TRBP Research Articles

Comparative Analysis of a Transition Region Bright Point with a Blinker and Coronal Bright Point Using Multiple EIS Emission Lines

Since their discovery twenty year ago, transition region bright points (TRBPs) have never been observed spectroscopically. Bright point properties have not been compared with similar transition region and coronal structures. In this work we have investigated three transient quiet Sun brightenings including a TRBP, a coronal BP (CBP) and a blinker. We use time-series observations of the extreme ultraviolet emission lines of a wide range of temperature T (log T = 5.3 - 6.4) from the EUV imaging spectrometer (EIS) onboard the Hinode satellite. We present the EIS temperature maps and Doppler maps, which are compared with magnetograms from the Michelson Doppler Imager (MDI) onboard the SOHO satellite. Doppler velocities of the TR BP and blinker are <,25 km s$^{-1}$, which is typical of transient TR phenomena. The Dopper velocities of the CBP were found to be < 20 km s^{-1} with exception of those measured at log T = 6.2 where a distinct bi-directional jet is observed. From an EM loci analysis we find evidence of single and double isothermal components in the TRBP and CBP, respectively. TRBP and CBP loci curves are characterized by broad distributions suggesting the existence of unresolved structure. By comparing and contrasting the physical characteristics of the events we find the BP phenomena are an indication of multi-scaled self similarity, given similarities in both their underlying magnetic field configuration and evolution in relation to EUV flux changes. In contrast, the blinker phenomena and the TRBP are sufficiently dissimilar in their observed properties as to constitute different event classes. Our work indicates that the measurement of similar characteristics across multiple event types holds class-predictive power, and is a significant step towards automated solar atmospheric multi-class classification of unresolved transient EUV sources.

Predictors of insufficient response to initial antihypertensive treatment

To compare baseline central pulse wave characteristics in relation to response to initial antihypertensive treatment in previously untreated hypertensive patients. Design and methods. The study included 57 subjects (mean age 50,2 ± 13,7 years) with untreated arterial hypertension grade 1-2 without target organ damage on routine examination. Antihypertensive therapy was initiated after baseline ambulatory blood pressure monitoring (ABPM) and pulse wave analysis. Response to treatment was classified by joint evaluation of ABPM and clinic BP after 8 weeks of treatment. The baseline pulse wave velocity (PWV) was compared in 4 groups: 1) true responders (TR, normal clinic and ambulatory BP), 2) masked responders (MR, elevated clinic and normal ambulatory BP), 3) masked non-responders (MNR, normal clinic and elevated ambulatory BP), 4) true non-responders (TNR, elevated clinic and elevated ambulatory BP). Results. There were 21 (36,8 %) TR, 11 (19,3 %) MR, 11 (19,3 %) MNR, 14 (24,6 %) TNR. MNR was the youngest group but their baseline central systolic, pulse BP and PWV were at least similar or even higher than in the other groups. Conclusion. The results suggest that increased arterial stiffness may be responsible for insufficient response to initial antihypertensive treatment in non-diabetic hypertensive patients.