Adriana Medina | Universidad Nacional de Tucuman (original) (raw)

Papers by Adriana Medina

Research paper thumbnail of Fly ash from a Mexican mineral coal I: Mineralogical and chemical characterization

Journal of Hazardous Materials, 2010

The properties of coal fly ash are strongly dependent on the geological origin and the combustion... more The properties of coal fly ash are strongly dependent on the geological origin and the combustion process of the coal. It is important to characterize regional fly ash in detail to ascertain its potential uses as raw material in the production of high value products. The physicochemical properties of fly ash coming from the "Jose Lopez Portillo" coal-fired power plant, Coahuila, Mexico (MFA), are presented in this work. A detailed study of trace elements, the chemical composition of the amorphous phase, thermal stability and the leaching of contaminant elements under different conditions are included. MFA is composed of mullite, quartz, calcite, magnetite and an amorphous phase. This material contains mainly silica (59.6%), alumina (22.8%) and magnetite (5.6%). Its amorphous phase (78.3%) has a high silica (49.4%) and alumina (14.4%) content. According to its mineralogical and chemical composition, MFA is potentially useful as a raw material for making cement, silica, and alumina, as well as low silica/alumina ratio zeolites. Deleterious elements could be removed during the zeolitization process or with an additional acid treatment. Because of its morphological properties and structural and thermal stability, MFA can be used in thermal isolation and refractory materials and as a support for heterogeneous catalysts.

Research paper thumbnail of Fly ash from a Mexican mineral coal. II. Source of W zeolite and its effectiveness in arsenic (V) adsorption

Journal of Hazardous Materials, 2010

Coal-fired plants in Coahuila (Mexico) produce highly reactive fly ash (MFA), which is used in a ... more Coal-fired plants in Coahuila (Mexico) produce highly reactive fly ash (MFA), which is used in a one-step process as a raw material in producing zeolite. We explored two routes in the synthesis of zeolite: (a) direct MFA zeolitization, which resulted in the formation of W zeolite with KOH and analcime with NaOH and (b) a MFA fusion route, which resulted in the formation of zeolite W or chabazite with KOH and zeolite X or P with NaOH. No residual crystalline phases were present. When LiOH was employed, ABW zeolite with quartz and mullite were obtained. For both zeolitization routes, the nature of the alkali (KOH, NaOH, LiOH), the alkali/MFA ratio (0.23-1.46), and the crystallization temperature and time (90-175 • C; 8-24 h) were evaluated. Additionally, the effect of temperature and time on MFA fusion was studied. W zeolite was obtained by both zeolitization methods. The direct route is preferred because it is a straightforward method using soft reaction conditions that results in a high yield of low cost zeolites with large crystal agglomerates. It was demonstrated that aluminum modified W zeolite has the ability to remove 99% of the arsenic (V) from an aqueous solution of Na 2 HAsO 4 ·7H 2 O originally containing 740 ppb.

Research paper thumbnail of BTBD18: A novel MLL partner gene in an infant with acute lymphoblastic leukemia and inv(11)(q13;q23)

Research paper thumbnail of RT-PCR diagnosis of recurrent rearrangements in pediatric acute lymphoblastic leukemia in Argentina

Leukemia Research, 2012

The present study was performed to establish the prevalence of the recurrent fusion transcripts i... more The present study was performed to establish the prevalence of the recurrent fusion transcripts in Argentinean pediatric patients with acute lymphoblastic leukemia (ALL). A total of 380 newly diagnosed children (including 50 infants and 44 T-ALL) were screened by RT-PCR; the incidence of recurrent rearrangements was: ETV6-RUNX1, 12.9%; TCF3-PBX1, 5.0%; BCR-ABL1, 1.6%; and MLL rearrangements, 10.5%. STIL-TAL1 was detected in 22.7% of T-ALL cases. In B-ALL cases, the pEFS was significantly influenced by the presence of genetic alterations. RT-PCR studies improved patients' stratification and also the overall outcome of children treated in a pediatric hospital from a developing country.

Research paper thumbnail of A novelAF9 breakpoint inMLL-AF9-positive acute monoblastic leukemia

Pediatric Blood & Cancer, 2008

MLL-AF9 is the most frequent MLL rearrangement in childhood acute myeloid leukemia (AML) and it m... more MLL-AF9 is the most frequent MLL rearrangement in childhood acute myeloid leukemia (AML) and it may be also found in acute lymphoblastic leukemia (ALL) of patients younger than 1-year-old (infants). We report a novel AF9 breakpoint site, located between previously reported sites A and B, detected in an infant who was diagnosed with AML-FAB M5. The occurrence of this new breakpoint should be considered when designing RT-PCR assays for the screening of MLL abnormalities. The precise characterization of the MLL-AF9 transcript is important to carry out the minimal residual disease analysis during the follow-up of the patients. Pediatr Blood Cancer 2008;50:869–871. © 2007 Wiley-Liss, Inc.

Research paper thumbnail of Community of Practice

Encyclopedia ofthe Social and Cultural Foundations of Education, 2009

Research paper thumbnail of Reading, History of

Encyclopedia ofthe Social and Cultural Foundations of Education, 2009

Research paper thumbnail of Context in Education

Encyclopedia ofthe Social and Cultural Foundations of Education, 2009

Research paper thumbnail of Application of Computer, Digital, and Telecommunications Technologies to the Clinical Preparation of Teachers

Research paper thumbnail of Reciprocal Teaching for the Primary Grades: “We Can Do It, Too!”

The Reading Teacher, 2009

... Paola Pilonieta. Adriana L. Medina. About the authors. full text - PDF. ... Many primary-grad... more ... Paola Pilonieta. Adriana L. Medina. About the authors. full text - PDF. ... Many primary-grade teachers have not always emphasized comprehension strategy instruction in their curriculum (Kragler, Walker, & Martin, 2005; Pearson & Duke, 2002; Reutzel et al., 2005). ...

Research paper thumbnail of 2 INVENTARIO ENERGÉTICO DE EDIFICIOS

El propósito de este capítulo es la creación de un protocolo para el análisis de los parámetros e... more El propósito de este capítulo es la creación de un protocolo para el análisis de los parámetros energéticos actuales de un cierto edificio, obteniendo información sobre el funcionamiento de éste a través de cuestionarios, inspecciones in situ, elaboración de perfiles de ocupación y horarios… Es decir, el objetivo final es la creación de un inventario energético detallado que, según el nivel al que se estime oportuno, permita la recogida de información, la realización de un prediagnóstico energético del edificio, o una evaluación detallada del mismo.

Research paper thumbnail of Fly ash from a Mexican mineral coal I: Mineralogical and chemical characterization

Journal of Hazardous Materials, 2010

The properties of coal fly ash are strongly dependent on the geological origin and the combustion... more The properties of coal fly ash are strongly dependent on the geological origin and the combustion process of the coal. It is important to characterize regional fly ash in detail to ascertain its potential uses as raw material in the production of high value products. The physicochemical properties of fly ash coming from the "Jose Lopez Portillo" coal-fired power plant, Coahuila, Mexico (MFA), are presented in this work. A detailed study of trace elements, the chemical composition of the amorphous phase, thermal stability and the leaching of contaminant elements under different conditions are included. MFA is composed of mullite, quartz, calcite, magnetite and an amorphous phase. This material contains mainly silica (59.6%), alumina (22.8%) and magnetite (5.6%). Its amorphous phase (78.3%) has a high silica (49.4%) and alumina (14.4%) content. According to its mineralogical and chemical composition, MFA is potentially useful as a raw material for making cement, silica, and alumina, as well as low silica/alumina ratio zeolites. Deleterious elements could be removed during the zeolitization process or with an additional acid treatment. Because of its morphological properties and structural and thermal stability, MFA can be used in thermal isolation and refractory materials and as a support for heterogeneous catalysts.

Research paper thumbnail of Fly ash from a Mexican mineral coal. II. Source of W zeolite and its effectiveness in arsenic (V) adsorption

Journal of Hazardous Materials, 2010

Coal-fired plants in Coahuila (Mexico) produce highly reactive fly ash (MFA), which is used in a ... more Coal-fired plants in Coahuila (Mexico) produce highly reactive fly ash (MFA), which is used in a one-step process as a raw material in producing zeolite. We explored two routes in the synthesis of zeolite: (a) direct MFA zeolitization, which resulted in the formation of W zeolite with KOH and analcime with NaOH and (b) a MFA fusion route, which resulted in the formation of zeolite W or chabazite with KOH and zeolite X or P with NaOH. No residual crystalline phases were present. When LiOH was employed, ABW zeolite with quartz and mullite were obtained. For both zeolitization routes, the nature of the alkali (KOH, NaOH, LiOH), the alkali/MFA ratio (0.23-1.46), and the crystallization temperature and time (90-175 • C; 8-24 h) were evaluated. Additionally, the effect of temperature and time on MFA fusion was studied. W zeolite was obtained by both zeolitization methods. The direct route is preferred because it is a straightforward method using soft reaction conditions that results in a high yield of low cost zeolites with large crystal agglomerates. It was demonstrated that aluminum modified W zeolite has the ability to remove 99% of the arsenic (V) from an aqueous solution of Na 2 HAsO 4 ·7H 2 O originally containing 740 ppb.

Research paper thumbnail of BTBD18: A novel MLL partner gene in an infant with acute lymphoblastic leukemia and inv(11)(q13;q23)

Research paper thumbnail of RT-PCR diagnosis of recurrent rearrangements in pediatric acute lymphoblastic leukemia in Argentina

Leukemia Research, 2012

The present study was performed to establish the prevalence of the recurrent fusion transcripts i... more The present study was performed to establish the prevalence of the recurrent fusion transcripts in Argentinean pediatric patients with acute lymphoblastic leukemia (ALL). A total of 380 newly diagnosed children (including 50 infants and 44 T-ALL) were screened by RT-PCR; the incidence of recurrent rearrangements was: ETV6-RUNX1, 12.9%; TCF3-PBX1, 5.0%; BCR-ABL1, 1.6%; and MLL rearrangements, 10.5%. STIL-TAL1 was detected in 22.7% of T-ALL cases. In B-ALL cases, the pEFS was significantly influenced by the presence of genetic alterations. RT-PCR studies improved patients' stratification and also the overall outcome of children treated in a pediatric hospital from a developing country.

Research paper thumbnail of A novelAF9 breakpoint inMLL-AF9-positive acute monoblastic leukemia

Pediatric Blood & Cancer, 2008

MLL-AF9 is the most frequent MLL rearrangement in childhood acute myeloid leukemia (AML) and it m... more MLL-AF9 is the most frequent MLL rearrangement in childhood acute myeloid leukemia (AML) and it may be also found in acute lymphoblastic leukemia (ALL) of patients younger than 1-year-old (infants). We report a novel AF9 breakpoint site, located between previously reported sites A and B, detected in an infant who was diagnosed with AML-FAB M5. The occurrence of this new breakpoint should be considered when designing RT-PCR assays for the screening of MLL abnormalities. The precise characterization of the MLL-AF9 transcript is important to carry out the minimal residual disease analysis during the follow-up of the patients. Pediatr Blood Cancer 2008;50:869–871. © 2007 Wiley-Liss, Inc.

Research paper thumbnail of Community of Practice

Encyclopedia ofthe Social and Cultural Foundations of Education, 2009

Research paper thumbnail of Reading, History of

Encyclopedia ofthe Social and Cultural Foundations of Education, 2009

Research paper thumbnail of Context in Education

Encyclopedia ofthe Social and Cultural Foundations of Education, 2009

Research paper thumbnail of Application of Computer, Digital, and Telecommunications Technologies to the Clinical Preparation of Teachers

Research paper thumbnail of Reciprocal Teaching for the Primary Grades: “We Can Do It, Too!”

The Reading Teacher, 2009

... Paola Pilonieta. Adriana L. Medina. About the authors. full text - PDF. ... Many primary-grad... more ... Paola Pilonieta. Adriana L. Medina. About the authors. full text - PDF. ... Many primary-grade teachers have not always emphasized comprehension strategy instruction in their curriculum (Kragler, Walker, & Martin, 2005; Pearson & Duke, 2002; Reutzel et al., 2005). ...

Research paper thumbnail of 2 INVENTARIO ENERGÉTICO DE EDIFICIOS

El propósito de este capítulo es la creación de un protocolo para el análisis de los parámetros e... more El propósito de este capítulo es la creación de un protocolo para el análisis de los parámetros energéticos actuales de un cierto edificio, obteniendo información sobre el funcionamiento de éste a través de cuestionarios, inspecciones in situ, elaboración de perfiles de ocupación y horarios… Es decir, el objetivo final es la creación de un inventario energético detallado que, según el nivel al que se estime oportuno, permita la recogida de información, la realización de un prediagnóstico energético del edificio, o una evaluación detallada del mismo.