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Biomedical subjects

W Power

Publications and source records attributed to W Power.

9 recordsLinked to original sources
PubMed2006

Benchmarking quantum control methods on a 12-qubit system.

In this Letter, we present an experimental benchmark of operational control methods in quantum information processors extended up to 12 qubits. We implement universal control of this large Hilbert space using two complementary approaches and discuss their accuracy and scalability. Despite decoherence, we were able to reach a 12-coherence state (or a 12-qubit pseudopure cat state) and decode it into an 11 qubit plus one qutrit pseudopure state using liquid state nuclear magnetic resonance quantum information processors.

Journal Article↗
PubMed2001

Patient pain during different stages of phacoemulsification using topical anesthesia.

PURPOSE: To assess the pain experienced by patients during the different stages of phacoemulsification cataract surgery performed under topical anesthesia. SETTING: Ophthalmic teaching hospital, Dublin, Ireland. METHODS: This prospective study comprised 100 consecutive patients having phacoemulsification under topical anesthesia. Patients were asked to grade the pain they experienced during the different stages of the procedure using a visual analog pain scale from 0 to 10. The pain experienced during the procedure was compared with that experienced after the instillation of a drop of amethocaine. RESULTS: The overall mean pain score was 1.46. The highest mean pain score, which was during the phacoemulsification stage of the procedure, was not significantly more than the score for the administration of the topical anesthetic agent. The duration of surgery was not related to the level of pain during the procedure. CONCLUSIONS: Topical anesthesia was effective in phacoemulsification cataract surgery. Because the highest mean score was not significantly higher than that for the administration of the anesthetic agent, it is possible to counsel patients before surgery that the pain they experience during the procedure will be no worse than that during administration of the anesthetic drops.

Adult↗
PubMed1993

Morphological appearances of human lens epithelial cells in culture.

A system for culturing human lens epithelial cells in the laboratory was developed. The morphological appearances of the cells was studied using phase contrast, scanning and transmission electron microscopy. Cell marker studies using monoclonal antibodies to cytokeratin, vimentin and epithelial membrane antigen were also performed. There was a marked increase in cell size as a function of time in culture. After 3 to 4 weeks cells showed early signs of ageing. By 6 to 8 weeks the majority of the cells had become very irregular in shape and demonstrated irregularities of the plasma membrane and intra-cytoplasmic vacuole formation. The cells stained strongly for vimentin and epithelial membrane antigen. Staining with cytokeratin was somewhat weaker. This culture technique provides us with a suitable model for studying the growth behavior of these cells.

Antibodies, Monoclonal↗
PubMed1993

Growth characteristics of human lens epithelial cells in culture. Effect of media and donor age.

The effect of different concentrations of fetal calf serum (FCS) on the proliferative capacity of human and bovine lens epithelial cells in culture was evaluated. The effect of donor age on the maximum number of passages achieved using thirty eight individual cultures was also studied. The donor ages ranged from 1-88 years. Fifteen percent FCS was found to be the optimum concentration for both human and bovine cells. The two cell types demonstrated very similar responses across the spectrum of concentrations used. Correlation analysis revealed a significant (p < 0.05) negative correlation between donor age and maximum number of cell passages achieved.

Adolescent↗
PubMedDate not supplied

Topical ciprofloxacin in the treatment of blepharitis and blepharoconjunctivitis.

An international multicentre study assessed the clinical and antibacterial efficacy of a new topical ophthalmic formulation of the quinolone antimicrobial agent ciprofloxacin and compared it with that of tobramycin ophthalmic solution in patients with blepharitis and blepharoconjunctivitis. The study consisted of a randomised double-masked between-group evaluation of 464 patients, 230 of whom were treated with ciprofloxacin and 234 with tobramycin. There was qualitative and quantitative bacteriology, and clinical assessment of ocular symptoms and signs before and after a seven-day course of treatment. Bacteriological cultures demonstrated eradication or reduction of potentially pathogenic bacteria in 93.7% of eyes (ciprofloxacin) versus 88.9% of eyes (tobramycin), seven days after starting treatment. Clinically more than 80% of patients in both treatment groups were cured or improved after seven days. No statistically significant differences were observed between the two treatment groups. No serious side-effects were observed after use of either antimicrobial agent. Ciprofloxacin ophthalmic solution appears safe and effective. The spectrum of activity and clinical efficacy of this new formulation are discussed in comparison with currently used antimicrobial agents.

Administration, Topical↗
PubMedDate not supplied

Pseudohypohyperparathyroidism: a case study of differential resistance to parathyroid hormone.

OBJECTIVE: To present a rare case of a combination of hyperparathyroidism and hypoparathyroidism in a 30-year-old woman. METHODS: We review the laboratory, radiographic, and pathologic findings in a healthy-appearing woman who sustained a patellar fracture after a simple fall at home. RESULTS: Our patient had features of hypoparathyroidism--that is, tetanic crises and hypocalcemia--and also hyperparathyroidism--fracture of the patella, multiple bone cysts, and confirmed osteitis fibrosa cystica on bone biopsy specimens. These features were associated with a high serum level of intact parathyroid hormone (PTH) and parathyroid hyperplasia. A lack of response of nephrogenic cyclic adenosine monophosphate (cAMP) to PTH stimulation was observed along with subnormal serum cAMP responses. In contrast, urine phosphate excretion increased after administration of PTH. CONCLUSION: These results demonstrate a state of renal PTH resistance in a patient with osteitis fibrosa cystica.

Journal Article↗