Distinct neural mechanisms mediate olfactory memory formation at different timescales.

Habituation is one of the oldest forms of learning, broadly expressed across sensory systems and taxa. Here, we demonstrate that olfactory habituation induced at different timescales (comprising different odor exposure and intertrial interval durations) is mediated by different neural mechanisms. First, the persistence of habituation memory is greater when mice are habituated on longer timescales.

Comparative anatomy of the electrosensory lateral line lobe of mormyrids: the mystery of the missing map in the genus Stomatorhinus (family: Mormyridae).

Fish in the family Mormyridae produce weak electric organ discharges that are used in orientation and communication. The peripheral and central anatomy of the electrosensory system has been well studied in the species Gnathonemus petersii, but comparative studies in other species are scarce. Here we report on one genus of mormyrid that displays a remarkable change in the electrosensory lateral line lobe (ELL), the hypertrophied rhombencephalic structure that receives primary electroreceptor input.

Prognostic factors in mortality and morbidity in patients with differentiated thyroid cancer.

We attempted to determine if women younger than 45 years of age who have isolated papillary thyroid cancer and whose tumors are smaller than 4 cm (T2N0M0) are at low risk for mortality and morbidity following thyroid lobectomy. To this end, we analyzed information on both women and men obtained from our review of the literature, and we integrated it with data compiled in the Delaware Cancer Registry. We performed a secondary analysis to determine if the risk of death and recurrence can be predicted on the basis of age, tumor size, sex, histology, and the type of operation.

Incidence of Escherichia coli O157:H7 in frozen beef patties produced over an 8-hour shiftt.

A ground beef patty processor detected Escherichia coli O157:H7 in five production lots during routine testing with polymerase chain reaction (PCR) technology. This finding stimulated research to determine the incidence and potential entry points of the pathogen during processing. One of these lots (53,960 kg) was divided into 71 pallets (760 kg each) of food service ground beef patties.