22 research outputs found
Sero-survey of rubella IgM antibodies among children in Jos, Nigeria
Sero-survey of rubella IgM antibodies was carried out among children aged 0-10 years in Jos, Nigeria. Blood samples were collected from the subjects and sera extracted. Of the 93(100%) assayed for the rubella IgM antibody, 42(45.2%) were seropositive for rubella IgM antibody while 51(54.8%) were seronegative. A breakdown of the seropositive subjects reveals that 14(15.1%) of the infected children were males while 28(30.1%) were females. Those subjects within the age groups of 1-2, 3-4 and 5-6 years had the highest prevalence of 8(8.6%) followed by those within the age groups of 7-8, 9-10 years with 7(7.5%). Blood transfusion as a risk factor did not show any significant influence on the status of the subjects. The demographic data of the mothers of the subjects were also linked with the seropositivity of the children
Relative effectiveness and adverse effects of cervical manipulation, mobilisation and the activator instrument in patients with sub-acute non-specific neck pain: results from a stopped randomised trial
<p>Abstract</p> <p>Background</p> <p>Neck pain of a mechanical nature is a common complaint seen by practitioners of manual medicine, who use a multitude of methods to treat the condition. It is not known, however, if any of these methods are superior in treatment effectiveness. This trial was stopped due to poor recruitment. The purposes of this report are (1) to describe the trial protocol, (2) to report on the data obtained from subjects who completed the study, (3) to discuss the problems we encountered in conducting this study.</p> <p>Methods</p> <p>A pragmatic randomised clinical trial was undertaken. Patients who met eligibility criteria were randomised into three groups. One group was treated using specific segmental high velocity low amplitude manipulation (diversified), another by specific segmental mobilisation, and a third group by the Activator instrument. All three groups were also treated for any myofascial distortions and given appropriate exercises and advice. Participants were treated six times over a three-week period or until they reported being pain free. The primary outcome measure for the study was Patient Global Impression of Change (PGIC); secondary outcome measures included the Short-Form Health Survey (SF-36v<sub>2</sub>), the neck Bournemouth Questionnaire, and the numerical rating scale for pain intensity. Participants also kept a diary of any pain medication taken and noted any perceived adverse effects of treatment. Outcomes were measured at four points: end of treatment, and 3, 6, and 12 months thereafter.</p> <p>Results</p> <p>Between January 2007 and March 2008, 123 patients were assessed for eligibility, of these 47 were considered eligible, of which 16 were allocated to manipulation, 16 to the Activator instrument and 15 to the mobilisation group. Comparison between the groups on the PGIC adjusted for baseline covariants did not show a significant difference for any of the endpoints. Within group analyses for change from baseline to the 12-month follow up for secondary outcomes were significant for all groups on the Bournemouth Questionnaire and for pain, while the mobilisation group had a significant improvement on the PCS and MCS subscales of the SF-36<sub>v2</sub>. Finally, there were no moderate, severe, or long-lasting adverse effects reported by any participant in any group.</p> <p>Conclusions</p> <p>Although the small sample size must be taken into consideration, it appears that all three methods of treating mechanical neck pain had a long-term benefit for subacute neck pain, without moderate or serious adverse events associated with any of the treatment methods. There were difficulties in recruiting subjects to this trial. This pragmatic trial should be repeated with a larger sample size.</p
Low-tortuosity and graded lithium ion battery cathodes by ice templating
Preserving high energy densities of batteries at fast charge and discharge rates at the cell-stack level is a critical challenge for applications such as electric vehicles. Current manufacturing methods usually produce lithium (Li) ion battery electrodes <100 μm thin with unavoidable tortuous internal porosity that reduces energy densities at fast rates. Here, we use ice templating to manufacture ultra-thick (900 μm) LiFePO4-based cathodes containing fast ion transport pathways and a pore structure gradient through the electrode thickness that promote high energy densities at fast rates. The electrodes exhibit 94 mA h g−1 at an ultra-high current density of 15 mA cm−2 (67% higher gravimetric energy density at the cell-stack level including inactive components) compared with 47 mA h g−1 for conventional electrodes containing random structures and the same materials. X-ray computed tomography and modeling are used to quantify the electrode structure within different sub-domains and along orthogonal directions, which directly rationalizes the excellent dynamic performance. The electrode microstructure design, manufacturing method and characterization tools will be of use for other energy storage and conversion devices that rely on fast directional mass transport
In situ SEM Study and Microstructural Evolution of Nano Si anode for Li-ion Technology
International audienceIn situ and ex situ scanning electron microscopy of nano Si and SiO anode particles was carried out during the first cycles, and at various stages of charge. The particle size effects were explored in the range 0.1-20 μm, providing a new insight into the micro-structural evolution of the particles as a function of their size, and into the 'mechanical' resistance upon important volume change upon phase transformation of these anodes. For small particles, the failure of the battery comes from an electrochemical sintering that compacts the whole electrode, which results in its cracking. The particles keep their integrity when the discharge is stopped at a voltage 0.1V, which corresponds to the chemical composition Li12Si7, while the particles are known to crack at deeper discharge up to Li22Si5. Replacing the Si particles by SiO particles in an attempt to avoid these structural effects did not help, because of the different chemical reactions during cycling, with the loss of oxygen. Upon deeper discharge, the particles of size d<2 μm do not crack (at least during the first cycles that were investigated). On another hand, particles with 1010 μm are pulverized
A comparative study between intermittent microwave and infrared drying of bioproducts
10.1111/j.1365-2621.2004.00903.xInternational Journal of Food Science and Technology40123-3