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Synchrotron Fourier transform infrared (FT-IR) spectra of fixed single erythrocytes infected with Plasmodium falciparum at different stages of the intraerythrocytic cycle are presented for the first time. Bands assigned to the hemozoin moiety at 1712, 1664, and 1209 [cm.sup.-1] are observed in FT-IR difference spectra between uninfected erythrocytes and infected trophozoites. These bands are also found to be important contributors in separating the trophozoite spectra from the uninfected cell spectra in principal components analysis. All stages of the intraerythrocytic lifecycle of the malarial parasite, including the ring and schizont stage, can be differentiated by visual inspection of the C--H stretching region (3100-2800 [cm.sup.-1]) and by using principal components analysis. Bands at 2922, 2852, and 1738 [cm.sup.-1] assigned to the [v.sub.asym](C[H.sub.2] acyl chain lipids), [v.sub.sym](C[H.sub.2] acyl chain lipids), and the ester carbonyl band, respectively, increase as the parasite matures from its early ring stage to the trophozoite and finally to the schizont stage. Training of an artificial neural network showed that excellent automated spectroscopic discrimination between P. falciparum-infected cells and the control cells is possible. FT-IR difference spectra indicate a change in the production of unsaturated fatty acids as the parasite matures. The ring stage spectrum shows bands associated with cis unsaturated fatty acids. The schizont stage spectrtun displays no evidence of cis bands and suggests an increase in saturated fatty acids. These results demonstrate that different phases of the P. falciparum intraerthyrocytic life cycle are characterized by different lipid compositions giving rise to distinct spectral profiles in the C-H stretching region. This insight paves the way for an automated infrared-based technology capable of diagnosing malaria at all intraerythrocytic stages of the parasite's life cycle.

The mechanism of reversible alkyne coupling at zirconium is examined by investigating the kinetics of zirconacyclopentadiene cleavage to produce free alkynes. The rates are shown to be largely affected by the steric properties of the ancillary ligands.

The fabrication of highly monodispersed platinum nanocubes by the decomposition of a platinum precursor in a hydrogen atmosphere is described. The observations and technique would provide opportunities for the formation of monodispersed faceted nanocrystals and their assembly into future devices.

The study is conducted in respect to the molecular and generic approach to establish roles for PKA and EP2 receptors in the desensitization of beta-agonist-mediated signaling and function in airway smooth muscle (ASM). This resulted in attenuation of both agonist-specific as well as cytokine-induced heterologous desensitization of the beta(sub 2)AR in ASM cells, through modulation of multiple targets, beta(sub 2)AR, adenylyl cyclase and COX-2 for the effective inhibition of PKA.

Monodisperse 1-2 nm silicon nanocrystals are synthesized in reverse micelles and have their surfaces capped with either allylamine or 1-heptene to produce either hydrophilic or hydrophobic silicon nanocrystals. Optical characterization is performed on colloidal solutions with the two types of surface-capped silicon nanocrystals with identical size distributions.

A low-temperature grafting approach using two Cu(super I) molecular precursors ([CuOSi(O(super t)Bu)3](sub 4) and [CuO(super t)Bu](sub 4) and a high-temperature exchange reaction using CuCl were utilized with a mesoporous silica support (SBA-15). This was done to investigate the effects of catalyst preparation on the nature of copper-support interactions and site speciation.

The synthesis and structural properties of three new hydridorhodium(III) complexes are reported. Using characterization techniques it was shown, that these features were attributed to the presence of weak pi-type eta(super 1)-arene interactions.

The effect of the mixed-ring silyl methyl complex in bromobenzene-d5 resulted in the zwitterionic hafnium silyl structure, which is constant for a minimum of 12 h in the solution. It is the omicron-bond metathesis is quite significant in the creation of novel catalytic alterations.

The synthesis of scandium alkyl Cp*2ScCH2CMe3 is done by the addition of a pentane solution of LiCH2CMe3 to Cp*2ScCl at low temperature. High selectivity toward methane activation suggest the participation of the chemistry in a catalytic hydromethylation, which is observed in the slow, Cp*2ScMe-catalyzed addition of methane across the double bond of propene to form isobutane.

The effects of electron-withdrawing perfluoroaryl groups on the zirconocene coupling of alkynes are described. Mechanistic studies on zirconocene couplings indicate that the observed regioselectivities are determined by an electronic factor that controls the orientation of at least one of the two alkynes as they are coupled.

The mechanism of samarium-mediated redistribution at silicon and chemoselectivity in sigma-bond metathesis reactions are discussed. This emphasizes the importance of electronic factors that control Si-C versus Si-H activation in organo-f-element systems and also establishes the factors that control selectivity in reactions of electrophilic lanthanide complexes with organosilanes and their potential relevance to analogous processes involving hydrocarbons.

Linear oligophenylene diynes containing 6, 9, and 12 phenylene rings are synthesized in high yields using the nucleophilic aromatic substitution (S(sub N)Ar) of perfluoroarenes by aryllithium reagents as the key carbon-carbon bond-forming reaction. It was noted that the diynes synthesized by this methodology were readily zirconocene-coupled into larger dimeric macrocycles using the zirconocene reagent Cp(sub 2)Zr(py)(Me(sub 3)SiC triple bond CSiMe(sub 3)).

Large, functionalized macrocycles were achieved using a new zirconocene-coupling route.

Research has been conducted on the P-glycoprotein and the multidrug resistance protein (MPR). Results indicate that MPR mediates the cytoxic natural product transport.