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Cullin-3 Targets Cyclin E For Ubiquitination And Controls S Phase In Mammalian Cells, Jeffrey D. Singer, Mark Gurian-West, Bruce Clurman, James M. Roberts

Biology Faculty Publications and Presentations

Cyclin E is an unstable protein that is degraded in a ubiquitin- and proteasome- dependent pathway. Two factors stimulate cyclin E ubiquitination in vivo: when it is free of its CDK partner, and when it is phosphorylated on threonine 380. We pursued the first of these pathways by using a two-hybrid screen to identify proteins that could bind only to free cyclin E. This resulted in the isolation of human Cul-3, a member of the cullin family of E3 ubiquitin–protein ligases. We found that Cul-3 was bound to cyclin E but not to cyclin E-Cdk2 complexes in mammalian cells, and …

Acorn Foraging As A Means To Explore Human Energetics And Forge Connections To Local Forests, Jeffrey J. Gerwing, Pamela Lockwood, Christopher Uhl

Environmental Science and Management Faculty Publications and Presentations

Jeffrey Gerwing, Pamela Lockwood, and Christopher Uhl describe a rather unusual ecology laboratory/field exercise that utilizes abundant oak habitats of central Pennsylvania. For those readers not blessed with an abundant supply of oaks nearby, perhaps other species could be substituted. The exercise is unusual in two ways. It offers a new undergraduate ecology activity, and it offers opportunities for students to relate other disciplines to their science course.

In "the good old days" of higher education each discipline offered its menu of courses and expected students to make appropriate connections among the courses of their major, minor, and general education. …

Measurement Of The Cross-Sectional Area Of The Nasal Passages Of Nine Species Of Modern Odontoceti With Implications For Comparative Physiology And The Paleophysiology Of The Dinosauria, Eric Paul Katz

Dissertations and Theses

In search of evidence for or against the endothermic dinosaur hypothesis, a recent study by Ruben et al. (1996) revealed that endotherms tend to have larger nasal cross-sectional areas than ectotherms of the same mass. The reason offered for this observation was that larger nasal passages are needed to house the complex respiratory turbinates possessed by endotherms. Whales were excluded from the study on the grounds that they have no nasal turbinates. In the present study, the cross-sectional area of the nasal passages of nine species of Odontoceti were measured by the use of latex casts. The regression of log …

Internal Temperature Of Douglas-Fir Buds Is Altered At Elevated Temperature, Martha E. Apple, Melissa S. Lucash, David M. Olszyk, David T. Tingey, Donald L. Phillips

Environmental Science and Management Faculty Publications and Presentations

Pseudotsuga menziesii (Douglas-fir) saplings were grown in sun-lit controlled environment chambers at ambient or elevated (4°C above ambient) temperature. We measured internal temperatures of vegetative buds with thermocouple probes and compared temperatures of normal buds and abnormal buds with loosened, rosetted outer scales in elevated temperature chambers. The abnormal buds had higher and earlier peak daily temperatures than normal buds. Elevated temperature may influence the internal temperature of buds and contribute to the development of abnormal, rosetted buds with loosened outer scales. Abnormal bud development may alter branching patterns and allometry of Douglas-fir trees subjected to climatic change.

Sensory And Motor Interdependence In Postural Adjustments, Gin Mccollum

Gin McCollum

The sensory reafference from a movement depends upon the movement, and the movement chosen depends upon the available senses, as demonstrated by vestibular patients who abandon certain movements. Often, one variable is assumed to be dependent whereas the other is independent; however, sensory and motor dynamics in posture are interdependent as conditions upon each other. This paper applies conditional dynamics to characterize the global structure of interdependence between sensory states and motor strategies in fast postural adjustments. The mathematical formalism incorporates rich but disparate experimental, clinical, and theoretical results about sensory and motor control of posture.

The control structures presented …