Shuttle/GPSPAC experimentation study

The utilization is discussed of the GPSPAC, which is presently being developed to be used on the low altitude host vehicle (LAHV), for possible use in the shuttle avionics system to evaluate shuttle/GPS navigation performance. Analysis and tradeoffs of the shuttle/GPS link, shuttle signal interface requirements, oscillator tradeoffs and GPSPAC mechanical modifications for shuttle are included. Only the on-orbit utilization of GPSPAC for the shuttle is discussed. Other phases are briefly touched upon. Recommendations are provided for using the present GPSPAC and the changes required to perform shuttle on-orbit navigation

tert-Butyl (2S)-2-{3-[(R)-bis­(tert-but­oxy­carbon­yl)amino]-2-oxopiperidin-1-yl}-3-methyl­butano­ate1

The title compound, C24H42N2O7, is a chiral lactam-constrained amino acid with a six-membered ring backbone and isopropyl and tert-butyl ester side chains. The conformation of the six-membered ring can be described as a half chair, with two CH2 C atoms lying 0.443 (1) and −0.310 (1) Å out of the best plane of the other four atoms (mean deviation = 0.042 Å). Both N atoms are sp 2 hybridized, lying 0.0413 (9) and 0.067 (1) Å out of the planes defined by the three C atoms bonded to them. The absolute configuration was determined, based on resonant scattering of light atoms in Cu Kα radiation

2-Ferrocenyl-N-(6-methyl-2-pyrid­yl)benzamide

The title compound, [Fe(C5H5)(C18H15N2O)], a product of the reaction of 2-ferrocenylbenzoic acid and 2-amino-6-methyl­pyridine, crystallizes with two dissimilar mol­ecules in the asymmetric unit. In one mol­ecule, the picoline amide group is directed away from the 2-ferrocenylbenzene moiety (anti) whereas in the other, these are proximate (syn). In the crystal structure, mol­ecules aggregate into dimers via cyclic, asymmetric N—H⋯N inter­actions with graph set R 2 2(8), and are further augmented via intra­molecular C—H⋯O=C and inter­dimer C—H⋯π(arene) inter­actions. Dimers are linked into chains along the [102] direction via weak C—H⋯O hydrogen bonds

Inductive Game Theory and the Dynamics of Animal Conflict

Conflict destabilizes social interactions and impedes cooperation at multiple scales of biological organization. Of fundamental interest are the causes of turbulent periods of conflict. We analyze conflict dynamics in an monkey society model system. We develop a technique, Inductive Game Theory, to extract directly from time-series data the decision-making strategies used by individuals and groups. This technique uses Monte Carlo simulation to test alternative causal models of conflict dynamics. We find individuals base their decision to fight on memory of social factors, not on short timescale ecological resource competition. Furthermore, the social assessments on which these decisions are based are triadic (self in relation to another pair of individuals), not pairwise. We show that this triadic decision making causes long conflict cascades and that there is a high population cost of the large fights associated with these cascades. These results suggest that individual agency has been over-emphasized in the social evolution of complex aggregates, and that pair-wise formalisms are inadequate. An appreciation of the empirical foundations of the collective dynamics of conflict is a crucial step towards its effective management

7-(5-Methyl­sulfanyl-β-d-erythrofuran­osyl)-7H-pyrrolo­[2,3-d]pyrimidin-4-amine monohydrate (MT-tubercidin·H2O)

The title compound, C12H16N4O3S·H2O, which has potential as a possible anti­malarial drug, was studied when small deviations in melting points, for two differently aged preparations, were observed. The unexpected existence of a water mol­ecule of crystallization is considered to be the cause of this variation. The 7H-pyrrolo­[2,3-d]pyrimidine unit is very slightly puckered with a total puckering amplitude of 0.035 (2) Å; its mean plane makes an angle of 88.40 (12)° with the mean plane through the ribofuranosyl unit. In the crystal, the mol­ecules are bound by strong O—H⋯N and N—H⋯O hydrogen bonds, utilizing all available protons and linking mainly through the water of crystallization

Benzyl­sulfamide

The crystal of the title compound [systematic name: 4-(benzyl­amino)­benzene­sulfonamide], C13H14N2O2S, displays a hydrogen-bonded framework structure. Mol­ecules are doubly N—H⋯O hydrogen bonded to one another via their NH2 groups and sulfonyl O atoms. These inter­actions generate a hydrogen-bonded ladder structure parallel to the a axis, which contains fused R 2 2(8) rings. The NH group serves as the hydrogen-bond donor for a second set of inter­molecular N—H⋯O=S inter­actions

3α,4α-Ep­oxy-5α-androstan-17β-yl acetate

The title compound, C21H32O3, results from modifications of the A and D rings of the aromatase substrate androstenedione. Ring A adopts a conformation between 10β-sofa and 1α,10β half-chair. Rings B and C are in slightly flattened chair conformations. Ring D approaches a 13β-envelope conformation, probably due to the acet­oxy substituent, and shows a very short Csp 3—Csp 3 bond next to the epoxide ring, which is characteristic of 3–4 epoxides.

Polythia­zide

The crystal structure of the title compound, C11H13ClF3N3O4S3 (systematic name: 6-chloro-2-methyl-3-{[(2,2,2-trifluoro­eth­yl)sulfan­yl]meth­yl}-3,4-dihydro-2H-1,2,4-benzothia­diazine-7-sul­f­on­amide 1,1-diox­ide; CRN: 346–18–9), exhibits a two-dimensional network of hydrogen-bonded mol­ecules parallel to (01). The NH and NH2 groups act as donor sites and the sulfonyl O atoms as acceptor sites in N—H⋯O hydrogen bonds, and a C—H⋯O interaction also occurs. The thiadiazine ring adopts an envelope conformation with the N atom bonded to sulfur at the tip of the flap, and the methyl substituent is in an axial position

5α,6α-Ep­oxy-7-norcholestan-3β-yl acetate

The title cholestan, C28H46O3, was prepared by epoxidation of 7-norcholest-5-en-3β-yl acetate and crystallized by slow evaporation from an ethano­lic solution. All rings are trans fused. The 3β-acetate and the 17β-cholestane side chain are in equatorial positions. The mol­ecule is highly twisted due to its B-nor characteristic. A quantum chemical ab-initio Roothaan Hartree–Fock calculation of the equilibrium geometry of the isolated mol­ecule gives values for bond lengths and valency angles in close agreement with the experimental ones