4,111 research outputs found
Dynamic response of a thin sessile drop of conductive liquid to an abruptly applied or removed electric field
We consider, both theoretically and experimentally, a thin sessile drop of conductive liquid that rests on the lower plate of a parallel-plate capacitor. We derive analytical expressions for both the initial deformation and the relaxation dynamics of the drop as the electric field is either abruptly applied or abruptly removed, as functions of the geometrical, electrical, and material parameters, and investigate the ranges of validity of these expressions by comparison with full numerical simulations. These expressions provide a reasonable description of the experimentally measured dynamic response of a drop of conductive ionic liquid 1-butyl-3-methyl imidazolium tetrafluoroborate
A Review of Dietary Zinc Recommendations
Background. Large discrepancies exist among the dietary zinc recommendations set by expert groups.
Objective. To understand the basis for the differences in the dietary zinc recommendations set by the World Health Organization, the U.S. Institute of Medicine, the International Zinc Nutrition Consultative Group, and the European Food Safety Agency.
Methods. We compared the sources of the data, the concepts, and methods used by the four expert groups to set the physiological requirements for absorbed zinc, the dietary zinc requirements (termed estimated and/or average requirements), recommended dietary allowances (or recommended nutrient intakes or population reference intakes), and tolerable upper intake levels for selected age, sex, and life-stage groups.
Results. All four expert groups used the factorial approach to estimate the physiological requirements for zinc. These are based on the estimates of absorbed zinc required to offset all obligatory zinc losses plus any additional requirements for absorbed zinc for growth, pregnancy, or lactation. However, discrepancies exist in the reference body weights used, studies selected, approaches to estimate endogenous zinc losses, the adjustments applied to derive dietary zinc requirements that take into account zinc bioavailability in the habitual diets, number of dietary zinc recommendations set, and the nomenclature used to describe them.
Conclusions. Estimates for the physiological and dietary requirements varied across the four expert groups. The European Food Safety Agency was the only expert group that set dietary zinc recommendations at four different levels of dietary phytate for adults (but not for children) and as yet no tolerable upper intake level for any life-stage group
Electric field induced deformation of hemispherical sessile droplets of ionic liquid
Sessile droplets of an ionic liquid with contact angles close to 90° were subjected to an electric field E = V/w inside a capacitor with plate separation w and potential difference V. For small field induced deformations of the droplet shape the change in maximum droplet height, Δh = h(E) – h(0), was found to be virtually independent of the plate separation provided that w > 3h(0). In this regime a scaling law obtains Δh α E2r2, where r is the constant droplet radius, in agreement with the asymptotic predictions of Basaran and Scriven (J. Coll. Int. Sci. 140, 10, 1990)
Abnormal expression of p27kip1 protein in levator ani muscle of aging women with pelvic floor disorders – a relationship to the cellular differentiation and degeneration
BACKGROUND: Pelvic floor disorders affect almost 50% of aging women. An important role in the pelvic floor support belongs to the levator ani muscle. The p27/kip1 (p27) protein, multifunctional cyclin-dependent kinase inhibitor, shows changing expression in differentiating skeletal muscle cells during development, and relatively high levels of p27 RNA were detected in the normal human skeletal muscles. METHODS: Biopsy samples of levator ani muscle were obtained from 22 symptomatic patients with stress urinary incontinence, pelvic organ prolapse, and overlaps (age range 38–74), and nine asymptomatic women (age 31–49). Cryostat sections were investigated for p27 protein expression and type I (slow twitch) and type II (fast twitch) fibers. RESULTS: All fibers exhibited strong plasma membrane (and nuclear) p27 protein expression. cytoplasmic p27 expression was virtually absent in asymptomatic women. In perimenopausal symptomatic patients (ages 38–55), muscle fibers showed hypertrophy and moderate cytoplasmic p27 staining accompanied by diminution of type II fibers. Older symptomatic patients (ages 57–74) showed cytoplasmic p27 overexpression accompanied by shrinking, cytoplasmic vacuolization and fragmentation of muscle cells. The plasma membrane and cytoplasmic p27 expression was not unique to the muscle cells. Under certain circumstances, it was also detected in other cell types (epithelium of ectocervix and luteal cells). CONCLUSIONS: This is the first report on the unusual (plasma membrane and cytoplasmic) expression of p27 protein in normal and abnormal human striated muscle cells in vivo. Our data indicate that pelvic floor disorders are in perimenopausal patients associated with an appearance of moderate cytoplasmic p27 expression, accompanying hypertrophy and transition of type II into type I fibers. The patients in advanced postmenopause show shrinking and fragmentation of muscle fibers associated with strong cytoplasmic p27 expression
Border Terriers under primary veterinary care in England: demography and disorders
The Border Terrier is a working terrier type that is generally considered to be a relatively healthy and hardy breed. This study aimed to characterise the demography and common disorders of Border Terriers receiving veterinary care in England using de-identified electronic patient record data within the VetCompassâ„¢ Programme
International students and further education colleges in England: The context, policy tensions, and some aspects of practice
This chapter sets out the context of publicly funded further education colleges in England, outlining the position and development of these complex institutions within the broader educational structure. This is followed by discussion of some tensions and contradictions which arise from government policies partially driven by anxieties derived from debates surrounding levels of immigration together with recognition of the imperatives and opportunities arising from globalisation. The benefits of the internationalisation of education have been expounded whilst simultaneously enforcing visa regulations which impede the efforts of colleges to make inroads in the international student market. In particular, disparities between the treatment of the further and higher education sectors are highlighted. The paper also provides an account of practices which have emerged in a single FE college in England over a decade of working with international students following an access to HE course. The chapter indicates some of the many benefits which have been brought to FE by international students as well as the ways in which a college has developed its practices in response to their needs
Oral health problems and risk of incident disability in two studies of older adults in the United Kingdom and the United States.
BACKGROUND: Preventing oral health problems can be crucial for maintaining physical independence in older adults. We aimed to examine the associations of a range of oral health problems with incidence of disability in older adults. METHODS: We used prospective data from the British Regional Health Study (BRHS) (N = 2147, 71-92 years), and the Health, Aging and Body Composition (HABC) study (USA) (N = 3075, 71-80 years). Oral health measures included tooth loss, periodontal disease, self-rated oral health, and self-reported dry mouth. Participants were followed for onset of disability over a follow-up period of 3 years. Onset of disability was assessed through new cases of mobility limitations, activities of daily living (ADL), and instrumental activities of daily living (IADL). Logistic regression was performed to calculate the odds of incident disability. RESULTS: In the BRHS, tooth loss was associated with greater odds of mobility limitations and ADL difficulties. Periodontal disease was associated with greater incidence of mobility limitations. Self-report of ≥3 dry mouth symptoms was associated with increased odds of incident mobility limitations and ADL difficulties (OR = 2.08, 95% CI 1.27-3.42; OR = 1.73, 95% CI 1.03-2.90). Fair/poor self-rated oral health was associated with greater incidence of IADL difficulties. In the HABC study, complete tooth loss was associated with greater incidence of mobility limitations (OR = 1.86, 95% CI 1.13-3.06), and fair/poor self-rated oral health was associated with increased odds of incident ADL difficulties (OR = 1.42, 95% CI 1.04-1.94). CONCLUSIONS: Oral health problems in older adults, particularly tooth loss, self-reported dry mouth and self-rated oral health were associated with greater incidence of disability. Poor oral health plays a potentially important role in the development of disability in older populations, which in turn is an essential part of quality of life and healthy aging
Poor oral health and the association with diet quality and intake in older people in two studies in the UK and USA.
We aimed to investigate the associations of poor oral health cross-sectionally with diet quality and intake in older people. We also examined whether change in diet quality is associated with oral health problems. Data from the British Regional Heart Study (BRHS) comprising British males aged 71-92 years and the Health, Aging and Body Composition (HABC) Study comprising American males and females aged 71-80 years were used. Dental data included tooth loss, periodontal disease, dry mouth and self-rated oral health. Dietary data included diet quality (based on Elderly Dietary Index (BRHS) and Healthy Eating Score (HABC Study)) and several nutrients. In the BRHS, change in diet quality over 10 years (1998-2000 to 2010-2012) was also assessed. In the BRHS, tooth loss, fair/poor self-rated oral health and accumulation of oral health problems were associated with poor diet quality, after adjustment. Similar associations were reported for high intake of processed meat. Poor oral health was associated with the top quartile of percentage of energy content from saturated fat (self-rated oral health, OR 1·34, 95 % CI 1·02, 1·77). In the HABC Study, no significant associations were observed for diet quality after adjustment. Periodontal disease was associated with the top quartile of percentage of energy content from saturated fat (OR 1·48, 95 % CI 1·09, 2·01). In the BRHS, persistent low diet quality was associated with higher risk of tooth loss and accumulation of oral health problems. Older individuals with oral health problems had poorer diets and consumed fewer nutrient-rich foods. Persistent poor diet quality was associated with oral health problems later in life
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