Simultaneous multi-band detection of Low Surface Brightness galaxies with Markovian modelling

We present an algorithm for the detection of Low Surface Brightness (LSB) galaxies in images, called MARSIAA (MARkovian Software for Image Analysis in Astronomy), which is based on multi-scale Markovian modeling. MARSIAA can be applied simultaneously to different bands. It segments an image into a user-defined number of classes, according to their surface brightness and surroundings - typically, one or two classes contain the LSB structures. We have developed an algorithm, called DetectLSB, which allows the efficient identification of LSB galaxies from among the candidate sources selected by MARSIAA. To assess the robustness of our method, the method was applied to a set of 18 B and I band images (covering 1.3 square degrees in total) of the Virgo cluster. To further assess the completeness of the results of our method, both MARSIAA, SExtractor, and DetectLSB were applied to search for (i) mock Virgo LSB galaxies inserted into a set of deep Next Generation Virgo Survey (NGVS) gri-band subimages and (ii) Virgo LSB galaxies identified by eye in a full set of NGVS square degree gri images. MARSIAA/DetectLSB recovered ~20% more mock LSB galaxies and ~40% more LSB galaxies identified by eye than SExtractor/DetectLSB. With a 90% fraction of false positives from an entirely unsupervised pipeline, a completeness of 90% is reached for sources with r_e > 3" at a mean surface brightness level of mu_g=27.7 mag/arcsec^2 and a central surface brightness of mu^0 g=26.7 mag/arcsec^2. About 10% of the false positives are artifacts, the rest being background galaxies. We have found our method to be complementary to the application of matched filters and an optimized use of SExtractor, and to have the following advantages: it is scale-free, can be applied simultaneously to several bands, and is well adapted for crowded regions on the sky.Comment: 39 pages, 18 figures, accepted for publication in A

Self-Development of Competences for Social Inclusion Using the TENCompetence Infrastructure

This paper describes a pilot study centred on the technology-enhanced self-development of competences in lifelong learning education carried out in the challenging context of the Association of Participants Àgora. The pilot study shows that the use of the TENCompetence infrastructure, i.e. in this case the Personal Development Planner tool, provides various kinds of benefits for adult participants with low educational profiles and who are traditionally excluded from the use of innovative learning technologies and the knowledge society. The selforganized training supported by the PDP tool aims at allowing the learners to create and control their own learning plans based on their interests and educational background including informal and non-formal experiences. In this sense, the pilot participants had the opportunity to develop and improve their competences in English language (basic and advanced levels) and ICT competence profiles which are mostly related to functional and communicative skills. Besides, the use of the PDP functionalities, such as the self-assessment, the planning and the self-regulating elements allowed the participants to develop reflective skills. Pilot results also provide indications for future developments in the field of technology support for self-organized learners. The paper introduces the context and the pilot scenario, indicates the evaluation methodology applied and discusses the most significant findings derived from the pilot study

First report of Quaternary mammals from the Qalehjough area, Lut Desert, Eastern Iran

Taxonomic study of Quaternary mammal remains from the Qalehjough fossil site, eastern Iran, has resulted in the identification of two mammal orders, Artiodactyla and Perissodactyla, with four families and six taxa. Of particular note was the recovery of Stephanorhinus and a caballoid horse. These remains have provided the first opportunity to examine Late Quaternary faunal assemblages in the northern parts of the Lut Desert, eastern Iran. The Qalehjough faunal assemblage documents some zoogeographic characteristics of the eastern Iranian Plateau, and suggests that palaeoenvironments in this part of Iran during the Pleistocene were more humid and wooded than today. The disappearance of rhinoceroses and caballoid horses from this region is most likely a result of climate change and concomitant habitat loss

Color display for multiwavelength astronomical images

This paper proposes a new approach for the color display of multispectral/hyperspectral images. The color representation of such data becomes problematic when the number of bands is higher than three, i.e. the basic RGB (Red, Green, Blue) representation is not straightforward. Here we employ a technique that uses a segmentation map, like an a priori information, and then compute a Factorial Discriminant Analysis (Fischer analysis) in order to allow, at best, a distribution of the information in the color space HSV (Hue, Saturation, Value). The information collected from the segmentation map (where each pixel is associated with class) has been shown to be advantages in the representation of the images through the results obtained on increasing size image collections in the framework of astronomical images. This method can easily be applied to other domains such as polarimetric or remote sensing imagery.Cet article propose une nouvelle méthode de représentation et de visualisation en couleur d'images multispectrales ou hyperspectrales. Le problème de la visualisation de telles données est en effet problématique dès que le nombre de bandes spectrales est supérieur à trois, i.e., la représentation triviale RVB (Rouge, Vert, Bleu) n'est plus directe. Le principe consiste ici à utiliser une carte de segmentation préalablement obtenue, a priori, et à réaliser une analyse factorielle discriminante permettant de distribuer au mieux l'information dans l'espace des couleurs TSL (Teinte, Saturation, Luminance). L'information apportée par la carte de segmentation (chaque site est associé à une classe) peut se révéler judicieuse comme le montrent les résultats obtenus sur des lots d'images de tailles croissantes dans le cadre de l'imagerie astronomique. Cette méthode est générale et s'applique également à d'autres domaines manipulant des images multicomposantes ou multivariées comme en télédétection ou en imagerie polarimétrique

The Lives of Creatures Obscure, Misunderstood, and Wonderful: A Volume in Honour of Ken Aplin 1958-2019

Kenneth Peter Aplin (1958-2019) was one of Australia's leading vertebrate systematists, well known as an anatomist, mammalogist, herpetologist, palaeontologist, and archaeologist. Of all the many groups of animals that he studied, he was most passionate about the genus Rattus, among the most diverse and successful of all modern mammalian genera. Ken developed an unusually acute 'eye' for distinguishing taxa in vertebrate groups often considered very challenging to systematists, like Rattus. This skill was borne in part of extensive fieldwork, especially in New Guinea, Australia, and across Asia. This let him encounter many different groups of animals firsthand and to develop a remarkable ability for understanding them on their own ground. Where most mammalogists would bring rat traps, Ken would bring a shovel, and he would get to work in the landscape around him, digging burrows out of the ground to uncover rats that the trapper rarely sees. Of course, his careful work as a systematist and anatomist also sprang from a career spent within the world of natural history museums and their collections, the primary resource that biodiversity scientists use to develop their skills and undertake their work. From his earliest days as a scientist, he also showed an abiding interest in archaeology, and the study of faunal remains in archaeological contexts was a major strand that wove across his career. In this volume, the Australian Museum celebrates the career of an extraordinary fieldworker and museum scientist who made enormous contributions to the study of Asia-Pacific biodiversity, present and past

Orangutans venture out of the rainforest and into the Anthropocene

Conservation benefits from understanding how adaptability and threat interact to determine a taxon’s vulnerability. Recognizing how interactions with humans have shaped taxa such as the critically endangered orangutan (Pongo spp.) offers insights into this relationship. Orangutans are viewed as icons of wild nature, and most efforts to prevent their extinction have focused on protecting minimally disturbed habitat, with limited success. We synthesize fossil, archeological, genetic, and behavioral evidence to demonstrate that at least 70,000 years of human influence have shaped orangutan distribution, abundance, and ecology and will likely continue to do so in the future. Our findings indicate that orangutans are vulnerable to hunting but appear flexible in response to some other human activities. This highlights the need for a multifaceted, landscape-level approach to orangutan conservation that leverages sound policy and cooperation among government, private sector, and community stakeholders to prevent hunting, mitigate human-orangutan conflict, and preserve and reconnect remaining natural forests. Broad cooperation can be encouraged through incentives and strategies that focus on the common interests and concerns of different stakeholders. Orangutans provide an illustrative example of how acknowledging the long and pervasive influence of humans can improve strategies to preserve biodiversity in the Anthropocene

Species identification of Australian marsupials using collagen fingerprinting

The study of faunal remains from archaeological sites is often complicated by the presence of large numbers of highly fragmented, morphologically unidentifiable bones. In Australia, this is the combined result of harsh preservation conditions and frequent scavenging by marsupial carnivores. The collagen fingerprinting method known as zooarchaeology by mass spectrometry (ZooMS) offers a means to address these challenges and improve identification rates of fragmented bones. Here, we present novel ZooMS peptide markers for 24 extant marsupial and monotreme species that allow for genus-level distinctions between these species. We demonstrate the utility of these new peptide markers by using them to taxonomically identify bone fragments from a nineteenth-century colonial-era pearlshell fishery at Bandicoot Bay, Barrow Island. The suite of peptide biomarkers presented in this study, which focus on a range of ecologically and culturally important species, have the potential to significantly amplify the zooarchaeological and paleontological record of Australia.1. Introduction 2. Material and methods 2.1. Materials 2.1.1. Modern reference specimens 2.1.2. Archaeological specimens 2.2. Collagen extraction 2.3. Matrix-assisted laser desorption/ionization–tandem time of flight mass spectrometry 2.4. Liquid chromatography with tandem mass spectrometry 2.5. Identification and confirmation of biomarkers 3. Results 3.1. Novel ZooMS peptide markers 3.2. Marsupial versus monotreme ZooMS markers 3.3. Marsupial ZooMS markers 3.4. Using ZooMS to identify macropods 3.5. Collagen fingerprinting of archaeological specimens 4. Discussion 4.1. ZooMS insights at Bandicoot Bay 4.2. Comparison to published markers 4.3. Challenges and future prospect

A taxonomic and taphonomic study of Pleistocene fossil deposits from the western Nefud Desert, Saudi Arabia

Over the past decade, a growing interest has developed on the archaeology, palaeontology, and palaeoenvironments of the Arabian Peninsula. It is now clear that hominins repeatedly dispersed into Arabia, notably during pluvial interglacial periods when much of the peninsula was characterised by a semiarid grassland environment. During the intervening glacial phases, however, grasslands were replaced with arid and hyperarid deserts. These millennial-scale climatic fluctuations have subjected bones and fossils to a dramatic suite of environmental conditions, affecting their fossilisation and preservation. Yet, as relatively few palaeontological assemblages have been reported from the Pleistocene of Arabia, our understanding of the preservational pathways that skeletal elements can take in these types of environments is lacking. Here, we report the first widespread taxonomic and taphonomic assessment of Arabian fossil deposits. Novel fossil fauna are described and overall the fauna are consistent with a well-watered semiarid grassland environment. Likewise, the taphonomic results suggest that bones were deposited under more humid conditions than present in the region today. However, fossils often exhibit significant attrition, obscuring and fragmenting most finds. These are likely tied to wind abrasion, insolation, and salt weathering following fossilisation and exhumation, processes particularly prevalent in desert environments