We study some problems related to the derivative associated to the generalized Tanaka-Webster con... more We study some problems related to the derivative associated to the generalized Tanaka-Webster connection acting on the shape operator and some Jacobi operators of a real hypersurface in complex two-plane Grassmannians.
The Bulletin of the Malaysian Mathematical Society Series 2
We prove the non-existence of Hopf Real hypersurfaces in complex two-plane Grassmannians whose sh... more We prove the non-existence of Hopf Real hypersurfaces in complex two-plane Grassmannians whose shape operator is of Codazzi type with respect to the generalized Tanaka-Webster connection.
The genetic structure of 4 Colombian Creole cattle breeds, namely, Costeno con Cuernos, Blanco Or... more The genetic structure of 4 Colombian Creole cattle breeds, namely, Costeno con Cuernos, Blanco Orejinegro (BON), Romosinuano (ROMO), and Sanmartinero (SM), was studied with an analysis of the available pedigree data. The comparison between the effective number of founders (fe) and the effective number of ancestors (fa) revealed a decrease in the ge- netic variation that was rather important for
A treadmill for studying gas exchange in small mammals during exercise is presented. The system c... more A treadmill for studying gas exchange in small mammals during exercise is presented. The system consists of a motor-driven running mat enclosed in a gastight chamber that receives a measured flow of air from a compressed air cylinder. The gas flow and temperature, pressure and instantaneous gas composition of the chamber (oxygen, carbon dioxide and water) are measured continuously and the data are computed to include the effects on chamber atmosphere of the rat activity, either running or at rest. The system is completed with a shock delivery grid that stimulates the rat to run. The calculations are based on the changes in the composition of the gas in the chamber (constantly stirred by a small electric fan) induced by the rat instead of relying on the alterations induced in the outflowing gas. The consumption of oxygen, and production of carbon dioxide and water by the rat are computed in real time, giving a very fast response to physiological change induced by exercise. The chamber is custom-made from an aluminium block and a plexiglass lid; all other components are available commercially. The system, as described, allows for a detailed analysis of respiratory gas (and water) exchange by rats under varying exercise conditions, there is practically no time lag between changes in respiratory gases and the detection of these changes, and the buffering effect of the chamber size is practically eliminated because of the calculation approach used.
We classify real hypersurfaces of complex projective space CPm, m⩾3, with D-recurrent structure J... more We classify real hypersurfaces of complex projective space CPm, m⩾3, with D-recurrent structure Jacobi operator and apply this result to prove the non-existence of such hypersurfaces with recurrent structure Jacobi operator.
Bulletin of The Belgian Mathematical Society-simon Stevin, 2006
We prove the non existence of real hypersurfaces in complex projective space whose structure Jaco... more We prove the non existence of real hypersurfaces in complex projective space whose structure Jacobi operator is parallel in any direction of the maximal holomorphic distribution.
Summary The cassava starch presents a little variation in its quality. Although induced mutations... more Summary The cassava starch presents a little variation in its quality. Although induced mutations are a source of inherited variation for desirable traits, phenotypic expression of mutants is currently difficult to detect due to its heterozygous condition. The objective of this work was to produce M2 populations in order to increase the homozygous level of traits related to starch quality
The HarvestPlus initiative is supporting several breeding projects to increase carotenoids conten... more The HarvestPlus initiative is supporting several breeding projects to increase carotenoids content in cassava roots. The correct and reliable quantification of carotenoids content is critical for an efficient breeding process. This includes a proper sampling procedure (described in a different study in this meeting) and a clear understanding of the effect of age of the plant on carotenoids content. Our
General Circulation Models (GCMs) have proven to be an effective tool to simulate many aspects of... more General Circulation Models (GCMs) have proven to be an effective tool to simulate many aspects of large-scale and global climate. However, their applicability to climate impact studies is limited by their capabilities to resolve regional scale situations. In this sense, dynamical downscaling techniques are an appropriate alternative to estimate high resolution regional climatologies. In this work, the Weather Research and
Remote Sensing of Clouds and the Atmosphere XII, 2007
In this work a threshold technique for cloud detection and classification is applied to 9 years N... more In this work a threshold technique for cloud detection and classification is applied to 9 years NOAA-AVHRR imagery in order to obtain a cloud climatology of the Canary Islands region (Northeast Atlantic Ocean). Once the clouds are classified, a retrieval method is used to estimate cloud macro- and micro-physical parameters, such as, effective particle size, optical thickness and top temperature.
ABSTRACT In this paper, we give non-existence theorems for Hopf hypersurfaces in complex two-plan... more ABSTRACT In this paper, we give non-existence theorems for Hopf hypersurfaces in complex two-plane Grassmannians $G_2(\mathbb{C }^{m+2})$ with $\mathfrak D $ -parallel normal Jacobi operator ${\bar{R}}_N$ and $\mathfrak D $ -parallel structure Jacobi operator $R_{\xi }$ if the distribution $\mathfrak D $ or $\mathfrak D ^{\bot }$ component of the Reeb vector field is invariant by the shape operator, respectively.
The aim of this work is to describe a new arthroscopic technique for the treatment of femoroaceta... more The aim of this work is to describe a new arthroscopic technique for the treatment of femoroacetabular impingement that allows a complete articular joint view with maximum protection of the capsuloligamentous complex. This arthroscopic technique avoids injury to the capsuloligamentous complex, preventing the risk of postoperative instability. The diagnosis of femoroacetabular impingement was based on clinical and radiographic grounds. An alpha angle greater than 50° was considered pathologic. In this technique, the use of intra-articular devices (retractors) allows us to separate the capsular tissue from the femoral head-neck junction and mobilize the capsule, achieving an adequate joint view without performing a capsulotomy and, consequently, avoiding the complications of capsular damage.
Background and aim. Hepatocellular carcinoma (HCC) is the most common primary liver cancer diagno... more Background and aim. Hepatocellular carcinoma (HCC) is the most common primary liver cancer diagnosed worldwide. Deregulation of Wnt/beta-catenin pathway has been associated with the development of HCC in a substantial number of cases in Europe and far less in Asia. Nothing is known about this pathway in HCC cases from South America. This study aimed to investigate the frequency of mutations in beta-catenin gene (CTNNB1) and the subcellular localization of beta-catenin in HCC cases from Colombia. Material and methods. We determine by direct sequencing the frequency of mutations in exon 3 of CTNNB1 gene and by immunohistochemistry the subcellular localization of beta-catenin in 54 samples of HCC obtained from three pathology units in Bogota and Medellin cities. Results. Only three HCC cases (5.6%) were found mutated at residues (G34E, S45P, P44S, T41I) important for phosphorylation and ubiquitination of beta-catenin protein. Strikingly, nuclear or cytoplasmic accumulation of beta-cate...
This work addresses the automatic generation of conceptual models for XML-oriented databases, whi... more This work addresses the automatic generation of conceptual models for XML-oriented databases, which in many cases have little or no support for schemata. Our techniques are based on both an incremental clustering algorithm, which groups together the incoming XML documents according to their structural similarities, and a schema inference method, which maintains dynamically the schema of each detected document cluster. Our proposal takes into consideration the schema evolution. For this purpose, we have adapted the Toodor ...
We study some problems related to the derivative associated to the generalized Tanaka-Webster con... more We study some problems related to the derivative associated to the generalized Tanaka-Webster connection acting on the shape operator and some Jacobi operators of a real hypersurface in complex two-plane Grassmannians.
The Bulletin of the Malaysian Mathematical Society Series 2
We prove the non-existence of Hopf Real hypersurfaces in complex two-plane Grassmannians whose sh... more We prove the non-existence of Hopf Real hypersurfaces in complex two-plane Grassmannians whose shape operator is of Codazzi type with respect to the generalized Tanaka-Webster connection.
The genetic structure of 4 Colombian Creole cattle breeds, namely, Costeno con Cuernos, Blanco Or... more The genetic structure of 4 Colombian Creole cattle breeds, namely, Costeno con Cuernos, Blanco Orejinegro (BON), Romosinuano (ROMO), and Sanmartinero (SM), was studied with an analysis of the available pedigree data. The comparison between the effective number of founders (fe) and the effective number of ancestors (fa) revealed a decrease in the ge- netic variation that was rather important for
A treadmill for studying gas exchange in small mammals during exercise is presented. The system c... more A treadmill for studying gas exchange in small mammals during exercise is presented. The system consists of a motor-driven running mat enclosed in a gastight chamber that receives a measured flow of air from a compressed air cylinder. The gas flow and temperature, pressure and instantaneous gas composition of the chamber (oxygen, carbon dioxide and water) are measured continuously and the data are computed to include the effects on chamber atmosphere of the rat activity, either running or at rest. The system is completed with a shock delivery grid that stimulates the rat to run. The calculations are based on the changes in the composition of the gas in the chamber (constantly stirred by a small electric fan) induced by the rat instead of relying on the alterations induced in the outflowing gas. The consumption of oxygen, and production of carbon dioxide and water by the rat are computed in real time, giving a very fast response to physiological change induced by exercise. The chamber is custom-made from an aluminium block and a plexiglass lid; all other components are available commercially. The system, as described, allows for a detailed analysis of respiratory gas (and water) exchange by rats under varying exercise conditions, there is practically no time lag between changes in respiratory gases and the detection of these changes, and the buffering effect of the chamber size is practically eliminated because of the calculation approach used.
We classify real hypersurfaces of complex projective space CPm, m⩾3, with D-recurrent structure J... more We classify real hypersurfaces of complex projective space CPm, m⩾3, with D-recurrent structure Jacobi operator and apply this result to prove the non-existence of such hypersurfaces with recurrent structure Jacobi operator.
Bulletin of The Belgian Mathematical Society-simon Stevin, 2006
We prove the non existence of real hypersurfaces in complex projective space whose structure Jaco... more We prove the non existence of real hypersurfaces in complex projective space whose structure Jacobi operator is parallel in any direction of the maximal holomorphic distribution.
Summary The cassava starch presents a little variation in its quality. Although induced mutations... more Summary The cassava starch presents a little variation in its quality. Although induced mutations are a source of inherited variation for desirable traits, phenotypic expression of mutants is currently difficult to detect due to its heterozygous condition. The objective of this work was to produce M2 populations in order to increase the homozygous level of traits related to starch quality
The HarvestPlus initiative is supporting several breeding projects to increase carotenoids conten... more The HarvestPlus initiative is supporting several breeding projects to increase carotenoids content in cassava roots. The correct and reliable quantification of carotenoids content is critical for an efficient breeding process. This includes a proper sampling procedure (described in a different study in this meeting) and a clear understanding of the effect of age of the plant on carotenoids content. Our
General Circulation Models (GCMs) have proven to be an effective tool to simulate many aspects of... more General Circulation Models (GCMs) have proven to be an effective tool to simulate many aspects of large-scale and global climate. However, their applicability to climate impact studies is limited by their capabilities to resolve regional scale situations. In this sense, dynamical downscaling techniques are an appropriate alternative to estimate high resolution regional climatologies. In this work, the Weather Research and
Remote Sensing of Clouds and the Atmosphere XII, 2007
In this work a threshold technique for cloud detection and classification is applied to 9 years N... more In this work a threshold technique for cloud detection and classification is applied to 9 years NOAA-AVHRR imagery in order to obtain a cloud climatology of the Canary Islands region (Northeast Atlantic Ocean). Once the clouds are classified, a retrieval method is used to estimate cloud macro- and micro-physical parameters, such as, effective particle size, optical thickness and top temperature.
ABSTRACT In this paper, we give non-existence theorems for Hopf hypersurfaces in complex two-plan... more ABSTRACT In this paper, we give non-existence theorems for Hopf hypersurfaces in complex two-plane Grassmannians $G_2(\mathbb{C }^{m+2})$ with $\mathfrak D $ -parallel normal Jacobi operator ${\bar{R}}_N$ and $\mathfrak D $ -parallel structure Jacobi operator $R_{\xi }$ if the distribution $\mathfrak D $ or $\mathfrak D ^{\bot }$ component of the Reeb vector field is invariant by the shape operator, respectively.
The aim of this work is to describe a new arthroscopic technique for the treatment of femoroaceta... more The aim of this work is to describe a new arthroscopic technique for the treatment of femoroacetabular impingement that allows a complete articular joint view with maximum protection of the capsuloligamentous complex. This arthroscopic technique avoids injury to the capsuloligamentous complex, preventing the risk of postoperative instability. The diagnosis of femoroacetabular impingement was based on clinical and radiographic grounds. An alpha angle greater than 50° was considered pathologic. In this technique, the use of intra-articular devices (retractors) allows us to separate the capsular tissue from the femoral head-neck junction and mobilize the capsule, achieving an adequate joint view without performing a capsulotomy and, consequently, avoiding the complications of capsular damage.
Background and aim. Hepatocellular carcinoma (HCC) is the most common primary liver cancer diagno... more Background and aim. Hepatocellular carcinoma (HCC) is the most common primary liver cancer diagnosed worldwide. Deregulation of Wnt/beta-catenin pathway has been associated with the development of HCC in a substantial number of cases in Europe and far less in Asia. Nothing is known about this pathway in HCC cases from South America. This study aimed to investigate the frequency of mutations in beta-catenin gene (CTNNB1) and the subcellular localization of beta-catenin in HCC cases from Colombia. Material and methods. We determine by direct sequencing the frequency of mutations in exon 3 of CTNNB1 gene and by immunohistochemistry the subcellular localization of beta-catenin in 54 samples of HCC obtained from three pathology units in Bogota and Medellin cities. Results. Only three HCC cases (5.6%) were found mutated at residues (G34E, S45P, P44S, T41I) important for phosphorylation and ubiquitination of beta-catenin protein. Strikingly, nuclear or cytoplasmic accumulation of beta-cate...
This work addresses the automatic generation of conceptual models for XML-oriented databases, whi... more This work addresses the automatic generation of conceptual models for XML-oriented databases, which in many cases have little or no support for schemata. Our techniques are based on both an incremental clustering algorithm, which groups together the incoming XML documents according to their structural similarities, and a schema inference method, which maintains dynamically the schema of each detected document cluster. Our proposal takes into consideration the schema evolution. For this purpose, we have adapted the Toodor ...
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