Relaxation of an electron system: Conserving approximation

The dynamic response of an interacting electron system is determined by an extension of the relaxation-time approximation forced to obey local conservation laws for number, momentum and energy. A consequence of these imposed constraints is that the local electron equilibrium distribution must have a space- and time-dependent chemical potential, drift velocity and temperature. Both quantum kinetic and semi-classical arguments are given, and we calculate and analyze the corresponding analytical d-dimensional dielectric function. Dynamical correlation, arising from relaxation effects, is shown to soften the plasmon dispersion of both two- and three-dimensional systems. Finally, we consider the consequences for a hydrodynamic theory of a d-dimensional interacting electron gas, and by incorporating the competition between relaxation and inertial effects we derive generalised hydrodynamic equations applicable to arbitrary frequencies

Effect of food and temperature on the development and silk production of Bombyx mori Linnaeus (Lepidoptera: Bombycidae).

Larven von Bombyx mori Linnaeus wurden mit verschiedenartiger Nahrung bei unterschiedlichen Temperaturen aufgezogen. Es wurde festgestellt, daß die Entwicklung bei 30°C am schnellsten und bei 20°C am langsamsten verlief, daß aber die ausgereiften Larven und Puppen bei 25°C am meisten wogen. Der Wassergehalt der gezogenen Puppen war bei 20°C höher als bei den beiden anderen Temperaturen. Auf Blättern von Maulbeersämlingen gezogene Larven entwickelten sich schneller als auf Blättern von gepfropften Varietäten gezogene. Die Puppenperiode war jedoch bei der ersteren Nahrung länger als bei der letzteren. Die langsamere Larvenentwicklung auf den gepfropften Varietäten war mit geringerem Larven- und Puppengewicht verbunden. Unabhängig von der Temperatur und der Güte der Nahrung waren Larven und Puppen von Weibchen immer schwerer als von Männchen. Die Überlebensquote der Raupen war bei 30°C niedriger als bei 20°C oder 25°C. Sie war ferner bei gepfropftem M. alba niedriger als bei jeder anderen Nahrung. Die Seidenproduktion der Raupen war bei 25°C am höchsten und bei 30°C am geringsten. Wenn die Larven auf Blättern von Maulbeersämlingen gezogen wurden, erzeugten sie mehr Seide als bei Aufzucht auf Blättern der gepfropften Varietäten. Weibliche Raupen erzeugten stets schwerere grüne Kokons als männliche. Die Seidenhülsen der schwereren weiblichen Kokons wogen jedoch nicht mehr als die der leichteren männlichen Kokons, außer bei der ungünstigen Temperatur von 30°C bei Nahrung von Sämlingen. Die Insekten legten die größte Anzahl von Eiern, wenn sie bei 25°C gezogen wurden, und die geringste Anzahl bei 30°C. Das Gewicht der Larven und Puppen bei 20°C unterschied sich nicht von dem bei 30°C, aber die bei 30°C geringere Fruchtbarkeit als bei 20°C hängt eindeutig damit zusammen, daß das Leben der Motten bei der ersteren Temperatur kürzer ist als bei der letzteren. Auf Blättern von Maulbeersämlingen gezogene Insekten legten signifikant mehr Eier als auf Blättern von gepfropften Varietäten gezogene. Das Leben im Reifestadium war auf gepfropftem M. alba kürzer als bei jeder anderen Nahrung. Im allgemeinen lebten die Männchen länger als die Weibchen.Larvae of Bambyx mari Linnaeus were reared on food of different qualities at different temperatures. - It was found that although the rate of development was highest at 30°C and lowest at 20°C, mature larvae and pupae weighed more at 25°C. Water content of pupae reared at 20°C was higher than that at the other two temperatures. Larvae reared on leaves from seedling varieties of mulbeny developed more quickly than those reared on leaves from grafted varieties. The pupal period, however, was longer on the former than on the latter food. The lower rate of larval development on grafted varieties was associated with decreased larval and pupal weights. Irrespective of temperature and quality of food, larvae and pupae of females were always heavier than those of males. The rate of survival among caterpillars was lower at 30°C than at 20°C or 25°C. It was also lower on grafted M. alba than on any other food. Silk production by caterpillars was highest at 25°C and lowest at 30°C. When larvae were reared on leaves from seedling varieties of mulberry, they produced more silk than those reared on leaves from graf ted varieties. Female caterpillars always produced heavier green cocoons than males. Silk shells from heavier female cocoons, however, did not weigh more chan those from lighter male cocoons, except at the unfavourable temperature of 30°C on seedling foods. Insects laid the highest number of eggs when reared at 25°C and the smallest number at 30°C. There was no difference in larval and pupal weights at 20°C and 30°C, but lower fecundity at 30°C than at 20°C was definitely associated with the fact that the life of the moths was shorter at the former than at the latter temperature. Insects reared on leaves from seedling mulberry laid significantly more eggs than those reared on leaves from grafted varieties. Adult life was shorter on grafted M. alba than on any other food. Generally the males lived longer than the females

Polio survivors’ perceptions of the meaning of quality of life and strategies used to promote participation in everyday activities

This article is made available through the Brunel Open Access Publishing Fund.Introduction: The term ‘post-polio syndrome’ (PPS) is used to describe new and late manifestations of poliomyelitis that occur later in life. Research in this area has focused upon health status rather than its effect on quality of life. Aim: To gain an in-depth understanding of the meaning of quality of life for polio survivors and to determine the type of strategies that are used by people with PPS and the support that they consider as important to facilitate participation in everyday life activities that have an impact on their quality of life. Method: Six focus groups were conducted with 51 participants from two regions in England. Data were audio-taped and analysed using thematic analysis. Results: Our research found that polio survivors used terms used to describe quality of life which could be associated with that of happiness. Our research has identified resolvable factors that influence quality of life namely inaccessible environments, attitudes of health-care professionals and societal attitudes. Polio survivors have tried alternative therapies, chiefly acupuncture and massage, and found them to be effective in enhancing their quality of life. Conclusion: It is suggested that health-care professionals should consider factors which influence happiness and implement a person-centred approach with the views of the polio survivor being listened to. The three factors that influenced quality of life could be resolved by health-care professionals and by society. With regard to strategies used, we suggest that polio survivors should have access to the treatments that they perceive as important, although further research is required to design optimal interventions for this client group

Information based clustering

In an age of increasingly large data sets, investigators in many different disciplines have turned to clustering as a tool for data analysis and exploration. Existing clustering methods, however, typically depend on several nontrivial assumptions about the structure of data. Here we reformulate the clustering problem from an information theoretic perspective which avoids many of these assumptions. In particular, our formulation obviates the need for defining a cluster "prototype", does not require an a priori similarity metric, is invariant to changes in the representation of the data, and naturally captures non-linear relations. We apply this approach to different domains and find that it consistently produces clusters that are more coherent than those extracted by existing algorithms. Finally, our approach provides a way of clustering based on collective notions of similarity rather than the traditional pairwise measures.Comment: To appear in Proceedings of the National Academy of Sciences USA, 11 pages, 9 figure

Correlation effects and the high-frequency spin susceptibility of an electron liquid: Exact limits

Spin correlations in an interacting electron liquid are studied in the high-frequency limit and in both two and three dimensions. The third-moment sum rule is evaluated and used to derive exact limiting forms (at both long- and short-wavelengths) for the spin-antisymmetric local-field factor, $\lim_{\omega \to \infty}G_-({\bf q, \omega})$. In two dimensions $\lim_{\omega \to \infty}G_-({\bf q, \omega})$ is found to diverge as $1/q$ at long wavelengths, and the spin-antisymmetric exchange-correlation kernel of time-dependent spin density functional theory diverges as $1/q^2$ in both two and three dimensions. These signal a failure of the local-density approximation, one that can be redressed by alternative approaches.Comment: 5 page

Older adults’ experiences of the rehabilitation process in acute health care.

Rehabilitation is a key component of nursing and allied healthcare professionals’ roles in most health and social care settings. This paper reports on stage 2 of an action research project to ascertain older adult’s experience of rehabilitation. Twenty postdischarge interviews were conducted and the interview transcripts were analysed using thematic content analysis. All older adults discharged from an acute older acute rehabilitation ward to their own homes in the community were eligible to participate. The only exclusion criterion was older adults who were thought to be unable to give consent to participate by the nurse in charge and the researcher. Whilst 92 older adults were eligible to participate in this research study, only 20 were interviewed. The findings from this study suggest that older adults valued communication with health professionals but were aware of their time constraints that hindered communication. This study suggests that both nurses and allied health professionals are not actively providing rehabilitative services to promote health and well-being which contradicts the focus of active ageing. Furthermore, there was evidence of unmet needs on discharge, and older adults unable to recall the professions that were involved in their interventions and the rationale for therapy input. It is suggested that further research is needed to explore the effectiveness of allied health rehabilitation in the acute setting. This study highlights the need for further research into older adults’ perceptions of the rehabilitation process in the acute setting

Co-occurrence of a novel PDGFRB variant and likely pathogenic variant in CASR in an individual with extensive intracranial calcifications and hypocalcaemia

No abstract available

Food activities and identity maintenance in old age: a systematic review and meta-synthesis

This article has been made available through the Brunel Open Access Publishing Fund.Objectives: Services provided to older people should be developed based on active ageing policies. Nutrition is one aspect of active ageing, but little is known about how food activities contribute to psychological well-being in later life. This is a systematic review of qualitative and quantitative research that answers the question ‘What is known about the relationship between food activities and the maintenance of identities in old age?’

Occupational therapists’ views of using a virtual reality interior design application within the pre-discharge home visit process

This article has been made available through the Brunel Open Access Publishing Fund.Background: A key role of Occupational Therapists (OTs) is to carry out pre-discharge home visits (PHV) and propose appropriate adaptations to the home environment, to enable patients to function independently after hospital-home discharge. However, research shows that more than 50% of specialist equipment installed as part of home adaptations is not used by patients. A key reason for this is that decisions about home adaptations are often made without adequate collaboration and consultation with the patient. Consequently, there is an urgent need to seek out new and innovative uses of technology to facilitate patient/practitioner collaboration, engagement and shared decision making in the PHV process. Virtual reality interior design applications (VRIDAs) primarily allow users to simulate the home environment and visualise changes prior to implementing them. Customised VRIDAs, which also model specialist occupational therapy equipment, could become a valuable tool to facilitate improved patient/practitioner collaboration if developed effectively and integrated into the PHV process. Objective: To explore the perceptions of occupational therapists with regards to using VRIDAs as an assistive tool within the PHV process. Methods: Task-oriented interactive usability sessions, utilising the think-aloud protocol and subsequent semi-structured interviews were carried out with seven Occupational Therapists who possessed significant experience across a range of clinical settings. Template analysis was carried out on the think-aloud and interview data. Analysis was both inductive and driven by theory, centring around the parameters that impact upon the acceptance, adoption and use of this technology in practice as indicated by the Technology Acceptance Model (TAM). Results: OTs’ perceptions were identified relating to three core themes: (1) perceived usefulness (PU), (2) perceived ease of use (PEoU), and (3) actual use (AU). Regarding PU, OTs believed VRIDAs had promising potential to increase understanding, enrich communications and patient involvement, and improved patient/practitioner shared understanding. However, it was unlikely that VRIDAs would be suitable for use with cognitively impaired patients. For PEoU, all OTs were able to use the software and complete the tasks successfully, however, participants noted numerous specialist equipment items that could be added to the furniture library. AU perceptions were positive regarding use of the application across a range of clinical settings including children/young adults, long-term conditions, neurology, older adults, and social services. However, some “fine tuning” may be necessary if the application is to be optimally used in practice. Conclusions: Participants perceived the use of VRIDAs in practice would enhance levels of patient/practitioner collaboration and provide a much needed mechanism via which patients are empowered to become more equal partners in decisions made about their care. Further research is needed to explore patient perceptions of VRIDAs, to make necessary customisations accordingly, and to explore deployment of the application in a collaborative patient/practitioner-based context

Novel variants in COL4A4 and COL4A5 are rare causes of FSGS in two unrelated families

We report two female patients with focal segmental glomerulosclerosis and chronic kidney disease. The first patient was found to have a heterozygous, de novo, pathogenic variant in COL4A5 (c.141+1G>A, IVS2+1G>A), which is associated with Alport syndrome. The second patient was found to have a heterozygous, likely pathogenic variant in COL4A4 (c.2842G>T). Both these variants in COL4A5 and COL4A4 are novel, and they were detected using whole exome sequencing and gene panel testing, respectively. Additionally, we discuss the complexities of diagnosis in such cases and the benefits of using the abovementioned diagnostic approaches