Modelling the transport of lactic acid, sodium chloride and reducing sugars in carrot slices submerged in brines - Part II. Multivariate approach

In this paper following a methodology of (nested) increasing model complexity, it was found that the apparent diffusivities and the partition coefficients associated with the transport of lactic acid and sodium chloride from the brine into carrot slices submerged therein can be modelled as functions of temperature using Arrhenius-type relationships and as exponential functions of the initial concentrations of either solute in the brine. The apparent diffusivities in the free liquid phase, in the case of transport of reducing sugars from the carrots to the brine, are assumed to vary with time as a consequence of the bursting of the carrot cells following first-order kinetics on both the concentration of intact cells and dead cells. In this case, and following a similar methodology, the apparent diffusivity in the free liquid phase, the pseudo-firstorder rate constant for cell bursting, and the partition coefficients are well modelled when they are all assumed to follow temperature dependencies given by Arrhenius-type relationships; the dependencies on the initial concentration of salt in the brine were found not to be statistically significant. The underlying assumptions of normal distribution and constant variance were checked using plots of residuals, whereas the decision on the acceptable complexity of the nested models was taken based on the values of the F-distribution. The analysis developed is relevant for practical purposes because the multivariate models obtained in the form of correlations are simple functions of easily measured operating variables

Investigating Organic Colorants Across Time: Interdisciplinary Insights into the use of Madder, Indigo/Woad, and Weld in Historical Written Sources, Archaeological Textiles, and Ancient Polychromy

Organic dyes have been used from the earliest times to provide color primarily to textiles, but also as a colorant in painting. Such organic dyes could create a wealth of colors, depending on the availability and know-how of resources. These dyes are usually organic in nature, and primarily obtained from different plant sources. Unfortunately, the characterization of natural organic colorants in textiles and artworks is still a challenge. The difficulty of analyzing these materials is sometimes allied to the frequent impossibility of micro-sampling, and the frailty of the objects. Many techniques, such as HPLC (High-Performance Liquid Chromatography) and SERS (Surface-Enhanced Raman Spectroscopy), require the use of a micro-sample, which cannot be recovered after analysis. Moreover, the portable technique Fibre Optic Reflectance Spectroscopy (FORS) can present some challenges in distinguishing between different dye sources belonging to the same molecular family, such as anthraquinone reds. Although no one technique alone can unravel the world of natural dyes, a multi-analytical approach has proven to be far more effective for their identification and characterization. In the present article, we intend to share insights into three different perspectives and types of source material for the study of the use of organic colorants in ancient and historical times: The first case study presents an 18th-century historical recipe for dyeing textiles, the second case study presents a study of preserved archaeological textiles from Nubia, while the third case study presents the use of organic colorants for the polychromy of ancient Greco-Roman iconography

Neanderthal Subsistence in Portugal: What Evidence?

A total of 270 Middle Palaeolithic sites are recorded in the Portuguese Archaeology Archive. However, only a few were systematically excavated, present valuable archaeological information and show reliable absolute date results. Amongst them, 13 archaeological sites yielded animal remains, but most of these assemblages are of indeterminate origin, or due to natural or carnivore accumulations. Therefore, only three sites have faunal assemblages produced by hominin activity: Gruta Nova da Columbeira, Gruta da Figueira Brava and Gruta da Oliveira. The last two caves are the ones currently being studied for a funded research project conducted in UCL Institute of Archaeology, therefore, providing substantial information on Neanderthal subsistence and palaeoenvironment in Portugal

Removal of amitriptyline from simulated gastric and intestinal fluids using activated carbons

In this work, the adsorption behavior of a tricyclic antidepressant, amitriptyline hydrochloride, onto several activated carbons (ACs) is reported. The adsorption was done using in vitro simulated gastric and intestinal fluid at 37◦C to test the performance of the carbons as treatment in overdose cases. The tested materials were one commercial AC (carbomix) and two ACs produced in our laboratory. The highest adsorption capacity was achieved by carbomix, followed by the laboratory-made carbons that still have a very good performance with adsorption capacity up to 120 and 100 mg/g for the gastric and intestinal fluids, respectively

Total Tumor Load Assessed by One-Step Nucleic Acid Amplification Assay as an Intraoperative Predictor for Non-Sentinel Lymph Node Metastasis in Breast Cancer

BACKGROUND: This study aimed to determine the relationship between CK19 mRNA copy number in sentinel lymph nodes (SLN) assessed by one-step nucleic acid amplification (OSNA) technique, and non-sentinel lymph nodes (NSLN) metastization in invasive breast cancer. A model using total tumor load (TTL) obtained by OSNA technique was also constructed to evaluate its predictability. METHODS: We conducted an observational retrospective study including 598 patients with clinically T1-T3 and node negative invasive breast cancer. Of the 88 patients with positive SLN, 58 patients fulfill the inclusion criteria. RESULTS: In the analyzed group 25.86% had at least one positive NSLN in axillary lymph node dissection. Univariate analysis showed that tumor size, TTL and number of SLN macrometastases were predictive factors for NSLN metastases. In multivariate analysis just the TTL was predictive for positive NSLN (OR 2.67; 95% CI 1.06-6.70; P = 0.036). The ROC curve for the model using TTL alone was obtained and an AUC of 0.805 (95% CI 0.69-0.92) was achieved. For TTL >1.9 × 105 copies/μL we got 73.3% sensitivity, 74.4% specificity and 88.9% negative predictive value to predict NSLN metastases. CONCLUSION: When using OSNA technique to evaluate SLN, NSLN metastases can be predicted intraoperatively. This prediction tool could help in decision for axillary lymph node dissection.info:eu-repo/semantics/publishedVersio

Modelling the transport of lactic acid, sodium chloride and reducing sugars in carrot slices submerged in brines - Part I. Univariate approach

The transport phenomena pertaining to the independent diffusion of lactic acid and sodium chloride from a brine into carrot slices submerged therein, and of reducing sugars in the opposite direction, were experimentally studied at various temperatures and initial concentrations of salt and acid in the brine. The data sets obtained at each combination of temperature and initial concentration of the brine were independently fit to three analytical models derived from just principles on three alternative mechanisms postulated for the time-variation of the diffusivity. Incremental sum of squares analyses have shown that the diffusion of acid and salt into the carrots is well described by a constant diffusivity, whereas the diffusion of reducing sugars out of the carrots is well described by a diffusivity undergoing a sigmoidal variation with time. This sigmoidal variation may be explained by the assumption that the bursting of the carrot cells is simultaneously proportional to the fraction of intact cells and the fraction of burst cells of the carrot material. The analysis developed is relevant because it allows an approximate prediction of the rates of acid and salt intake, as well as the release rates of reducing sugars, pertaining to bried carrot slices, the basic processes that occur during manufacture of lactic acid carrot pickles

The knowledge of master dyers revealed by HPLC-DAD and UHPLC-HRMS/MS

UIDB/00749/2020 UIDP/00749/2020This work provides new knowledge on natural yellows used in Iran. Seven biological sources were selected based on interviews with dye masters in Isfahan workshops (Iran). Delphinium semibarbatum, Eremostachys laevigata, Prangos ferulacea, Morus alba, Pistacia vera, Punica granatum, and Vitis vinifera are currently used in these workshops. Aiming to study the dye composition of wool samples dyed with the extracts of the selected biological sources and the changes induced by the dyeing procedures in the original chemical composition of the plant extract, raw materials and dyed wool (by us and in the workshops) were analyzed by HPLC–DAD and UHPLC–HRMS/MS. The main yellows for E. laevigata are luteolin-O-glycosides. In the other plant sources, the main chromophores are based on 3-O-glycosides of kaempferol, quercetin, and isorhamnetin. In pistachio hulls, myricitin derivatives were detected and we propose their use as markers. Generally, the solutions extracted from the wool displayed a higher amount of more polar compounds, but also a higher amount of aglycones. Importantly, the chromatographic profiles of the samples we prepared compared well with 17th c. yellows in Persian carpets, and therefore can be considered highly characterized references for the study of Persian yellowThis work provides new knowledge on natural yellows used in Iran. Seven biological sources were selected based on interviews with dye masters in Isfahan workshops (Iran). Delphinium semibarbatum, Eremostachys laevigata, Prangos ferulacea, Morus alba, Pistacia vera, Punica granatum, and Vitis vinifera are currently used in these workshops. Aiming to study the dye composition of wool samples dyed with the extracts of the selected biological sources and the changes induced by the dyeing procedures in the original chemical composition of the plant extract, raw materials and dyed wool (by us and in the workshops) were analyzed by HPLC–DAD and UHPLC–HRMS/MS. The main yellows for E. laevigata are luteolin-O-glycosides. In the other plant sources, the main chromophores are based on 3-O-glycosides of kaempferol, quercetin, and isorhamnetin. In pistachio hulls, myricitin derivatives were detected and we propose their use as markers. Generally, the solutions extracted from the wool displayed a higher amount of more polar compounds, but also a higher amount of aglycones. Importantly, the chromatographic profiles of the samples we prepared compared well with 17th c. yellows in Persian carpets, and therefore can be considered highly characterized references for the study of Persian yellows.publishersversionpublishe

Estudos de adsorção de fluoxetina por carvões activados antes e após modificação química

O estudo cinético realizado demonstrou que o equilíbrio é rapidamente atingido, na maioria dos casos após 60 minutos de contacto, pelo que se considerou um tempo óptimo de 120 minutos para realizar os ensaios de adsorção. Os materiais de carbono testados apresentam uma vasta gama de características com ponto de carga zero entre 3 e 12, área aparente BET (ABET) entre 780 e 2500m2/g e volume poroso (Vp, determinado pelo método s) entre 0.3 e 1.1cm3/g. Na generalidade dos casos a quantidade adsorvida a pH=7.5 é maior do que a adsorvida a pH=1.2 devido às interacções electroestáticas entre a molécula da fluoxetina, que aos valores de pH referidos está na forma ionizada e portanto com carga positiva, e a carga média da superfície que é sempre mais favorável a pH=7.5. Ao comparar adsorventes com valores aproximadamente iguais de ponto de carga zero (pcz) podemos verificar que o volume poroso determina nestes casos a capacidade máxima de adsorção, por exemplo Carbomix vs Maxsorb30. Podemos também verificar que a capacidade máxima de adsorção aumenta à medida que o valor de pcz dos materiais diminui. Os ensaios demonstraram que os materiais testados possuem potencial para efectuarem a adsorção da fluoxetina tendo-se conseguido obter quantidades adsorvidas superiores aos referenciados na literatura. Podemos também concluir que as fibras de carbono activadas utilizadas possuem um comportamento distinto do observado para as amostras de carvões activados, nomeadamente no que diz respeito à influência das interacções electrostáticas na adsorção de fluoxetina. Aparentemente no caso dos carvões activados o mecanismo de adsorção depende em maior escala deste tipo de interacções enquanto que no caso das fibras de carbono activadas e factor mais relevante será as interacções de natureza dispersiva. A modificação dos carvões activados por oxidação leva a um incremento da quantidade máxima adsorvida de fluoxetina justificado pela natureza ácida da mesma

Method for promoting in-situ hydrochar porosity in hydrothermal carbonization of almond shells with air activation

In this work, a new procedure for in situ hydrochar activation during hydrocarbonization of biomass (almond shell) is proposed. This approach suggests the addition of a controlled oxidizing gas stream (i.e. synthetic air) during the process for different periods of time, in order to promote the hydrochar porosity. Characterization of prepared materials revealed a noticeable development of porosity with apparent surfaces areas up to 320 m2/g. A highlighting variety of functional acid groups especially sensitive to air supply time was confirmed by surface chemistry analysis. Promising preliminary results show the effectiveness of this alternative approach synthesis strategy in converting a low value lignocellulosic biomass into porous materials with potential applications such as adsorption, electrical energy and gas storage or catalysis

Prognostic impact of hemoglobin drop during hospital stay in patients with acute coronary syndromes

INTRODUCTION: Bleeding is currently the most common non-cardiac complication of therapy in patients with acute coronary syndromes (ACS), and may itself be associated with adverse outcomes. The aim of this study was to determine the effect of hemoglobin drop during hospital stay on outcome among patients with ACS. METHODS: Using Cox proportional-hazards modeling, we examined the association between hemoglobin drop and death or myocardial infarction (MI) at 6 months in 1172 patients admitted with ACS to an intensive cardiac care unit. Patients were stratified according to quartiles of hemoglobin drop: Q1, or = 2.4 g/dL. We also identified independent predictors of increased hemoglobin drop (> or =2.4 g/dL) using multivariate logistic regression analysis. RESULTS: Median nadir hemoglobin concentration was 1.5 g/dL lower (IQR 0.8-2.3) compared with baseline hemoglobin (p < 0.0001). Independent predictors of increased hemoglobin drop included older Sage, renal dysfunction, lower weight, and use of thrombolytic therapy, glycoprotein IIb/IIIa inhibitors, nitrates, and percutaneous coronary intervention. Higher levels of hemoglobin drop were associated with increased rates of 6-month mortality (8.0% vs. 9.4% vs. 9.6% vs. 15.7%; p for trend = 0.014) and 6-month death/ MI (12.4% vs. 17.0% vs. 17.2% vs. 22.1%; p for trend = 0.021). Using Q1 as reference group, the adjusted hazard ratio (HR) for 6-month mortality and 6-month death/MI among patients in the highest quartile of hemoglobin drop was 1.83 (95% confidence interval [CI] 1.08-3.11; p = 0.026) and 1.60 (95% CI 1.04-2.44; p = 0.031) respectively. Considered as a continuous variable, the adjusted HR for 6-month mortality was 1.16 (95% CI 1.01-1.32; p = 0.030) per 1 g/dL increase in hemoglobin drop. CONCLUSIONS: A decrease in hemoglobin frequently occurs during hospitalization for ACS and is independently associated with adverse outcomes