A two-dimensional cellular complex is a partition of a surface into a finite number of elements—f... more A two-dimensional cellular complex is a partition of a surface into a finite number of elements—faces (open disks), edges (open arcs), and vertices (points). The topology of a cellular complex is the abstract incidence and adjacency relations among its elements. Here we describe a program that, given only the topology of a cellular complex, computes a geometric realization of the same—that is, a specific partition of a specific surface in three-space—guided by various aesthetic and presentational criteria.
Abstract The Socio Bosque program is a national conservation agreement scheme of the government o... more Abstract The Socio Bosque program is a national conservation agreement scheme of the government of Ecuador. Socio Bosque consists of the transfer of a direct monetary incentive per hectare of native forest and other native ecosystems to individual landowners and ...
Circular migration and injection drug use increase the risk of HIV transmission in sending commun... more Circular migration and injection drug use increase the risk of HIV transmission in sending communities. We describe female sex workers who are injection drug users’ (FSW-IDUs) circular migration and drug use behaviors. Between 2008-2010, 258 migrant FSW-IDUs residing in Tijuana and Ciudad Juarez, Mexico responded to questionnaires. 24% of FSW-IDUs were circular migrants. HIV prevalence was 3.2% in circular migrants and 6.1% in non-circular migrants; 50% of circular and 75% of non-circular migrants were unaware of their HIV infection. Among circular migrants, 44% (n = 27) consumed illicit drugs in their birthplace; 74% of these (n = 20) injected drugs and one-half of injectors shared injection equipment in their birthplace. Women reporting active social relationships were significantly more likely to return home. Circular migrant FSW-IDUs exhibit multiple HIV risks and opportunities for bridging populations. Regular HIV testing and treatment and access to substance use services is critical for FSW-IDUs and their sexual/drug-using contacts.
A three-dimensional map is a partition of a 3D manifold into topological polyhedra. We consider t... more A three-dimensional map is a partition of a 3D manifold into topological polyhedra. We consider the problem of visualizing the topology of a three-dimensional map given only its combinatorial description. Our solution starts by automatically constructing a “nice” geometric realization of the map in Rm, for some m⩾4. The geometric realization is chosen by optimizing certain aesthetic criteria, measured by
The CMS Level-1 trigger was used to select cosmic ray muons and LHC beam events during data-takin... more The CMS Level-1 trigger was used to select cosmic ray muons and LHC beam events during data-taking runs in 2008, and to estimate the level of detector noise. This paper describes the trigger components used, the algorithms that were executed, and the trigger ...
La investigación aporta un modelo de la dinámica del proceso de diseño didáctico del software edu... more La investigación aporta un modelo de la dinámica del proceso de diseño didáctico del software educativo para la formación de profesionales en el contexto de la Educación Superior. El modelo revela los eslabones (etapas), dimensiones, configuraciones y estructuras de relaciones que conforman la dinámica del proceso de diseño didáctico del software educativo. Además entrega un procedimiento del modelo para implementar
Recent studies considered that an increase in sympathetic activity (SA) may be responsible for le... more Recent studies considered that an increase in sympathetic activity (SA) may be responsible for left ventricular hypertrophy (LVH). Before and after renal transplantation (RT), we evaluated changes on left ventricular mass (LVM) and SA in 40 end-stage renal disease patients between 8 and 35 years old. Hypertension (95.0% vs. 71.0%; p=0.005), use of combined antihypertensive drugs (57.5% vs. 30.0%; p=0.01), and LVH (77.5% vs. 52.5%; p=0.01) significantly decreased after RT whereas low-to-high frequency ratio (LF/HF), which represents SA, increased (3.1 vs. 5.3; p=0.0001). However, LVM regressors (with decrease on LVM index more than 20%) showed a trend of lower change on LF/HF ratio (1.6 vs. 2.4; p= 0.09) than nonregressors. Living-donor graft, baseline LVM, use of antihypertensive drugs, lower change on LF/HF ratio, and lower systolic blood pressure levels were associated with LVM regression in the simple correlation analysis. However, in the logistic regression analysis, only baseline LVM and donor type remained in the model (R2=0.35; p=0.0003). Thus, LVH decreased after RT and was related to baseline LVM and living-donor type. However, it is possible that the higher persistence of LVH after RT could be explained at least in part by increase in heart sympathetic activity and use of immunosuppressors.
Thermal and microwave reactions between [PcSnIVCl2] (1) and the potassium salts of eight fatty ac... more Thermal and microwave reactions between [PcSnIVCl2] (1) and the potassium salts of eight fatty acids (2 a–h) led to cis-[(RCO2)2SnIVPc] compounds (3 a–h) in yields ranging from 54 to 90 %. Compounds 3 a–h were fully characterized by elemental analysis, spectroscopy (IR, UV/Vis, multinuclear NMR), and seven X-ray diffraction structures, whereby two different allotropes were observed in two cases. The two carboxylates in 3 have a cis anisobidentate binding mode, octacoordination of the tin atoms with square-antiprismatic geometry, and π-electron-rich nanocap shapes. On account of the latter characteristics, 3 a–h compounds have anticorrosion properties. LPR and Tafel electrochemical methods were used to characterize the behavior of these derivatives in naturally aerated sour brine, which is a common environment in petroleum production and refinery operations. The measurement of the corrosion rate of carbon steel AISI 1018 in the presence of 3 a–h (500 ppm) gave efficiencies of 61–87 % for the inhibitor performance. Of the different derivatives examined, compounds 3 e and 3 h were the most effective corrosion inhibitor prototypes.
We report some optical and electrical properties of CdS thin films fabricated by chemical-bath de... more We report some optical and electrical properties of CdS thin films fabricated by chemical-bath deposition. We investigated transmission, infrared, ultraviolet, and photoluminescence spectra, and did scanning electron microscopy, x-ray diffraction, and resistivity measurements before and after thermal annealing in a S2 atmosphere at different temperatures. A minimum bandgap and resistivity together with good definition in ultraviolet and infrared spectra at annealing temperature of 250 C support the existence of a predominant cubic phase for that annealing condition.
A two-dimensional cellular complex is a partition of a surface into a finite number of elements—f... more A two-dimensional cellular complex is a partition of a surface into a finite number of elements—faces (open disks), edges (open arcs), and vertices (points). The topology of a cellular complex is the abstract incidence and adjacency relations among its elements. Here we describe a program that, given only the topology of a cellular complex, computes a geometric realization of the same—that is, a specific partition of a specific surface in three-space—guided by various aesthetic and presentational criteria.
Abstract The Socio Bosque program is a national conservation agreement scheme of the government o... more Abstract The Socio Bosque program is a national conservation agreement scheme of the government of Ecuador. Socio Bosque consists of the transfer of a direct monetary incentive per hectare of native forest and other native ecosystems to individual landowners and ...
Circular migration and injection drug use increase the risk of HIV transmission in sending commun... more Circular migration and injection drug use increase the risk of HIV transmission in sending communities. We describe female sex workers who are injection drug users’ (FSW-IDUs) circular migration and drug use behaviors. Between 2008-2010, 258 migrant FSW-IDUs residing in Tijuana and Ciudad Juarez, Mexico responded to questionnaires. 24% of FSW-IDUs were circular migrants. HIV prevalence was 3.2% in circular migrants and 6.1% in non-circular migrants; 50% of circular and 75% of non-circular migrants were unaware of their HIV infection. Among circular migrants, 44% (n = 27) consumed illicit drugs in their birthplace; 74% of these (n = 20) injected drugs and one-half of injectors shared injection equipment in their birthplace. Women reporting active social relationships were significantly more likely to return home. Circular migrant FSW-IDUs exhibit multiple HIV risks and opportunities for bridging populations. Regular HIV testing and treatment and access to substance use services is critical for FSW-IDUs and their sexual/drug-using contacts.
A three-dimensional map is a partition of a 3D manifold into topological polyhedra. We consider t... more A three-dimensional map is a partition of a 3D manifold into topological polyhedra. We consider the problem of visualizing the topology of a three-dimensional map given only its combinatorial description. Our solution starts by automatically constructing a “nice” geometric realization of the map in Rm, for some m⩾4. The geometric realization is chosen by optimizing certain aesthetic criteria, measured by
The CMS Level-1 trigger was used to select cosmic ray muons and LHC beam events during data-takin... more The CMS Level-1 trigger was used to select cosmic ray muons and LHC beam events during data-taking runs in 2008, and to estimate the level of detector noise. This paper describes the trigger components used, the algorithms that were executed, and the trigger ...
La investigación aporta un modelo de la dinámica del proceso de diseño didáctico del software edu... more La investigación aporta un modelo de la dinámica del proceso de diseño didáctico del software educativo para la formación de profesionales en el contexto de la Educación Superior. El modelo revela los eslabones (etapas), dimensiones, configuraciones y estructuras de relaciones que conforman la dinámica del proceso de diseño didáctico del software educativo. Además entrega un procedimiento del modelo para implementar
Recent studies considered that an increase in sympathetic activity (SA) may be responsible for le... more Recent studies considered that an increase in sympathetic activity (SA) may be responsible for left ventricular hypertrophy (LVH). Before and after renal transplantation (RT), we evaluated changes on left ventricular mass (LVM) and SA in 40 end-stage renal disease patients between 8 and 35 years old. Hypertension (95.0% vs. 71.0%; p=0.005), use of combined antihypertensive drugs (57.5% vs. 30.0%; p=0.01), and LVH (77.5% vs. 52.5%; p=0.01) significantly decreased after RT whereas low-to-high frequency ratio (LF/HF), which represents SA, increased (3.1 vs. 5.3; p=0.0001). However, LVM regressors (with decrease on LVM index more than 20%) showed a trend of lower change on LF/HF ratio (1.6 vs. 2.4; p= 0.09) than nonregressors. Living-donor graft, baseline LVM, use of antihypertensive drugs, lower change on LF/HF ratio, and lower systolic blood pressure levels were associated with LVM regression in the simple correlation analysis. However, in the logistic regression analysis, only baseline LVM and donor type remained in the model (R2=0.35; p=0.0003). Thus, LVH decreased after RT and was related to baseline LVM and living-donor type. However, it is possible that the higher persistence of LVH after RT could be explained at least in part by increase in heart sympathetic activity and use of immunosuppressors.
Thermal and microwave reactions between [PcSnIVCl2] (1) and the potassium salts of eight fatty ac... more Thermal and microwave reactions between [PcSnIVCl2] (1) and the potassium salts of eight fatty acids (2 a–h) led to cis-[(RCO2)2SnIVPc] compounds (3 a–h) in yields ranging from 54 to 90 %. Compounds 3 a–h were fully characterized by elemental analysis, spectroscopy (IR, UV/Vis, multinuclear NMR), and seven X-ray diffraction structures, whereby two different allotropes were observed in two cases. The two carboxylates in 3 have a cis anisobidentate binding mode, octacoordination of the tin atoms with square-antiprismatic geometry, and π-electron-rich nanocap shapes. On account of the latter characteristics, 3 a–h compounds have anticorrosion properties. LPR and Tafel electrochemical methods were used to characterize the behavior of these derivatives in naturally aerated sour brine, which is a common environment in petroleum production and refinery operations. The measurement of the corrosion rate of carbon steel AISI 1018 in the presence of 3 a–h (500 ppm) gave efficiencies of 61–87 % for the inhibitor performance. Of the different derivatives examined, compounds 3 e and 3 h were the most effective corrosion inhibitor prototypes.
We report some optical and electrical properties of CdS thin films fabricated by chemical-bath de... more We report some optical and electrical properties of CdS thin films fabricated by chemical-bath deposition. We investigated transmission, infrared, ultraviolet, and photoluminescence spectra, and did scanning electron microscopy, x-ray diffraction, and resistivity measurements before and after thermal annealing in a S2 atmosphere at different temperatures. A minimum bandgap and resistivity together with good definition in ultraviolet and infrared spectra at annealing temperature of 250 C support the existence of a predominant cubic phase for that annealing condition.
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