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Biomedical subjects

G Hornby

Publications and source records attributed to G Hornby.

7 recordsLinked to original sources
PubMed2001

Three generations of automatically designed robots.

The difficulties associated with designing, building, and controlling robots have led their development to a stasis: Applications are limited mostly to repetitive tasks with predefined behavior. Over the last few years we have been trying to address this challenge through an alternative approach: Rather than trying to control an existing machine or create a general-purpose robot, we propose that both the morphology and the controller should evolve at the same time. This process can lead to the automatic design of special-purpose mechanisms and controllers for specific short-term objectives. Here we provide a brief review of three generations of our recent research, which underlies the robots shown on the cover of this issue: Automatically designed static structures, automatically designed and manufactured dynamic electromechanical systems, and modular robots automatically designed through a generative DNA-like encoding.

Computer-Aided Design↗
PubMed1999

Probing the ligand-binding domain of the mGluR4 subtype of metabotropic glutamate receptor.

Metabotropic glutamate receptors (mGluRs) are G-protein-coupled glutamate receptors that subserve a number of diverse functions in the central nervous system. The large extracellular amino-terminal domains (ATDs) of mGluRs are homologous to the periplasmic binding proteins in bacteria. In this study, a region in the ATD of the mGluR4 subtype of mGluR postulated to contain the ligand-binding pocket was explored by site-directed mutagenesis using a molecular model of the tertiary structure of the ATD as a guiding tool. Although the conversion of Arg(78), Ser(159), or Thr(182) to Ala did not affect the level of protein expression or cell-surface expression, all three mutations severely impaired the ability of the receptor to bind the agonist L-[(3)H]amino-4-phosphonobutyric acid. Mutation of other residues within or in close proximity to the proposed binding pocket produced either no effect (Ser(157) and Ser(160)) or a relatively modest effect (Ser(181)) on ligand affinity compared with the Arg(78), Ser(159), and Thr(182) mutations. Based on these experimental findings, together with information obtained from the model in which the glutamate analog L-serine O-phosphate (L-SOP) was "docked" into the binding pocket, we suggest that the hydroxyl groups on the side chains of Ser(159) and Thr(182) of mGluR4 form hydrogen bonds with the alpha-carboxyl and alpha-amino groups on L-SOP, respectively, whereas Arg(78) forms an electrostatic interaction with the acidic side chains of L-SOP or glutamate. The conservation of Arg(78), Ser(159), and Thr(182) in all members of the mGluR family indicates that these amino acids may be fundamental recognition motifs for the binding of agonists to this class of receptors.

Amino Acid Sequence↗
PubMed1984

Behavioural group training with parents of mentally retarded children.

Seven parents of moderately mentally retarded children participated in a behavioural group training programme. Parents were taught to apply behavioural procedures to the specific problems presented by their children. A pre-test and post-test experimental design was used. A battery of outcome measures was employed, including observations of the parent-child interaction in the home environment. Although the results were somewhat mixed, in general the parents indicated that the programme was helpful and improved their knowledge of behavioural principles. Some positive changes in parent-child interaction at home were also observed.

Adolescent↗
PubMedDate not supplied

Group programmes for parents of children with various handicaps.

Programmes were conducted with groups of parents of school-aged, physically handicapped, hearing impaired, and, mildly and moderately mentally handicapped children. In this paper the salient features of the organization of these parent programmes are discussed. Programmes have involved six to eight weekly 2 hour sessions. The format of each session included both lecture presentation and discussion in small groups. Discussions were led by educational psychologists using a combination of reflective and behavioural procedures. Evaluation, by means of post-programme questionnaires and attendance checks, has shown that parents have found programmes to be valuable. An integral part of the parent programmes has been the training of special education teachers in the attitudes and skills necessary for working with parents of handicapped children. The introduction of group programmes is considered to complement the individual training and counselling services already available to such parents in New Zealand.

Adolescent↗
PubMedDate not supplied

Group training for parents of mentally retarded children: a review and methodological analysis of behavioural studies.

Behavioural group training studies with parents of mentally retarded children were reviewed, with a special emphasis on methodology. While all studies reported favourable training outcome, the lack of certain methodological controls demands that the results of these studies be interpreted with caution. Several methodological refinements are proposed in this paper and it is suggested that the group training modality offers a more economical and practical approach than individual parent training.

Adolescent↗
PubMedDate not supplied

Establishing a Parent to Parent service.

A Parent to Parent service has been established in Auckland to provide assistance to parents of children with disabilities. Parents who themselves have children with special needs undergo training to prepare them to support other parents. The Auckland scheme is a telephone counselling service which has been set up through cooperation between parents and professionals in the field of special education. Steps in the establishment of the scheme are described, the training course is outlined and various issues regarding the scheme are discussed. After 3 years of operation the Auckland Parent to Parent Service is well established and has developed a model of operation which has been used to set up similar schemes in various other centres around New Zealand. It is intended that this article be of assistance to other groups considering setting up Parent to Parent schemes.

Child↗