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The catalytic oxidation of biomass to new materials focusing on starch, cellulose and lignin
Biomass is a renewable class of materials of growing interest amongst researchers aiming to achieve global sustainability. This review focuses on the homogeneous catalysis of the oxidation of biomass, in particular starch, cellulose and lignin. Often such catalytic reactions lead to depolymerisation of the material as happens in Nature with for example brown rot fungi. This depolymerisation can be desirable or not, and control in industrial applications is thus important to obtain the desired outcome. The two main oxidants in use are O2 and H2O2 and their use is described as appropriate. Industrial oxidation catalysis is highly significant in the bleaching of cellulose-containing materials due to its high volume application in the paper, pulp and laundry industries. Here, the presence of a ligand on the oxidising metal ion has a significant effect on the catalyst selectivity and stability. In addition to the bleaching of cellulose-containing materials, the oxidation of cellulose, starch, lignin and lignin model compounds are discussed with a focus on generating even more hydrophilic materials which have important applications or materials which may be further modified. Finally developing applications of biomass are described such as new support materials for catalysts, as supports for sensors and nanomaterials for microbial culture
The clubhead and hand planes in golf draw and fade shots.
Swing planes in golf have become a popular area of research. Cochran and Stobbs (1968) examined the motion of the clubhead and hands qualitatively. Subsequent quantitative analyses have included investigations of the planarity of the whole club (Coleman & Anderson, 2007) and clubhead (Shin, Casebolt, Lambert, Kim, & Kwon, 2008). The aim of this study was to investigate the motion of the
clubhead and hands in the downswing quantitatively, and to compare these motions for the fade and draw (as suggested by Coleman and Anderson, 2007).
In conclusion, both the clubhead and hand planes in the late downswing were found to differ significantly in relation to the target line between the draw and fade shots. Greater differences were found between golfers, rather than between shots, in the relationship between the clubhead and hand motion during the downswing. Nevertheless, further detailed analysis is warranted of how the motions around impact â especially the clubface orientation â differ between the two types of shot
The clubhead swing plane in golf draw and fade shots
It has become popular to characterise a golf shot in terms of a âswing planeâ. However Coleman and Anderson (2007) showed that the motion of the whole club in the downswing could not be represented by a single plane in all players. Shin et al. (2008) found that the clubhead motion was consistently planar between the club being horizontal in the downswing and follow-through. Coleman and Anderson (2007) also suggested that the club plane might differ between draw and fade shots. The purpose of this study was to compare draw and fade shots, with a focus on the clubhead motion in the late downswing.
The late downswing clubhead plane differs between a draw and a fade shot, even when differences in address angles are accounted for
ADM Worldvolume Geometry
We describe the dynamics of a relativistic extended object in terms of the
geometry of a configuration of constant time. This involves an adaptation of
the ADM formulation of canonical general relativity. We apply the formalism to
the hamiltonian formulation of a Dirac-Nambu-Goto relativistic extended object
in an arbitrary background spacetime.Comment: 4 pages, Latex. Uses espcrc2.sty To appear in the proceedings of the
Third Conference on Constrained Dynamics and Quantum Gravity, September,
1999. To appear in Nuclear Physics B (Proceedings Supplement
Prolonging disuse in aged mice amplifies cortical but not trabecular bonesâ response to mechanical loading
Objective: Short-term neurectomy-induced disuse (SN) has been shown to restore load responses in aged mice. We examined whether this restoration was further enhanced in both cortical and trabecular bone by simply extending the SN. Methods: Following load: strain calibration, tibiae in female C57BL/J6 mice at 8, 14 and 20 weeks and 18 months (n=8/group) were loaded and bone changes measured. Effects of long-term SN examined in twenty-six 18 months-old mice, neurectomised for 5 or 100 days with/without subsequent loading. Cortical and trabecular responses were measured histomorphometrically or by micro-computed tomography. Results: Loading increased new cortical bone formation, elevating cross-sectional area in 8, 14 and 20 week-old (p <0.05), but not 18 month-old aged mice. Histomorphometry showed that short-term SN reinstated load-responses in aged mice, with significant 33% and 117% increases in bone accrual at 47% and 37%, but not 27% of tibia length. Cortical responses to loading was heightened and widespread, now evident at all locations, following prolonged SN (108, 167 and 98% at 47, 37 and 27% of tibial length, respectively). In contrast, loading failed to modify trabecular bone mass or architecture. Conclusions: Mechanoadaptation become deficient with ageing and prolonging disuse amplifies this response in cortical but not trabecular bone
âWe may be falling apart but we still keep goingâ: Retired servicemenâs experiences of their ageing bodies
Currently, there is scant research that investigates in-depth retired servicemenâs perceptions and experiences of ageing and being physically active, particularly in relation to retirement experiences. In this article, we employ a novel theoretical combination of figurational sociology
and symbolic interactionism to explore a topical life history of 20 retired servicemenâs experiences in relation to physical activity (PA), the ageing body and constructions of identity in later life. Participants were aged 60+
and members of the Royal British Legion in a city in the English Midlands. Three semi-structured focus-group interviews and follow-up conversations were completed, together with informal observations. Key findings revealed that although participants recognised the need for regular PA, their perceptions routinely centred upon the âfeltâ limitations of the ageing body, often in stark contrast to their former âdisciplinedâ, active, military
bodies. Corporeal challenges and limitations discouraged some from taking part in PA altogether. Despite their perceived bodily limitations, however, many ex-service personnel still endeavoured to stay physically active.
Findings highlight the salience of the temporal aspects of older adultsâ lived experiences of exercise and PA, for past experiences of PA and exercise were identified as strongly shaping current-day motivations, attitudes and behaviours
A stable variational autoencoder for text modelling
Variational Autoencoder (VAE) is a powerful method for learning representations of high-dimensional data. However, VAEs can suffer from an issue known as latent variable collapse (or KL term vanishing), where the posterior collapses to the prior and the model will ignore the latent codes in generative tasks. Such an issue is particularly prevalent when employing VAE-RNN architectures for text modelling (Bowman et al., 2016; Yang et al., 2017). In this paper, we present a new architecture called Full-Sampling-VAE-RNN, which can effectively avoid latent variable collapse. Compared to the general VAE-RNN architectures, we show that our model can achieve much more stable training process and can generate text with significantly better quality
The occupational role of the lay health trainer in England: a review of practice
Health Trainers constitute an emergent occupational group in the Public Health system in England with the key purpose to reduce health inequalities by helping or ânudgingâ people in local communities to adopt healthier lifestyles. Whilst primarily supplying health-related information and support regarding smoking cessation, diet, alcohol, physical activity and mental wellbeing issues, the role also requires awareness of, and sensitivity toward the specific needs of local communities. This literature review charts current research on the occupational context of the Health Trainer role since its implementation in the English Public Health system. It provides a critical examination of current literature whilst highlighting the theoretical basis of Health Trainersâ roles, the potential boundary-crossing nature of their work, along with professional development issues
Protein translocation:whatâs the problem?
We came together in Leeds to commemorate and celebrate the life and achievements of Prof. Stephen Baldwin. For many years we, together with Sheena Radford and Roman Tuma (colleagues also of the University of Leeds), have worked together on the problem of protein translocation through the essential and ubiquitous Sec system. Inspired and helped by Steve we may finally be making progress. My seminar described our latest hypothesis for the molecular mechanism of protein translocation, supported by results collected in Bristol and Leeds on the tractable bacterial secretion processâcommonly known as the Sec system; work that will be published elsewhere. Below is a description of the alternative and contested models for protein translocation that we all have been contemplating for many years. This review will consider their pros and cons
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