INTRODUCTION Nigeria, the only African country endemic for wild poliovirus, adopted Immunization Plus Days (IPD) to eradicate polio. Refusal of oral polio vaccine (OPV) by heads of households is a significant challenge. In Sokoto state, we determined characteristics of heads of households refusing OPV during IPD in 2011. METHODS To evaluate reasons for refusals, we conducted a case control st...

We propose a technique to compute the fraction of boar spermatozoid heads which present an intracellular density distribution pattern hypothesized as normal by veterinary experts. This approach offers a potential for digital image processing estimation of sperm capacitation which can substitute expensive staining techniques. We extract a model distribution from a training set of heads assumed a...

Cycl AMP concentrations were elevated and acrosome reactions were induced in intact sea urchin spermatozoa by Nigericin, A23187, and pH 9.0 seawater. To determine whether or not the metabolism of cyclic AMP was being altered in sperm heads, the heads were mechanically separated from the flagella, and the flagella-less heads were then isolated by differential centrifugation. The isolated heads c...

Due to the complex geometry and thermos-mechanical loading, cylinder heads are the most challenging parts among all parts engines. They must endure cyclic thermal and mechanical loading throughout their lifetime. Cast aluminum alloys are normally quenched after solution treatment process to improve aging responses. Rapid quenching can lead to high residual stress. Residual stress is one of the ...

Schwann cells don caps, touch nodes n vertebrates, axons are covered with an insulating myelin sheath, punctuated by gaps called nodes of Ranvier where voltage-gated sodium channels cluster. The nodes are essential for propagating action potentials along the axon, but little is known about how they develop. Gatto et al. (page 489) imaged live cell cultures to watch Schwann cells myelinate expla...