A direct element resequencing procedure

Element by element frontal solution algorithms are utilized in many of the existing finite element codes. The overall computational efficiency of this type of procedure is directly related to the element data input sequence. Thus, it is important to have a pre-processor which will resequence these data so as to reduce the element wavefronts to be encountered in the solution algorithm. A direct element resequencing algorithm is detailed for reducing element wavefronts. It also generates computational by products that can be utilized in pre-front calculations and in various post-processors. Sample problems are presented and compared with other algorithms

Tear film thickness variations and the role of the tear meniscus

A mathematical model is developed to investigate the two-dimensional variations in the thickness of tear fluid deposited on the eye surface during a blink. Such variations can become greatly enhanced as the tears evaporate during the interblink period.\ud The four mechanisms considered are: i) the deposition of the tear film from the upper eyelid meniscus, ii) the flow of tear fluid from under the eyelid as it is retracted and from the lacrimal gland, iii) the flow of tear fluid around the eye within the meniscus and iv) the drainage of tear fluid into the canaliculi through the inferior and superior puncta.\ud There are two main insights from the modelling. First is that the amount of fluid within the tear meniscus is much greater than previously employed in models and this significantly changes the predicted distribution of tears. Secondly the uniformity of the tear film for a single blink is: i) primarily dictated by the storage in the meniscus, ii) quite sensitive to the speed of the blink and the ratio of the viscosity to the surface tension iii) less sensitive to the precise puncta behaviour, the flow under the eyelids or the specific distribution of fluid along the meniscus at the start of the blink. The modelling briefly examines the flow into the puncta which interact strongly with the meniscus and acts to control the meniscus volume. In addition it considers flow from the lacrimal glands which appears to occurs continue even during the interblink period when the eyelids are stationary

Induction of cyclo-oxygenase-2 mRNA by prostaglandin E2 in human prostatic carcinoma cells.

Prostaglandins are synthesized from arachidonic acid by the enzyme cyclo-oxygenase. There are two isoforms of cyclooxygenases: COX-1 (a constitutive form) and COX-2 (an inducible form). COX-2 has recently been categorized as an immediate-early gene and is associated with cellular growth and differentiation. The purpose of this study was to investigate the effects of exogenous dimethylprostaglandin E2 (dmPGE2) on prostate cancer cell growth. Results of these experiments demonstrate that administration of dmPGE2 to growing PC-3 cells significantly increased cellular proliferation (as measured by the cell number), total DNA content and endogenous PGE2 concentration. DmPGE2 also increased the steady-state mRNA levels of its own inducible synthesizing enzyme, COX-2, as well as cellular growth to levels similar to those seen with fetal calf serum and phorbol ester. The same results were observed in other human cancer cell types, such as the androgen-dependent LNCaP cells, breast cancer MDA-MB-134 cells and human colorectal carcinoma DiFi cells. In PC-3 cells, the dmPGE2 regulation of the COX-2 mRNA levels was both time dependent, with maximum stimulation seen 2 h after addition, and dose dependent on dmPGE2 concentration, with maximum stimulation seen at 5 microg ml(-1). The non-steroidal anti-inflammatory drug flurbiprofen (5 microM), in the presence of exogenous dmPGE2, inhibited the up-regulation of COX-2 mRNA and PC-3 cell growth. Taken together, these data suggest that PGE2 has a specific role in the maintenance of human cancer cell growth and that the activation of COX-2 expression depends primarily upon newly synthesized PGE2, perhaps resulting from changes in local cellular PGE2 concentrations

Music listening and hearing aids: perspectives from audiologists and their patients

Objective: Two studies explored hearing-aid user and audiologist experiences of hearing-aid use and fitting for music in the UK. Design and sample: One-hundred-seventy-six hearing-aid users (age range: 21–93 years; mean: 60.56 years) answered a 4-item questionnaire on music listening difficulties and discussions about music in clinic. 99 audiologists (age range: 22–71 years; mean: 39.18 years) answered a 36-item questionnaire on the frequency and type of discussions, training received, and strategies for optimizing hearing aids for music. Closed and open-ended questions were included. Results: Sixty seven percent of hearing-aid users reported some degree of difficulty listening to music with hearing aids, and 58% had never discussed music in clinic. 50% of audiologists surveyed asked 1 in 5 (or fewer) patients about music and 67% had never received music-specific training. Audiologist training on music was significantly associated with confidence in providing advice, confidence in programming hearing aids for music, and programming hearing aids for music for a greater number of patients. Conclusions: Hearing-aid users’ and audiologists’ experiences of music remain mixed. In the absence of formalised training in optimizing hearing aids for music, there is a need for systematic research relating fitting strategies to clinical outcomes and the development of guidelines for audiologist training

The reliability of 31P-MRS and NIRS measurements of spinal muscle function

This is the accepted, peer reviewed version of the article, which has been published in final form at doi: 10.1055/s-0034-1372639Phosphorous magnetic resonance spectroscopy (31P-MRS) and near-infra red spectroscopy (NIRS) provide methods for measuring spinal muscle function non-invasively but their reliability is not established. The aim of this study was assess the reliability (ICC) and error magnitude (CV%) of measurements of muscle phosphocreatine (PCr), tissue oxygenation index (TOI), and muscle deoxyhaemoglobin (HHb) acquired during fatigue and in recovery after 24 s exercise in the lumbar muscles. Ten healthy participants (19-25 years, 5 male, 5 female) performed exercise that involved holding the upper body unsupported in slight extension until fatigue and then, after 30 minutes of rest, for repeated bursts of 24 seconds. ICCs indicated good to excellent reliability of baseline measures (TOI:0.75) and of amplitude changes during fatigue (PCr:0.73, TOI:0.69, HHb:0.80), and recovery (HHb:0.96) and poor to fair reliability for time constants describing rates of change during fatigue (PCr:0.11) and recovery (PCr:0.31, HHb:0.47). CV% indicated varying relative measurement error across baseline measures (TOI:5%), amplitude changes during fatigue (PCr:7%, TOI:38%, HHb:31%) and recovery (HHb:31%), and in time constants for fatigue (PCr:39%) and recovery (PCr:20%, HHb:37%). The results suggested that reliability would be sufficient for future studies on spinal muscle function but that measurement error may be too large to evaluate individuals.NIHREPSR

The relationship between sagittal curvature and extensor muscle volume in the lumbar spine.

This is the peer reviewed version of the article, which has been published in final form at doi: 10.1111/joa.12047. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.A previous modelling study predicted that the forces applied by the extensor muscles to stabilise the lumbar spine would be greater in spines that have a larger sagittal curvature (lordosis). Because the force-generating capacity of a muscle is related to its size, it was hypothesised that the size of the extensor muscles in a subject would be related to the size of their lumbar lordosis. Magnetic resonance imaging (MRI) data were obtained, together with age, height, body mass and back pain status, from 42 female subjects. The volume of the extensor muscles (multifidus and erector spinae) caudal to the mid-lumbar level was estimated from cross-sectional area measurements in axial T1-weighted MRIs spanning the lumbar spine. Lower lumbar curvature was determined from sagittal T1-weighted images. A stepwise linear regression model was used to determine the best predictors of muscle volume. The mean lower lumbar extensor muscle volume was 281 cm(3) (SD = 49 cm(3)). The mean lower lumbar curvature was 30 ° (SD = 7 °). Five subjects reported current back pain and were excluded from the regression analysis. Nearly half the variation in muscle volume was accounted for by the variables age (standardised coefficient, B = -3.2, P = 0.03) and lower lumbar curvature (B = 0.47, P = 0.002). The results support the hypothesis that extensor muscle volume in the lower lumbar spine is related to the magnitude of the sagittal curvature; this has implications for assessing muscle size as an indicator of muscle strength

Multiple sclerosis or neuromyelitis optica? Re-evaluating an 18th-century illness using 21st-century software

In this paper we report the application of an extensive database of symptoms, signs, laboratory findings and illnesses, to the diagnosis of an historical figure. The medical diagnosis of Augustus d'Este (1794–1848) – widely held to be the first documented case of multiple sclerosis – is reviewed, using the detailed symptom diary, which he kept over many years, as clinical data. Some of the reported features prompted the competing claim that d'Este suffered from acute porphyria, which in turn was used in support of the hypothesis that his grandfather, King George III, also suffered from the disease. We find that multiple sclerosis is statistically the most likely diagnosis, with neuromyelitis optica a strong alternative possibility. The database did not support a diagnosis of any of the acute porphyrias

Inherent and learnt abilities for relative pitch in the vibrotactile domain using the fingertip

This paper reports experimental results concerning relative pitch discrimination. This is defined as the ability to distinguish one musical note as being higher or lower than another. Seventeen participants with normal hearing undertook a pitch discrimination experiment using the fingertip over a 16 session training period with a full baseline test before and after the training sessions. Two sinusoidal tones were presented, each of Is duration separated by a Is gap. A total of 24 tones were chosen to cover 12 intervals ranging from a semi-tone to an octave over the frequency range C3 to B4. The results show a high success rate for relative pitch discrimination with and without training. For intervals of 4 to 12 semitones, the success rates were >70% with or without the 16 training sessions. As a result of training, a significant improvement was found for individual intervals between 9 and 12 semitones when comparing the number of correct responses between pre-training and post-training tests. Comparison of pre- and post-training tests also showed an appreciable and significant improvement for the whole group of 12 intervals. In addition, reaction times to identify relative pitch tended to decrease over the training period

Differential pathways to adult metabolic dysfunction following poor nutrition at two critical developmental periods in sheep

Epidemiological and experimental studies suggest early nutrition has long-term effects on susceptibility to obesity, cardiovascular and metabolic diseases. Small and large animal models confirm the influence of different windows of sensitivity, from fetal to early postnatal life, on offspring phenotype. We showed previously that undernutrition in sheep either during the first month of gestation or immediately after weaning induces differential, sex-specific changes in adult metabolic and cardiovascular systems. The current study aims to determine metabolic and molecular changes that underlie differences in lipid and glucose metabolism induced by undernutrition during specific developmental periods in male and female sheep. Ewes received 100% (C) or 50% nutritional requirements (U) from 1–31 days gestation, and 100% thereafter. From weaning (12 weeks) to 25 weeks, offspring were then fed either ad libitum (CC, UC) or were undernourished (CU, UU) to reduce body weight to 85% of their individual target. From 25 weeks, all offspring were fed ad libitum. A cohort of late gestation fetuses were studied after receiving either 40% nutritional requirements (1–31 days gestation) or 50% nutritional requirements (104–127 days gestation). Post-weaning undernutrition increased in vivo insulin sensitivity, insulin receptor and glucose transporter 4 expression in muscle, and lowered hepatic methylation at the delta-like homolog 1/maternally expressed gene 3 imprinted cluster in adult females, but not males. Early gestational undernutrition induced lower hepatic expression of gluconeogenic factors in fetuses and reduced in vivo adipose tissue insulin sensitivity in adulthood. In males, undernutrition in early gestation increased adipose tissue lipid handling mechanisms (lipoprotein lipase, glucocorticoid receptor expression) and hepatic methylation within the imprinted control region of insulin-like growth factor 2 receptor in adulthood. Therefore, undernutrition during development induces changes in mechanisms of lipid and glucose metabolism which differ between tissues and sexes dependent on the period of nutritional restriction. Such changes may increase later life obesity and dyslipidaemia risk