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Our manuscript describes a SARS-CoV-2 outbreak investigation in an Ontario tertiary care hospital. We use traditional contract tracing paired with whole-genome sequencing to facilitate an understanding of the evolutionary history and transmission dynamics of this SARS-CoV-2 outbreak in a clinical setting.

Flare frequency distributions represent a key approach to addressing one of the largest problems in solar and stellar physics: determining the mechanism that counter-intuitively heats coronae to temperatures that are orders of magnitude hotter than the corresponding photospheres. It is widely accepted that the magnetic field is responsible for the heating, but there are two competing mechanisms that could explain it: nanoflares or Alfv\'en waves. To date, neither can be directly observed. Nanoflares are, by definition, extremely small, but their aggregate energy release could represent a substantial heating mechanism, presuming they are sufficiently abundant. One way to test this presumption is via the flare frequency distribution, which describes how often flares of various energies occur. If the slope of the power law fitting the flare frequency distribution is above a critical threshold, $\alpha=2$ as established in prior literature, then there should be a sufficient abundance of nanoflares to explain coronal heating. We performed $>$600 case studies of solar flares, made possible by an unprecedented number of data analysts via three semesters of an undergraduate physics laboratory course. This allowed us to include two crucial, but nontrivial, analysis methods: pre-flare baseline subtraction and computation of the flare energy, which requires determining flare start and stop times. We aggregated the results of these analyses into a statistical study to determine that $\alpha = 1.63 \pm 0.03$. This is below the critical threshold, suggesting that Alfv\'en waves are an important driver of coronal heating., Comment: 1,002 authors, 14 pages, 4 figures, 3 tables, published by The Astrophysical Journal on 2023-05-09, volume 948, page 71

The Comprehensive Antibiotic Resistance Database (CARD; card.mcmaster.ca) combines the Antibiotic Resistance Ontology (ARO) with curated AMR gene (ARG) sequences and resistance-conferring mutations to provide an informatics framework for annotation and interpretation of resistomes. As of version 3.2.4, CARD encompasses 6627 ontology terms, 5010 reference sequences, 1933 mutations, 3004 publications, and 5057 AMR detection models that can be used by the accompanying Resistance Gene Identifier (RGI) software to annotate genomic or metagenomic sequences. Focused curation enhancements since 2020 include expanded β-lactamase curation, incorporation of likelihood-based AMR mutations for Mycobacterium tuberculosis, addition of disinfectants and antiseptics plus their associated ARGs, and systematic curation of resistance-modifying agents. This expanded curation includes 180 new AMR gene families, 15 new drug classes, 1 new resistance mechanism, and two new ontological relationships: evolutionary_variant_of and is_small_molecule_inhibitor. In silico prediction of resistomes and prevalence statistics of ARGs has been expanded to 377 pathogens, 21,079 chromosomes, 2,662 genomic islands, 41,828 plasmids and 155,606 whole-genome shotgun assemblies, resulting in collation of 322,710 unique ARG allele sequences. New features include the CARD:Live collection of community submitted isolate resistome data and the introduction of standardized 15 character CARD Short Names for ARGs to support machine learning efforts.

Metabotropic glutamate receptor 4 (mGlu4) is one of eight mGlu receptors within the Class C G protein-coupled receptor superfamily. mGlu4 is primarily localized to the presynaptic membrane of neurons where it functions as an auto and heteroreceptor controlling synaptic release of neurotransmitter. mGlu4 is implicated in numerous disorders and is a promising drug target; however, more remains to be understood about its regulation and pharmacology. Using high-throughput sequencing, we have validated and quantified an adenosine-to-inosine (A-to-I) RNA editing event that converts glutamine 124 to arginine in mGlu4; additionally, we have identified a rare but novel K129R site. Using an in vitro editing assay, we then validated the pre-mRNA duplex that allows for editing by ADAR enzymes and predicted its conservation across the mammalian species. Structural modeling of the mGlu4 protein predicts the Q124R substitution to occur in the B helix of the receptor that is critical for receptor dimerization and activation. Interestingly, editing of a receptor homodimer does not disrupt G protein activation in response to the endogenous agonist, glutamate. Using an assay designed to specifically measure heterodimer populations at the surface, however, we found that Q124R substitution decreased the propensity of mGlu4 to heterodimerize with mGlu2 and mGlu7. Our study is the first to extensively describe the extent and regulatory factors of RNA editing of mGlu4 mRNA transcripts. In addition, we have proposed a novel functional consequence of this editing event that provides insights regarding its effects in vivo and expands the regulatory capacity for mGlu receptors.

The Cherenkov Telescope Array Observatory (CTAO) consists of three types of telescopes: large-sized (LST), mediumsized (MST), and small-sized (SST), distributed in two observing sites (North and South). For the CTA South "Alpha Configuration" the construction and installation of 37 (+5) SST telescopes (a number that could increase up to 70 in future upgrades) are planned. The SSTs are developed by an international consortium of institutes that will provide them as an in-kind contribution to CTAO. The SSTs rely on a Schwarzschild-Couder-like dual-mirror polynomial optical design, with a primary mirror of 4 m diameter, and are equipped with a focal plane camera based on SiPM detectors covering a field of view of ~9°. The current SST concept was validated by developing the prototype dual-mirror ASTRI-Horn Cherenkov telescope and the CHEC-S SiPM focal plane camera. In this contribution, we will present an overview of the SST key technologies, the current status of the SST project, and the planned schedule.

Axion-like-particles (ALPs) emitted from the core of a magnetar can convert to photons in its magnetosphere. The resulting photon flux is sensitive to the product of $(i)$ the ALP-nucleon coupling $G_{an}$ which controls the production cross section in the core and $(ii)$ the ALP-photon coupling $g_{a\gamma \gamma}$ which controls the conversion in the magnetosphere. We study such emissions in the soft-gamma-ray range (300 keV to 1 MeV), where the ALP spectrum peaks and astrophysical backgrounds from resonant Compton upscattering are expected to be suppressed. Using published quiescent soft-gamma-ray flux upper limits in 5 magnetars obtained with $CGRO$ COMPTEL and $INTEGRAL$ SPI/IBIS/ISGRI, we put limits on the product of the ALP-nucleon and ALP-photon couplings. We also provide a detailed study of the dependence of our results on the magnetar core temperature. We further show projections of our result for future $Fermi$-GBM observations. Our results motivate a program of studying quiescent soft-gamma-ray emission from magnetars with the $Fermi$-GBM., Comment: 14 pages, 4 figures. Version accepted in Physical Review D. More conservative benchmark core temperature assumed, details of production in the core provided, new constraints on ALP couplings based on spectral analysis presented. Extensive supplementary material added, future projections discussed, overall conclusions unchanged

The melanocortin peptides derived from pro-opiomelanocortin (POMC) were originally understood in terms of the biological actions of α-melanocyte-stimulating hormone (α-MSH) on pigmentation and adrenocorticotrophic hormone on adrenocortical glucocorticoid production. However, the discovery of POMC mRNA and melanocortin peptides in the CNS generated activities directed at understanding the direct biological actions of melanocortins in the brain. Ultimately, discovery of unique melanocortin receptors expressed in the CNS, the melanocortin-3 (MC3R) and melanocortin-4 (MC4R) receptors, led to the development of pharmacological tools and genetic models leading to the demonstration that the central melanocortin system plays a critical role in the regulation of energy homeostasis. Indeed, mutations in MC4R are now known to be the most common cause of early onset syndromic obesity, accounting for 2–5% of all cases. This review discusses the history of these discoveries, as well as the latest work attempting to understand the molecular and cellular basis of regulation of feeding and energy homeostasis by the predominant melanocortin peptide in the CNS, α-MSH.

Analysing 9 years of Fermi-LAT observations, we recently studied the spectral properties of the prominent globular cluster 47 Tuc (Brown et al. 2018). In particular, we investigated several models to explain the observed gamma-ray emission, ranging from millisecond pulsars (MSP) to Dark Matter (DM), with the motivation for the latter model driven by recent evidence that 47 Tuc harbours an intermediate-mass black hole (IMBH). This investigation found evidence that the observed gamma-ray emission from 47 Tuc is due to two source populations of MSPs and DM. In Bartels \& Edwards (2018), the authors comment that this evidence is an artifact of the MSP spectra used in (Brown et al. 2019). Here we reply to this comment and argue that the authors of Bartels \& Edwards (2018) (i) do not give due consideration to a very important implication of their result and (ii) there is tension between our MSP fit and their MSP fit when taking uncertainties into consideration. As such, we still conclude there is evidence for a DM component which motivates a deeper radio study of the prominent globular cluster 47 Tuc., 3 pages, accepted for publication in PRD

We analyze 9 years of PASS 8 $\textit{Fermi}$-LAT data in the 60$-$500 MeV range and determine flux upper limits (UL) for 17 gamma-ray dark pulsars as a probe of axions produced by nucleon-nucleon Bremsstrahlung in the pulsar core. Using a previously published axion decay gamma-ray photon flux model for pulsars which relies on a high core temperature of 20 MeV, we improve the determination of the UL axion mass ($m_a$), at 95 percent confidence level, to 9.6 $\times$ 10$^{-3}$ eV, which is a factor of 8 improvement on previous results. We show that the axion emissivity (energy loss rate per volume) at realistic lower pulsar core temperatures of 4 MeV or less is reduced to such an extent that axion emissivity and the gamma-ray signal becomes negligible. We consider an alternative emission model based on energy loss rate per mass to allow $m_a$ to be constrained with $Fermi$-LAT observations. This model yields a plausible UL $m_a$ of 10$^{-6}$ eV for pulsar core temperature $, Comment: 13 pages, 5 figures, Accepted for publication in Physical Review D

We analyse 8 years of PASS 8 Fermi-LAT data, in the 60 MeV - 300 GeV energy range, from 30 high Galactic latitude globular clusters. Six of these globular clusters are detected with a TS > 25, with NGC 6254 being detected as gamma-ray bright for the first time. The most significant detection is of the well-known globular cluster 47 Tuc, and we produce a refined spectral fit for this object with a log parabola model. NGC 6093, NGC 6752 and NGC 6254 are fitted with hard, flat power law models, NGC 7078 is best fitted with a soft power law and NGC 6218 is best fitted with a hard, broken power law. This variety of spectral models suggests that there is a variety of gamma-ray source types within globular clusters, in addition to the traditional millisecond pulsar interpretation. We identify a correspondence between diffuse X-ray emission in globular cluster cores and gamma-ray emission. This connection suggests that gamma-ray emission in globular clusters could also arise from unresolved X-ray sources or a relativistic electron population, perhaps generated by the millisecond pulsars. X-ray observations of further gamma-ray bright globular clusters would allow a functional relationship to be determined between diffuse X-ray and gamma-ray emission., 17 pages, 18 figures, accepted for publication in MNRAS

Kir7.1 is an inwardly rectifying potassium channel with important roles in the regulation of the membrane potential in retinal pigment epithelium, uterine smooth muscle, and hypothalamic neurons. Regulation of G protein–coupled inwardly rectifying potassium (GIRK) channels by G protein–coupled receptors (GPCRs) via the G protein βγ subunits has been well characterized. However, how Kir channels are regulated is incompletely understood. We report here that Kir7.1 is also regulated by GPCRs, but through a different mechanism. Using Western blotting analysis, we observed that multiple GPCRs tested caused a striking reduction in the complex glycosylation of Kir7.1. Further, GPCR-mediated reduction of Kir7.1 glycosylation in HEK293T cells did not alter its expression at the cell surface but decreased channel activity. Of note, mutagenesis of the sole Kir7.1 glycosylation site reduced conductance and open probability, as indicated by single-channel recording. Additionally, we report that the L241P mutation of Kir7.1 associated with Lebers congenital amaurosis (LCA), an inherited retinal degenerative disease, has significantly reduced complex glycosylation. Collectively, these results suggest that Kir7.1 channel glycosylation is essential for function, and this activity within cells is suppressed by most GPCRs. The melanocortin-4 receptor (MC4R), a GPCR previously reported to induce ligand-regulated activity of this channel, is the only GPCR tested that does not have this effect on Kir7.1.

47 Tuc was the first globular cluster observed to be $\gamma$-ray bright, with the $\gamma$-rays being attributed to a population of unresolved millisecond pulsars (MSPs). Recent kinematic data, combined with detailed simulations, appears to be consistent with the presence of an intermediate mass black hole (IMBH) at the centre of 47 Tuc. Building upon this, we analyse 9 years of \textit{Fermi}-LAT observations to study the spectral properties of 47 Tuc with unprecedented accuracy and sensitivity. This 9-year $\gamma$-ray spectrum shows that 47 Tuc's $\gamma$-ray flux cannot be explained by MSPs alone, due to a systematic discrepancy between the predicted and observed flux. Rather, we find a significant preference (TS $=40$) for describing 47 Tuc's spectrum with a two source population model, consisting of an ensemble of MSPs and annihilating dark matter (DM) with an enhanced density around the IMBH, when compared to an MSP-only explanation. The best-fit DM mass of 34 GeV is essentially the same as the best-fit DM explanation for the Galactic centre "excess" when assuming DM annihilation into $b\bar{b}$ quarks. Our work constitutes the first possible evidence of dark matter within a globular cluster., Comment: Accepted to be published as a Rapid Communication in Physical Review D. 6 pages, 2 figures

The city of Melbourne is located in a highly productive agricultural region with the capacity to meet approximately 41% of the city population’s food needs. Melbourne’s “foodbowl” is an important building block in a resilient and sustainable food system for this rapidly growing city. This article presents some findings of the Foodprint Melbourne initiative led by University of Melbourne researchers who worked in partnership with local governments to investigate the significance of periurban food production to the city’s long-term food security and the regional economy. They identified risks to city fringe food production from urban sprawl and the impacts of water scarcity, and generated an important evidence base to support the development of a vision and roadmap to strengthen the resilience of Melbourne’s foodbowl.

There are many advocates and critics of urban agriculture’s role in a sustainable food system but little quantitative data, potentially due the difficulties in collecting it. Urban food production is an example of a distributed system intrinsically linked to urban farmers and urban lifestyles and therefore cannot be recreated in a lab. Citizen science (CS) is identified as a potential method to measure aspects of urban agriculture but has potential issues associated with maintaining participation in data collection. This paper presents the development of a citizen science methodology combining general CS project design methods with methods for engaging and retaining participants in CS projects, based on motivation, for the design of a citizen science project measuring the sustainability performance of urban food gardens in Melbourne, Australia. It was found that an additional motivation emerged that is not yet documented in existing literature and is particular to citizen science projects. Other conclusions were also drawn related to timeline management, potential cost reductions conflicting with reducing barriers to participation and diversifying recruitment methods to attract participants with more time to be involved.

We analyse 30 Galactic globular clusters ( GC ) located off the Galactic plane, using 8 years of Pass 8 Fermi-LAT data in the range 60 MeV - 300 GeV with the analysis down to lower energy being performed for the first time. We refine the prior detections of 5 GC, 47 Tuc, NGC 6093, NGC 6218, NGC 6752 and NGC 7078. We also detect NGC 6254 for the first time. NGC 6093 and NGC 6218 exhibit flat hard spectra in the range 1 - 10 GeV. The lack of a spectral cut-off between 1-4 GeV in NGC 6093 and NGC 6218, suggests other sources of gamma ray emission apart from millisecond pulsars may be important in these GCs.

With the increasing concern given to pollution and climate change bio-based building materials have been pushed to the forefront of research in an effort to reduce the large carbon footprint of the construction industry in order to meet emission targets One of these materials is hemp concrete which is a bio-composite made up of the non-fibrous part of hemp called shiv, water and a lime binder. This study investigated two different binders; hydrated lime as a control and a composite binder containing 80% hydrated lime and 20% metakaolin. The effect of metakaolin is investigated on the mechanical, thermal and transport properties. The pre-treatment of the aggregate with linseed oil is also studied. It was found that the addition of metakaolin increased the compressive strength of the hydrated lime samples. It was also observed that for both binder types the addition of metakaolin into the binder increased the capillarity water absorption of the samples. The addition of metakaolin reduced the thermal conductivity of hydrated lime samples when the test was done in the direction perpendicular to the fibre orientation. Finally, the pretreatment of the aggregate with linseed oil increased the compressive strength and modulus of elasticity of the samples and greatly reduced the material’s capillarity absorption. Linseed oil pretreatment also lead to an increase in thermal conductivity of the samples., Academic Journal of Civil Engineering, Vol 35 No 2 (2017): Special Issue - ICBBM 2017

In recent decades sustainability, carbon footprint and pollution have become significant issues on a global scale. It is widely recognised that the carbon footprint of the construction industry is something that can be reduced and this has led to sustainable materials being used more and more widely to meet emissions targets. Two of these materials are hemp concrete and rapeseed-straw concrete which are bio-composites made of the bio-aggregate, water and a lime binder; in this investigation Vicat prompt natural cement (PNC). The addition of a viscosity modifying agent (VMA) is studied for its effect on the mechanical and transport properties. It was found that the use of a VMA was very effective at countering the two biggest weaknesses of bioaggregates as it reduced the capillarity absorption of the concrete significantly and also greatly increased the compressive strength and modulus of elasticity of the material., Academic Journal of Civil Engineering, Vol 35 No 2 (2017): Special Issue - ICBBM 2017

Food systems in cities are under increasing pressure. Food production is occurring further and further from the point of consumption and extreme weather events due to climate change are impacting on food supply networks. It is possible that cities will have to rely on their local regions to meet at least some of their food needs in the future. Although large amounts of food are produced on the outskirts of cities, it is not clear the extent to which the nutritional needs of inhabitants could be met sustainably. This paper aims to investigate if it is possible to feed the city of Melbourne a healthy diet from the local area (i.e. achieve direct food availability) and what that diet might look like. It tests a new methodology using linear programming to find the optimal mix of food types to produce a diet profile that meets the Australian Dietary Guidelines within theproduction capacity of the local ‘region’. Results from three region scenarios are presented – Greater Melbourne, Foodbowl and Rest of Victoria. No solution could be found that satisfied all constraints for any region, however this identified issues surrounding availability of certain food types, particularly fruit, vegetables and legumes. Systematically increasing certain constraints provided insight into how diets could be composed to meet requirements and where it might be necessary to increase production within a region or future proof food supply networks. It also highlighted conflicts between sourcing food locally and reducing carbon emissions.

This letter describes the further exploration of two series of M(1) allosteric agonists, TBPB and VU0357017, previously reported from our lab. Within the TPBP scaffold, either electronic or steric perturbations to the central piperidine ring led to a loss of selective M(1) allosteric agonism and afforded pan-mAChR antagonism, which was demonstrated to be mediated via the orthosteric site. Additional SAR around a related M(1) allosteric agonist family (VU0357017) identified similar, subtle 'molecular switches' that modulated modes of pharmacology from allosteric agonism to pan-mAChR orthosteric antagonism. Therefore, all of these ligands are best classified as bi-topic ligands that possess high affinity binding at an allosteric site to engender selective M(1) activation, but all bind, at higher concentrations, to the orthosteric ACh site, leading to non-selective orthosteric site binding and mAChR antagonism.

Information security and authentication are important challenges facing society. Recent attacks by hackers on the databases of large commercial and financial companies have demonstrated that more research and development of advanced approaches are necessary to deny unauthorized access to critical data. Free space optical technology has been investigated by many researchers in information security, encryption, and authentication. The main motivation for using optics and photonics for information security is that optical waveforms possess many complex degrees of freedom such as amplitude, phase, polarization, large bandwidth, nonlinear transformations, quantum properties of photons, and multiplexing that can be combined in many ways to make information encryption more secure and more difficult to attack. This roadmap article presents an overview of the potential, recent advances, and challenges of optical security and encryption using free space optics. The roadmap on optical security is comprised of six categories that together include 16 short sections written by authors who have made relevant contributions in this field. The first category of this roadmap describes novel encryption approaches, including secure optical sensing which summarizes double random phase encryption applications and flaws [Yamaguchi], the digital holographic encryption in free space optical technique which describes encryption using multidimensional digital holography [Nomura], simultaneous encryption of multiple signals [Pérez-Cabré], asymmetric methods based on information truncation [Nishchal], and dynamic encryption of video sequences [Torroba]. Asymmetric and one-way cryptosystems are analyzed by Peng. The second category is on compression for encryption. In their respective contributions, Alfalou and Stern propose similar goals involving compressed data and compressive sensing encryption. The very important area of cryptanalysis is the topic of the third category with two sections: Sheridan reviews phase retrieval algorithms to perform different attacks, whereas Situ discusses nonlinear optical encryption techniques and the development of a rigorous optical information security theory. The fourth category with two contributions reports how encryption could be implemented at the nano- or micro-scale. Naruse discusses the use of nanostructures in security applications and Carnicer proposes encoding information in a tightly focused beam. In the fifth category, encryption based on ghost imaging using single-pixel detectors is also considered. In particular, the authors [Chen, Tajahuerce] emphasize the need for more specialized hardware and image processing algorithms. Finally, in the sixth category, Mosk and Javidi analyze in their corresponding papers how quantum imaging can benefit optical encryption systems. Sources that use few photons make encryption systems much more difficult to attack, providing a secure method for authentication., Centro de Investigaciones Ópticas, Consejo Nacional de Investigaciones Científicas y Técnicas

Herein we report the discovery and SAR of a novel metabotropic glutamate receptor 3 (mGlu(3)) NAM probe (ML289) with 15-fold selectivity versus mGlu(2). The mGlu(3) NAM was discovered via a 'molecular switch' from a closely related, potent mGlu(5) positive allosteric modulator (PAM), VU0092273. This NAM (VU0463597, ML289) displays an IC(50) value of 0.66 μM and is inactive against mGlu(5).

Melbourne is surrounded by a highly productive foodbowl that currently grows a wide variety of fresh foods, but it faces challenges. • Melbourne’s foodbowl grows 47% of the vegetables produced in Victoria and has the capacity to meet around 41% of Melbourne’s total food needs. • As Melbourne grows to a population of 7-8 million people by 2050, it will need at least 60% more food. • If the city’s footprint continues to grow as it has in the past, the capacity of Melbourne’s foodbowl to meet the city’s food needs could fall to around 18% by 2050, due to population growth and urban sprawl. • Loss of production in the foodbowl is likely to contribute to higher food prices. • Melbourne’s foodbowl contributes $2.45 billion per annum to Melbourne’s regional economy and 21,000 full time equivalent jobs. • Melbourne’s food supply faces future challenges from the impacts of climate change, including water scarcity and extreme weather events. • Other major Australian state capitals also have productive foodbowls that contribute to fresh food supplies, but they are all under similar pressure from population growth and urban expansion. They are unlikely to be able to meet future deficits in Melbourne’s food needs. Melbourne’s foodbowl is an important building block in a resilient and sustainable food future for the city. • Ensuring a resilient food supply for Melbourne requires a precautionary planning approach that retains – or strengthens – the capacity of the city’s foodbowl. • The loss of Melbourne’s foodbowl is not inevitable as the city grows. If growth on the city fringe can be limited to existing growth corridors and strong targets are set for urban infill and increased urban density, the impact on the city’s foodbowl can be reduced. • Melbourne can plan for a resilient city foodbowl that provides healthy food for a growing population, promotes a vibrant regional food economy and acts as a buffer against future food system shocks. • Increased investment in delivery of recycled water from water treatment plants could create ‘drought-proof’ areas of food production. • A ‘joined up’ policy framework is required to plan for a resilient city foodbowl. Policy is needed to protect farmland, increase water access, reduce and reuse food waste, strengthen the regional food economy and attract farmers to farm in the city’s foodbowl.

This report explores Melbourne’s ‘foodprint’ – the environmental footprint of feeding the city. It takes a lot of land, water and energy to feed a rapidly growing city like Melbourne, and a significant amount of food waste and GHG emissions are generated as a result. As supplies of the natural resources underpinning food production become more constrained, the city will need to explore new approaches to increase the sustainability and resilience of its food supply. This report aims to provide an evidence base to support this process. The principal findings of this research are: • It takes over 475L of water per capita per day to feed Melbourne, around double the city’s household usage. • 16.3 million hectares of land is required to feed Melbourne each year, an area equivalent to 72% of the state of Victoria. • Feeding Melbourne generates over 907,537 tonnes of edible food waste, which represents a waste of 3.6 million hectares of land and 180 GL of water. • Around 4.1 million tonnes of GHG emissions are emitted in producing the city’s food, and a further 2.5 million tonnes from food waste. • Melbourne is likely to grow rapidly between now and 2050, and its foodprint will increase significantly as a result. • Melbourne’s city foodbowl could play an important role in increasing the resilience and sustainability of the city’s food supply. • The city foodbowl has significant capacity for production of fresh foods. It also has access to recycled water and organic waste streams, and could reduce the city’s dependence on distant sources of fresh foods. • Key vulnerabilities in Melbourne’s regional food supply include loss of agricultural land, water scarcity and the impacts of climate change. • Potential strategies to increase the sustainability and resilience of Melbourne’s regional food supply include increasing urban density, shifting to regenerative agriculture, increasing the use of recycled water for agriculture, reducing food waste and modifying our diets. • Multiple strategies are likely to be needed to increase the sustainability and resilience of Melbourne’s regional food supply. • Around 10% of the available recycled water from Melbourne’s water treatment plants would be enough to grow half of the vegetables that Melbourne eats. • Increasing urban density as Melbourne grows could reduce urban sprawl by about 50% over the next 20 years, saving 180,000 hectares of land in Melbourne’s foodbowl – an area equivalent to almost 5 times Victoria’s vegetable growing land.

There is wide variability in the methods of follow up of patients with colorectal cancer. For the majority of patients follow up comprises regular clinical assessment and measurement of carcinoembryonic antigen (CEA) with interval colonoscopy. Regular CT examinations will additionally detect distant disease such as liver and pulmonary metastases as well as local recurrence. With this in mind we highlight the importance of detecting recurrent colorectal cancer using both CT and MRI. Particular attention is given to the detection of surgically resectable disease as there is now increasing evidence that improvements in survival are achieved by aggressive surgical removal of such recurrences. We also use CT and MRI to illustrate the importance of pelvic relapse as a common clinical endpoint in rectal cancer and discuss the role of [18F]2-fluoro-2-deoxyglucose (FDG)-positron emission tomography (PET) in this subgroup of patients. We discuss the emerging role of endorectal ultrasound (ERUS)-directed biopsy in detecting early recurrence of rectal cancer, particularly in those patients at higher risk of recurrence., Integrated positron emission tomography/computed tomography (PET/CT) with 18F-labelled fluoro-2-deoxy-D-glucose (FDG) is emerging as a powerful technique for the assessment of patients with thoracic oesophageal and oesophago-gastric junction carcinomas. FDG PET/CT in staging cancers may identify primary tumours along with locoregional nodes and detect distant metastases. Using serial studies the response to neo-adjuvant treatment may be monitored. FDG PET/CT may detect recurrent disease. The limitations of FDG PET/CT include pitfalls such as physiological oesophagogastric junction FDG uptake and non-neoplastic inflammatory/infectious causes of FDG accumulation in the oesophagus and at the oesophago-gastric junction. Integrated FDG PET/CT may have a role in the detection of severe dysplasia associated with Barrett’s oesophagus. The standardized uptake value (SUV) can be used to aid determination of the significance of areas FDG uptake and provides a method of quantification in serial studies. Other investigations remain integral in the assessment of patients with thoracic oesophageal and oesophago-gastric junction carcinomas. Endoscopy and biopsy of suspicious areas is the cornerstone for establishing the diagnosis of upper gastro-intestinal tract malignancies. Small volume primary disease is not reliably detected on FDG PET/CT. In staging disease, endoscopic ultrasound remains the method of choice for assessing the primary site and adjacent para-oesophageal nodes. The most comprehensive non-invasive tool for detecting distant metastases is integrated PET/CT; its utilization can lead to more appropriate selection of patients for surgical resection. In this pictorial review we aim to use illustrative cases to summarize the role of FDG PET/CT in assessing patients with thoracic oesophageal and oesophago-gastric junction carcinomas., The aim of surgery in rectal cancer is to achieve a disease free circumferential resection margin (CRM). In our institution, MRI is used to stage rectal cancers pre-operatively. The aim is to identify those patients at risk of having an involved CRM at the time of surgery. Those who have no disease encroaching on the CRM proceed directly to surgery. Those with locally advanced cancers receive chemoradiation prior to surgery. They are subsequently re-staged with MRI. The aim of this study is to compare the accuracy of MRI for CRM prediction in these two groups of patients. Sixty-three patients with rectal cancer were studied retrospectively. Thirty-three patients proceeded directly to surgery. In 31 (94%) of these, MRI correctly predicted CRM status. Thirty patients underwent chemoradiation and repeat MRI prior to surgery. MRI correctly predicted CRM status in 21 (70%). In nine cases MRI predicted an involved CRM which was clear at resection (positive predictive value 47%). No patients were predicted to have a clear CRM by MRI which turned out to be involved at resection (negative predictive value 100%). Six patients were felt to have increased or unchanged tumour bulk. In these cases there was 100% agreement between MRI and pathology. MRI correlates well with pathology in patients who have not received chemoradiation. However, accuracy of MRI for prediction of CRM status is significantly reduced after chemoradiation. MRI tends to over stage CRM involvement in this situation., Aim Comparison of the localisation of enhancement areas and areas of highest metabolites ratio; correlation of the results with histopathologic examination. Materials and methods Twenty-one patients with prostate adenocarcinoma examined with magnetic resonance imaging (MRI) before prostatectomy. The MRI protocol was: TSE-xL/90 ax, sag, SE T1, whole pelvis ax, FSE-xL/90 ax, sag, MRS 3D with endorectal coil, multiphase enhanced fast GRE 3D; contrast dose, 0.2 ml /kgcc; speed, 2 ml /s; delay, 20 s. The colour map of the maximum slope of increase (MSI) and the time intensity curves in the region of the highest MSI in multiphase enhanced fast GRE sequence were compared with the areas of highest metabolites ratio Ch +Cr/Ci (CC/Ci) in MRS and correlated with the histopathologic result. Results The contrast enhancement of highest CC/Ci areas was detected in 17 (81%) patients, lack of enhancement in 4 (19%) patients. In 2 (10%) cases there was no correlation between MSI and CC/Ci, while the MSI result correlated more strongly with the histopathology. Overall, the MSI result corresponded to the histopathology in 19 (90%) cases. In the MSI region the enhancement was visible earliest and was the most intense in comparison to the enhancement in the benign prostatic hyperplasia foci. Conclusions The multiphase enhanced fast GRE sequence can improve the assessment of cancer foci localisation in MRS in patients with prostate adenocarcinoma., Purpose/methods Treatment of metastasis from non-seminomatous germ cell tumours of the testes is by chemotherapy and response is monitored by serum tumour marker levels and computer tomography (CT) scans. Growth of a lesion despite normal levels of serum tumour markers represents the growing teratoma syndrome. We present the retrospective imaging of seven patients, the largest series to date with growing teratoma syndrome. Results All patients had retroperitoneal spread. Two patients had mediastinal and pulmonary parenchymal disease. The masses were either solid, cystic or mixed. Two cystic masses, one retroperitoneal and one mediastinal, had thick enhancing walls, the other masses had thin walls. Five patients showed compression and displacement of the inferior vena cava, one had obstruction of the left ureter and one had compression and displacement of the bowel and psoas muscle. In the chest, compression of the left brachial plexus and of branches of the right pulmonary artery was seen. All patients underwent surgical removal of their masses. There was one intraoperative death; all other patients are currently disease free. Conclusion Growth of residual masses following surveillance scans of patients treated for non-seminomatous germ cell tumours with normal serum tumour markers should make the radiologist raise the diagnosis of the growing teratoma syndrome. Following diagnosis these tumours need to be treated by complete surgical resection to prevent encroachment on vital structures and prevent the possibility of dedifferentiation into a more aggressive tumour., Aim To describe the spectrum of MRI appearances of adenocarcinomas of the cervix. To correlate magnetic resonance imaging (MRI) and histopathological features. To emphasise the pitfalls and difficulties in staging adenocarcinomas and suggested improvements in MRI techniques. Content organisation MRI of 45 patients with histologically confirmed adenocarcinoma of the cervix was retrospectively reviewed. Thirty-six patients had radical hysterectomy and correlation of MRI and surgical specimen was performed. Nine patients had disease stage IIB or higher with follow-up MRI. For each tumour, site, size, proximal extension, parametrial invasion and nodal metastases on MRI and pathology were documented and compared. Common appearances and errors in MR staging and pitfalls are demonstrated. Conclusions Cervical adenocarcinomas are infiltrative tumours that commonly present with atypical MRI features of cervical cancer. Their patterns of disease, particularly endometrial and parametrial extension and early nodal metastatic involvement are particular pitfalls and these will be demonstrated with surgical correlation., Carcinoma of the cervix is the third commonest gynaecological malignancy worldwide. In the United Kingdom 3000 women are diagnosed with cervical cancer each year. Squamous and adenocarcinoma are the commonest pathological subtypes and constitute more than 95% of cervical carcinomas. Unusual cervical neoplasms, although rare, constitute an important subtype. These subtypes include adenoma malignum, glassy cell carcinoma, carcinoid/small cell carcinoma, melanoma, metastasis, lymphoma, rhabdomyosarcoma and mixed Mullerian sarcoma. Although histological confirmation is always required, some of these neoplasms have characteristic imaging features that may suggest the diagnosis. A pictorial review of the magnetic resonance appearance along with histological correlation will be performed. A detailed discussion of the various unusual histological subtypes will be undertaken., 18F-Labelled fluoro-2-deoxy-D-glucose positron emission tomography (FDG PET) and integrated FDG PET/computed tomography (FDG PET/CT) have many established roles in the management of a number of malignancies. There are few large studies regarding the use of FDG PET in gynaecological malignancy, but the relatively recent development of integrated PET/CT is resulting in its increased use in assessing cases of ovarian carcinoma. Combined scanners can help localise pathological activity and differentiate it from physiological radiotracer uptake. FDG PET/CT has little role in the evaluation of primary ovarian masses; ovarian uptake maybe seen in a wide range of benign conditions as well as malignancy. In assessing volume of disease in patients being considered for surgery FDG PET/CT may aid decisions about extent of debulking. FDG PET/CT can monitor response to treatment in patients undergoing chemo radiotherapy; distribution of uptake and the standardised uptake value (SUV) can be assessed on serial studies. In cases of suspected recurrence with plateaued or rising serum CA-125 levels and normal or equivocal conventional cross-sectional imaging FDG PET/CT may identify foci of disease. False negative studies can occur in diffuse peritoneal carcinomatosis; sensitivity is lowest in the pelvis. FDG PET/CT is more sensitive for lymph node metastases than peritoneal metastases. Using illustrative cases we aim to discuss the evolving potential uses of combined FDG PET/CT in the management of ovarian cancer., Aim The purpose of our study was to compare the effectiveness of 3.2, 5 and 7.5 mm slice thicknesses in the detection and characterisation of liver lesions found on computed tomography (CT) in patients with known or suspected malignant disease. Methods One-hundred and ten patients underwent portal phase imaging using four-slice multidetector CT (MDCT). Two blinded observers independently read hard copy images at each slice thickness. The size and location of each lesion detected was recorded by each observer on a diagram of liver segmental anatomy. Each lesion was characterised as benign, malignant or indeterminate in nature. A diagnostic confidence score was allocated for each lesion on a scale of 1–4. The pathology or behaviour of lesions was assessed using surgery with intra-operative ultrasound and histology, or interval imaging with magnetic resonance imaging, CT, or sonography. Results Two-hundred and ninety-four lesions were detected, 64 (22%) of which were malignant. Both observers detected significantly more lesions on the 3.2 mm vs. 7.5 mm slice thickness (p, Aim Hepatocellular carcinoma is the commonest primary hepatic malignancy worldwide, with a poor prognosis if untreated. Treatment modalities include: surgical, local ablation, systemic chemotherapy and immunotherapy, with long-term survival best in those patients undergoing liver transplantation. Radiofrequency ablation (RFA) is a commonly used local therapy that we have begun to incorporate into the treatment algorithm for HCC in our institution. This study examines the role of percutaneous RFA at a supraregional hepatobiliary and liver transplant centre. Method We report a single centre, retrospective review of patients with HCC who underwent percutaneous RFA between August 2003 and December 2005. Patients were identified from an HCC database and their imaging and medical records were examined. Data regarding demographics, liver disease diagnosis, tumour size and number, treatment episodes, complications, survival and other therapies were evaluated. RFA procedures and subsequent imaging review was carried out by three experienced hepatobiliary radiologists. Results Over the study period 27 patients received 30 treatment episodes of RFA for HCC (19 male; 8 female). The average patient age was 67 years (SD ± 11). The average lesion size was 2.6 cm (SD ± 1.6) with only one major complication (intra-peritoneal bleeding). At 6 weeks there was a good response to treatment in 47% of patients. Conclusion RFA is a safe and effective treatment in selected patients with HCC. Long-term follow up is required to determine the duration of treatment response and its impact on quality of life and survival., The role of iodine-123 labelled meta-iodo-benzyl-guanidine (MIBG) scanning in the evaluation of tumours of neural crest origin is well established. MIBG scanning is particularly useful in localising, staging and follow-up of tumours arising from the sympathetic nervous system, including phaeochromocytoma, paraganglioma and neuroblastoma. Less well recognised are its merits in the management of other neuro-endocrine tumours such as carcinoid tumours and medullary carcinoma of thyroid. Furthermore, MIBG scanning can identify patients suitable for radiolabelled MIBG therapy. In our institution, which is an oncology tertiary referral centre, approximately 25 MIBG scans are performed per annum. In this pictorial review, a number of clinical cases will be discussed, illustrating a range of pathological MIBG studies, with correlative cross-sectional imaging, biochemical and clinical data., The role of iodine-123 labelled meta-iodo-benzyl-guanidine (MIBG) scanning is well established in the localisation, staging and follow-up of neuro-endocrine tumours especially those arising from the sympathetic nervous system, such as phaeochromocytomas and paragangliomas. Despite the merits of MIBG scanning, diagnostic problems are frequently encountered for a range of reasons including, artefacts, poor lesion/background activity ratio, non-specific activity and renal excretion. Optimisation of the imaging protocol and techniques to overcome these problems will be discussed with particular reference to: patient preparation; multiple time points of image acquisition; use of single photon emission computed tomography (SPECT); co-administration of MAG3 to differentiate renal and adrenal activity; image processing, e.g. subtraction of noise from high energy photons. Clinical examples from our institution, which is an oncology tertiary referral centre, performing approximately 25 MIBG scans per year, will be shown to illustrate normal MIBG biodistribution and diagnostic pitfalls., Aim To demonstrate the range of appearances of islet cell tumours of the pancreas (ICP) on computed tomography (CT), magnetic resonance imaging (MRI) and octreotide imaging. To assess the performance of each imaging modality and correlate imaging findings with clinical, biochemical and histopathological results. Content organization Imaging of 50 patients with 56 tumours (sporadic and syndrome associated, benign and malignant) was retrospectively reviewed. Number of tumours, size, site, metastatic disease, CT enhancement, MRI signal characteristics and octreotide positivity was documented. Clinical presentation, biochemical data (serum insulin, somatostatin, glucagon, gastrin and urine 5HIAA) was correlated for each patient. Sensitivity, specificity and accuracy of each modality for tumour detection were calculated. Conclusion/summary Our study is the largest cohort of islet cell tumours studied to date and will be the first to correlate the range of clinical and imaging patterns in ICP. We propose an imaging algorithm based on biochemical and clinical manifestations., Gadolinium-diethylenetriamine penta-acetic acid (Gd-DTPA)-enhanced magnetic resonance imaging (MRI) has developed from an aid to morphological imaging of cancer to functional dynamic T 1 weighted or T 2* weighted dynamic scanning. Additionally, blood oxygenation level dependent (BOLD) and diffusion-weighted imaging (DWI) can be performed, all of which can yield parametric images that reflect different aspects of the tumour microenvironment. All can be performed in a one hour-long scanning session which is short enough to be acceptable to patients. BOLD imaging uses a sequence sensitive to small paramagnetic changes, e.g. GRE/FLASH (TE 5–60 ms, TR 105 ms, α=40^, 8 mm slices), or echo planar imaging (EPI). Diffusion uses single or multi-shot EPI sequences, minimising the echo time and using multiple b values. Our two-point method for acquiring quantitative images (Ktrans, kep, ve) from T 1 weighted dynamic scanning involves a proton density weighted sequence (TE 4.7 ms, TR 350 ms, α=35^, 3×8 mm slices) being performed before 40 T 1 weighted scans (typically 3×8 mm slices: TE 4.7 ms, TR 11 ms, α=35^). A T 2* weighted sequence, e.g. GRE/FLASH (TE 20 ms, TR 30 ms, α=40^) with time resolution, Aim To determine the patterns of disease in patients with inoperable or recurrent retroperitoneal liposarcoma. Methods Twenty-one consecutive patients with retroperitoneal liposarcoma were identified from clinical and radiological databases at our tertiary oncology centre. Computed tomography (CT) imaging was retrospectively reviewed for all cases. Results There were 12 (57.1%) males. The median age at first imaging was 53.8 (27.7–76.9) years. Sixteen (76.2%) patients had undergone previous surgery; in 10 of these patients (62.5%) resection was described as complete. CT examinations from all 21 patients were reviewed. Of the 16 patients previously treated with surgery, 13 (81.3%) were found to have residual or recurrent tumour on CT. In eight patients (61.5%), tumour was present in the retroperitoneum alone and in five patients (38.5%) tumour was seen in both the retroperitoneum and abdominal cavity. Retroperitoneal recurrences were of mixed fat and soft tissue density. Larger retroperitoneal recurrences displaced adjacent structures and occasionally protruded into the peritoneal cavity. Early recurrence of tumour was seen as a subtle local increase in fat or as small soft tissue nodules. These were often overlooked on initial reporting. Five patients (23.8%) were referred with inoperable disease and no previous surgery. Four of these patients were treated with chemotherapy but all progressed. Conclusion Most tumours were large with marked mass effect. Early recurrence may be subtle with increase in fat volume or new nodules and can be easily overlooked. Early diagnosis of recurrence on CT may allow salvage surgery., Magnetic resonance imaging (MRI) is the best imaging study for the evaluation of muskuloskeletal soft tissue neoplasm. MRI is used both for tissue characterization and local staging of soft tissue sarcomas. The multiplanar imaging capacity and soft tissue differentiation provided by MRI makes it ideal for the evaluation of these lesions. This poster reviews the imaging characteristics of many histologic subtypes of soft tissue sarcoma including malignant fibrous histiocytoma, liposarcoma, malignant peripheral nerve sheath tumors, and synovail cell sarcoma. Other rare soft tissue malignancies are also discussed. The important factors in soft tissue tumor staging are also reviewed. The radiologist must evaluate each lesion for neurovascular involvement, articular extension, osseous invasion, and regional metastasis. Benign lesions tend to be small, superficial and homogenous while malignant lesions tend to be large, deep and heterogeneous. There is, however, a broad spectrum of overlap in the imaging features of benign and malignant soft tissue tumors. Although in most cases MRI can confidently differentiate benign from malignant neoplasm, MRI not infrequently is able to definitively characterize some lesions. Benign lesions with a characteristic imaging appearance (lipoma, hemangioma, shwannoma, fibromatosis, giant cell tumor of tendon sheath, pigmented villonodular synovitis) are reviewed., Purpose/introduction To give an accurate presentation of ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI) findings in soft tissue liposarcoma of the extremity, with pathologic correlations after surgery. Materials and methods Liposarcoma is the second most common type of soft tissue sarcoma (10%–35%). Its histologic subtypes are categorized as: well differentiated, dedifferentiated, myxoid, pleomorphic and mixed type. Patients were evaluated with US, CT and MRI. Results The lesions are identified with relative ease on CT and MRI, due to the typical density/signal of the fatty areas of the liposarcoma. In these cases, the non-fat areas, on which to direct the biopsy, are picked up with imaging. Special attention should be focussed on the density/signal intensity in tumoral nodules and septae. Myxoid liposarcomas have some peculiarities such as intramuscular position, pseudocystic aspect with peripheral enhancement, small solid nodules, or septa containing fat. Discussion/conclusion Knowledge of the anatomo-pathological and anatomo-surgical substrate of lipomasacromatous tumors of the extremity soft tissues constitutes the basis for diagnostic imaging assessment and is fundamental for optimal patient management., Chondrosarcomas are malignant tumours of the musculoskeletal system which characteristically produce a cartilage matrix. These tumours arise spontaneously within the bones or soft tissues (primary chondrosarcoma) or from pre-existing enchondromas or osteochondromas. Primary bone chondrosarcoma is a relatively common neoplasm, accounting for up to 27% of all primary bone malignancies; there are however numerous subtypes which occur with varying frequency. Conventional intramedullary chondrosarcoma accounts for over 60% of these tumours while extraskeletal chondrosarcomas are responsible for only 2% of all soft tissue sarcomas. Other recognised subtypes of primary chondrosarcoma include juxtacortical, dedifferentiated, clear cell, mesenchymal and myxoid. The aim of our presentation is to illustrate varied radiological appearances of these tumours. The clinical notes and radiological findings of eight surgically proven cases of chondrosarcoma consisting of five skeletal and three extraskeletal tumours were reviewed. Seven cases of primary chondrosarcomas with a single case of sarcoma arising from an osteochondroma were identified. Plain film and computed tomography (CT) findings of enchondral ossification ranged from large bizarre and poorly demarcated mineralization expected in a malignant tumour to finer well defined calcification more commonly associated with benign chondroid lesions. Non-calcified tumours were also noted. Cross-sectional imaging demonstrated tumours with a lobular appearance associated with central low attenuation on CT and high signal on T2-weighted magnetic resonance (MR) sequences reflecting their high water content. The pattern of MR contrast enhancement was predominantly peripheral and septal in nature. Awareness of the spectrum of imaging findings in chondrosarcoma will allow for accurate diagnosis, staging and surgical planning for these malignant tumours., Our objective was to review the computed tomography (CT) appearances of bone lesions detected on positron emission tomography (PET)/CT images, and to assess our initial experience of how many PET detected bone lesions were visible on our CT images. It has previously been found that only half of metastatic bone lesions detected on PET imaging are visible on CT scanning, having implications for both accurate prognosis and for suitability for surgery. Our PET/CT images were independently reported by three consultant radiologists, all with dual accreditation in nuclear medicine. We retrospectively reviewed the CT images of bone lesions detected on PET scanning, and present a comprehensive pictorial review of 19 patients with a variety of imaging appearances of bone metastases., Introduction Between the anatomic structures the skeletal muscles are less frequently involved in metastatic lesions but the real incidence is difficult to determine because they are not always adequately investigated. Our objective is to describe computed tomography (CT) and magnetic resonance (MR) findings of metastasis of different origin involving various muscles of the skeleton. Materials and methods Thirteen patients with histologically proven muscular metastatic lesions (four from melanoma, three from colorectal carcinoma, three from lung cancer, two from breast cancer, one from urothelial cancer) were studied with helical CT (Tomoscan SR 700 Philips) after i.v. iodine contrast medium. Eight were studied with MRI (SE T1-W, T2-W and contrast enhanced T1-W) on a 1.5 T unit (Siemens). Results Muscles adjacent to the trunk such as paraspinal, iliopsoas, iliacs and gluteous are more commonly involved. In three cases metastatic involvement was observed in patients with clinically silent muscular disease and this evidence casts doubt on the real frequency of these hematogenous metastases. Conclusions CT and MR allowed good definition of muscular metastatic lesions. MR, better than CT, determines the anatomic location, the extension of lesions and it provides a better tissue characterization., The most common malignant soft tissue mass is a soft tissue sarcoma, but as a group, soft tissue sarcomas represent less than 1% of all malignancies. In contrast, lymphoma is over ten times more common a malignancy than soft tissue sarcoma, but lymphoma as a cause of a malignant soft tissue mass is rare, and primary soft tissue lymphoma accounts for only 0.11% of all malignant lymphomas. Differentiation between the two malignancies is of critical importance with respect to management and prognosis, soft tissue sarcomas being treated primarily by radical surgical excision and radiotherapy, often sacrificing a degree of function to achieve tumour clearance, whereas lymphomas are treated with chemoradiotherapy, often with a good outcome. Nearly all the previously reported cases of lymphomas presenting as soft tissue masses are in the pathology or surgical literature, and few reports define the clinical and radiological features of this condition. We describe a series of ten cases of lymphoma presenting as soft tissue masses to the sarcoma unit at our institution over a 2-year period. We illustrate key computed tomography and magnetic resonance imaging features such as regional lymph node involvement, the disruption of fascial planes and the infiltrative pattern of muscle involvement, with histopathological correlation, to distinguish the two conditions. We emphasise that even with advances in imaging technology the definitive diagnosis must be made by excision biopsy., Aim To audit the proportion of images available for radiological review prior to a Cancer Multidisciplinary Team Meeting (MDTM). The RCR guidelines published in ‘Cancer Multidisciplinary Team Meeting—Standards for Clinical Radiologists’ were used as the standard. These state that there should be prior review of all images by an individual with appropriate expertise and with sufficient time to provide an unhurried professional opinion for the MDTM. Methods Chest and haematology MDTMs were attended over a 4 month period and the number and types of cases on which an immediate opinion was requested were recorded. Results In total 316 patients were discussed. At only three meetings (out of 23) were all images available for prior review. Ninety seven patients’ images were brought to the MDTMs for an immediate opinion over the study period. Sixteen of these patients were new additions to the circulated MDTM list whilst the remaining 81 were patients with foreign films or local hard copy only examinations. Over two-thirds of the images on which an immediate opinion was requested were cross-sectional examinations where there were also frequently old images for comparison. The remaining modalities were plain films, ultrasound and nuclear medicine. An opinion was offered on all of these images. Conclusion Our results fell short of the recommended 100% of images that should be reviewed prior to a Cancer MDTM (at 69%) potentially to the detriment of patient care. The introduction of PACS should improve our ability to preview images as most problems arose due to unavailability of images., Radiology departments in many parts of Africa cannot afford to purchase expensive PACS systems. One of us (BAS) is a South African Radiologist currently working in the UK but involved in the African Organisation for Research and Training in Cancer (AORTIC) whose aim is to promote cancer awareness throughout Africa. BAS hopes to make a meaningful radiological contribution to AORTIC by organising the equivalent of UK cancer MDT meetings between different African countries and centres as well as involving the expertise of appropriate radiological colleagues worldwide. Consequently BAS has been involved with the other co-authors of this abstract in trialling ‘disect’—an inexpensive PC based 3-D DICOM viewing system (http://www.disectsystems.com). The results of these trials in a number of UK non-PACS hospitals have been presented elsewhere. Disect has powerful networking capabilities that allow users at two different locations, each running the disect software and with the same DICOM file installed, to review and interact with that particular case simultaneously, with connection provided by local area networks and/or the internet. We feel this has considerable potential for specialist centres throughout Africa, or indeed any other parts of the world that wish to link up and share expertise. The purpose of this abstract is to draw members of the ICIS’s attention to (a) the existence of AORTIC and (b) the future possibilities of joint radiological teaching and research projects with African nations., The effective management of patients with cancer requires a multidisciplinary team approach with the diagnostic radiologist playing an extremely important role. Through the arsenal of imaging modalities available, the radiologist detects and elucidates the significance of the findings in any investigation, be it for the purposes of screening, diagnosis, staging, treatment planning, evaluation of response to therapy and follow-up of each disease site in the cancer patient and supporting clinical trials of new therapeutic agents. The extent to which these several roles of medical imaging facilities are put to use in the management of cancer, in view of the paucity of imaging modalities in this environment has not been evaluated. This study was designed to evaluate the degree of awareness of medical practitioners of the several roles of medical imaging in the management of cancer in Lagos, Nigeria, and evaluate the extent to which medical imaging facilities are being effectively used in the management of cancer in Lagos, Nigeria. All the requests forms for cancer patients seen in the six busiest radiology departments in Lagos, during the period January 2003 to December 2003 were reviewed. The radiologic investigative modality requested, the indications for the investigation and the referring clinicians’ specialties were noted. The percentages of requests made for the various purposes listed above were evaluated. We concluded that medical imaging is grossly underutilized in the management of cancer in this environment, the largest requests for medical imaging being for diagnostic and staging purposes., Purpose To present the imaging findings of tumours of the globe and orbit accompanied by a description of the most appropriate imaging modality in aid of establishing a diagnosis. Background Radiological imaging of tumours of the globe and orbit provides valuable additional information to the clinical history and examination in diagnosing the type of tumour. There is a wide spectrum of tumours of the globe and orbit given their small confines. Currently, the commonest imaging modalities used are computed tomography (CT) and magnetic resonance imaging (MRI). CT is the most useful tool in the detection and localisation of these tumours. As it provides more information with regards to bony landmarks, it is vital in pre-operative planning. MRI, however, is superior in evaluating intracranial extension. Ultrasound may still be used as an adjunct in the evaluation of fluid filled tumours. Method The imaging findings of tumours of the globe and orbit are presented with an educational text and description of the most appropriate radiological imaging modality. Conclusion This pictorial review aims to familiarise the radiologists and clinicians with the imaging appearances of tumours of the globe and orbit accompanied by important features and suggestions that the clinicians could identify with in further management., Aim To show the value of imaging in the control of head and neck cancer patients treated with chemotherapy, chemoradiation and targeted biological therapy. Materials and methods Sixty-one head and neck tumour patients with stage III/IV, or recurrence (48 squamous cell carcinoma, 2 adenocarcinoma, 3 anaplastic carcinoma, 5 adenoid cystic carcinoma, 2 olphactorius neuroblastoma, 1 chondrosarcoma) were evaluated. The sites of origins were: 8 sinonasal, 10 epipharynx, 11 oropharynx, 14 oral cavity, 13 hypopharynx, 2 larynx, 3 salivary gland. Thirty-nine patients were examined with magnetic resonance imaging (MRI) (1.5 T), seven with computed tomography (CT) (single detector spiral CT or multidetector CT, 16 detector rows) and 15 with both modalities. Imaging was made prior to therapeutic decision, as well as for evaluation of therapy response. After treatment, a baseline scan (1–3 months after treatment) and in general 3 monthly follow up examinations were performed. Functional MR imaging with dynamic contrast enhancement evaluation and time-signal intensity curve analysis was also performed in 16 patients. Results The patients were treated with combined chemotherapy (27), radiochemotherapy (34) and targeted biological therapy was given for 14 patients in a combination of chemotherapy or chemoradiation. In the observed time period (May 2004 to May 2006) 17 complete responses, 32 partial responses, and 12 cases of progressive disease were evaluated. Conclusion Chemotherapy, chemoradiotherapy and targeted biological therapy are promising developments in the management of advanced head and neck cancer. After the introduction of ‘organ preservation’ protocols the role of imaging has become more important. The use of contrast enhancement as a marker of angiogenesis can improve diagnosis. Angiogenesis results in changes in the parameters of vascular physiology and thus alters the pattern of contrast enhancement., Positron emission tomography (PET)/computed tomography (CT) imaging is subject to a great number of artifacts due to the variety of physiological and non-physiological uptake in whole body scanning using glucose as a tracer. We have analyzed 300 consecutive PET/CTs (Philips, Gemini GXL, Syntegra Petview) which were performed to evaluate cancer patients according to approved indications. Following analysis of physiological uptake and their variations, we studied artifacts in terms of frequency and impact on PET/CT interpretation emphasising the risk of misinterpretation with erroneous or doubtful images. Physiological uptake (brain, myocardium, liver–spleen, digestive and urinary tracts) are constantly visualised, whereas their variations (salivary, pulmonary hiles, mediastinum, muscles, brown fat, joints, testis, uterine mucosa, nipples, vessels, thyroid, thymus, respiratory movements) are visible in 80% of cases. Artifacts (post-therapy modifications, injections, punctures, metallic implants, indwelling catheters, scars) were seen in 20% of cases creating false positive images which were subject to error or litigious interpretation in 5% of cases. A CT performed with diagnostic quality using iodinated contrast injection (Iomeprol, Bracco) and diluted digestive opacification (Telebrix, Guerbet), solved several misinterpretation problems. In our experience iodine did not create artifacts. Thus we conclude that PET/CT imaging is very frequently hampered by artifacts and that the CT part of this dual imaging should be performed with the best possible quality in order to alleviate most interpretation problems., Positron emission tomography (PET)-computed tomography (CT) is often perceived as the gold standard investigation for the diagnosis and staging of malignancy. Artefacts relating to poor patient preparation and scanning technique, normal physiological uptake, anatomical variants, and benign pathologic uptake can mimic disease and pose a diagnostic conundrum. We present examples of cases we have encountered in our practice, which illustrate these potential pitfalls, the recognition of which will improve the efficacy of PET-CT reporting., Aim The purpose of our study was to highlight some of the medicolegal issues encountered in a busy symptomatic breast care clinic. Methods We performed a retrospective review of all breast imaging and image guided histopathological specimens over a 2-year period (2003–2005). Results Correlation of histopathological reports and breast imaging studies can confirm a correct BIRADS classification in the majority of patients, however in a minority the receipt of a discordant specimen prompts the radiologist to repeat imaging and/or to re-biopsy. The multi-disciplinary meeting provides a forum for discussion of all breast biopsy specimens, and imaging findings with our clinical colleagues, ensuring that all three components of the ‘triple test approach’ are concordant and consistent. With relevant examples, in the form of case studies, we outline some of the medicolegal issues of import to the breast radiologist and emphasise some learning points we feel may reduce the risk for both patient and physician., Aim Metastatic breast cancer involves commonly liver, brain and skeletal systems. Metastatic involvement of the gastrointestinal and genito-urinary tract is less frequent, but is well documented, particularly with invasive lobular cancer. We demonstrate a spectrum of abdominal imaging findings in patients with metastatic breast cancer, in order to illustrate its diverse imaging findings. Materials and methods A search was performed of a hospital database of 748 breast cancer patients. Sixty patients with metastatic abdominal involvement were identified and the imaging files of these patients were reviewed. Results Imaging of the cohort of patients revealed metastatic disease in commonly recognised sites in the abdomen, including, liver, peritoneum and ovary. Less frequently encountered sites of abdominal breast metastases including rectum, large intestine, stoma and endometrium were also identified. Images of typical and less common sites of metastatic spread are illustrated and the findings are discussed. Conclusion Metastatic breast cancer can present with a myriad of abdominal visceral involvement. The illustrated cases emphasise the necessity to consider metastatic disease when patients with breast cancer present with abdominal symptoms or imaging findings., The demand for functional imaging in the staging and management of breast cancer is increasing. We aimed to identify the areas where positron emission tomography (PET)/computed tomography (CT) has been most beneficial in defining disease in patients with breast cancer at our unit, and the impact of these findings on the clinical management of these patients. Fifty consecutive patients with breast cancer referred to our department for a PET/CT examination between March 2004 and April 2006 were retrospectively assessed. PET/CT imaging findings were subsequently compared to follow up clinical, PET/CT and other imaging data to clarify disease sites. PET/CT confirmed the findings obtained on conventional imaging without demonstrating new findings in 32 patients. PET/CT demonstrated new areas of occult disease in 18 patients. Bone disease and locoregional adenopathy were the commonest sites. A true negative PET/CT examination occurred in 10 patients, and specific equivocal findings from other examinations were negative in 7 patients. Significant equivocal new PET/CT findings necessitating a further radiological examination, biopsy or clinical follow up to subsequently exclude disease were identified in 5 patients. Management changes made subsequent to the PET/CT examination findings occurred in 24 patients and included change from surgical management to systemic medical treatment and changes to the radiotherapy fields. In conclusion, PET/CT is an excellent modality at identifying/restaging (occult) metastatic disease in patients with breast cancer, especially at bony (lytic) and lymph node sites, with consequent patient management change., Aim Most currently published data regarding lung neoplasm doubling times (DTs) are based on gross measurements from conventional radiographs. The aim of our study was to determine and compare more precise DTs and growth rates (GRs) of lung lesions, based on volumetric measurements from thin section computed tomography (CT) imaging. Also, we aimed to determine if DTs differed significantly when compared by tissue diagnosis or measurement technique. Methods Institutional patient databases were searched to identify previously untreated patients with > two thin section CT scans showing a growing lung lesion, for which subsequent tissue diagnosis was obtained. Lesion volumes were derived using semi-automated computer techniques with either (1) direct volume measurement or volume calculation based on (2) lesion area or (3) lesion diameter. Volumes were calculated via methods (2) and (3) by modeling each nodule as a sphere, using the single axial CT image showing the largest area. Results Of 46 nodules evaluated, the diagnoses were: 8 benign, 7 metastatic, 3 lymphomas, and 28 primary lung malignancies (15 adenocarcinomas, 8 squamous carcinomas, and 5 miscellaneous). Mean DTs ranged from 49 to 146 days. There were no significant differences in GRs among the different histologies (p=0.43, F-test). There was considerable variability among GRs using different volume determination methods (R2=0.61–0.71, Pearson’s correlation). Conclusions Lesions of different histology showed great overlap in GRs. Different types of volume determination methods gave considerably different results; therefore GR comparisons should be made using similar volume measurement methods., Positron emission tomography (PET) is increasingly used in the evaluation of lung cancer patients. It is used to assess nodal involvement and distant metastases prior to surgery. It is also used in the investigation of solitary pulmonary nodules and other focal lung lesions. The recent guidelines published by the National Institute for Health and Clinical Excellence (NICE) state that all potential surgical patients should have a [18F]fluorodeoxy glucose (FDG) PET scan prior to surgery, and all patients planned for radical radiotherapy should also have a PET scan to assess whether there are any distant metastases. In this exhibit we would like to describe our experience in the evaluation of 50 patients with lung cancer where we analysed the PET scan reports and correlated with the CT scan findings and decided whether each was either upstaged, down staged or had no change from CT. We discuss the role of PET in the management of lung cancer patients and present illustrative cases., Aim Malignant pleural mesothelioma (MPM) is an increasingly prevalent tumour. It is expected to reach its peak incidence over the next 10–20 years. Our review will retrospectively describe the patterns of disease and assess the distribution of frequently associated features on computed tomography in 40 histologically confirmed MPM. Content organization For each tumour we document: (1) type of pleural thickening and classify it into thin, thick, diffuse or lobular; (2) we measure maximum thickness of MPM at presentation; (3) presence of pleural effusions recorded as small, moderate or large; (4) ipsilateral lung infiltration; (5) contralateral lung involvement; (6) frequency of plaques and calcification, indicative of previous asbestos exposure; (7) frequency of bone erosion; (8) frequency of extra-thoracic disease including liver, adrenals and other viscera. Conclusion/Summary We show the spectrum of disease in MPM and emphasise the patterns most frequently associated with MPM. Data are provided on the frequency of CT features, not previously performed.

Within the literature, theories and analyses of social involvement or participation have focussed primarily on the political and formal role of participation within the community or neighborhood. This study illustrates, through qualitative inquiry, that within small rural communities, individuals find it difficult to separate formal and informal participation, when both have an equally important role to play in community life. Fifty-five structured interviews were conducted with women across six rural shires in the southwest region of Western Australia. Qualitative analysis revealed that approximately 50% of women, when asked about their involvement in their community, referred initially to their informal participation within the community, rather than their participation in formal community groups or associations. These results are discussed in relation to life in small rural towns. © 2002 Wiley Periodicals, Inc.

International audience; This paper presents an analysis of the aeroelastic galloping of an elastically mounted square cross section in a free stream. The classic quasi-steady model [1] is used as a starting point. From this, the relevant time scales and dimensionless groups of the problem are derived. The time scale analysis shows that the mechanism of frequency selection by the oscillating system changes for heavy and light bodies. Results from direct numerical simulations are presented and compared against results from the simplified quasi-steady model, showing that the quasi-steady is quantitatively valid for heavy bodies, and at least generally qualitatively valid for light bodies. Results of experiments on light bodies also show this general qualitative agreement. However, there are also regimes of nonlinear interaction between the galloping and vortex shedding that the simplified model cannot capture.

This paper examines the concept of moral community within a rural context. The theory of moral community is discussed in relation to research in the social justice and community psychology literatures, and is related to participation in voluntary community organizations. A total of 388 women, located across six rural shires in the Great Southern Region of Western Australia, participated in the study. Results suggest that individuals participating within different community organizations or groups differ in their intensity of moral community feelings, and that sporting groups have much lower feelings of moral community than most other community organizations. The results of the study are then discussed in relation to the literature on group structure and climate. © 1996 John Wiley & Sons, Inc.

The Non-local Photo-Polymerization Driven Diffusion (NPDD) model was introduced to describe the observed drop-off in the material’s response for higher exposing spatial frequencies. Recent work carried out on the modeling of the mechanisms which occur in photopolymers during- and post-exposure, has led to the development of a tool, which can be used to predict the behaviour of these materials under a wide range of conditions. In this article, based on the chemical reactions of chain transfer agents, we explore this extended NPDD model, illustrating some of the useful trends, which the model predicts and we analyse their implications on the improvement of photopolymer material performance.

An understanding of the photochemical and photo-physical processes, which occur during photo-polymerization, is of extreme importance when attempting to improve a photopolymer material’s performance for a given application. Recent work carried out on the modeling of photopolymers during- and post-exposure, has led to the development of a tool, which can be used to predict the behavior of a number of photopolymers subject to a range of physical conditions. In this paper, we explore the most recent developments made to the Non-local Photo-polymerization Driven Diffusion model, and illustrate some of the useful trends, which the model predicts and then analyze their implications on photopolymer improvement.

In this chapter we briefly review some of the developments which have been made in the area of photopolymer material development for applications such as holography. We also examine some of the extensions which have been made to the theoretical models of the processes which occur during free radical photo-polymerisation, namely the Non-local Photo-polymerisation Driven Diffusion (NPDD) model. An understanding of these photochemical and photo-physical processes is of extreme importance when attempting to improve a photopolymer material’s performance for a given application. We will explore the most recent developments made and illustrate some of the useful trends, which this NPDD model predicts and then analyze their implications on photopolymer improvement. Among the effects examined are; the temporal and spatial primary radical generation (the driving force of photo-polymerisation), multiple termination mechanisms, non-local polymer chain growth, the effects of oxygen inhibition, mass transport effects (diffusion), dark reactions (post exposure effects) and chain transfer, to name a few.

The non-local photopolymerization driven diffusion (NPDD) model predicts that a reduction in the non-local response length within a photopolymer material will improve its high spatial frequency response. The introduction of a chain transfer agent reduces the average molecular weight of polymer chains formed during free radical polymerization. Therefore a chain transfer agent (CTA) provides a practical method to reduce the non-local response length. An extended NPDD model is presented, which includes the chain transfer reaction and most major photochemical processes. The addition of a chain transfer agent into an acrylamide/polyvinyl alcohol photopolymer material is simulated and the predictions of the model are examined. The predictions of the model are experimentally examined in part II of this paper.

The Non-local Photo-Polymerization Driven Diffusion (NPDD) model indicates how a material’s performance might be improved, and provides a tool for quantitive comparison of different material compositions and to predict their fundamental limits. In order to reduce the non-locality of polymer chain growth (i.e the non-local response parameter, σ) and to improve the spatial frequency response of a photopolymer material, we introduce the chain transfer agent (CTA). In the literature, extensive studies have been carried out on the improvements of the non-local response modifying by the CTA, sodium formate, in the polyvinyl alcohol-acrylamide (PVA/AA) material. In this article, i) based on the chemical reactions of CTA, we extended the CTA model in the literature; ii) we compare two different CTA materials, sodium formate and 1-mercapto-2-propanol without cross-linker in order to obtain the experimental confirmation of the reduction in the average polymer molecular weight is provided using a diffusion-based holographic technique; iii) we examine the non-local responses of several spatial frequencies with the two CTAs. Using the extended CTA model it is demonstrated that the CTA has the effect of decreasing the average length of the polyacrylamide (PA) chains formed, thus reducing the non-local response parameter, especially, in the high spatial frequency case.

Photosensitive polymers are of practical importance, and mass transport within such materials plays a critical role in their behavior. Building on the work in Part I [J. Opt. Soc. Am. B doc. ID 136413 (posted 5 January 2011, in press)], the diffusion constants of a number of materials (i.e., acrylamide, polyacrylamide, water, propanol, and acetone) within a photosensitive layer are measured. A combination of optical and physical chemistry techniques is applied under different conditions. Determining the rates of diffusion is beneficial as it: (i) indicates material stability over time and (ii) supports material characterization, modeling, and performance optimization.

For photopolymers, knowing the rate of diffusion of the active monomer is important when modeling the material evolution during recording in order to understand and optimize their performance. Unfortunately, a confusingly wide range of values have been reported in the literature. Re-examining these results, experiments are carried out for both coverplated (sealed) and uncoverplated material layers and the measurements are analyzed using appropriate models. In this way, a more detailed analysis of the diffraction processes taking place for large-period gratings is provided. These results, combined with those in Part II, provide unambiguous evidence that the monomer diffusion rate in a commonly used acrylamide polyvinyl alcohol-based material is of the order of 10−10 cm2=s. This value closely agrees with the predictions of the nonlocal polymerization-driven diffusion model.

The use of theoretical models to represent the photochemical effects present during the formation of spatially and temporally varying index structures in photopolymers, is critical in order to maximise a material’s potential. One such model is the Non-local Photo-Polymerization Driven Diffusion (NPDD) model. Upon application of appropriate physical constraints for a given photopolymer material, this model can accurately quantify all major photochemical processes. These include i) non-steady state kinetics, (ii) non-linearity iii) spatially non-local polymer chain growth, iv) time varying primary radical production, v) diffusion controlled effects, vi) multiple termination mechanisms, vii) inhibition, (viii) polymer diffusion and ix) post-exposure effects. In this paper, we examine a number of predictions made by the NPDD model. The model is then applied to an acrylamide/polyvinylalcohol based photopolymer under various recording conditions. The experimentally obtained results are then fit using the NPDD model and key material parameters describing the material’s performance are estimated. The ability to obtain such parameters facilitates material optimisation for a given application.

The development of suitable recording media for applications such as holographic optical elements and holographic data storage are of significant research and commercial interest. In this paper, a photopolymer material developed by Bayer MaterialScience is examined using various optical techniques and then characterised using the Non-local Photopolymerization Driven Diffusion model. This material demonstrates the capabilities of a new class of photopolymer offering high index modulation, full colour recording, high light sensitivity and environmental stability. One key result of this study is the material’s high spatial frequency resolution, indicating a very low non-local effect, thus qualifying it as a very good storage medium.

Nonverbal synchrony is an important element in human-human interaction. It can also play various roles in human-computer interaction. This paper surveys some of these uses, and presents a quantitative method for measuring the level of nonverbal synchrony in an interaction.

We have investigated relationships between age, blood pressure and intracellular calcium concentration in platelets from normotensives and hypertensives. In normotensives, there were positive correlations between age and platelet intracellular calcium concentration (r = 0.76, P less than 0.001), age and mean arterial pressure (MAP; r = 0.55, P less than 0.01) and MAP and platelet intracellular calcium concentration (r = 0.45, P less than 0.01). Multiple regression analysis revealed that age was the primary determinant of platelet intracellular calcium concentration in normotensives. The effect of MAP on platelet intracellular calcium concentration when adjusted for age was not significant (P = 0.73). In hypertensives, there was no significant relationship between age and platelet intracellular calcium concentration (r = 0.15, P = 0.43), age and MAP (r = 0.17, P = 0.37) or MAP and platelet intracellular calcium concentration (r = -0.27, P = 0.15). Overall, platelet intracellular calcium concentration was significantly higher in hypertensives than in age-matched normotensives (P less than 0.05). Within the age groups examined, platelet intracellular calcium concentration was significantly higher only in younger hypertensives when compared with controls of a similar mean age (P less than 0.001). Thus, age, in addition to hypertension, is an important determinant of platelet intracellular calcium concentration.

There is a growing realization in the health system that integration of effort may be the best way of ensuring optimal outcomes of management both for clinicians and for people using the health system. It is also hypothesized that the impact of diabetes (chronic disease) and its sequelae could be reduced by the provision of well-organized care, based on agreed evidence-based guidelines for best practice, incorporating patient education and early detection of complication. This paper defines the characteristics of an integrated model of providing care to people with diabetes.

A number of method have been recently proposed in the literature for the encryption of 2-D information using optical systems based on the fractional Fourier fransform, FRT. In this paper a brief review of the methods proposed to date is presented. A measure of the strength/robustness of the level of encryption of the various techniques is proposed and a comparison is carried out between the methods. Optical implementations are discussed. Robustness of system with respect to misalignment and blind decryption are also discussed.

Psychological sense of community (SOC) was proposed to be the central aspect of community psychology by Sarason (1974). At the Society for Community Research and Action conference at Yale in 1999, Sarason was asked by Bob Newbrough why he had formulated the concept of SOC. He stated that as a child during the depression he experienced the terror of being at the point of having no physical and emotional support. Sustained experiences of this kind then form the basis of alienation that individuals and groups in our societies experience. Sarason argued that this was a profound experience and is a considerable risk factor for psychological and social problems. Understanding SOC, thus, is an essential aspect of community psychology.

A numerical scheme, which is interfaced with a general-purpose finite element package for the simulation of resin film infusion process, is presented. The movement of the resin within the film and the impregnation of the fabric preform are modelled simultaneously as a fixed boundary problem. Application of the scheme is demonstrated by simulating the fabrication of a generic L-section. Accepted version