The Atacama Desert of northern Chile may be the most lifeless place on Earth, yet microorganisms ... more The Atacama Desert of northern Chile may be the most lifeless place on Earth, yet microorganisms do survive in some areas. The distribution and diversity of life in the Atacama remains unexplored and is the focus of the Life in the Atacama project. To conduct this investigation, survey traverses across the desert with biologic and geologic instruments will allow us to create biogeographic maps. We accomplish these surveys with an autonomous astrobiology rover. In this paper we motivate the Life in the Atacama project and report on the second of three field seasons of scientific investigation and technical experiments in Chile. We describe the rover, instruments, algorithms and assess intermediate results. These results provide insight into the design of an effective robotic astrobiologist for future planetary investigations and into the best methods to conduct astrobiologic surveys.
Revista Española de Cardiología (English Edition), 2007
we carried out percutaneous patent ductus arteriosus closure using a Nit-Occlud device in 28 pati... more we carried out percutaneous patent ductus arteriosus closure using a Nit-Occlud device in 28 patients, who had a median age of 1.8 years (range 0.5-21 years) and a median weight of 10.9 kg (range 5.9-64 kg). The ductus arteriosus had several different morphologic forms, and there was one postsurgical recanalization of the ductus arteriosus. The median minimum ductal diameter was 1.8 mm and the median maximum aortic ampulla diameter was 6.5 mm. The occlusion rate immediately after intervention was 53.5%, which increased to 95.2% by 12 months and to 100% by 18 months. The median follow-up time was 20.5 months. The Nit-Occlud device provided an effective and safe means of patent ductus arteriosus closure, irrespective of ductus morphology.
The recent explosion in technology, in particular in computer and digitizing systems, has many im... more The recent explosion in technology, in particular in computer and digitizing systems, has many implications for heritage language maintenance and learning. In particular, authentic language usage can be easily recorded and preserved for those goals. That same explosion, however, can lead to a less than appropriate implementation of technology for language maintenance and learning. Further, certain cultural boundaries can make it difficult to have access to authentic language usage, particularly by out-group individuals who work on indigenous languages. This paper presents a pilot study that attempts to both implement technology in an appropriate manner and surmount the problems faced by out-group language researchers by training an in-group member, in this case a speaker of Navajo, in the methodology and technology necessary for recording and preserving her heritage language. The results of this work are discussed, as well as the role of computer and digitizing technology in languag...
Abstract: Many researchers investigating the maintenance and loss of non-English languages in the... more Abstract: Many researchers investigating the maintenance and loss of non-English languages in the US base their work on fairly homogeneous language groups, those who have immigrated here during a relatively restricted period of time. The European-origin migrations during the early decades of the twentieth century represent these types of language communities. However, Spanish is not strictly an immigrant language when compared to other non-English, non-indigenous languages. It shares in common with ...
Abstract: For over thirty years, research on Spanish in the US has demonstrated an inexorable los... more Abstract: For over thirty years, research on Spanish in the US has demonstrated an inexorable loss of the language among Spanish speaking populations. This study shows, however, that analyses of 1980, 1990, and 2000 US Census data, using an innovative approach known as a synthetic cohort analysis, reveal a high degree of transmission of Spanish from first generation to second generation speakers. For the purpose of tracking reported language use of individuals starting at ages 5-7 and ending at ages 15-17, data ...
ABSTRACT Many Spanish for Native Speakers (SNS) instructional approaches are based on the idea th... more ABSTRACT Many Spanish for Native Speakers (SNS) instructional approaches are based on the idea that there exist invariable spoken and written “standards” of the language that are preferable over other varieties and that will benefit students when acquired. However, such invariable varieties of any language do not exist, and thus a decision must be made as to which dialect and written variety will be used in SNS instruction. This decision is political in nature, and one that cannot be avoided. Basing this decision on sociolinguistic ...
ABSTRACT Demographic changes in the US population are reflected in the students entering Spanish ... more ABSTRACT Demographic changes in the US population are reflected in the students entering Spanish language instruction programs. These programs face a student body with a wide range of language skills; from those with no knowledge of Spanish to those who are natively fluent in the language. In response to the increasing number of students who enter Spanish classes with some degree of heritage language skills, many programs across the nation have instituted what are commonly called Spanish for Native Speakers (SNS) ...
Abstract: The rapidly increasing number of Spanish speakers in the United States has resulted in ... more Abstract: The rapidly increasing number of Spanish speakers in the United States has resulted in increased national linguistic tensions. Groups such as US English aim to restrict the use of all non-English languages in general, and Spanish in particular, in certain public domains. At the same time, another group, which includes a nucleus of language scholars, is engaging in efforts to change or suppress the use of US Spanish, particularly in the domain of education. In this article, the author asserts that the arguments put forward by ...
The presence of ochratoxin A (OTA) in human blood has been reported for many countries, especiall... more The presence of ochratoxin A (OTA) in human blood has been reported for many countries, especially in Europe. However, so far no report exists concerning such a presence in Argentina. The aim of this study was to assess OTA concentration in human plasma in two different areas of Buenos Aires province. OTA was determined by high-performance liquid chromatography (HPLC) in 199 plasma samples from blood donors in Mar del Plata and 236 from General Rodríguez. Solid-phase extraction with Bakerbond® C-18 cartridge and a final purification with Ochraprep® immunoaffinity columns was employed. The limit of quantification of ochratoxin A was 0.019ngml -1 and the confirmation of OTA was by formation of ochratoxin A methyl ester. The results showed that 63.8% of human plasma samples from Mar del Plata and 62.3% from General Rodríguez were positive for OTA, with Winsorized means of 0.15 and 0.43ngml -1 , respectively. It is important to continue the research to detect the foods responsible of the presence of OTA in plasma.
ABSTRACT Objective: To analyze the existence of association between the left ventricular myocardi... more ABSTRACT Objective: To analyze the existence of association between the left ventricular myocardial systolic function evaluated by midwall fractional shortening (MFs) and the behavior of left ventricular diastolic function evaluated by the E/A ratio in asymtomatic hypertensive treated patients, using Doppler echocardiography and the pulsed tissue Doppler.Methods: A population of 45 mild-to-moderate hypertensive patients (34 men and 11 women) with treatment and average age 47 ± 9, years were studied. Clinical examination, electrocardiogram, Doppler echocardiography, and pulsed tissue Doppler in rest were performed on all of the patients. The following variables were taken into account: height, weight, body surface (BS), body mass index (BMI), heart rate (HR), systolic and diastolic blood pressure (SBP, DBP), left ventricular dimensions and thicknesses (LVIDd, LVIDs, IVSDd, IVSDs, PWTd and PWTs, endocardial fractional shortening (EFs), ejection fraction (EF), relative wall thickness (RWT), left ventricular mass (LVM), left ventricular mass index (LVMI), systolic volume (SV), systolic volume index (SVI), circumferential end-systolic wall stress (CESS), left atrial dimension (LAD), E(E) and A (A) peak velocity waves of diastolic filling, E/A ratio (E/A), deceleration time (DT), isovolumic relaxation time (IVRT), A wave duration(AD), E tisular (Et), A tisular (At), S tisular (St) peak velocity waves and Et/At ratio. The total population was separated into two groups: G1 formed by 27 (60%) patients with normal MFs (>19%) and G2 formed by 18 (40%) patients with diminished MFs (<19%). By means of the Student's t-test, the means of variables of both groups were compared. Using the chi-squared independence test for qualitative variables and the test of diferences for two proporcions, the relation existing between the MFs and the E/A and Et/At of G1 and G2 were analyzed, taking as normal value when it is >1 and abnormal value when it is <1 in both variables. The p value was considered significantly at <0.05.Results: The G1 (MFs > 19%) showed values significantly higher in EFs, EF, SV, SVI, E and E/A, and significantly lower values in A (p < 0.05). The rest of the studied variables did not show significant differences. A comparison of the MFs with E/A and Et/At by means of the chi-squared test showed a significant dependence relation (p < 0.05). The analysis of the proportions showed that 89% of the patients with diminished MF (>19%) had a E/A <1 (p < 0.05) and 72% of the same group had a Et/At <1 (p < 0.05).Conclusion: In studied hypertensive patients, a MFs normal (>19%) was associated with a better left ventricular endocardial systolic function and with a better diastolic function evaluated by means of the E, A, and E/A of the ventricular filling. A significant dependence relation exists between la MFs and the diastolic function. Most of the hypertensive patients with diminished MFs show a worsening of the diastolic function evaluated by the E/A ratio of ventricular filling as well as the Et/At ratio of the pulse tissue Doppler.
The aquifer system, which is the resource of drinkable water for the city of Milano (Italy), is a... more The aquifer system, which is the resource of drinkable water for the city of Milano (Italy), is a multilayered aquifer, characterised by sandy-gravel units, interconnected by discontinuous aquitards. Models of ground water flow for this area have already been developed both at the local scale (0.25 km2) and at the scale of the whole city (about 400 km2). Here we present a quasi-three dimensional model, based on a con-servative finite difference scheme, to simulate ground water flow over a larger area (612 km2) which ...
The Chilean Atacama Desert is the most arid region on Earth and in several ways analogous to Mars... more The Chilean Atacama Desert is the most arid region on Earth and in several ways analogous to Mars. Evidence suggests that the interior of the Atacama is lifeless, yet where the desert meets the Pacific coastal range dessication-tolerant microorganisms are known to exist. The gradient of biodiversity and habitats in the Atacama's subregions remain unexplored and are the focus of the Life in the Atacama project.
LITA develops and field tests a long-range automated rover and a science payload to search for mi... more LITA develops and field tests a long-range automated rover and a science payload to search for microbial life in the Atacama. The Atacama's evolution provides a unique training ground for designing and testing exploration strategies and life detection methods for the search for life on Mars.
Proc. 8th International Symposium on Artificial Intelligence, Robotics and Automation in Space, Sep 1, 2005
The Atacama Desert of northern Chile may be the most lifeless place on Earth, yet microorganisms ... more The Atacama Desert of northern Chile may be the most lifeless place on Earth, yet microorganisms do survive in some areas. The distribution and diversity of life in the Atacama remains unexplored and is the focus of the Life in the Atacama project. To conduct this investigation, survey traverses across the desert with biologic and geologic instruments will allow us to create biogeographic maps. We accomplish these surveys with an autonomous astrobiology rover. In this paper we motivate the Life in the Atacama project ...
The Atacama Desert of northern Chile may be the most lifeless place on Earth, yet microorganisms ... more The Atacama Desert of northern Chile may be the most lifeless place on Earth, yet microorganisms do survive in some areas. The distribution and diversity of life in the Atacama remains unexplored and is the focus of the Life in the Atacama project. To conduct this investigation, survey traverses across the desert with biologic and geologic instruments will allow us to create biogeographic maps. We accomplish these surveys with an autonomous astrobiology rover. In this paper we motivate the Life in the Atacama project and report on the second of three field seasons of scientific investigation and technical experiments in Chile. We describe the rover, instruments, algorithms and assess intermediate results. These results provide insight into the design of an effective robotic astrobiologist for future planetary investigations and into the best methods to conduct astrobiologic surveys.
Revista Española de Cardiología (English Edition), 2007
we carried out percutaneous patent ductus arteriosus closure using a Nit-Occlud device in 28 pati... more we carried out percutaneous patent ductus arteriosus closure using a Nit-Occlud device in 28 patients, who had a median age of 1.8 years (range 0.5-21 years) and a median weight of 10.9 kg (range 5.9-64 kg). The ductus arteriosus had several different morphologic forms, and there was one postsurgical recanalization of the ductus arteriosus. The median minimum ductal diameter was 1.8 mm and the median maximum aortic ampulla diameter was 6.5 mm. The occlusion rate immediately after intervention was 53.5%, which increased to 95.2% by 12 months and to 100% by 18 months. The median follow-up time was 20.5 months. The Nit-Occlud device provided an effective and safe means of patent ductus arteriosus closure, irrespective of ductus morphology.
The recent explosion in technology, in particular in computer and digitizing systems, has many im... more The recent explosion in technology, in particular in computer and digitizing systems, has many implications for heritage language maintenance and learning. In particular, authentic language usage can be easily recorded and preserved for those goals. That same explosion, however, can lead to a less than appropriate implementation of technology for language maintenance and learning. Further, certain cultural boundaries can make it difficult to have access to authentic language usage, particularly by out-group individuals who work on indigenous languages. This paper presents a pilot study that attempts to both implement technology in an appropriate manner and surmount the problems faced by out-group language researchers by training an in-group member, in this case a speaker of Navajo, in the methodology and technology necessary for recording and preserving her heritage language. The results of this work are discussed, as well as the role of computer and digitizing technology in languag...
Abstract: Many researchers investigating the maintenance and loss of non-English languages in the... more Abstract: Many researchers investigating the maintenance and loss of non-English languages in the US base their work on fairly homogeneous language groups, those who have immigrated here during a relatively restricted period of time. The European-origin migrations during the early decades of the twentieth century represent these types of language communities. However, Spanish is not strictly an immigrant language when compared to other non-English, non-indigenous languages. It shares in common with ...
Abstract: For over thirty years, research on Spanish in the US has demonstrated an inexorable los... more Abstract: For over thirty years, research on Spanish in the US has demonstrated an inexorable loss of the language among Spanish speaking populations. This study shows, however, that analyses of 1980, 1990, and 2000 US Census data, using an innovative approach known as a synthetic cohort analysis, reveal a high degree of transmission of Spanish from first generation to second generation speakers. For the purpose of tracking reported language use of individuals starting at ages 5-7 and ending at ages 15-17, data ...
ABSTRACT Many Spanish for Native Speakers (SNS) instructional approaches are based on the idea th... more ABSTRACT Many Spanish for Native Speakers (SNS) instructional approaches are based on the idea that there exist invariable spoken and written “standards” of the language that are preferable over other varieties and that will benefit students when acquired. However, such invariable varieties of any language do not exist, and thus a decision must be made as to which dialect and written variety will be used in SNS instruction. This decision is political in nature, and one that cannot be avoided. Basing this decision on sociolinguistic ...
ABSTRACT Demographic changes in the US population are reflected in the students entering Spanish ... more ABSTRACT Demographic changes in the US population are reflected in the students entering Spanish language instruction programs. These programs face a student body with a wide range of language skills; from those with no knowledge of Spanish to those who are natively fluent in the language. In response to the increasing number of students who enter Spanish classes with some degree of heritage language skills, many programs across the nation have instituted what are commonly called Spanish for Native Speakers (SNS) ...
Abstract: The rapidly increasing number of Spanish speakers in the United States has resulted in ... more Abstract: The rapidly increasing number of Spanish speakers in the United States has resulted in increased national linguistic tensions. Groups such as US English aim to restrict the use of all non-English languages in general, and Spanish in particular, in certain public domains. At the same time, another group, which includes a nucleus of language scholars, is engaging in efforts to change or suppress the use of US Spanish, particularly in the domain of education. In this article, the author asserts that the arguments put forward by ...
The presence of ochratoxin A (OTA) in human blood has been reported for many countries, especiall... more The presence of ochratoxin A (OTA) in human blood has been reported for many countries, especially in Europe. However, so far no report exists concerning such a presence in Argentina. The aim of this study was to assess OTA concentration in human plasma in two different areas of Buenos Aires province. OTA was determined by high-performance liquid chromatography (HPLC) in 199 plasma samples from blood donors in Mar del Plata and 236 from General Rodríguez. Solid-phase extraction with Bakerbond® C-18 cartridge and a final purification with Ochraprep® immunoaffinity columns was employed. The limit of quantification of ochratoxin A was 0.019ngml -1 and the confirmation of OTA was by formation of ochratoxin A methyl ester. The results showed that 63.8% of human plasma samples from Mar del Plata and 62.3% from General Rodríguez were positive for OTA, with Winsorized means of 0.15 and 0.43ngml -1 , respectively. It is important to continue the research to detect the foods responsible of the presence of OTA in plasma.
ABSTRACT Objective: To analyze the existence of association between the left ventricular myocardi... more ABSTRACT Objective: To analyze the existence of association between the left ventricular myocardial systolic function evaluated by midwall fractional shortening (MFs) and the behavior of left ventricular diastolic function evaluated by the E/A ratio in asymtomatic hypertensive treated patients, using Doppler echocardiography and the pulsed tissue Doppler.Methods: A population of 45 mild-to-moderate hypertensive patients (34 men and 11 women) with treatment and average age 47 ± 9, years were studied. Clinical examination, electrocardiogram, Doppler echocardiography, and pulsed tissue Doppler in rest were performed on all of the patients. The following variables were taken into account: height, weight, body surface (BS), body mass index (BMI), heart rate (HR), systolic and diastolic blood pressure (SBP, DBP), left ventricular dimensions and thicknesses (LVIDd, LVIDs, IVSDd, IVSDs, PWTd and PWTs, endocardial fractional shortening (EFs), ejection fraction (EF), relative wall thickness (RWT), left ventricular mass (LVM), left ventricular mass index (LVMI), systolic volume (SV), systolic volume index (SVI), circumferential end-systolic wall stress (CESS), left atrial dimension (LAD), E(E) and A (A) peak velocity waves of diastolic filling, E/A ratio (E/A), deceleration time (DT), isovolumic relaxation time (IVRT), A wave duration(AD), E tisular (Et), A tisular (At), S tisular (St) peak velocity waves and Et/At ratio. The total population was separated into two groups: G1 formed by 27 (60%) patients with normal MFs (>19%) and G2 formed by 18 (40%) patients with diminished MFs (<19%). By means of the Student's t-test, the means of variables of both groups were compared. Using the chi-squared independence test for qualitative variables and the test of diferences for two proporcions, the relation existing between the MFs and the E/A and Et/At of G1 and G2 were analyzed, taking as normal value when it is >1 and abnormal value when it is <1 in both variables. The p value was considered significantly at <0.05.Results: The G1 (MFs > 19%) showed values significantly higher in EFs, EF, SV, SVI, E and E/A, and significantly lower values in A (p < 0.05). The rest of the studied variables did not show significant differences. A comparison of the MFs with E/A and Et/At by means of the chi-squared test showed a significant dependence relation (p < 0.05). The analysis of the proportions showed that 89% of the patients with diminished MF (>19%) had a E/A <1 (p < 0.05) and 72% of the same group had a Et/At <1 (p < 0.05).Conclusion: In studied hypertensive patients, a MFs normal (>19%) was associated with a better left ventricular endocardial systolic function and with a better diastolic function evaluated by means of the E, A, and E/A of the ventricular filling. A significant dependence relation exists between la MFs and the diastolic function. Most of the hypertensive patients with diminished MFs show a worsening of the diastolic function evaluated by the E/A ratio of ventricular filling as well as the Et/At ratio of the pulse tissue Doppler.
The aquifer system, which is the resource of drinkable water for the city of Milano (Italy), is a... more The aquifer system, which is the resource of drinkable water for the city of Milano (Italy), is a multilayered aquifer, characterised by sandy-gravel units, interconnected by discontinuous aquitards. Models of ground water flow for this area have already been developed both at the local scale (0.25 km2) and at the scale of the whole city (about 400 km2). Here we present a quasi-three dimensional model, based on a con-servative finite difference scheme, to simulate ground water flow over a larger area (612 km2) which ...
The Chilean Atacama Desert is the most arid region on Earth and in several ways analogous to Mars... more The Chilean Atacama Desert is the most arid region on Earth and in several ways analogous to Mars. Evidence suggests that the interior of the Atacama is lifeless, yet where the desert meets the Pacific coastal range dessication-tolerant microorganisms are known to exist. The gradient of biodiversity and habitats in the Atacama's subregions remain unexplored and are the focus of the Life in the Atacama project.
LITA develops and field tests a long-range automated rover and a science payload to search for mi... more LITA develops and field tests a long-range automated rover and a science payload to search for microbial life in the Atacama. The Atacama's evolution provides a unique training ground for designing and testing exploration strategies and life detection methods for the search for life on Mars.
Proc. 8th International Symposium on Artificial Intelligence, Robotics and Automation in Space, Sep 1, 2005
The Atacama Desert of northern Chile may be the most lifeless place on Earth, yet microorganisms ... more The Atacama Desert of northern Chile may be the most lifeless place on Earth, yet microorganisms do survive in some areas. The distribution and diversity of life in the Atacama remains unexplored and is the focus of the Life in the Atacama project. To conduct this investigation, survey traverses across the desert with biologic and geologic instruments will allow us to create biogeographic maps. We accomplish these surveys with an autonomous astrobiology rover. In this paper we motivate the Life in the Atacama project ...
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