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Future detection of high-redshift gamma-ray bursts (GRBs) will be an important tool for studying the early Universe. Fast and accurate redshift estimation for detected GRBs is key for encouraging rapid follow-up observations by ground- and space-based telescopes. Low-redshift dusty interlopers pose the biggest challenge for GRB redshift estimation using broad photometric bands, as their high extinction can mimic a high-redshift GRB. To assess false alarms of high-redshift GRB photometric measurements, we simulate and fit a variety of GRBs using phozzy , a simulation code developed to estimate GRB photometric redshifts, and test the ability to distinguish between high- and low-redshift GRBs when using simultaneously observed photometric bands. We run the code with the wavelength bands and instrument parameters for the Photo-z Infrared Telescope (PIRT), an instrument designed for the Gamow mission concept. We explore various distributions of host galaxy extinction as a function of redshift, and their effect on the completeness and purity of a high-redshift GRB search with the PIRT. We find that for assumptions based on current observations, the completeness and purity range from ∼82 to 88 per cent and from ∼84 to |$\gt 99~{{\ \rm per\ cent}}$|⁠ , respectively. For the priors optimized to reduce false positives, only |$\sim 0.6~{{\ \rm per\ cent}}$| of low-redshift GRBs will be mistaken as a high-redshift one, corresponding to ∼1 false alarm per 500 detected GRBs. [ABSTRACT FROM AUTHOR]

Despite the roles they play in ecosystem function, animals have have long been neglected in the monitoring of ecological restoration. Vertebrate surveys can be time consuming and costly, often requiring multiple methodologies and taxonomic expertise, making comprehensive monitoring cost prohibitive. Here, we evaluate a new method of assessing mammal and bird diversity through the genetic identification of scat collections. Using DNA metabarcoding of scat collections from three bioregions, we generated bird and mammalian assemblage data and distinguished between sites with different restoration histories. However, scat detectability was affected by environmental conditions (e.g. rainfall and vegetative cover), suggesting that our approach is most applicable at certain times of year or in arid (or semi-arid) environments with rocky soils, where conditions are favourable for scat preservation. Taken together these data provide a pathway to: plan, monitor and establish best-practice when restoring landscapes and add to the growing body of literature on the value of DNA metabarcoding in biomonitoring applications. [ABSTRACT FROM AUTHOR]

During two independent fauna surveys, rock-wallaby (Petrogale) scats were recorded from caves located outside the current known Petrogale distribution. Scats collected from Desert Queen Baths (Little Sandy Desert, Western Australia, 2012), and the Barr Smith Range (Murchison, Western Australia, 2015) were genetically analysed and a follow-up motion camera survey confirmed an extant rock-wallaby population at Desert Queen Baths. The combination of sampling techniques overcame the detection difficulties associated with rare and cryptic taxa, and together were important in establishing the presence of Petrogale lateralis from regions where the species has been poorly documented. At both locations, P. lateralis scats were recorded from deep caves situated close to permanent water, reflecting the species’ physiological constraints in the arid zone. These records represent significant range extensions of a highly threatened macropod. [ABSTRACT FROM AUTHOR]

Relaxin is a polypeptide hormone involved in pregnancy and lactation. It is mainly secreted by the corpus luteum and placenta, but is expressed in a number of other tissues, including heart and brain. Within the brain, relaxin is expressed in the olfactory and limbic systems, the cortex and the hypothalamic arcuate nucleus (ARC). Its cognate receptor, relaxin family peptide receptor 1 (RXFP1), is also widely expressed in the brain, including the hypothalamic ARC and paraventricular nucleus (PVN), areas important in appetite regulation. The aim of this study was to investigate whether relaxin influences food intake through central hypothalamic circuits. The human form of relaxin, human relaxin-2 (H2) was administered centrally and peripherally to male Wistar rats and food intake measured. Behaviour was also assessed. Intracerebroventricular (ICV) administration of H2 significantly decreased 1-h food intake in the early dark phase [2.95 ± 0.45 g (saline) vs. 0.95 ± 0.18 g (180 pmol H2), p < 0.001]. ICV administration of H2 decreased feeding behaviour and increased grooming and headdown behaviour. Intraparaventricular injections of H2 significantly decreased 1-h food intake in the early dark phase [3.13 ± 0.35 g (saline) vs. 1.35 ± 0.33 g (18 pmol H2), p < 0.01, 1.61 ± 0.31 g (180 pmol H2), p < 0.05 and 1.23 ± 0.32 g (540 pmol H2), p < 0.001]. Intraperitoneal (IP) administration of H2 significantly decreased 1-h food intake in the early dark phase [4.63 ± 0.46 g (vehicle) vs. 3.08 ± 0.15 g (66 nmol H2), p < 0.01, 3.00 ± 0.17 g (200 nmol H2), p < 0.01 and 2.26 ± 0.36 g (660 nmol H2), p < 0.001]. Central and peripheral administration of H2 reduces the food intake in rats. This effect may be mediated via the PVN and/or other brain regions. [ABSTRACT FROM AUTHOR]

Background: The thyroid hormone derivative 3-iodothyronamine (T1AM), an endogenous biogenic amine, is a potent agonist of the G protein–coupled trace amine-associated receptor 1 (TAAR1). T1AM is present in rat brain, and TAAR1 is expressed in hypothalamic nuclei associated with the regulation of energy homeostasis. Aim: The aim of this study was to determine the effects of T1AM on food intake in rodents. Methods: We determined the effect of (i) intraperitoneal (i.p.) administration of T1AM on food intake, oxygen consumption (VO2) and locomotor activity in mice; (ii) intracerebroventricular (ICV) injection of T1AM on food intake in male rats; (iii) c-fos expression following ventricular administration of T1AM in male rats; and (iv) direct injection of T1AM into the arcuate nucleus (ARC) of male rats on food intake. Results: (i) T1AM (4 nmol/kg) significantly increased food intake following i.p. injection in mice but had no effect on VO2 or locomotor activity. (ii) ICV administration of T1AM (1.2 nmol/kg) significantly increased food intake in male rats. (iii) Intraventricular administration of T1AM significantly increased c-fos expression in the ARC of male rats. (iv) Direct administration of T1AM (0.12, 0.4 and 1.2 nmol/kg) into the ARC of male rats significantly increased food intake. Conclusion: These data suggest that T1AM is an orexigenic factor that may act through the ARC to increase food intake in rodents. [ABSTRACT FROM AUTHOR]

Background: SR141716 has been shown to significantly inhibit food intake and reduce body weight by antagonizing CB1 receptors. The gut hormones peptide YY3–36 (PYY3–36) and oxyntomodulin (OXM) inhibit food intake through Y2 and Glucagon-Like-Peptide (GLP)-1 receptors respectively. Objective: To determine the effects of co-administration of SR141716 with either PYY3–36 or OXM in mice on food intake. Methods: Mice (n = 14 per group) were fasted for 16 h prior to study days and given two intraperitoneal injections: study 1, vehicle–saline, SR141716–saline, vehicle–PYY3–36 or SR141716–PYY3–36; study 2: vehicle–saline, SR141716–saline, vehicle–OXM or SR141716–OXM. Food was returned and measured following injections. Results: Co-administration of SR141716–PYY3–36 or SR141716–OXM showed greater inhibition in food intake when compared with administration of SR141716, PYY3–36 or OXM alone. Conclusion: Our data show that SR141716 in combination with PYY3–36 or OXM reduces food intake additively in mice. [ABSTRACT FROM AUTHOR]

The insulin superfamily, characterized by common disulphide bonds, includes not only insulin but also insulin-like peptides such as relaxin-1 and relaxin-3. The actions of relaxin-3 are largely unknown, but recent work suggests a role in regulation of food intake. Relaxin-3 mRNA is highly expressed in the nucleus incertus, which has extensive projections to the hypothalamus, and relaxin immunoreactivity is present in several hypothalamic nuclei. In the rat, relaxin-3 binds and activates both relaxin family peptide receptor 1, which also binds relaxin-1, and a previously orphaned G protein-coupled receptor, RXFP3. These receptors are extensively expressed in the hypothalamus. The aims of these studies were twofold: 1) map the hypothalamic site(s) of the orexigenic action of relaxin-3 and 2) examine the site(s) of neuronal activation following central relaxin-3 administration. After microinjection into hypothalamic sites, human relaxin-3 (H3; 180 pmol) significantly stimulated 0- to 1-h food intake in the supraoptic nucleus (SON), arcuate nucleus (ARC), and the anterior preoptic area (APOA) [SON 0.4 ± 0.2 (vehicle) vs. 2.9 ± 0.5 g (H3), P < 0.001; ARC 0.7 ± 0.3 (vehicle) vs. 2.7 ± 0.2 g (H3), P < 0.05; and APOA 0.8 ± 0.1 (vehicle) vs. 2.2 ± 0.2 g (H3), P < 0.051. Cumulative food intake was significantly increased ⩽8 h following administration into the SON and 4 h into the APOA. A significant increase in Fos-like immunoreactivity was seen in the SON following central relaxin-3 administration. Relaxin-3 stimulates feeding in several hypothalamic nuclei, and these studies provide additional support for relaxin-3 as an important peptide in appetite regulation. [ABSTRACT FROM AUTHOR]

ABSTRACT Constellation-X is the X-ray equivalent of the Keck Telescope. When observations begin towards the end of the next decade, they will mark the start of a new era with high resolution X-ray spectra obtained for all classes of X-ray sources over a wide range of luminosity cud distance. With its increased capabilities, Constellation-X will address many fundamental astrophysics questions such as observing the formation and evolution of clusters of galaxies; constraining the Baryon content of the Universe; determining the spin and mass of super massive black holes in AGN; and probing strong gravity in the vicinity of black holes. [ABSTRACT FROM AUTHOR]

The various types and classes of X-ray binary are reviewed highlighting recent results. The high mass X-ray binaries (HMXRBs) can be used to probe the nature of the mass loss from the OB star in these systems. Absorption measurements through one orbital cycle of the supergiant system X1700-37 are well modelled by a radiation, driven wind and also require a gas stream trailing behind the X-ray source. In Cen X-3 the gas stream is accreted by the X-ray source via an accretion disk. Changes in the gas stream can cause the disk to thicken and the disk to obscure the X-ray source. How close the supergiant is to corotation seems to be as much a critical factor in these systems as how close it is to filling its Roche lobe. In the Be star X-ray binaries a strong correlation between the neutron stars rotation period and its orbital period has been explained as due to the neutron star being immersed in a dense, slow moving equatorial wind from the Be star. For the X-ray pulsars in the transient Be X-ray binaries a centrifugal barrier to accretion is important in determining the X-ray lightcurve and the spin evolution. The X-ray orbital modulations from the low mass X-ray binaries. LMXRBs, include eclipses by the companion and/or periodic dipping behaviour from structure at the edge of the disk. The corresponding optical modulations show a smooth sinusoidal like component and in some cases a sharp eclipse by the companion. The orbital period of the LMXRB XB1916-05 is 1% longer in the optical compared to that given by the X-ray dip period. The optical period has been interpreted as the orbital period, but this seems inconsistent with the well established view of the origin of the X-ray modulations in LMXRB. A new model is presented that assumes the X-ray dip period is the true orbital period. The 5.2 h eclipsing LMXRB XB2129-47 recently entered a low state and optical observations unexpectedly reveal an F star which is too big to fit into the binary. This is probably the first [ABSTRACT FROM AUTHOR]