Software and hardware implementation of the RSA public key cipher

Cryptographic systems and their use in communications are presented. The advantages obtained by the use of a public key cipher and the importance of this in a commercial environment are stressed. Two two main public key ciphers are considered. The RSA public key cipher is introduced and various methods for implementing this cipher on a standard, nondedicated, 8 bit microprocessor are investigated. The performance of the different algorithms are evaluated and compared. Various ways of increasing the performance are considered. The limitations imposed by the performance on the practical use of the cipher are discussed. The importance of the key to the security of the cipher is assessed. Different forms of attack are mentioned and a procedure for generating keys, which minimise the probability of a sucessful attack is presented. This procedure is implemented on a minicomputer. Use of the method on personal computers or microprocessors is examined. Methods for performing multiplication in hardware, with particular emphasis on the use of these methods in modular multiplication, are detailed. An algorithm for performing part of the encryption function in hardware and the hardware necessary for it is described. Different methods for implementing the hardware are discussed and one is choosen. A description of the hardware unit is given. The design and development of an application specific integrated circuit (ASIC) to perform key elements of the encryption function is described. The various stages of the design process are detailed. The results expected from this device and its integration into the overall encryption scheme are presented

Autoxidation of 2-Naphthols

This thesis describes an investigation of the structural factors which influence the susceptibility of substituted 2-naphthols to autoxidation. The mechanism of these processes is discussed in detail in the light of the results obtained. Previous workers had found that 2-naphthols containing a-branched alkyl substituents at C-1 (ethyl, isopropyl, cyclohexyl) autoxidise readily under extremely mild conditions, the overall rate being greater for those containing bulkier substituents. 2-Naphthols containing small substituents at C-1 (H, methyl, benzyl) do not autoxidise at an appreciable rate. It is proposed that the major factor controlling the overall rate of autoxidation of substituted 2-naphthols is the degree of steric strain within the molecule, and especially the magnitude of the peri-interaction between substituents at C-1 and C-8. This peri-interaction is absent in the l-alkyl-l-hydroperoxy-2(1H)-naphthalenones (1) produced in the autoxidation reactions. The resulting strain relief is thought to be the factor controlling the overall autoxidation rates. I set out to prepare a range of 2-naphthols incorporating a variety of structural features which may elucidate the factors influencing the autoxidation rates, and to study the relative rates in a semi-quantitative manner. Several unknown naphthols which autoxidise rapidly under extremely mild conditions have been prepared, viz. 1-t-butyl- and l-t-pentyl-2-naphthol, 1-methyl-3,6-di-t-butyl-2-naphthol, 1,8-dimethyl-2-naphthol, and l-isopropyl-6-bromo-2-naphthol. Autoxidation of these compounds was found to give the corresponding hydroperoxides (1) in high yield. Several unknown naphthols which are stable to oxygen have also been prepared. A consideration of the results obtained shows conclusively that the autoxidation rates of 2-naphthols is indeed a function mainly of steric strain, electronic factors being of secondary importance. Two plausible mechanistic interpretations are proposed. It is thought that the reaction of the intermediate 2-naphthoxy radicals with molecular oxygen may be the rate-determining step, since this involves the removal of the unfavourable peri-interaction, or that the phenolic O-H bond may be weakened as a result of molecular distortions, thus facilitating the abstraction of hydrogen from the naphthol by the intermediate peroxy radical. Some of the anomalous spectroscopic and chemical behaviour of the compounds under investigation are also related to steric compression

Forensic dentistry in Cork

An important role of the forensic dentist is in the identification of the deceased. Dental identification has proved to be extremely useful and reliable and is quicker and less expensive than DNA identification. The identification of individuals missing for prolonged periods can bring closure to family members and allow burial of the remains. The objective of this poster is to describe the application of forensic dentistry in Cork University Hospital to identify human remains over a three year period

Dental anxiety prevalence and surgery environment factors: A questionnaire-based survey of attenders in Ireland

Aim: To identify and quantify anxious dental patientsand dental office environment factors that may influence anxiety. Objective: To develop and implement a questionnaire toinvestigate dental anxiety and identify factors thatenhance or lessen dental anxiety in the surgery setting. Methods: Data was collected from patients by a self completed questionnaire when attending dentists at a general dental practice and hospital clinics. Results: The estimated prevalence of dental anxiety in the totalsample was 17.0%. A higher proportion of females were highly anxious. Those attending the Dental Hospital were less likely to be anxious than those who were attending the Dental Practice. An inverse relationship between frequency of dental attendance and dental anxiety was found. Anxiety was significantly higher forthose respondents that indicated that a delay in their appointment would make them more anxious. Of the reported fears regarding their dental visit, 60% of respondents claimed that they were afraid it s going tohurt . When compared to non-anxious patients, more anxious patients feared feeling out of control , a negative experience , the needle, the drill, and being bothered by the smell associated with dental materials.The majority of respondents had a preference for a dentist that was young, friendly, talkative and native English speaking. In general, patients preferred the surgery temperature to be slightly cool. Regardless of anxiety level, 31.0% of patients said that they would prefer the chairside mouth rinse to be plain water with 49.1% not having a preference. Conclusions: This study demonstrates that a significant proportion of patients experience anxiety about visiting the dentist. Many of them have preferences about dentists and the surgery environment which may be modulators of their anxiety. Awareness by the dental profession of the causes of dental anxiety and measures taken by dentists tominimise these trigger factors could have a substantial impact on anxious patients

Erwinia oleae sp. nov., isolated from olive knots caused by Pseudomonas savastanoi pv. savastanoi

Three endophytic bacterial isolates were obtained in Italy from olive knots caused by Pseudomonas savastanoi pv. savastanoi. Phenotypic tests in combination with 16S rRNA gene sequence analysis indicated a phylogenetic position of these isolates in the genus Erwinia or Pantoea, and revealed two other strains with highly similar 16S rRNA gene sequences (> 99 %), CECT 5262 and CECT 5264, obtained in Spain from olive knots. Rep-PCR DNA fingerprinting of the five strains from olive knots with BOX, ERIC and REP primers revealed three groups of profiles that were highly similar to each other. Multilocus sequence analysis (MLSA) based on concatenated partial atpD, gyrB, infB and rpoB gene sequences, indicated that the strains constitute a single novel species in the genus Erwinia. The strains showed general phenotypic characteristic of Erwinia, and whole genome DNA-DNA hybridization data confirmed they represent a single novel Erwinia species. The strains showed a DNA G+C base composition ranging from 54.7 to 54.9 mol%. They could be discriminated from the phylogenetically related Erwinia species by their ability to utilise potassium gluconate, L-rhamnose and D-arabitol, but not glycerol, inositol and D-sorbitol. The name Erwinia oleae (type strain DAPP-PG 531T = LMG 25322T = DSM 23398T) is proposed for this new taxon

Assessing the Spoofing Threat: Development of a Portable GPS Civilian Spoofer

A portable civilian GPS spoofer is implemented on a digital signal processor and used to characterize spoofing effects and develop defenses against civilian spoofing. This work is intended to equip GNSS users and receiver manufacturers with authentication methods that are effective against unsophisticated spoofing attacks. The work also serves to refine the civilian spoofing threat assessment by demonstrating the challenges involved in mounting a spoofing attack.Aerospace Engineering and Engineering Mechanic

Analyzing the Carbon Footprint of an Intravitreal Injection

Purpose: To estimate the carbon footprint of a single intravitreal injection in a hospital-based intravitreal service. Methods: Greenhouse gas emissions attributable to the delivery of an intravitreal injection were calculated using a hybrid lifecycle analysis technique. Data were collected regarding procurement of materials, patient travel, and building energy use. Results: Carbon emissions associated with a single intravitreal injection, excluding the anti-VEGF agent, were 13.68 kg CO2eq. This equates to 82,100 kg CO2eq annually for our service. Patient travel accounted for the majority of emissions at 77%, with procurement accounting 19% for and building energy usage for 4% of total emissions. The omission of items considered dispensable from injection packs would reduce carbon emissions by an estimated 0.56 kg per injection – an annual saving of 3,360 kg CO2eq for our service. Similar savings, if extrapolated to a country the size of the United Kingdom, could yield annual carbon savings of 450,000 kg CO2eq. For context, a single one-way economy transatlantic flight produces 480 kg CO2eq per person. Conclusion: Wasteful practice in healthcare increases greenhouse gas production and drives climate change. The healthcare sector should be a leader in sustainable practice promotion and changes to high volume procedures have the largest impact on emissions. Long-acting agents offer the greatest future potential for meaningful reductions

Parapneumonic empyema diagnosed by chest radiograph and computed tomography

Pleural effusion is commonly seen associated with pneumonia. When this progresses to empyema, directed therapy is frequently required. Chest radiographic and computed tomography findings can help distinguish empyema from a transudative pleural effusion