1,588 research outputs found

    Bored with point and click?

    Get PDF
    Computers have the potential to be exploited as one of the most exciting examples of instructional media. Yet designers often fail to realize this potential. This is, in part, due to the limitations of hardware and software and, in part, due to the lack of good theory developed through conclusive research. Good examples of computer-based learning may owe more to the imaginative flair of the courseware designer than they do to the application of explicit design guidelines and good learning theory. This paper will therefore consider a variety of issues that may be blocking theoretical development and draw conclusions for future courses of action. This starts with a statement of the problem, first by considering the macro and micro issues, and then by looking at a recent call for help in ComputerBased Learning Environment (CBLE) design. Next, the contribution of instructional design theories will be presented together with a way forward for investigating the issues. Finally the implications for future progress are presented

    A proposed psychological model of driving automation

    Get PDF
    This paper considers psychological variables pertinent to driver automation. It is anticipated that driving with automated systems is likely to have a major impact on the drivers and a multiplicity of factors needs to be taken into account. A systems analysis of the driver, vehicle and automation served as the basis for eliciting psychological factors. The main variables to be considered were: feed-back, locus of control, mental workload, driver stress, situational awareness and mental representations. It is expected that anticipating the effects on the driver brought about by vehicle automation could lead to improved design strategies. Based on research evidence in the literature, the psychological factors were assembled into a model for further investigation

    The quality of life after liver transplantation

    Get PDF
    The quality of life after liver transplantation ranges from poor to superior. The social and vocational outcome is dependent on the quality of homograft function and on the steroid doses necessary to maintain function. A good long-term prognosis is usually evident by 1 year postoperatively. The complete rehabilitation of so many patients has encouraged us to continue our efforts in this difficult field

    Liver transplantation - 1978

    Get PDF
    The development of liver transplantation has been made difficult because of the enormous technical difficulties of the procedure and because the postoperative management in early cases was defective in many instances. With surgical and medical improvements, the prospects for success have markedly increased recently. The wider use of thoracic duct fistula as an adjuvant measure during the first 1 or 2 postoperative months is being explored

    The use of cyclosporin A and prednisone in cadaver kidney transplantation

    Get PDF
    Eighteen patients were treated with primary cadaveric renal transplantation using cyclosporin A therapy, and four more patients underwent cadaveric retransplantation. Eleven of the 22 recipients were conditioned with lymphoid depletion before transplantation, using thoracic duct drainage or lymphapheresis for two to eight and one-half weeks. cyclosporin A was begun a few hours before grafting. The other 11 patients were pretreated wtih cyclosporin A for from one day to 18 days. After transplantation, the majority of patients in both subgroups of 11 had rejection develop, but in most, the immunologic process was readily controlled with relatively small dosages of prednisone. After follow-up periods of two to four and one-half months, one patient has died of the complications of a coronary artery reconstruction that was not related to the transplantation. Another graft was lost from rejection, and a third organ was removed because of ureteral necrosis. Nineteen of the original 22 cadaveric kidneys are functioning, including 17 of the 18 kidneys given to patients who were undergoing transplantation for the first time. The only loss in the latter group of 18 patients was in the patient who died after an open heart operation. Results of these studies have shown that cyclosporin A is a superior and safe immunosuppressive drug but that, for optimal use in cadaveric transplantation, it usually should not be given alone. Steroid therapy greatly amplified the value of cyclosporin A. Unless major delayed morbidity develops which is not obvious so far, this drug combination should permit revolutionary advances ion the transplantation of all organs. Other adjunct to the cyclosporin A-steroid combination, including lymphoid depletion techniques, will require further investigation

    Liver replacement for pediatric patients

    Get PDF
    Between March 1963 and January 1978, 74 patients 18 years of age or younger have had liver replacements at the University of Colorado Medical Center, Denver. The most common cause of native liver failure was biliary atresia (48/74, 65%); the second most common cause was chronic aggressive hepatitis (12/74, 16%). Twenty-nine patients (39%) lived for at least one year, and 16 are still alive one to nine years after transplantation. Technical surgical problems, rejection, and infection were the main causes of death. Improved immunosuppression is needed; nevertheless, the quality of life in the long-term survivors has encouraged continuation of this difficult work

    Comparative analysis of enzymatically produced novel linear DNA constructs with plasmids for use as DNA vaccines

    Get PDF
    The use of DNA to deliver vaccine antigens offers many advantages, including ease of manufacture and cost. However, most DNA vaccines are plasmids and must be grown in bacterial culture, necessitating elements which are either unnecessary for effective gene delivery (e.g. bacterial origins of replication) or undesirable (e.g. antibiotic resistance genes). Removing these elements may improve the safety profile of DNA for the delivery of vaccines. Here we describe a novel, double-stranded, linear DNA construct produced by an enzymatic process that solely encodes an antigen expression cassette, comprising antigen, promoter, polyA tail and telomeric ends. We compared these constructs (called ‘Doggybones’ because of their shape) with conventional plasmid DNA. Using luciferase-expressing constructs, we demonstrated that expression levels were equivalent between Doggybones and plasmids both in vitro and in vivo. When mice were immunized with DNA constructs expressing the HIV envelope protein gp140, equivalent humoral and cellular responses were induced. Immunizations with either construct type expressing haemagluttinin were protective against H1N1 influenza challenge. This is the first example of an effective DNA vaccine which can be produced on a large scale by enzymatic processes

    Teachers use of fear appeals prior to a high-stakes examination: Is frequency linked to perceived student engagement and how do students respond?

    Get PDF
    Prior to high-stakes examinations teachers use messages that focus on the importance of avoiding failure (fear appeals). This study examined whether teacher use of fear appeals was related to their perceptions of student engagement, followed by students’ interpretation of fear appeals, and how they related to student-reported engagement. Teachers used more frequent fear appeals when they perceived student engagement to be low. More frequent fear appeals resulted in stronger challenge and threat appraisals. A challenge appraisal was associated with greater, and a threat appraisal with lower, behavioural and emotional engagement. Student appraisal seems to determine the effectiveness of these messages. © 2016 Elsevier Lt
    • …
    corecore