroxine sodium salt with promising bioavailability.


Assuntos
Líquidos Iônicos , Tiroxina , Tiroxina/síntese química , Tiroxina/farmacocinética , Tiroxina/toxicidade , Disponibilidade Biológica , Solubilidade , Líquidos Iônicos/síntese química , Líquidos Iônicos/farmacocinética , Líquidos Iônicos/toxicidade , Células L , Animais , Camundongos , Permeabilidade
8.
Int J Behav Nutr Phys Act ; 19(1): 107, 2022 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-36028860

RESUMO

BACKGROUND: Physical activity mass media campaigns can deliver physical activity messages to many people, but it remains unclear whether they offer good value for money. We aimed to investigate the cost-effectiveness, cost-utility, and costs of physical activity mass media campaigns. METHODS: A search for economic evaluations (trial- or model-based) and costing studies of physical activity mass media campaigns was performed in six electronic databases (June/2021). The authors reviewed studies independently. A GRADE style rating was used to assess the overall certainty of each modelled economic evaluation. Results were summarised via narrative synthesis. RESULTS: Twenty-five studies (five model-based economic evaluations and 20 costing studies) were included, and all were conducted in high-income countries except for one costing study that was conducted in a middle-income country. The methods and assumptions used in the model-based analyses were highly heterogeneous and the results varied, ranging from the intervention being more effective and less costly (dominant) in two models to an incremental cost of US$130,740 (2020 base year) per QALY gained. The level of certainty of the models ranged from very low (n = 2) to low (n = 3). Overall, intervention costs were poorly reported. CONCLUSIONS: There are few economic evaluations of physical activity mass media campaigns available. The level of certainty of the models was judged to be very low to low, indicating that we have very little to little confidence that the results are reliable for decision making. Therefore, it remains unclear to what extent physical activity mass media campaigns offer good value for money. Future economic evaluations should consider selecting appropriate and comprehensive measures of campaign effectiveness, clearly report the assumptions of the models and fully explore the impact of assumptions in the results. REVIEW REGISTRATION: https://bit.ly/3tKSBZ3.


Assuntos
Exercício Físico , Meios de Comunicação de Massa , Análise Custo-Benefício , Humanos
9.
Br J Sports Med ; 56(23): 1353-1365, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36302631

RESUMO

OBJECTIVE: To investigate cost-effectiveness and costs of fall prevention exercise programmes for older adults. DESIGN: Systematic review. DATA SOURCES: Medline, Embase, Web of Science, Scopus, National Institute for Health Research Economic Evaluation Database, Health Technology Assessment database, Tufts Cost-Effectiveness Analysis Registry, Research Papers in Economics and EconLit (inception to May 2022). ELIGIBILITY CRITERIA FOR STUDY SELECTION: Economic evaluations (trial-based or model-based) and costing studies investigating fall prevention exercise programmes versus no intervention or usual care for older adults living in the community or care facilities, and reporting incremental cost-effectiveness ratio (ICER) for fall-related outcomes or quality-adjusted life years (QALY, expressed as cost/QALY) and/or intervention costs. RESULTS: 31 studies were included. For community-dwelling older adults (21 economic evaluations, 6 costing studies), results ranged from more effective and less costly (dominant) interventions up to an ICER of US$279 802/QALY gained and US$11 986/fall prevented (US$ in 2020). Assuming an arbitrary willingness-to-pay threshold (US$100 000/QALY), most results (17/24) were considered cost-effective (moderate certainty). The greatest value for money (lower ICER/QALY gained and fall prevented) appeared to accrue for older adults and those with high fall risk, but unsupervised exercise appeared to offer poor value for money (higher ICER/QALY). For care facilities (two economic evaluations, two costing studies), ICERs ranged from dominant (low certainty) to US$35/fall prevented (moderate certainty). Overall, intervention costs varied and were poorly reported. CONCLUSIONS: Most economic evaluations investigated fall prevention exercise programmes for older adults living in the community. There is moderate certainty evidence that fall prevention exercise programmes are likely to be cost-effective. The evidence for older adults living in care facilities is more limited but promising. PROSPERO REGISTRATION NUMBER: PROSPERO 2020 CRD42020178023.


Assuntos
Terapia por Exercício , Exercício Físico , Humanos , Idoso , Análise Custo-Benefício , Anos de Vida Ajustados por Qualidade de Vida , Terapia por Exercício/métodos
10.
Sensors (Basel) ; 22(23)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36502118

RESUMO

Fault detection and classification are crucial procedures for electric power distribution systems because they can minimize the occurrence of faults. The methods for fault detection and classification have become more problematic because of the significant expansion of distributed energy resources in distribution systems and the change in their currents due to the action of short-circuiting. In this context, to fill this gap, this study presents a robust methodology for short-circuit fault detection and classification with the insertion of distributed generation units. The proposal methodology progresses in two stages: in the former stage, the detection is based on the continuous analysis of three-phase currents, whose characteristics are extracted through maximal overlap discrete wavelet transform. In the latter stage, the classification is based on three fuzzy inference systems to identify the phases with disturbance. The short-circuit type is identified by counting the shorted phases. The algorithm for short-circuit fault detection and classification is developed in MATLAB programming environment. The methodology is implemented in a modified IEEE 34-bus test system and modeled in ATPDraw with three scenarios with and without distributed generation units and considering the following parameters: fault type (single-phase, two-phase, and three-phase), angle of incidence, fault resistance (high impedance fault and low impedance fault), fault location bus, and distributed generation units (synchronous generators and photovoltaic panels). The accuracy is greater than 94.9% for the detection and classification of short-circuit faults for more than 20,000 simulated cases.


Assuntos
Algoritmos , Eletricidade , Análise de Ondaletas
11.
Environ Res ; 195: 110885, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33609552

RESUMO

Extreme weather events, such as heatwaves, are becoming increasingly frequent, long-lasting and severe as global climate change continues, shaping marine biodiversity patterns worldwide. Increased risk of overheating and mortality across major taxa have been recurrently observed, jeopardizing the sustainability of ecosystem services. Molecular responses of species, which scale up to physiological and population responses, are determinant processes that modulate species sensitivity or tolerance to extreme weather events. Here, by integrating proteomic, fatty acid profiling and physiological approaches, we show that the tolerance of the intertidal ragworm Hediste diversicolor, a keystone species in estuarine ecosystems and an emergent blue bio-resource, to long-lasting heatwaves (24  vs 30 °C for 30 days) is shaped by calcium homeostasis, immune function and stability of fatty acid profiles. These features potentially enabled H. diversicolor to increase its thermal tolerance limit by 0.81 °C under the heatwave scenario and maintain survival. No growth trade-offs were detected, as wet weight remained stable across conditions. Biological variation of physiological parameters was lower when compared to molecular measures. Proteins showed an overall elevated coefficient of variation, although decreasing molecular variance under the heatwave scenario was observed for both proteins and fatty acids. This finding is consistent with the phenomenon of physiological canalization in extreme environments and contradicts the theory that novel conditions increase trait variation. Our results show that keystone highly valued marine polychaetes are tolerant to heatwaves, confirming the potential of H. diversicolor as a blue bio-resource and opening new avenues for sustainable marine aquaculture development.


Assuntos
Ecossistema , Poliquetos , Animais , Cálcio , Ácidos Graxos , Homeostase , Proteômica
12.
Appl Microbiol Biotechnol ; 105(23): 8881-8893, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34724083

RESUMO

The world economy is currently moving towards more sustainable approaches. Lignocellulosic biomass has been widely used as a substitute for fossil sources since it is considered a low-cost bio-renewable resource due to its abundance and continuous production. Compost habitats presenting high content of lignocellulosic biomass are considered a promising source of robust lignocellulose-degrading enzymes. Recently, several novel biocatalysts from different environments have been identified using metagenomic techniques. A key point of the metagenomics studies is the extraction and purification of nucleic acids. Nevertheless, the isolation of high molecular weight DNA from soil-like samples, such as compost, with the required quality for metagenomic approaches remains technically challenging, mainly due to the complex composition of the samples and the presence of contaminants like humic substances. In this work, a rapid and cost-effective protocol for metagenomic DNA extraction from compost samples composed of lignocellulosic residues and containing high content of humic substances was developed. The metagenomic DNA was considered as representative of the global environment and presented high quality (> 99% of humic acids effectively removed) and sufficient quantity (10.5-13.8 µg g-1 of compost) for downstream applications, namely functional metagenomic studies. The protocol takes about 4 h of bench work, and it can be performed using standard molecular biology equipment and reagents available in the laboratory. KEY POINTS/HIGHLIGHTS: • Metagenomic DNA was successfully extracted from compost samples rich in humic acids • The improved protocol was established by optimizing the cell lysis method and buffer • Complete removal of humic acids was achieved through the use of activated charcoal • The suitability of the DNA was proven by the construction of a metagenomic library.


Assuntos
Compostagem , Metagenômica , DNA/genética , Substâncias Húmicas/análise , Lignina , Solo
13.
J Thromb Thrombolysis ; 51(2): 545-551, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32936433

RESUMO

Both intravenous thrombolysis (IVT) and mechanical thrombectomy (MT) are evidence-based treatments for acute ischemic stroke (AIS) in selected cases. Recanalization may occur following IVT without the necessity of further interventions or requiring a subsequent MT procedure. IVT prior to MT (bridging-therapy) may be associated with benefits or hazards. We studied the retrieved clot area and degree of recanalization in patients undergoing MT or bridging-therapy for whom it was possible to collect thrombus material. We collected mechanically extracted thrombi from 550 AIS patients from four International stroke centers. Patients were grouped according to the administration (or not) of IVT before thrombectomy and the mechanical thrombectomy approach used. We assessed the number of passes for clot removal and the mTICI (modified Treatment In Cerebral Ischemia) score to define revascularization outcome. Gross photos of each clot were taken and the clot area was measured with ImageJ software. The non-parametric Kruskal-Wallis test was used for statistical analysis. 255 patients (46.4%) were treated with bridging-therapy while 295 (53.6%) underwent MT alone. By analysing retrieved clot area, we found that clots from patients treated with bridging-therapy were significantly smaller compared to those from patients that underwent MT alone (H1 = 10.155 p = 0.001*). There was no difference between bridging-therapy and MT alone in terms of number of passes or final mTICI score. Bridging-therapy was associated with significantly smaller retrieved clot area compared to MT alone but it did not influence revascularization outcome.


Assuntos
Fibrinolíticos/uso terapêutico , AVC Isquêmico/terapia , Trombólise Mecânica/métodos , Trombose/terapia , Ativador de Plasminogênio Tecidual/uso terapêutico , Feminino , Fibrinolíticos/administração & dosagem , Humanos , AVC Isquêmico/patologia , Masculino , Estudos Prospectivos , Terapia Trombolítica/métodos , Trombose/patologia , Ativador de Plasminogênio Tecidual/administração & dosagem , Resultado do Tratamento
14.
J Environ Manage ; 296: 113255, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34280837

RESUMO

Sewage sludge (SS) is a global environmental, social, and economic problem that requires a sustainable management approach. Still, the production of other industrial wastes, such as lime mud (LM), has recently gained considerable attention to avoid landfilling. This work aims to present a new approach for converting SS and LM into value-added products within the circular economy perspective. In particular, the effect of LM and calcined lime mud (CLM) as drying adjuvants and SS sanitation agents are investigated. Two out of three SS samples show Escherichia coli contamination above the Portuguese limit established for soil application, while no Salmonella spp. was detected in the searched samples. The addition of CLM to SS in a ratio between 0.05 and 0.15 g CLM/gwb, lead to complete elimination of the microbiological contamination in almost all cases. Contrarily, the use of LM does not seem efficient to act as a sanitation agent. Both LM and CLM show a positive impact on the drying process when compared to the raw SS, increasing the drying rate, and reducing the drying time. The most favourable drying conditions to maximize the drying rate and minimize the drying time (until 30% of moisture) are 130 °C, 0.15 g adj/gwb, and 2.5 mm of plate thickness. The thermal treatment (100 and 130 °C) without adjuvants reduces the microbiological contamination below the legal limit. Overall, a beneficial effect is observed by adding CLM to SS, open the possibility of producing a safer organic soil improver.


Assuntos
Descontaminação , Esgotos , Compostos de Cálcio , Óxidos
15.
Sensors (Basel) ; 20(16)2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32784603

RESUMO

Electronic skin (e-skin), which is an electronic surrogate of human skin, aims to recreate the multifunctionality of skin by using sensing units to detect multiple stimuli, while keeping key features of skin such as low thickness, stretchability, flexibility, and conformability. One of the most important stimuli to be detected is pressure due to its relevance in a plethora of applications, from health monitoring to functional prosthesis, robotics, and human-machine-interfaces (HMI). The performance of these e-skin pressure sensors is tailored, typically through micro-structuring techniques (such as photolithography, unconventional molds, incorporation of naturally micro-structured materials, laser engraving, amongst others) to achieve high sensitivities (commonly above 1 kPa-1), which is mostly relevant for health monitoring applications, or to extend the linearity of the behavior over a larger pressure range (from few Pa to 100 kPa), an important feature for functional prosthesis. Hence, this review intends to give a generalized view over the most relevant highlights in the development and micro-structuring of e-skin pressure sensors, while contributing to update the field with the most recent research. A special emphasis is devoted to the most employed pressure transduction mechanisms, namely capacitance, piezoelectricity, piezoresistivity, and triboelectricity, as well as to materials and novel techniques more recently explored to innovate the field and bring it a step closer to general adoption by society.


Assuntos
Membros Artificiais , Robótica , Dispositivos Eletrônicos Vestíveis , Eletrônica , Humanos , Pressão
16.
J Environ Manage ; 261: 109944, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32148252

RESUMO

This study aims to investigate the sewage sludge (SS) drying process by incorporating a by-product formed in the pulp and paper industry (green liquor dregs - GLD) as drying adjuvant. Through an innovative approach, the drying kinetics was modelled, and the final dried product was tested for soil applications. After the characterization phase, small cylinders of SS without and with 0.15 g GLD g SS-1wb (SS_GLD) were dried in isothermal conditions at 70, 100, and 130 °C. The experimental data were fitted by Fick's second law and thin-layer models, and good results were achieved in both cases (R2 > 0.98 and RMSE <0.05). Although only a slight improvement was observed, the best conditions for drying biosolids were found with the addition of GLD at 130 °C, where the drying rate was 30.88 gH2O kg-1 SSwb min-1. In this condition, a decrease of 8% in the energy required for moisture evaporation was observed. Regarding the phytotoxicity tests with Lepidium sativum L. (garden cress), 60% improvement in EC50 was noticed for the sample with GLD when compared to the raw SS. The dried product SS_GLD complied with the regulations for soil applications regarding the potentially toxic metals (Cr, Ni, Cu, Pb, Zn, and Cd), and promoted an increase in soil organic matter and pH. However, further and in-depth studies should be conducted to assess the potential of SS_GLD application in agricultural soil.


Assuntos
Metais Pesados , Poluentes do Solo , Biossólidos , Desidratação , Humanos , Esgotos , Solo
17.
J Biol Chem ; 293(6): 1957-1975, 2018 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-29284679

RESUMO

Alzheimer's disease (AD) is a disabling and highly prevalent neurodegenerative condition, for which there are no effective therapies. Soluble oligomers of the amyloid-ß peptide (AßOs) are thought to be proximal neurotoxins involved in early neuronal oxidative stress and synapse damage, ultimately leading to neurodegeneration and memory impairment in AD. The aim of the current study was to evaluate the neuroprotective potential of mesenchymal stem cells (MSCs) against the deleterious impact of AßOs on hippocampal neurons. To this end, we established transwell cocultures of rat hippocampal neurons and MSCs. We show that MSCs and MSC-derived extracellular vesicles protect neurons against AßO-induced oxidative stress and synapse damage, revealed by loss of pre- and postsynaptic markers. Protection by MSCs entails three complementary mechanisms: 1) internalization and degradation of AßOs; 2) release of extracellular vesicles containing active catalase; and 3) selective secretion of interleukin-6, interleukin-10, and vascular endothelial growth factor to the medium. Results support the notion that MSCs may represent a promising alternative for cell-based therapies in AD.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Vesículas Extracelulares/metabolismo , Hipocampo/citologia , Células-Tronco Mesenquimais/citologia , Neurônios/metabolismo , Estresse Oxidativo , Sinapses/metabolismo , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/química , Animais , Células Cultivadas , Técnicas de Cocultura , Vesículas Extracelulares/genética , Hipocampo/metabolismo , Humanos , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Masculino , Células-Tronco Mesenquimais/metabolismo , Neurônios/citologia , Ratos , Ratos Wistar , Fator A de Crescimento do Endotélio Vascular/metabolismo
18.
Phys Chem Chem Phys ; 21(47): 26111-26116, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31748770

RESUMO

Intramolecular non-covalent interactions determine the conformational preferences of many molecules, and their understanding is relevant for a proper description of molecular structure. Here, by using rotational spectroscopy in combination with quantum chemistry calculations, we show that intramolecular dispersion forces involving a three-carbon substituent influence the relative energies and conformational landscape of the three monoterpenoids carvone, limonene and perillaldehyde. New equatorial and axial conformers have been identified for all three molecules. Comparison of experimental data with ab initio and density functional calculations shows that axial conformers are stabilised by dispersion interactions between the cyclohexene ring and the isopropenyl group of the monoterpenoids, and that an accurate account of these interactions is challenging for theoretical methods. This work demonstrates the potential of rotational spectroscopy for investigating non-covalent interactions and provides critical benchmarks for theory. Our results will inform future investigations of axial/equatorial isomerism and impact understanding of intramolecular dispersion in larger species.

19.
Sensors (Basel) ; 19(4)2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30795531

RESUMO

Electronic skin (e-skin) is pursued as a key component in robotics and prosthesis to confer them sensing properties that mimic human skin. For pressure monitoring, a great emphasis on piezoresistive sensors was registered due to the simplicity of sensor design and readout mechanism. For higher sensitivity, films composing these sensors may be micro-structured, usually by expensive photolithography techniques or low-cost and low-customizable molds. Sensors commonly present different sensitivities in different pressure ranges, which should be avoided in robotics and prosthesis applications. The combination of pressure sensing and temperature is also relevant for the field and has room for improvement. This work proposes an alternative approach for film micro-structuration based on the production of highly customizable and low-cost molds through laser engraving. These bimodal e-skin piezoresistive and temperature sensors could achieve a stable sensitivity of -6.4 × 10-3 kPa-1 from 1.6 kPa to 100 kPa, with a very robust and reproducible performance over 27,500 cycles of objects grasping and releasing and an exceptionally high temperature coefficient of resistance (TCR) of 8.3%/°C. These results point toward the versatility and high benefit/cost ratio of the laser engraving technique to produce sensors with a suitable performance for robotics and functional prosthesis.


Assuntos
Membros Artificiais , Técnicas Biossensoriais/métodos , Robótica/métodos , Dispositivos Eletrônicos Vestíveis , Humanos , Lasers , Pressão , Implantação de Prótese/métodos , Temperatura
20.
J Environ Manage ; 238: 451-459, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30875643

RESUMO

Phosphorus scarcity has become a significant issue in the European Union (EU) during 21st Century, due to its relevance as an irreplaceable macronutrient for life, and because of the total dependency of EU regarding imports. This work aims to evaluate the phosphorus recovery by adsorption in batch and fixed-bed column, using a thermally modified eggshell as an adsorbent. The screening phase revealed that calcined eggshell at 700 °C (CES700) is the most suitable material compared with the other thermally modified eggshells tested. Thus, CES700 was characterized regarding the specific surface area, pore volume, zero-point charge pH, total dissolved solids and organic matter. The influence of pH and adsorbent dosage was investigated in batch conditions. Langmuir-Freundlich model described the equilibrium data and the maximum adsorption capacity was about 39 mg P-PO4/g. The kinetics follows a pseudo-first order model, with constants between 0.063 and 0.224 min-1. Fixed-bed studies indicated that increasing fluid superficial velocity and feed concentration led to an early saturation of the adsorbent. Yoon-Nelson, Thomas and Bohard-Adams empirical models properly adjusted the breakthrough curves with R2 ≥ 0.98. Germination tests using CES700 loaded with phosphate revealed a germination index of 120 and 124% to 48 and 72 h, respectively. CES700 is statically better than the other tested materials, which opens the possibility of its use as fertilizer. This study showed that the developed material, CES700, can be applied in batch or fixed-bed processes to recover phosphate ions from liquid effluents, and the loaded adsorbent has potential to be further used as fertilizer.


Assuntos
Fosfatos , Poluentes Químicos da Água , Adsorção , Animais , Casca de Ovo , Concentração de Íons de Hidrogênio , Cinética , Fósforo , Soluções , Água
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