1,083 research outputs found

    Characterization, Classification and Authentication of Honey by Non-Targeted UHPLC-HRMS Chromatographic Fingerprints and Chemometric Methods

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    Honey is a natural substance produced by bees of the genus Apis. Depending on the raw material used for its production, honey can be classified into two large groups: blossom honey, which results from the metabolization of nectar extracted from flowers; and honeydew honey, in which bees use plant or insect secretions for its production. The physicochemical characteristics are different between these two types of honey. For example, honeydew honey is darker and is characterized by a high content of phenolic acids. On the contrary, blossom honey stands out for its abundance of flavonoids. Blossom honey can be also classified based on the pollen origin. Thus, honey with more than 45% of the pollen coming from the same species can be considered monofloral; otherwise, it is considered multifloral. Honey is one of the food products with the highest level of fraudulent practices. Most of the adulterations consist of ingredient dilution, adding sweet substances, such as syrups, sugar cane, or corn syrup, among others. In the market, this was reflected in the dubious drop in prices for this product. In the last few years, several instance of honey fraud have come to light. This work aimed to develop a non-targeted ultra-high-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) fingerprinting method to address the characterization, classification, and authentication of Spanish honey samples considering their botanical and geographical origin. A total of 136 kinds of honey from different Spanish production regions belonging to different botanical varieties were analyzed, including: blossom honey (orange blossom, rosemary, thyme, eucalyptus, and heather) and honeydew honey (holm oak, forest, and mountain). A simple sample treatment was carried out, consisting of dissolving 1 g of honey in 10 mL of water, followed by a 1:1 dilution with methanol. The chromatographic separation of the obtained extracts was performed using a Kinetex® C-18 core-shell column (100 × 4.6 mm I.D., 2.6 μm), working under gradient elution, using an aqueous solution of 0.1% formic acid and acetonitrile as the mobile phase components. HRMS acquisition was performed using electrospray in negative ionization mode (−2500 V) in an LTQ-Orbitrap working in full scan MS (m/z 100-1000) at a resolution of 50,000 full-width at half maximum (FWHM). The obtained non-targeted UHPLC-HRMS fingerprints (peak signals as a function of retention time and m/z) were considered as chemical descriptors of the analyzed honey samples for principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA). PLS-DA revealed good discrimination between blossom and honeydew honey. Furthermore, the obtained chemometric models allowed the achievement of very good classification among the different botanical varieties under study for both blossom and honeydew honey. The discrimination of honey regarding the different Spanish climate production regions was more limited, although some trends were observed. Thus, the non-targeted UHPLC-HRMS fingerprinting approach proved to be an appropriate methodology to address honey characterization, classification, and authentication based on their different botanical origin

    Soil pH effects on the Toxicity of zinc oxide nanoparticles to soil bacterial communities.

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    The environmental levels of ZnO nanoparticles (nZnO) are increasing continually given the widespread and expanding applications of this material. Soil pH appears to be one of the key factors affecting the behavior and toxicity of metal nanoparticles in soi

    Influence of the Synthesis Method on the Preparation Composites Derived from TiO2-LDH for Phenol Photodegradation

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    Three different TiO2 catalysts are prepared using different methods. MgAl-CO32− layered double hydroxides (LDH) were obtained by the sol-gel method. In the preparation of the composites, the three photocatalysts were combined with LDH following different methodologies. The composites were characterized using X-ray diffraction (XRD), specific surface area (SA), atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The influence of the synthesis method on the preparation of the composites was evaluated by analyzing their photocatalytic activity against phenol as a model organic pollutant under UV irradiation. The photocatalytic activity of the composites improves when the chemical interaction, determined by XPS, between the TiO2 and the LDH decreases. The same happens when the ratio of the anatase-rutile phases, determined by XRD, approaches optimum (80:20%). The effect of the composite concentration in the solution (0.5–2.0 g/L) was investigated, and the light-shielding phenomenon due to high composite concentration decreases the phenol photodegradation. The reduction of photocatalytic activity in reuse cycles is due to loss and partial deactivation of the material. The elimination of phenol is attributed primarily to the photocatalytic process due to the generation of ●OH radicals and to a lesser extent the adsorption process also present in the samples

    Procedia CIRP

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    During the manufacturing process of a product, variability in its parts is unavoidable. Tolerance analysis allows estimating the consequences of the component's deviation of a mechanism on its functionality. Nowadays, it is possible to determine the contribution of each surface and/or contact on the final result in isostatic mechanisms by using the tools already presented in the literature; however, it is still a challenge to do so in over-constrained mechanisms. In previous works, we introduced a method based on prismatic polyhedra to model over-constrained mechanisms. In this paper, several simulations based on the previous approach are performed, varying the tolerances of the surfaces and contacts of the mechanism. The use of statistical methods to analyze the previous simulations’ data is proposed to quantify the contribution of local deviations with respect to the total variation of the mechanism. This analysis determines the most relevant contacts, hence the most critical parts of the mechanism. The process is applied to a pump as an over-constrained case study and uses the prismatic polyhedra method for tolerance analysis

    Neutral red retention time assay in determination of toxicity of nanoparticles

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    The neutral red retention time (NRRT) assay is useful for detecting decreased lysosomal membrane stability in haemocytes sampled from bivalves, a phenomenon often associated with exposure to environmental pollutants including nanomaterials. Bivalves are popular sentinel species in ecotoxicology and use of NRRT in study of species in the genus Mytilus is widespread in environmental monitoring. The NRRT assay has been used as an in vivo test for toxicity of carbon nanoparticles (Moore MN, Readman JAJ, Readman JW, Lowe DM, Frickers PE, Beesley A. 2009. Lysosomal cytotoxicity of carbon nanoparticles in cells of the molluscan immune system: An in vivo study. Nanotoxicology. 3 (1), 40-45). We here report application of this assay adapted to a microtitre plate format to a panel of metal and metal oxide nanoparticles (2 ppm). This showed that copper, chromium and cobalt nanoparticles are toxic by this criterion while gold and titanium nanoparticles are not. As the former three nanoparticles are often reported to be cytotoxic while the latter two are thought to be non-cytotoxic, these data support use of NRRT as a general in vitro assay in nanotoxicology

    Descripción de la cohorte PROCOAC (PROspective COhort of A Coruña): Cohorte prospectiva española para el estudio de la osteoartritis

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    [Abstract] Introduction and objective: The use of well characterized osteoarthritis (OA) cohorts is mandatory for the study and knowledge of this disease. Currently, there is no prospective cohort in this pathology in Spain. The objective of this work is to describe the first osteoarthritis cohort in Spain, PROCOAC (Cohort PROspectiva de A Coruña). Methods: The Unit of Rheumatology of the University Hospital of A Coruña started a prospective follow-up study in 2006. The patient inclusion criteria were: I) Patients older than 55 years who underwent an abdominal x-ray to study both hips II) Patients diagnosed with radiographic hand OA according to ACR criteria III) Patients diagnosed with radiographic knee or hip OA according to ACR criteria. Follow-up was performed every two years collecting clinical, analytical, genetic and radiographic information. Results: The cohort consists of 937 patients, 873 have radiographic knee OA, 783 hip OA and 679 hand OA. The mean age of the population is 63.9±8.9 years and the average BMI is 29.6±5.1. More than half of the population has high blood pressure and 17% diabetes. The predominant osteoarthritis in the hand is nodular (78.1%), followed by trapeziometacarpal (55.3%) and erosive (18.4%). Twenty-one point four percent and 43.1% are healthy at knee and hip level respectively; observing a grade 1 in 26% and 37%; a grade 2 in 26.7% and 11.5%; a grade 3 in 14.9% and 4%; and a grade 4 in 9.4% and 3.7% respectively. Of the population, 44.1% has only 1 joint affected, 39.9% has 2 and 13.4% has 3 joints affected. Age (OR=1.11; p<.001), BMI (OR=1.11; p=.002) and total WOMAC (OR=1.03; p=.005) are the only risk factors if we compare the involvement of a single location versus three. A discrepancy between pain and radiographic damage at the joint level was also detected in patients with KL≤2 grade, and therefore a significantly higher percentage of patients with knee OA experienced pain (66.1%) compared to patients with OA hip (21.1%) (p<.001). Conclusions: The PROCOAC cohort is an instrument that allows studies of incidence and progression in hand, knee and hip OA; as well as determining factors that are associated with the different OA phenotypes.[Resumen] Introducción y objetivo. El uso de cohortes de Osteoartritis (OA) bien caracterizadas es obligatorio para estudiar y profundizar en el conocimiento en esta enfermedad. En España no existe actualmente ninguna cohorte prospectiva en esta patología; así el objetivo de este trabajo es describir la primera cohorte de Osteoartritis en España, la PROCOAC (PROspective COhort of A Coruña). Material y métodos. El Servicio de Reumatología del Hospital Universitario de A Coruña inició un estudio de seguimiento prospectivo en el año 2006. Los criterios de inclusión fueron: I) Pacientes mayores de 55 años a los que se les realizó una radiografía abdominal que permitiese estudiar ambas caderas II) Pacientes diagnosticados de OA radiográfica de mano según los criterios ACR III) Pacientes diagnosticados de OA radiográfica de rodilla y/o cadera según los criterios ACR. Se realizó seguimiento cada dos años recogiendo información clínica, analítica, genética y radiográfica. Resultados. La cohorte consta de 937 individuos, 873 tienen OA radiográfica de rodilla, 783 de cadera y 679 de mano. La edad media de la población es 63,9 ± 8,9 años y el IMC promedio de 29,6 ± 5,1. Más de la mitad de la población tiene hipertensión arterial y el 17% diabetes. La osteoartritis predominate en la mano es la nodular (78,1%), seguida de la rizartrosis (55,3%) y la erosiva (18,4%). El 21,4% y el 43,1% son sanos a nivel de rodilla y cadera respectivamente; observando un grado 1 en el 26% y 37%; un grado 2 en el 26,7% y 11,5%; un grado 3 en el 14,9% y 4%; y un grado 4 en el 9,4% y 3,7% respectivamente. El 44,1% de la población tiene 1 articulación afectada, el 39,9% tiene 2 y el 13,4% tiene 3 articulaciones afectadas. La edad (OR = 1,11; p < 0,001), el IMC (OR = 1,11; p = 0,002) y el WOMAC total (OR = 1,03; p = 0,005) son los únicos factores de riesgo si comparamos la afectación de una sola ubicación frente a tres. También se detectó una discrepancia entre el dolor y el daño radiográfico a nivel articular en pacientes con grado KL ≤ 2, de modo que un porcentaje significativamente mayor de pacientes con OA de rodilla experimentaron dolor (66,1%) en comparación con pacientes con OA de cadera (21,1%) (p < 0,001). Conclusión. La cohorte PROCOAC es un instrumento que permite realizar estudios de incidencia y pro-gresión en la osteoartritis de mano, rodilla y cadera, así como conocer factores que se asocian con losdiferentes fenotipos de osteoartritis

    Metamorfosis del Contar. Semiosis/Memoria V. Massmediación: formatos y dispositivos. 16H344

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    Se explora la prensa gráfica en soporte papel y digital como complejo mnemosemiótico y comunicativo, para dar cuenta de la conformación y las características de este tipo de dispositivo performativo. Se indaga y analiza, con un enfoque interdisciplinar (Semiótica, Análisis del Discurso, Comunicación) y desde una perspectiva crítica y política, el diario en su totalidad y el trabajo de massmediación que lleva a cabo este tipo de textualidad compleja. Se pretende describir y caracterizar el formato, sus matrices semio-discursivas y comunicativas, y relevar y analizar los diversos géneros y discursos que lo conforman

    DETECCIÓN DE ANTICUERPOS CONTRA PESTIVIRUS EN RUMIANTES DE UNA COMUNIDAD CAMPESINA DE LA PROVINCIA DE CANCHIS, CUSCO

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    El presente estudio tuvo como objetivo determinar la seroprevalencia de los pestivirus de la enfermedad de la diarrea viral bovina (DVB) y enfermedad de la frontera (EF) en rumiantes de la comunidad de Silly, provincia de Canchis, Cusco, a través de la detección de anticuerpos en el suero sanguíneo de alpacas (n=200), bovinos (n=38) y ovinos (n=45) hembras adultas, mediante la prueba de virus-neutralización. El 11.5 ± 4.4% (23/200) y el 9.5 ± 4.1% (19/200) de las alpacas presentaron anticuerpos neutralizantes contra los virus DVB y EF. El 73.7 ± 13.9% (28/38) y 76.3 ± 13.5% (29/38) de los bovinos y el 13.3 ± 9.9% (6/45) y 15.5 ± 10.6% (7/45) de los ovinos presentaron anticuerpos contra la DVB y EF, respectivamente. Estos resultados confirman la presencia de la infección pestiviral en rumiantes bajo un sistema de crianza mixto en una comunidad campesina del Cusco.The seroprevalence of bovine viral diarrhoea virus (BVDV) and border disease virus (BDV) in serum samples of alpacas (n=200), bovine (n=38) and ovine (n=45) of a rural community of Cusco, Perú was carried out by virus-neutralization test. The 11.5 ± 4.4% (23/200) and 9.5 ± 4.1% (19/200) of alpacas had neutralizing antibodies against BVD and BD virus. The 73.7 ± 13.9% (28/38) and 76.3 ± 13.5% (29/38) of bovine and the 13.3 ± 9.9% (6/45) and 15.5 ± 10.6% (7/45) of ovine had antibodies to BVDV and BDV respectively. These results confirm the presence of pestiviral infection in ruminants of a mixed breeding system in a rural community

    Brain Functional Connectivity Is Modified By A Hypocaloric Mediterranean Diet And Physical Activity In Obese Women

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    Functional magnetic resonance imaging (fMRI) in the resting state has shown altered brain connectivity networks in obese individuals. However, the impact of a Mediterranean diet on cerebral connectivity in obese patients when losing weight has not been previously explored. The aim of this study was to examine the connectivity between brain structures before and six months after following a hypocaloric Mediterranean diet and physical activity program in a group of sixteen obese women aged 46.31 +/- 4.07 years. Before and after the intervention program, the body mass index (BMI) (kg/m(2)) was 38.15 +/- 4.7 vs. 34.18 +/- 4.5 (p < 0.02), and body weight (kg) was 98.5 +/- 13.1 vs. 88.28 +/- 12.2 (p < 0.03). All subjects underwent a pre- and post-intervention fMRI under fasting conditions. Functional connectivity was assessed using seed-based correlations. After the intervention, we found decreased connectivity between the left inferior parietal cortex and the right temporal cortex (p < 0.001), left posterior cingulate (p < 0.001), and right posterior cingulate (p < 0.03); decreased connectivity between the left superior frontal gyrus and the right temporal cortex (p < 0.01); decreased connectivity between the prefrontal cortex and the somatosensory cortex (p < 0.025); and decreased connectivity between the left and right posterior cingulate (p < 0.04). Results were considered significant at a voxel-wise threshold of p <= 0.05, and a cluster-level family-wise error correction for multiple comparisons of p <= 0.05. In conclusion, functional connectivity between brain structures involved in the pathophysiology of obesity ( the inferior parietal lobe, posterior cingulate, temporo-insular cortex, prefrontal cortex) may be modified by a weight loss program including a Mediterranean diet and physical exercise

    Remote Detection of Oil Slicks at the Ocean Surface

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    The 2010 Deepwater Horizon (DWH) oil slick caused by the explosion of the Macondo well was the worst man-made disaster in the history of the Gulf of Mexico, and the largest marine spill in the history of the petroleum industry. We provide an overview of our efforts to monitor the extent of these slicks using automated algorithms for the Moderate Resolution Imaging Spectroradiometer (MODIS), and the Synthetic Aperture Radar (SAR). We discuss the advantages and limitations of each of the methods in detection of oil from space, and suggest that the NIR bands may be the best option to monitor emulsified oil when using passive sensors. Additionally, we discuss current laboratory-based efforts to measure oil thickness via holographic interferometry, and propose this as an ideal technique for future remote sensing of oil.
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