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1.
Mar Pollut Bull ; 191: 114908, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37086548

RESUMEN

The use of disposable personal protective equipment (PPE) as a control measure to avoid transmission against COVID-19 has generated a challenge to the waste management and enhances plastic pollution in the environment. The research aims to monitor the presence of PPE waste and other plastic debris, in a time interval where the use of face mask at specific places was still mandatory, on the coastal areas of Granada (Spain) which belongs to the Mediterranean Sea. Four beaches called La Rijana, La Charca, La Rábita and Calahonda were examined during different periods. The total amount of sampled waste was 17,558 plastic units. The abundance, characteristics and distribution of PPE and other plastic debris were determined. Results showed that the observed amount of total plastic debris were between 2.531·10-2 and 24.487·10-2 units per square meter, and up to 0.136·10-2 for PPE debris, where face masks represented the 92.22 % of the total PPE debris, being these results comparable to previous studies in other coastal areas in the world. On the other hand, total plastic debris densities were in the range from 2.457·10-2 to 92.219·10-2 g/m2 and densities were up to 0.732·10-2 for PPE debris. PPE debris supposed 0.79 % of the weight of total waste and the 0.51 % of total items. Concerning non-PPE plastic waste: cigarettes filters, food containers and styrofoam were the most abundant items (42.95, 10.19 and 16.37 % of total items, respectively). During vacation periods, total plastic debris amount increased 92.19 % compared to non-vacation periods. Regarding type of beaches, the presence of plastic debris was significantly higher on touristic/recreational than in fishing beaches. Data showed no significant differences between accessible and no-accessible beaches, but between periods with restrictive policy about mask face use and periods with non-restrictive policy data suggest significant differences between densities (g/m2) for PPE litter. The amount of PPEs debris is also correlated with the number of cigarettes filters (Person's r = 0.650), food containers (r = 0.782) and other debris (r = 0.63). Finally, although interesting results were provided in this study, further research is required to better understand the consequences of this type of pollution and to provide viable solutions to this problem.


Asunto(s)
COVID-19 , Residuos , Humanos , Residuos/análisis , Monitoreo del Ambiente/métodos , España , Playas , COVID-19/prevención & control , Plásticos , Equipo de Protección Personal
2.
Waste Manag ; 161: 116-141, 2023 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-36878040

RESUMEN

In circular economy, useful plastic materials are kept in circulation as opposed to being landfilled, incinerated, or leaked into the natural environment. Pyrolysis is a chemical recycling technique useful for unrecyclable plastic wastes that produce gas, liquid (oil), and solid (char) products. Although the pyrolysis technique has been extensively studied and there are several installations applying it on the industrial scale, no commercial applications for the solid product have been found yet. In this scenario, the use of plastic-based char for the biogas upgrading may be a sustainable way to transform the solid product of pyrolysis into a particularly beneficial material. This paper reviews the preparation and main parameters of the processes affecting the final textural properties of the plastic-based activated carbons. Moreover, the application of those materials for the CO2 capture in the processes of biogas upgrading is largely discussed.


Asunto(s)
Dióxido de Carbono , Plásticos , Plásticos/química , Carbón Orgánico , Biocombustibles , Pirólisis
3.
Waste Manag ; 137: 179-189, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34794036

RESUMEN

The establishment of a method of separation of materials from Tetra Pak waste to obtain products for use as raw material, fuel or other purposes was investigated in this study. First, the feasibility of hydrothermal treatment for the production of a solid fuel (hydrochar) and solid fraction formed by polyethylene and aluminum, called composite was analyzed. The results indicated that hydrothermal treatment performed at 240 °C yield the formation of hydrochar with good properties for its use as fuel and a composite of polyethylene and aluminum. The best conversion and separation of the cardboard and polyethylene/aluminum were obtained using 120 min as operating time. Then, the recovery of the aluminum fraction from the composite by using spent olive oil waste was studied. A partial separation of the composite layers (polyethylene and aluminum) was accomplished with improved aluminum purity for higher operating temperatures. Finally, the operating conditions of the pyrolysis process for the production of a solid (char) and high purity composite (aluminum) were optimized. The characterization results indicated that both char and aluminum resulting from the pyrolysis of the Tetra Pak at 400 °C still have a significant amount of polyethylene while higher purity levels of aluminum can be obtained at temperatures equal of higher than 500 °C.


Asunto(s)
Plásticos , Pirólisis , Aluminio , Polietileno , Temperatura
4.
Indian J Dermatol Venereol Leprol ; 88(4): 464-477, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34672479

RESUMEN

Leprosy is a chronic disease with clinical presentations according to the immunologic spectrum. Lepromatous form is the most advanced, with the highest transmissibility and risk of causing disabilities. Lucio's phenomenon is a rare manifestation among lepromatous patients with a rapid and severe evolution and high mortality. It is difficult to differentiate from ulcerative/necrotic erythema nodosum leprosum and has no consensus on how it should be treated. This article is a qualitative review of the literature after the introduction of multidrug therapy, aiming to bring consensus related to the clinical, laboratory and histopathological diagnostic criteria of the disease and its management.


Asunto(s)
Eritema Nudoso , Lepra Lepromatosa , Lepra Multibacilar , Lepra , Quimioterapia Combinada , Eritema Nudoso/diagnóstico , Eritema Nudoso/terapia , Humanos , Leprostáticos/uso terapéutico , Lepra/diagnóstico , Lepra/tratamiento farmacológico , Lepra Lepromatosa/diagnóstico , Lepra Lepromatosa/tratamiento farmacológico , Lepra Lepromatosa/patología , Lepra Multibacilar/tratamiento farmacológico
5.
Mar Pollut Bull ; 170: 112677, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34186451

RESUMEN

The excessive use of plastic in our society is causing a massive accumulation, since it is a non-biodegradable product and with still poor recycling rates. This effect can be observed in the seas, which more and more plastic waste are accumulating. The present work is a critical review, based on all currently available literature, that reports environmental status of marine plastic pollution, especially microplastic pollution, in Spain. The three Spanish water areas with the highest presence of plastics are the Alboran Sea, the Gulf of Alicante and the vicinity of Barcelona probably related to fishing and industrial activities and high population densities. With regard to microplastic contamination on beaches in Spain, annual monitoring by the Spanish government shows contamination along the entire coast of the country, with particularly high concentrations in the Canary Islands (between 800 and 8800 particles/m2 in spring). Between 40 and 50% of the particles analyzed were pellets and the main factors postulated for the distribution of these particles are marine currents and the geomorphological characteristics. With regards to biota, ingestion of microplastics by fish has been intensely confirmed and, important differences were observed between the locations of the sampling, being bogues (Boops boops) one of the fish species more studied in Spain. Finally, the work includes a revision of European and Spanish legislation about plastics and marine pollution and some strategies to reduce this kind of contamination in Spain.


Asunto(s)
Plásticos , Contaminantes Químicos del Agua , Animales , Monitoreo del Ambiente , Contaminación Ambiental , Microplásticos , España , Residuos/análisis , Contaminantes Químicos del Agua/análisis
6.
Sci Total Environ ; 776: 145999, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33647658

RESUMEN

Sources contributing to specific concentration of microplastics and fibers are still not completely understood. This study aimed at assessing the concentrations of microplastics (2-5000 µm) and fibers (18-5667 µm) in three areas of distinct influences in the Douro river, Porto, Portugal: (i) a countryside area; (ii) a wastewater treatment effluent release zone; and (iii) an area in proximity to a boat dock and maintenance station. Nile Red staining coupled with microscopy allowed the identification of small microplastics (≥2 µm) with a median concentration of the three areas of 231 MP L-1. Most were fragments (69%). Sizes <40 µm were the most abundant (84%). Highest concentrations of microplastics were found near the boat dock/maintenance and lowest in the countryside area. Fibers were mostly natural (non-synthetic, 63%). Highest concentrations of fibers were found in the area influenced by the wastewater effluent, especially of synthetic fibers, and lowest in the countryside area. Concentration of all fibers and synthetic fibers was 46 F L-1 and 6 F L-1, respectively. High concentrations of microplastics and fiber contamination suggest that the wastewater treatment plant effluent and boat dock/maintenance are the likely sources originating hotspot areas.

7.
Foods ; 9(11)2020 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-33182839

RESUMEN

In this work, liquid hot water pretreatment (autohydrolysis) was used to improve enzymatic hydrolysis of a commonly consumed vegetable waste in Spain, Italian green pepper, to finally produce fermentable sugars. Firstly, the effect of temperature and contact time on sugar recovery during pretreatment (in insoluble solid and liquid fraction) was studied in detail. Then, enzymatic hydrolysis using commercial cellulase was performed with the insoluble solid resulting from pretreatment. The objective was to compare results with and without pretreatment. The results showed that the pretreatment step was effective to facilitate the sugars release in enzymatic hydrolysis, increasing the global sugar yield. This was especially notable when pretreatment was carried out at 180 °C for 40 min for glucose yields. In these conditions a global glucose yield of 61.02% was obtained. In addition, very low concentrations of phenolic compounds (ranging from 69.12 to 82.24 mg/L) were found in the liquid fraction from enzymatic hydrolysis, decreasing the possibility of fermentation inhibition produced by these components. Results showed that Italian green pepper is an interesting feedstock to obtain free sugars and prevent the enormous quantity of this food waste discarded annually.

8.
Clin Transl Oncol ; 22(12): 2364-2368, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32449128

RESUMEN

BACKGROUND: There are no large reported series determining the Covid-19 cancer patient's characteristics. We determine whether differences exist in cumulative incidence and mortality of Covid-19 infection between cancer patients and general population in Madrid. MATERIAL AND METHODS: We reviewed 1069 medical records of all cancer patients admitted at Oncology department between Feb 1 and April 7, 2020. We described Covid-19 cumulative incidence, treatment outcome, mortality, and associated risk factors. RESULTS: We detected 45/1069 Covid-19 diagnoses in cancer patients vs 42,450/6,662,000 in total population (p < 0.00001). Mortality rate: 19/45 cancer patients vs 5586/42,450 (p = 0.0001). Mortality was associated with older median age, adjusted by staging and histology (74 vs 63.5 years old, OR 1.06, p = 0.03). Patients who combined hydroxychloroquine and azithromycin presented 3/18 deaths, regardless of age, staging, histology, cancer treatment and comorbidities (OR 0.02, p = 0.03). CONCLUSION: Cancer patients are vulnerable to Covid-19 with an increase in complications. Combined hydroxychloroquine and azithromycin is presented as a good treatment option.


Asunto(s)
Infecciones por Coronavirus/complicaciones , Infecciones por Coronavirus/mortalidad , Neoplasias/complicaciones , Neoplasias/epidemiología , Neumonía Viral/complicaciones , Neumonía Viral/mortalidad , Anciano , Azitromicina/uso terapéutico , Betacoronavirus/aislamiento & purificación , COVID-19 , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/tratamiento farmacológico , Combinación de Medicamentos , Femenino , Humanos , Hidroxicloroquina/uso terapéutico , Incidencia , Masculino , Persona de Mediana Edad , Neoplasias/patología , Pandemias , Neumonía Viral/diagnóstico , Neumonía Viral/tratamiento farmacológico , Factores de Riesgo , SARS-CoV-2 , España/epidemiología , Resultado del Tratamiento
10.
Environ Pollut ; 255(Pt 3): 113363, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31614247

RESUMEN

Microplastics can adsorb chemical pollutants such as metals or pharmaceuticals, and transferred them along the food chain. In this work, an investigation of the adsorption of Cd, Co, Cr, Cu, Ni, Pb and Zn by five different types of microplastics was performed in Milli-Q water and natural waters (seawater, urban wastewater and irrigation water) via a series of batch adsorption experiments. The effects of concentration of metals and physicochemical characteristics of polymers were particularly studied. Results revealed a significant adsorption of lead, chromium and zinc on microplastics, especially on polyethylene and polyvinyl chloride. In the case of polyethylene terephthalate, it showed little adsorption capacity. Specific surface, porosity and morphology are characteristics that affect the molecular interactions. The adsorption isotherms were better described by Langmuir model, which indicates that the main adsorption mechanism might be chemical adsorption. Finally, results obtained in natural waters indicated that dissolved organic matter may play a major role on metal adsorption on microplastics. Results showed an enhancement of metal adsorption in waters with high chemical and biological oxygen demands as urban wastewater and irrigation water.


Asunto(s)
Metales Pesados/química , Microplásticos/química , Contaminantes Químicos del Agua/química , Adsorción , Cromo , Contaminantes Ambientales , Metales Pesados/análisis , Compuestos Orgánicos , Plásticos , Agua de Mar/química , Aguas Residuales , Agua/química , Contaminantes Químicos del Agua/análisis , Zinc
11.
Hypertension ; 74(4): 826-832, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31476911

RESUMEN

We aimed to estimate the effects of a lifelong exposure to high systolic blood pressure (SBP) on left ventricular (LV) structure and function using Mendelian randomization. A total of 5596 participants of the UK Biobank were included for whom cardiovascular magnetic resonance imaging and genetic data were available. Major exclusion criteria included nonwhite ethnicity, major cardiovascular disease, and body mass index >30 or <18.5 kg/m2. A genetic risk score to estimate genetically predicted SBP (gSBP) was constructed based on 107 previously established genetic variants. Manual cardiovascular magnetic resonance imaging postprocessing analyses were performed in 300 individuals at the extremes of gSBP (150 highest and lowest). Multivariable linear regression analyses of imaging biomarkers were performed using gSBP as continuous independent variable. All analyses except myocardial strain were validated using previously derived imaging parameters in 2530 subjects. The mean (SD) age of the study population was 62 (7) years, and 52% of subjects were female. Corrected for age, sex, and body surface area, each 10 mm Hg increase in gSBP was significantly (P<0.0056) associated with 4.01 g (SE, 1.28; P=0.002) increase in LV mass and with 2.80% (SE, 0.97; P=0.004) increase in LV global radial strain. In the validation cohort, after correction for age, sex, and body surface area, each 10 mm Hg increase in gSBP was associated with 5.27 g (SE, 1.50; P<0.001) increase in LV mass. Our study provides a novel line of evidence for a causal relationship between SBP and increased LV mass and with increased LV global radial strain.


Asunto(s)
Presión Sanguínea/fisiología , Corazón/fisiopatología , Hipertensión/fisiopatología , Hipertrofia Ventricular Izquierda/fisiopatología , Función Ventricular Izquierda/fisiología , Anciano , Índice de Masa Corporal , Femenino , Corazón/diagnóstico por imagen , Humanos , Hipertensión/diagnóstico por imagen , Hipertrofia Ventricular Izquierda/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Masculino , Análisis de la Aleatorización Mendeliana , Persona de Mediana Edad
12.
Arq. bras. med. vet. zootec. (Online) ; 71(2): 715-719, mar.-abr. 2019. tab
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1038591

RESUMEN

O objetivo deste trabalho foi identificar polimorfismos genéticos de leptina, ß-lactoglobulina e fator de transcrição pituitária (PIT1) e avaliar seus efeitos na composição química e na contagem de células somáticas de leite de vacas leiteiras mestiças que vivem em um clima quente. Um total de 291 vacas leiteiras mestiças foram investigadas. Foram coletadas amostras de sangue para extração de DNA e amostras de leite. As amostras foram classificadas em três grupos genéticos: 12/ (42), 34/ (83) e 78/ (166) Holandês x Guzerá. As frequências de alelos e genótipos foram determinadas e o equilíbrio Hardy-Weinberg foi avaliado. Foram realizadas análises da composição do leite (gordura, proteína, lactose e extracto seco desengordurado), contagem de células somáticas e rendimento leiteiro. Os grupos genéticos e os polimorfismos genéticos para cada gene foram utilizados como efeitos fixos na análise. O único polimorfismo encontrado em equilíbrio de Hardy-Weinberg foi para o genótipo da ß-lactoglobulina. No presente estudo, era esperado que a maioria das variáveis de composição variasse entre os genótipos. Já se sabe que os cruzamentos dão origem a animais com características fenotípicas e genotípicas. No entanto, os polimorfismos não influenciaram a composição e a qualidade do leite nas vacas 12/ , 34/ e 78/ Holstein x Guzerá mantidas em um clima quente.(AU)


Asunto(s)
Animales , Femenino , Embarazo , Bovinos , Leche/citología , Leche/química , Leptina/genética , Lactoglobulinas/genética
13.
Mar Pollut Bull ; 139: 91-99, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30686453

RESUMEN

Plastic pollution in oceans is a global problem, with growing research efforts focusing on the threat of microplastics (<5 mm fractions). A source of microplastics pollution is derived from personal care products that contain polyethylene micro-spheres which are not captured by wastewater plants. In this work, ten personal care products (mainly scrubs) containing microplastics and marketed in Spain, were physico-chemically characterized. The obtained results proved that those microplastics had different particle size and are presented in high percentages in some cases, between 6 and 7% of the total product. Products with smaller particles usually showed higher concentrations than products with larger particles. Although all the microplastics were shown to be polyethylene, some impurities were observed that demonstrated the presence of silicates and oxides in the microplastics. Regards to morphology, the shape of the particles was irregular in general, although some completely spherical particles can be observed.


Asunto(s)
Cosméticos/química , Monitoreo del Ambiente/métodos , Polietileno/química , Contaminantes Químicos del Agua/química , Cosméticos/análisis , Tamaño de la Partícula , Polietileno/análisis , España , Propiedades de Superficie , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis
14.
Bioresour Technol ; 268: 169-175, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30077173

RESUMEN

The present study aims to solve two major challenges of the current society. On the one hand, it investigated the heavy metal removal from mining wastewater. On the other hand, it proposed an alternative use for olive cake. Firstly, a physic-chemical characterization of real wastewater and hydrolyzed olive cake was carried out. Secondly, a study of the affinity of the material for the different metals (chromium, manganese, copper, zinc, nickel and lead) was performed. The hydrolyzed olive cake showed a low content in ash (3.08%) and in water-soluble compounds (2.80%). The material presented the highest retention capacity for the lead (41.54 mg/g) and the lowest for the manganese (3.57 mg/g). After that, biosorption experiments in fixed-bed column were carried out using mining real water. In order to improve the biosorption capacity, the water pH was raised up to 6. The results were quite satisfactory with respect to others similar studies.


Asunto(s)
Metales Pesados/aislamiento & purificación , Olea , Purificación del Agua , Adsorción , Biomasa , Concentración de Iones de Hidrógeno , Minería , Níquel , Aguas Residuales , Contaminantes Químicos del Agua
15.
Bioresour Technol ; 261: 104-116, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29654995

RESUMEN

This research aims to provide a better knowledge of the thermal decomposition of the olive cake as well as this lignocellulosic material loaded, in a previous stage of biosorption, with heavy metals for its use in processes of energy recovery. Firstly, isolation of constituents of the olive cake was carried out. Then, experiments were performed by thermogravimetric analysis (TGA) and differential thermogravimetry (DTG) under inert and oxidative atmosphere at a heating rate of 15 K/min for each isolated fraction. Next, adequate reactions schemes were proposed to find kinetic parameters. Validation of these schemes were verified by the goodness of fitting between experimental and simulated data. Also, some important combustion characteristics such as ignition and burnout temperatures were determined. With regard to the effect of metals, cadmium, copper, chromium, nickel and lead present in metal-loaded olive cake did not modify values of kinetic parameters which described the thermal decomposition processes.


Asunto(s)
Metales , Olea , Fraccionamiento Químico , Cinética , Termogravimetría
16.
Water Sci Technol ; 77(5-6): 1386-1396, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29528326

RESUMEN

After checking the success of the biosorption process to remove heavy metals from wastewater using olive tree pruning as a cheap biosorbent in the laboratory scale, the scale-up is necessary to progress towards industrial applications chance. The aim of this work was the study of the effect of scale-up in the process of biosorption of Pb(II) with olive tree pruning in a packed bed column. Experiments were performed using two different scale-up criteria and results obtained in both scales were compared. Similar parameters were obtained for each pair of equivalent tests, with a slightly advanced of the obtained breakthrough curves in the pilot plant. The experimental results were fitted by the Thomas model and the obtained mean values were KTh = 0.187 mL/min·mg and q0 = 20.59 mg/g for criterion 1 and KTh = 0.217 mL/min·mg and q0 = 20.27 mg/g for criterion 2. Finally, the mathematical model was applied to simulate industrial applications and it was obtained that under optimal operative conditions, a column according to the criterion 1 was able to operate 2.3 h, and a column according to the criterion 2 was able to operate for 3.6 h.


Asunto(s)
Modelos Teóricos , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/química , Adsorción , Metales Pesados , Olea , Contaminantes Químicos del Agua
17.
Bioresour Technol ; 252: 100-109, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29306712

RESUMEN

Continuous copper biosorption in fixed-bed column by olive stone and pinion shell was studied. The effect of three operational parameters was analyzed: feed flow rate (2-6 ml/min), inlet copper concentration (40-100 mg/L) and bed-height (4.4-13.4 cm). Artificial Neural-Fuzzy Inference System (ANFIS) was used in order to optimize the percentage of copper removal and the retention capacity in the column. The highest percentage of copper retained was achieved at 2 ml/min, 40 mg/L and 4.4 cm. However, the optimum biosorption capacity was obtained at 6 ml/min, 100 mg/L and 13.4 cm. Finally, breakthrough curves were simulated with mathematical traditional models and ANFIS model. The calculated results obtained with each model were compared with experimental data. The best results were given by ANFIS modelling that predicted copper biosorption with high accuracy. Breakthrough curves surfaces, which enable the visualization of the behavior of the system in different process conditions, were represented.


Asunto(s)
Cobre , Olea , Purificación del Agua , Agua , Adsorción , Concentración de Iones de Hidrógeno , Contaminantes Químicos del Agua
18.
Am J Dermatopathol ; 40(7): 491-497, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29293127

RESUMEN

A great number of lichenoid lesions have overlapping clinicopathological features, so the use of adjunct tests to establish definitive diagnosis is recommended for correct management and prognosis of the lesions. In this context, direct immunofluorescence (DIF) can be a useful tool. Thus, this study aimed to characterize the clinical, histopathological, and DIF pattern in patients with oral lichen planus (OLP) and patients with oral lichenoid lesions (OLLs). Patients with OLP and patients with OLL were characterized and compared with patients with mucous membrane pemphigoid, pemphigus vulgaris, and fibrous hyperplasia through a cross-sectional study. Patients with OLP (n = 30) and patients with OLL (n = 26) were mostly white women in the fifth decade of age, with reticular lesions mainly on the buccal mucosa. All patients with OLP and half of the patients with OLL showed liquefaction degeneration at the basal cell layer and a band-like lymphocytic infiltrate in the subepithelial tissue. Twenty-two patients with OLP (73.3%), 10 with OLL (38.4%), 25 with mucous membrane pemphigoid (96.1%), and all with pemphigus vulgaris (100%) had positive DIF. There was no positive DIF in patients with fibrous hyperplasia. The most frequent DIF pattern in patients with OLP and patients with OLL was linear fibrinogen at the basement membrane zone, and a logistic regression model for positive DIF found statistically significant difference in OLP versus OLL (odds ratio, 3.73; confidence interval, 1.23-11.38). Although clinical and histopathological features are sufficient for diagnosing most of the patients with OLP and OLL, DIF is a key tool in differentiating some lichenoid lesions and could improve the diagnosis of OLP and OLL, especially in lesions showing typical clinical and histological features of OLP.


Asunto(s)
Liquen Plano Oral/diagnóstico , Erupciones Liquenoides/diagnóstico , Enfermedades de la Boca/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Diagnóstico Diferencial , Femenino , Técnica del Anticuerpo Fluorescente Directa , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
19.
Sci Total Environ ; 613-614: 418-427, 2018 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-28918273

RESUMEN

Heavy metal-loaded almond shell was subjected to pyrolysis to understand the effect of the presence of different heavy metals on its thermal degradation. Pyrolysis behavior of native and metal-loaded samples was studied by thermogravimetric analysis. Similar shapes of thermogravimetric curves indicate that the presence of cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni) and lead (Pb) did not change the main degradation pathways of almond shell. However, the temperature at which the decomposition in each stage takes place at a higher rate and char yield was considerably modified by the presence of Cr and Ni. Then, pyrolysis tests of the almond shell samples were performed in a moving tubular reactor at 700°C. Gases and volatile organic compounds were collected using Tedlar bags and semivolatile organic compounds were collected using a resin as adsorbent. Significant changes were obtained in the composition of the gaseous fraction as a result of the metal impregnation. The main changes in the composition of the gas were observed for Ni-loaded sample, which presented the highest H2 and CO yields. Also, the yields of most of the light hydrocarbons decrease in the presence of metal, while the rest remain quite similar. The total PAH yields reached 103µg/g for nickel-loaded sample (NiAS), 164µg/g for copper-loaded sample (CuAS), 172µg/g for lead-loaded sample (PbAS), 245µg/g for native sample (AS), 248µg/g for cadmium-loaded sample (CdAS) and 283µg/g for chromium-loaded sample (CrAS). Nickel is the most effective in the higher aromatic tar reduction, followed by Cu and Pb, whereas the presence of Cd does not affect the total emissions of PAHs. Finally, the carcinogenic potency of the samples was calculated. Native sample and the sample loaded with Cr presented slightly higher values associated to the presence of small amounts of benzo(a)pyrene.

20.
Bioresour Technol ; 249: 557-566, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29091838

RESUMEN

This paper presents a kinetic analysis of thermal decomposition of olive tree pruning from its basic compounds in pyrolysis and combustion reactions. Experiments were performed by TGA under inert and oxidant conditions and results indicated that the decomposition of the olive tree pruning was related to the material composition. Pseudo-mechanistic models were proposed estimating the yield of pyrolysis on its basic compounds (hemicelluloses, cellulose and lignin). Validity and reliability of the proposed kinetic models were verified by the good fitting between the simulated and experimental curves (with values of R2 higher than 0.99 in most cases). Moreover, during the fractionation process, an acid fraction was obtained with great fuel properties, a high calorific value and a low residue after its combustion.


Asunto(s)
Olea , Fraccionamiento Químico , Cinética , Reproducibilidad de los Resultados , Termogravimetría
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