Publications by authors named "S Krasnicki"

Article Synopsis
  • Small-angle X-ray scattering (SAXS) studies were conducted on high-quality single-crystal CVD diamonds with low nitrogen levels, produced via microwave plasma-assisted chemical vapor deposition.
  • The 500 µm-thick undoped diamonds exhibited exceptional optical quality, allowing them to be effective windows for SAXS experiments with minimal unwanted scattering.
  • A successful application of these diamond windows was demonstrated in a high-pressure SAXS cell, showcasing their usefulness in advanced scientific research.
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Approaches for enhancing the strength and toughness of single-crystal diamond produced by chemical vapor deposition (CVD) at high growth rates are described. CVD processes used to grow single-crystal diamond in high density plasmas were modified to incorporate boron and nitrogen. Semi-quantitative studies of mechanical properties were carried out using Vickers indentation techniques.

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Single crystal diamond produced by chemical vapor deposition (CVD) at very high growth rates (up to 150 microm/h) has been successfully annealed without graphitization at temperatures up to 2200 degrees C and pressures <300 torr. Crystals were annealed in a hydrogen environment by using microwave plasma techniques for periods of time ranging from a fraction of minute to a few hours. This low-pressure/high-temperature (LPHT) annealing enhances the optical properties of this high-growth rate CVD single crystal diamond.

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Neuropeptide Y (NPY) and peptide YY (PYY) stimulate food intake after injection into the fourth cerebral ventricle, suggesting that NPY receptors in the hindbrain are targets for the stimulatory effect of these peptides on food intake. However, the NPY/PYY receptor subtype mediating the feeding response in the hindbrain is not known. To approach to this question we compared dose-effect of several NPY receptor agonists to stimulate food intake in freely-feeding rats 60- and 120-min after injection into the fourth cerebral ventricle.

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Background: Abnormalities in central neurotransmitter systems have been described in alcohol-dependent individuals and may contribute to alcohol craving. This study compared cerebrospinal fluid (CSF) levels of monoamine metabolites and beta endorphin levels in samples from early-onset alcohol-dependent patients (n = 20), late-onset alcohol-dependent patients (n = 14), and healthy controls (n = 23). It also evaluated whether these CSF measures levels predicted the degree of craving experienced in response to an alcohol cue.

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