Grounded: characterising the market exit of European low cost airlines

The aim of this paper is to undertake a comprehensive study of LCC market entry and exit in Europe between 1992 and 2012. In the 20 year period between 1992 and 2012, 43 low cost carriers (LCCs) have taken advantage of the progressive liberalisation of the European aviation market and commenced scheduled flight operations within the continent. Of these 43, only 10 remain operational, a failure rate of 77%. This paper contributes to extant literature on LCCs by examining the market entry, business practices, operating longevity and fate of failed operators to characterise European LCC market exit. Drawing on the findings of a detailed continental-wide study, the paper identifies that an airline’s start-up date, the nature and size of its operation and the size and composition of its aircraft fleet are key factors which influence LCC success and failure. The implications for both European and emerging LCC markets are discussed

Поліетилен як наймасовіша пластмаса у виробництві упаковки

Delta/Notch (Dl/N) signalling is involved in the gene regulatory network underlying the segmentation process in vertebrates and possibly also in annelids and arthropods, leading to the hypothesis that segmentation may have evolved in the last common ancestor of bilaterian animals. Because of seemingly contradicting results within the well-studied arthropods, however, the role and origin of Dl/N signalling in segmentation generally is still unclear. In this study, we investigate core components of Dl/N signalling by means of gene expression analysis in the onychophoran Euperipatoides kanangrensis, a close relative to the arthropods. We find that neither Delta or Notch nor any other investigated components of its signalling pathway are likely to be involved in segment addition in onychophorans. We instead suggest that Dl/N signalling may be involved in posterior elongation, another conserved function of these genes. We suggest further that the posterior elongation network, rather than classic Dl/N signalling, may be in the control of the highly conserved segment polarity gene network and the lower-level pair-rule gene network in onychophorans. Consequently, we believe that the pair-rule gene network and its interaction with Dl/N signalling may have evolved within the arthropod lineage and that Dl/N signalling has thus likely been recruited independently for segment addition in different phyla

Unintended trajectories: liberalization and the geographies of private business flight

The global commercial aviation industry has undergone significant regulatory reform during the last 30 years. This paper explores something of the relationship between air transport liberalization and the growth of private business aviation and suggests that the sector’s development is largely an unintended consequence of the increasingly deregulated operating environment in that it has developed to overcome some of liberalization’s negative impacts, including delays, congestion, and perceptions of poor customer service. We argue that liberalization has created innovative market opportunities for private business aviation and illustrate how the sector’s operating models are facilitating new, as yet largely undocumented, forms of aerial mobility. The paper examines: the advantages of private business aviation over scheduled services; business strategies in the sector, especially the idea of fractional jets; the impact of new technologies, particularly the Very Light Jet (VLJ); and, finally, employs Europe as an example of the spatialities of private business aviation

Ecological innovations in the Cambrian and the origins of the crown group phyla

One contribution of 16 to a discussion meeting issue 'Homology and convergence in nervous system evolution'

The hatching larva of the priapulid worm Halicryptus spinulosus

Despite their increasing evolutionary importance, basic knowledge about the priapulid worms remains limited. In particular, priapulid development has only been partially documented. Following previous description of hatching and the earliest larval stages of Priapulus caudatus, we here describe the hatching larva of Halicryptus spinulosus. Comparison of the P. caudatus and the H. spinulosus hatching larvae allows us to attempt to reconstruct the ground pattern of priapulid development. These findings may further help unravelling the phylogenetic position of the Priapulida within the Scalidophora and hence contribute to the elucidation of the nature of the ecdysozoan ancestor

Expression of collier in the premandibular segment of myriapods: support for the traditional Atelocerata concept or a case of convergence?

<p>Abstract</p> <p>Background</p> <p>A recent study on expression and function of the ortholog of the <it>Drosophila collier </it>(<it>col</it>) gene in various arthropods including insects, crustaceans and chelicerates suggested a <it>de novo </it>function of <it>col </it>in the development of the appendage-less intercalary segment of insects. However, this assumption was made on the background of the now widely-accepted Pancrustacea hypothesis that hexapods represent an in-group of the crustaceans. It was therefore assumed that the expression of <it>col </it>in myriapods would reflect the ancestral state like in crustaceans and chelicerates, i.e. absence from the premandibular/intercalary segment and hence no function in its formation.</p> <p>Results</p> <p>We find that <it>col </it>in myriapods is expressed at early developmental stages in the same anterior domain in the head, the parasegment 0, as in insects. Comparable early expression of <it>col </it>is not present in the anterior head of an onychophoran that serves as an out-group species closely related to the arthropods.</p> <p>Conclusions</p> <p>Our findings suggest either that i) the function of <it>col </it>in head development has been conserved between insects and myriapods, and that these two classes of arthropods may be closely related supporting the traditional Atelocerata (or Tracheata) hypothesis; or ii) alternatively <it>col </it>function could have been lost in early head development in crustaceans, or may indeed have evolved convergently in insects and myriapods.</p

Публікації ХVІІІ - поч. ХХІ ст. про центральноукраїнські археологічні пам’ятки в Ермітажі

(UA) 1764 р. вийшла публікація Г. Міллера про наслідки перших археологічних розкопок в Україні. Виявлений тоді Литий скарб потрапив до Кунсткамери, а потім – до Ермітажу. Наступні автори вивчали, характеризували цю колекцію, виходячи з отриманих нових даних скіфологією. З ’являлася у світ інформація й про інші надходження до Ермітажу з території, яка сьогодні входить до Кіровоградщини. Ці публікації можуть стати певними свідченнями для обґрунтування постановки питання повернення історичних художніх цінностей з-за кордону до музейного фонду України.(EN) In 1764 the publication of G. Muller went out about the consequences of the first archaeological excavations in Ukraine. Poured treasure is educed then got to Cabinet of curiosities, and then to the Hermitage. Next authors studied, characterized this collection, coming from the obtained new data, as scythology. Information was published about other receivabless to the Hermitage from territory that is today included to the Kirovohrad area. These publications can become certain certificates for the ground of statement of a question of return of historical artistic values in the museum fund of Ukraine

Expression of myriapod pair rule gene orthologs

Background Segmentation is a hallmark of the arthropods; most knowledge about the molecular basis of arthropod segmentation comes from work on the fly Drosophila melanogaster. In this species a hierarchic cascade of segmentation genes subdivides the blastoderm stepwise into single segment wide regions. However, segmentation in the fly is a derived feature since all segments form virtually simultaneously. Conversely, in the vast majority of arthropods the posterior segments form one at a time from a posterior pre-segmental zone. The pair rule genes (PRGs) comprise an important level of the Drosophila segmentation gene cascade and are indeed the first genes that are expressed in typical transverse stripes in the early embryo. Information on expression and function of PRGs outside the insects, however, is scarce. Results Here we present the expression of the pair rule gene orthologs in the pill millipede Glomeris marginata (Myriapoda: Diplopoda). We find evidence that these genes are involved in segmentation and that components of the hierarchic interaction of the gene network as found in insects may be conserved. We further provide evidence that segments are formed in a single-segment periodicity rather than in pairs of two like in another myriapod, the centipede Strigamia maritima. Finally we show that decoupling of dorsal and ventral segmentation in Glomeris appears already at the level of the PRGs. Conclusions Although the pair rule gene network is partially conserved among insects and myriapods, some aspects of PRG interaction are, as suggested by expression pattern analysis, convergent, even within the Myriapoda. Conserved expression patterns of PRGs in insects and myriapods, however, may represent ancestral features involved in segmenting the arthropod ancestor

Laser Chemosensor with Rapid Responsivity and Inherent Memory Based on a Polymer of Intrinsic Microporosity

This work explores the use of a polymer of intrinsic microporosity (PIM-1) as the active layer within a laser sensor to detect nitroaromatic-based explosive vapors. We show successful detection of dinitrobenzene (DNB) by monitoring the real-time photoluminescence. We also show that PIM-1 has an inherent memory, so that it accumulates the analyte during exposure. In addition, the optical gain and refractive index of the polymer were studied by amplified spontaneous emission and variable-angle ellipsometry, respectively. A second-order distributed feedback PIM-1 laser sensor was fabricated and found to show an increase in laser threshold of 2.5 times and a reduction of the laser slope efficiency by 4.4 times after a 5-min exposure to the DNB vapor. For pumping at 2 times threshold, the lasing action was stopped within 30 s indicating that PIM-1 has a very fast responsivity and as such has a potential sensing ability for ultra-low-concentration explosives

Molecular evidence for a single origin of ultrafiltration-based excretory organs

Under embargo until: 2021-06-23Excretion is an essential physiological process, carried out by all living organisms, regardless of their size or complexity.1, 2, 3 Both protostomes (e.g., flies and flatworms) and deuterostomes (e.g., humans and sea urchins) possess specialized excretory organs serving that purpose. Those organs exhibit an astonishing diversity, ranging from units composed of just few distinct cells (e.g., protonephridia) to complex structures, built by millions of cells of multiple types with divergent morphology and function (e.g., vertebrate kidneys).4,5 Although some molecular similarities between the development of kidneys of vertebrates and the regeneration of the protonephridia of flatworms have been reported,6,7 the molecular underpinnings of the development of excretory organs have never been systematically studied in a comparative context.4 Here, we show that a set of transcription factors (eya, six1/2, pou3, sall, lhx1/5, and osr) and structural proteins (nephrin, kirre, and zo1) is expressed in the excretory organs of a phoronid, brachiopod, annelid, onychophoran, priapulid, and hemichordate that represent major protostome lineages and non-vertebrate deuterostomes. We demonstrate that the molecular similarity observed in the vertebrate kidney and flatworm protonephridia6,7 is also seen in the developing excretory organs of those animals. Our results show that all types of ultrafiltration-based excretory organs are patterned by a conserved set of developmental genes, an observation that supports their homology. We propose that the last common ancestor of protostomes and deuterostomes already possessed an ultrafiltration-based organ that later gave rise to the vast diversity of extant excretory organs, including both proto- and metanephridia.acceptedVersio