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Discusses the joint statement signed by Presidents Clinton and Yeltsin on Mar. 21, 1997 on enlargement of the 1972 ABM Treaty to prohibit space based theater missile defenses (TMDs); critical of failure to draw a clear line between ABM and TMD systems.

It is contended that ballistic missile & missile defense technological advancements & increased security needs have created interest among American policymakers to revise the 1972 Anti-Ballistic Missile (ABM) Treaty. The impact of the Rumsfeld Commission's findings on the threat that ballistic missiles pose to national security & the growth of North Korea's ballistic missile program on missile defense technology are considered. A comparison of missile defense technology in 1972 & 2000 demonstrates that the ABM Treaty has placed severe constraints on US security. Specific technological improvements to the sensors & radar systems that guide interceptor missiles as well as changes to US political motivations for implementing a national missile defense system are then discussed. The benefits of creating land- & sea-based & boost phase interceptor theater missile defense systems for US security are contemplated. The Clinton administration's failure to revise the ABM Treaty to allow for theater missile defense is also covered. It is concluded that the ABM Treaty must be modernized to remain a viable agreement. 2 Figures. J. W. Parker

9 pages, 7 figures.-- PMID: 16766669 [PubMed].-- PMCID: PMC1533959.-- Printed version Aug 2006. ; Rumex palustris (polygonceae) responds to complete submergence with enhanced elongation of its youngest petioles. This process requires the presence of gibberellin (GA) and is associated with an increase in the concentration of GA1 in elongating petioles.We have examined how GAbiosynthesis was regulated in submerged plants. Therefore, cDNAs encoding GA-biosynthetic enzymes GA20-oxidase andGA3-oxidase, and the GA-deactivating enzymeGA2-oxidase were cloned from R. palustris and the kinetics of transcription of the corresponding genes was determined during a 24 h submergence period. The submergence-induced elongation response could be separated into several phases: (1) during the first phase of 4 h, petiole elongation was insensitive to GA; (2) from 4 to 6 h onward growth was limited by GA; and (3) from 15 h onward underwater elongation was dependent, but not limited by GA. Submergence induced an increase of GA1 concentration, as well as enhanced transcript levels of RpGA3ox1. Exogenous abscisic acid repressed the transcript levels of RpGA20ox1 and RpGA3ox1 and thus inhibited the submergence-induced increase in GA1. Abscisic acid had no effect on the tissue responsiveness to GA. ; This work was supported by the Dutch Science Foundation (PIONIER grant no. 800.84.470) and by a grant from the European Union (HPRM–CT–RTN1–2000–00090). ; Peer reviewed