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Alltop functions have applications to code-division multiple access (CDMA) systems and mutually unbiased bases (MUBs). Alltop functions construct MUBs and CDMA signal sets, and this motivates the continued search for further Alltop functions. The discovery of further Alltop functions is hindered by the computational complexity of verification. This paper narrows the search space through the introduction of a characteristic cubic polynomial and provides a verification process for Alltop monomials with a reduced computational complexity. Computational results lead to the conjecture that there are no further Alltop monomials.

The purpose of this study was to obtain a range of normal measurements of the adult thoracic aorta and main pulmonary artery using cardiac MRI, and to assess agreement between measurements made on ECG-gated two-dimensional (2D) breath held steady-state-free precession (SSFP), and three-dimensional (3D) breath held SSFP image acquisitions. Forty-nine normal volunteers underwent cardiac MRI using a 1.5T system. Two independent examiners measured the ascending aorta, aortic arch, descending thoracic aorta and main pulmonary artery in pre-defined locations. Overall, inter-observer agreement for all measurements was excellent. Close agreement was observed in aortic diameters obtained from the 2D and 3D SSFP methods in six of the nine aortic measurement sites. There was a tendency for the 3D measurements to be smaller than the 2D measurements but this was only significant at two sites, the aortic annulus, and the ascending aorta. There was a significance difference in aortic measurements between the left carotid artery (LC) and the left subclavian artery (LSC). Normal values for transverse diameters of the thoracic aorta and main pulmonary artery were established using 2D and 3D non-contrast MR sequences in healthy adults. Overall both inter-observer agreement, and agreement between 2D and 3D techniques was good. Mean diameter differences demonstrated at the aortic annulus, ascending aorta and aortic arch between LC and LSC although significant were less than one millimetre and unlikely to be important in clinical practice.

This paper investigates differential fault attacks against AEZ v4.2 authenticated encryption scheme. AEZ uses three different 128-bit keys (I, J, L) and can potentially work without a nonce or with a repeated nonce. Under these conditions, this paper identifies the best place to apply differential fault attacks. We exploit the structure of AEZ to minimise the total number of faults required for key recovery. We propose an approach that can reduce the number of fault injections required to retrieve all three AEZ keys, I, J and L, from six to four such that these keys are uniquely determined. As a second step, we further reduce the fault injections to three without reducing the success rate of the key recovery attack. This improvement to differential fault attacks on AEZ makes these attacks more practical. The attacks in this paper are verified experimentally using a generic implementation of AEZ v4.2 developed in C.

This study investigated particle and gaseous emission factors from a large cargo vessel for her whole voyage including at berth, manoeuvring and cruising. Quantification of these factors assists in minimising the uncertainty in the current methods of exhaust gas emission factor estimation. Engine performance and emissions from the main marine engine were measured on-board while the ship was manoeuvring and cruising at sea. Emissions of an auxiliary engine working at 55% of maximum continuous rating (MCR) were measured when the ship was at actual harbour stopovers. Gaseous and particle emission factors in this study are presented in g kWh-1 or # kWh-1, and compared with previous studies. Results showed that the SO2 emission factor is higher than that of previous studies due to the high sulphur content of the fuel used. The particle number size distributions showed only one mode for different operating conditions of the ship, with a peak at around 40-50 nm, which was dominated by ultrafine particles. Emission factors of CO, HC, PM and PN observed during ship manoeuvring were much higher than that of those recorded at cruising condition. These findings highlight the importance of quantification and monitoring ship emissions in close proximity to port areas, as they can have the highest impact on population exposure.

Non-linear feedback shift register (NLFSR) ciphers are cryptographic tools of choice of the industry especially for mobile communication. Their attractive feature is a high efficiency when implemented in hardware or software. However, the main problem of NLFSR ciphers is that their security is still not well investigated. The paper makes a progress in the study of the security of NLFSR ciphers. In particular, we show a distinguishing attack on linearly filtered NLFSR (or LF-NLFSR) ciphers. We extend the attack to a linear combination of LF-NLFSRs. We investigate the security of a modified version of the Grain stream cipher and show its vulnerability to both key recovery and distinguishing attacks.

This paper presents a model for the generation of a MAC tag using a stream cipher. The input message is used indirectly to control segments of the keystream that form the MAC tag. Several recent proposals can be considered as instances of this general model, as they all perform message accumulation in this way. However, they use slightly different processes in the message preparation and finalisation phases. We examine the security of this model for different options and against different types of attack, and conclude that the indirect injection model can be used to generate MAC tags securely for certain combinations of options. Careful consideration is required at the design stage to avoid combinations of options that result in susceptibility to forgery attacks. Additionally, some implementations may be vulnerable to side-channel attacks if used in Authenticated Encryption (AE) algorithms. We give design recommendations to provide resistance to these attacks for proposals following this model.

Free to read Aims To investigate associations between HMG-CoA reductase inhibitor (statin) use and muscle strength, balance, mobility and falls in older people. Methods Five hundred community-dwelling people aged 70–90 years provided information about their medication use and undertook tests of lower limb strength, postural sway, leaning balance (maximal balance range and coordinated stability tests) and functional mobility. Participants were then followed up for 12 months with respect to falls. Results After adjusting for general health in analyses of covariance procedures, statin users had poorer maximal balance range than non-statin users (P = 0.017). Statin and non-statin users did not differ with respect to strength, postural sway, mobility or falls experienced in the follow-up year. Conclusion In a sample of healthy older people, statin use was not associated with muscle weakness, postural sway, reduced mobility or falls. Statin users, however, had poorer leaning balance which may potentially increase fall risk in this group.

Objective: This retrospective, observational cohort study investigated whether the clinical features of a patient's pain, including anatomical location, organ system and likely treating speciality, impact on the delivery of analgesia within 30min in EDs. Methods: Data were obtained from 24 centres across Australia between April 2008 and March 2009. Principal outcome was delivery of analgesia within 30min or less. Factors that might explain any differences were analysed, including anatomical location of the pain, likely treating speciality, organ system affected, age, sex, day and time of presentation, hospital location, documented pain score and triage category. Analysis was by the χ -test for independence of proportions and multiple logistic regression. A P-value

The initialisation process is a key component in modern stream cipher design. A well-designed initialisation process should not reveal any information about the secret key, or possess properties that may help to facilitate attacks. This paper analyses the initialisation processes of shift register based stream ciphers and identifies four flaws which lead to compression, state convergence, the existence of slid pairs and possible weak Key-IV combinations. These flaws are illustrated using the A5/1 stream cipher as a case study. We also provide some design recommendations for the intialisation process in stream ciphers, to overcome these and other flaws.

Sfinks is a shift register based stream cipher designed for hardware implementation and submitted to the eSTREAM project. In this paper, we analyse the initialisation process of Sfinks. We demonstrate a slid property of the loaded state of the Sfinks cipher, where multiple key-IV pairs may produce phase shifted keystream sequences. The state update functions of both the initialisation process and keystream generation and also the pattern of the padding affect generation of the slid pairs.

This retrospective, observational cohort study investigated whether the clinical features of a patient's pain, including anatomical location, organ system and likely treating speciality, impact on the delivery of analgesia within 30 min in EDs.Data were obtained from 24 centres across Australia between April 2008 and March 2009. Principal outcome was delivery of analgesia within 30 min or less. Factors that might explain any differences were analysed, including anatomical location of the pain, likely treating speciality, organ system affected, age, sex, day and time of presentation, hospital location, documented pain score and triage category. Analysis was by the χ(2)-test for independence of proportions and multiple logistic regression. A P-value0.05 was considered statistically significant.There were 4598 patients, of whom 2578 were male. The median age was 36 years (range 0-103). Both limb origin of pain (χ(2) = 46.1, P0.001) and documentation of a pain score (χ(2) = 48.6, P0.001) were strongly associated with delivery of analgesia within 30 min. Attending a rural ED was a significant risk factor for delayed analgesia (χ(2) = 12.5, P0.001). Burns patients (40.2%, 47 of 117, P0.001) and orthopaedic patients (26.1%, 259 of 992, P0.001) were much more likely to received analgesia within 30 min than the mean (19.5%, 896 of 4598).Patients presenting with burns, orthopaedic conditions or with a limb location of pain are more likely to receive analgesia within 30 min in Australian EDs. Clinicians should be aware of possible trends in the delivery of timely analgesia to patients with pain.