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Search Results: 1 - 10 of 379797 matches for " Juan P. Díaz "
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Origin and SEM analysis of aerosols in the high mountain of Tenerife (Canary Islands)  [PDF]
Juan D. Delgado, Omaira E. García, Ana M. Díaz, Juan P. Díaz, Francisco J. Expósito, Emilio Cuevas, Xavier Querol, Andrés Alastuey, Sonia Castillo
Natural Science (NS) , 2010, DOI: 10.4236/ns.2010.210139
Abstract: Focusing on aerosolized matter of relevance to respiratory health, a major public health issue worldwide, we studied mineral and biological aerosol (bioaerosol) composition (TSP and PM2.5) and geographical origins during dust intrusions in the Canary Islands. Seven days’ back- ward trajectories were assessed daily during March 2004 with the ends of back trajectories being the sampling station of Iza?a (high moun- tain, 2360 m a.s.l. at the Ca?adas del Teide National Park, Tenerife island), a free troposphere site allowing characterization of dust with low influence of other pollutant sources. Scanning electron microscopy (SEM) was used to survey major types of airborne particles in the dust plumes. Control, non-intrusion conditions correspond to Atlantic oceanic middle troposphere (OMT) air masses. Of the 14 samples taken, 1 corresponded to a control (clear atmosphere conditions), and the remaining 13 to dust intrusions, with the following sources: African Dust; EAM: mixture of Europe, Africa and Oceanic; MaA: maritime aerosols. Of the air masses, 79% were directly transported to the islands from Africa, and an increase of African dust events was detected when comparing with a 52-year previous data sequence. Quartz microcristals and aggregates of quartz and platy clay were the dominant minerals identified, with marine salt and gypsum also present. Freshwater diatom tests (from two Aulacoseira species) represented the most important biogenic aerosols, although fungi and pollen were also detected. The diverse and complex mixture of respirable particles in large quantities in airborne dust, especially from nearby Sahara and from the Sahelian region, is of maximum interest for air- way pathology in the Canaries, including the highly visited highlands in Tenerife.
FIRST RECORD OF THE PIGMY SQUID, PICKFORDIATEUTHIS PULCHELLA (CEPHALOPODA: MYOPSIDA: LOLIGINIDAE), FROM THE CARIBBEAN COAST OF COLOMBIA
Arango,Claudia P.; Díaz,Juan M.;
Boletín de Investigaciones Marinas y Costeras - INVEMAR , 1996,
Abstract: se registra por primera vez para el caribe colombiano el calamar "pigmeo", pickfordiateuthis pulchella, a partir de cuatro hembras colectadas en cercanías de santa marta. aunque esta especie no era conocida de la costa continental del norte de suramérica, el alto grado de dispersión de los pocos registros conocidos sugiere que su distribución en el atlántico occidental es bastante amplia.
Estado de Conocimiento de los Anfibios de Chile
Ortiz Z,Juan Carlos; Díaz-Páez,Helen;
Gayana (Concepción) , 2006, DOI: 10.4067/S0717-65382006000100017
Abstract: trough a historical summary of the herpetology in chile, this paper reports a comparison among the book of j. m. cei in 1962 "batracios de chile", until the current days. also, we elaborated a synthesis of the geographical distribution of the different species of amphibians in chile and we signaled the species shared with the bordering countries. finally, the conservation categories for the different species, the institutions where the material type is deposited and the amphibians research centers presents in chile are given. finally, deficit areas of the knowledge of this taxon, are discussed.
HABITOS ALIMENTARIOS DE PLEURODEMA THAUL (ANURA, LEPTODACTYLIDAE), EN CONCEPCION, CHILE
Díaz-Páez,Helen; Ortiz,Juan Carlos;
Gayana (Concepción) , 2003, DOI: 10.4067/S0717-65382003000100004
Abstract: we examined the diet for four eyes toad (pleurodema thaul) in hualpén (talcahuano, chile). the study was carried out during the breeding season (june - december) in 2000 and 2001. these anurans consume fewer preys during the breeding season, and they present a low occurrence frequency (50.63%). the results show the p. thaul diet include for arthropods (iri = 0.92), with a lower consumption of vegetables (iri = 0.035). we determined a high diversity of prey, with 37 taxa of invertebrates. the alimentary items dipteral and arachnids are the most common. no relationships occurred between the size of the preys and the size of the anurans
Evaluación del estado de conservación de los anfibios en Chile
DíAZ-PáEZ,HELEN; ORTIZ,JUAN CARLOS;
Revista chilena de historia natural , 2003, DOI: 10.4067/S0716-078X2003000300014
Abstract: at present, amphibians are one of the groups with the most from conservation problems. the decline that is taking place in numerous amphibian populations around the world has led herpetologists to recognize the urgency of studying topics related to the biology and conservation status of this group. in chile, numerous proposals exist to categorize the conservation status of flora as well as fauna at both national and regional levels. however, most of these works have used qualitative analysis. because quantifiable data is not available, proposals of conservation status are based on field observations and researcher experience. the application of a more quantifiable method is necessary in the categorization of amphibians in order to detect and recognize the factors that could have an impact on the decrease of amphibian populations. the present work gathers the information available for the diverse taxa of chilean amphibians and evaluates the conservation status of this fauna by means of the addition index (sumin), elaborated by reca et al. (1994) and the proposal for the international union for the conservation of nature (iucn 2001). results of the application of these methodologies are compared with the previous evaluations.
Enfoque diagnóstico y terapéutico de los pacientes adultos con sospecha de sinusitis aguda
FICA C,ALBERTO; DíAZ P,JUAN CARLOS;
Revista chilena de infectología , 2003, DOI: 10.4067/S0716-10182003000300006
Abstract: acute bacterial sinusitis (abs) is a common cause of morbidity and office consultation in adult patients and should be distinguished from a viral cause. most patients will recover spontaneously even without antibiotic treatment, although antimicrobials reduce abs symptoms and their severity. different strategies can be used to diagnose abs, being bacterial culture after sinus puncture the gold standard method, although this invasive alternative can not be routinely recommended. case detection by a specific constellation of sign and symptoms offer a reasonable sensitivity and specificity (~76% each), quite similar to the performance of conventional radiological studies but at a lesser cost. ultrasound and tomographic studies do not improve specificity and are less available or more expensive to perform. amoxicillin continues to be the preferred antimicrobial due to its efficacy, tolerance and low cost. other compounds such as macrolides, cefalosporins, respiratory quinolones and ketolides do not enhance efficacy or safety and are associated with higher acquisition costs. penicillin resistant pneumococcal isolates do no affect therapy of extrameningeal infections such as abs due to the moderate increment of the minimal inhibitory concentration for penicillin. resistance to cotrimoxazole among pneumococcal isolates precludes its use in chile.
HABITOS ALIMENTARIOS DE PLEURODEMA THAUL (ANURA, LEPTODACTYLIDAE), EN CONCEPCION, CHILE FEEDING HABITS OF PLEURODEMA THAUL (ANURA, LEPTODACTYLIDAE), IN CONCEPCIóN, CHILE
Helen Díaz-Páez,Juan Carlos Ortiz
Gayana (Concepción) , 2003,
Abstract: Se analizó la dieta de una población del sapito de cuatro ojos (Pleurodema thaul) de la localidad de Hualpén (Talcahuano, Chile). El estudio se realiza durante los períodos reproductivos (junio-diciembre) que comprenden los a os 2000 y 2001. Estos anuros destinan una menor importancia al consumo de presas durante la época reproductiva, por lo que presentan una baja frecuencia de ocurrencia (50,63%). La dieta de P. thaul está compuesta fundamentalmente de artrópodos (IRI = 0,92), con un consumo de menor importancia de vegetales (IRI = 0,035). Se determinó una alta diversidad de ítemes de presa (37 taxa). Los ítemes alimentarios dípteros y arácnidos son los más comunes. No se detectan relaciones entre el tama o de las presas y el tama o de los anuros We examined the diet for four eyes toad (Pleurodema thaul) in Hualpén (Talcahuano, Chile). The study was carried out during the breeding season (June - December) in 2000 and 2001. These anurans consume fewer preys during the breeding season, and they present a low occurrence frequency (50.63%). The results show the P. thaul diet include for arthropods (IRI = 0.92), with a lower consumption of vegetables (IRI = 0.035). We determined a high diversity of prey, with 37 taxa of invertebrates. The alimentary items dipteral and arachnids are the most common. No relationships occurred between the size of the preys and the size of the anurans
Estado de Conocimiento de los Anfibios de Chile Current State of Knowledge about the Amphibians of Chile
Juan Carlos Ortiz Z,Helen Díaz-Páez
Gayana (Concepción) , 2006,
Abstract: Se entrega un resumen histórico del desarrollo de la herpetología en Chile, con una comparación desde la situación entregada por el libro de J.M. Cei en 1962, "Batracios de Chile", hasta la situación actual. Además, se entrega una síntesis de la distribución geográfica de las diferentes especies de anfibios en Chile y se indican aquellas que son compartidas con los países limítrofes. Se dan a conocer las categorías de conservación en que se encuentran las diferentes especies, las instituciones donde se guarda el material tipo y los centros de investigación donde se realiza investigación en anfibios en Chile. Finalmente se discute las áreas deficitarias del conocimiento de este taxón. Trough a historical summary of the herpetology in Chile, this paper reports a comparison among the book of J. M. Cei in 1962 "Batracios de Chile", until the current days. Also, we elaborated a synthesis of the geographical distribution of the different species of amphibians in Chile and we signaled the species shared with the bordering countries. Finally, the conservation categories for the different species, the institutions where the material type is deposited and the amphibians research centers presents in Chile are given. Finally, deficit areas of the knowledge of this taxon, are discussed.
Evaluación del estado de conservación de los anfibios en Chile Assessment of the conservation status of amphibians in Chile
HELEN DíAZ-PáEZ,JUAN CARLOS ORTIZ
Revista chilena de historia natural , 2003,
Abstract: Los anfibios son uno de los grupos con mayores problemas de conservación en la actualidad. La declinación que se produce en numerosas poblaciones a nivel mundial ha llevado a los herpetólogos a reconocer la urgencia de abordar temas relacionados a la biología y estado de conservación de este grupo. En Chile existen numerosas propuestas para categorizar en estados de conservación, tanto a flora como fauna. De allí, que el estado de conservación de la fauna de anfibios haya sido evaluado a nivel nacional y regional. Sin embargo, la revisión de estos trabajos denota el uso reiterado de análisis cualitativos que carecen de datos cuantificables, estando sujetas a observaciones de campo y a la experiencia de los investigadores. Se hace necesario aplicar un método más cuantificable en la categorización de anfibios de manera que sea posible detectar y reconocer los factores que podrían incidir en la disminución de las poblaciones. El presente trabajo recopila la información disponible para los diversos taxa de anfibios chilenos, y evalúa el estado de conservación de la fauna de anfibios que habita en Chile por medio de la adición del índice SUMIN elaborado por Reca et al. (1994) y la propuesta por la Unión Internacional para la Conservación de la Naturaleza (IUCN 2001). Se comparan los resultados de la aplicación de estas metodologías con las evaluaciones previas. At present, amphibians are one of the groups with the most from conservation problems. The decline that is taking place in numerous amphibian populations around the world has led herpetologists to recognize the urgency of studying topics related to the biology and conservation status of this group. In Chile, numerous proposals exist to categorize the conservation status of flora as well as fauna at both national and regional levels. However, most of these works have used qualitative analysis. Because quantifiable data is not available, proposals of conservation status are based on field observations and researcher experience. The application of a more quantifiable method is necessary in the categorization of amphibians in order to detect and recognize the factors that could have an impact on the decrease of amphibian populations. The present work gathers the information available for the diverse taxa of Chilean amphibians and evaluates the conservation status of this fauna by means of the Addition Index (SUMIN), elaborated by Reca et al. (1994) and the proposal for the International Union for the Conservation of Nature (IUCN 2001). Results of the application of these methodologies are compared with th
Enfoque diagnóstico y terapéutico de los pacientes adultos con sospecha de sinusitis aguda Diagnosis and treatment of adult patients with acute sinusitis suspicion
ALBERTO FICA C,JUAN CARLOS DíAZ P
Revista chilena de infectología , 2003,
Abstract: La sinusitis aguda bacteriana es una causa frecuente de consulta ambulatoria de pacientes adultos y debe ser distinguida de aquellos casos con etiología viral. Un alto porcentaje de los casos tiende a la resolución espontánea sin el concurso de un tratamiento antimicrobiano, aunque esta opción terapéutica permite acortar el período sintomático y aliviar la intensidad de los síntomas. Para reconocer adecuadamente los casos de sinusitis aguda bacteriana se dispone de diferentes estrategias diagnósticas. La alternativa de referencia, la punción sinusal con cultivo, es de carácter invasor y no es aplicable en atención primaria. La detección de casos mediante el reconocimiento de algunos síntomas y signos específicos ofrece una sensibilidad y especificidad razonable, similar al rendimiento asociado al estudio radiológico convencional y además de menor costo. El diagnóstico por ecografía o tomografía axial computarizada no incrementa los valores asociados a las estrategias se aladas. Amoxicilina continúa siendo el fármaco de elección en el manejo de esta condición, debido a su demostrada eficacia, tolerancia y bajo costo. El advenimiento de nuevos compuestos no ha superado la eficacia asociada a amoxicilina, así como tampoco la emergencia de aislamientos de S. pneumoniae o H. influenzae resistentes a penicilina ha limitado su utilidad clínica. La alta resistencia ante cotrimoxazol presente en aislamientos nacionales de S. pneumoniae impide su recomendación en nuestro medio como un antimicrobiano de primera línea. Los pacientes deben ser tratados por un período de 10 días. Acute bacterial sinusitis (ABS) is a common cause of morbidity and office consultation in adult patients and should be distinguished from a viral cause. Most patients will recover spontaneously even without antibiotic treatment, although antimicrobials reduce ABS symptoms and their severity. Different strategies can be used to diagnose ABS, being bacterial culture after sinus puncture the gold standard method, although this invasive alternative can not be routinely recommended. Case detection by a specific constellation of sign and symptoms offer a reasonable sensitivity and specificity (~76% each), quite similar to the performance of conventional radiological studies but at a lesser cost. Ultrasound and tomographic studies do not improve specificity and are less available or more expensive to perform. Amoxicillin continues to be the preferred antimicrobial due to its efficacy, tolerance and low cost. Other compounds such as macrolides, cefalosporins, respiratory quinolones and ketolides do
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