Modeling and Verification of Privacy Enhancing Protocols

Privacy enhancing protocols (PEPs) are a family of protocols that allow secure exchange and management of sensitive user information. They are important in preserving users’ privacy in today’s open environment. Proof of the correctness of PEPs is necessary before they can be deployed. However, the traditional provable security approach, though well established for verifying cryptographic primitives, is not applicable to PEPs. We apply the formal method of Coloured Petri Nets (CPNs) to construct an executable specification of a representative PEP, namely the Private Information Escrow Bound to Multiple Conditions Protocol (PIEMCP). Formal semantics of the CPN specification allow us to reason about various security properties of PIEMCP using state space analysis techniques. This investigation provides us with preliminary insights for modeling and verification of PEPs in general, demonstrating the benefit of applying the CPN-based formal approach to proving the correctness of PEPs.

Information interventions for orienting patients and their carers to cancer care facilities (Protocol)

To assess the effects of information interventions which orient patients and their carers/family to a cancer care facility and the services available in the facility.

A grounded theory study of nursing students’ experiences in the off-campus clinical setting

Poor workplace relations are an issue of concern in many workplaces and this phenomenon is not restricted to the nursing profession. The issue of workplace violence in nursing is well documented and there are an increasing number of studies which have investigated the notion of horizontal violence amongst graduate nurses. The impact that poor workplace relations has on the development of a professional identity by nursing students in the off-campus clinical setting is significant in light of the current global shortage of nurses. There is a dearth of knowledge in understanding how Australian undergraduate nursing students experience the off-campus clinical setting and subsequently develop a professional identity as a nurse. Therefore the aim of this study was to discover and describe the phenomena in order to develop a substantive theory that explains the experiences of the undergraduate nursing students in a regional setting. Constructivist grounded theory methods were utilised in the conduct of the study. A sample of 29 participants was recruited permitting the formulation of a substantive theory regarding the development of a professional identity in nursing students. This substantive theory contributes knowledge relevant to the undergraduate nursing students, nurse educators, nursing workforce planners, and the tertiary educational institutions offering nursing. This is achieved through discovering, describing and explaining the phenomenon of ‘anxiety’ which the nursing students experience as a result of the interrelationship and interactions of tradition bearing, staff and student performance. These interactions intersect to form expectations of where the student fits within the hierarchy of the facility and the nursing profession in general. An understanding of the issues associated with tradition bearing, staff performance, and student performance and the impact that the interaction of these conditions has upon the student’s developing professional identity as a nurse is necessary to allow for the implementation of corrective strategies.

Clinical whole-body skin examination reduces the incidence of thick melanomas

Survival from melanoma is strongly related to tumour thickness, thus earlier diagnosis has the potential to reduce mortality from this disease. However, in the absence of conclusive evidence that clinical skin examination reduces mortality, evidence-based assessments do not recommend population screening. We aimed to assess whether clinical whole-body skin examination is associated with a reduced incidence of thick melanoma and also whether screening is associated with an increased incidence of thin lesions (possible overdiagnosis). A population-based case-control study of all Queensland residents aged 20-75 years with a histologically confirmed first primary invasive cutaneous melanoma diagnosed between January 2000 and December 2003. Telephone interviews were completed by 3,762 eligible cases (78.0%) and 3,824 eligible controls (50.4%) Whole-body clinical skin examination in the three years before diagnosis was associated with a 14% lower risk of being diagnosed with a thick melanoma (>0.75mm) (OR= 0.86, 95% CI=0.75, 0.98). Risk decreased for melanomas of increasing thickness: the risk of being diagnosed with a melanoma 0.76-1.49mm was reduced by 7% (OR=0.93, 95% CI 0.79, 1.10), by 17% for melanomas 1.50-2.99mm (OR=0.83, 95% CI=0.65, 1.05) and by 40% for melanomas ≥3mm (OR=0.60, 95% CI=0.43, 0.83). Screening was associated with a 38% higher risk of being diagnosed with a thin invasive melanoma (≤0.75mm) (OR=1.38, 95% CI=1.22, 1.56). This is the strongest evidence to date that whole-body clinical skin examination reduces the incidence of thick melanoma. Because survival from melanoma is strongly related to tumour thickness, these results suggest that screening would reduce melanoma mortality.

Protein complementation assay as a display system for screening protein libraries in the intracellular environment

A wide range of screening strategies have been employed to isolate antibodies and other proteins with specific attributes, including binding affinity, specificity, stability and improved expression. However, there remains no high-throughput system to screen for target-binding proteins in a mammalian, intracellular environment. Such a system would allow binding reagents to be isolated against intracellular clinical targets such as cell signalling proteins associated with tumour formation (p53, ras, cyclin E), proteins associated with neurodegenerative disorders (huntingtin, betaamyloid precursor protein), and various proteins crucial to viral replication (e.g. HIV-1 proteins such as Tat, Rev and Vif-1), which are difficult to screen by phage, ribosome or cell-surface display. This study used the β-lactamase protein complementation assay (PCA) as the display and selection component of a system for screening a protein library in the cytoplasm of HEK 293T cells. The colicin E7 (ColE7) and Immunity protein 7 (Imm7) *Escherichia coli* proteins were used as model interaction partners for developing the system. These proteins drove effective β-lactamase complementation, resulting in a signal-to-noise ratio (9:1 – 13:1) comparable to that of other β-lactamase PCAs described in the literature. The model Imm7-ColE7 interaction was then used to validate protocols for library screening. Single positive cells that harboured the Imm7 and ColE7 binding partners were identified and isolated using flow cytometric cell sorting in combination with the fluorescent β-lactamase substrate, CCF2/AM. A single-cell PCR was then used to amplify the Imm7 coding sequence directly from each sorted cell. With the screening system validated, it was then used to screen a protein library based the Imm7 scaffold against a proof-of-principle target. The wild-type Imm7 sequence, as well as mutants with wild-type residues in the ColE7- binding loop were enriched from the library after a single round of selection, which is consistent with other eukaryotic screening systems such as yeast and mammalian cell-surface display. In summary, this thesis describes a new technology for screening protein libraries in a mammalian, intracellular environment. This system has the potential to complement existing screening technologies by allowing access to intracellular proteins and expanding the range of targets available to the pharmaceutical industry.

Public health and clinical dilemmas resulting from imprecise vitamin D tests

Objective: To determine whether there are clinical and public health dilemmas resulting from the reproducibility of routine vitamin D assays. Methods: Blinded agreement studies were conducted in eight clinical laboratories using two commonly used assays to measure serum 25-hydroxyvitamin D (25(OH)D) levels in Australasia and Canada (DiaSorin Radioimmunoassay (RIA) and DiaSorin LIAISON® one). Results: Only one laboratory measured 25(OH)D with excellent precision. Replicate 25(OH)D measurements varied by up to 97% and 15% of paired results differed by more than 50%. Thirteen percent of subjects received one result indicating insufficiency [25-50 nmol/l] and another suggesting adequacy [>50 nmol/l]). Agreement ranged from poor to excellent for laboratories using the manual RIA, while the precision of the semi-automated Liaison® system was consistently poor. Conclusions: Recent interest in the relevance of vitamin D to human health has increased demand for 25(OH)D testing and associated costs. Our results suggest clinicians and public health authorities are making decisions about treatment or changes to public health policy based on imprecise data. Clinicians, researchers and policy makers should be made aware of the imprecision of current 25(OH)D testing so that they exercise caution when using these assays for clinical practice, and when interpreting the findings of epidemiological studies based on vitamin D levels measured using these assays. Development of a rapid, reproducible, accurate and robust assay should be a priority due to interest in populationbased screening programs and research to inform public health policy about the amount of sun exposure required for human health. In the interim, 25(OH)D results should routinely include a statement of measurement uncertainty.

Building the toolkit of quality monitoring clinical outcomes as a means of assessing quality in residential care

Residential aged care in Australia does not have a system of quality assessment related to clinical outcomes, creating a significant gap in quality monitoring. Clinical outcomes represent the results of all inputs into care, thus providing an indication of the success of those inputs. To fill this gap, an assessment tool based on resident outcomes (the ResCareQA) was developed and evaluated in collaboration with residential care providers. A useful output of the ResCareQA is a profile of resident clinical status, and this paper will use such outputs to present a snapshot of nine residential facilities. Such comprehensive data has not yet been available within Australia, so this will provide an important insight. ResCareQA data was collected from all residents (N=498) of nine aged care facilities from two major aged care providers. For each facility, numerator–denominator data were calculated to assess the degree of potential clinical problems. Results varied across clinical areas and across facilities, and rank-ordered facility results for selected clinical areas are reviewed and discussed. Use of the ResCareQA to generate clinical outcome data provides a concrete means of monitoring care quality within residential facilities; regular use of the ResCareQA could thus contribute to improved care outcomes within residential aged care.

Continuous infusion of ticarcillin-clavulanate for home treatment of serious infections : clinical efficacy, safety, pharmacokinetics and pharmacodynamics

Continuous infusion (CI) ticarcillin–clavulanate is a potential therapeutic improvement over conventional intermittent dosing because the major pharmacodynamic (PD) predictor of efficacy of β-lactams is the time that free drug levels exceed the MIC. This study incorporated a 6-year retrospective arm evaluating efficacy and safety of CI ticarcillin–clavulanate in the home treatment of serious infections and a prospective arm additionally evaluating pharmacokinetics (PK) and PD. In the prospective arm, steady-state serum ticarcillin and clavulanate levels and MIC testing of significant pathogens were performed. One hundred and twelve patients (median age, 56 years) were treated with a CI dose of 9.3–12.4 g/day and mean CI duration of 18.0 days. Infections treated included osteomyelitis (50 patients), septic arthritis (6), cellulitis (17), pulmonary infections (12), febrile neutropenia (7), vascular infections (7), intra-abdominal infections (2), and Gram-negative endocarditis (2); 91/112 (81%) of patients were cured, 14 (13%) had partial response and 7 (6%) failed therapy. Nine patients had PICC line complications and five patients had drug adverse events. Eighteen patients had prospective PK/PD assessment although only four patients had sufficient data for a full PK/PD evaluation (both serum steady-state drug levels and ticarcillin and clavulanate MICs from a bacteriological isolate), as this was difficult to obtain in home-based patients, particularly as serum clavulanate levels were found to deteriorate rapidly on storage. Three of four patients with matched PK/PD assessment had free drug levels exceeding the MIC of the pathogen. Home CI of ticarcillin–clavulanate is a safe, effective, convenient and practical therapy and is a therapeutic advance over traditional intermittent dosing when used in the home setting.

Enhancing transition : an enhanced model of clinical placement for final year nursing students

Specialised support for student nurses making the transition to graduate nurse can be crucial to successful and smooth adjustment, and can create a path to positive and stable career experiences. This paper describes an enhanced model of final year nursing student placements which was trialled in 2006 at the Queensland University of Technology. The model involved collaboration with two major urban health services and resources were developed to support effective transition experiences. Ninety-two students, including 29 trial participants and 63 non-trial participants were assessed on preparedness for professional practice, before and after the trial semester. Results indicated an increase in preparedness across the entire sample, but students participating in the trial did not differ significantly in overall preparedness change from those who did not participate. Higher baseline preparedness in the trial group highlighted the possibility that proactive students who choose enrichment experiences tend to be likelier to gain benefit from such options than those who do not. Qualitative findings from focus groups conducted with 12 transition group students highlighted that one of the main beneficial aspects of the experience for students was the sense of belonging to a team that understood their learning needs and could work constructively with them.

Clinical results in primary THR

Written by the surgeons of the Exeter Hip Team and their colleagues from around the world, this book describes 40 years of innovation and development with cemented hip replacement. Topics covered include the basic science behind successful cemented hip replacement, modern surgical techniques and recent advances. There is also extensive coverage of the revision techniques developed at Exeter and elsewhere, focussing on femoral and acetabular impaction grafting. Each chapter is a self-contained article with an emphasis, where appropriate, on practical techniques and surgical tips, supported by line drawings and intra-operative photographs.

Clinical results : Acetabular impaction grafting

Written by the surgeons of the Exeter Hip Team and their colleagues from around the world, this book describes 40 years of innovation and development with cemented hip replacement. Topics covered include the basic science behind successful cemented hip replacement, modern surgical techniques and recent advances. There is also extensive coverage of the revision techniques developed at Exeter and elsewhere, focussing on femoral and acetabular impaction grafting. Each chapter is a self-contained article with an emphasis, where appropriate, on practical techniques and surgical tips, supported by line drawings and intra-operative photographs.

Improved image contrast of the bone-muscle interface with 3T MRI compared to 1.5T MRI [Abstract]

Virtual 3D models of long bones are increasingly being used for implant design and research applications. The current gold standard for the acquisition of such data is Computed Tomography (CT) scanning. Due to radiation exposure, CT is generally limited to the imaging of clinical cases and cadaver specimens. Magnetic Resonance Imaging (MRI) does not involve ionising radiation and therefore can be used to image selected healthy human volunteers for research purposes. The feasibility of MRI as alternative to CT for the acquisition of morphological bone data of the lower extremity has been demonstrated in recent studies [1, 2]. Some of the current limitations of MRI are long scanning times and difficulties with image segmentation in certain anatomical regions due to poor contrast between bone and surrounding muscle tissues. Higher field strength scanners promise to offer faster imaging times or better image quality. In this study image quality at 1.5T is quantitatively compared to images acquired at 3T. --------- The femora of five human volunteers were scanned using 1.5T and 3T MRI scanners from the same manufacturer (Siemens) with similar imaging protocols. A 3D flash sequence was used with TE = 4.66 ms, flip angle = 15° and voxel size = 0.5 × 0.5 × 1 mm. PA-Matrix and body matrix coils were used to cover the lower limb and pelvis respectively. Signal to noise ratio (SNR) [3] and contrast to noise ratio (CNR) [3] of the axial images from the proximal, shaft and distal regions were used to assess the quality of images from the 1.5T and 3T scanners. The SNR was calculated for the muscle and bone-marrow in the axial images. The CNR was calculated for the muscle to cortex and cortex to bone marrow interfaces, respectively. --------- Preliminary results (one volunteer) show that the SNR of muscle for the shaft and distal regions was higher in 3T images (11.65 and 17.60) than 1.5T images (8.12 and 8.11). For the proximal region the SNR of muscles was higher in 1.5T images (7.52) than 3T images (6.78). The SNR of bone marrow was slightly higher in 1.5T images for both proximal and shaft regions, while it was lower in the distal region compared to 3T images. The CNR between muscle and bone of all three regions was higher in 3T images (4.14, 6.55 and 12.99) than in 1.5T images (2.49, 3.25 and 9.89). The CNR between bone-marrow and bone was slightly higher in 1.5T images (4.87, 12.89 and 10.07) compared to 3T images (3.74, 10.83 and 10.15). These results show that the 3T images generated higher contrast between bone and the muscle tissue than the 1.5T images. It is expected that this improvement of image contrast will significantly reduce the time required for the mainly manual segmentation of the MR images. Future work will focus on optimizing the 3T imaging protocol for reducing chemical shift and susceptibility artifacts.

Book review : "Community engagement in contemporary legal education : Pro Bono, Clinical legal education and services learning"

The result of a forum on community engagement held in November 2008 at Bond University, Community Engagement in Contemporary Legal Education is a compilation of papers presented at the forum by academics and professionals throughout Australia. Although found initially to be a topic of legal interest, it was not until the reviewer came across the Council of Australian Law Deans (CALD) “Standards for Australian Law Schools” (adopted 17 November 20093) then the full importance and potential of this book was revealed. Clause 2.2.4 of the CALD Standards recognises the importance of “experiential learning opportunities” for law students and cites examples such as clinical programs, internships, practical experience and pro-bono work. Clause 2.3.3 acknowledges the need to develop professional ethics and again cites pro-bono obligations as an example. Clause 9.6.2 encourages interaction of law schools with the profession and the community and again, pro-bono community service is identified as one method of doing so. Yet nowhere in the document are there any uniform standards or binding obligations that law schools must commit to. In the current climate where the importance of practical experience is continually emphasised and student numbers exceed the number of available paid legal positions, there should be more focus on the details of how these commitments should be converted to be included in a law school’s curriculum.

The relationship between deformity correction and clinical outcomes after thoracoscopic scoliosis surgery : a prospective series of 100 patients

The relationship between deformity correction and self-reported patient satisfaction after thoracoscopic anterior scoliosis surgery is unknown. Scoliosis Research Society questionnaire scores, radiographic outcomes, and rib hump correction were prospectively assessed for a group of 100 patients pre-operatively and at two years after surgery. Patients with lower post-op major Cobb angles report significantly higher SRS scores than patients with higher post-op Cobb angles.

Controversies of prophylactic hypothermia and the emerging use of brain tissue oxygen tension monitoring and decompressive craniectomy in traumatic brain-injured children

Background Despite being the leading cause of death and disability in the paediatric population, traumatic brain injury (TBI) in this group is largely understudied. Clinical practice within the paediatric intensive care unit (PICU) has been based upon adult guidelines however children are significantly different in terms of mechanism, pathophysiology and consequence of injury. Aim To review TBI management in the PICU and gain insight into potential management strategies. Method To conduct this review, a literature search was conducted using MEDLINE, PUBMED and The Cochrane Library using the following key words; traumatic brain injury; paediatric; hypothermia. There were no date restrictions applied to ensure that past studies, whose principles remain current were not excluded. Results Three areas were identified from the literature search and will be discussed against current acknowledged treatment strategies: Prophylactic hypothermia, brain tissue oxygen tension monitoring and decompressive craniectomy. Conclusion Previous literature has failed to fully address paediatric specific management protocols and we therefore have little evidence-based guidance. This review has shown that there is an emerging and ongoing trend towards paediatric specific TBI research in particular the area of moderate prophylactic hypothermia (MPH).