675 research outputs found
Studies of Reinforced Concrete Beams and Slabs Reinforced with Steel Plates
United States Air ForceContract AF 33(600)-3131
Design, construction and evaluation of a 3D printed electrochemical flow cell for the synthesis of magnetite nanoparticles
A 3D-printed prototype of an electrochemical flow cell for the synthesis of superparamagnetic magnetite nanoparticles of medium size between 15 and 30 nm was constructed and its performance was evaluated. The cell consists of a series of rectangular channels in a parallel electrode arrangement. Electrolyte flows through the channels as the electric current is supplied to the system and a combination of electrochemical and chemical reactions create the appropriate conditions for magnetite precipitation. Different electric configurations were evaluated and both energy and production efficiencies were calculated to determine the best configuration. Different flow and current values were also investigated, and all the materials were analyzed by X-ray diffraction, transmission electron microscopy, Mossbauer spectroscopy and magnetization curve measurements to determine their effect on particle morphology, composition and magnetic behavior. The best results were obtained for a parallel monopolar configuration,
with 100 mA (3 mA cm−2) passing in each two electrodes and a flow value of 30 mL min−1, yielding an energy efficiency of 5.9 kJ g−1 and a production rate of 12.1 mg min−1, approximately 6 times higher than the 100 mL standard cell previously used.
Magnetic saturation was 77.3 emu g−1, slightly lower than the bulk material (92–100 emu g−1)The authors gratefully acknowledge the scholarship for doctoral studies of Gerardo Ivan Lozano Gutierrez granted by the National Council of Science and Technology of Mexico (CONACyT). The authors are also grateful to the Ministry of Economy and Competitiveness for the project MAT2015-67557-C2-2-P. Support for a sabbatical leave for NCS from the National Council of Science and Technology of Mexico and Exportadora de Postes S.A. de C.V. are greatly appreciate
Las representaciones de los estudiantes universitarios sobre la pobreza y la intervención socio universitaria
La intervención socio educativa forma parte de las tres funciones sustantivas de las instituciones de educación superior. Uno de sus principales esfuerzos tiene que ver con la implementación de proyectos que pretenden colocar a las universidades como actores involucrados en la promoción de la justicia y la equidad y, al unísono, incidir en la formación de los estudiantes como sujetos críticos y propositivos en el planteamiento e implementación de soluciones a los múltiples problemas sociales. En el combate a la pobreza, esta pretensión hacia los estudiantes suele tomar el nombre de “compromiso social”. Esta doble intención nos invita al análisis de la relación universidad - sociedad y las implicaciones para su estudio; tarea compleja cuyos alcances se constituyen en un tramado de interrelaciones que nos llevan a la discusión en torno a la intervención socio universitaria, la cual se enmarca en un interjuego de tensiones y contradicciones sociales presentes en la realidad.ITESO, A.C
Pulmonary thromboembolism and alveolar hemorrhage as initial manifestations of systemic lupus erythematosus
Systemic lupus erythematosus (SLE) is an autoimmune disease that affects multiple organs. SLE can affect the lung, the pulmonary vasculature, and the pleura. A 38-year-old female with limb pain and ecchymosis who later developed pulmonary thromboembolism and alveolar hemorrhage is presented here. Clinical, imaging, laboratory, and histopathological evidence is presented. The patient met the European League Against Rheumatism (EULAR) and the American College of Rheumatology (ACR) criteria for SLE. Furthermore, the patient had a Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) score of 35; thus, indicating severe disease. This case is an example of concomitant venous and arterial lung complications in an SLE patient
Assessment of Seasonal Variability of Cytochemical Responses to Contaminant Exposure in the Blue Mussel Mytilus edulis (Complex)
A selected suite of cytochemical parameters in Mytilus edulis are altered in response to field and laboratory exposure to chemical contaminants. These biomarkers include lysosomal stability, nicotinamide adenine dinucleotide phosphate (NADPH)–ferrihemoprotein reductase activity, liposfuscin deposition, and accumulation of lysosomal and cytoplasmic unsaturated neutral lipid. Normal variations in physiological processes (influenced by exogenous seasonal changes in temperature, salinity, food availability, etc.) may alter the sensitivity of these biomarkers to contaminant exposure. To address this issue, M. edulis (complex) were sampled monthly from a reference nonurban site (Coupeville, Penn Cove) and a polluted urban site (Seacrest, Elliott Bay) in Puget Sound, WA, for a period of 15 months. Physiological measurements including total length, total weight, somatic and mantle weights (an indication of gonadal development and reproductive status), condition index, and the presence or absence of hemic neoplasia (HN, or leukemia) were recorded. Significant differences in lysosomal stability, lysosomal and cytoplasmic unsaturated neutral lipids, lipofuscin deposition, and NADPH–ferrihemoprotein reductase activity in cells of the digestive gland or digestive tubules were generally found in mussels taken throughout the year from Seacrest compared to mussels sampled from Coupeville, consistent with exposure to chemical contaminants. No seasonally influenced suppression of the entire suite of parameters as measures of contaminant exposure was evident. Therefore these biomarkers can be used to evaluate contaminant exposure in mussels throughout the entire year
Electrochemical behavior of Ti and Ti6Al4V in aqueous solutions of citric acid containing halides
Localization of Native Mms13 to the Magnetosome Chain of Magnetospirillum magneticum AMB-1 Using Immunogold Electron Microscopy, Immunofluorescence Microscopy and Biochemical Analysis
Magnetotactic bacteria (MTB) biomineralize intracellular magnetite (Fe3O4
) crystals surrounded by a magnetosome membrane (MM). The MM contains membrane-specific proteins that
control Fe3O4 mineralization in MTB. Previous studies have demonstrated that Mms13 is a critical
protein within the MM. Mms13 can be isolated from the MM fraction of Magnetospirillum magneticum
AMB-1 and a Mms13 homolog, MamC, has been shown to control the size and shape of magnetite
nanocrystals synthesized in-vitro. The objective of this study was to use several independent methods to definitively determine the localization of native Mms13 in M. magneticum AMB-1. Using
Mms13-immunogold labeling and transmission electron microscopy (TEM), we found that Mms13 is
localized to the magnetosome chain of M. magneticum AMB-1 cells. Mms13 was detected in direct
contact with magnetite crystals or within the MM. Immunofluorescence detection of Mms13 in M.
magneticum AMB-1 cells by confocal laser scanning microscopy (CLSM) showed Mms13 localization
along the length of the magnetosome chain. Proteins contained within the MM were resolved by
SDS-PAGE for Western blot analysis and LC-MS/MS (liquid chromatography with tandem mass
spectrometry) protein sequencing. Using Anti-Mms13 antibody, a protein band with a molecular
mass of ~14 kDa was detected in the MM fraction only. This polypeptide was digested with trypsin,
sequenced by LC-MS/MS and identified as magnetosome protein Mms13. Peptides corresponding
to the protein’s putative MM domain and catalytic domain were both identified by LC-MS/MS. Our
results (Immunogold TEM, Immunofluorescence CLSM, Western blot, LC-MS/MS), combined with
results from previous studies, demonstrate that Mms13 and homolog proteins MamC and Mam12,
are localized to the magnetosome chain in MTB belonging to the class Alphaproteobacteria. Because
of their shared localization in the MM and highly conserved amino acid sequences, it is likely that
MamC, Mam12, and Mms13 share similar roles in the biomineralization of Fe3O4 nanocrystals.National Science Foundation, grant number EAR-2038207EAR-1423939Ministerio de Economía y Competitividad, SPAIN and Fondo Europeo de
Desarrollo Regional, FEDER grant numbers CGL2010-18274 and CGL2013-4661
Exploring the possible link between the spike protein immunoglobulin G4 antibodies and cancer progression
Repeated inoculation with messenger RNA (mRNA) vaccines elicits immunoglobulin G4 (IgG4) antibody production. Such an increase in the concentration of specific and non-specific IgG4 antibodies allows the growth of some types of cancer by blocking the activation of effector immune cells. This work proposes the hypothesis that cancer growth may be indirectly promoted by increased concentrations of non-specific IgG4 antibodies by the following mechanisms: 1) IgG4 antibodies can bind to anti-tumor IgG1 antibodies and block their interaction with receptors located on effector cells, thus preventing the destruction of cancer cells, 2) IgG4 can interact with fragment crystallizable gamma receptor IIb (FcγRIIB) inhibitory receptors, thus reducing effector functions of innate immune cells, and 3) targeting of specific epitopes by IgG4 could be oncogenic by inducing the production of a microenvironment that can promote cancer development. This article reviews the supporting literature and suggests several experimental protocols to evaluate this hypothesis in the context of repeated inoculation with mRNA vaccines. Additionally, this work proposes some management options aimed at reducing the unfavorable molecular consequences that could mediate cancer development when encountering high concentrations of IgG4 antibodies
Heterostructure Engineering of a Reverse Water Gas Shift Photocatalyst
To achieve substantial reductions in CO2 emissions, catalysts for the photoreduction of CO2 into value‐added chemicals and fuels will most likely be at the heart of key renewable‐energy technologies. Despite tremendous efforts, developing highly active and selective CO2 reduction photocatalysts remains a great challenge. Herein, a metal oxide heterostructure engineering strategy that enables the gas‐phase, photocatalytic, heterogeneous hydrogenation of CO2 to CO with high performance metrics (i.e., the conversion rate of CO2 to CO reached as high as 1400 µmol g cat−1 h−1) is reported. The catalyst is comprised of indium oxide nanocrystals, In2O3−x(OH)y, nucleated and grown on the surface of niobium pentoxide (Nb2O5) nanorods. The heterostructure between In2O3−x(OH)y nanocrystals and the Nb2O5 nanorod support increases the concentration of oxygen vacancies and prolongs excited state (electron and hole) lifetimes. Together, these effects result in a dramatically improved photocatalytic performance compared to the isolated In2O3−x(OH)y material. The defect optimized heterostructure exhibits a 44‐fold higher conversion rate than pristine In2O3−x(OH)y. It also exhibits selective conversion of CO2 to CO as well as long‐term operational stability
Psicoterapia contemporánea: dilemas y perspectivas
Hablar de una psicoterapia contemporánea nos conduce necesariamente a abordajes en clave de complejidad que favorezcan miradas más abiertas, con más posibilidades, en su constitución, su ámbito de conocimiento, el ejercicio profesional y la formación de psicoterapeutas. Y pensarla desde una perspectiva interdisciplinar es fundamental para la comprensión, el análisis y las posibilidades de tratamiento de los problemas psicológicos que aquejan a las sociedades contemporáneas. Este es el planteamiento central que se desarrolla en esta obra conformada por ocho ensayos, en los cuales se abordan temas como la formación de los psicoterapeutas, la historia de este campo profesional, la influencia del entorno y de la familia en el consultante, así como la importancia del diálogo con otras disciplinas para el perfeccionamiento de este campo de generación e innovación en psicoterapia. Por ello, se recomienda la lectura de este volumen, el primero de la colección Psicoterapia y Diálogo Interdisciplinario, a estudiantes, docentes y profesionales en el campo de la psicoterapia y la salud mental, ya que este ejercicio profesional cobra cada día mayor relevancia para el entendimiento y abordaje de la complejidad de la vida humana hacia la promoción del bienestar.ITESO. A.C
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