Opinion Mining on Non-English Short Text

As the type and the number of such venues increase, automated analysis of sentiment on textual resources has become an essential data mining task. In this paper, we investigate the problem of mining opinions on the collection of informal short texts. Both positive and negative sentiment strength of texts are detected. We focus on a non-English language that has few resources for text mining. This approach would help enhance the sentiment analysis in languages where a list of opinionated words does not exist. We propose a new method projects the text into dense and low dimensional feature vectors according to the sentiment strength of the words. We detect the mixture of positive and negative sentiments on a multi-variant scale. Empirical evaluation of the proposed framework on Turkish tweets shows that our approach gets good results for opinion mining

Ediacaran developmental biology

Rocks of the Ediacaran System (635–541 Ma) contain fossil evidence for some of the earliest complex macroscopic organisms, many of which have been interpreted as early animals. However, the unusual morphologies of some of these organisms have made it difficult to resolve their biological relationships to modern metazoan groups. Alternative competing phylogenetic interpretations have been proposed for Ediacaran taxa, including algae, fungi, lichens, rhizoid protists, and even an extinct higher-order group (Vendobionta). If a metazoan affinity can be demonstrated for these organisms, as advocated by many researchers, they could prove informative in debates concerning the evolution of the metazoan body axis, the making and breaking of axial symmetries, and the appearance of a metameric body plan. Attempts to decipher members of the enigmatic Ediacaran macrobiota have largely involved study of morphology: comparative analysis of their developmental phases has received little attention. Here we present what is known of ontogeny across the three iconic Ediacaran taxa Charnia masoni, Dickinsonia costata and Pteridinium simplex, together with new ontogenetic data and insights. We use these data and interpretations to re-evaluate the phylogenetic position of the broader Ediacaran morphogroups to which these taxa are considered to belong (rangeomorphs, dickinsoniomorphs and erniettomorphs), and conclude, based on the available evidence, that the affinities of the rangeomorphs and the dickinsoniomorphs lie within Metazoa.F.S.D., P.C.J.D and A.G.L. are funded by the Natural Environment Research Council [NE/L002434/1, NE/P013678/1, NE/L011409/2]; P.C.J.D is also funded by BBSRC [BB/N000919/1], The Royal Society, and a Royal Society Wolfson Research Merit Award

Remarkable insights into the paleoecology of the Avalonian Ediacaran macrobiota

Ediacaran macrofossils from the Avalon Terrane (primarily eastern Newfoundland and the central UK) record some of the earliest large and complex multicellular organisms on Earth. Perhaps the greatest unknown regarding these fossils is their relevance to the early evolutionary history of the Kingdom Animalia. In recent years, new data and discoveries have revealed insights into Ediacaran paleobiology, taxonomic relationships, paleoecology and taphonomy, significantly refining our understanding of Avalonian ecosystems. Here, we summarise recent observational and quantitative studies, and their bearing on the current understanding of Avalonian benthic marine ecosystems. A review of existing knowledge of the biological composition of Avalonian marine assemblages demonstrates that they record densely-populated ecosystems inhabited by a diverse range of organisms, likely representing multiple biological Kingdoms. Appreciation of this diversity, and of the complexities it introduces to paleoecological studies, is vital when considering the relationship between macroevolution and contemporaneous climatic, tectonic and geochemical events. We then summarise current understanding of Avalonian paleoecology. Studies into locomotion, reproduction, feeding strategies, and community structure and succession reveal that these ecosystems were considerably different to Phanerozoic settings. Furthermore, we suggest that Avalonian ecosystems witnessed the appearance of novel nutrient sources, offering new opportunities and niches for benthic organisms. The suggestion that the numerically dominant rangeomorphs were osmotrophic is reviewed and appraised in light of geochemical, morphological, and biological information. Finally, the use of modern ecological metrics in the study of Ediacaran fossil assemblages is assessed. Concerns regarding the interpretation of paleoecological data are outlined in light of current taphonomic and sedimentological understanding, and these cast doubt on previous suggestions that the Avalonian assemblages were largely composed of metazoans. Nevertheless, we emphasise that if treated with necessary caution, paleoecological data can play a significant role in assisting efforts to determine the biological affinities of late Ediacaran macroscopic organisms.Thanks are extended to the editors of Gondwana Research, T. Horscroft and M. Santosh, for inviting this review, and for their patience whilst we completed it. The Parks and Natural Areas Division, Department of Environment and Conservation, Government of Newfoundland and Labrador provided permits to conduct research within the Mistaken Point Ecological Reserve between 2008–2013, whilst the Department of Tourism, Culture and Recreation provided permits for paleontological research in other parts of the Province from 2012–2013. The support of the Portugal Cove South Visitor Center interpreters during our field research was greatly appreciated. This work has been supported by the Natural Environment Research Council [grant numbers NE/I005927/1 to CGK and NE/G523539/1 to EGM]; a Henslow Junior Research Fellowship from Cambridge Philosophical Society to AGL; and the National Geographic Global Exploration Fund [GEFNE 22-11 to AGL]. Field assistance from J. Matthews, J. Stewart, D. Collins, and T. Hearing has been invaluable, and we have enjoyed fruitful discussions on this topic with N. Butterfield, D. McIlroy, J. Hoyal Cuthill, M. Brasier, S. Conway Morris and P. Wilby. The work and support of past and current workers in this field is gratefully acknowledged. B. MacGabhann and one anonymous reviewer are thanked for providing detailed comments that have strengthened this manuscript, whilst S. Jensen and M. Friedman provided helpful feedback on parts of this manuscript assessed as a chapter of AGL's thesis.This is the final published version of an article that was originally published in Gondwana Research, Available online 4 December 2014, doi:10.1016/j.gr.2014.11.00

Supernatants derived from chemotherapy-treated cancer cell lines can modify angiogenesis

BACKGROUND: There is evidence that tumours produce substances such as cytokines and microvesicular bodies bearing bioactive molecules, which support the carcinogenic process. Furthermore, chemotherapy has also been shown to modify these exudates and in doing so, neutralise their tumourigenic influence. METHODS: In the current study, we have investigated the effect of chemotherapy agents on modifying the cytokine profile and microvesicular cargo of supernatants derived from cancer cell lines. In addition, we have explored the effect of these tumour-derived supernatants on angiogenesis, and how chemotherapy can alter the supernatants rendering them less pro-angiogenic. RESULTS: Herein, we show that supernatants contain a rich cocktail of cytokines, a number of which are potent modulators of angiogenesis. They also contain microvesicular bodies containing RNA transcripts that code for proteins involved in transcription, immune modulation and angiogenesis. These supernatants altered intracellular signalling molecules in endothelial cells and significantly enhanced their tubulogenic character; however, this was severely compromised when supernatants from tumours treated with chemotherapy was used instead. CONCLUSION: This study suggests tumour exudates and bioactive material from tumours can influence cellular functions, and that treatment with some chemotherapy can serve to negate these pro-tumourigenic processes

Resolving MISS conceptions and misconceptions: A geological approach to sedimentary surface textures generated by microbial and abiotic processes

The rock record contains a rich variety of sedimentary surface textures on siliciclastic sandstone, siltstone and mudstone bedding planes. In recent years, an increasing number of these textures have been attributed to surficial microbial mats at the time of deposition, resulting in their classification as microbially induced sedimentary structures, or MISS. Research into MISS has developed at a rapid rate, resulting in a number of misconceptions in the literature. Here, we attempt to rectify these MISS misunderstandings. The first part of this paper surveys the stratigraphic and environmental range of reported MISS, revealing that contrary to popular belief there are more reported MISS-bearing rock units of Phanerozoic than Precambrian age. Furthermore, MISS exhibit a pan-environmental and almost continuous record since the Archean. Claims for the stratigraphic restriction of MISS to intervals prior to the evolution of grazing organisms or after mass extinction events, as well as claims for the environmental restriction of MISS, appear to result from sampling bias. In the second part of the paper we suggest that raised awareness of MISS has come at the cost of a decreasing appreciation of abiotic processes that may create morphologically similar features. By introducing the umbrella term ‘sedimentary surface textures’, of which MISS are one subset, we suggest a practical methodology for classifying such structures in the geological record. We illustrate how elucidating the formative mechanisms of ancient sedimentary surface textures usually requires consideration of a suite of sedimentological evidence from surrounding strata. Resultant interpretations, microbial or non-microbial, should be couched within a reasonable degree of uncertainty. This approach recognizes that morphological similarity alone does not constitute scientific proof of a common origin, and reinstates a passive descriptive terminology for sedimentary surface textures that cannot be achieved with the current MISS lexicon. It is hoped that this new terminology will reduce the number of overly sensational and misleading claims of MISS occurrence, and permit the means to practically separate initial observation from interpretation. Furthermore, this methodology offers a scientific approach that appreciates the low likelihood of conclusively identifying microbial structures from visual appearance alone, informing the search for true MISS in Earth's geological record and potentially on other planetary bodies such as Mars.Instances of sedimentary surface textures in the field were identified coincidentally during multiple seasons of varied field investigations primarily funded for NSD by a variety of organisations including a George Frederic Matthew Research Grant from the New Brunswick Museum for 2012, and a Discovery Grant from the Natural Sciences and Engineering Research Council of Canada to MRG. AGL is supported by the Natural Environment Research Council [grant number NE/L011409/1].This is the final version of the article. It first appeared from Elsevier via http://dx.doi.org/10.1016/j.earscirev.2016.01.00

Reasoning about topological and cardinal direction relations between 2-dimensional spatial objects

Increasing the expressiveness of qualitative spatial calculi is an essential step towards meeting the requirements of applications. This can be achieved by combining existing calculi in a way that we can express spatial information using relations from multiple calculi. The great challenge is to develop reasoning algorithms that are correct and complete when reasoning over the combined information. Previous work has mainly studied cases where the interaction between the combined calculi was small, or where one of the two calculi was very simple. In this paper we tackle the important combination of topological and directional information for extended spatial objects. We combine some of the best known calculi in qualitative spatial reasoning, the RCC8 algebra for representing topological information, and the Rectangle Algebra (RA) and the Cardinal Direction Calculus (CDC) for directional information. We consider two different interpretations of the RCC8 algebra, one uses a weak connectedness relation, the other uses a strong connectedness relation. In both interpretations, we show that reasoning with topological and directional information is decidable and remains in NP. Our computational complexity results unveil the significant differences between RA and CDC, and that between weak and strong RCC8 models. Take the combination of basic RCC8 and basic CDC constraints as an example: we show that the consistency problem is in P only when we use the strong RCC8 algebra and explicitly know the corresponding basic RA constraints

A reassessment of the problematic Ediacaran genus Orbisiana Sokolov 1976

The genus Orbisiana was established in 1976 by B.S. Sokolov based on a collection of seven specimens within core material from a borehole drilled through the Ediacaran-age Gavrilov Yam Formation of the Moscow Basin, Russia. Here we reassess the original material for the type species Orbisiana simplexSokolov 1976, which was long considered to be lost; fix the holotype of the type species; and revise the original diagnosis of the genus and species. Pyritisation of the fossils, which are preserved in finely laminated shales, allows three-dimensional morphological characterisation of this taxon using X-ray microtomography (μCT). Morphological and taphonomic analyses of the type material and additional three-dimensionally preserved specimens from the Verkhovka Formation (Vendian of the White Sea area) suggest that Orbisiana simplex consisted of submillimetric to millimetric globular chambers arranged in compact, grape-like clusters, or forming sinuous to linear aggregates. Occasionally, aggregates can bifurcate, with no appreciable change in chamber dimensions or shape. The phylogenetic affinity of Orbisiana remains uncertain, but its chambered construction, putative agglutinated structure of the chamber walls, and compact, occasionally branching chamber arrangement are shared with agglutinated tests of the Ediacaran genus Palaeopascichnus. Our reassessment and systematic study of the genus Orbisiana sheds new light on one of the least studied members of the late Ediacaran macroscopic biota.NER

EDIACARAN LIFE CLOSE to LAND: COASTAL and SHOREFACE HABITATS of the EDIACARAN MACROBIOTA, the CENTRAL FLINDERS RANGES, SOUTH AUSTRALIA

ABSTRACTThe Rawnsley Quartzite of South Australia hosts some of the world's most diverse Ediacaran macrofossil assemblages, with many of the constituent taxa interpreted as early representatives of metazoan clades. Globally, a link has been recognized between the taxonomic composition of individual Ediacaran bedding-plane assemblages and specific sedimentary facies. Thorough characterization of fossil-bearing facies is thus of fundamental importance for reconstructing the precise environments and ecosystems in which early animals thrived and radiated, and distinguishing between environmental and evolutionary controls on taxon distribution. This study refines the paleoenvironmental interpretations of the Rawnsley Quartzite (Ediacara Member and upper Rawnsley Quartzite). Our analysis suggests that previously inferred water depths for fossil-bearing facies are overestimations. In the central regions of the outcrop belt, rather than shelf and submarine canyon environments below maximum (storm-weather) wave base, and offshore environments between effective (fair-weather) and maximum wave base, the succession is interpreted to reflect the vertical superposition and lateral juxtaposition of unfossiliferous non-marine environments with fossil-bearing coastal and shoreface settings. Facies comprise: 1, 2) amalgamated channelized and cross-bedded sandstone (major and minor tidally influenced river and estuarine channels, respectively), 3) ripple cross-laminated heterolithic sandstone (intertidal mixed-flat), 4) silty-sandstone (possible lagoon), 5) planar-stratified sandstone (lower shoreface), 6) oscillation-ripple facies (middle shoreface), 7) multi-directed trough- and planar-cross-stratified sandstone (upper shoreface), 8) ripple cross-laminated, planar-stratified rippled sandstone (foreshore), 9) adhered sandstone (backshore), and 10) planar-stratified and cross-stratified sandstone with ripple cross-lamination (distributary channels). Surface trace fossils in the foreshore facies represent the earliest known evidence of mobile organisms in intermittently emergent environments. All facies containing fossils of the Ediacaran macrobiota remain definitively marine. Our revised shoreface and coastal framework creates greater overlap between this classic “White Sea” biotic assemblage and those of younger, relatively depauperate “Nama”-type biotic assemblages located in Namibia. Such overlap lends support to the possibility that the apparent biotic turnover between these assemblages may reflect a genuine evolutionary signal, rather than the environmental exclusion of particular taxa.NERC ERC Dr Schürmann Foundatio

Framboidal pyrite shroud confirms the ‘death mask’ model for moldic preservation of Ediacaran soft-bodied organisms—a reply

Thin, laterally extensive veneers of framboidal pyrite on fossiliferous bedding planes in eastern Newfoundland, Canada, provide evidence for post-burial microbially mediated pyritization of the seafloor in the late Ediacaran Period (Liu 2016). Pyrite is inferred to have formed on the external surfaces of soft-bodied organisms and microbial matgrounds as a result of bacterial sulfate reduction, consistent with the ‘death mask' taphonomic model for Ediacaran moldic preservation (Gehling 1999). Retallack (2017) accepts the evidence presented by Liu (2016) for early diagenetic pyritization of bedding planes in Newfoundland, and seems to offer at least tacit acceptance of evidence for modern oxidation of that pyrite, its widespread occurrence in global Ediacaran localities, and the potential influence of sedimentary pyrite burial on global Ediacaran oxygen concentrations. However, Retallack questions whether the presence of such pyrite veneers can be taken to demonstrate the ‘death mask' taphonomic model, and specifically queries the source of the observed pyrite

On the inverse Compton scattering model of radio pulsars

Some characteristics of the inverse Compton scattering (ICS) model are reviewed. At least the following properties of radio pulsars can be reproduced in the model: core or central emission beam, one or two hollow emission cones, different emission heights of these components, diverse pulse profiles at various frequencies, linear and circular polarization features of core and cones.Comment: 5 pages, no figures, LaTeX, a proceeding paper for Pacific Rim Conference on Stellar Astrophysics, Aug. 1999, HongKong, Chin