738 research outputs found
Filament eruption connected to protospheric activity
Two cases of activation of filaments that occured in regions of intense magnetic activity was studied. The simultaneous observations from Debrecen Observatory (white light and H alpha filtergram), and from Meudon Observatory (magnetogram, MSDP dopplergram and intensity maps in H alpha) gave a complementary set of data from which can be produced evidence of the influence of the photospheric magnetic field on the destabilization process of the filaments. On June 22, 1980, the eruption of the filament is associated with the motion of pores, which are manifestations of emerging flux knots. On September 3, 1980, the twisting motions in the filament are associated to the birth of a pore in its neighborhood. These observations are discussed
Pathways to early retirement: structure and agency in decision-making among British civil servants
The effects of pre-retirement factors and retirement route on circumstances in retirement: findings from the Whitehall II study
Retirement has traditionally been seen as the beginning of old age. It has been depicted as mandatory expulsion from the workforce and seen to mark the transition to a period of ill health and poverty. Such ideas and associations are however being challenged in the developed world by socio-demographic changes in retirement and old age. People in the United Kingdom as elsewhere are living longer and healthier lives, and many older people have access to non-state incomes that afford them a reasonable standard of living in retirement. There is however still concern that inequalities persist into old age. Data from two waves of the British Whitehall II study have been used to assess the relative effects of occupational grade, psychological and general health during working life, and retirement patterns or pathways on activities, attitudes to health and income in retirement. The results show that the majority of the sample reported good health, financial security and overall satisfaction with life, but with observable inequalities. Regression analyses demonstrate that pre-retirement circumstances generally had a greater effect on later life than the retirement route or pathway. Retirement no longer represents a drastic break between working and post-work life but rather, the results suggest, there are continuities between the two periods. It is concluded that the main causes of inequalities in retirement are work-based rather than in retirement itself
The solar chromosphere at high resolution with IBIS. I. New insights from the Ca II 854.2 nm line
(Abridged)
Aims: In this paper, we seek to establish the suitability of imaging
spectroscopy performed in the Ca II 854.2 nm line as a means to investigate the
solar chromosphere at high resolution.
Methods: We utilize monochromatic images obtained with the Interferometric
BIdimensional Spectrometer (IBIS) at multiple wavelengths within the Ca II
854.2 nm line and over several quiet areas. We analyze both the morphological
properties derived from narrow-band monochromatic images and the average
spectral properties of distinct solar features such as network points,
internetwork areas and fibrils.
Results: The spectral properties derived over quiet-Sun targets are in full
agreement with earlier results obtained with fixed-slit spectrographic
observations, highlighting the reliability of the spectral information obtained
with IBIS. Furthermore, the very narrowband IBIS imaging reveals with much
clarity the dual nature of the Ca II 854.2 nm line: its outer wings gradually
sample the solar photosphere, while the core is a purely chromospheric
indicator. The latter displays a wealth of fine structures including bright
points, akin to the Ca II H2V and K2V grains, as well as fibrils originating
from even the smallest magnetic elements. The fibrils occupy a large fraction
of the observed field of view even in the quiet regions, and clearly outline
atmospheric volumes with different dynamical properties, strongly dependent on
the local magnetic topology. This highlights the fact that 1-D models
stratified along the vertical direction can provide only a very limited
representation of the actual chromospheric physics.Comment: 13 pages, 8 figures. Accepted in A&A. Revised version after referee's
comments. New Fig. 1 and 7. Higher quality figures in
http://www.arcetri.astro.it/~gcauzzi/papers/ibis.caii.pd
Estimation of solar prominence magnetic fields based on the reconstructed 3D trajectories of prominence knots
We present an estimation of the lower limits of local magnetic fields in
quiescent, activated, and active (surges) promineces, based on reconstructed
3-dimensional (3D) trajectories of individual prominence knots. The 3D
trajectories, velocities, tangential and centripetal accelerations of the knots
were reconstructed using observational data collected with a single
ground-based telescope equipped with a Multi-channel Subtractive Double Pass
imaging spectrograph. Lower limits of magnetic fields channeling observed
plasma flows were estimated under assumption of the equipartition principle.
Assuming approximate electron densities of the plasma n_e = 5*10^{11} cm^{-3}
in surges and n_e = 5*10^{10} cm^{-3} in quiescent/activated prominences, we
found that the magnetic fields channeling two observed surges range from 16 to
40 Gauss, while in quiescent and activated prominences they were less than 10
Gauss. Our results are consistent with previous detections of weak local
magnetic fields in the solar prominences.Comment: 14 pages, 12 figures, 1 tabl
3D evolution of a filament disappearance event observed by STEREO
A filament disappearance event was observed on 22 May 2008 during our recent
campaign JOP 178. The filament, situated in the southern hemisphere, showed
sinistral chirality consistent with the hemispheric rule. The event was well
observed by several observatories in particular by THEMIS. One day before the
disappearance, H observations showed up and down flows in adjacent
locations along the filament, which suggest plasma motions along twisted flux
rope. THEMIS and GONG observations show shearing photospheric motions leading
to magnetic flux canceling around barbs. STEREO A, B spacecraft with separation
angle 52.4 degrees, showed quite different views of this untwisting flux rope
in He II 304 \AA\ images. Here, we reconstruct the 3D geometry of the filament
during its eruption phase using STEREO EUV He II 304 \AA\ images and find that
the filament was highly inclined to the solar normal. The He II 304 \AA\ movies
show individual threads, which oscillate and rise to an altitude of about 120
Mm with apparent velocities of about 100 km s, during the rapid
evolution phase. Finally, as the flux rope expands into the corona, the
filament disappears by becoming optically thin to undetectable levels. No CME
was detected by STEREO, only a faint CME was recorded by LASCO at the beginning
of the disappearance phase at 02:00 UT, which could be due to partial filament
eruption. Further, STEREO Fe XII 195 \AA\ images showed bright loops beneath
the filament prior to the disappearance phase, suggesting magnetic reconnection
below the flux rope
Retirement and Socioeconomic Differences in Diurnal Cortisol: Longitudinal Evidence From a Cohort of British Civil Servants
Objectives: Early old age and the period around retirement are associated with a widening in socioeconomic inequalities in health. There are few studies that address the stress-biological factors related to this widening. This study examined whether retirement is associated with more advantageous (steeper) diurnal cortisol profiles, and differences in this association by occupational grade.
Method: Data from the 7th (2002–2004), 8th (2006), and 9th (2007–09) phases of the London-based Whitehall II civil servants study were analysed. Thousand hundred and forty three respondents who were employed at phase 8 (mean age 59.9 years) and who had salivary cortisol measured from five samples collected across the day at phases 7 and 9 were analysed.
Results: Retirement was associated with steeper diurnal slopes compared to those who remained in work. Employees in the lowest grades had flatter diurnal cortisol slopes compared to those in the highest grades. Low-grade retirees in particular had flatter diurnal slopes compared to high-grade retirees.
Discussion: Socioeconomic differences in a biomarker associated with stress increase, rather than decrease, around the retirement period. These biological differences associated with transitions into retirement for different occupational groups may partly explain the pattern of widening social inequalities in health in early old age
Qualitative focus group study investigating experiences of accessing and engaging with social care services: perspectives of carers from diverse ethnic groups caring for stroke survivors
OBJECTIVES:
Informal carers, often family members, play a vital role in supporting stroke survivors with post-stroke disability. As populations age, numbers of carers overall and those from minority ethnic groups in particular, are rising. Carers from all ethnic groups, but especially those from black and minority ethnic groups frequently fail to access support services, making understanding their experiences important. The study therefore explored the experiences of carers of stroke survivors aged 45+ years from 5 ethnic groups in accessing and receiving social care services after hospital discharge.
DESIGN:
This qualitative study used 7 recorded focus groups with informal carers of stroke survivors. Data were analysed thematically focusing on similarities and differences between ethnic groups.
SETTING:
Carers were recruited from voluntary sector organisations supporting carers, stroke survivors and black and minority ethnic groups in the UK.
PARTICIPANTS:
41 carers from 5 ethnic groups (Asian Indian, Asian Pakistani, black African, black Caribbean, white British) participated in the focus groups.
RESULTS:
Several interconnected themes were identified including: the service gap between hospital discharge and home; carers as the best person to care and cultural aspects of caring and using services. Many themes were common to all the included ethnic groups but some related to specific groups.
CONCLUSIONS:
Across ethnic groups there were many similarities in the experiences of people caring for stroke survivors with complex, long-term care needs. Accessing services demands effort and persistence on carers' part. If carers believe services are unsatisfactory or that they, rather than formal services, should be providing support for stroke survivors, they are unlikely to persist in their efforts. Cultural and language differences add to the challenges black and minority ethnic group carers face
A cross-sectional exploratory analysis between pet ownership and sleep, exercise, health and neighborhood perceptions : The Whitehall II cohort study
A cross-sectional exploratory analysis between pet ownership and sleep, exercise, health and neighbourhood perceptions: The Whitehall II cohort study
Gill Mein (corresponding author), Robert Grant. Faculty of Health, Social Care and Education. Kingston University and St George’s University of London
Background: To explore associations between pets, and specifically dog ownership and sleep, health, exercise and neighbourhood.
Methods: Cross sectional examination of 6575 participants of the Whitehall II study aged between 59-79 years. We used self-assessed measurement scales of the Short Form (SF36), General Health Questionnaire (GHQ), Control, Autonomy, Self-realisation and Pleasure (CASP), Centre for Epidemiologic Studies Depression Scale (CES-D), sleep, exercise, and perceptions of local neighbourhood. In addition the Mini Mental State Examination which is administered to test global cognitive status (MMSE)
Results: We found 2/7 people owned a pet and of those 64% were “very” attached to their pet. Mild exercise in metabolic equivalents (MET-hours) was significantly higher in pet owners than non-owners (median 27.8 (IQR 18.1 to 41.8) vs 25.7 (IQR 16.8 to 38.7), p=0.0001), and in dog owners than other pets (median 32.3 (IQR 20.8 to 46.1) vs 25.6 (IQR 16.8 to 38.5), p<0.0001). Moderate exercise was also significantly higher in pet owners than non pet owners (median 11.8 (IQR 4.2 to 21.9) vs 9.8 (IQR 2.8 to 19.5), p<0.0001), and dog owners than owners of other pets (median 12.3 (IQR 4.2 to 22.2) vs 10.1 (3.1 to 20.0), p=0.0002) but there were no significant differences with vigorous exercise. We found that pet owners were significantly more positive about their neighbourhood than non-owners on 8/9 questions, while dog owners were (significantly) even more positive than owners of other pets on 8/9 questions. Associations with sleep were mixed, although dog owners had less trouble falling asleep than non-dog owners, with borderline statistical significance.
Conclusion: Dog owners feel more positive about their neighbourhood, do more exercise, and fall asleep more easily than non-dog owners. These results suggest that dog owners could be more likely to exercise by walking their dogs and therefore may be more familiar and positive about the area in which they walk their dog
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