CCN

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In science and technology

Organizations

Conn Aerodrome

Conn Aerodrome (TC LID: CCN4) is located 3.6 nautical miles (6.7 km; 4.1 mi) east Conn, Ontario, Canada.

Visiting Aircraft information:

Mandatory radio frequency is 123.400MHz, call "Conn Traffic" within 5km of the airfield.

Aerodrome is visually referenced at the intersection of the 3 rows of high voltage transmission lines where they cross highway 89, Conn Aerodrome is directly north of this intersection. This is a privately owned aerodrome, home to the Toronto Soaring Club, and it operates primarily on weekends but does operate occasionally during the week in the summer months. Power traffic generally uses the circuit opposite to the glider traffic, but call in your intentions regardless. Gliders usually release from tow at 2000'AGL and enter the circuit at 1000'AGL. There is on-going training at the club and gliders will thermal in close proximity to the airfield to the underside of the airspace limit, so special attention is required if transiting the airspace.

The club uses a winch on occasion to launch gliders to an altitude of approximately 1100'-1200'AGL. The cable is nearly invisible to passing traffic, but drops quickly to the ground after being released from the glider. Generally winch launches occur in the autumn as the club prefers aerotow for launches.

Cyclin A2

Cyclin-A2 is a protein that in humans is encoded by the CCNA2 gene. It is one of the two types of cyclin A: cyclin A1 is expressed during meiosis and embryogenesis while cyclin A2 is expressed in dividing somatic cells.

Function

Cyclin A2 belongs to the cyclin family, whose members regulate cell cycle progression by interacting with CDK kinases. Cyclin A2 is unique in that it can activate two different CDK kinases; it binds CDK2 during S phase, and CDK1 during the transition from G2 to M phase.

Cyclin A2 is synthesized at the onset of S phase and localizes to the nucleus, where the cyclin A2-CDK2 complex is implicated in the initiation and progression of DNA synthesis. Phosphorylation of CDC6 and MCM4 by the cyclin A2-CDK2 complex prevents re-replication of DNA during the cell cycle.

Cyclin A2 is involved in the G2/M transition but it cannot independently form a maturation promoting factor (MPF). Recent studies have shown that the cyclin A2-CDK1 complex triggers cyclin B1-CDK1 activation which results in chromatin condensation and the breakdown of the nuclear envelope.