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508 result(s) for "Uribe, P."
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CD80 Expression Correlates with IL-6 Production in THP-1-Like Macrophages Costimulated with LPS and Dialyzable Leukocyte Extract (Transferon®)
Transferon® is a complex drug based on a mixture of low molecular weight peptides. This biotherapeutic is employed as a coadjuvant in clinical trials of several diseases, including viral infections and allergies. Given that macrophages play key roles in pathogen recognition, phagocytosis, processing, and antigen presentation, we evaluated the effect of Transferon® on phenotype and function of macrophage-like cells derived from THP-1 monocytes. We determined the surface expression of CD80 and CD86 by flow cytometry and IL-1β, TNF-α, and IL-6 levels by ELISA. Transferon® alone did not alter the steady state of PMA-differentiated macrophage-like THP-1 cells. On the contrary, simultaneous stimulation of cells with Transferon® and LPS elicited a significant increase in CD80 (P≤0.001) and CD86 (P≤0.001) expression, as well as in IL-6 production (P≤0.05) compared to the LPS control. CD80 expression and IL-6 production exhibited a positive correlation (r=0.6, P≤0.05) in cells exposed to Transferon® and LPS. Our results suggest that the administration of Transferon® induces the expression of costimulatory molecules and the secretion of cytokines in LPS-activated macrophages. Further studies are necessary to determine the implication of these findings in the therapeutic properties of Transferon®.
ARCHAEOLOGICAL PROSPECTION WITH CORONA AND WV-3 SATELLITE IMAGERY OF THE ARCHAEOLOGICAL SITE OF ZAR TEPE (UZBEKISTAN)
The use of different data from satellite platforms for archaeological prospecting and remote sensing has been applied since the end of the 20th century. Although the current use of drones with different visible and multispectral sensors for small areas has partially replaced in some cases the use of this type of satellite information due to its higher spatial resolution. The historical importance of satellite imagery is essential to find out about and compare the transformations of the archaeological landscape of the last 60 years since the CORONA satellite program started in 1960. In this paper we propose the evaluation of a proposal for the automation of processes of two photographic reconnaissance correlative satellite programs CORONA (1960-1972), HEXAGON (1971-1986) declassified since 1995 and 2011 respectively, and the commercial satellite WorldView-3 (WV3) (2014) for use in the detection of buried archaeological structures at the archaeological site of Zar Tepe in the southeast of Uzbekistan. This is a site located in the Surkhan Darya region very little known between the first century BC and the fourth century AD. This methodology is part of the IPAEB project (International Pluridisciplinary Archaeological Expedition to Bactria) led by the University of Barcelona, the University of Salamanca and recently in 2019 the University of Zaragoza. IPAEB was started in 2006 in the South of Uzbekistan and is currently trying to explore the urban planning of the Zar Tepe archaeological site and the elements that make up its natural physical environment: evidence of communication routes, smallholdings, irrigation channels, fences and sources of raw materials.
Characterization of a Mixture of Oca (Oxalis tuberosa) and Oat Extrudate Flours: Antioxidant and Physicochemical Attributes
The oca (Oxalis tuberosa) is a tuber with high starch content and excellent antioxidant properties, which can be used in the production of extruded products; however, starch-rich products can be improved nutritionally through the incorporation of fibers that can result in extrudates with beneficial health properties. The aim of this work was to develop a mixture of oca (Oxalis tuberosa) and oat extrudate flours and evaluate the antioxidant and physicochemical attributes. The results showed that a higher moisture content increased the hardness, water absorption index, and density of the extrudates; however, the solubility and expansion indexes showed an inverse pattern. The addition of oat fiber had the opposite effect from moisture content on the physicochemical properties mentioned above. The cellular antioxidant activity (CAA) of the extrudates decreased when the oat fiber increased. An inverse pattern was observed when the moisture concentration was increased. The starch hydrolysis percentage and glycemic index decreased significantly when the fiber content increased. Oat fiber contributed 67.29% and 65.04% to these parameters, respectively. Oat fiber exerted a greater effect than moisture on the collets extruded in this study according to factor contributions.
The Vector Electric Field Investigation (VEFI) on the C/NOFS Satellite
The Vector Electric Field Investigation (VEFI) on the C/NOFS satellite comprises a suite of sensors controlled by one central electronics box. The primary measurement consists of a vector DC and AC electric field detector which extends spherical sensors with embedded pre-amps at the ends of six, 9.5-m booms forming three orthogonal detectors with baselines of 20 m tip-to-tip each. The primary VEFI measurement is the DC electric field at 16 vectors/sec with an accuracy of 0.5 mV/m. The electric field receiver also measures the broad spectra of irregularities associated with equatorial spread-F and related ionospheric processes that create the scintillations responsible for the communication and navigation outages for which the C/NOFS mission is designed to understand and predict. The AC electric field measurements range from ELF to HF frequencies. VEFI includes a flux-gate magnetometer providing DC measurements at 1 vector/sec and AC-coupled measurements at 16 vector/sec, as well as a fast, fixed-bias Langmuir probe that serves as the input signal to trigger the VEFI burst memory collection of high time resolution wave data when plasma density depletions are encountered in the low latitude nighttime ionosphere. A bi-directional optical lightning detector designed by the University of Washington (UW) provides continuous average lightning counts at different irradiance levels as well as high time resolution optical lightning emissions captured in the burst memory. The VEFI central electronics box receives inputs from all of the sensors and includes a configurable burst memory with 1–8 channels at sample rates as high as 32 ks/s per channel. The VEFI instrument is thus one experiment with many sensors. All of the instruments were designed, built, and tested at the NASA/Goddard Space Flight Center with the exception of the lightning detector which was designed at UW. The entire VEFI instrument was delivered on budget in less than 2 years. VEFI included a number of technical advances and innovative features described in this article. These include: (1) Two independent sets of 3-axis, orthogonal electric field double probes; (2) Motor-driven, pre-formed cylinder booms housing signal wires that feed pre-amps within tip-mounted spherical sensors; (3) Extended shadow equalizers (2.5 times the sphere diameter) to mitigate photoelectron shadow mismatch for sun angles along the boom directions, particularly important at sunrise/sunset for a low inclination satellite; (4) DC-coupled electric field channels with “boosted” or pre-emphasized amplitude response at ELF frequencies; (5) Miniature multi-channel spectrum analyzers using hybrid technology; (6) Dual-channel optical lightning detector with on-board comparators and counters for 7 irradiance levels with high-time-resolution data capture; (7) Spherical Langmuir probe with Titanium Nitride-coated sensor element and guard; (8) Selectable data rates including 200 kbps (fast), 20 kbps (nominal), and 2 kbps (low for real-time TDRSS communication); and (9) Highly configurable burst memory with selectable channels, sample rates and number, duration, and precursor length of bursts, chosen based on best triggering algorithm “score”. This paper describes the various sensors that constitute the VEFI experiment suite and discusses their operation during the C/NOFS mission. Examples of data are included to illustrate the performance of the different sensors in space.
Antibacterial activity of ZnO nanoparticle coatings formed by electrophoretic deposition
The scientific community is focused on the development and use of new nanomaterials to create novel devices and systems that can be useful to solve problems or provide services. Among all nanomaterials, semiconductors allow improving optical, electrical, and catalytic properties of several surfaces, including the corrosion resistance of the materials; corrosion causes several problems and economic losses in the food, pharmaceutical, and hospital industries because the materials selected must be durable, economic, and as innocuous as possible. Zinc oxide (ZnO) is one of the most interesting materials, is a photo-chemically active n-type semiconductor and has particular defects into intrinsic lattices, such as Zn and O vacancies. Herein, we use electrophoretic deposition (EPD) for the synthesis of nanostructured films composed of ZnO nanoparticles (ZnONPs) as a protective coating on low-alloy carbon steel. The electrochemical stability of the coated steel was evaluated and compared with the response of the bare steel. This work used NPs formed in homogeneous media and in reverse micelles (RMs) formed in our previous published report. The coatings were synthesized on the surface of SAE 1020 carbon steel electrodes with 12 mm diameter. As results, two different colloidal systems were formed, by RMs we synthesized high mono-dispersed and spherical 3-5 nm ZnONPs, and by homogeneous media anisotropic 20-100 nm ZnONPs, both systems with excellent fluorescence emission at different excitation wavelengths. The electrochemical evaluation confirms the stability of the coatings obtained, improving the corrosion resistance of the low-alloy carbon steel. We found that the coating obtained with the smallest particles shows better protective properties; the difference between both coatings could be related to the force balance during the electrophoretic deposition, where the friction force, that is against the electrophoretic movement, is proportional to the particle size, reducing the amount of deposited material.
Use of the fluorescent dye tetramethylrhodamine methyl ester perchlorate for mitochondrial membrane potential assessment in human spermatozoa
Summary Mitochondrial membrane potential (ΔΨm) is an indicator of sperm quality and its evaluation complements the standard semen analysis. The fluorescent dye JC‐1 has been widely used to assess sperm ΔΨm; however, some problems have been detected under certain experimental conditions. Another fluorescent compound, tetramethylrhodamine methyl ester perchlorate (TMRM), has been used in somatic cells and bovine spermatozoa but not in human spermatozoa. TMRM accumulates in hyperpolarised mitochondria and the fluorescence intensity of this compound correlates with ΔΨm. Thus, the aim of this study was to evaluate and validate the usefulness of the fluorescent dye TMRM for measuring sperm ΔΨm. The results showed that TMRM accurately detects sperm populations displaying either high or low ΔΨm. Moreover, TMRM was able to measure sperm ΔΨm under the experimental conditions in which JC‐1 had previously presented difficulties. Differences in ΔΨm according to sperm and semen quality were properly detected and a positive correlation between ΔΨm and conventional semen parameters was observed. Finally, a positive correlation was found between the ΔΨm measurement by TMRM and by the widely used JC‐1. In conclusion, TMRM is a simple, time‐effective method, easy to set in laboratories equipped with flow cytometry technology, and can accurately detect changes in ΔΨm with efficiency comparable to JC‐1 without its limitations.
ROCK ART RECORDING IN KHATM AL MELAHA (UNITED ARAB EMIRATES): MULTIRANGE DATA SCANNING AND WEB MAPPING TECHNOLOGIES
The application of geometric recording data and representation of open-air rock art is intrinsically so heterogeneous that new online web platforms are required for a more efficient analysis to link all the geo-referenced information and facilitate its scientific study. From 2015 to 2018, three geometric documentation campaigns led by the Departamento de Ingeniería Topográfica y Cartografía of the Universidad Politécnica de Madrid (Spain) were completed in the area of Khatm al Melaha (Emirate of Sharjah, United Arab Emirates) along the Gulf of Oman. More than 370 rock art engraved motifs were documented in this area close to the southwest border with the Sultanate of Oman. All those figures were picked in 149 stone blocks with different dimensions and morphologies, distributed along the slope of an isolated 58-meter-high elevation. The aim of this project was to establish a protocol for the recording, analysis, preservation and prevention of this set of open-air rock art engravings with the following actions: developing an aerial and terrestrial recording data documentation, creating and developing a web platform called threeDcloud for visualizing three-dimensional models and web mapping, and integrating a data base by means of different JavaScript open-source libraries.
Nitrosative stress by peroxynitrite impairs ATP production in human spermatozoa
Summary The most toxic species in live systems include reactive nitrogen species such as peroxynitrite, which at high levels induces nitrosative stress. In human spermatozoa, the negative effect of peroxynitrite on motility and mitochondrial membrane potential was recently demonstrated, and the hypothesis of this work is that impairment of ATP production could be one cause of the effect on motility. Therefore, the aim here was to evaluate ATP production by both glycolysis and oxidative phosphorylation (OXPHOS) in spermatozoa exposed to peroxynitrite in vitro. Human spermatozoa were incubated with SIN‐1, a molecule which generates peroxynitrite, and the ATP level was evaluated. Then, to inactivate glycolysis or OXPHOS, spermatozoa were incubated with pharmacological inhibitors of these pathways. Spermatozoa treated for inactivating one or the other pathway were exposed to SIN‐1, and the ATP level was compared to the control without SIN‐1 in each condition. The ATP level fell after peroxynitrite exposure. The ATP in spermatozoa treated for inactivating one or the other metabolic pathway and subsequently exposed to peroxynitrite was reduced compared with the control. These results show for the first time that an important mechanism by which peroxynitrite reduces sperm function is the inhibition of ATP production, affecting both glycolysis and OXPHOS.
Nutritional Characterization of Prosopis laevigata Legume Tree (Mesquite) Seed Flour and the Effect of Extrusion Cooking on its Bioactive Components
Mesquite (Prosopis laevigata) is a legume tree widely distributed in Aridoamerica. The mature fruit of this legume is a pod, which is currently underutilized and has high nutritional potential. In the present work, mesquite seed flour is described in terms of its nutritional value, as well as the effect of extrusion cooking on its bioactive components. Mesquite seed flour is rich in fiber (7.73 g/100 g) and protein (36.51 g/100 g), with valine as the only limiting amino acid. Total phenolic compound contents in raw and extruded seed flour were 6.68 and 6.46 mg of gallic acid equivalents/g (mg GAE/g), respectively. 2-2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity values in raw and extruded seed flour were 9.11 and 9.32 mg of ascorbic acid equivalent/g (mg AAE/g), respectively. The absorbance at 290 nm, as an indicator of generation of Maillard reaction product (MRP), was the same for raw and extruded samples. Apigenin was the only flavonoid found in mesquite seed flour (41.6 mg/kg) and was stable in the extrusion process. The water absorption index (WAI) and water solubility index (WSI) were changed significantly during extrusion. The expansion of mesquite seed flour extrudates was null due to the high protein and fiber content in the sample. Extrusion cooking of mesquite seed flour is a useful form of technology for the industrialization of this underutilized and nutritionally valuable legume.