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1.
Angew Chem Int Ed Engl ; 62(36): e202301909, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37162030

RESUMEN

Photocatalytic biomass conversion into high-value chemicals and fuels is considered one of the hottest ongoing research and industrial topics toward sustainable development. In short, this process can cleave Cß -O/Cα -Cß bonds in lignin to aromatic platform chemicals, and further conversion of the polysaccharides to other platform chemicals and H2 . From the chemistry point of view, the optimization of the unique cooperative interplay of radical oxidation species (which are activated via molecular oxygen species, ROSs) and substrate-derived radical intermediates by appropriate control of their type and/or yield is key to the selective production of desired products. Technically, several challenges have been raised that face successful real-world applications. This review aims to discuss the recently reported mechanistic pathways toward selective biomass conversion through the optimization of ROSs behavior and materials/system design. On top of that, through a SWOT analysis, we critically discussed this technology from both chemistry and technological viewpoints to help the scientists and engineers bridge the gap between lab-scale and large-scale production.

2.
Artículo en Inglés | MEDLINE | ID: mdl-37107783

RESUMEN

Enhanced recovery after surgery (ERAS) and prehabilitation programs are multidisciplinary care pathways to reduce stress response and improve perioperative outcomes, which also include nutritional interventions. The aim of this study is to assess the impact of protein supplementation with 20 mg per day before surgery in a prehabilitation program in postoperative serum albumin, prealbumin, and total proteins in endometrial cancer patients undergoing laparoscopic surgery. METHODS: A prospective study including patients who underwent laparoscopy for endometrial cancer was conducted. Three groups were identified according to ERAS and prehabilitation implementation (preERAS, ERAS, and Prehab). The primary outcome was levels of serum albumin, prealbumin, and total protein 24-48 h after surgery. RESULTS: A total of 185 patients were included: 57 in the preERAS group, 60 in the ERAS group, and 68 in the Prehab group. There were no basal differences in serum albumin, prealbumin, or total protein between the three groups. After surgery, regardless of the nutritional intervention, the decrease in the values was also similar. Moreover, values in the Prehab group just before surgery were lower than the initial ones, despite the protein supplementation. CONCLUSIONS: Supplementation with 20 mg of protein per day does not impact serum protein levels in a prehabilitation program. Supplementations with higher quantities should be studied.


Asunto(s)
Neoplasias Endometriales , Ejercicio Preoperatorio , Humanos , Femenino , Prealbúmina , Estudios Prospectivos , Neoplasias Endometriales/cirugía , Suplementos Dietéticos
3.
Bioresour Technol ; 369: 128470, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36509304

RESUMEN

Microwave-assisted deep eutectic solvent (DES) has received attention as an ultrafast pretreatment method in lignocellulose fractionation. This study investigated the improvement of milled softwood mixture (MSM) fractionation with chlorine chloride-formic acid (ChCl:FA) to obtain residues with high glucan retention and purity while removing majority of the lignin and hemicelluloses. At the optimum pretreatment conditions i.e., ChCl:FA (1:4), 140 °C, 14 min, 800 W and 15 % (w/v), 96.2 % hemicellulose removal, 90.1 % delignification and 93.5 % glucan retention were achieved. About 85 % lignin was recovered with a 95 % purity when solid loading was 10-20 % (w/v). This study showed that microwave assisted ChCl:FA pretreatment was a suitable means to fractionate MSM to achieve high quality glucan and lignin at high solid loading.


Asunto(s)
Disolventes Eutécticos Profundos , Lignina , Lignina/química , Microondas , Biomasa , Solventes/química , Cloruros , Hidrólisis
4.
Chem Mater ; 34(19): 8760-8768, 2022 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-36444288

RESUMEN

A key step in creating efficient and long-lasting catalysts is understanding their deactivation mechanism(s). On this basis, the behavior of a series of Pd/corundum materials during several hydrogen adsorption/desorption cycles was studied using temperature-programmed desorption coupled with mass spectrometry and aberration-corrected transmission electron microscopy. The materials, prepared by impregnation and by sputtering, presented uniform well-dispersed Pd nanoparticles. In addition, single atoms and small clusters of Pd were only detected in the materials prepared by impregnation. Upon exposure to hydrogen, the Pd nanoparticles smaller than 2 nm and the single atoms did not present any change, while the larger ones presented a core-shell morphology, where the core was Pd and the shell was PdH x . The results suggest that the long-term activity of the materials prepared by impregnation can be attributed solely to the presence of small clusters and single atoms of Pd.

5.
Artículo en Inglés | MEDLINE | ID: mdl-36141915

RESUMEN

This systematic review aimed to examine the health outcomes and environmental impact of edible insect consumption. Following PRISMA-P guidelines, PubMed, Medline ProQuest, and Cochrane Library databases were searched until February 2021. Twenty-five articles met inclusion criteria: twelve animal and six human studies (randomized, non-randomized, and crossover control trials), and seven studies on sustainability outcomes. In animal studies, a supplement (in powdered form) of 0.5 g/kg of glycosaminoglycans significantly reduced abdominal and epididymal fat weight (5-40% and 5-24%, respectively), blood glucose (10-22%), and total cholesterol levels (9-10%), and a supplement of 5 mg/kg chitin/chitosan reduced body weight (1-4%) and abdominal fat accumulation (4%) versus control diets. In other animal studies, doses up to 7-15% of edible insect inclusion level significantly improved the live weight (9-33%), reduced levels of triglycerides (44%), cholesterol (14%), and blood glucose (8%), and increased microbiota diversity (2%) versus control diet. In human studies, doses up to 7% of edible insect inclusion level produced a significant improvement in gut health (6%) and reduction in systemic inflammation (2%) versus control diets and a significant increase in blood concentrations of essential and branched-chain amino acids and slowing of digestion (40%) versus whey treatment. Environmental indicators (land use, water footprint, and greenhouse gas emissions) were 40-60% lower for the feed and food of edible insects than for traditional animal livestock. More research is warranted on the edible insect dose responsible for health effects and on environmental indicators of edible insects for human nutrition. This research demonstrates how edible insects can be an alternative protein source not only to improve human and animal nutrition but also to exert positive effects on planetary health.


Asunto(s)
Quitosano , Insectos Comestibles , Gases de Efecto Invernadero , Animales , Humanos , Aminoácidos de Cadena Ramificada , Glucemia , Glicosaminoglicanos , Triglicéridos
6.
Artículo en Inglés | MEDLINE | ID: mdl-35329311

RESUMEN

This qualitative ethnographic study identifies how problems in the feeding process of a group of people with functional diversity influence different eating situations. The study, which was carried out in the Autonomous Community of Castilla La Mancha, Spain, is based on interviews conducted at the headquarters of the different participating associations for functionally diverse people, at the participants' homes, and in public spaces. The study included 27 subjects aged between 18-75 years. Their functional diversity had caused significant changes in their sociability, particularly in contexts associated with food consumption. The analysis identified three main themes: social ghettoisation and culinary loneliness; stigma, shame, feeling like a burden, and loneliness; and exclusion or self-exclusion at the dining table. Our participants' narratives underscored the importance of acknowledging the significance of changes in eating-related sociability due to functional diversity. For the study subjects, grief, loneliness, and shame contributed to disassociating food consumption from social celebrations, withdrawing from restaurant meals, or conversations while eating to avoid other people's stares.


Asunto(s)
Soledad , Comidas , Adolescente , Adulto , Anciano , Dieta , Humanos , Persona de Mediana Edad , Investigación Cualitativa , España , Adulto Joven
7.
Molecules ; 26(20)2021 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-34684814

RESUMEN

Currently, there is great interest in the use of TiO2 for photocatalytic remediation of wastewater. Doping, heterojunction, and immobilization on porous materials are effective methods to improve the photocatalytic efficiency of this semiconductor oxide. In this study, ZnTiO3/TiO2 (ZTO) and ZnTiO3/TiO2/La (ZTO/La) nanocomposites were successfully prepared and immobilized on diatomaceous earth (DE). The composition and texture of the composites prepared were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), diffuse reflectance spectroscopy (DRS), scanning electron microscopy (SEM-EDX), and specific surface area (SSA). The adsorption capacity and photocatalytic activity of the composites were determined via degradation of methylene blue (MB) in batch reactors. The materials evaluated were prepared in the shape of 0.2 cm (diameter) and 1.0 cm (length) cylindrical extrudates. The results indicate that the ZTO/La-DE composite exhibited higher efficiency for the removal of MB under solar irradiation than both ZTO-DE and DE. The pseudo-second-order model and the Langmuir isotherm model were better suited to explain the adsorption process. The highest degradation percentage of MB obtained was 96% after 150 min of irradiation. The results indicate that synthesized composite could be used for the removal of cationic dyes in wastewater.

8.
Molecules ; 26(13)2021 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-34206305

RESUMEN

The search for alternative materials with high dye adsorption capacity, such as methylene blue (MB), remains the focus of current studies. This computational study focuses on oxides ZnTiO3 and TiO2 (anatase phase) and on their adsorptive properties. Computational calculations based on DFT methods were performed using the Viena Ab initio Simulation Package (VASP) code to study the electronic properties of these oxides. The bandgap energy values calculated by the Hubbard U (GGA + U) method for ZnTiO3 and TiO2 were 3.17 and 3.21 eV, respectively, which are consistent with the experimental data. The most favorable orientation of the MB adsorbed on the surface (101) of both oxides is semi-perpendicular. Stronger adsorption was observed on the ZnTiO3 surface (-282.05 kJ/mol) than on TiO2 (-10.95 kJ/mol). Anchoring of the MB molecule on both surfaces was carried out by means of two protons in a bidentate chelating (BC) adsorption model. The high adsorption energy of the MB dye on the ZnTiO3 surface shows the potential value of using this mixed oxide as a dye adsorbent for several technological and environmental applications.

9.
Artículo en Inglés | MEDLINE | ID: mdl-33807765

RESUMEN

The concept of the Mediterranean Diet has substantially evolved in the last decade and a half. From a model focused uniquely on nutrition and public health, in recent years, and after its registration as Intangible Heritage of the Humanity by the United Nations Educational, Scientific and Cultural Organization (UNESCO), its conception incorporated important elements related to society, culture, and sustainability. In this regard, the use of concepts such as commensality (or conviviality around food, or eating together), linked to a more cultural vision of food, began to be one object of attention. The aim of this article is to reflect on the role of these "new" elements regarding the actual definitions of the Mediterranean diet and, particularly, its relationship with other significant discourses inside this concept, as the preponderant of health, or the emergence of sustainability.


Asunto(s)
Dieta Mediterránea , Cultura , Conducta Alimentaria , Estado Nutricional , Salud Pública
10.
Nanomaterials (Basel) ; 11(4)2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33915750

RESUMEN

Adsorption is an effective method of removing harmful pollutants from air and water. In the present study, zeolites prepared by sol-gel method from two Ecuadorian clays were combined with precursor clays and the ZnTiO3/TiO2 semiconductor for adsorbing methylene blue (MB) as a water contaminant. The synthesized compounds were characterized using powder X-ray diffraction, X-ray fluorescence, scanning electron microscopy, energy dispersive X-ray, and surface area measurement. These compounds were combined to form cylindrical extrudates of 0.2 cm (diameter) and 1.0 cm (length). The adsorption characteristics of the composites were measured using batch sorption studies as a function of pH, initial concentration, and contact time. The pseudo-second-order model and the Langmuir isotherm model were better suited to the adsorption process. The equilibrium state was achieved around 180 min of adsorption, and a pH of 7 was established as the optimal operating condition. The maximum adsorption values of the dye were obtained with the composites derived from G-Clay, whose average adsorption capacity was 46.36 mg g-1, in contrast with composites derived from R-Clay, whose average adsorption value was 36.24 mg g-1. The results reflect that synthesized composites could be used potentially for the removal of cationic dye from wastewater.

11.
Artículo en Inglés | MEDLINE | ID: mdl-33918238

RESUMEN

Obesity is a disease that straddles medico-nutritional, psychological, and socio-cultural boundaries. There is a clear relationship between lifestyle and obesity, and today the Mediterranean diet in the Mediterranean area may represent an interesting corrective asset. However, we should not be under any misapprehension about the model's capacity for action in non-nutritional terms. Our societies are experiencing a process of rapid change, and the Mediterranean area is no exception. The aim of this article is to present a view of obesity in the Mediterranean context from an open, mainly socio-cultural perspective, but from different points of view (medical, nutritional), seeking points of convergence and elements that contribute to the understanding of and approach to the disease in the context of the Mediterranean diet. As a public health and a multidimensional social problem, obesity must be dealt with in a holistic, open, and cross-disciplinary manner to ensure that it can be understood coherently. The only way to keep the usefulness of the Mediterranean diet within desirable limits will be our societies' vitality and interest in rapidly adapting the Mediterranean diet to social change, thus providing valid answers to today's needs.


Asunto(s)
Dieta Mediterránea , Humanos , Estilo de Vida , Obesidad/epidemiología , Salud Pública
12.
Artículo en Inglés | MEDLINE | ID: mdl-33255721

RESUMEN

BACKGROUND: Nowadays the food production, supply and consumption chain represent a major cause of ecological pressure on the natural environment, and diet links worldwide human health with environmental sustainability. Food policy, dietary guidelines and food security strategies need to evolve from the limited historical approach, mainly focused on nutrients and health, to a new one considering the environmental, socio-economic and cultural impact-and thus the sustainability-of diets. OBJECTIVE: To present an updated version of the Mediterranean Diet Pyramid (MDP) to reflect multiple environmental concerns. METHODS: We performed a revision and restructuring of the MDP to incorporate more recent findings on the sustainability and environmental impact of the Mediterranean Diet pattern, as well as its associations with nutrition and health. For each level of the MDP we provided a third dimension featuring the corresponding environmental aspects related to it. CONCLUSIONS: The new environmental dimension of the MDP enhances food intake recommendations addressing both health and environmental issues. Compared to the previous 2011 version, it emphasizes more strongly a lower consumption of red meat and bovine dairy products, and a higher consumption of legumes and locally grown eco-friendly plant foods as much as possible.


Asunto(s)
Dieta Mediterránea , Ambiente , Abastecimiento de Alimentos , Animales , Bovinos , Dieta Mediterránea/estadística & datos numéricos , Conducta Alimentaria , Abastecimiento de Alimentos/economía , Abastecimiento de Alimentos/estadística & datos numéricos , Humanos , Política Nutricional/economía , Política Nutricional/tendencias , Evaluación de Programas y Proyectos de Salud
13.
Nanomaterials (Basel) ; 10(9)2020 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-32967271

RESUMEN

Currently, the study of semiconductor materials is very promising for the photocatalytic remediation of hazardous organic substances present in the air and water. Various semiconductors have been investigated in this interesting photo-assisted methodology, among them metal oxides such as ZnO, TiO2 and their derivatives. In this study, ZnTiO3/TiO2 was synthesized by the sol-gel method using Ti(OC3H7)4 and Zn(CH3COO)2 · 2H2O as reagents. The role of several conditions such as synthesis temperature and TiO2:ZnO proportion on the morphology and purity of compounds obtained was studied, and the suitable conditions for the synthesis of photocatalysts were determined. Various techniques were used to conduct a systematic investigation on the structural, morphological, and photocatalytic properties of ZnTiO3/TiO2. Scanning Electron Microscopy (SEM) images show that ZnTiO3/TiO2 have a typical particle size of approximately 100 nm with a quasi-spherical shape. The adsorption and photocatalytic activity were investigated by the decolorization of Methylene Blue (MB) as an organic contaminant under UV irradiation both in TiO2 and ZnTiO3/TiO2 supported over some Ecuadorian clays. The materials evaluated were prepared in the shape of 0.2 cm (diameter) and 1.0 cm (length) cylindrical extrudates. The degradation percentage of MB obtained was 85% approximately after 150 min of irradiation. The results obtained allow us to conclude that these synthesized materials can be used as adsorbents and photocatalysts.

14.
Water Sci Technol ; 79(7): 1276-1286, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31123227

RESUMEN

This paper is built on the Fenton-like oxidation of p-hydroxybenzoic acid (p-HBZ) in the presence of H2O2 and 3%Fe supported on CeO2-TiO2 aerogels under mild conditions. These catalysts were deeply characterized by X-ray diffraction (XRD), hydrogen temperature programmed reduction (H2-TPR), transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM) and X-ray photoelectron spectroscopy (XPS). The effect of thermal treatment, pH (2-3, 5, 7), H2O2/p-HBZ molar ratio (5, 15, 20, 25) and reaction temperature (25 °C, 40 °C and 60 °C) on the catalytic properties of supported Fe catalysts are studied. Our results highlight the role of CeO2 and the calcination of the catalyst to obtain the highest catalytic properties after 10 min: 73% of p-HBZ conversion and 52% of total organic carbon (TOC) abatement.


Asunto(s)
Hidroxibenzoatos/química , Catálisis , Peróxido de Hidrógeno/química , Hierro/química , Oxidación-Reducción , Difracción de Rayos X
15.
Nutrients ; 11(3)2019 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-30889891

RESUMEN

The Mediterranean Diet (MedDiet) has been promoted as a means of preventing and treating cardiodiabesity. The aim of this study was to answer a number of key clinical questions (CQs) about the role of the MedDiet in cardiodiabesity in order to provide a framework for the development of clinical practice guidelines. A systematic review was conducted to answer five CQs formulated using the Patient, Intervention, Comparison, and Outcome (PICO) criteria. Twenty articles published between September 2013 and July 2016 were included, adding to the 37 articles from the previous review. There is a high level of evidence showing that MedDiet adherence plays a role in the primary and secondary prevention of cardiovascular disease (CVD) and improves health in overweight and obese patients. There is moderate-to-high evidence that the MedDiet prevents increases in weight and waist circumference in non-obese individuals, and improves metabolic syndrome (MetS) and reduces its incidence. Finally, there is moderate evidence that the MedDiet plays primary and secondary roles in the prevention of type 2 diabetes mellitus (T2DM). The MedDiet is effective in preventing obesity and MetS in healthy and at-risk individuals, in reducing mortality risk in overweight or obese individuals, in decreasing the incidence of T2DM and CVD in healthy individuals, and in reducing symptom severity in individuals with T2DM or CVD.


Asunto(s)
Enfermedades Cardiovasculares/prevención & control , Diabetes Mellitus Tipo 2/prevención & control , Dieta Mediterránea , Conducta Alimentaria , Síndrome Metabólico/prevención & control , Obesidad/prevención & control , Enfermedades Cardiovasculares/dietoterapia , Diabetes Mellitus Tipo 2/dietoterapia , Humanos , Síndrome Metabólico/dietoterapia , Obesidad/dietoterapia , Sobrepeso , Prevención Secundaria , Circunferencia de la Cintura , Aumento de Peso
16.
J Dermatol Case Rep ; 11(1): 9-11, 2017 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-28539983

RESUMEN

BACKGROUND: Skin metastases occur in 0.7% to 9% of all patients with cancer and are usually considered a late event in the evolution of most visceral carcinomas. The development of a nodular metastatic lesion on the nasal tip is known as clown nose sign. MAIN OBSERVATION: We report a 64-year-old man that developed a nodular lesion on his nasal tip as first manifestation of squamous lung carcinoma. CONCLUSION: The biopsy of the cutaneous metastasis may be helpful to histopathologically confirm the suspected primary tumour avoiding invasive diagnostic procedures.

17.
J Colloid Interface Sci ; 469: 263-268, 2016 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-26896774

RESUMEN

Quartz crystal microbalance with dissipation (QCM-D) analysis of the hexa-l-Leucine (PLL)-catalyzed epoxidation of chalcone gives in-situ experimental evidences which demonstrate that the reaction proceeds mainly via the formation of a PLL-bound hydroperoxide complex followed by the reversible addition of chalcone. The observations offer an alternative rationalization for the viability of the preferred catalytic pathway.

18.
Langmuir ; 31(13): 3952-7, 2015 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-25751745

RESUMEN

Monodisperse Pd2Sn nanorods with tuned size and aspect ratio were prepared by co-reduction of metal salts in the presence of trioctylphosphine, amine, and chloride ions. Asymmetric Pd2Sn nanostructures were achieved by the selective desorption of a surfactant mediated by chlorine ions. A preliminary evaluation of the geometry influence on catalytic properties evidenced Pd2Sn nanorods to have improved catalytic performance. In view of these results, Pd2Sn nanorods were also evaluated for water denitration.

19.
N Biotechnol ; 30(6): 788-92, 2013 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-23689043

RESUMEN

Reduction of soluble uranium(VI) to insoluble uranium(IV) for remediating a uranium-contaminated effluent (EF-03) was examined using a biotic and abiotic integrated system. Shewanella putrefaciens was first used and reduced U(VI) in a synthetic medium but not in the EF-03 effluent sample. Subsequently the growth of autochthonous microorganisms was stimulated with lactate. When lactate was supported on active carbon 77% U(VI) was removed in 4 days. Separately, iron nanoparticles that were 50 nm in diameter reduced U(VI) by 60% in 4 hours. The efficiency of uranium(VI) removal was improved to 96% in 30 min by using a system consisting of lactate and iron nanoparticles immobilized on active carbon. Lactate also stimulated the growth of potential uranium-reducing microorganisms in the EF-03 sample. This system can be efficiently used for the bioremediation of uranium-contaminated effluents.


Asunto(s)
Ácido Láctico/farmacología , Nanopartículas , Shewanella putrefaciens/metabolismo , Uranio/metabolismo , Contaminantes Químicos del Agua/metabolismo , Contaminantes Radiactivos del Agua/metabolismo , Biodegradación Ambiental , Ácido Láctico/metabolismo , Oxidación-Reducción , Shewanella putrefaciens/crecimiento & desarrollo
20.
Biotechnol Prog ; 29(1): 31-8, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23074037

RESUMEN

Glycerol is an attractive substrate for biohydrogen production because, in theory, it can produce 3 mol of hydrogen per mol of glycerol. Moreover, glycerol is produced in substantial amounts as a byproduct of producing biodiesel, the demand for which has increased in recent years. Therefore, hydrogen production from glycerol was studied by dark fermentation using three strains of bacteria: namely, Enterobacter spH1, Enterobacter spH2, and Citrobacter freundii H3 and a mixture thereof (1:1:1). It was found that, when an initial concentration of 20 g/L of glycerol was used, all three strains and their mixture produced substantial amounts of hydrogen ranging from 2400 to 3500 mL/L, being highest for C. freundii H3 (3547 mL/L) and Enterobacter spH1 (3506 mL/L). The main nongaseous fermentation products were ethanol and acetate, albeit in different ratios. For Enterobacter spH1, Enterobacter spH2, C. freundii H3, and the mixture (1:1:1), the ethanol yields (in mol EtOH/mol glycerol consumed) were 0.96, 0.67, 0.31, and 0.66, respectively. Compared to the individual strains, the mixture (1:1:1) did not show a significantly higher hydrogen level, indicating that there was no synergistic effect. Enterobacter spH1 was selected for further investigation because of its higher yield of hydrogen and ethanol.


Asunto(s)
Citrobacter/metabolismo , Enterobacter/metabolismo , Fermentación , Glicerol/metabolismo , Hidrógeno/metabolismo , Citrobacter/química , Enterobacter/química , Hidrógeno/química , Factores de Tiempo
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