2023
Authors
Coelho, L; Glotsos, D; Reis, S;
Publication
BIOENGINEERING-BASEL
Abstract
2023
Authors
Yang, CY; Menz, C; Reis, S; Machado, N; Santos, JA; Torres-Matallana, JA;
Publication
AGRONOMY-BASEL
Abstract
Vine phenology modelling is increasingly important for winegrowers and viticulturists. Model calibration is often required before practical applications. However, when multiple models and optimization methods are applied for different varieties, it is rarely known which factor tends to mostly affect the calibration results. We mainly aim to investigate the main source of the variability in the modelling errors for the flowering timings of two important varieties of vine in the Douro Demarcated Region (DDR) of Portugal; this is based on five phenology model simulations that use optimal parameters and that are estimated by three optimization algorithms (MLE, SA and SCE-UA). Our results indicate that the main source of the variability in calibration can be affected by the initially assumed parameter boundary. Restricting the initial parameter distribution to a narrow range impedes the algorithm from exploring the full parameter space and searching for optimal parameters. This can lead to the largest variation in different models. At an identified appropriate boundary, the difference between the two varieties represents the largest source of uncertainty, while the choice of algorithm for calibration contributes least to the overall uncertainty. The smaller variability among different models or algorithms (tools for analysis) compared to between different varieties could indicate the overall reliability of the calibration. All optimization algorithms show similar results in terms of the obtained goodness-of-fit: the RMSE (MAE) is 5-6 (4-5) days with a negligible mean bias and moderately good R-2 (0.5-0.6) for the ensemble median predictor. Nevertheless, a similar predictive performance can result from differently estimated parameter values, due to the equifinality or multi-modal issue in which different parameter combinations give similar results. This mainly occurs for models with a non-linear structure compared to those with a near-linear one. Yet, the former models are found to outperform the latter ones in predicting the flowering timing of the two varieties in the DDR. Overall, our findings highlight the importance of carefully defining the initial parameter boundary and decomposing the total variance of prediction errors. This study is expected to bring new insights that will help to better inform users about the importance of choice when these factors are involved in calibration. Nonetheless, the importance of each factor can change depending on the specific situation. Details of how the optimization methods are applied and of the continuous model improvement are important.
2023
Authors
Leite, A; Queirós, C; M.G. Silva, A;
Publication
Exploring Chemistry with Pyridine Derivatives
Abstract
2023
Authors
Queiros, C; Leite, A; Moura, NMM; Cerqueira, AFR; Serra, VV; Neves, MGPMS; Tome, AC; Silva, AMG;
Publication
DYES AND PIGMENTS
Abstract
The design of novel molecular structures with tunable photophysical properties is an important research field for many applications including optoelectronics, sensing and bioimaging. Porphyrin and rhodamine/rosamine derivatives are among the most studied and relevant chemosensors and imaging probes due to their attractive photophysical properties, such as high absorption coefficients and long emission wavelengths. In this work, we present the synthesis and the structural characterization of a new porphyrin-rosamine conjugate H2P3 and its related triarylmethane precursors H2P1 and H2P2. The photophysical properties of H2P1, H2P2 and H2P3, and their ability to chelate iron(III) and copper(II) ions, were evaluated by absorption and emission spectroscopy. The formation of copper(II) complexes was confirmed by electron paramagnetic resonance (EPR), which also allowed the detection of an intense and stable radical signal for the free-base H2P3. Further studies involving the addition of the 2,2,6,6-tetramethylpiperidine spin trap to derivatives H2P1, H2P2 and H2P3, showed that only H2P3 gives rise to an EPR detectable signal due to a strong generation of singlet oxygen.
2023
Authors
Moscoso, FG; Queios, C; Gonzalez, P; Lopes-Costa, T; Silva, AMG; Pedrosa, JM;
Publication
MOLECULES
Abstract
We report the use of a carboxylated pyrrolidine-fused chlorin (TCPC) as a fluorescent probe for the determination of glutathione (GSH) in 7.4 pH phosphate buffer. TCPC is a very stable, highly emissive molecule that has been easily obtained from meso-tetrakis(4-methoxycarbonylphenyl) porphyrin (TCPP) through a 1,3-dipolar cycloaddition approach. First, we describe the coordination of TCPC with Hg(II) ions and the corresponding spectral changes, mainly characterized by a strong quenching of the chlorin emission band. Then, the TCPC-Hg2+ complex exhibits a significant fluorescence turn-on in the presence of low concentrations of the target analyte GSH. The efficacy of the sensing molecule was tested by using different TCPC:Hg2+ concentration ratios (1:2, 1:5 and 1:10) that gave rise to sigmoidal response curves in all cases with modulating detection limits, being the lowest 40 nM. The experiments were carried out under physiological conditions and the selectivity of the system was demonstrated against a number of potential interferents, including cysteine. Furthermore, the TCPC macrocycle did not showed a significant fluorescent quenching in the presence of other metal ions.
2023
Authors
Neves, JAC; Roseira, J; Queirós, P; Sousa, HT; Pellino, G; Cunha, MF;
Publication
GUT
Abstract
Objective Endoscopy is healthcare's third largest generator of medical waste in hospitals. This prospective study aimed to measure a single unit's waste carbon footprint and perform a pioneer intervention towards a more sustainable endoscopy practice. The relation of regulated medical waste (RMW; material fully contaminated with blood or body fluids or containing infectious agents) versus landfill waste (non-recyclable material not fully contaminated) may play a critical role. Design In a four-stage prospective study, following a 4-week observational audit with daily weighing of both waste types (stage 1), stage 2 consisted of a 1-week intervention with team education of waste handling. Recycling bins were placed in endoscopy rooms, landfill and RMW bins were relocated. During stages 3 (1 month after intervention) and 4 (4 months after intervention), daily endoscopic waste was weighed. Equivalence of 1 kg of landfill waste to 1 kg carbon dioxide equivalent (CO2e) and 1 kg of RMW to 3kgCO(2e) was assumed. Paired samples t-tests for comparisons. Results From stage 1 to stage 3, mean total waste and RMW were reduced by 12.9% (p=0.155) and 41.4% (p=0.010), respectively, whereas landfill (p=0.059) and recycling waste increased (paper: p=0.001; plastic: p=0.007). While mean endoscopy load was similar (46.2 vs 44.5, p=0.275), a total decrease of CO2e by 31.6% (138.8kgCO(2e)) was found (mean kgCO(2e)109.7 vs 74.9, p=0.018). The annual reduction was calculated at 1665.6kgCO(2e). All these effects were sustained 4 months after the intervention (stage 4) without objections by responsible endoscopy personnel. Conclusion In this interventional study, applying sustainability measures to a real-world scenario, RMW reduction and daily recycling were achieved and sustained over time, without compromising endoscopy productivity.
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