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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]

Author(s): N. Gehrels (corresponding author) [1]; C. L. Sarazin [2]; P. T. O'Brien [3]; B. Zhang [4]; L. Barbier [1]; S. D. Barthelmy [1]; A. Blustin [5]; D. N. Burrows [...]

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]

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 ecological restoration of ecosystem services and biodiversity is a key intervention used to reverse the impacts of anthropogenic activities such as mining. Assessment of the performance of restoration against completion criteria relies on biodiversity monitoring. However, monitoring usually overlooks soil microbial communities (SMC), despite increased awareness of their pivotal role in many ecological functions. Recent advances in cost, scalability and technology has led to DNA sequencing being considered as a cost-effective biological monitoring tool, particularly for otherwise difficult to survey groups such as microbes. However, such approaches for monitoring complex restoration sites such as post-mined landscapes have not yet been tested. Here we examine bacterial and fungal communities across chronosequences of mine site restoration at three locations in Western Australia to determine if there are consistent changes in SMC diversity, community composition and functional capacity. Although we detected directional changes in community composition indicative of microbial recovery, these were inconsistent between locations and microbial taxa (bacteria or fungi). Assessing functional diversity provided greater understanding of changes in site conditions and microbial recovery than could be determined through assessment of community composition alone. These results demonstrate that high-throughput amplicon sequencing of environmental DNA (eDNA) is an effective approach for monitoring the complex changes in SMC following restoration. Future monitoring of mine site restoration using eDNA should consider archiving samples to provide improved understanding of changes in communities over time. Expansion to include other biological groups (e.g. soil fauna) and substrates would also provide a more holistic understanding of biodiversity recovery., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)