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1.
J Geophys Res Oceans ; 124(1): 403-431, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31007997

RESUMEN

Biogeochemical Argo floats, profiling to 2,000-m depth, are being deployed throughout the Southern Ocean by the Southern Ocean Carbon and Climate Observations and Modeling program (SOCCOM). The goal is 200 floats by 2020, to provide the first full set of annual cycles of carbon, oxygen, nitrate, and optical properties across multiple oceanographic regimes. Building from no prior coverage to a sparse array, deployments are based on prior knowledge of water mass properties, mean frontal locations, mean circulation and eddy variability, winds, air-sea heat/freshwater/carbon exchange, prior Argo trajectories, and float simulations in the Southern Ocean State Estimate and Hybrid Coordinate Ocean Model (HYCOM). Twelve floats deployed from the 2014-2015 Polarstern cruise from South Africa to Antarctica are used as a test case to evaluate the deployment strategy adopted for SOCCOM's 20 deployment cruises and 126 floats to date. After several years, these floats continue to represent the deployment zones targeted in advance: (1) Weddell Gyre sea ice zone, observing the Antarctic Slope Front, and a decadally-rare polynya over Maud Rise; (2) Antarctic Circumpolar Current (ACC) including the topographically steered Southern Zone chimney where upwelling carbon/nutrient-rich deep waters produce surprisingly large carbon dioxide outgassing; (3) Subantarctic and Subtropical zones between the ACC and Africa; and (4) Cape Basin. Argo floats and eddy-resolving HYCOM simulations were the best predictors of individual SOCCOM float pathways, with uncertainty after 2 years of order 1,000 km in the sea ice zone and more than double that in and north of the ACC.

2.
Ann Rev Mar Sci ; 8: 185-215, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26515811

RESUMEN

Global ship-based programs, with highly accurate, full water column physical and biogeochemical observations repeated decadally since the 1970s, provide a crucial resource for documenting ocean change. The ocean, a central component of Earth's climate system, is taking up most of Earth's excess anthropogenic heat, with about 19% of this excess in the abyssal ocean beneath 2,000 m, dominated by Southern Ocean warming. The ocean also has taken up about 27% of anthropogenic carbon, resulting in acidification of the upper ocean. Increased stratification has resulted in a decline in oxygen and increase in nutrients in the Northern Hemisphere thermocline and an expansion of tropical oxygen minimum zones. Southern Hemisphere thermocline oxygen increased in the 2000s owing to stronger wind forcing and ventilation. The most recent decade of global hydrography has mapped dissolved organic carbon, a large, bioactive reservoir, for the first time and quantified its contribution to export production (∼20%) and deep-ocean oxygen utilization. Ship-based measurements also show that vertical diffusivity increases from a minimum in the thermocline to a maximum within the bottom 1,500 m, shifting our physical paradigm of the ocean's overturning circulation.


Asunto(s)
Carbono/análisis , Agua de Mar/química , Clima , Oceanografía/instrumentación , Navíos , Temperatura , Movimientos del Agua
3.
Antimicrob Agents Chemother ; 50(7): 2409-14, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16801419

RESUMEN

Enteroviral meningitis causes appreciable morbidity in adults, including hospitalization, decreased activity, and headache. Limited data define the natural history of disease. No antiviral therapeutic agent has demonstrated improved outcome in controlled clinical trials. Pleconaril, an inhibitor of enterovirus replication, was tested in two placebo-controlled clinical trials. Of 607 randomized patients in a multicenter, double-blind placebo-controlled study of pleconaril (200 mg three times daily versus an identical-appearing placebo), 240 patients were confirmed to have enterovirus infection. The time to headache resolution was evaluated by using Kaplan-Meier survival methodology. A Cox regression model evaluated multivariate factors associated with disease resolution. Resolution of headache in patients with concomitant moderate to severe nausea at baseline occurred at a median of 9.5 days in the absence of therapy and was reduced to 7.0 days for pleconaril recipients (P = 0.009). For a headache score of > 5 alone, treated patients resolved headache significantly more rapidly (P = 0.005). Males resolved headache 50% faster than females. Regardless of randomization group, patients with a baseline headache score of 5 or greater resolved headache 50% more slowly than patients with a baseline headache score of 4. No differences in either clinical or laboratory adverse events were noted. Over 50% of untreated patients had a persistent headache that was greater than 1 week in duration. Pleconaril shortened the course of illness compared to placebo recipients, especially in the early disease course. However, the benefit was achieved only modestly in a subgroup analysis of patients with more severe disease after adjusting for confounding variables.


Asunto(s)
Antivirales/uso terapéutico , Infecciones por Enterovirus/tratamiento farmacológico , Infecciones por Enterovirus/fisiopatología , Cefalea/tratamiento farmacológico , Meningitis Viral/tratamiento farmacológico , Meningitis Viral/fisiopatología , Oxadiazoles/uso terapéutico , Adulto , Antivirales/administración & dosificación , Antivirales/efectos adversos , Método Doble Ciego , Infecciones por Enterovirus/virología , Femenino , Cefalea/virología , Humanos , Masculino , Meningitis Viral/virología , Análisis Multivariante , Oxadiazoles/administración & dosificación , Oxadiazoles/efectos adversos , Oxazoles , Resultado del Tratamiento
4.
Biotech Histochem ; 78(1): 17-21, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12713137

RESUMEN

Dimethylsulfoxide (DMSO) is a well-known solvent that is commonly used in the laboratory. We selected DMSO as the vehicle for an experiment designed to determine if several nonsteroidal anti-inflammatory agents inhibit the growth of Caov-3, OVCAR-3, and SK-OV-3 ovarian carcinoma cell lines. Using the tetrazolium conversion assay, however, we observed some variability in the number of cells present in each ovarian carcinoma cell line with varying concentrations of DMSO (10(-6)-10(-2) M) compared to medium alone. Similarly, when Caov-3, OVCAR-3, and SK-OV-3 cells were treated with 10(-4) M DMSO plus medium (Dulbecco's Modified Eagle Medium with 10% fetal bovine serum) and plated on coverslips, the total number of cells present in 60 random fields increased significantly (P < 0.0001) for each ovarian carcinoma cell line treated with DMSO compared to medium alone. Ethanol did not demonstrate such prominent effects on cellular growth. Our observations are important to consider when selecting an appropriate solvent, especially for growth inhibition studies using Caov-3, OVCAR-3, and SK-OV-3 cell lines.


Asunto(s)
Acetaminofén/farmacología , Aspirina/farmacología , Técnicas de Cultivo de Célula/métodos , Medios de Cultivo/farmacología , Dimetilsulfóxido/farmacología , Etanol/farmacología , Neoplasias Ováricas/patología , Recuento de Células , División Celular/efectos de los fármacos , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Sensibilidad y Especificidad
5.
Science ; 299(5615): 2005-10, 2003 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-12663908

RESUMEN

Large, abrupt, and widespread climate changes with major impacts have occurred repeatedly in the past, when the Earth system was forced across thresholds. Although abrupt climate changes can occur for many reasons, it is conceivable that human forcing of climate change is increasing the probability of large, abrupt events. Were such an event to recur, the economic and ecological impacts could be large and potentially serious. Unpredictability exhibited near climate thresholds in simple models shows that some uncertainty will always be associated with projections. In light of these uncertainties, policy-makers should consider expanding research into abrupt climate change, improving monitoring systems, and taking actions designed to enhance the adaptability and resilience of ecosystems and economies.

6.
JAMA ; 286(5): 563-71, 2001 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-11476658

RESUMEN

CONTEXT: The World Food Programme estimated that 10 million people were at risk of starvation in Ethiopia in 2000 but later reported that a famine had been averted. However, no population-based data on mortality or nutrition existed for Gode district, at the epicenter of the famine in the Somali region of Ethiopia. OBJECTIVES: To estimate mortality rates, determine the major causes of death, and estimate the prevalence of malnutrition among children and adults for the population of Gode district. DESIGN AND SETTING: Two-stage cluster survey conducted from July 27 through August 1, 2000, which included anthropometric measures and 8-month retrospective mortality data collection. PARTICIPANTS: A total of 595 households comprising 4032 people living in Gode district of Ethiopia. MAIN OUTCOME MEASURES: Crude mortality rates and mortality rates for children younger than 5 years, causes of death, weight for height of less than -2 z scores among children aged 6 months to 5 years, and body mass index of less than 18.5 kg/m(2) among adults and older persons. RESULTS: Of the 595 households, 346 (58.2%) were displaced from their usual places of residence. From December 1999 through July 2000, a total of 293 deaths occurred in the sample population; 159 (54.3%) deaths were among children younger than 5 years and 72 (24.6%) were among children aged 5 to 14 years. The crude mortality rate was 3.2/10 000 per day (95% confidence interval [CI], 2.4-3.8/10 000 per day), which is 3 times the cutoff used to define an emergency. The mortality rate for children younger than 5 years was 6.8/10 000 per day (95% CI, 5.4-8.2/10 000 per day). Approximately 77% of deaths occurred before major relief interventions began in April/May 2000. Wasting contributed to 72.3% of all deaths among children younger than 5 years. Measles alone or in combination with wasting accounted for 35 (22.0%) of 159 deaths among children younger than 5 years and for 12 (16.7%) of 72 deaths among children aged 5 to 14 years. The prevalence rate for wasting (weight for height of <-2 z score) among children aged 6 months to 5 years was 29.1% (95% CI, 24.7%-33.4%). Using a method to adjust body mass index for body shape, the prevalence of undernutrition (body mass index <18.5 kg/m(2)) among adults aged 18 to 59 years was 22.7% (95% CI, 17.9%-27.5%). CONCLUSIONS: To prevent unnecessary deaths, the humanitarian response to famine needs to be rapid, well coordinated, and based on sound epidemiological evidence. Public health interventions, such as mass measles vaccination campaigns with coverage extended to children aged 12 to 15 years should be implemented as the first priority. The prevalence of wasting and undernutrition among children and adults, respectively, should be assessed in all prolonged, severe famines.


Asunto(s)
Sarampión/epidemiología , Trastornos Nutricionales/epidemiología , Inanición/complicaciones , Inanición/mortalidad , Adolescente , Adulto , Índice de Masa Corporal , Causas de Muerte , Niño , Preescolar , Etiopía/epidemiología , Humanos , Lactante , Persona de Mediana Edad , Morbilidad , Sistemas de Socorro
7.
J Clin Epidemiol ; 51(10): 853-7, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9762878

RESUMEN

The controversy over whether melanoma of the foot has a poorer prognosis than melanoma of the leg remains unresolved. This investigation used a case-control design to address this issue. This design consisted of a survival analysis of 119 cases with localized melanoma of the foot and 238 controls with localized melanoma of the leg that were matched on prognostic factors including tumor thickness, ulceration, surgical treatment, gender, year of diagnosis, and age. There was a statistically significant difference between the survival rates of cases and controls. The 5-year survival rate for cases was 74.3% compared to 85.2% for controls. At 10 years, the survival rate was 63.6% for cases and 77.2% for controls. Cases experienced a higher percentage of distant recurrences than controls. These results imply that patients with melanoma of the foot have a poorer survival than patients with melanoma of the leg after controlling for prognostic factors.


Asunto(s)
Enfermedades del Pie/terapia , Pierna , Melanoma/terapia , Neoplasias Cutáneas/terapia , Adulto , Anciano , Femenino , Enfermedades del Pie/mortalidad , Enfermedades del Pie/patología , Humanos , Masculino , Melanoma/mortalidad , Melanoma/patología , Persona de Mediana Edad , Análisis Multivariante , Estadificación de Neoplasias , Pronóstico , Modelos de Riesgos Proporcionales , Neoplasias Cutáneas/mortalidad , Neoplasias Cutáneas/patología , Análisis de Supervivencia , Resultado del Tratamiento
8.
9.
J Am Acad Audiol ; 7(6): 419-27, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8972443

RESUMEN

The present study examined the performance of 40 normal-hearing young adults and 38 elderly adults, some normal hearing and some hearing impaired, on the Department of Veterans Affairs' new compact disc (VA-CD) for auditory perceptual assessment. Principal-components factor analyses were performed on the test scores from each group of subjects with very similar results obtained from each group in terms of the number of factors identified (3), the percentage of variance explained by these factors individually and collectively (about 72%), and the association of various test scores with each factor. The 10 tests examined here were found to be associated with three underlying factors identified as a general speech-understanding ability (about 42% of variance), temporal sequencing capacity (about 18% of variance), and processing ability under conditions of dichotic competition (about 12% of variance). Among the elderly, hearing loss was strongly and negatively associated with general speech-recognition ability, whereas age was moderately associated with the other two factors. Test scores for several measures of auditory perceptual processing were negatively affected by the presence of peripheral hearing loss in the elderly even when administered at the highest recommended presentation level (90 dB SPL). In addition, some tests among those examined were found to have inadequate test-retest reliability for clinical use with the elderly.


Asunto(s)
Envejecimiento , Discos Compactos , Percepción del Habla , Adolescente , Adulto , Anciano , Audiometría de Tonos Puros , Pruebas de Audición Dicótica , Humanos , Persona de Mediana Edad , Pruebas de Discriminación del Habla
10.
Rehabil Nurs ; 19(6): 355-8, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7855404

RESUMEN

In this article, the authors describe how the needs of the patient with a new amputation were assessed and how behavioral objectives were developed for an educational program that would address the knowledge, motor skills, and attitudes necessary for self-care. Two teaching techniques are described. An evaluation process that identifies the patient's or family's achievement of the objectives is discussed.


Asunto(s)
Amputados/rehabilitación , Educación del Paciente como Asunto/métodos , Desarrollo de Programa , Conocimientos, Actitudes y Práctica en Salud , Humanos , Enseñanza/métodos
11.
Science ; 263(5150): 1125-8, 1994 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-17831626

RESUMEN

Large-scale, westward-extending tongues of warm (Pacific) and cold (Atlantic) water are found between 2000 and 3000 meters both north and south of the equator in the Pacific and Atlantic oceans. They are centered at 5 degrees to 8 degrees north and 10 degrees to 15 degrees south (Pacific) and 5 degrees to 8 degrees north and 15 degrees to 20 degrees south (Atlantic). They are separated in both oceans by a contrasting eastward-extending tongue, centered at about 1 degrees to 2 degrees south, in agreement with previous helium isotope observations (Pacific). Thus, the indicated deep tropical westward flows north and south of the equator and eastward flow near the equator may result from more general forcing than the hydrothermal forcing previously hypothesized.

12.
Appl Opt ; 17(23)1978 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-20208587
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