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1.
Science ; 243(4887): 57-63, 1989 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-17780422

RESUMEN

The study of climate and climate change is hindered by a lack of information on the effect of clouds on the radiation balance of the earth, referred to as the cloud-radiative forcing. Quantitative estimates of the global distributions of cloud-radiative forcing have been obtained from the spaceborne Earth Radiation Budget Experiment (ERBE) launched in 1984. For the April 1985 period, the global shortwave cloud forcing [-44.5 watts per square meter (W/m(2))] due to the enhancement of planetary albedo, exceeded in magnitude the longwave cloud forcing (31.3 W/m(2)) resulting from the greenhouse effect of clouds. Thus, clouds had a net cooling effect on the earth. This cooling effect is large over the mid-and high-latitude oceans, with values reaching -100 W/m(2). The monthly averaged longwave cloud forcing reached maximum values of 50 to 100 W/m(2) over the convectively disturbed regions of the tropics. However, this heating effect is nearly canceled by a correspondingly large negative shortwave cloud forcing, which indicates the delicately balanced state of the tropics. The size of the observed net cloud forcing is about four times as large as the expected value of radiative forcing from a doubling of CO(2). The shortwave and longwave components of cloud forcing are about ten times as large as those for a CO(2) doubling. Hence, small changes in the cloud-radiative forcing fields can play a significant role as a climate feedback mechanism. For example, during past glaciations a migration toward the equator of the field of strong, negative cloud-radiative forcing, in response to a similar migration of cooler waters, could have significantly amplified oceanic cooling and continental glaciation.

2.
Science ; 259(5100): 1411-5, 1993 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-17801273

RESUMEN

Radiative flux anomalies derived from the National Aeronautics and Space Administration (NASA) spaceborne Earth Radiation Budget Experiment were used to determine the volcanic radiative forcing that followed the eruption of Mount Pinatubo in June 1991. They are the first unambiguous, direct measurements of large-scale volcanic forcing. The volcanic aerosols caused a strong cooling effect immediately; the amount of cooling increased through September 1991 as shortwave forcing increased relative to the longwave forcing. The primary effects of the aerosols were a direct increase in albedo over mostly clear areas and both direct and indirect increases in the albedo of cloudy areas.

3.
Science ; 267(5197): 496-9, 1995 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-17788783

RESUMEN

There has been a long history of unexplained anomalous absorption of solar radiation by clouds. Collocated satellite and surface measurements of solar radiation at five geographically diverse locations showed significant solar absorption by clouds, resulting in about 25 watts per square meter more global-mean absorption by the cloudy atmosphere than predicted by theoretical models. It has often been suggested that tropospheric aerosols could increase cloud absorption. But these aerosols are temporally and spatially heterogeneous, whereas the observed cloud absorption is remarkably invariant with respect to season and location. Although its physical cause is unknown, enhanced cloud absorption substantially alters our understanding of the atmosphere's energy budget.

4.
Respir Med Case Rep ; 18: 90-2, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27330962

RESUMEN

Birt-Hogg-Dubé syndrome, initially described in 1977, is an autosomal dominant inherited condition characterised by basal pulmonary cysts often resulting in pneumothorax, renal tumours and cutaneous involvement. Lung cysts have been described in up to 90% of patients with a corresponding risk of pneumothorax of 50 times greater than the normal population. We describe here a case of Birt-Hogg-Dubé diagnosed in the 9th decade of life and discuss the radiological findings and clinical implications.

5.
Ir J Med Sci ; 185(4): 969-971, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26428728

RESUMEN

BACKGROUND: Ireland has one of the highest prevalence of sarcoidosis globally. Currently anti-TNF treatment in sarcoidosis is considered on a case-by-case basis particularly in patients who have a sub-optimal response to corticosteroid therapy. AIMS: We report our experience of Adalimumab in a series of refractory pulmonary sarcoidosis and discuss implications for treatment. CONCLUSION: Symptomatic improvement was found in all patients as well as stabilisation or improvement in DLCO sb. Improvements in pulmonary function tests correlated well to radiological stage and length of disease.


Asunto(s)
Adalimumab/uso terapéutico , Productos Biológicos/uso terapéutico , Fármacos del Sistema Respiratorio/uso terapéutico , Sarcoidosis Pulmonar/tratamiento farmacológico , Adulto , Enfermedad Crónica , Femenino , Humanos , Irlanda , Masculino , Persona de Mediana Edad , Pruebas de Función Respiratoria , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores
6.
Science ; 339(6120): 647, 2013 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-23393247

RESUMEN

Bourassa et al. (Reports, 6 July 2012, p. 78) have suggested that deep convection associated with the Asian monsoon played a critical role in transporting sulfur dioxide associated with the Nabro volcanic eruption (13 June 2011) from the upper troposphere (9 to 14 kilometers) into the lower stratosphere. An analysis of the CALIPSO lidar data indicates, however, that the main part of the Nabro volcanic plume was injected directly into the lower stratosphere during the initial eruption well before reaching the Asian monsoon deep convective region.

7.
9.
Am J Phys Anthropol ; 43(1): 19-22, 1975 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1155588

RESUMEN

Intr-individual correlations for cranial, mandibular and dental measurements made on lateral skull radiographs of Macaca nemestrina were systematically higher in 30 adult females than in 31 adult males by an average of 0.11 to 0.15, depending upon method of computation. Clearly, for the adult pig-tailed monkey as in Homo during both prenatal and postnatal life, developmental and dimensional communalities are systematically higher in the female indicating a general principle or trend.


Asunto(s)
Macaca/anatomía & histología , Cráneo/anatomía & histología , Animales , Femenino , Humanos , Masculino , Mandíbula/anatomía & histología , Radiografía , Cromosomas Sexuales , Factores Sexuales , Cráneo/diagnóstico por imagen , Diente/anatomía & histología
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