Richard S. Perkins

Performance of the infrared microspectroscopy beamline at CAMD

The first infrared (IR) beamline at the Center for Advanced Microstructures and Devices (CAMD) at Louisiana State University has been successfully constructed and commissioned. The beamline features a simple optical design with a minimal number of optical components. A pair of mirrors, planar and toroidal, is utilized for extracting synchrotron radiation (50 and 15 mrad, in horizontal and vertical directions, respectively) from the bending magnet port to a diamond window located outside of the shielding wall. Synchrotron radiation is then collimated by an off-axis parabolic mirror and fed into a Thermo Nicolet Continuum microscope through a Thermo Nicolet Nexus 670 FT-IR spectrometer. The microscope’s performances with synchrotron-radiation and conventional-thermal sources were compared in the mid-IR spectral range (11700–400cm−1). Effective beam spot size at sample position of the microscope was measured to be 35×12μm2 (FWHM). It was also determined that synchrotron radiation has substantial advantages o...

Synthesis, structure, and electrochemistry of mer[RuCl3(DMSO–S)(DMSO–O)(py)]

Reaction of mer-[RuCl3(DMSO–S)2(DMSO–O] (1) with pyridine (py) in dichloromethane yields mer-[RuCl3(DMSO–S)(DMSO–O)(py)] (2). A single crystal suitable for X-ray diffraction was obtained by recrystalization with dichloromethane and diethyl ether. X-ray diffraction analysis revealed an unusual case in which two independent molecules (2a and 2b) are present in the asymmetric unit cell. Both molecules have distorted octahedral geometry in which DMSO is bound through oxygen and sulfur. Density functional theory (DFT) calculations were performed for 2a and 2b in gas phase to investigate bonding shown by the two DMSO ligands. Optimizations were done on both DMSO ligands bonded through S, both DMSO ligands bonded through O, one DMSO bonded through O, and the other through S but opposite to the actual molecule. The energy differences of the optimized structures were calculated.

Raman spectroscopy of iron in aqueous carbonate solutions

Surface-enhanced Raman spectroscopy is used for in situ study of an iron surface in aqueous carbonate solutions both on open circuit and at constant potentials. Raman signals are assigned to FeCO3 and adsorbed water. Formation of FeCO3 corresponds to lowering of iron dissolution.

Ru(III)–TMSO complexes containing azole-based ligands: synthesis and cytotoxicity study

The reaction of mer-[RuCl3(S-TMSO)2(O-TMSO)] (TMSO = tetramethylene sulfoxide) with azoles (pyrazole = pzH and 3,5-dimethylpyrazole = dmpzH) in dichloromethane produced the complexes mer-[RuCl3(S-TMSO)(pzH)2] 1, mer-[RuCl3(S-TMSO)(O-TMSO)(pzH)] 2, mer-[RuCl3(S-TMSO)(dmpzH)2] 3, and mer-[RuCl3(S-TMSO)(O-TMSO)(dmpzH)] 4. These complexes were characterized using analytical, spectroscopic, and electrochemical techniques, as well as single-crystal X-ray diffraction analysis. Cytotoxicity assays on NB-Nu-39, a human neuroblastoma cell line, revealed that compounds 3 and 4, bearing methyl groups at the 3- and 5-positions of the pyrazole ring, exhibited significant cytotoxic activity towards neuroblastoma cells with IC50 values of 14.5 μM and 12.9 μM, respectively. The IC50 value of NAMI-A was 12.4 μM, which is very close to that of 4. In contrast, compounds 1 and 2 exhibited no appreciable cytotoxic activity towards neuroblastoma cells (IC50 ≫ 100 μM). The lipophilicity of complexes 1–4 was measured by the shake-flask method to obtain the partition coefficient. These studies reveal that lipophilicity may be a determining factor in the anticancer activity and pharmacological behavior of these Ru(III) complexes.

Raja yoga meditation and medication-assisted treatment for relapse prevention: A pilot study

The continued need for advancement in evidence-based SUD treatment, as well as increases in treatment expense and decline in support from insurance providers, suggest that brief, innovative, and affordable treatments are needed. Meditation, spirituality, and adherence to medication-assisted treatments have all been shown to support abstinence. The current trial assessed effects of spiritually-based meditation, versus relaxation or standard treatment, on substance abstinence and psychological distress and dysfunction in a partially buprenorphine-supported (41.5%) treatment sample. Participants (N = 40) were recruited from an intensive outpatient treatment program, in which three treatment locations acted as separate experimental conditions. Abstinence was measured through urinalyses at baseline and weekly thereafter for the duration of the intervention. Psychological distress and dysfunction were assessed with a Likert-scaled questionnaire measuring symptoms typically associated with SUD. Co-varying for buprenorphine use, participants in the Meditation condition had better odds of remaining abstinent than participants in the Treatment-as-Usual (TAU) and Relaxation conditions. There were no significant differences in substance abstinence between the Relaxation and TAU conditions. Further, co-varying out baseline there were no significant differences at post-course in psychological distress and dysfunction between the three conditions. Results from this pilot trial suggest that this spiritually-informed approach may offer additive support to individuals in SUD treatment, as an aid to the meditative aspect of the 12 steps, or a non-12-step alternative spiritual supplement to standard SUD treatment.