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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