482 research outputs found
Walking art as palimpsest : writing, history and the film poem.
PALIMPSEST I : Iāve used the Walking Research Group at SHU as an opportunity to address and exploit a dichotomy in my practice as a writer and cinematographer working primarily in narrative film. Iāve done this by selecting two framing devices.
Firstly, identifying The Woods as a location to walk and develop work, drawing on a number of cultural references. Secondly, using the idea of walking specifically, and film/art derived from it, as forms of Palimpsest ā one text written over another, partially erasing it. While the acts of rewriting and reworking are central to narrative film and I also wanted to compare established āstructuresā to the physical, social, psychic phenomenon of the āDesire Pathā.
PALIMPSEST II: āBABYLEGSā : Babylegs is a film/writing project that articulates the idea of palimpsest in genre and myth ā especially folk and fairytales. We rework the walks ā real and imagined ā of children through these ancient Rackhamesque woods. These elements/rushes/fragments are then reworked, with children as co-authors, in the studio with real sets and virtual environments. This reimagining draws in part on the work of Moon, Carter, together with Kitanoās āCard Narrativesā and Favat/Piaget ā The Child in the Tale ā as an interpretation of the work of the Brothers Grimm.
PALIMPSEST III - āAn Old Wood. And Deepā : Film Work in Progress
An engagement with history, and the imaginary, by walking and making in two locations, this work is also a physical realization of the palimpsest made by passing 16/35mm film through a camera twice ā once in each wood/forest. Film images will be āhalf-madeā in this wood on the outskirts of Sheffield.</p
Factors influencing the propensity to cycle to work
This paper describes the development of a mode choice model for the journey to work with special emphasis on the propensity to cycle. The model combines revealed preference (RP) and stated preference (SP) data to form a very large and comprehensive model. RP data from the National Travel Survey was combined with a specially commissioned RP survey. A number of SP surveys were also undertaken to examine the effects of different types of en-route and trip end cycle facilities and financial measures to encourage cycling.
The development of the model is described in detail. The model was used to forecast trends in urban commuting shares over time and to predict the impacts of different measures to encourage cycling. Of the en-route cycle facilities, a completely segregated cycleway was forecast to have the greatest impact, but even the unfeasible scenario of universal provision of such facilities would only result in a 55% increase in cycling and a slight reduction in car commuting. Payments for cycling to work were found to be highly effective with a Ā£2 daily payment almost doubling the level of cycling. The most effective policy would combine improvements in en-route facilities, a daily payment to cycle to work and comprehensive trip end facilities and this would also have a significant impact on car commuting
Negative tunneling magnetoresistance by canted magnetization in MgO/NiO tunnel barriers
The influence of insertion of an ultra-thin NiO layer between the MgO barrier
and ferromagnetic electrode in magnetic tunnel junctions has been investigated
by measuring the tunneling magnetoresistance and the X-ray magnetic circular
dichroism (XMCD). The magnetoresistance shows a high asymmetry with respect to
bias voltage, giving rise to a negative value of -16% at 2.8 K. We attribute
this to the formation of non-collinear spin structures in the NiO layer as
observed by XMCD. The magnetic moments of the interface Ni atoms tilt from the
easy axis due to exchange interaction and the tilting angle decreases with
increasing the NiO thickness. The experimental observations are further support
by non-collinear spin density functional theory
A genome-wide association study demonstrates significant genetic variation for fracture risk in Thoroughbred racehorses
Background:
Thoroughbred racehorses are subject to non-traumatic distal limb bone fractures that occur during racing and exercise. Susceptibility to fracture may be due to underlying disturbances in bone metabolism which have a genetic cause. Fracture risk has been shown to be heritable in several species but this study is the first genetic analysis of fracture risk in the horse.
Results:
Fracture cases (nā=ā269) were horses that sustained catastrophic distal limb fractures while racing on UK racecourses, necessitating euthanasia. Control horses (nā=ā253) were over 4 years of age, were racing during the same time period as the cases, and had no history of fracture at the time the study was carried out. The horses sampled were bred for both flat and National Hunt (NH) jump racing. 43,417 SNPs were employed to perform a genome-wide association analysis and to estimate the proportion of genetic variance attributable to the SNPs on each chromosome using restricted maximum likelihood (REML). Significant genetic variation associated with fracture risk was found on chromosomes 9, 18, 22 and 31. Three SNPs on chromosome 18 (62.05 Mb ā 62.15 Mb) and one SNP on chromosome 1 (14.17 Mb) reached genome-wide significance (pā<0.05) in a genome-wide association study (GWAS). Two of the SNPs on ECA 18 were located in a haplotype block containing the gene zinc finger protein 804A (ZNF804A). One haplotype within this block has a protective effect (controls at 1.95 times less risk of fracture than cases, pā=ā1āĆā10-4), while a second haplotype increases fracture risk (cases at 3.39 times higher risk of fracture than controls, pā=ā0.042).
Conclusions:
Fracture risk in the Thoroughbred horse is a complex condition with an underlying genetic basis. Multiple genomic regions contribute to susceptibility to fracture risk. This suggests there is the potential to develop SNP-based estimators for genetic risk of fracture in the Thoroughbred racehorse, using methods pioneered in livestock genetics such as genomic selection. This information would be useful to racehorse breeders and owners, enabling them to reduce the risk of injury in their horses
DO IT Trial: vitamin D Outcomes and Interventions in Toddlers - a TARGet Kids! randomized controlled trial.
BackgroundVitamin D levels are alarmingly low (<75 nmol/L) in 65-70% of North American children older than 1 year. An increased risk of viral upper respiratory tract infections (URTI), asthma-related hospitalizations and use of anti-inflammatory medication have all been linked with low vitamin D. No study has determined whether wintertime vitamin D supplementation can reduce the risk of URTI and asthma exacerbations, two of the most common and costly illnesses of early childhood. The objectives of this study are: 1) to compare the effect of 'high dose' (2000 IU/day) vs. 'standard dose' (400 IU/day) vitamin D supplementation in achieving reductions in laboratory confirmed URTI and asthma exacerbations during the winter in preschool-aged Canadian children; and 2) to assess the effect of 'high dose' vitamin D supplementation on vitamin D serum levels and specific viruses that cause URTI.Methods/designThis study is a pragmatic randomized controlled trial. Over 4 successive winters we will recruit 750 healthy children 1-5 years of age. Participating physicians are part of a primary healthcare research network called TARGet Kids!. Children will be randomized to the 'standard dose' or 'high dose' oral supplemental vitamin D for a minimum of 4 months (200 children per group). Parents will obtain a nasal swab from their child with each URTI, report the number of asthma exacerbations and complete symptom checklists. Unscheduled physician visits for URTIs and asthma exacerbations will be recorded. By May, a blood sample will be drawn to determine vitamin D serum levels. The primary analysis will be a comparison of URTI rate between study groups using a Poisson regression model. Secondary analyses will compare vitamin D serum levels, asthma exacerbations and the frequency of specific viral agents between groups.DiscussionIdentifying whether vitamin D supplementation of preschoolers can reduce wintertime viral URTIs and asthma exacerbations and what dose is optimal may reduce population wide morbidity and associated health care and societal costs. This information will assist in determining practice and health policy recommendations related to vitamin D supplementation in healthy Canadian preschoolers
Pharmacokinetics of Mephedrone Enantiomers in Whole Blood after a Controlled Intranasal Administration to Healthy Human Volunteers
Mephedrone, which is one of the most popular synthetic cathinones, has one chiral centre and thus exists as two enantiomers: R-(+)-mephedrone and S-(−)-mephedrone. There are some preliminary data suggesting that the enantiomers of mephedrone may display enantioselective pharmacokinetics and exhibit different neurological effects. In this study, enantiomers of mephedrone were resolved via chromatographic chiral recognition and the absolute configuration was unambiguously determined by a combination of elution order and chiroptical analysis (i.e., circular dichroism). A chiral liquid chromatography tandem mass spectrometry method was fully validated and was applied to the analysis of whole blood samples collected from a controlled intranasal administration of racemic mephedrone hydrochloride to healthy male volunteers. Both enantiomers showed similar kinetics, however, R-(+)-mephedrone had a greater mean Cmax of 48.5 ± 11.9 ng/mL and a longer mean half-life of 1.92 ± 0.27 h compared with 44.6 ± 11.8 ng/mL and 1.63 ± 0.23 h for S-(−)-mephedrone, respectively. Moreover, R-(+)-mephedrone had a lower mean clearance and roughly 1.3 times greater mean area under the curve than S-(−)-mephedrone. Significant changes in the enantiomeric ratio over time were observed, which suggest that the analytes exhibit enantioselective pharmacokinetics. Even though the clinical significance of this finding is not yet fully understood, the study confirms that the chiral nature, and consequently the enantiomeric purity of mephedrone, can be a crucial consideration when interpreting toxicological results
HIV-1 Protease, Reverse Transcriptase, and Integrase Variation
ABSTRACT HIV-1 protease (PR), reverse transcriptase (RT), and integrase (IN) variability presents a challenge to laboratories performing genotypic resistance testing. This challenge will grow with increased sequencing of samples enriched for proviral DNA such as dried blood spots and increased use of next-generation sequencing (NGS) to detect low-abundance HIV-1 variants. We analyzed PR and RT sequences from >100,000 individuals and IN sequences from >10,000 individuals to characterize variation at each amino acid position, identify mutations indicating APOBEC-mediated G-to-A editing, and identify mutations resulting from selective drug pressure. Forty-seven percent of PR, 37% of RT, and 34% of IN positions had one or more amino acid variants with a prevalence of ā„1%. Seventy percent of PR, 60% of RT, and 60% of IN positions had one or more variants with a prevalence of ā„0.1%. Overall 201 PR, 636 RT, and 346 IN variants had a prevalence of ā„0.1%. The median intersubtype prevalence ratios were 2.9-, 2.1-, and 1.9-fold for these PR, RT, and IN variants, respectively. Only 5.0% of PR, 3.7% of RT, and 2.0% of IN variants had a median intersubtype prevalence ratio of ā„10-fold. Variants at lower prevalences were more likely to differ biochemically and to be part of an electrophoretic mixture compared to high-prevalence variants. There were 209 mutations indicative of APOBEC-mediated G-to-A editing and 326 mutations nonpolymorphic treatment selected. Identification of viruses with a high number of APOBEC-associated mutations will facilitate the quality control of dried blood spot sequencing. Identifying sequences with a high proportion of rare mutations will facilitate the quality control of NGS. IMPORTANCE Most antiretroviral drugs target three HIV-1 proteins: PR, RT, and IN. These proteins are highly variable: many different amino acids can be present at the same position in viruses from different individuals. Some of the amino acid variants cause drug resistance and occur mainly in individuals receiving antiretroviral drugs. Some variants result from a human cellular defense mechanism called APOBEC-mediated hypermutation. Many variants result from naturally occurring mutation. Some variants may represent technical artifacts. We studied PR and RT sequences from >100,000 individuals and IN sequences from >10,000 individuals to quantify variation at each amino acid position in these three HIV-1 proteins. We performed analyses to determine which amino acid variants resulted from antiretroviral drug selection pressure, APOBEC-mediated editing, and naturally occurring variation. Our results provide information essential to clinical, research, and public health laboratories performing genotypic resistance testing by sequencing HIV-1 PR, RT, and IN
Health promoting universities: effective leadership for health, well-being and sustainability
Purpose
This paper reports on a research study examining opportunities for and characteristics of effective leadership for whole university approaches to health, well-being and sustainability.
Design/methodology/approach
A multi-method qualitative approach was used: semi-structured interviews and focus groups were conducted with vice chancellors (n = 12) and UK Healthy Universities Network members (n = 10) and online questionnaires were completed by non-UK network coordinators (n = 6) and non-UK health promoting university coordinators (n = 10), supplemented with two interviews.
Findings
A total of two overarching themes emerged: opportunities to secure and sustain effective senior-level leadership and characteristics of effective senior-level leadership. Sub-themes under āOpportunitiesā included aligning work with core business so that health and well-being becomes a strategic priority, harnessing the personal qualities and values of senior-level advocates and using charters and policy drivers as levers to engage and catalyse action. Sub-themes under āCharacteristicsā included commitment to whole university/whole system working; an understanding that health underpins core business and is a strategic priority; enabling effective coordination through appropriate resourcing; balancing top-down and distributed leadership models and complementing strategic leadership with cultural change.
Originality/value
This study is one of the first to explore leadership in relation to health promoting universities. Drawing on the findings, it presents a guide to developing and securing effective leadership for health promoting universities ā of value to researchers, practitioners and policymakers worldwide
Ammonium fluoride additive-modified interphase chemistry stabilizes zinc anodes in aqueous electrolytes
Herein, ammonium fluoride is reported as an additive within 1 M ZnSO4 aqueous electrolyte to improve zinc anodes. The as-formed electrostatic shielding layer and ZnF2-rich solid-state interphase layer can jointly inhibit side reactions and dendrite growth. Consequently, symmetric ZnāZn cells, asymmetric ZnāCu cells and ZnāMnO2 cells with the additives present dramatically enhanced performance in comparison to the ones with pure ZnSO4 electrolyte counterparts. This work proposes a facile but effective method to achieve highly reversible zinc anodes
Chemically treated 3D printed polymer scaffolds for biomineral formation
We present the synthesis of nylon-12
scaffolds by 3D printing and
demonstrate their versatility as matrices for cell growth, differentiation,
and biomineral formation. We demonstrate that the porous nature of
the printed parts makes them ideal for the direct incorporation of
preformed nanomaterials or material precursors, leading to nanocomposites
with very different properties and environments for cell growth. Additives
such as those derived from sources such as tetraethyl orthosilicate
applied at a low temperature promote successful cell growth, due partly
to the high surface area of the porous matrix. The incorporation of
presynthesized iron oxide nanoparticles led to a material that showed
rapid heating in response to an applied ac magnetic field, an excellent
property for use in gene expression and, with further improvement,
chemical-free sterilization. These methods also avoid changing polymer
feedstocks and contaminating or even damaging commonly used selective
laser sintering printers. The chemically treated 3D printed matrices
presented herein have great potential for use in addressing current
issues surrounding bone grafting, implants, and skeletal repair, and
a wide variety of possible incorporated material combinations could
impact many other areas
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