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1.
Water Sci Technol ; 67(1): 217-23, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23128642

RESUMEN

Wildland fire is an important disturbance factor that can cause severe ecological and watershed damage. Depending on fire severity and watershed extension, reservoir suspended solids concentration (SSC), which arrives through river load, is expected to increase. Satellite remote sensing is an alternative technique to measure SSC in a reservoir. In this paper we evaluate the applicability of multitemporal Landsat data for mapping and monitoring of the SSC in a reservoir whose watershed was exposed to fires. Besides, we aim to identify catchment areas that have been burned, estimating the level of burn severity that occurred because of the fire. The Landsat images were radiometrically, atmospherically and geometrically corrected. Using the differenced normalized burn ratio (dNBR) algorithm, the perimeter and severity of fire was mapped. A theoretical model to characterize the distribution of SSC using multitemporal Landsat data was developed. The relationship between burn severity maps, rainfall and SSC maps improved our understanding of management actions on a reservoir which suffers frequent wildfires on its watershed. The theoretical model here developed may be considered as a low cost measurement tool for water management authorities, particularly when in-situ data are not available.


Asunto(s)
Incendios , Tecnología de Sensores Remotos , Movimientos del Agua , Contaminantes Químicos del Agua/química , Ecosistema , Nave Espacial , Factores de Tiempo
2.
Water Sci Technol ; 66(12): 2722-30, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23109591

RESUMEN

Artificial thermal mixing of the water column is a common method of addressing water quality problems with the most popular method of destratification being the bubble curtain. The air or oxygen distribution along submerged multiport diffusers is based on similar basic principles as those of outfall disposal systems. Moreover, the disposal of sequestered greenhouse gases into the ocean, as recently proposed by several researchers to mitigate the global warming problem, requires analogous design criteria. In this paper, the influence of a bubble-plume is evaluated using full-scale temperature and water quality data collected in San Roque Reservoir, Argentina. A composite system consisting of seven separated diffusers connected to four 500 kPa compressors was installed at this reservoir by the end of 2008. The original purpose of this air bubble system was to reduce the stratification, so that the water body may completely mix under natural phenomena and remain well oxygenated throughout the year. By using a combination of the field measurements and modelling, this work demonstrates that thermal mixing by means of compressed air may improve water quality; however, if improperly sized or operated, such mixing can also cause deterioration. Any disruption in aeration during the destratification process, for example, may result in a reduction of oxygen levels due to the higher hypolimnetic temperatures. Further, the use of artificial destratification appears to have insignificant influence on reducing evaporation rates in relatively shallow impoundments such as San Roque reservoir.


Asunto(s)
Temperatura , Calidad del Agua , Abastecimiento de Agua , Argentina , Clorofila/análisis , Clorofila A , Simulación por Computador , Geografía , Oxígeno/análisis , Lluvia , Solubilidad , Propiedades de Superficie , Volatilización , Agua/química
3.
Cancer Invest ; 28(5): 452-8, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19863344

RESUMEN

It has been recently demonstrated that progranulin is overexpressed in ovarian cancer and that this protein is involved in the stimulation of cell proliferation, malignancy, and chemoresistance in ovarian cancer. The goal of the present study was to establish the differences in progranulin expression among normal, benign, and malignant ovarian tissues and to identify the signal transduction pathways activated by progranulin in an ovarian cancer cell line. Compared with benign tumors and normal ovarian tissue, progranulin mRNA and protein were overexpressed in malignant tumors. Survival analysis by the Kaplan-Meier method showed a correlation between high mRNA expression levels with poor survival outcome. Progranulin activated the MAPK-signaling pathway in NIH-OVCAR-3 cells. Progranulin expression may be potentially involved in the pathogenesis and malignant progression of ovarian cancer, and thus may represent a therapeutic target for this particular malignancy.


Asunto(s)
Péptidos y Proteínas de Señalización Intercelular/metabolismo , Neoplasias Ováricas/metabolismo , Ovario/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Apoptosis , Línea Celular , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular , Femenino , Humanos , Péptidos y Proteínas de Señalización Intercelular/genética , Sistema de Señalización de MAP Quinasas , Persona de Mediana Edad , Neoplasias Ováricas/mortalidad , Progranulinas
4.
Menopause ; 5(2): 86-9, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9689201

RESUMEN

OBJECTIVE: The purpose of this study was to assess differences in endometrial thickness, ultrasonographic characteristics, and histological and bleeding patterns in two groups of women according to the type and length of hormone replacement therapy (HRT) administered. DESIGN: Twenty-seven women were divided into two groups. Group I received oral conjugated estrogens 0.625 mg/day for 21 days, plus chlormadinone 2 mg the last 12 days, for a median length of 6.5 months' time. Group II received oral conjugated estrogens 0.625 mg/day plus chlormadinone 1 mg/day, both continuous and uninterrupted (n = 13), for a median length of 3 months' time. Using transvaginal ultrasound, endometrial thickness, refringence, and the presence of liquid in the uterine cavity were analyzed. An endometrial biopsy was performed the same day and the histological and bleeding patterns were described. Statistical analysis was performed with Mann-Whitney U test, Fisher's exact test, and Spearman correlation coefficient. RESULTS: Results of these tests showed that liquid in the uterine cavity and secretory endometrium were frequently found in those with sequential schedule (Group I); regular uterine bleeding was also frequent in this group. Negative correlation coefficients were found in this group between duration of HRT and endometrial thickness and uterine bleeding patterns, and in the continuous schedule group, between the duration of HRT and uterine bleeding pattern. CONCLUSIONS: We conclude that endometrial and ultrasonographic changes depend on the type of HRT schedule and the duration of therapy.


Asunto(s)
Acetato de Clormadinona/farmacología , Endometrio/efectos de los fármacos , Terapia de Reemplazo de Estrógeno , Estrógenos Conjugados (USP)/farmacología , Congéneres de la Progesterona/farmacología , Administración Oral , Adulto , Acetato de Clormadinona/administración & dosificación , Esquema de Medicación , Endometrio/diagnóstico por imagen , Endometrio/metabolismo , Endometrio/patología , Estrógenos Conjugados (USP)/administración & dosificación , Femenino , Humanos , Persona de Mediana Edad , Congéneres de la Progesterona/administración & dosificación , Ultrasonografía , Hemorragia Uterina/inducido químicamente
5.
J Stud Alcohol ; 60(6): 790-9, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10606491

RESUMEN

OBJECTIVE: The study reports the process of translation into Spanish and adaptation to the Hispanic culture of the Alcohol Use Disorder and Associated Disabilities Schedule (AUDADIS). This instrument is a structured diagnostic interview schedule specifically developed for the assessment of substance-related disorders and their comorbid disorders and disabilities. METHOD: A random sample (N = 169) of adults from a primary health care clinic in Puerto Rico was selected. The test-retest reliability of the instrument was examined across time and across interviewers, and the validity was assessed by comparing computer-derived diagnoses obtained through the administration of lay interviewers with best estimate diagnoses given by board-certified psychiatrists. RESULTS: For most diagnoses and symptoms studied, as well as for most of the alcohol consumption measures, the test-retest reliability of the Spanish AUDADIS was consistent with results reported in other national and international studies using this instrument. Good to excellent test-retest reliability was obtained for the diagnoses of alcohol dependence and major depression. Similarly, good to excellent agreement was obtained between the lay administered AUDADIS and best estimate diagnoses for most diagnostic categories, with the exception of dysthymia. As in other studies, the reliability and validity of the substance abuse category was poor. When agreement for this category was estimated independent of lifetime dependence, both the reliability and validity coefficients were considerably improved. CONCLUSIONS: The Spanish AUDADIS generally demonstrates good to excellent levels of reliability and validity that are comparable to findings reported for this instrument in other national and international studies.


Asunto(s)
Alcoholismo/diagnóstico , Diagnóstico por Computador/estadística & datos numéricos , Hispánicos o Latinos/estadística & datos numéricos , Escalas de Valoración Psiquiátrica/estadística & datos numéricos , Adulto , Anciano , Alcoholismo/etnología , Alcoholismo/psicología , Comparación Transcultural , Femenino , Hispánicos o Latinos/psicología , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Psicometría , Puerto Rico/etnología , Reproducibilidad de los Resultados
7.
Dtsch Z Verdau Stoffwechselkr ; 39(2): 80-2, 1979.
Artículo en Alemán | MEDLINE | ID: mdl-156636

RESUMEN

Peritoneoscopy revealed in 15 patients with malignant lymphomas splenomegaly (13 patients), hepatomegaly (10 patients, 8 of them with impressive or suspicious alterations of the liver surface) and enlargement of retroperitoneal lymph nodes or localised infiltration of a jejunal loop (3 patients). Aimed biopsy of liver, spleen or lymph nodes frequently established the diagnosis definitively. The various features of malignant lymphomas observable at peritoneoscopy are described. Based on these experiences peritoneoscopy is recommended in suspected malignant lymphomas as a real diagnostic aid.


Asunto(s)
Laparoscopía , Linfoma/diagnóstico , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Retroperitoneales/diagnóstico , Neoplasias del Bazo/diagnóstico
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