1,262 research outputs found

    Contribution From Optical Course For The Educational Guidance Of Engineering Careers Students

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    The work shows the fundamental elements of an inclusive educational guidance conception of substantive university processes and results achieved at the Instituto Superior Politécnico José Antonio Echeverría of Havana in the contribution from optical course to develop it for the students in first and second year of the engineering programs, by means of lectures on holography and three-dimensional images of motivation and link with different specialties and the development of experimental facilities and methodology for the construction of holograms and anaglyph by students for engineering applications.9289 IEEE - The Photonics Society,International Commission for Optics (ICO),The Optical Society,The Society of Photo-Optical Instrumentation Engineers (SPIE)Collazo, B., Puentes, M., La orientacin en la actividad pedaggica ¿el maestro, un orientador? (1992) Editorial Pueblo y Educacin, , La HabanaCollazo, B., (2006) Modelo de Tutora Integral Para la Continuidad de Estudios Universitarios en Las Sedes Municipals, , Tesis de doctorado CubaRodrguez, S., (1997) Orientacin Universitaria y Evaluacin de la Calidad. Calidad de la Universidad: Orientacin y Evaluacin, , Apodaca P. y C. Lobato Eds, Barcelona, LaertesEcheverra, B., (1997) Los servicios de orientacin universitarios. Calidad en la universidad: Orientacin y evaluacin, pp. 112-136. , Apodaca P. y C. Lobato (Eds, Barcelona: LaertesMonge, M.C., (2009) Tutora y Orientacin Educative, , Nuevas competencies Las Rozas Wolters KluwerSantana, L.E., (2009) Orientacin Educativa e Intervencin Psicopedaggica Cambian Los Tiempos Cambian Las Responsabilidades Profesionales, , Pirmide MadridVieira, M.J., Vidal, J., Tendencias de la Educacin Superior Europea e implicaciones para la orientacin universitaria (2006) Revista Espaola de Orientacin y Psicopedagoga, 17 (1), pp. 75-97Jaime, R.A., La orientacin educativa como tarea inseparable de la Extensin Universitaria (2011) Revista Cuadernos de Educacin y Desarrollo, 3 (28)Daz, T., La Extensin: Un proceso formativo de la Universidad. Su relacin con otros procesos (2001) Conferencia Magistral Del VI Taller Internacional de Extensin Universitaria, , Memorias, CubaGonzlez, G., (2002) Extensin Universitaria: Una Visin un Cambio Necesario, , Conferencia de la III Convencin Internacional de Educacin Superior, Memorias, CubaOliveira, N., The notorial dynamic analisis of an artificial satellite: A pedagogical experiment in space education (2008) Revista Brasileira de Ensino de Fsica, 30 (1), p. 1401Serra, R., Alfonso, I., Herrera, R., Ferreira, D., Muramatsu, M., Soga, D., (2013) La Fsica y El Trabajo Cientfico Estudiantil en la formación Del Ingeniero Biomdico, , enviado a LAJFE en proceso de arbitraje, eneroSerra, R., (2004) La Utilizacin Del Holograma Como Medio de Enseñanza y de Educacin Social en Cuba A Travs Del Vnculo Investigación-Docencia-Extensin Universitaria, , Tesis Doctoral CubaSerra, R., Moreno, A., Magalhes, D., Muramatsu, M., Lemus, J., Haciendo hologramas en la escuela y en la casa (2010) Revista Brasileira de Ensino de Fsica, 32 (3), p. 3502Zottola, D., Hernndez, A., Serra, R., Anaglifos en la Enseñanza de la ingeniera biomdica (2011) Proc. of v Latin American Congress on Biomedical Engineering, , Haban

    Positional impairment of gas exchange during diaphragm pacing alleviated by increasing amplitude settings in congenital central hypoventilation syndrome

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    Diaphragm pacing (DP) by phrenic nerve stimulation is a modality of chronic ventilatory support in individuals with congenital central hypoventilation syndrome (CCHS). We report a 9-year-old girl with CCHS who uses DP without tracheostomy during sleep. Her parents report hypoxemia and hypercapnia related to positional changes of the body during sleep requiring frequent adjustment of pacer settings. Overnight polysomnography was performed to titrate DP settings that showed adequate gas exchange in the supine position, but intermittent hypoxemia and hypercapnia were noted in the left decubitus position without obstructive sleep apnea occurring. Subsequently, the DP amplitude settings were increased during polysomnography, thereby identifying and treating positional hypoxemia and hypercapnia in various body positions. Our case emphasizes the importance of polysomnography in children with CCHS using DP to monitor for sleep-disordered breathing and titration of DP settings to achieve optimal oxygenation and ventilation with different body positions during sleep. © 2020 American Academy of Sleep Medicine. All rights reserved

    Morphometry And Histology Of Gonads From 13 Children With Dysgenetic Male Pseudohermaphroditism

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    Background. - Dysgenetic male pseudohermaphroditism (DMP) is a sexual differentiation disorder characterized by bilateral dysgenetic testes, persistent müllerian structures, and cryptorchidism in individuals with a 46,XY karyotype. However, the histologic criteria for the diagnosis of DMP are poorly established. Objective. - To determine gonadal histology in children with DMP. Patients and Methods. - Between 1996 and 1998, 13 patients with DMP were evaluated on our service. The clinical diagnosis of DMP was based on a 46,XY karyotype, sex ambiguity, high levels of follicle-stimulating hormone and low levels Of antimüllerian hormone, a decreased testosterone response to human chorionic gonadotropin stimulation without accumulation of testosterone precursors, and the presence of müllerian structures. Molecular sequencing the HMGbox region of the SRY gene did not reveal any mutations. Biopsies were performed for 22 of 26 gonads (patient age at the time of biopsy, 16 months to 10 years). Conventional microscopy was used to evaluate mean tubular diameter, tubular fertility index, and number of Sertoli cells per tubular profile. Results. - All 26 gonads were located outside of the labioscrotal folds. Their histologic features varied from only a reduction in tubular size to features of a streak gonad. Five of the 22 gonads grossly resembled a streak gonad. The mean tubular diameter was severely reduced (>30% reduction relative to the normal tubular diameter for the patient's age) in 4 gonads, markedly reduced (10%-30%) in 11 gonads, slightly reduced (<10%) in one gonad, and normal in one gonad. The tubular fertililty index, expressed as the percentage of tubular profiles containing germ cells, was severely reduced (<30% of normal values) in 9 gonads, markedly reduced (50%-30%) in 2 gonads, and normal in 6 gonads. The number of Sertoli cells per tubular profile was elevated in 16 gonads and normal in one gonad. Thin tubules surrounded by fibrous tissue were occasionally observed. Conclusion. - The histologic findings confirmed the clinical diagnosis of DMP in every patient in the present series. However, gonadal histology was variable, and careful morphometric evaluation may be necessary to establish the diagnosis.1255652656Robboy, S.J., Miller, T., Donahoe, P.K., Dysgenesis of testicular and streak gonads in the syndrome of mixed gonadal dysgenesis: Perspective derived from clinicopathologic analysis of twenty-one cases (1982) Hum Pathol, 13, pp. 700-716Troche, V., Hernandez, E., Neoplasia arising in dysgenetic gonads (1986) Obstet Gynecol Surv, 41, pp. 74-79Krasna, I.H., Lee, M.L., Smilow, P., Sciorra, L., Eierman, L., Risk of malignancy in bilateral streak gonads: The role of the Y chromosome (1992) J Pediatr Surg, 27, pp. 1376-1380Rohatgi, M., Gupta, D.K., Menon, P.S., Verma, I.C., Mathur, M., Mixed gonadal dysgenesis and dysgenetic male pseudohermaphroditism - A critical analysis (1992) Indian J Pediatr, 59, pp. 487-500Rey, R.A., Belville, C., Nhou-Fékété, C., Evaluation of gonadal function in 107 intersex patients by means of serum antimüllerian hormone measurement (1999) J Clin Endocrinol Metab, 84, pp. 627-631Stuchi-Perez, E.G., Lukas-Croisier, C., Castro, M., Evaluation of the tubular and interstitial functions of the testis in 46,XY patients with ambiguous genitalia (2000) J Pediatr Endocrinol Metab, 13, pp. 605-612Chang, H.J., Clark, R.D., Bachman, H., The phenotype of 45,X/46,XY mosaicism: An analysis of 92 prenatally diagnosed cases (1990) Am J Hum Genet, 46, pp. 156-167Rajfer, J., Walsh, P.C., Mixed gonadal dysgenesis: Dysgenetic male pseudoher-maphroditism (1981) The Intersex Child: Pediatric and Adolescent Endocrinology, pp. 103-115. , Josso N, ed. Basel, Switzerland: S. KargerBorer, J.G., Nitti, V.W., Glassberg, K.I., Mixed gonadal dysgenesis and dysgenetic male pseudohermaphroditism (1995) J Urol, 153, pp. 1267-1273Donahoe, P.K., Crawford, J.D., Hendren, W.H., Mixed gonadal dysgenesis: Pathogenesis and management (1979) J Pediatr Surg, 14, pp. 287-300Pelletier, J., Bruening, W., Kashtan, C.E., Germline mutations in the Wilms' tumor supressor gene are associated with abnormal urogenital development in Denys-Drash syndrome (1991) Cell, 67, pp. 437-1147Carré-Éusebe, D., Imbeaud, S., Harbison, M., New, M.I., Josso, N., Picard, J.Y., Variants of the anti-Müllerian hormone gene in a compound heterozygote with the persistent Müllerian duct syndrome and his family (1992) Hum Genet, 90, pp. 389-394Nistal, M., Paniagua, R., Non-neoplastic diseases of the testis (1996) Urologic Surgical Pathology, pp. 458-565. , Bostiwick DG, Eble JN, eds. St Louis, Mo: MosbyLennox, B., Ahmad, K.M., Mack, W.S., A method for determining the relative total length of the tubules in the testis (1970) J Pathol, 102, pp. 229-238Jimenez, R., Sanchez, A., Burgos, M., Dias De La Guardia, R.C., Puzzling out the genetics of mammalian sex determination (1996) Trends Genet, 12, pp. 164-166Müller, J., Skakkebaek, N.F., Quantification of germ cells and seminiferous tubules by stereological examination of testicles from 50 boys who suffered from sudden death (1983) Int J Androl, 6, pp. 143-156Cortes, D., Müller, J., Skakkebaek, N.E., Proliferation of Sertoli cells during development of the human testis assessed by stereological methods (1987) Int J Androl, 10, pp. 589-596Nistal, M., Abaurrea, M.A., Paniagua, R., Morphological and histometric study on the human Sertoli cell from birth to the onset of puberty (1982) J Anat, 14, pp. 351-363Van Niekerk, W.A., Retief, A.E., The gonads of human true hermaphrodites (1981) Hum Genet, 58, pp. 117-122Guerra Jr., G., De Mello, M.P., Assumpção, J.G., True hermaphrodites in the southeastern region of Brazil: A different cytogenetic and gonadal profile (1998) J Pediatr Endocrinol Metab, 11, pp. 519-524Quigley, C.A., De Bellis, A., Marschke, K.B., El-Awady, M.K., Wilson, E.M., French, F.S., Androgen receptor defects: Historical, clinical and molecular perspectives (1995) Endocr Rev, 16, pp. 271-32

    Dispersion de esporas de Thecaphora frezii hacia nuevas areas productivas

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    Resumen extendidoEl carbón del maní, causado por Thecaphora frezii, es el problema sanitario que mayor preocupación causa al sector manisero argentino. Las semillas utilizadas pueden venir contaminadas por teliosporas de T. frezii debido a el procesamiento de la industria, además pueden contener pequeñas lesiones de carbón que escapan de los procesos de selección. La importancia de conocer y cuantificar la carga de esporas presentes en semillas de maní es fundamental para evitar la dispersión del patógeno hacia nuevas áreas de producción, implementando estrategias de manejo. El objetivo del trabajo fue determinar el porcentaje de semillas afectadas por carbón, su severidad y la cantidad de esporas presentes en semillas utilizadas para la siembra en la campaña 2021/2022; cuantificar el inoculo inicial y final de suelo producto de la incidencia de carbón en dos lotes de maní de nuevas áreas productivas que nunca habian tenido maní (Vedía, Buenos Aires y Teodelina, Santa Fe).Centro de Investigaciones AgropecuariasFil: Pérez, I. A. Fundación Maní Argentina; ArgentinaFil: Paredes, Juan Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Fitopatología y Modelización Agrícola (UFyMA); ArgentinaFil: Paredes, Juan Andrés. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; ArgentinaFil: Mortigliengo, S. Morel Vulliez SA; ArgentinaFil: Monguillot, Joaquín Humberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Fitopatología y Modelización Agrícola (UFyMA); ArgentinaFil: Monguillot, Joaquín Humberto. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; ArgentinaFil: Rago, Alejandro Mario. Instituto Nacional de Tecnología Agropecuaria (INTA). Centro de Investigaciones Agropecuarias (CIAP); ArgentinaFil: Rago, Alejandro Mario. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; Argentin

    Comportamiento de cultivares de maní alto oleico frente a “Thecaphora Frezii” en distintas condiciones hídricas

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    El carbón del maní (Thecaphora frezii) es una de las enfermedades más importantes que presenta el cultivo. Desde el año 2012, su prevalencia es del 100% en la región manisera de Córdoba (Rago et al., 2017), y al ser una enfermedad poliética, los registros de incidencia son crecientes año tras año agravando la situación. Una de las causas del incremento en la incidencia de la enfermedad es la falta de implementación de medidas contundentes para mitigar la infección, reproducción y dispersión del patógeno. Actualmente, los principales cultivares utilizados son altamente susceptibles a esta enfermedad, lo que conduce a perdidas de rendimiento y calidad de grano. Adicionalmente, estudios previos indican que en condiciones de sequía la enfermedad aumenta considerablemente (Paredes et al., 2018). En este sentido y teniendo en cuenta el mejoramiento genético como herramienta para mitigar la enfermedad, se planteó como objetivo evaluar el comportamiento de diferentes cultivares comerciales tolerantes y susceptibles frente al carbón en distintas condiciones hídricas (riego y secano).Centro de Investigaciones AgropecuariasFil: Pérez, I.A. Fundación ArgenINTA. Delegación CIAP; ArgentinaFil: Paredes, Juan Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Fitopatología y Modelización Agrícola (UFyMA); ArgentinaFil: Paredes, Juan Andrés. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; ArgentinaFil: Brichi, L. Prodeman; ArgentinaFil: Monguillot, Joaquín Humberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Fitopatología y Modelización Agrícola (UFyMA); ArgentinaFil: Monguillot, Joaquín Humberto. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; ArgentinaFil: Rago, Alejandro Mario. Instituto Nacional de Tecnología Agropecuaria (INTA). Centro de Investigaciones Agropecuarias (CIAP); ArgentinaFil: Rago, Alejandro Mario. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; Argentin

    Solar fuel production by using PV/PEC junctions based on earth-abundant materials

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    One of the main problems of renewable energies is storage of the energy carrier. For long-term storage, solar fuels seem to be a good option. Direct solar water splitting could play an important role in the production of these solar fuels. One of the main challenges of this process is the charge separation and collection at the interfaces. The knowledge on photovoltaic (PV) junctions can be used to tackle this challenge. In this work, the use of doped layers to enhance the electric field in an a-SiC:H photocathode, and the use of thin-film silicon multijunction devices to achieve a stand-alone solar water splitting device are discussed. Using a p-i-n structure as a-SiC:H photocathode, a current density of 10mA/cm2 is achievable. The p-i-n structure proposed also indicates the suitability of traditional PV structures for solar water splitting. In addition, hybrid devices, including a silicon heterojunction PV device, are proposed. A combination of the a-SiC:H photocathode with a nc-Si:H/c-Si is demonstrated and potential STH efficiencies of 7.9% have been achieved. Furthermore, a purely PV approach such as a triple junction a-Si:H/nc-Si:H/nc-Si:H solar cell is demonstrated, with solar-to-hydrogen (STH) efficiencies of 9.8%

    Advances in ab-initio theory of Multiferroics. Materials and mechanisms: modelling and understanding

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    Within the broad class of multiferroics (compounds showing a coexistence of magnetism and ferroelectricity), we focus on the subclass of "improper electronic ferroelectrics", i.e. correlated materials where electronic degrees of freedom (such as spin, charge or orbital) drive ferroelectricity. In particular, in spin-induced ferroelectrics, there is not only a {\em coexistence} of the two intriguing magnetic and dipolar orders; rather, there is such an intimate link that one drives the other, suggesting a giant magnetoelectric coupling. Via first-principles approaches based on density functional theory, we review the microscopic mechanisms at the basis of multiferroicity in several compounds, ranging from transition metal oxides to organic multiferroics (MFs) to organic-inorganic hybrids (i.e. metal-organic frameworks, MOFs)Comment: 22 pages, 9 figure

    Investigation of the e+eωπ0π0π0γe^+e^- \to \omega \pi^0 \to \pi^0 \pi^0 \gamma reaction in the energy domain near the ϕ\phi-meson

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    The e+eωπ0π0π0γe^+e^- \to \omega \pi^0 \to \pi^0 \pi^0 \gamma process was investigated in the SND experiment at the VEPP-2M collider. A narrow energy interval near the ϕ\phi-meson was scanned. The observed cross-section reveals, at the level of three standard deviation, the interference effect caused by ϕπ0π0γ\phi \to \pi^0\pi^0\gamma decay. The cross-section parameters, as well as the real and imaginary parts of the ϕ\phi-meson related amplitude, were measured.Comment: 34 pages, 7 figures, LaTeX, uses FEYNMAN package. Erroneously reported C_{12} coefficient corrected (an error discovered in hep-ph/0603241). in the published version Nucl. Phys. B569(2000), 158 this coefficient is reported incorrectl

    Large enhancement of deuteron polarization with frequency modulated microwaves

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    We report a large enhancement of 1.7 in deuteron polarization up to values of 0.6 due to frequency modulation of the polarizing microwaves in a two liters polarized target using the method of dynamic nuclear polarization. This target was used during a deep inelastic polarized muon-deuteron scattering experiment at CERN. Measurements of the electron paramagnetic resonance absorption spectra show that frequency modulation gives rise to additional microwave absorption in the spectral wings. Although these results are not understood theoretically, they may provide a useful testing ground for the deeper understanding of dynamic nuclear polarization.Comment: 10 pages, including the figures coming in uuencoded compressed tar files in poltar.uu, which also brings cernart.sty and crna12.sty files neede

    Measurement of the p-pbar -> Wgamma + X cross section at sqrt(s) = 1.96 TeV and WWgamma anomalous coupling limits

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    The WWgamma triple gauge boson coupling parameters are studied using p-pbar -> l nu gamma + X (l = e,mu) events at sqrt(s) = 1.96 TeV. The data were collected with the DO detector from an integrated luminosity of 162 pb^{-1} delivered by the Fermilab Tevatron Collider. The cross section times branching fraction for p-pbar -> W(gamma) + X -> l nu gamma + X with E_T^{gamma} > 8 GeV and Delta R_{l gamma} > 0.7 is 14.8 +/- 1.6 (stat) +/- 1.0 (syst) +/- 1.0 (lum) pb. The one-dimensional 95% confidence level limits on anomalous couplings are -0.88 < Delta kappa_{gamma} < 0.96 and -0.20 < lambda_{gamma} < 0.20.Comment: Submitted to Phys. Rev. D Rapid Communication
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