Introducción: el quiste aracnoideo es una colección benigna de fluido similar en composición al l... more Introducción: el quiste aracnoideo es una colección benigna de fluido similar en composición al líquido cefalorraquídeo dentro de la aracnoides, circunscrita por tejido fibrovascular normal que comprime las leptomeninges que rodean el nervio óptico. Reporte: Se describe el caso de una paciente con quiste aracnoideo de la vaina del nervio óptico con un defecto campimétrico típico de glaucoma, pero con un disco óptico sin características de glaucoma, con el fin de resaltar la necesidad de estudiar con neuroimágenes estos casos y detectar este tipo de alteraciones. Conclusi´ón: El quiste aracnoideo de la vaina del nervio óptico es una entidad excepcional que generalmente tiene un comportamiento benigno, permaneciendo estable en el tiempo, aunque eventualmente puede producir una neuropatía óptica compresiva, afectando la agudeza o el campo visual por daño de la capa de fibras nerviosas. En el caso descrito, este daño se manifestó con un defecto de campo visual que simulaba neuropatía gl...
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Debido a que en la actualidad se trata de optimizar at maxima los calculos aprovechando las facil... more Debido a que en la actualidad se trata de optimizar at maxima los calculos aprovechando las facilidades que presta el computador, se ha desarrollado un software denominado AUTOMAT de procesamiento electranico en lenguaje de programacion Visual Basic que realiza calculos de los ensayos de laboratorio con exactitud y en forma agii El presente software sin lugar a duda vendrIa a constituir en una herramienta muy util para los diferentes trabajos que se reatizan en los laboratorios de las areas de Materiales y Geotecnia de la Unidad de Ingenieria Civil, Geologa y Minas (U.C.G)
Revista de la Asociación Colombiana de Dermatología y Cirugía Dermatológica, 2017
La mucormicosis es una micosis oportunista y poco frecuente, producida por hongos Zygomicetos del... more La mucormicosis es una micosis oportunista y poco frecuente, producida por hongos Zygomicetos del orden Mucorales, asociada con inmunosupresión y de curso agresivo y mortal. Puede dividirse en varios tipos, según el lugar de infección, en rinocerebral (por extensión desde la rinofaringe o por diseminación hematógena), cutánea (más habitualmente en pacientes con diabetes mellitus descompensada, leucemia o cáncer) y pulmonar, entre otras. Generalmente, se adquiere por vía respiratoria ya que las esporas de los hongos se encuentran en el ambiente, aunque en las formas cutáneas primarias, la infección se adquiere por solución de continuidad. El diagnóstico se confirma con un estudio completo de hongos (examen directo y cultivo para hongos en agar Sabouraud). El estudio anatomo-patológico, aunque permite visualizar perfectamente a los agentes fúngicos, por su demora, no es el método diagnóstico de elección. Una vez hecho el diagnóstico, se debe iniciar un tratamiento temprano, oportuno y...
Proceedings of the 13th International Web for All Conference, 2016
Access to high-quality braille materials for mathematical content is one of the most challenging ... more Access to high-quality braille materials for mathematical content is one of the most challenging obstacles faced by visuallyimpaired students. The need for visually-impaired students to communicate their work to sighted instructors often prevents them from participating in mainstream classrooms in STEM subjects. Backward translation from Nemeth Braille to print mathematics is a difficult and time-consuming process even for teachers of the visually impaired, who may not have an extensive understanding of the mathematical concepts underlying the notation. and in real-time with a visually-impaired Nemeth Braille user. This kind of instantaneous interaction has the potential to reduce, or even eliminate, many of the communication barriers that inhibit visually-impaired students from participating in mainstream math and science classrooms. CCS Concepts • Human-centered computing ➝ Accessibility ➝ Accessibility systems and tools • Information systems ➝ World Wide Web ➝ Web data description languages ➝ Markup languages.
The ethmoidal foramens are located on the medial wall of the orbit and are key reference points f... more The ethmoidal foramens are located on the medial wall of the orbit and are key reference points for intraoperative orientation. Detailed knowledge of the anatomy, bony landmarks and morphometric characteristics of the medial wall of the orbit is essential for various surgical procedures. The aim of this study was to determine the morphometric variations in the medial wall of the orbit and establish significant variations regarding age and gender. A total of 110 orbits were analyzed and subdivided by age (over or under 40 years) and gender. The distances of the medial wall of the orbit between the anterior lacrimal crest, the ethmoidal foramen, the optic canal and the interforamina were determined. Safe surgical areas were sought. Statistical tests were used to determine the differences between groups. In men, there is a safe surgical area proximal to the anterior and posterior ethmoidal foramen. In women, this area is in the posterior third of the medial wall of the orbit between the posterior ethmoidal foramen and the optic canal. Regarding variation according to age, the results of this study suggested that the anteroposterior diameter of the medial wall increases with age. This study showed that the anteroposterior total length of the medial orbit wall is similar between genders of similar age, increases with age, and has significant variations in the distances between the various structures that make up the medial orbit wall with regard to gender and age.
We consider a twisted version of the four-dimensional N = 4 supersymmetric Yang-Mills theory with... more We consider a twisted version of the four-dimensional N = 4 supersymmetric Yang-Mills theory with gauge groups SU(2) and SO(3), and bare masses for two of its chiral multiplets, thereby breaking N = 4 down to N = 2. Using the wall-crossing technique introduced by Moore and Witten within the u-plane approach to twisted topological field theories, we compute the partition function and all the topological correlation functions for the case of simply-connected spin fourmanifolds of simple type. By including 't Hooft fluxes, we analyse the properties of the resulting formulae under duality transformations. The partition function transforms in the same way as the one first presented by Vafa and Witten for another twist of the N = 4 supersymmetric theory in their strong coupling test of S-duality. Both partition functions coincide on K3. The topological correlation functions turn out to transform covariantly under duality, following a simple pattern which seems to be inherent in a general type of topological quantum field theories.
Mass perturbations of the twisted N = 4 supersymmetric gauge theory considered by Vafa and Witten... more Mass perturbations of the twisted N = 4 supersymmetric gauge theory considered by Vafa and Witten to test S-duality are studied for the case of Kähler four-manifolds. It is shown that the resulting mass-perturbed theory can be regarded as an equivariant extension associated to a U(1) symmetry of the twisted theory, which is only present for Kähler manifolds. In addition, it is shown that the partition function, the only topological invariant of the theory, remains invariant under the perturbation.
Coastal regions are vulnerable to storm surge and flooding due to tropical and extratropical stor... more Coastal regions are vulnerable to storm surge and flooding due to tropical and extratropical storms. It is necessary to build robust resiliency of the coastal communities to these hazards. The main objectives of operational surge and inundation forecast and coastal warning systems are to protect life and to sustain economic prosperity. The National Oceanic and Atmospheric Administration of the United States has initiated an integrated effort through pilot demonstration projects, and model-based ocean and coastal forecasting systems, to build improved operational warnings and forecasts capability for storm surge and inundation. This note describes the overall strategy and progress to date, with an emphasis on forecasting extratropical storm surge. Keywords Coastal flooding Á Warnings and forecasts Á Coastal modeling 1 Introduction Coastal regions around the world are often heavily populated, and their economic productivity and importance is significant. Over 50% of the population of the US resides in the coastal region. About 60% of the US gross domestic product is derived from these communities. Coastal regions are vulnerable to natural hazards such as surge and flooding
To compare the incidence of conjunctival infection with Chlamydia trachomatis in sexual partners ... more To compare the incidence of conjunctival infection with Chlamydia trachomatis in sexual partners of patients with newly diagnosed adult inclusion conjunctivitis (AIC) and a control group with healthy eyes. We also compare the observed signs and symptoms of conjunctival infection in patients with newly diagnosed AIC and their sexual partners. We performed a prospective comparative case-control study between patients with newly diagnosed AIC confirmed with direct fluorescent antibody (DFA) (n = 11), their sexual partners (n = 11), and a control group of healthy subjects (n = 11). Clinical history, physical examination, and a DFA test for C. trachomatis of a conjunctival scrapping from the tarsal conjunctiva were performed in all patients. A significantly higher frequency of positive DFA tests for C. trachomatis was observed in the sexual partner group (n = 8, 73 %) compared with the healthy control group (n = 2, 18.2 %) (P = 0.03). Ocular symptoms and signs were observed significantly more often in patients from the confirmed clinically active AIC group (n = 11, 100 %) than in their sexual partners (n = 2, 12.5 %). Sexual partners of patients with AIC are at greater risk of having an asymptomatic conjunctival infection with C. trachomatis than healthy subjects. Sexual partners might be considered a bacterial reservoir and a possible source for chlamydia reinfection. Not treating sexual partners might increase the probability of reinfection. More extended studies with a greater sample size should be done.
Objetivo: evaluar el efecto del láser Nd:Yag de doble frecuencia (532nm) subumbral (invisible) en... more Objetivo: evaluar el efecto del láser Nd:Yag de doble frecuencia (532nm) subumbral (invisible) en el tratamiento del edema macular diabético clínicamente significativo. Métodos: se trataron prospectívamente 84 ojos de 54 pacientes diabéticos con edema macular clínicamente significativo mediante fotocoagulación subumbral (invisible) con láser Nd:Yag de doble frecuencia. El seguimiento fue de doce meses. Se valoraron la evolución del edema macular, las repeticiones del tratamiento, la agudeza visual, los escotomas y las complicaciones maculares post-láser. Resultados: en general, el edema macular disminuyó o desapareció en 67.9% de los ojos en los primeros seis meses con una o dos sesiones de tratamiento y en 85.7% de los ojos después de una o cuatro sesiones de tratamiento al finalizar los 12 meses del seguimiento. La agudeza visual mejoró en 48.8% de los casos y en 34.5% se mantuvo estable. Ningún paciente refirió aparición de escotomas después del tratamiento ni presentó complicaciones propias del láser. Conclusiones: la fotocoagulación subumbral (invisible) con Nd:Yag láser de doble frecuencia, además de ser efectiva en la resolución del edema macular clínicamente significativo diabético, disminuye las complicaciones maculares propias del láser convencional. Palabras claves: edema macular clínicamente significativo diabético, edema macular difuso, fotocoagulación, láser, subumbral.
Introducción: el quiste aracnoideo es una colección benigna de fluido similar en composición al l... more Introducción: el quiste aracnoideo es una colección benigna de fluido similar en composición al líquido cefalorraquídeo dentro de la aracnoides, circunscrita por tejido fibrovascular normal que comprime las leptomeninges que rodean el nervio óptico. Reporte: Se describe el caso de una paciente con quiste aracnoideo de la vaina del nervio óptico con un defecto campimétrico típico de glaucoma, pero con un disco óptico sin características de glaucoma, con el fin de resaltar la necesidad de estudiar con neuroimágenes estos casos y detectar este tipo de alteraciones. Conclusi´ón: El quiste aracnoideo de la vaina del nervio óptico es una entidad excepcional que generalmente tiene un comportamiento benigno, permaneciendo estable en el tiempo, aunque eventualmente puede producir una neuropatía óptica compresiva, afectando la agudeza o el campo visual por daño de la capa de fibras nerviosas. En el caso descrito, este daño se manifestó con un defecto de campo visual que simulaba neuropatía gl...
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Debido a que en la actualidad se trata de optimizar at maxima los calculos aprovechando las facil... more Debido a que en la actualidad se trata de optimizar at maxima los calculos aprovechando las facilidades que presta el computador, se ha desarrollado un software denominado AUTOMAT de procesamiento electranico en lenguaje de programacion Visual Basic que realiza calculos de los ensayos de laboratorio con exactitud y en forma agii El presente software sin lugar a duda vendrIa a constituir en una herramienta muy util para los diferentes trabajos que se reatizan en los laboratorios de las areas de Materiales y Geotecnia de la Unidad de Ingenieria Civil, Geologa y Minas (U.C.G)
Revista de la Asociación Colombiana de Dermatología y Cirugía Dermatológica, 2017
La mucormicosis es una micosis oportunista y poco frecuente, producida por hongos Zygomicetos del... more La mucormicosis es una micosis oportunista y poco frecuente, producida por hongos Zygomicetos del orden Mucorales, asociada con inmunosupresión y de curso agresivo y mortal. Puede dividirse en varios tipos, según el lugar de infección, en rinocerebral (por extensión desde la rinofaringe o por diseminación hematógena), cutánea (más habitualmente en pacientes con diabetes mellitus descompensada, leucemia o cáncer) y pulmonar, entre otras. Generalmente, se adquiere por vía respiratoria ya que las esporas de los hongos se encuentran en el ambiente, aunque en las formas cutáneas primarias, la infección se adquiere por solución de continuidad. El diagnóstico se confirma con un estudio completo de hongos (examen directo y cultivo para hongos en agar Sabouraud). El estudio anatomo-patológico, aunque permite visualizar perfectamente a los agentes fúngicos, por su demora, no es el método diagnóstico de elección. Una vez hecho el diagnóstico, se debe iniciar un tratamiento temprano, oportuno y...
Proceedings of the 13th International Web for All Conference, 2016
Access to high-quality braille materials for mathematical content is one of the most challenging ... more Access to high-quality braille materials for mathematical content is one of the most challenging obstacles faced by visuallyimpaired students. The need for visually-impaired students to communicate their work to sighted instructors often prevents them from participating in mainstream classrooms in STEM subjects. Backward translation from Nemeth Braille to print mathematics is a difficult and time-consuming process even for teachers of the visually impaired, who may not have an extensive understanding of the mathematical concepts underlying the notation. and in real-time with a visually-impaired Nemeth Braille user. This kind of instantaneous interaction has the potential to reduce, or even eliminate, many of the communication barriers that inhibit visually-impaired students from participating in mainstream math and science classrooms. CCS Concepts • Human-centered computing ➝ Accessibility ➝ Accessibility systems and tools • Information systems ➝ World Wide Web ➝ Web data description languages ➝ Markup languages.
The ethmoidal foramens are located on the medial wall of the orbit and are key reference points f... more The ethmoidal foramens are located on the medial wall of the orbit and are key reference points for intraoperative orientation. Detailed knowledge of the anatomy, bony landmarks and morphometric characteristics of the medial wall of the orbit is essential for various surgical procedures. The aim of this study was to determine the morphometric variations in the medial wall of the orbit and establish significant variations regarding age and gender. A total of 110 orbits were analyzed and subdivided by age (over or under 40 years) and gender. The distances of the medial wall of the orbit between the anterior lacrimal crest, the ethmoidal foramen, the optic canal and the interforamina were determined. Safe surgical areas were sought. Statistical tests were used to determine the differences between groups. In men, there is a safe surgical area proximal to the anterior and posterior ethmoidal foramen. In women, this area is in the posterior third of the medial wall of the orbit between the posterior ethmoidal foramen and the optic canal. Regarding variation according to age, the results of this study suggested that the anteroposterior diameter of the medial wall increases with age. This study showed that the anteroposterior total length of the medial orbit wall is similar between genders of similar age, increases with age, and has significant variations in the distances between the various structures that make up the medial orbit wall with regard to gender and age.
We consider a twisted version of the four-dimensional N = 4 supersymmetric Yang-Mills theory with... more We consider a twisted version of the four-dimensional N = 4 supersymmetric Yang-Mills theory with gauge groups SU(2) and SO(3), and bare masses for two of its chiral multiplets, thereby breaking N = 4 down to N = 2. Using the wall-crossing technique introduced by Moore and Witten within the u-plane approach to twisted topological field theories, we compute the partition function and all the topological correlation functions for the case of simply-connected spin fourmanifolds of simple type. By including 't Hooft fluxes, we analyse the properties of the resulting formulae under duality transformations. The partition function transforms in the same way as the one first presented by Vafa and Witten for another twist of the N = 4 supersymmetric theory in their strong coupling test of S-duality. Both partition functions coincide on K3. The topological correlation functions turn out to transform covariantly under duality, following a simple pattern which seems to be inherent in a general type of topological quantum field theories.
Mass perturbations of the twisted N = 4 supersymmetric gauge theory considered by Vafa and Witten... more Mass perturbations of the twisted N = 4 supersymmetric gauge theory considered by Vafa and Witten to test S-duality are studied for the case of Kähler four-manifolds. It is shown that the resulting mass-perturbed theory can be regarded as an equivariant extension associated to a U(1) symmetry of the twisted theory, which is only present for Kähler manifolds. In addition, it is shown that the partition function, the only topological invariant of the theory, remains invariant under the perturbation.
Coastal regions are vulnerable to storm surge and flooding due to tropical and extratropical stor... more Coastal regions are vulnerable to storm surge and flooding due to tropical and extratropical storms. It is necessary to build robust resiliency of the coastal communities to these hazards. The main objectives of operational surge and inundation forecast and coastal warning systems are to protect life and to sustain economic prosperity. The National Oceanic and Atmospheric Administration of the United States has initiated an integrated effort through pilot demonstration projects, and model-based ocean and coastal forecasting systems, to build improved operational warnings and forecasts capability for storm surge and inundation. This note describes the overall strategy and progress to date, with an emphasis on forecasting extratropical storm surge. Keywords Coastal flooding Á Warnings and forecasts Á Coastal modeling 1 Introduction Coastal regions around the world are often heavily populated, and their economic productivity and importance is significant. Over 50% of the population of the US resides in the coastal region. About 60% of the US gross domestic product is derived from these communities. Coastal regions are vulnerable to natural hazards such as surge and flooding
To compare the incidence of conjunctival infection with Chlamydia trachomatis in sexual partners ... more To compare the incidence of conjunctival infection with Chlamydia trachomatis in sexual partners of patients with newly diagnosed adult inclusion conjunctivitis (AIC) and a control group with healthy eyes. We also compare the observed signs and symptoms of conjunctival infection in patients with newly diagnosed AIC and their sexual partners. We performed a prospective comparative case-control study between patients with newly diagnosed AIC confirmed with direct fluorescent antibody (DFA) (n = 11), their sexual partners (n = 11), and a control group of healthy subjects (n = 11). Clinical history, physical examination, and a DFA test for C. trachomatis of a conjunctival scrapping from the tarsal conjunctiva were performed in all patients. A significantly higher frequency of positive DFA tests for C. trachomatis was observed in the sexual partner group (n = 8, 73 %) compared with the healthy control group (n = 2, 18.2 %) (P = 0.03). Ocular symptoms and signs were observed significantly more often in patients from the confirmed clinically active AIC group (n = 11, 100 %) than in their sexual partners (n = 2, 12.5 %). Sexual partners of patients with AIC are at greater risk of having an asymptomatic conjunctival infection with C. trachomatis than healthy subjects. Sexual partners might be considered a bacterial reservoir and a possible source for chlamydia reinfection. Not treating sexual partners might increase the probability of reinfection. More extended studies with a greater sample size should be done.
Objetivo: evaluar el efecto del láser Nd:Yag de doble frecuencia (532nm) subumbral (invisible) en... more Objetivo: evaluar el efecto del láser Nd:Yag de doble frecuencia (532nm) subumbral (invisible) en el tratamiento del edema macular diabético clínicamente significativo. Métodos: se trataron prospectívamente 84 ojos de 54 pacientes diabéticos con edema macular clínicamente significativo mediante fotocoagulación subumbral (invisible) con láser Nd:Yag de doble frecuencia. El seguimiento fue de doce meses. Se valoraron la evolución del edema macular, las repeticiones del tratamiento, la agudeza visual, los escotomas y las complicaciones maculares post-láser. Resultados: en general, el edema macular disminuyó o desapareció en 67.9% de los ojos en los primeros seis meses con una o dos sesiones de tratamiento y en 85.7% de los ojos después de una o cuatro sesiones de tratamiento al finalizar los 12 meses del seguimiento. La agudeza visual mejoró en 48.8% de los casos y en 34.5% se mantuvo estable. Ningún paciente refirió aparición de escotomas después del tratamiento ni presentó complicaciones propias del láser. Conclusiones: la fotocoagulación subumbral (invisible) con Nd:Yag láser de doble frecuencia, además de ser efectiva en la resolución del edema macular clínicamente significativo diabético, disminuye las complicaciones maculares propias del láser convencional. Palabras claves: edema macular clínicamente significativo diabético, edema macular difuso, fotocoagulación, láser, subumbral.
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