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The high levels of heavy metals contained in residual water and the pollution generated by a large amount of unexploited agro-industrial waste are a serious problem for the environment and mankind. Therefore, in the present work, with the aim of treating and reducing the pollution caused by heavy metal ions (Pb, Cd, Zn and Cu), activated carbons (ACs) were synthesized from sugarcane bagasse (SCB) and orange peel (OP) by means of physical - chemical activation method in an acid medium (H3PO4, 85 wt%) followed by an activation at high temperature (500 and 700 °C). Thereafter, these materials were used to produce carbon foams (CF) by the replica method and to evaluate their adsorbent capacity for the removal of heavy metals from synthetic water. XRD, FTIR, DLS, BET, Zeta Potential (ζ), SEM-EDS and AAS were used to investigate their structures, surface area, pore size, morphology, and adsorption capacity. The results show that as-prepared CF have a second level mesoporous structure and AC present a micro-mesoporous structure with a pore diameter between 3 and 4 nm. The experimental adsorption capacities of heavy metals showed that the CF from OP present a better elimination of heavy metals compared to the AC; exhibiting a removal capacity of 95.2 ± 3.96% (Pb) and 94.7 ± 4.88% (Cu) at pH = 5. The adsorption values showed that the optimal parameters to reach a high metal removal are pH values above 5. In the best of cases, the minimum remaining concentration of lead and copper were 2.4 and 2.6 mg L-1, respectively. The experimental data for carbon adsorbents are in accordance with the Langmuir and BET isotherms, with R2 = 0.99 and the maximum homogenous biosorption capacity for lead and copper was Qmax = 968.72 and 754.14 mg g-1, respectively. This study showed that agro-industrial wastes can be effectively retrieved to produce adsorbents materials for wastewater treatment applications.
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Citrus sinensis , Metais Pesados , Saccharum , Poluentes Químicos da Água , Adsorção , Biomassa , Celulose , Cobre , Concentração de Íons de Hidrogênio , Resíduos Industriais , Íons , Cinética , Chumbo , Metais Pesados/análise , Água/química , Poluentes Químicos da Água/análiseRESUMO
Cellulose nanocrystals (CNCs) were isolated from two-agroindustrial wastes: sugarcane bagasse (SCB) and pinewood sawdust (PWS), to analyze their chemical, structural, morphological, and proton conduction properties in dependence of the synthesis parameters. In both sources, the isolated CNCs correspond to the monoclinic phase of cellulose type I and II. For SCB, the smallest CNCs were isolated, in a range of 3-10 nm, with 5 wt.% of NaOH and 60 °C of acid hydrolysis. PWS displayed the smallest sizes at 75 °C and 10 wt.% NaOH (40-110 nm). Membrane characterization suggests that isolated CNCs, between 75 and 90 °C of acid hydrolysis and 10 wt.% NaOH from both SCB and PWS sources, displayed an important increase in the proton conductivity, 1.23(±0.61)×10-5 and 9.26 (±0.24)×10-5 S-m-1, respectively. Thus, with proper synthesis conditions, CNCs can be potentially used as based element to obtain other proton conductor materials to fabricate PEMs.
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Structural, compositional, morphological and electrochemical characterization are important to determinate the influence of platinum in the methanol oxidation in alkaline media. These data and analysis support the research article catalytic performance of alloyed PtxPd1-x nanostructures supported on Vulcan XC-72R for the methanol oxidation in alkaline medium [1]. The data here presented included changes in the chemical composition, structure and microstructure. Also, complement data of cyclic voltammograms during activation in alkaline media as well as in presence of 1 M CH3OH to observe CO tolerance and Electrochemical Impedance Spectroscopy measurements at two different overpotentials (0.2 and 0.3 mV) on the onset potential for methanol electro-oxidation are published in this paper. The data can be used as a reference to determinate the effect of added different amounts of Pd to Pt/C catalysts, using an organometallic compounds method and octylamine as stabilizer. The data provided in this article have not been previously published and are available to enable critical or extended analyses.
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The data set presented here offers evidence of the elemental composition related to a SEM micrograph of [Mn5(PO3(OH))2(PO4)2â 4H2O] (MnPhos) powders, known as hurealite, and synthesized by the reflux method. In addition, it contains additional information of the glass transition, melting and decomposition temperatures and their weight loss percent of coatings based on MnPhos incorporated into waterborne poly(urethane) (WPU). These data are complementing of the article "Corrosion investigation of new hybrid organic/inorganic coatings for carbon steel substrates: electrochemical and surface characterizations".
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The data presented in this article are related to the research previously published "improvement of adhesion and barrier properties of biomedical stainless steel by deposition of YSZ coatings using RF magnetron sputtering". It contains the structural, morphological, compositional and electrochemical characterization of bare AISI 316L substrate which was used as a substrate to coat with yttria-stabilized zirconia (YSZ). The chemical composition and topography analyses from X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES) and micrographs from atomic force microscopy (AFM) as well as the roughness value of the YSZ-sputtered coating on AISI 316L substrates are presented as complementary data of the article.
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The treatment of agroindustrial residues is an alternative to waste management and obtain products with added value. In this article, we describe the confocal microscopy images, the microbiological data, policosanol content and color measurement linked to the paper "production of dietary fibers from sugarcane bagasse and sugarcane tops using microwave - assisted alkaline treatments". The data contain photographs after elaboration of noodles-type pasta and chapatti-type fermented bread; the confocal laser scanning micrographs, before and after including sugarcane bagasse and sugarcane tops fibers in foods. Microbiological analyses of total coliforms, molds and yeasts, and aerobic mesophiles were also presented according to Mexican Standard NOM- 247-SSA1-2008 which confirmed that the food is safe for human consumption. The data provided in this article have not been previously published and are available to enable critical or extended analyses.
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These data display evidence of the fracture through the morphologies and the topographical features as well as roughness data of different ratios of R(recycled)-PET/PLA, PET(virgin)/PLA, PET(virgin)/Chitosan and R(recycled)-PET/chitosan. Also, data of the morphologies after degradation under accelerated weathering test and degradation mechanisms are revealed. The data supplement the article "Comparative assessment of miscibility and degradability on PET/PLA and PET/chitosan blends".
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Structural and microstructural characterization combined with vibrational, rotational modes are quite important to determinate reduction degree during synthesis of reduced graphene oxide. These data and analysis support the research article "Electrochemical alternative to obtain reduced graphene oxide by pulse potential: effect of synthesis parameters and study of corrosion properties" (López-Oyama et al., 2018). The data and analysis presented here included raw data for selected reduction potentials (V SCE) and different temperatures values (°C). Transmission electron microscopy (TEM) images of the exfoliated graphite are shown to corroborate the effect of the applied voltage to obtain electrochemically reduced graphene oxide (ERGO) on commercial 304L stainless steel (304L SS). The data provided in this article has not been previously published and are available to enable critical or extended analyses.
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Introducción: El estudio hemodinámico de una estenosis coronaria de severidad intermedia mediante la prueba de fracción de flujo de reserva (FFR) coronaria es fundamental en términos de eventos cardiovasculares principales a corto y largo plazo. Actualmente, no se ha publicado en este contexto la aplicación intracoronaria de levosimendán. Objetivos: Determinar los efectos hemodinámicos de la administración intracoronaria de levosimendán como vasodilatador en la prueba FFR, comparado contra adenosina intracoronaria. Material y métodos: Se estudiaron mediante FFR 48 lesiones intermedias en las coronarias epicárdicas principales. Resultados: De las 48 lesiones valoradas con FFR en relación con la aplicación de adenosina versus levosimendán intracoronarios, el porcentaje de estenosis coronaria fue del 55.83 (± 11.64), FFR adenosina intracoronaria 0.8633 (± 0.1130) y FFR levosimendán intracoronario 0.8652 (± 0.1090); coeficiente de correlación 0.9859 y correlación cuadrática 0.9720. Demostrando que la inducción de vasodilatación es semejante, incluyendo casos positivos para revascularización con relación FFR < 0.80. Conclusiones: El levosimendán intracoronario en la prueba FFR presentó semejanza en la valoración de las estenosis coronarias intermedias, comparado con adenosina intracoronaria. El levosimendán representa una alternativa favorable en la inducción de hiperemia coronaria, para normar decisiones de revascularización mediante asistencia fisiológica.
Aims: The hemodynamic study of a coronary stenosis of intermediate severity, by testing fraction flow reserve (FFR) is essential in terms of major cardiovascular events in the short and long term. Currently not published in this context the intracoronary application of levosimendan. Objectives: To determine the hemodynamic effects of intracoronary administration of levosimendan, a vasodilator in the FFR test, compared with intracoronary adenosine. Material and methods: Were evaluated by FFR, 48 intermediate lesions in major epicardial coronary arteries. Results: Of the 48 lesions with FFR assessed, the application of adenosine versus intracoronary levosimendan, the percentage of coronary stenosis was 55.83 (± 11.64), intracoronary adenosine FFR 0.8633 (± 0.1130) and 0.8652 FFR intracoronary levosimendan (± 0.1090) correlation coefficient of 0.9859 and 0.9720 quadratic correlation. Demonstrating that induction of vasodilatation is similar, including revascularization positive cases compared FFR < 0.80. Conclusions: Intracoronary levosimendan in the FFR test showed similarity in the assessment of intermediate coronary stenosis compared with intracoronary adenosine. Levosimendan is an excellent alternative in the induction of coronary hyperemia decisions to regulate physiological revascularization with assistance.
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PURPOSE: To identify clinical and biologic variables with significant impact on survival in patients with carcinomas of an unknown primary site (CUP) and to develop a simple prognostic model. PATIENTS AND METHODS: In this retrospective study, univariate and multivariate prognostic factors analyses were conducted in a population of 100 patients with CUP. Patients with features requiring well defined treatments had previously been excluded. RESULTS: Overall survival (OS) was significantly related to the following pretreatment adverse prognostic clinical factors: a poor performance status (2 or 3), weight loss more than 10% in the last six months, the presence of liver metastases and more than two metastatic sites. Two biological parameters predicted a significantly shorter survival: elevated serum levels of alkaline phosphatase and of lactate dehydrogenase. In the multivariate analysis, only two independent adverse prognostic parameters were retained: a poor performance status and the presence of liver metastases. We developed a prognostic model for OS based on the following subgroups: good prognosis (PS 0 or 1 and absence of liver metastases), intermediate prognosis (PS> or =2 or presence of liver metastases) and poor prognosis (PS> or =2 or presence of liver metastases). Median OS for the three groups was 10.8, 4 and 1.9 months respectively, p<0.0001. CONCLUSION: A simple prognostic model using performance status and presence of liver metastases was developed. It allowed the assignment of patients into three subgroups with different outcomes. Treatment strategies could be adapted for each subgroup. We think that this prognostic model could be useful and should be validated in other patient series.
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Carcinoma/diagnóstico , Carcinoma/secundário , Neoplasias Primárias Desconhecidas/diagnóstico , Neoplasias Primárias Desconhecidas/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Carcinoma/mortalidade , Feminino , Humanos , Masculino , Modelos Biológicos , Modelos Estatísticos , Análise Multivariada , Prognóstico , Estudos Retrospectivos , Albumina Sérica/metabolismo , Análise de SobrevidaRESUMO
During the initial phases of myocardial infarction the relaxation ventricular time increases. To assess the effect of metoprolol, a beta-blocker agent, on constant T, an index derived from left ventricular pressure during the isovolumic relaxation phase, 12 mongrel dogs underwent surgical ligation of the anterior descending coronary artery. Constant T, diastolic ventricular pressure, heart rate and mean arterial pressure were measured at control and after 15, 30, 60, 120 and 180 minutes after arterial occlusion. Six dogs were used as controls while the other six received 35 mg/kg/min of methoprolol, infused during 5 minutes. Untreated dogs had longer T times, higher ventricular filling pressures and hypotension at the end of the study in comparison with the treated does, who maintained diastolic function and did not show important changes of arterial pressure. The beta-blocker decreased the abnormality of relaxation time and preserved ventricular filling and systemic pressures in this model of experimental infarction.
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Antagonistas Adrenérgicos beta/farmacologia , Ventrículos do Coração/efeitos dos fármacos , Metoprolol/farmacologia , Contração Miocárdica/efeitos dos fármacos , Infarto do Miocárdio/fisiopatologia , Animais , Cães , Ventrículos do Coração/fisiopatologiaRESUMO
Although atherogenic main factors have been extensively studied, there are others whose real importance has not been well defined. There are some pathologic and immunologic evidences relating several infectious agents with the genesis or development of coronary atherosclerosis. Recently, a link has been established between Chlamydia pneumoniae and atherogenesis, due to immunological evidence of infection in human atherosclerotic lesions. We studied 16 aortic specimens obtained from necropsies performed in subjects who died with coronary heart disease. The infection of Ch. pneumoniae was determined by means of an immunofluorescent technique using a specific monoclonal murine antibody. A positive reaction was found in advanced non-ulcerated fibrolipid lesions in just 2 patients (13%), according with several other observations. It is not known the true relationship between the chlamydia infection and atherogenesis, neither if the infection starts or aggravates the atherosclerotic process or if it is an independent phenomenon.
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Arteriosclerose/patologia , Infecções por Chlamydia/patologia , Chlamydophila pneumoniae , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais , Aorta/patologia , Arteriosclerose/imunologia , Infecções por Chlamydia/imunologia , Doença das Coronárias/patologia , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-IdadeRESUMO
Mexicali dust (MD) is a mixture of particles of potassium aluminum silicates (98%) and sodium dioxide (2%) that induces pulmonary damage under experimental conditions, and is capable of inducing in vitro chromosomal alterations in exposed lymphocytes. It has been proposed as an atmospheric contaminant with pathogenic potential. Among the chromosomal alterations observed, numeric alterations were predominant. The present study was designed to evaluate the capacity of MD to induce anaphasic changes in the Balb c 3T3 cell line. Chrysotile asbestos was used as a positive control. MD was found to induce abnormal anaphases, and the percentage of abnormalities increased as the dose increased (27.41% with 20 mg/mL, 29.60% with 40 mg/mL and 37.10% with 80 mg/mL). Multipolar anaphases constituted the most frequent alteration (69.1-78.8%), followed by lagging chromosomes (18.2-29.5%) and anaphasic bridges (1.51-5.9%). The anaphasic alterations induced by MD showed differences in comparison to those observed with asbestos, especially for anaphasic bridges (10.4% vs. 1.51%, p<0.05). The capacity of MD to induce alterations reported in the process of chromosomal disjunction could explain the numeric aberrations reported previously by the authors of this paper. Therefore, these data support that MD could act as a clastogenic agent.
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Poluentes Atmosféricos/toxicidade , Compostos de Alumínio/toxicidade , Anáfase/efeitos dos fármacos , Aberrações Cromossômicas , Óxidos/toxicidade , Compostos de Potássio/toxicidade , Silicatos/toxicidade , Compostos de Sódio/toxicidade , Células 3T3 , Animais , Poeira , México , Camundongos , Camundongos Endogâmicos BALB CRESUMO
From June 1st, 1989 to May 31st, 1990, 16,987 consecutive newborns were examined at the No. 48 Gynecological Pediatric Hospital of the IMSS National Medical Center, looking for external congenital malformations including esophageal atresias, anorectal malformations and congenital hip luxations, all easily detected during a routine exploration. Each deformed newborn assigned two control patients the following two newborn babies showing no birth defects. 308 deformed newborns were detected, an incidence of 1.81%. Among the most frequent defects were midline flat hemangiomas, polyotia, Down syndrome, congenital hip luxation and myelomeningocele. The only significant statistical difference found with respect to the control group was a greater family history of defects in the case group (P less than 0.0001). When comparing our results with those from other studies, including a study done locally 15 years ago, we found differences among specific malformations: congenital hip malformation, polydactylia, foot deformities, flat hemangiomas, nevus and polyotias. Yet, the overall frequency of defects found was similar.