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1.
BMC Cancer ; 24(1): 668, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824512

RESUMO

BACKGROUND: Gastrointestinal cancers represent one of the most prevalent diseases worldwide. Strikingly, the incidence of Early Onset Gastrointestinal Cancer (EOGIC) has been rising during the last decades and changes in lifestyle and environmental exposure seem to play a role. EOGIC has been defined as a different entity compared to on-average gastrointestinal cancer, with distinct clinical and molecular characteristics. Inherent to the particularities of younger age, there is an unmet need for a tailored approach for the management of these patients. The TEOGIC proposes a comprehensive study to characterize EOGIC patients in the northern of Spain. METHODS: Patients with histologically confirmed new diagnosis of colorectal, gastroesophageal and pancreatic adenocarcinoma will be considered for two cohorts: EOGIC (≤ 50 years old) and non-EOGIC (60-75 years old), with a ratio of 1:2. Two hundred and forty patients will be recruited in 4 Public Hospitals from northern Spain. After receiving unified informed consent, demographic and clinical data of the patients will be collected in a REDCap database. Lifestyle related data will be obtained in questionnaires assessing diet, physical activity and the general quality of life of the patients before diagnosis. Biological samples prior to any onco-specific treatment will be obtained for the analyses of circulating inflammatory proteins, gut microbiota, and the proteome of the tumor microenvironment. Histologic characteristics and routine biomarkers will be also collected. Thereafter, data will be integrated and analyzed to assess tumor specific, pan-tumor and sex-associated differential characteristics of EOGIC. DISCUSSION: The underlying risk factors and differential characteristics of EOGIC remain poorly studied, particularly in our geographical area. Although limited by the exploratory nature and the small sample size estimated to be recruited, TEOGIC represents the first attempt to comprehensively characterize these young patients, and thus attend to their special needs. Findings derived from this study could contribute to raise awareness and preventive behaviors in the population. In parallel, molecular studies could lead to the identification of potential novel non-invasive biomarkers and therapeutic targets that would help in the development of the tailored clinical management of these patients, focusing on screening programs for early diagnosis and precision medicine.


Assuntos
Neoplasias Gastrointestinais , Humanos , Espanha/epidemiologia , Pessoa de Meia-Idade , Masculino , Feminino , Idoso , Neoplasias Gastrointestinais/epidemiologia , Neoplasias Gastrointestinais/diagnóstico , Neoplasias Gastrointestinais/patologia , Neoplasias Gastrointestinais/terapia , Adulto , Idade de Início , Estilo de Vida , Adenocarcinoma/epidemiologia , Adenocarcinoma/diagnóstico , Adenocarcinoma/patologia , Adenocarcinoma/terapia , Microambiente Tumoral , Qualidade de Vida , Incidência , Biomarcadores Tumorais , Neoplasias Esofágicas/epidemiologia , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/terapia , Neoplasias Pancreáticas/epidemiologia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patologia
2.
Exp Eye Res ; 202: 108358, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33207223

RESUMO

To restore corneal transparency and vision loss after an injury on the ocular surface, the use of human stem cells from different origins has been recently proposed. Mesenchymal stem cells (MSCs) seem to be an appropriate adult source of autologous stem cells due to their accessibility, high proliferation rate, and multipotent capacity. In this work, we developed a simple culture system to prepare a graft based on a fibrin membrane seeded with human MSCs. A commercial kit, PRGF Endoret®, was used to prepare both, the growth factors used as culture media supplement and the fibrin membrane grafts. Adipose-derived MSCs (Ad-MSCs) were expanded, characterised by flow cytometry and their multilineage differentiation potential confirmed by inducing adipogenesis, osteogenesis and chondrogenesis. Ad-MSCs seeded on the fibrin membranes were grafted onto athymic mice showing good biocompatibility with no adverse reactions observed during the follow up period. These findings support the assumption that a system in which all the biological components (cells, grow factors and carrier) are autologous, could potentially be used for future ex vivo expansion of Ad-MSCs to treat ocular conditions such as an inflammatory milieu, traumatic scars and loss of the regenerative capacity of the corneal epithelium that compromise the quality of vision.


Assuntos
Tecido Adiposo/citologia , Oftalmopatias/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Adipogenia , Adolescente , Adulto , Idoso , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Feminino , Humanos , Masculino , Células-Tronco Mesenquimais/metabolismo , Pessoa de Meia-Idade , Adulto Jovem
3.
Magn Reson Med ; 82(3): 984-999, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31045280

RESUMO

PURPOSE: High-resolution three-dimensional (3D) structural MRI is useful for delineating complex or small structures of the body. However, it requires long acquisition times and high SAR, limiting its clinical use. The purpose of this work is to accelerate the acquisition of high-resolution images by combining compressed sensing and parallel imaging (CSPI) on a 3D-GRASE sequence and to compare it with a (CS)PI 3D-FSE sequence. Several sampling patterns were investigated to assess their influence on image quality. METHODS: The proposed k-space sampling patterns are based on two undersampled k-space grids, variable density (VD) Poisson-disc, and VD pseudo-random Gaussian, and five different trajectories described in the literature. Bloch simulations are performed to obtain the transform point spread function and evaluate the coherence of each sampling pattern. Image resolution was assessed by the full-width at half-maximum (FWHM). Prospective CSPI 3D-GRASE phantom and in vivo experiments in knee and brain are carried out to assess image quality, SNR, SAR, and acquisition time compared to PI 3D-GRASE, PI 3D-FSE, and CSPI 3D-FSE acquisitions. RESULTS: Sampling patterns with VD Poisson-disc obtain the lowest coherence for both PD-weighted and T2 -weighted acquisitions. VD pseudo-random Gaussian obtains lower FWHM, but higher sidelobes than VD Poisson-disc. CSPI 3D-GRASE reduces acquisition time (43% for PD-weighted and 40% for T2 -weighted) and SAR (∼45% for PD-weighted and T2 -weighted) compared to CSPI 3D-FSE. CONCLUSIONS: CSPI 3D-GRASE reduces acquisition time compared to a CSPI 3DFSE acquisition, preserving image quality. The design of the sampling pattern is crucial for image quality in CSPI 3D-GRASE image acquisitions.


Assuntos
Compressão de Dados/métodos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Algoritmos , Encéfalo/diagnóstico por imagem , Humanos , Joelho/diagnóstico por imagem , Imagens de Fantasmas
4.
J Clin Pharm Ther ; 42(5): 638-641, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28485829

RESUMO

WHAT IS KNOWN AND OBJECTIVE: Chylous ascites is a rare condition. The most frequent causes are lymphomas, solid malignancies, abdominal trauma and cirrhosis. Isolated case reports describe the relationship between calcium channel blockers (CCB) and chyloperitoneum. Lercanidipine is a third-generation dihydropyridine with low rate of adverse events. We describe a case of lercanidipine-induced chylous ascites. CASE SUMMARY: An 80-year-old white female with hypertension treated with lercanidipine, developed chylous ascites and abdominal pain after the dosage of the CCB was doubled. The initial suspicion was a hidden neoplasm, but after a thorough research, no apparent cause was detected and the symptoms resolved after the drug was suspended. WHAT IS NEW AND CONCLUSION: Calcium channel blockers should be considered as possible causes in cases of chyloperitoneum of unknown aetiology.


Assuntos
Bloqueadores dos Canais de Cálcio/efeitos adversos , Ascite Quilosa/induzido quimicamente , Di-Hidropiridinas/efeitos adversos , Idoso de 80 Anos ou mais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/efeitos adversos , Bloqueadores dos Canais de Cálcio/administração & dosagem , Di-Hidropiridinas/administração & dosagem , Feminino , Humanos , Hipertensão/tratamento farmacológico
6.
Int J Clin Pract ; 70(2): 147-55, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26817569

RESUMO

BACKGROUND: To develop a prediction rule to describe the risk of death as a result of enterococcal bloodstream infection. METHODS: A prediction rule was developed by analysing data collected from 122 patients diagnosed with enterococcal BSI admitted to the Clínica Universidad de Navarra (Pamplona, Spain); and validated by confirming its accuracy with the data of an external population (Hospital del Mar, Barcelona). RESULTS: According to this model, independent significant predictors for the risk of death were being diabetic, have received appropriate treatment, severe prognosis of the underlying diseases, have renal failure, received solid organ transplant, malignancy, source of the bloodstream infection and be immunosuppressed. The prediction rule showed a very good calibration (Hosmer-Lemeshow statistic, P = 0.93) and discrimination for both training and testing sets (area under ROC curve = 0.84 and 0.83 respectively). CONCLUSIONS: The predictive rule was able to predict risk of death as a result of enterococcal bloodstream infection as well as to identify patients, who being below the threshold value, will have a low risk of death with a negative predictive value of 96%.


Assuntos
Bacteriemia/microbiologia , Bacteriemia/mortalidade , Técnicas de Apoio para a Decisão , Enterococcus/isolamento & purificação , Idoso , Comorbidade , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Curva ROC , Medição de Risco/métodos , Fatores de Risco , Espanha
7.
Opt Express ; 22(4): 4738-50, 2014 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-24663793

RESUMO

A cascade least-squares scheme for wrapped phase extraction using two or more phase-shifted fringe-patterns with unknown and inhomogeneous surface phase shift is proposed. This algorithm is based on the parameter estimation approach to process fringe-patterns where, except for the interest phase distribution that is a function of the space only, all other parameters are functions of both space and time. Computer simulations and experimental results show that phase computing is possible even when an inhomogeneous phase shift is induced by nonlinearity of the piezoelectric materials or miscalibrated phase shifters. The algorithm's features and its operating conditions will been discussed. Due to the useful properties of this algorithm such as the robustness, computational efficiency, and user-free execution, this proposal could be used in automatic applications.

8.
Poult Sci ; 103(7): 103828, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38795513

RESUMO

Heat stress can greatly challenge growth and meat quality of broiler chickens where research is looking for sustainable ingredients, such as microalgae, that could also alleviate its negative impacts. Thus, in the present study, 576 1-D-old chicks (Ross 308) were housed until commercial slaughtering (42 D) in 36 pens in 2 rooms of a poultry house, according to a full factorial design encompassing 2 room temperatures (standard vs. high), 2 sexes (females vs. males), and 3 dietary treatments, that is, diet C0 (control diet), diet C3, and diet C6 containing 0, 3, and 6%, respectively, of C. vulgaris meal replacing the same quantities of soybean meal. The highest inclusion level of C. vulgaris decreased feed intake (P < 0.001) and body weight (P < 0.0001) compared to the control diet; it increased yellow and red indexes (P < 0.0001) of the breast muscle, besides the proportion of n3 polyunsaturated fatty acids (PUFA) (P = 0.028). Heat stress decreased feed intake (P = 0.001), breast (P = 0.001) and p. major yields (P = 0.036), and increased meat pH (P= 0.008) and cooking losses (P < 0.001), umami (P = 0.021) and brothy flavor (P < 0.001), and the proportion of n3 PUFA rates (P = 0.027), while reducing the contents of several amino acids in the breast meat (P ≤ 0.05). Compared to females, males displayed higher feed intake and growth, and more favorable feed conversion (P < 0.001). Carcass and p. major yields were greater in females (P < 0.001) which also showed a higher occurrence of spaghetti meat compared to males (P < 0.001). In conclusion, C. vulgaris can be used to replace until 3% of soybean meal in diets for broiler chickens without negative implications, while positively affecting breast meat color according to consumers' preferences. However, the microalgae inclusion did not mitigate the negative effects of a chronic heat stress on growth performance nor reduced the occurrence of any myopathies.


Assuntos
Ração Animal , Galinhas , Chlorella vulgaris , Dieta , Suplementos Nutricionais , Carne , Animais , Ração Animal/análise , Galinhas/fisiologia , Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Masculino , Carne/análise , Feminino , Suplementos Nutricionais/análise , Chlorella vulgaris/química , Temperatura Alta , Resposta ao Choque Térmico , Distribuição Aleatória , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos
9.
J Environ Radioact ; 246: 106832, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35183925

RESUMO

Meteoric 10Be and 26Al radionuclides are produced in the atmosphere, and the relationship between them has potential applications in atmospheric and climate research. In particular, the meteoric 26Al/10Be ratio has potential applications such as a chronometer for old ice, a tracer for the air exchange between the lower stratosphere and upper troposphere, production and distribution in the atmosphere of both radionuclides, and the study on solar activity. In this work, their concentrations in the fine fraction of airborne particulate matter from an urban area have been precisely determined using Accelerator Mass Spectrometry (AMS). To obtain new data about the 26Al/10Be ratio and its subsequent applications, PM2.5 in aerosol samples has been analyzed. The average ratio in samples from Mexico City was significantly higher than those previously reported by other authors. The high enrichment factors for stable Aluminum indicate that both resuspended and anthropogenic 27Al content in PM2.5 contributes significantly to the high values of 26Al in the 26Al/10Be ratio. An adjustment of 27Al concentrations from external contributions was carried out, and the corrected 26Al/10Be ratios were similar to those previously reported. In this study, a precise assessment of the possible contribution of other Aluminum sources to the aerosol samples has been carried out. Finally, the obtained ratios indicate the possibility of its future use in applications such as the dating of glaciers.


Assuntos
Poluentes Atmosféricos , Monitoramento de Radiação , Aerossóis/análise , Poluentes Atmosféricos/análise , Atmosfera , Cidades , Monitoramento Ambiental/métodos , Material Particulado/análise
10.
Data Brief ; 42: 108256, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35599820

RESUMO

This document presents the supporting information for the evaluation of the role of Ni amount during the in situ synthesis of vulcan supported PdNi nanostructures using an organometallic approach for hydrogen evolution reaction in alkaline medium [1]. The data here presented included analysis of deconvolution during structural characterization, chemical composition and transmission electron microscopy. The information also contains complement data of cyclic voltammograms during activation in alkaline media. Supplement data of electrochemical impedance spectroscopy measurements at two different overpotentials (-100 and -300 mV) and temperatures on the onset potential for hydrogen evolution reaction (HER) are also showed in this paper. The files can be used as a reference to determinate the effect of adding different in situ amount of Ni to Pd/C catalysts in presence of 2 equivalents of hexadecylamine (HDA) in order to improve the electrochemical performance on HER using an adjusted organometallic method. The data provided in this article have not been previously published and are available to enable critical or extended analyses.

11.
Data Brief ; 43: 108410, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35811652

RESUMO

This document contains additional information for the production of activated carbons (AC) and carbon foams (CF) from agroindustrial wastes, orange peel (OP) and sugarcane bagasse (SCB). In particular, a set of data is presented for the characterization of carbonaceous structures (AC and CF) and their application in the removal of metallic ions contained in polluted waters. The adsorbent materials were obtained combining chemical and physical activation processes. Data presented here included characterization of AC and CF using dynamic light scattering (DLS), BET (Brunauer, Emmet and Teller) surface area analysis, Barrett-Joyner-Halenda (BJH) method to assess pore size distribution and zeta potential (ζ) to evaluate electrokinetic potential of carbonaceous structures. In addition, energy dispersive spectroscopy (SEM/EDS) to identify heavy metals on the surface of carbonaceous materials is shown and complementary adsorption capacity data for metal ion removal are presented in the paper. The data can be used as a reference to promote reuse of agroindustrial wastes and provide added value; particularly for the synthesis of carbonaceous structures applied to the water purification.

12.
Sci Total Environ ; 831: 154883, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35358521

RESUMO

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.


Assuntos
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/análise
13.
Clin Nephrol ; 75(4): 362-8, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21426891

RESUMO

The majority of patients with non-HIV-related collapsing focal segmental glomerular sclerosis (FSGS) have idiopathic disease. Only a few genetic forms associated with rare syndromes have been described in families. Here we report two families with multiple members who have collapsing FSGS with no clear associated secondary etiology. Genetic analysis revealed a defect in the TRPC6 gene in one family, but excluded all known common inherited podocyte defects in the other family. The course and response to treatment differed dramatically among members of the same family.


Assuntos
Glomerulosclerose Segmentar e Focal/genética , Adulto , Biópsia , Progressão da Doença , Feminino , Glomerulosclerose Segmentar e Focal/diagnóstico , Glomerulosclerose Segmentar e Focal/tratamento farmacológico , Humanos , Masculino , Linhagem
14.
J Struct Biol ; 170(1): 41-9, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20064619

RESUMO

Sea urchins have characteristic spines that fulfil critical functions. Several studies revealed marked spine internal heterogeneities at different structural levels despite the single-crystal character of the spines. Most of these studies did not speculate about the functional meaning of these heterogeneities. Spine heterogeneities were investigated in the sea urchin Paracentrotuslividus and their possible functional implications discussed. Spines mainly show two morphological parts: the base, made of a meshwork stereom, and the shaft, with longitudinal plain septa and a central core of meshwork stereom. Electron Backscatter Diffraction showed no difference in crystallite orientation between the two structures. Atomic Absorption Spectrometry and Energy dispersive X-ray analysis revealed that Mg was not uniformly distributed in the spine. Mg concentration is higher in the inner part of the septa than in the septum outer part. Furthermore, a cyclic pattern of Mg concentration in septa was observed. This is suggested to be linked to the spine ontogeny. Nano- and microindentation analyses revealed that the septa have higher stiffness and hardness than the meshwork stereom and that septum stiffness and hardness present different trends in longitudinal and transverse section. These mechanical heterogeneities may have an adaptive functional value.


Assuntos
Estruturas Animais/anatomia & histologia , Ouriços-do-Mar/anatomia & histologia , Análise de Variância , Estruturas Animais/metabolismo , Animais , Anisotropia , Fenômenos Biomecânicos , Magnésio/metabolismo , Microscopia Eletrônica de Transmissão , Ouriços-do-Mar/fisiologia , Espectrometria por Raios X , Espectrofotometria Atômica
15.
Data Brief ; 30: 105597, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32382609

RESUMO

The data shown in this document provides all the experimental data that complement the article published in Carbohydrate Polymers entitled "Influence of operating conditions on Proton Conductivity of Nanocellulose films using two Agroindustrial Wastes: Sugarcane Bagasse and Pinewood Sawdust" [1]. The data of this paper are the result of a large series of experiments to optimize the extraction of cellulose nanocrystalline (CNC) from these two agro-industrial wastes: sugarcane Bagasse (SCB) and pinewood sawdust (PSW). The conditions of pretreatment (5 wt.% or 10 wt.% of NaOH) and hydrolysis temperature (60, 75 and 90°C) in an aqueous solution of 45 wt.% of H2SO4 were analyzed exhaustively. The data includes the characterization by Fourier transform infrared (FT-IR), Differential Scanning Calorimetry/Thermogravimetric Analysis (DSC/TGA), Dynamic Light Scattering (DLS), X-ray diffraction (XRD) patterns, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) micrographs with their corresponding SAED patterns and nanoindentation tests. Additionally, photographs during the isolation of cellulose nanocrystalline in dependence of the syntheses parameters. It is also included the data that complement the molecular dynamic simulation generated by GLYCAM carbohydrate builder based on the coordinates for alpha and beta cellulose considering a microfibril of 5, 10 and 20 glucosyl residues (degree of polymerization, DP). Overall data have not been previously published and are available contributing to a better understanding of the CNCs isolation through different pretreatment concentrations and temperatures of processing.

16.
Carbohydr Polym ; 238: 116171, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32299564

RESUMO

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.

17.
Data Brief ; 29: 105172, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32055660

RESUMO

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.

18.
Data Brief ; 29: 105121, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31993471

RESUMO

The data set presented here offers evidence of the elemental composition related to a SEM micrograph of [Mn5(PO3(OH))2(PO4)2⋅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".

19.
J Struct Biol ; 167(1): 62-7, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19341799

RESUMO

Perforations ("punctae") are one of the most characteristic morphological shell features in calcite brachiopods. The significance of punctae is that they represent discontinuities in shell biomineralisation and thus add a level of complexity that must be accounted for in any model of brachiopod shell formation. A significant hindrance to understanding punctae growth and formation is the absence of sufficient information on volume, size and density. Here, we use synchrotron-radiation X-ray tomographic microscopy (SRXTM) to obtain three-dimensional information about punctae of five species of calcite brachiopods. X-ray tomography shows that punctae morphology is species-specific and reveals previously unknown levels of complexity for each species. This information is combined with previous data on morphology to discuss the function and growth of punctae. Overall the present study demonstrates the need to increase our understanding of discontinuities and the role of cell biology in the context of biomineralisation.


Assuntos
Carbonato de Cálcio/química , Invertebrados/química , Animais , Invertebrados/ultraestrutura , Microscopia Eletrônica de Varredura , Tomografia por Raios X/métodos
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