55 research outputs found
Production, characterization and application of activated carbon from brewer’s spent grain lignin
Different types of activated carbon were prepared by chemical activation of brewer’s spent grain (BSG) lignin using H3PO4 at various acid/lignin ratios (1, 2, or 3 g/g) and carbonization temperatures (300, 450, or 600 °C), according to a 22 full-factorial design. The resulting materials were characterized with regard to their surface area, pore volume, and pore size distribution, and used for detoxification of BSG hemicellulosic hydrolysate (a mixture of sugars, phenolic compounds, metallic ions, among other compounds). BSG carbons presented BET surface areas between 33 and 692 m2/g, and micro- and mesopores with volumes between 0.058 and 0.453 cm3/g. The carbons showed high capacity for adsorption of metallic ions, mainly nickel, iron, chromium, and silicon. The concentration of phenolic compounds and color were also reduced by these sorbents. These results suggest that activated carbons with characteristics similar to those commercially found and high adsorption capacity can be produced from BSG lignin.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq Brazil)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
Characterization of Active Sites on Carbon Catalysts
A method based on the deconvolution of TPD spectra is proposed for the characterization of surface oxygen
groups, which can act as the active sites on carbon catalysts. The method, which was previously used to
characterize activated carbons oxidized in the gas phase, has been extended and applied to other materials,
carbons oxidized in the liquid phase. It is shown that this method fits quite well the TPD experimental data
of the original activated carbon as well as the gas-phase and liquid-phase oxidized materials and is suitable
to estimate the amounts of each type of oxygen surface groups.info:eu-repo/semantics/publishedVersio
Anesthesiology Consensus in the Management of the Airway
Os consensos na gestão clínica da via aérea em anestesiologia pretendem disponibilizar informação, baseada na evidência atual ou, na falta desta, na opinião de peritos, no que respeita à abordagem da via aérea difícil previsível ou não previsível.
Reforçamos a importância da avaliação da via aérea e da identificação de potenciais problemas que possam condicionar dificuldade na sua abordagem e a adoção de uma estratégia segura que permita identificar e responder em crescendo de intervenção às dificuldades encontradas. Na impossibilidade de intubação traqueal (não intubo) otimizada e limitada a 4 tentativas, da impossibilidade de ventilar e oxigenar (não oxigeno) após 2 tentativas de usar um dispositivo supraglótico ou de uso de máscara facial inicialmente adequada é importante realizar, em tempo útil, uma cricotirotomia para assegurar oxigenação.
As situações clínicas de exceção só com planos simples, conhecidos por todos e regularmente treinados e adaptados à nossa atividade clinica podem assegurar melhores “outcomes”.
O registo destes eventos e a informação ao nosso doente da dificuldade encontrada e modo como foi resolvido o problema é essencial e constitui ainda um desafio a alargar a uma base nacional.info:eu-repo/semantics/publishedVersio
Thermogravimetric and reaction kinetic analysis of biomass samples from an energy plantation
The products of a Hungarian experimental plantation for energy crops were investigated. Young shoots of poplar clones (Populus x euramericana and Populus x interamericana), black locust (Robinia pseudoacacia), willow (Salix alba), and an herbaceous plant (Miscanthus sinensis) revealed unexpectedly similar thermal behavior in inert and oxidative atmospheres, as well. An 8-fold difference in the level of grinding did not result in substantial differences in the thermal decomposition. The effect of oxygen in the ambient gas was studied at low sample masses (0.2-0.4 mg) that excluded the overheating due to the high reaction heat of the combustion process. The presence of oxygen affects the decomposition from ca. 220 degreesC. Nevertheless, the extrapolated onset temperature of the hemicellulose decomposition is practically the same at 0, 5, and 21 V/V% oxygen. A group of 12 experiments, representing two grinding levels, three plant genera and four different heating programs were evaluated simultaneously by the method of least squares employing the model of independent pseudocomponents. All evaluated experiments were well described by the same set of kinetic parameters; only the parameters describing the peak area of the partial processes differed. A technique was recommended for the appropriate handling of the nonrandom errors in the simultaneous evaluation of experiment series
Interventional Algorithm in Gastrointestinal Bleeding-An Expert Consensus Multimodal Approach Based on a Multidisciplinary Team
The approach to the patient with gastrointestinal bleeding (GIB) can be very complex. A multidisciplinary panel of physicians with expertise in Gastroenterology, Anesthesiology, and Transfusion Medicine worked together to provide the best knowledge and guide clinical practitioners in the real setting of health institutions, characterized by disparate availability of human and technical resources. The authors propose a global and personalized approach according to different clinical scenarios to improve the outcomes of patients with GIB, for whom the reduction of inappropriate transfusions is crucial. The goal of this document is to provide clear and objective guidance through interventional algorithms toward a goal-directed approach according to the clinical situation and supported by the latest available scientific data on GIB management in different settings.info:eu-repo/semantics/publishedVersio
Catalytic and Photocatalytic Nitrate Reduction Over Pd-Cu Loaded Over Hybrid Materials of Multi-Walled Carbon Nanotubes and TiO2
TiO2 and carbon nanotube-TiO2 hybrid materials synthesized by sol-gel and loaded with 1%Pd−1%Cu (%wt.) were tested in the catalytic and photocatalytic reduction of nitrate in water in the presence of CO2 (buffer) and H2 (reducing agent). Characterization of the catalysts was performed by UV-Vis and fluorescence spectroscopy, X-ray diffraction, temperature programed reduction, N2 adsorption, and electron microscopy. The presence of light produced a positive effect in the kinetics of nitrate removal. Higher selectivity toward nitrogen formation was observed under dark condition, while the photo-activated reactions showed higher selectivity for the production of ammonium. The hybrid catalyst containing 20 %wt. of carbon nanotubes shows the best compromise between activity and selectivity. A mechanism for the photocatalytic abatement of nitrate in water in the presence of the hybrid materials was proposed, based in the action of carbon nanotubes as light harvesters, dispersing media for TiO2 particles and as charge carrier facilitators
Bone and Cytokine Markers Associated With Bone Disease in Systemic Mastocytosis
Background
Mastocytosis encompasses a heterogeneous group of diseases characterized by tissue accumulation of clonal mast cells, which frequently includes bone involvement. Several cytokines have been shown to play a role in the pathogenesis of bone mass loss in systemic mastocytosis (SM), but their role in SM-associated osteosclerosis remains unknown.
Objective
To investigate the potential association between cytokine and bone remodeling markers with bone disease in SM, aiming at identifying biomarker profiles associated with bone loss and/or osteosclerosis.
Methods
A total of 120 adult patients with SM, divided into 3 age and sex-matched groups according to their bone status were studied: (1) healthy bone (n = 46), (2) significant bone loss (n = 47), and (3) diffuse bone sclerosis (n = 27). Plasma levels of cytokines and serum baseline tryptase and bone turnover marker levels were measured at diagnosis.
Results
Bone loss was associated with significantly higher levels of serum baseline tryptase (P = .01), IFN-γ (P = .05), IL-1β (P = .05), and IL-6 (P = .05) versus those found in patients with healthy bone. In contrast, patients with diffuse bone sclerosis showed significantly higher levels of serum baseline tryptase (P < .001), C-terminal telopeptide (P < .001), amino-terminal propeptide of type I procollagen (P < .001), osteocalcin (P < .001), bone alkaline phosphatase (P < .001), osteopontin (P < .01), and the C-C Motif Chemokine Ligand 5/RANTES chemokine (P = .01), together with lower IFN-γ (P = .03) and RANK-ligand (P = .04) plasma levels versus healthy bone cases.
Conclusions
SM with bone mass loss is associated with a proinflammatory cytokine profile in plasma, whereas diffuse bone sclerosis shows increased serum/plasma levels of biomarkers related to bone formation and turnover, in association with an immunosuppressive cytokine secretion profile.This study was supported by grants from the Instituto de Salud Carlos III (ISCIII, Spain) (PI19/01166, CIBERONC: CB16/12/00400) and Fondo Europeo de Desarrollo Regional (FEDER) (EQC2019-005419-P), within the Subprograma Estatal de Infraestructuras de Investigación y Equipamiento Científico Técnico de 2019 del Ministerio de Ciencia, Innovación y Universidades, Fundación Española de Mastocitosis (FEM, Madrid, Spain ref.: FEM2019-MAGPIX and FEM2021-SAM); Asociación Española de Mastocitosis y Enfermedades Relacionadas (AEDM-CTMC-2019). We also thank the Biobank at the Hospital Virgen de la Salud (BioB-HVS) No. B.0000520, Toledo, Spain. TAR was supported by the 2019 European Academy of Allergy and Clinical Immunology Research Fellowship award. We thank our patients for their willingness to participate in this study
Thermal Decomposition of Wheat, Oat, Barley, and Brassica carinata Straws. A Kinetic Study
Materiales de carbón como catalizadores para la ozonización de contaminantes orgánicos en agua
[EN] A brief overview about the use of carbon materials as
metal free ozonation catalysts is presented. Carbon
materials (activated carbons, carbon xerogels, carbon
nanofibers and carbon nanotubes) have been shown
to be active catalysts in the ozonation of a wide range
of organic pollutants. Carbon materials with surface
basic properties (i.e. high electron density) and with
large pores are the most promising for this process.[ES] En el presente trabajo se resume brevemente el
uso de materiales de carbón como catalizadores
libres de metales en el proceso de ozonización. Los
materiales de carbón (carbones activados, xerogeles
de carbón, nanofibras y nanotubos de carbono) han
mostrado ser catalizadores activos para una gran
variedad de contaminantes orgánicos en dicho
proceso, siendo los más adecuados aquellos con
propiedades superficiales básicas (alta densidad
electrónica) y con mayor tamaño de poros.This work was partially supported by the European
Community’s Seventh Framework Programme
(FP7/2007-2013) under Grant Agreement No.
280658, by FEDER through COMPETE (project
PEst-C/EQB/LA0020/2013), and by QREN, ON2 and
FEDER (Project NORTE-07-0124-FEDER-0000015).
A. G. acknowledges the Grant received from FCT
(BD/45826/2008).Peer reviewe
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