Reconstructing links in directed networks from noisy dynamics.

We address the long-standing challenge of how to reconstruct links in directed networks from measurements, and present a general method that makes use of a noise-induced relation between network structure and both the time-lagged covariance of measurements taken at two different times and the covariance of measurements taken at the same time. When the coupling functions have certain additional properties, we can further reconstruct the weights of the links.

Upper gastro-intestinal endoscopy for Chinese elderly in an acute geriatric unit: a review.

From December 1982 to August 1983, a total of 242 oesophago-gastro-duodenoscopies were performed for 208 elderly patients in the Geriatric Unit, Princess Margaret Hospital, Hong Kong. These were done as part of an investigatory procedure in the Geriatric Unit, the first of its kind in Hong Kong. In the 9-month survey, it was found that upper gastro-intestinal endoscopy is a safe and useful diagnostic investigation. It also provides in-service training and stimulation for staff working in the unit to look at one of the many facets of geriatric medicine.

Healing of gastric ulcer in the elderly: a double-blind study of cetraxate versus ranitidine.

Forty-nine Chinese patients, ages 65 years or over, with endoscopically and pathologically diagnosed benign gastric ulcer, completed a randomized double-blind double dummy trial in treatment with either cetraxate 200 mg four times daily or ranitidine 150 mg two times daily for 12 weeks or less if the gastric ulcer had completely healed. All patients tolerated the procedure well. At the end of the 4th, 8th, and 12th weeks ulcer healing was complete in 2 (8%), 11 (42%), and 17 (65%), respectively, of the cetraxate group (26 patients); and in 8 (35%), 18 (78%), and 22 (96%), respectively, of the ranitidine group (23 patients). All the differences in the healing rates were statistically significant. Pain relief was significantly earlier with ranitidine. Incidences of side effects were similar and not serious in the two groups. The results suggest that at the doses prescribed to the elderly, ranitidine is significantly more effective than cetraxate in gastric ulcer healing and pain relief.

Prospective study of drug reporting by general practitioners for an elderly population referred to a geriatric service.

A prospective study was carried out in which the drug history of patients which was provided by general practitioners was compared with the drugs found by geriatricians in patients' homes in 700 referrals to geriatricians. Drug compliance was not assessed. The drug history appeared to be accurate in one third of referrals. Underreporting of medication was common and increased as the number of prescribed drugs increased. Roughly one fifth of patients had at least one potential drug interaction. Keeping careful prescription records, regular review, and accurate reporting of medication should reduce drug associated morbidity in elderly patients.