Experiences of Using a Public Key Infrastructure for the Preparation of Examination Papers

A project that piloted the secure electronic preparation of examination papers ran during the first semester of the academic year 1998-99 at the University of Salford. The examination papers were transferred between the participants (lecturers, administrators and external examiners) using secure electronic mail. Security was provided by a managed public key infrastructure. Users were profiled and interviewed in order to determine the likely success of further roll out within the institution, as well as the user friendliness of the existing paper based and proposed electronic systems. The project found that, while the technology worked for some participants, others had severe problems with installation of the software and failed to grasp key concepts. There appear to be formidable obstacles to extending the system to cover the whole university, including compatibility of equipment and the reliability of the network infrastructure

A 40 year old woman with cough, progressive dyspnea and bilateral lung opacities

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Transbronchial needle aspiration (TBNA) in the early diagnosis and staging of bronchogenic carcinoma.

Transbronchial needle aspiration (TBNA) has evolved as a useful technique to establish diagnosis in patients suspected of having bronchogenic carcinoma.Transbronchial needle aspiration (TBNA) was done in twenty-five patients with either proved or suspected bronchogenic carcinoma using a flexible bronchoscope. Results of 19 patients who had pulmonary malignancy were analysed.In the 12 patients with endobronchially visible abnormality, TBNA could correctly identify eleven patients with carcinoma and one patient, who was a treated case, with no evidence of residual disease. In the seven patients with bronchoscopically invisible extrabronchial disease, TBNA could identify four patients with malignancy and also characterize true negative disease in a treated case with subcarinal lymph node. TBNA could define the correct cytology in all the patients with visible tumours and in 59\% of patients with bronchoscopically invisible tumours. The procedure was diagnostic in 84\% of the cases. Mediastinal lymph node sampling in nine patients by TBNA, with the help of contrast enhanced CT scans, was positive in five patients and negative in the other four patients thus helping in nodal staging.Although the sample size of the study was small, the procedure was found to be very useful for the early diagnosis and staging of bronchogenic carcinoma. It was safe, well tolerated and no untoward complications were observed

Allergic BronchoPulmonary Aspergillosis in Nepal

Allergic BronchoPulmonary Aspergillosis is clinically under recognized and often misdiagnosed in Nepal. A total of 15 cases of ABPA were enrolled in this case series. Cases were followed up after the 3 months of start of treatment and clinical responses were assessed. The mean age of the patients was 33.06 ± 9.2 yrs. 80% were male. 26.6% patients were empirically on antitubercular treatment at the time of presentation. 40% patients were misdiagnosed and already treated as pulmonary Tuberculosis. 10 patients were previously treated as cases of refractory asthma. Majority of patients had significant eosinophillia and raised total serum IgE. All patients required treatment with bronchodilator and systemic steroid. 80% patients underwent remission with the treatment. Pulmonary Tuberculosis and refractory bronchial asthma are common condition that leads to the misdiagnosis of this disease.  Keywords: ABPA; bronchial asthma; central bronchiectasis; eosinophil count; serum IgE

Trusted Archiving

Digital signatures are a powerful tool for demonstrating data integrity and performing source authentication. Timestamps are a powerful tool for confirming data existence by a particular point in time. Today, the value of digital signatures (and timestamps containing digital signatures) is limited due to a lack of tools and techniques that address the problems associated with digital signatures that accrue over time, including: expiration, revocation, cryptanalytic advances and computational advances. In this paper, we describe a system concept and protocol to achieve secure storage of data for long periods with preservation of integrity. The approach uses periodically refreshed time stamps to address these problems. The techniques can be used for a wide variety of applications, including those requiring long-term non-repudiation of digital signatures. The concept and protocol are based on minimizing trust in individual system components in order to reduce the security requirements for those components and to enhance the trust in the overall system. A proof-of-concept implementation based on the ideas and protocol described in this paper has been developed and successfully tested. 1