University of Bath

About: University of Bath is a education organization based out in Bath, Bath and North East Somerset, United Kingdom. It is known for research contribution in the topics: Population & Photonic-crystal fiber. The organization has 15830 authors who have published 39608 publications receiving 1358769 citations. The organization is also known as: Bath University.

Analysis of Battery Lifetime Extension in a Small-Scale Wind-Energy System Using Supercapacitors

Abstract: Due to the variable characteristics of renewable generation, batteries used in renewable-power systems can undergo many irregular, partial charge/discharge cycles. In turn, this can also have a detrimental effect on battery lifetime and can increase project costs. This study presents a method of improving battery lifetime in a small-scale remote-area wind-power system by the use of a battery/supercapacitor hybrid energy storage system. The supervisory control algorithm and hardware implementation are described and projected long-term benefits of the proposed system are assessed by simulation. A representative dynamic model of the overall system, incorporating realistic wind-speed and load-power variations has been developed. An analysis is presented of the potential improvement in battery lifetime that is achievable by diverting short-term charge/discharge cycles to a supercapacitor energy-storage system. This study introduces a method by which supercapacitor energy storage systems and control algorithms can be evaluated and implemented in the application area considered. The composition of a prototype test system is described and experimental results are presented to demonstrate system feasibility.

Precise Localization of α7 Nicotinic Acetylcholine Receptors on Glutamatergic Axon Terminals in the Rat Ventral Tegmental Area

Abstract: α7 neuronal nicotinic acetylcholine receptors (nAChRs) constitute one of the predominant nAChR subtypes in the mammalian brain. Within the ventral tegmental area (VTA), nicotine application, paired with postsynaptic stimulation, contributes to a form of long-term potentiation, an effect attributed to presynaptic α7 nAChRs on glutamatergic afferents ([Mansvelder and McGehee, 2000][1]). The aim of this study was to examine the precise subcellular distribution of α7 nAChRs in the adult rat VTA to establish whether these receptors are indeed present on glutamatergic axon terminals and to determine their relationship with cholinergic afferents. The spatial relationship between α7 nAChRs, labeled using the α7 nAChR-specific antagonist α-bungarotoxin, and the local neurochemical environment was investigated by the application of multiple labeling strategies with antibodies against tyrosine hydroxylase, vesicular glutamate transporters (VGluTs), vesicular acetylcholine transporter, and glial fibrillary acidic protein. α7 nAChRs were localized at both somatodendritic and presynaptic loci within the VTA: on subpopulations of dopaminergic and nondopaminergic neurons and glutamatergic and nonglutamatergic terminals. There was no detectable α7 nAChR expression within astrocytes in the VTA. Most α7 nAChRs were cytoplasmic (82%), and the remainder were associated with the plasma membrane. Most presynaptic receptors (75%) were on glutamatergic axon terminals, with similar levels of α-bungarotoxin binding present on both VGluT1- and VGluT2-immunoreactive boutons. Both preembedding and postembedding electron microscopy revealed that presynaptic α7 nAChRs are often located at extrasynaptic (27%) and perisynaptic (61%) loci. α7 nAChRs were not associated with cholinergic synapses, consistent with their activation by a paracrine mode of acetylcholine or choline delivery. [1]: #ref-28

Exploring SME Internet Adoption: Towards a Contingent Model

Abstract: Internet adoption, in both large and small firms (SMEs), is promoted as a means to improve competitiveness. The European Union and various national governments encourage Internet adoption predicated upon an 'adoption ladder' or stages model. This model only requires that the business starts on the bottom rung of the ladder for upward progression to then begin. There is, however, little research that supports such a stages model. Therefore, this paper questions current thinking that small firms progress through a 'stages of growth' model in their use of the Internet. Twelve SME cases are investigated. Outcomes suggest that the majority only perceive value in email and possibly a marketing website. However, some SMEs see strategic potential and will invest in e-business. The paper suggests that owners' recognition of the business value of the Internet combined with their attitude to business growth are key factors in determining Internet adoption strategies. Thus, SMEs will aim for specific adoption strateg...

Correlates of Total Sedentary Time and Screen Time in 9-11 Year-Old Children around the World: The International Study of Childhood Obesity, Lifestyle and the Environment.

Abstract: Purpose Previously, studies examining correlates of sedentary behavior have been limited by small sample size, restricted geographic area, and little socio-cultural variability. Further, few studies have examined correlates of total sedentary time (SED) and screen time (ST) in the same population. This study aimed to investigate correlates of SED and ST in children around the world. Methods The sample included 5,844 children (45.6% boys, mean age = 10.4 years) from study sites in Australia, Brazil, Canada, China, Colombia, Finland, India, Kenya, Portugal, South Africa, the United Kingdom, and the United States. Child- and parent-reported behavioral, household, and neighborhood characteristics and directly measured anthropometric and accelerometer data were obtained. Twenty-one potential correlates of SED and ST were examined using multilevel models, adjusting for sex, age, and highest parental education, with school and study site as random effects. Variables that were moderately associated with SED and/or ST in univariate analyses (p<0.10) were included in the final models. Variables that remained significant in the final models (p<0.05) were considered correlates of SED and/or ST. Results Children averaged 8.6 hours of daily SED, and 54.2% of children failed to meet ST guidelines. In all study sites, boys reported higher ST, were less likely to meet ST guidelines, and had higher BMI z-scores than girls. In 9 of 12 sites, girls engaged in significantly more SED than boys. Common correlates of higher SED and ST included poor weight status, not meeting physical activity guidelines, and having a TV or a computer in the bedroom. Conclusions In this global sample many common correlates of SED and ST were identified, some of which are easily modifiable (e.g., removing TV from the bedroom), and others that may require more intense behavioral interventions (e.g., increasing physical activity). Future work should incorporate these findings into the development of culturally meaningful public health messages.