Effects of a burst of formation of first-generation stars on the evolution of galaxies

First-generation (Population III) stars in the universe play an important role inearly enrichment of heavy elements in galaxies and intergalactic medium and thus affect the history of galaxies. The physical and chemical properties of primordial gas clouds are significantly different from those of present-day gas clouds observed in the nearby universe because the primordial gas clouds do not contain any heavy elements which are important coolants in the gas. Previous theoretical considerations have suggested that typical masses of the first-generation stars are between several $M_\odot$ and $\approx 10 M_\odot$ although it has been argued that the formation of very massive stars (e.g., $> 100 M_\odot$) is also likely. If stars with several $M_\odot$ are most popular ones at the epoch of galaxy formation, most stars will evolve to hot (e.g., $\gtrsim 10^5$ K), luminous ($\sim 10^4 L_\odot$) stars with gaseous and dusty envelope prior to going to die as white dwarf stars. Although the duration of this phase is short (e.g., $\sim 10^5$ yr), such evolved stars could contribute both to the ionization of gas in galaxies and to the production of a lot of dust grains if the formation of intermediate-mass stars is highly enhanced. We compare gaseous emission-line properties of such nebulae with some interesting high-redshift galaxies such asIRAS F10214+4724 and powerful radio galaxies.Comment: 25 pages, 7 figures, ApJ, in pres

A Shock-Induced Pair of Superbubbles in the High-Redshift Powerful Radio Galaxy MRC 0406-244

We present new optical spectroscopy of the high-redshift powerful radio galaxy MRC 0406$-$244 at redshift of 2.429. We find that the two extensions toward NW and SE probed in the rest-frame ultraviolet image are heated mainly by the nonthermal continuum of the active galactic nucleus. However, each extension shows a shell-like morphology, suggesting that they are a pair of superbubbles induced by the superwind activity rather than by the interaction between the radio jet and the ambient gas clouds. If this is the case, the intense starburst responsible for the formation of superbubbles could occur $\sim 1 \times 10^9$ yr ago. On the other hand, the age of the radio jets may be of the order of $\sim 10^6$ yr, being much shorter than the starburst age. Therefore, the two events, i.e., the starburst and the radio-jet activities, are independent phenomena. However, their directions of the expanding motions could be governed by the rotational motion of the gaseous component in the host galaxy. This idea appears to explain the alignment effect of MRC 0406$-$244.Comment: 4 pages (emulateapj.sty), Fig. 1 (jpeg) + Fig.2 (eps). Accepted for publications in ApJ (Letters

Use of parametric speaker for older people with dementia in a residential care setting: A preliminary study of two cases

Objective/Background Older people with dementia often show behavioural and psychological symptoms of dementia such as agitation, aggression, and depression that affect their activities of daily living, and hence reduce the quality of life of their caregivers. The aim of this study was to investigate the effects of a new technological intervention—a parametric speaker, creating a narrow personal acoustic environment, which may reduce the manifestation of behavioural and psychological symptoms of dementia symptoms. Methods A parametric speaker was placed on the ceiling of a large day room, and personally selected pieces of music were provided in a narrow space just under the speaker during the intervention. Two older residents with behavioural and psychological symptoms of dementia participated in the experiment. Results Playing pieces of favorite music via the parametric speaker decreased their behavioural and psychological symptoms of dementia during the intervention. In addition, this intervention reduced the burden on caregivers. One of the advantages of using parametric speaker was being able to create a personal space in a common room. Conclusion We considered that the parametric speaker might be useful to reduce behavioural and psychological symptoms of dementia and the burden on caregivers, providing individualized rehabilitation for the improved quality of life of residents

Assessment of time-related deficits in older adults : a scoping review protocol.

INTRODUCTION: People with cognitive impairments often have difficulties in managing their time for daily activities. In older adults with cognitive impairments such as dementia and stroke, these may present as disorientation, poor time awareness, time perception, daily time management and so on. Time-related deficits and associated behaviours impede independent living and add considerably to caregiver strain. Several interventions are being investigated to help people with cognitive impairments orient and navigate time and do their daily activities. The provision of interventions requires the use of sound assessment tools. However, it is not clear how time-related concepts are specifically evaluated in practice, what are the available assessments and how these assessments should be selected. METHOD AND ANALYSIS: This protocol follows the Joanna Briggs Institute Reviewer's Manual (2020) for scoping reviews and is registered with the Open Science Framework (https://osf.io/4ptgy/). We will include the following databases: PubMed, CINAHL, Scopus, Web of Science and PsycINFO. Two reviewers will independently screen eligible studies for inclusion against the selection criteria and then review the full-text of the selected studies. We will extract the bibliographic data, study design and setting, and details of assessments used in the studies to evaluate time-related concepts including format, mode and duration of administration, psychometric properties and so on. The identified assessments will be mapped with regard to time-related concepts being evaluated and described using narrative synthesis. ETHICS AND DISSEMINATION: As secondary data analysis, ethics approval is not required for this scoping review. We plan to disseminate the results through peer-reviewed journals and conferences targeting health professionals working with older adults