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H Burns

Publications and source records attributed to H Burns.

33 records · Page 2Linked to original sources
PubMed1988

Knowledge-based educational systems.

In knowledge-based educational systems, the key concept is that information and procedures are represented in the same data structure. These structures can search for each other in flexible and, consequently, very robust ways. At the Air Force Human Resources Laboratory (AFHRL), our researchers are building computer environments that know what they know, know how people can best use them, and know how to draw inferences about their state--self-referential electronic tutors. In September 1986, artificial intelligence researchers participated in AFHRL's Research Planning Forum for Intelligent Tutorial Systems (ITS). This essay reviews the state of the philosophy, art, and science of artificial intelligence (AI) approaches to education. Then it summarizes the research issues which were presented, discussed, and better defined in this Forum--namely the nature and representation of 1) expertise modules, 2) student diagnostic modules, 3) adaptive instructional and curriculum modules, 4) instructional environments, and 5) man-machine interfaces. Advances in artificial intelligence, cognitive science, and instructional discourse have provided a means for investigating human learning, for representing an individual's own "knowledge processing." Research and development in knowledge-based educational systems seems promising, not only for helping people learn how to perform complex tasks, but also for explicitly expressing how people learn to learn. Therefore, would it not be wise to establish a scientific legacy for the development of effective knowledge-based tutorial systems which is informed by the best studies of mind and meaning, language and thought, purpose and paradox?

Artificial Intelligence↗
PubMed1984

N-nitrosodimethylamine carcinogenesis in nicotinamide-deficient rats.

Special diets that were extremely low in protein (5.5%) and high in carbohydrate were used to test the effect of nicotinamide on N-nitrosodimethylamine-induced carcinogenesis in Holtzman albino rats. The level of nicotinamide in the three diets ranged from 0 mg/kg of food to 50 mg/kg to 500 mg/kg. During the treatment with these diets (5 weeks) and the carcinogen (18 days), the renal and hepatic concentrations of nicotinamide adenine dinucleotide-reduced nicotinamide adenine dinucleotide and nicotinamide adenine dinucleotide phosphate-reduced nicotinamide adenine dinucleotide phosphate were measured. In the liver, the concentration of these coenzymes fell well below normal levels, and significant differences between the two extreme diets (0 and 500 mg/kg) were found in the hepatic content of nicotinamide adenine dinucleotide-reduced nicotinamide adenine dinucleotide. In the kidney, the treatment with special diets and carcinogen had less effect. The content of nicotinamide adenine dinucleotide phosphate-reduced nicotinamide adenine dinucleotide phosphate remained normal, and the only significant drop in the concentrations of nicotinamide adenine dinucleotide-reduced nicotinamide adenine dinucleotide phosphate occurred in the animals on the nicotinamide-deficient diet. After the treatment, all of the animals were returned to the same standard diet. During the remainder of the experiment, 85 weeks, it was found that the initial treatments had not affected tumor incidence levels or tumor type, but had altered the rate of tumor incidence. These differences could be seen by comparing the results for the rats that had been given the nicotinamide-deficient diet to the results for the animals receiving an excess of the vitamin.

Animals↗
PubMed1983

Malignant external otitis in a young diabetic patient.

A case of malignant external otitis in a young diabetic is reported. This entity should be suspected in diabetics of all ages and in all immune-deficient patients presenting with aural discharge, associated with a dehiscence of the meatal wall, meatal granulations or post-aural abcess. Gentamicin/Carbenicillin combination obviated the need for major surgery.

Adult↗
PubMed1979

Conservation surgery in laryngeal cancer and its role following failed radiotherapy. A histopathological and clinical study of 32 cases.

The partial laryngectomy specimens from 32 patients with laryngeal carcinoma were histologically examined by the technique of whole organ sectioning. Twenty-three of these patients had previous irradiation therapy. We identify local criteria for performing conservation laryngeal surgery based on clinical and histopathological studies. These criteria are borne out as success or failure, and outcome could be accurately predicted when adhered to. The salvage rate for patients receiving conservation surgery after failed radiotherapy was 60%, while 43% retained a functional larynx.

Adenocarcinoma↗
PubMed1977

Surgery and histopathology of the stapes in osteogenesis imperfecta tarda.

Fourteen stapedectomies were performed on ten patients with osteogenesis imperfecta tarda. Clinically, the footplates were softer and more tenuously fixed than in otosclerosis and floating footplates seemed more common. Stapes and stapes fragments from all 14 operations were examined microscopically. The histopathology of osteogenesis imperfecta was contrasted to that of otosclerosis. We believe that the greater degree of structural disorganization and greater area occupied by resorption spaces clearly distinguish the new bone formed in osteogenesis imperfecta from otosclerosis.

Adolescent↗
PubMed1975

Capillary basement membrane width in diabetic children.

The effect of juvenile onset diabetes mellitus on quadriceps muscle capillary basement membrane (QCBM) width has been examined by the electron microscopic morphometric method previously developed in this laboratory. The results demonstrate that in this age group QCBM thickening is strongly related to the age of the diabetic subject. As a result, in contrast to the almost constant thickening of QCBM that has consistently been documented in diabetic adults, QCBM hypertrophy is present in only 40 per cent of children with diabetes mellitus. As was previously shown to be the case in adults, in children, too, QCBM thickening is unrelated to the duration of the diabetes. Finally, the finding that QCBM hypertrophy is present at the time of acute onset of juvenile diabetes mellitus in 30 per cent of children, coupled with the fact that this lesion is not affected by duration of hyperglycemia, strongly supports our previous conclusion that diabetic microangiopathy is independent of the hyperglycemia of this disease. On the other hand, barring the possibility that microangiopathy in the pancreas precedes that in muscle, these results represent evidence against the suggestion that basement membrane hypertrophy represents the primary lesion of the diabetic syndrome.

Adolescent↗
PubMedDate not supplied

Malignant sinonasal tumours: the Dublin Eye and Ear Hospital experience.

We identified 51 patients from pathology and operative records who were treated in the Royal Victoria Eye and Ear Hospital with malignant sinonasal tumours between January 1980 and December 1991. Complete follow up was available in 43 patients. There were 30 males, mean age 50 years, range (10-80) and 13 females, mean age 59 years, range (34-75). Commonest presentations were nasal obstruction, nasal discharge and facial swelling. Patients presented late because of initial non specific symptoms. The maxilla was the site of origin in 18 patients, the ethmoids in 13 patients and the nasal cavity in 12 patients. There was a wide range of histological types with squamous cell carcinoma occurring in 19 patients (44%). All patients were treated with surgery, radiotherapy or a combination of both. Chemotherapy was used as an adjunctive therapy in three patients. Local recurrence occurred in 21 (50%) of the patients. Overall three year survival was 58% and five year survival was 45%. These figures compare favourably with larger series in the literature. A high index of suspicion, early recognition and referral of these patients is required to improve survival.

Adolescent↗