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1.
Diagnostics (Basel) ; 14(5)2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38473029

RESUMEN

The Erythrocyte Sedimentation Rate (ESR) is a diagnostic estimator of systemic inflammation as a reflection of acute phase proteins circulating in the blood. The purpose of this manuscript is to evaluate the blood stability at room temperature (RT) and at 4 °C to avoid ESR diagnostic errors, as well as the accuracy of the VES-MATIC 5 analyzer. The ESR stability evaluation at RT for 24 h (4 h "T1", 6 h "T2", 8 h "T3", 10 h "T4", 24 h "T5") and at 4 °C (24 h, 36 h, 48 h) was carried out using 635 total samples, starting with T0 (2 h of venipuncture). For method comparison, 164 patients were analyzed using VES-MATIC 5 and then the Westergren reference method. The sample at RT is established by a significant gradual decrease in correlation R = 0.99 (T0 vs. T1), R = 0.97 (T0 vs. T2), R = 0.92 (T0 vs. T3), R = 0.87 (T0 vs. T4), and R = 0.40 (T0 vs. T5). The stability at 4 °C after 24 h, 36 h, and 48 h showed a regression of R = 0.99, R = 0.97, and R = 0.95, respectively. Therefore, ESR measurements on RT samples beyond 6 h after collection cannot be carried out, but the ESR can be measured until 36 h for samples stored at 4 °C. Moreover, the VES-MATIC 5 accuracy performance compared to the Westergren method (R = 0.96) is confirmed.

2.
Sci Total Environ ; 912: 169350, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38103606

RESUMEN

The prevention and control of biological patinas on outdoor stone monuments represent a demanding challenge for the conservation of cultural heritage also due to some microorganisms, particularly resistant to treatments, such as black meristematic fungi, an eco-physiological group well known for its tolerance to extreme conditions. Even if several methods and eco-friendly products have been proposed as new alternatives, traditional biocides are still far from being completely replaced. Recolonization is a natural process that occurs sooner or later after cleaning. The time that elapses until its occurrence can vary considerably depending on environmental conditions and the used products; unfortunately, the papers describing the effect of treatments over time are rare. This work aims to shed light on the recolonization process of marble surfaces in the ancient monumental cemetery of Bonaria (Cagliari) after nine years from treatments, evaluating the long-term efficiency of two different cleaning methods, namely dimethyl sulfoxide-based gel (DMSO-based gel) and Biotin T (a didecyldimethylammonium chloride-based product-). In this context, the microflora present before treatments and in the following years was assessed by culture-based methods and identified by molecular techniques, with attention on black meristematic fungi, which were used as reference for the most resistant lithobiontic organisms. Different environmental parameters, such as temperature, exposition, dominant winds, and rainfall, were considered, and infrared thermography, portable light microscopy, and image analysis were used. This research evidenced the influence of water availability and lightning in recolonization processes, the transition from the pioneer fungal community versus more resistant black fungal species after Biotin T treatment, and the long-lasting efficiency of the DMSO-based gel. These findings prove that this low-impact method deserves more attention in the conservation of outdoor marble monuments, emphasizing the importance of long-term studies.


Asunto(s)
Biotina , Carbonato de Calcio , Estudios de Seguimiento , Dimetilsulfóxido , Hongos
3.
Molecules ; 28(15)2023 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-37570738

RESUMEN

Ammonium N-(pyridin-2-ylmethyl)oxamate (AmPicOxam), synthesized from O-methyl-N-(pyridin-2-ylmethyl)oxamate, was spectroscopically and structurally characterized and assayed as a novel precursor for the protection and consolidation of carbonate stone substrates. An in-depth characterization of treated and untreated biomicritic limestone and white Carrara marble samples was carried out by means of SEM microscopy, X-ray powder diffraction, helium pycnometry, determination of water transport properties, and pull-off tests. The improved solubility (1.00 M, 16.5% w/w) of the title compound with respect to ammonium oxalate (0.4 M, 5% w/w) results in the formation of a thicker protective coating of calcium oxalate (CaOx) dihydrate (weddellite) on marble and biomicrite samples after the treatment with 5% and 12% w/w water solutions, producing a reduction in the stone porosity and increased cohesion. Theoretical calculations were carried out at the DFT level to investigate both the electronic structure of the N-(pyridin-2-ylmethyl)oxamate anion and the hydrolysis reaction leading from AmPicOxam to CaOx.

4.
J Environ Manage ; 321: 115984, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36001913

RESUMEN

Although the bioaccumulation of arsenic (As) in rice grains is a global health issue, its speciation is not less worrying. Despite the ascertained effectiveness of the intermittent irrigation methods in minimizing the amount of total As in rice, knowledge of its influence on the As speciation has been insufficient so far. Hence, this contribution was aimed to measure the concentrations of As(III), As(V), dimethylarsinic acid (DMA), and monomethylarsonic acid (MMA) in grains from twenty-six different rice genotypes irrigated either with continuous flooding (CF), periodic saturation (SA) or sprinkler irrigation (SP). In CF-irrigated rice, As(III) and DMA prevailed in roughly equal amounts, only As(III) was found in SA-irrigated rice, whereas As(V) was largely predominant on As(III) in SP-irrigated rice. Organoarsenic species were below the limits of detection (LoD) in rice irrigated by intermittent methods. Principal component analysis (PCA) explained the influence of the irrigation method on the total amount of As, its chemical species, and their correlation. Furthermore, PCA showed also significant differences in As speciation as a function of the rice genotype, whereas no differences were found among Indica and Japonica subspecies.


Asunto(s)
Arsénico , Oryza , Arsénico/análisis , Grano Comestible
5.
J Environ Manage ; 302(Pt B): 114105, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34801866

RESUMEN

Food is the major route of arsenic (As) intake for humans, and rice is the staple food for more than half of the world's population. Unfortunately, rice bioaccumulates large amounts of As from the paddy field, and the toxicity of this element in the kernel is closely linked to its chemical form. Therefore, it is of the utmost importance to have access to an integrated set of analytical methods, capable of measuring the concentration of As in its various chemical forms in soil and rice. Hence, the principal aim of this study was to assess and validate a group of inductively coupled plasma - mass spectrometry (ICP-MS) and IC-ICP-MS (IC, Ionic Chromatography) methods designed to measure the amount of the total or extracted As and its main chemical species (As(III), As(V), monomethylarsonic acid, MMA, and dimethylarsinic acid, DMA) in flours of rice grain and in soils. Great attention has been given to the assessment and the optimization of extraction methods of As species from these matrices. No appreciable interconversion among As species has been observed using an aqueous solution 1 mol dm-3 of phosphoric acid and 0.5 mol dm-3 of L (+)-ascorbic acid for the extraction from soils, and an aqueous solution 0.2% (w/v) of nitric acid for the extraction from rice flour. Validation has been successfully accomplished in terms of limit of detection, limit of quantification, linearity and accuracy. In addition to many certified reference materials, these methods have been tested on real samples of soils and rice grains of the Aleramo genotype obtained through traditional or intermittent irrigation methods. Data obtained revealed the critical role of the intermittent irrigation methods in determining the nature and the amount of the As chemical species in rice grains as well as in soils. As(V) is the only species found in soil irrigated by sprinkling, while the most toxic As(III) dominates in soil irrigated by continuous flooding. On the other hand, the most abundant species found in continuously flooded Aleramo rice grains are As(III) and - mostly - DMA, whereas As(V), less toxic than As(III), represents 60% of the total inorganic compounds measured in sprinkler-irrigated rice. Lastly, the total amount of As measured in this rice is 3.8% of that measured in rice irrigated by continuous flooding.


Asunto(s)
Arsénico , Oryza , Contaminantes del Suelo , Arsénico/análisis , Cromatografía Líquida de Alta Presión , Grano Comestible , Humanos , Suelo , Contaminantes del Suelo/análisis
6.
Molecules ; 26(21)2021 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-34771088

RESUMEN

The lack of interest in the determination of toxic elements in liquids for electronic cigarettes (e-liquids) has so far been reflected in the scarce number of accurate and validated analytical methods devoted to this aim. Since the strong matrix effects observed for e-liquids constitute an exciting analytical challenge, the main goal of this study was to develop and validate an ICP-MS method aimed to quantify 23 elements in 37 e-liquids of different flavors. Great attention has been paid to the critical phases of sample pre-treatment, as well as to the optimization of the ICP-MS conditions for each element and of the quantification. All samples exhibited a very low amount of the elements under investigation. Indeed, the sum of their average concentration was of ca. 0.6 mg kg-1. Toxic elements were always below a few tens of a µg per kg-1 and, very often, their amount was below the relevant quantification limits. Tobacco and tonic flavors showed the highest and the lowest concentration of elements, respectively. The most abundant elements came frequently from propylene glycol and vegetal glycerin, as confirmed by PCA. A proper choice of these substances could further decrease the elemental concentration in e-liquids, which are probably barely involved as potential sources of toxic elements inhaled by vapers.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Evaluación del Impacto en la Salud/métodos , Espectrometría de Masas/métodos , Sistemas Electrónicos de Liberación de Nicotina/normas , Evaluación del Impacto en la Salud/normas , Espectrometría de Masas/normas , Presión , Control de Calidad , Reproducibilidad de los Resultados , Temperatura
9.
J Appl Biomater Funct Mater ; 16(3): 186-202, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29996741

RESUMEN

This review presents "a state of the art" report on sustainability in construction materials. The authors propose different solutions to make the concrete industry more environmentally friendly in order to reduce greenhouse gases emissions and consumption of non-renewable resources. Part 1-the present paper-focuses on the use of binders alternative to Portland cement, including sulfoaluminate cements, alkali-activated materials, and geopolymers. Part 2 will be dedicated to traditional Portland-free binders and waste management and recycling in mortar and concrete production.


Asunto(s)
Materiales de Construcción , Tecnología Química Verde , Administración de Residuos/métodos , Álcalis/química , Compuestos de Aluminio/química , Silicatos de Aluminio/química , Compuestos de Calcio/química , Arcilla , Corrosión , Compuestos de Azufre/química
10.
J Appl Biomater Funct Mater ; 16(4): 207-221, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29991308

RESUMEN

The paper represents the "state of the art" on sustainability in construction materials. In Part 1 of the paper, issues related to production, microstructures, chemical nature, engineering properties, and durability of mixtures based on binders alternative to Portland cement were presented. This second part of the paper concerns the use of traditional and innovative Portland-free lime-based mortars in the conservation of cultural heritage, and the recycling and management of wastes to reduce consumption of natural resources in the production of construction materials. The latter is one of the main concerns in terms of sustainability since nowadays more than 75% of wastes are disposed of in landfills.


Asunto(s)
Materiales de Construcción , Administración de Residuos/métodos , Compuestos de Calcio/química , Arcilla/química , Tecnología Química Verde/métodos , Óxidos/química , Reciclaje , Goma/química , Dióxido de Silicio/química
11.
J Colloid Interface Sci ; 448: 320-30, 2015 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-25746185

RESUMEN

The ammonium salts of oxamate (AmOxam) and monomethyloxalate (AmMeox), structurally related to ammonium oxalate (AmOx), were synthesized and characterized as protecting agents/filler for calcareous stone substrates. Both compounds featured an improved solubility in water and alcoholic-water mixtures with respect to AmOx. While AmOxam is stable in aqueous solution and reacts with calcite to afford the corresponding insoluble calcium oxamate (CaOxam), AmMeox spontaneously undergoes hydrolysis to give ammonium monohydrogen oxalate hemihydrate (AmBiox) and calcium oxalate (CaOx). Both compounds have been tested for the restoration of naturally weathered marble and biomicritic limestone. The formation of a superficial layer of CaOxam and CaOx was observed on stone samples treated with AmOxam and AmMeox, respectively, depending on the solvent mixture. A quantum-mechanical study was carried out at DFT level in order to investigate the nature of the interactions occurring between the lithic substrate (calcite) and the passivating agents, showing how the structural modifications on oxalic acid derivatives can be exploited to fine-tune their interaction with the calcite surface.

12.
J Hazard Mater ; 161(2-3): 862-70, 2009 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-18514398

RESUMEN

In this work microstructure, porosity and hydration degree of cement-based solidified/stabilized wasteforms were studied before assessing their leaching behaviour. 2-Chloroaniline was chosen as a model liquid organic pollutant and included into cement pastes, which were also modified with different admixtures for concrete: a superplasticizer based on acrylic-modified polymer, a synthetic rubber latex and a waterproofing agent. An organoclay, modified with an ammonium quaternary salt (benzyl-dimethyl-tallowammonium, BDMTA), was added to the pastes as pre-sorbent agent of the organic matter. All the samples were dried up to constant weight in order to stop the hydration process at different times during the first 28 days of curing, typically, after 1 day (1d), 7 days (7d) and 28 days. Then, the microstructure of the hardened cement-clay pastes was investigated by powder X-ray diffraction (XRD). The hydration degree and porosity were studied by thermal analysis (TG/DTA) and mercury intrusion porosimetry (MIP), respectively. For samples cured for 28 days a short-term leach test set by Italian regulation for industrial waste recycling (D.M. 5 February 1998) was performed. The best results showed a 5% release of the total initial amount of organic pollutant.


Asunto(s)
Silicatos de Aluminio , Materiales de Construcción , Polímeros/química , Compuestos de Amonio Cuaternario/química , Adsorción , Compuestos de Anilina/química , Carbonato de Calcio/química , Arcilla , Mercurio/toxicidad , Microscopía Electrónica de Rastreo , Compuestos Orgánicos , Permeabilidad , Porosidad , Factores de Tiempo , Agua/química , Difracción de Rayos X
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