Supplemental Learning in the Laboratory: An Innovative Approach for Evaluating Knowledge and Method Transfer.

The Multi-Rule Quality Control System (MRQCS) is a tool currently employed by the Centers for Disease Control and Prevention (CDC) to evaluate and compare laboratory performance. We have applied the MRQCS to a comparison of instructor and computer-led pre-laboratory lectures for a supplemental learning experiment. Students in general chemistry and analytical chemistry from both two- and four-year institutions performed two laboratory experiments as part of their normal laboratory curriculum. The first laboratory experiment was a foundational learning experiment in which all the students were introduced to Beer-Lambert's Law and spectrophotometric light absorbance measurements. The foundational learning experiment was instructor-led only, and participant performance was evaluated against a mean characterized value. The second laboratory experiment was a supplemental learning experiment in which students were asked to build upon the methodology they learned in the foundational learning experiment and apply it to a different analyte. The instruction type was varied randomly into two delivery modes, participants receiving either instructor-led or computer-led pre-laboratory instruction. The MRQCS was applied and determined that no statistical difference was found to exist in the QC (quality control) passing rates between the participants in the instructor-led instruction and the participants in the computer-led instruction. These findings demonstrate the successful application of the MRQCS to evaluate knowledge and technology transfer.

A multi-domain fragment of Nogo-A protein is a potent inhibitor of cortical axon regeneration via Nogo receptor 1.

Nogo-A limits axon regeneration and functional recovery after central nervous system injury in adult mammals. Three regions of Nogo-A (Nogo-A-24, Nogo-66, and Nogo-C39) interact with the neuronal Nogo-66 receptor 1 (NgR1). Nogo-66 also interacts with a structurally unrelated cell surface receptor, paired immunoglobulin-like receptor (PirB). We show here that the other two NgR1-interacting domains, Nogo-A-24 and Nogo-C39, also bind to PirB with high affinity. A purified 22-kDa protein containing all three NgR1- and PirB-interacting domains (Nogo-22) is a substantially more potent growth cone-collapsing molecule than Nogo-66 for chick dorsal root ganglion neurons and mature cortical neurons. Moreover, Nogo-22 inhibits axon regeneration of mature cortical neurons in vitro more potently than does Nogo-66. Although all three NgR1-interacting domains of Nogo-A also interact with PirB, expression of PirB in mature cortical cultures is nearly undetectable. Consistent with a relatively minor role for PirB in mature cortical neurons, Nogo-22 inhibition of axon regeneration is abolished by genetic deletion of NgR1. Thus, NgR1 is the predominant receptor for Nogo-22 in regenerating cortical neurons.

Establishing 24-hour Holter reference intervals for clinically healthy puppies.

Normal Holter reference intervals have not been established for dogs <1 year of age. This lack of Holter reference intervals inhibits the ability to screen puppies for early indicators of heart disease, especially in breeds that have inherited cardiac arrhythmias (e.g. German Shepherd Dogs) or a high incidence of arrhythmic heart disease (e.g. Boxer dogs). The objective of this project was to establish Holter minimum, average, and maximum heart rates and incidence of arrhythmias in clinically healthy dogs <1 year of age and to compare these results to previously reported Holter data for their adult counterparts. Forty-four client-owned clinically healthy puppies between 12 and 51 weeks of age were prospectively studied. Age was determined by date of birth and corroborated by dental examination. Puppies were deemed healthy based on history and physical examination. Puppies with heart murmurs underwent echocardiographic examination. Dogs with physiologic heart murmurs were included. Twenty-four hour ECG recordings were obtained using a digital Holter system. The median (interquartile range) Holter minimum, average, and maximum heart rates were 51 bpm (43-60 bpm), 99 bpm (85-113 bpm), and 274 bpm (257-291 bpm), respectively. The median for ventricular and supraventricular arrhythmias was 0. Ventricular and supraventricular premature complexes were identified in 4/44 (9%) and 6/44 (13%) puppies, respectively. Second degree atrioventricular block was identified in 2/44 puppies (5%). Overall, minimum, average, and maximum Holter heart rates of puppies are higher than adult dogs. The incidence of ventricular and supraventricular premature complexes in puppies is similar to adult dogs.

Patterned functional carbon fibers from polyethylene.

Carbon fibers having unique morphologies, from hollow circular to gear-shaped, are produced from a novel melt-processable precursor and method. The resulting carbon fiber exhibits microstructural and topological properties that are dependent on processing conditions, rendering them highly amenable to myriad applications.