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We present the most sensitive and detailed view of the neutral hydrogen (
${\rm H\small I}$
) emission associated with the Small Magellanic Cloud (SMC), through the combination of data from the Australian Square Kilometre Array Pathfinder (ASKAP) and Parkes (Murriyang), as part of the Galactic Australian Square Kilometre Array Pathfinder (GASKAP) pilot survey. These GASKAP-HI pilot observations, for the first time, reveal
${\rm H\small I}$
in the SMC on similar physical scales as other important tracers of the interstellar medium, such as molecular gas and dust. The resultant image cube possesses an rms noise level of 1.1 K (
$1.6\,\mathrm{mJy\ beam}^{-1}$
)
$\mathrm{per}\ 0.98\,\mathrm{km\ s}^{-1}$
spectral channel with an angular resolution of
$30^{\prime\prime}$
(
${\sim}10\,\mathrm{pc}$
). We discuss the calibration scheme and the custom imaging pipeline that utilises a joint deconvolution approach, efficiently distributed across a computing cluster, to accurately recover the emission extending across the entire
${\sim}25\,\mathrm{deg}^2$
field-of-view. We provide an overview of the data products and characterise several aspects including the noise properties as a function of angular resolution and the represented spatial scales by deriving the global transfer function over the full spectral range. A preliminary spatial power spectrum analysis on individual spectral channels reveals that the power law nature of the density distribution extends down to scales of 10 pc. We highlight the scientific potential of these data by comparing the properties of an outflowing high-velocity cloud with previous ASKAP+Parkes
${\rm H\small I}$
test observations.
We present the first Faraday rotation measure (RM) grid study of an individual low-mass cluster—the Fornax cluster—which is presently undergoing a series of mergers. Exploiting commissioning data for the POlarisation Sky Survey of the Universe’s Magnetism (POSSUM) covering a ${\sim}34$ square degree sky area using the Australian Square Kilometre Array Pathfinder (ASKAP), we achieve an RM grid density of ${\sim}25$ RMs per square degree from a 280-MHz band centred at 887 MHz, which is similar to expectations for forthcoming GHz-frequency ${\sim}3\pi$-steradian sky surveys. These data allow us to probe the extended magnetoionic structure of the cluster and its surroundings in unprecedented detail. We find that the scatter in the Faraday RM of confirmed background sources is increased by $16.8\pm2.4$ rad m−2 within 1$^\circ$ (360 kpc) projected distance to the cluster centre, which is 2–4 times larger than the spatial extent of the presently detectable X-ray-emitting intracluster medium (ICM). The mass of the Faraday-active plasma is larger than that of the X-ray-emitting ICM and exists in a density regime that broadly matches expectations for moderately dense components of the Warm-Hot Intergalactic Medium. We argue that forthcoming RM grids from both targeted and survey observations may be a singular probe of cosmic plasma in this regime. The morphology of the global Faraday depth enhancement is not uniform and isotropic but rather exhibits the classic morphology of an astrophysical bow shock on the southwest side of the main Fornax cluster, and an extended, swept-back wake on the northeastern side. Our favoured explanation for these phenomena is an ongoing merger between the main cluster and a subcluster to the southwest. The shock’s Mach angle and stand-off distance lead to a self-consistent transonic merger speed with Mach 1.06. The region hosting the Faraday depth enhancement also appears to show a decrement in both total and polarised radio emission compared to the broader field. We evaluate cosmic variance and free-free absorption by a pervasive cold dense gas surrounding NGC 1399 as possible causes but find both explanations unsatisfactory, warranting further observations. Generally, our study illustrates the scientific returns that can be expected from all-sky grids of discrete sources generated by forthcoming all-sky radio surveys.
Decision-makers need readily accessible tools to understand the potential impacts of alternative policies on forest cover and greenhouse gas (GHG) emissions and to develop effective policies to meet national and international targets for biodiversity conservation, sustainable development and climate change mitigation. Land change modelling can support policy decisions by demonstrating potential impacts of policies on future deforestation and GHG emissions. We modelled land change to explore the potential impacts of expert-informed scenarios on deforestation and GHG emissions, specifically CO2 emissions, in the Ankeniheny–Zahamena Corridor in eastern Madagascar. We considered four scenarios: business as usual; effective conservation of protected areas; investment in infrastructure; and agricultural intensification. Our results highlight that effective forest conservation could deliver substantial emissions reductions, while infrastructure development will likely cause forest loss in new areas. Agricultural intensification could prevent additional forest loss if it reduced the need to clear more land while improving food security. Our study demonstrates how available land change modelling tools and scenario analyses can inform land-use policies, helping countries reconcile economic development with forest conservation and climate change mitigation commitments.
Massive stars are some of the most important objects in the Universe, shaping the evolution of galaxies, creating chemical elements, and hence shaping the evolution of the Universe. However, the processes by which they form, and how they shape their environment during their birth processes, are not well understood. We are using NH3 data from the “The H2O Southern Galactic Plane Survey” (HOPS) to define the positions of dense cores/clumps of gas in the southern Galactic plane that are likely to form stars. We did a comparative study with different methods for finding clumps and found Fellwalker to be the best for this dataset. We detected ~ 500 clumps with mean kinetic temperature ~ 20 K and virial mass ~ 680 solar masses.
Although Europeans had been receiving reports about Buddhism since the thirteenth century – from Marco Polo, papal envoys, Jesuits, and Asian specialists – it was not until the midcentury that European intellectuals generally began to be aware that there was at least one major form of religion, Theravada Buddhism, which was atheistic. Nevertheless, the general tendency throughout the century was to conceive of the “essence of religion” as belief in supernatural deities and to regard monotheism as the most highly developed form of it. Consequently, most of the challenges to religion in the nineteenth century, like those in the seventeenth and eighteenth, tended to be challenges to theism generally and to the culturally predominant forms of it, Christianity and Judaism, particularly. And it will be these challenges with which we shall be primarily concerned.
What distinguishes the nineteenth from previous centuries is the extraordinary variety of these challenges. The attacks of the seventeenth and eighteenth centuries were primarily philosophical and rationalistic, and the arguments swirled around such age-old issues as the cogency of the arguments for the existence of God, the possibility of miracles, and whether the existence of evil is compatible with the reality of an omnipotent and benevolent deity. But the challenges to religion in the nineteenth century were launched not only by philosophers but by political revolutionaries, liberal reformers, utilitarian moralists, positivistic social theorists, agnostics, and a variety of scholars working in the new specialized and increasingly professionalized forms of knowledge: anthropology, biology, geology, history, psychology, and sociology.
Objective: Depression is suggested to involve disturbances in cholinergic as well as glutamatergic pathways, particularly the N-methyl-d-aspartate receptor-mediated release of nitric oxide (NO) and cyclic guanosine monophosphate (cGMP). The aim of this study was to determine whether the Flinders Sensitive Line (FSL) rat, a genetic model of depression, presents with corticolimbic changes in basal acetylcholine (ACh) levels and NO/cGMP signalling.
Methods: Basal levels of nitrogen oxides (NOx) and both basal and l-arginine-stimulated nitric oxide synthase (NOS) formation of l-citrulline were analysed in hippocampus and frontal cortex in FSL and control Flinders resistant line (FRL) rats by fluorometric and electrochemical high-performance liquid chromatography, respectively. In addition, ACh and cGMP levels were analysed by liquid chromatography tandem mass spectrometry and radioimmunoassay, respectively.
Results: Significantly elevated frontal cortical but reduced hippocampal ACh levels were observed in FSL versus FRL rats. Basal cGMP levels were significantly reduced in the frontal cortex, but not hippocampus, of FSL rats without changes in NOx and l-citrulline, suggesting that the reduction of cGMP follows through an NOS-independent mechanism.
Conclusions: These data confirm a bidirectional change in ACh in the frontal cortex and hippocampus of the FSL rat, as well as provide evidence for a frontal cortical ACh-cGMP interaction in the depressive-like behaviour of the FSL rat.
Poor diet in childhood increases risk of obesity but the relationship between access to food and children’s food choice is underexplored. We determined relationships between distance to and density of food outlets on children’s food choice.
Design
Children (n 1721) aged 9–10 years who participated in a cross-sectional study from a sample of state and private schools across urban and rural areas. Food consumption was reported using a short validated FFQ. A Geographic Information System was used to determine proximity to local food outlets. Multivariable regression analyses were performed to determine associations between food consumption and distance to and density of local food outlets.
Setting
Norfolk, England.
Subjects
Boys (n 754) and girls (n 967) aged 9–10 years.
Results
The impact of distance to or density of food outlets on food choice was small after adjustment. Living further away from a supermarket increased portions of fruit (0·11 portions/week per 1 km increase in distance to nearest supermarket, P < 0·05) and vegetables (0·11 portions/week, P < 0·05) consumed. Living closer to convenience stores was also associated with an increased consumption of crisps, chocolate and white bread. Density of supermarkets was associated with both an increase in vegetable intake (0·31 portions/week, P < 0·05) and unhealthy foods.
Conclusions
Distance to and density of food outlets are both associated with children’s food choice, although the impact appears to be small and the relationship is complex. However, the effects of individual foods combined could be important, particularly as even small differences in intake can impact on body weight over time.
Ludwig Feuerbach (1804–72) was the fourth of eight children in one of the most distinguished German families of the time. Deeply religious as a youth, he entered Heidelberg in 1823 in order to study Christian theology. But there he came under the influence of a well-known Hegelian theologian. Impressed by the intellectual grandeur of Hegelianism he decided to transfer to Berlin where Hegel taught, although he gave his father the impression that he wanted to study theology with the famous Protestant theologian Friedrich Schleiermacher. Because of financial reasons, he transferred to Erlangen in 1826 where, after completing his dissertation, he was made a Privatdozent. There he lectured on the history of modern philosophy.
In 1830 and against the advice of his father, he published anonymously a book entitled Thoughts on Death and Immortality, which argued that the most authentic religious faith would not contain the traditional Christian beliefs in a personal God and in personal immortality. The text, unfortunately, was accompanied by a series of derogatory epigrams directed against pietism. The book was censored by the authorities and Feuerbach was fired from the university. He married in 1837 but, unable to find academic employment, retired to a remote village near Ansbach where his wife's father owned a porcelain factory. There, in relative isolation except for trips to visit friends, he devoted his life to writing. The youngest of his two daughters died a very painful death aged three and Feuerbach never recovered from what he regarded as the senseless death of this infant.
LOFAR (Low Frequency Array) is an innovative radio telescope optimized for the frequency range 30–240 MHz. The telescope is realized as a phased aperture array without any moving parts. Digital beam forming allows the telescope to point to any part of the sky within a second. Transient buffering makes retrospective imaging of explosive short-term events possible. The scientific focus of LOFAR will initially be on four key science projects (KSPs): (i) Detection of the formation of the very first stars and galaxies in the universe during the so-called epoch of reionization by measuring the power spectrum of the neutral hydrogen 21-cm line (Shaver et al. 1999) on the ∼ 5′ scale; (ii) Low-frequency surveys of the sky with of order 108 expected new sources; (iii) All-sky monitoring and detection of transient radio sources such as γ-ray bursts, X-ray binaries, and exo-planets (Farrell et al. 2004); and (iv) Radio detection of ultra-high energy cosmic rays and neutrinos (Falcke & Gorham 2003) allowing for the first time access to particles beyond 1021 eV (Scholten et al. 2006). Apart from the KSPs open access for smaller projects is also planned. Here we give a brief description of the telescope.
The antifeedant activities of Piper guineense Schum et Thonn (Piperaceae), Aframomum melegueta (Rosk) K. Schum (Zingiberaceae), Aframomum citratum (Pareira) K. Schum (Zingiberaceae) and Afrostyrax kamerunensis Perkins and Gilg (Huaceae) seed extracts were investigated in laboratory dual- and no-choice bioassays using third-instar Spodoptera littoralis (Boisduval) larvae. In the dual-choice test, the hexane and methanol extracts of A. melegueta showed potent dose-dependent antifeedant activity at concentrations of ≥300 ppm and the water extract at ≥500 ppm, as illustrated by significantly lower leaf consumptions. Aframomum citratum methanol and water extracts exhibited antifeedant activity at ≥300 and ≥1000 ppm, respectively, but the hexane and ethanol extracts did not affect feeding at any concentration. Piper guineense ethanol and water extracts showed dose-dependent antifeedant effects at ≥300 and ≥500 ppm, respectively, and the methanol extract was active only at 1000 ppm. None of the extracts of the highly aromatic A. kamerunensis exhibited antifeedant activity at any of the tested concentrations. In the no-choice bioassays, extracts with antifeedant activity in the dual-choice tests also showed dose-dependent feeding inhibition. The hexane and methanol extracts of A. melegueta were effective in the no-choice tests at ≥100 and ≥500 ppm, respectively, and the water extract at ≥300 ppm. Similarly, the A. citratum water and methanol extracts were active at ≥500 ppm and the P. guineense water and ethanol extracts at ≥100 ppm. GC/MS chromatography of A. melegueta hexane and methanol extracts revealed volatile constituents with known anti-insect activity. The hexane and methanol extracts of A. melegueta, the methanol extract of A. citratum and the water and ethanol extracts of P. guineense may have potential for use by subsistence farmers.