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1.
Sci Adv ; 7(8)2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33608278

RESUMEN

Routine ultraviolet imaging of the Sun's upper atmosphere shows the spectacular manifestation of solar activity; yet, we remain blind to its main driver, the magnetic field. Here, we report unprecedented spectropolarimetric observations of an active region plage and its surrounding enhanced network, showing circular polarization in ultraviolet (Mg ii h & k and Mn i) and visible (Fe i) lines. We infer the longitudinal magnetic field from the photosphere to the very upper chromosphere. At the top of the plage chromosphere, the field strengths reach more than 300 G, strongly correlated with the Mg ii k line core intensity and the electron pressure. This unique mapping shows how the magnetic field couples the different atmospheric layers and reveals the magnetic origin of the heating in the plage chromosphere.

2.
Appl Opt ; 54(8): 2080-4, 2015 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-25968386

RESUMEN

Precise polarization measurements in the vacuum ultraviolet (VUV) region provide a new means for inferring weak magnetic fields in the upper atmosphere of the Sun and stars. We propose a VUV spectropolarimeter design ideally suited for this purpose. This design is proposed and adopted for the NASA-JAXA chromospheric lyman-alpha spectropolarimeter (CLASP), which will record the linear polarization (Stokes Q and U) of the hydrogen Lyman-α line (121.567 nm) profile. The expected degree of polarization is on the order of 0.1%. Our spectropolarimeter has two optically symmetric channels to simultaneously measure orthogonal linear polarization states with a single concave diffraction grating that serves both as the spectral dispersion element and beam splitter. This design has a minimal number of reflective components with a high VUV throughput. Consequently, these design features allow us to minimize the polarization errors caused by possible time variation of the VUV flux during the polarization modulation and by statistical photon noise.

3.
Women Health ; 39(2): 83-96, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15130863

RESUMEN

An exploratory study of 26 female urban, street-level sex workers was conducted to gather information about their health problems, feelings of stigmatizations, satisfaction with life, and literacy skills. Each woman completed the health questionnaire, Stigmatization Scale, Satisfaction with Life Scale, and the Rapid Estimate of Adult Literacy in Medicine. Twenty-one women had acute or chronic health problems; only eleven sought health care. Literacy scores revealed 7th to 8th grade reading levels. Feelings of stigmatization varied from low to high and all the women were found to be dissatisfied with their lives. Further research needs to address how these factors affect their use of health care and outreach services.


Asunto(s)
Escolaridad , Indicadores de Salud , Satisfacción Personal , Prejuicio , Trabajo Sexual/psicología , Población Urbana , Femenino , Humanos , Encuestas y Cuestionarios
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