Findings of archaeological textiles and fibres in Northern Iberia are extremely rare. The occurrence of a set of textile fragments, dated between the 14th and 16th centuries CE at the Pambre castle ...(Palas de Rei, Lugo, Spain) is exceptional. The original stone roof of the southeastern tower was intact. The dark, cold and moist conditions inside the tower favoured the preservation of a unique series of waterlogged textile remains. In addition, a set of pseudomorphs preserved by mineral replacement were recovered from the east edge of the north wing in the main hall of the castle. Fibres have been identified using optical and scanning electron microscopy (SEM), and they have been chemically characterised using Energy Dispersive X-Ray Spectroscopy (EDX). We also performed analytical pyrolysis-GC-MS (Py-GC-MS) and thermally assisted hydrolysis and methylation (THM-GC-MS) of the wool fabrics and pseudomorphs to assess their state of degradation and the presence of chemical markers associated to the use of these textile remains. High performance liquid chromatography with diode array detection (HPLC-DAD-MS) and ultra-high performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS/MS) analysis were applied on wool fabrics to identify the chemical markers of dyes but without success. To expand the information related to raw material identification and the technical aspects of the fabrics, further evidence such as adherences identified as opal phytoliths, seeds, and insect remains associated to wool fabrics were examined. These findings offer a unique glimpse into the clothing dated to the end of the Medieval period, and its life-cycle. Wool scraps were probably part of at least two different garments, whereas the mineralised textiles probably formed part of at least two brigandines which were made of bast fibres, flax, or hemp.
•The study offers a glimpse into clothing between the 14th and 16th centuries CE.•An interdisciplinary approach was designed to address textile biographies.•Wool fabrics were subjected to successive alterations that changed their morphology.•Metallic pseudomorphs belong to one or, more likely, several brigandines.
This work describes the efficient and selective reductive depolymerization of PET, PBT, PCL, PLA and PDO plastic waste into value-added compounds and fuels, including 1,6-hexanediol, xylene and ...propane, catalyzed by the eco-friendly, cheap and air-stable dioxomolybdenum complex MoO
2
Cl
2
(H
2
O)
2
using silanes as reducing agents. The catalyst MoO
2
Cl
2
(H
2
O)
2
can be used in at least 8 catalytic cycles in the reductive depolymerization of PCL with excellent activity and the catalytic system PMHS/MoO
2
Cl
2
(H
2
O)
2
was successfully applied in the production of propane from the reductive depolymerization of PLA on a gram scale. Moreover, this method was also efficiently applied in the selective reduction of a PCL, PLA and PET mixture.
Several types of PCL, PLA, PDO, PET and PBT plastic waste were efficiently converted into value-added compounds and fuels catalyzed by MoO
2
Cl
2
(H
2
O)
2
.
Biofluid metabolomics is a very appealing tool to increase the knowledge associated with pathophysiological mechanisms leading to better and new therapies and biomarkers for disease diagnosis and ...prognosis. However, due to the complex process of metabolome analysis, including the metabolome isolation method and the platform used to analyze it, there are diverse factors that affect metabolomics output. In the present work, the impact of two protocols to extract the serum metabolome, one using methanol and another using a mixture of methanol, acetonitrile, and water, was evaluated. The metabolome was analyzed by ultraperformance liquid chromatography associated with tandem mass spectrometry (UPLC-MS/MS), based on reverse-phase and hydrophobic chromatographic separations, and Fourier transform infrared (FTIR) spectroscopy. The two extraction protocols of the metabolome were compared over the analytical platforms (UPLC-MS/MS and FTIR spectroscopy) concerning the number of features, the type of features, common features, and the reproducibility of extraction replicas and analytical replicas. The ability of the extraction protocols to predict the survivability of critically ill patients hospitalized at an intensive care unit was also evaluated. The FTIR spectroscopy platform was compared to the UPLC-MS/MS platform and, despite not identifying metabolites and consequently not contributing as much as UPLC-MS/MS in terms of information concerning metabolic information, it enabled the comparison of the two extraction protocols as well as the development of very good predictive models of patient’s survivability, such as the UPLC-MS/MS platform. Furthermore, FTIR spectroscopy is based on much simpler procedures and is rapid, economic, and applicable in the high-throughput mode, i.e., enabling the simultaneous analysis of hundreds of samples in the microliter range in a couple of hours. Therefore, FTIR spectroscopy represents a very interesting complementary technique not only to optimize processes as the metabolome isolation but also for obtaining biomarkers such as those for disease prognosis.
Weld (Reseda luteola) was one of the main sources of yellow dyes used for dyeing textiles and to prepare artists’ pigments in Europe until the 19th century. For the first time, this work explores the ...technology of preparing weld lake pigments in the 19th century by Winsor & Newton (W&N), a renowned supplier of artists’ materials. Five recipes were discovered in the W&N 19th century Archive Database and reconstructed in the laboratory. W&N was extracting weld in neutral and basic media, and preparing the insoluble lake by complexation with Al3+ in the form of alum (KAl(SO4)2•12H2O) or hydrated alumina (Al(OH)3). Five yellow lake pigments were successfully obtained and characterized by High-Performance Liquid Chromatography-Diode Array Detector (HPLC-DAD) and Fourier Transform Infrared Spectroscopy (FTIR). Their chromatographic profiles display as main yellows, luteolin 7-O-glucoside (Lut-7-O-glu) or both Lut-7-O-glu plus luteolin 3′,7-O-glucoside (Lut-3’,7-O-glu). In two of the processes, the presence of gypsum (CaSO4•2H2O) was unequivocally detected by FTIR, being formed as a by-product. This work offers the first identification of weld lake pigments’ characteristic infrared bands. The W&N Database proved again to be a unique source of information on 19th-century artists’ materials and their commercial preparation. The knowledge gain is essential to ensure effective conservation and authentication procedures.
Several methods have been used to tailor nanomaterials structure and properties. Sometimes, slight changes in the structure outcomes expressive improvements in the optical and photocatalytic ...properties of semiconductor nanoparticles. In this context, the influence of the metal doping and the morphology on a catalyst performance was studied in this work. Here, ruthenium doped titanate nanotubes (RuTNT) were synthesised for the first time using an amorphous Ru-containing precursor. Afterwards, the photocatalytic performance of this sample was compared to the one obtained for ruthenium titanate nanowires (RuTNW), recently reported. Two samples, RuTNW and RuTNT, were produced using the same Ru-containing precursor but distinct hydrothermal methodologies. The powders were structural, morphological and optical characterized by X-ray diffraction and fluorescence, transmission electron microscopy, Raman, X-ray photoelectron and photoluminescence spectroscopies. Distinct variations on the structural and optical properties of the RuTNT and RuTNW nanoparticles, due to ruthenium incorporation were observed. Their potential use as photocatalysts was evaluated on the hydroxyl radical photo-assisted production. Both samples were catalytic for this reaction, presenting better performances than the pristine counterparts, being RuTNT the best photocatalyst. Subsequently, the degradation of two emergent pollutants, caffeine and sulfamethazine, was studied. RuTNT demonstrated to be better photocatalyst than RuTNW for caffeine but identical performances were obtained for sulfamethazine. For both catalysts, the degradation mechanism of the pollutants was explored through the identification and quantification of the intermediate compounds produced and several differences were found. This indicates the importance of the structural and morphological aspects of a material on its catalytic performance.
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The DABCO-catalyzed 3 + 3 annulation between 3-nitro-2
-chromenes and benzyl 2,3-butadienoate has been developed as a route to 5
-chromeno3,4-
pyridine derivatives. Under optimal reaction conditions, ...5
-chromeno3,4-
pyridines incorporating two allenoate units were obtained in moderate to good yields (30-76%). The same type of transformation could be carried out using butynoates as allene surrogates. Mechanistic studies by mass spectrometry allowed the identification of the key intermediates involved in the reaction mechanism. The reported synthetic methodology represents an entirely new approach for the synthesis of the 5
-chromeno3,4-
pyridine core structure based on allene chemistry.
The synthesis of novel types of furanosyl nucleoside analogues, namely N‐(benzyltriazolyl)methyl glucuronamide derivatives, N‐dodecyl glucuronamide‐based phenyltriazole nucleosides, and theobromine ...xylosyl 5′‐isonucleosides, as potential cholinesterase inhibitors is described herein. O‐Substituted and partially O‐substituted N‐propargyl glucuronamides, accessed from glucofuranurono‐6,3‐lactone, were engaged in CuI‐catalyzed cycloaddition with benzyl azide, whereas their N‐dodecyl uronamide counterparts were converted in three steps into glycosyl azides, which were subjected to cycloaddition with phenylacetylene. A xylofuranose derivative having a free 5‐OH group was coupled with theobromine by Mitsunobu reaction and the obtained isonucleoside was functionalized at C‐1′ with a sulfonamide moiety, leading to a prospective nucleotide mimetic. Five compounds displayed selective inhibition of acetylcholinesterase in the micromolar concentration range, with an α‐glycosyl triazole (Ki = 3.53 µm) and its 1‐azido‐uronamide precursor (Ki = 1.73 µm) being the most active. Docking studies were performed to give insights into the different inhibitory behavior within glycosyl azide anomers. Two of the best inhibitors showed low toxicity in both a neural cell line and human fibroblasts, rendering them promising lead compounds and supporting further investigations.
The synthesis of glucuronamide‐based triazole nucleoside analogues and theobromine xylosyl 5′‐isonucleosides is reported. Key synthetic steps include alkyne–azide cycloaddition, MW‐assisted anomeric azidation, Mitsunobu reaction and N‐glycosylation. Some of these novel molecules display potent and selective inhibition of acetylcholinesterase and low toxicity in both neuronal cells and human fibroblasts.
The relationship between breastfeeding and the loss of weight gained during pregnancy remains unclear. This study aimed to investigate the association between breastfeeding and maternal weight ...changes during 24 months post‐partum. We studied a dynamic cohort comprising 315 women living in two cities in the state of Bahia, Brazil. The outcome variable was change in the post‐partum weight; the exposure variable was the duration and intensity of breastfeeding. Demographic, socio‐economic, environmental, reproductive and lifestyle factors were integrated in the analysis as covariates. The data were analysed using multiple linear regression and linear mixed‐effects models. The average cumulative weight loss at 6 months post‐partum was 2.561 kg (SD 4.585), increasing at 12 months (3.066 kg; SD 5.098) and decreasing at 18 months (1.993 kg; SD 5.340), being 1.353 kg (SD, 5.574) at 24 months post‐partum. After adjustment, the data indicated that for every 1‐point increase in breastfeeding score, the estimated average post‐partum weight loss observed was 0.191 kg at 6 months (P = 0.03), 0.090 kg at 12 months (P = 0.043), 0.123 kg at 18 months (P < 0.001) and 0.077 kg at 24 months (P = 0.001). Based on these results, we concluded that despite the low expressiveness, the intensity and duration of breastfeeding was associated with post‐partum weight loss at all stages of the study during the 24‐month follow‐up.
Eleven ruthenium-nucleoside conjugates with the general formula (η 5 -C 5 H 5 )Ru(PP)LPF 6 (PP = 1,2-bis(diphenylphosphino)ethane (Dppe), 2PPh 3 , and L = 3- N -( p -cyanobenzyl)thymidine derivative ...ligand) are reported. Both (η 5 -C 5 H 5 )Ru(Dppe)NC-R + and (η 5 -C 5 H 5 )Ru(PPh 3 ) 2 NC-R + scaffolds exhibit remarkable stability towards hydrolysis. Compounds show high cytotoxicity in HCT116 colon cancer cells, with IC 50 values down to 1.0 μM. Uptake competition experiments with 2′-deoxyadenosine revealed its cellular absorption to be independent of nucleoside transporters.
Several lanthanide and actinide tetranitrate ions, M(III)(NO3)4(-), were produced by electrospray ionization and subjected to collision induced dissociation in quadrupole ion trap mass spectrometers. ...The nature of the MO(NO3)3(-) products that result from NO2 elimination was evaluated by measuring the relative hydrolysis rates under thermalized conditions. Based on the experimental results it is inferred that the hydrolysis rates relate to the intrinsic stability of the M(IV) oxidation states, which correlate with both the solution IV/III reduction potentials and the fourth ionization energies. Density functional theory computations of the energetics of hydrolysis and atoms-in-molecules bonding analysis of representative oxide and hydroxide nitrates substantiate the interpretations. The results allow differentiation between those MO(NO3)3(-) that comprise an O(2-) ligand with oxidation to M(IV) and those that comprise a radical O(-) ligand with retention of the M(III) oxidation state. In the particular cases of MO(NO3)3(-) for M = Pr, Nd and Tb it is proposed that the oxidation states are intermediate between M(III) and M(IV).
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