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The DARPA Urban Challenge required robotic vehicles to travel more than 90 km through an urban environment without human intervention and included situations such as stop intersections, traffic merges, parking, and roadblocks. Team VictorTango separated the problem into three parts: base vehicle, perception, and planning. A Ford Escape outfitted with a custom drive-by-wire system and computers formed the basis for Odin. Perception used laser scanners, global positioning system, and a priori knowledge to identify obstacles, cars, and roads. Planning relied on a hybrid deliberative/reactive architecture to Robotics-2008 analyze the situation, select the appropriate behavior, and plan a safe path. All vehicle modules communicated using the JAUS (Joint Architecture for Unmanned Systems) standard. The performance of these components in the Urban Challenge is discussed and successes noted. The result of VictorTango's work was successful completion of the Urban Challenge and a third-place finish. C 2008 Wiley Periodicals, Inc.

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Branching ratios for H atom production from the reaction of CH(X2Π) with C2H2, C2H4, C2H6, and neo-C5H12 have been measured relative to that from the CH + CH4 reaction using laser-induced fluorescence at 121.56 nm (Lyman α). Assuming that the reaction with methane proceeds solely to the formation of H + C2H4, then the observed branching ratios are as follows:  C2H2 1.05 ± 0.09, C2H4 1.09 ± 0.14, C2H6 0.14 ± 0.06, and neo-C5H12 −0.10 ± 0.12 (errors refer to ±1σ). The results for the reaction of CH with acetylene and ethene are in good agreement with previous experimental and theoretical calculations. The yield of H atoms from the reaction of CH with ethane is consistent with a competition between C−H and C−C cleavage in an initially formed 1-propyl radical. The absence of H production for the reaction of CH with 2,2-dimethylpropane can be rationalized by the opening of isomerization pathways that lead to intermediates that dissociate only via C−C cleavage.

Radiopharmaceuticals containing the "fac-[M(CO)3]+ " core (M=99mTc, 186Re, or 188Re) have potential as diagnostic or therapeutic agents. Complexes with this core with sp3 amine donors have received little attention. We have studied adducts formed by ENDACH2 (HO2CCH2NHCH2CH2NHCH2CO2H) and ENACH (NH2CH2CH2NHCH2CO2H). Re(CO)3(ENDACH)-A (1A) and Re(CO)3(ENDACH)-B (1B) isomers were obtained by the reaction of ENDACH2 with Re(CO)5Cl. Re(CO)3(ENAC) (2) was obtained by the reaction of ENACH with aqueous [Re(CO)3(H2O)3]+. From single-crystal X-ray data, the three new neutral complexes, 1A, 1B, and 2, have a six-coordinate, pseudo-octahedral Re center with facially coordinated carbonyl ligands. ENDACH- and ENAC- bind facially to Re through both amine nitrogens and one carboxyl oxygen, forming two five-membered chelate rings. The Re(CO)3(ENDACH) isomers have an uncoordinated, dangling -CH2CO2H group, which is an ideal coupling site for attachment to biomolecules. The isomers differ by the configuration of the NH center bearing this dangling group. The H atom of the amine (N2) is endo (near the carbonyl ligands in the basal plane) in 1A and exo (away from carbonyl ligands) in isomer 1B. Isomers reach equilibrium (1A:1B, 70:30) after 3 days at high pH. Density functional structure optimizations were performed for isolated molecules of the type Tc(I)/Re(I)(CO)3(N2O): [Re(CO)3(NH3)2(H2O)]+, [Tc(CO)3(NH3)2(H2O)]+, [Re(CO)3(EN)(H2O)]+ (EN, ethylenediamine), [Tc(CO)3(EN)(H2O)]+, and various models for 1A, 1B, and 2. The computed structures are in good agreement with the X-ray structures. The theoretical and experimental Re-N bond distances usually agree within 0.045 A. The total electronic energy values for the computed 1A and 1B models differ by 0.815 kcal mol(-1), giving an isomer ratio of 80:20, in good agreement with the 1A/1B ratio (70:30) found.