title: Interstellar neutral hydrogen in the heliosphere: new horizons observations in the context of models

authors: Swaczyna, P

subjects: mathematics

abstract: Interstellar neutral (ISN) hydrogen is the most abundant species in the outer heliosheath and the very local interstellar medium (VLISM). Charge-exchange collisions in the outer heliosheath result in filtration, reducing the ISN hydrogen density inside the heliosphere. Additionally, these atoms are intensively ionized close to the Sun, resulting in a substantial reduction of their density within a few astronomical units from the Sun. The products of this ionization—pickup ions (PUIs)—are detected by charged particle detectors. The Solar Wind Around Pluto instrument on New Horizons provides, for the first time, PUI observations from the distant heliosphere. We analyze the observations collected between 22 and 52 au from the Sun to find the ISN hydrogen density profile and compare the results with predictions from global heliosphere models. We conclude that the density profile derived from the observations is inconsistent with steady-state model predictions. This discrepancy is not explained by time variations close to the Sun and thus may be related to the temporal evolution of the outer boundaries or VLISM conditions. Furthermore, we show that the cold and hot models of ISN hydrogen distribution are not a good approximation closer to the termination shock. Therefore, we recommend a new fiduciary point based on the available New Horizons observations at 40 au from the Sun, at ecliptic direction (285.°62, 1.°94), where the ISN hydrogen density is 0.11 cm−3. The continued operation of New Horizons should give better insight into the source of the discussed discrepancy.

text: Interstellar neutral hydrogen in the heliosphere: new horizons observations in the context of models Interstellar neutral (ISN) hydrogen is the most abundant species in the outer heliosheath and the very local interstellar medium (VLISM). Charge-exchange collisions in the outer heliosheath result in filtration, reducing the ISN hydrogen density inside the heliosphere. Additionally, these atoms are intensively ionized close to the Sun, resulting in a substantial reduction of their density within a few astronomical units from the Sun. The products of this ionization—pickup ions (PUIs)—are detected by charged particle detectors. The Solar Wind Around Pluto instrument on New Horizons provides, for the first time, PUI observations from the distant heliosphere. We analyze the observations collected between 22 and 52 au from the Sun to find the ISN hydrogen density profile and compare the results with predictions from global heliosphere models. We conclude that the density profile derived from the observations is inconsistent with steady-state model predictions. This discrepancy is not explained by time variations close to the Sun and thus may be related to the temporal evolution of the outer boundaries or VLISM conditions. Furthermore, we show that the cold and hot models of ISN hydrogen distribution are not a good approximation closer to the termination shock. Therefore, we recommend a new fiduciary point based on the available New Horizons observations at 40 au from the Sun, at ecliptic direction (285.°62, 1.°94), where the ISN hydrogen density is 0.11 cm−3. The continued operation of New Horizons should give better insight into the source of the discussed discrepancy.

year: 2024

title: A case for examining the social context of frailty in later life

authors: Barrett, Patrick

subjects: frailty

abstract: This paper makes a case for examining late life frailty as a dynamic social phenomenon. There is increasing interest in the issue of late life frailty from biomedical researchers, but less so from researchers using the perspectives and methods of social gerontology given a concern that to focus on aspects of functional decline tacitly endorses negative views of ageing. This paper begins by introducing an example of the way frailty in older people is referred to in regional health policy initiatives in New Zealand, before discussing issues around the definition of frailty and its significance. It concludes by noting that, while the term frailty is problematic, social gerontology has a contribution to make in understanding processes of loss of capacity in later life and the social and institutional context within which that occurs, and thus has a contribution to make in policy planning and service delivery.

text: A case for examining the social context of frailty in later life This paper makes a case for examining late life frailty as a dynamic social phenomenon. There is increasing interest in the issue of late life frailty from biomedical researchers, but less so from researchers using the perspectives and methods of social gerontology given a concern that to focus on aspects of functional decline tacitly endorses negative views of ageing. This paper begins by introducing an example of the way frailty in older people is referred to in regional health policy initiatives in New Zealand, before discussing issues around the definition of frailty and its significance. It concludes by noting that, while the term frailty is problematic, social gerontology has a contribution to make in understanding processes of loss of capacity in later life and the social and institutional context within which that occurs, and thus has a contribution to make in policy planning and service delivery.

year: 2006

title: Observations by and conversations with health workers and hospital personnel involved in transferring Maori patients and whānau to Waikato Hospital in Aotearoa New Zealand

authors: Masters-Awatere, Bridgette

subjects: Science & Technology

abstract: The predominant focus of Aotearoa New Zealand’s public health system on biomedical models of health has left little room for meaningful engagement with holistic indigenous approaches. Culturally appropriate provision and support are recognized for their relevance and importance during hospital transferals. Hospital staff involved in transfers to one of New Zealand’s trauma centers share their observations of whānau Māori engagement during an admission away from their home base. Sixteen key informants share their experiences, which are presented as strategies and challenges to whānau engagement. Three main themes highlight challenges within the health system that make it difficult for hospital staff to engage whānau in the desired ways and as often as both parties would like. Key informants described services and practices that are not designed with patients and their whānau in mind; instead they are designed by clinicians around the needs of administrative systems. As employees within the public health system, key informants felt powerless to challenge dominant settings. Nevertheless, employees managed to circumnavigate processes. Our findings highlight the need for continued decolonization and anti-racism work within public health settings.

text: Observations by and conversations with health workers and hospital personnel involved in transferring Maori patients and whānau to Waikato Hospital in Aotearoa New Zealand The predominant focus of Aotearoa New Zealand’s public health system on biomedical models of health has left little room for meaningful engagement with holistic indigenous approaches. Culturally appropriate provision and support are recognized for their relevance and importance during hospital transferals. Hospital staff involved in transfers to one of New Zealand’s trauma centers share their observations of whānau Māori engagement during an admission away from their home base. Sixteen key informants share their experiences, which are presented as strategies and challenges to whānau engagement. Three main themes highlight challenges within the health system that make it difficult for hospital staff to engage whānau in the desired ways and as often as both parties would like. Key informants described services and practices that are not designed with patients and their whānau in mind; instead they are designed by clinicians around the needs of administrative systems. As employees within the public health system, key informants felt powerless to challenge dominant settings. Nevertheless, employees managed to circumnavigate processes. Our findings highlight the need for continued decolonization and anti-racism work within public health settings.

year: 2020