Studies showed that assisted reproductive technology changed the sex ratio at birth, but the effect of semen processing (swim-up technique and density-gradient separation) on enriching either Xor Y-bearing sperm is always controversial. We recruited 30 healthy males and their semen samples were obtained by masturbation after sexual abstinence for 2-7 days. Each sample was divided into 3 aliquot...

This study examined how altering training intensity during a taper impacts maximal mechanical power (Pmax), torque at power maximum (T), velocity at power maximum (V), and swim performance (m . sec (-1)). Using an arm ergometer with inertial loading, measurements of Pmax, T, and V were made for 7 consecutive weeks prior to the taper and during the taper in 7 female competitive collegiate swimme...

Behavioral homology is often assumed to involve similarity in underlying neuronal mechanisms. Here, we provide a counterexample where homologous behaviors are produced by neurons with different synaptic connectivity. The nudibranch molluscs Melibe leonina and Dendronotus iris exhibit homologous swimming behaviors, consisting of alternating left and right body flexions. The swim central pattern ...

Swimming at an optimal speed is critical for breath-hold divers seeking to maximize the time they can spend foraging underwater. Theoretical studies have predicted that the optimal swim speed for an animal while transiting to and from depth is independent of buoyancy, but is dependent on drag and metabolic rate. However, this prediction has never been experimentally tested. Our study assessed t...

The pteropod mollusk Clione limacina swims by dorsal-ventral flapping movements of its wing-like parapodia. Two basic swim speeds are observed-slow and fast. Serotonin enhances swimming speed by increasing the frequency of wing movements. It does this by modulating intrinsic properties of swim interneurons comprising the swim central pattern generator (CPG). Here we examine some of the ionic cu...