24,835 research outputs found
Letter to the editor. Distribution of genomic breakpoints in chronic myeloid leukemia: analysis of 308 patients
Letter to the EditorD M Ross, M O'Hely, P A Bartley, P Dang, J Score, J M Goyne, M Sobrinho-Simoes, N C P Cross, J V Melo, T P Speed, T P Hughes, and A A Morle
Composition and distribution of the peracarid crustacean fauna along a latitudinal transect off Victoria Land (Ross Sea, Antarctica) with special emphasis on the Cumacea
The following study was the first to describe composition and structure of the peracarid fauna systematically along a latitudinal transect off Victoria Land (Ross Sea, Antarctica). During the 19th Antarctic expedition of the Italian research vessel “Italica” in February 2004, macrobenthic samples were collected by means of a Rauschert dredge with a mesh size of 500 m at depths between 85 and 515 m. The composition of peracarid crustaceans, especially Cumacea was investigated. Peracarida contributed 63% to the total abundance of the fauna. The peracarid samples were dominated by amphipods (66%), whereas cumaceans were represented with 7%. Previously, only 13 cumacean species were known, now the number of species recorded from the Ross Sea increased to 34. Thus, the cumacean fauna of the Ross Sea, which was regarded as the poorest in terms of species richness, has to be considered as equivalent to that of other high Antarctic areas. Most important cumacean families concerning abundance and species richness were Leuconidae, Nannastacidae, and Diastylidae. Cumacean diversity was lowest at the northernmost area (Cape Adare). At the area off Coulman Island, which is characterized by muddy sediment, diversity was highest. Diversity and species number were higher at the deeper stations and abundance increased with latitude. A review of the bathymetric distribution of the Cumacea from the Ross Sea reveals that most species distribute across the Antarctic continental shelf and slope. So far, only few deep-sea records justify the assumption of a shallow-water–deep-sea relationship in some species of Ross Sea Cumacea, which is discussed from an evolutionary point of view
Education Quality Matters:Trends and Challenges
British Computer Society INSPIRE conference proceedingseditors K Phalp. V Katos, S Meacham, M Ross, G Staples, J Uhomoibhi <br/
The Expanding Scope of Warrantless Automobile Searches: United States v. Ross
This Comment examines the justifications articulated by the Court in United States v. Ross for expanding the scope of warrantless searches under the automobile exception. The author argues that the stated rationales are not consistent with prior law and do not support the Court\u27s decision. The author also argues that the Court\u27s holding in Ross requires an abandonment of the expansion of warrantless searches under the search incident to arrest exception
RedDots: Limits on habitable and undetected planets orbiting nearby stars GJ 832, GJ 674, and Ross 128
Context . The nearby ( d < 5 pc) M dwarfs GJ 832, GJ 674, and Ross 128 each host a single exoplanet, with Ross 128 b located within the optimistic habitable zone. Due to their low mass and close proximity, these three systems are prime candidates for further characterization studies. Aims . Using HARPS spectroscopic data obtained by the RedDots campaign, as well as archival data from HARPS and CARMENES, supplemented with ASH2 and T90 photometry, we aim to search for additional planets in the three systems. We also aim to determine limits on possible undetected, habitable planets. We investigate (i) the reliability of the recovered orbital eccentricities and (ii) the reliability of Bayesian evidence as a diagnostic for selecting the best model. Methods . We employed Markov-chain Monte Carlo, nested sampling, and Gaussian process (GP) analyses to fit a total of 20 different models comprising 0–2 Keplerian signals and three different GP kernels for stellar activity. We used the residuals to create grids for injection-recovery simulations to obtain detection limits on potentially undiscovered planets. Results . Our refined orbital elements for GJ 832 b, GJ 674 b, and Ross 128 b confirm (GJ 832, GJ 674) or increase (Ross 128) prior eccentricity determinations. No additional planets were found in any of the systems. The detection limits obtained for all three systems are between 30 and 50 cm s −1 for orbital periods in the range of 1–10 000 days. This corresponds to habitable planet masses of <1.5 M ⊕ for GJ 832 and < 1 M ⊕ for GJ 674 and Ross 128. Using N-body simulations, we find that undiscovered secondary planets are unlikely (Ross 128) or incapable (GJ 674) of having caused the observed eccentricities of the known planets. We find that the eccentricity of GJ 832b is not significantly different from zero. Conclusions . GJ 832 b, GJ 674 b, and Ross 128 b retain their status as hosting lonely and (for the latter two) eccentric planets ( e = 0.04, 0.24, 0.21; respectively). This is unexpected in classical planet formation scenarios, which favor circular orbits and multiplanet configurations, demonstrating that planet formation in these cases is more complicated than traditionally thought. Additionally, the eccentricity of Ross 128 indicates that it spends some of its orbit outside of the optimistic habitable zone. Finally, our results show that Bayesian evidence, when used in conjunction with GP, is not a robust diagnostic for selecting the best model in cases of low- activity stars. In such cases, we advise an inspection of the shapes of the posterior distributions and to ensure that relevant simulations are performed to assess the validity of the perceived best model
Induction of programmed cell death in mammalian cells by isolates of Ross River virus
Arthritogenic alphaviruses, such as Ross River virus (RRV) are associated with worldwide outbreaks of human polyarthritis/arthralgia. The pathogenesis of RRV and other alphaviruses is poorly understood. Studies have shown potential links between the different strains of RRV and variation in their pathogenesis and virulence. Currently there is believed to be two circulating strains of RRV, the south western (SW) from the south west region of Western Australia and the north eastern (NE) from the east coast of Australia. Studies have suggested that the persistence of RRV may be the result of an impaired immune response. This study was designed to determine if the SW and NE isolates of RRV have the ability to induce apoptosis in DCs and fibroblasts and discover any possible variation in their apoptosis-inducing capacity. Both Vero cells and murine bone marrow DCs (BMDCs) were infected with the SW74249 (SW) and SW82627 (NE) strains of RRV. A time course analysis of two apoptotic markers and a cell viability marker for both cell types was conducted by flow cytometry. The results indicate RRV- induced apoptosis in both Vero cells and BMDCs, with RRV inducing a stronger pro-apoptotic response in BMDCs than Vero cells, 24 h after infection. Between the two strains there was little variation in the Vero cells over time. In the BMDCs there was some variation with the RRV-SW strain inducing a higher percentage of cell death than the RRV-NE strain, 24 h after infection. Collectively, the data indicates that RRV has the capacity to induce a pro-apoptotic response in DCs, with the SW presenting as more aggressive compared to the NE, potentially leading to greater virulence. This data could help to explain the mechanism of RRV persistence in vertebrate hosts, as well as the reported differences in severity and duration of human clinical symptoms. Immunotherapy aimed at correcting the patient’s dysfunctional immune system, may represent a new strategy for the successful medical treatment of RRV infection
Influence of hosts on the ecology of arboviral transmission: Potential mechanisms influencing dengue, Murray Valley encephalitis, and Ross River virus in Australia
Ecological interactions are fundamental to the transmission of infectious disease. Arboviruses are particularly elegant examples, where rich arrays of mechanisms influence transmission between vectors and hosts. Research on host contributions to the ecology of arboviral diseases has been undertaken within multiple subdisciplines, but significant gaps in knowledge remain and multidisciplinary approaches are needed. Through our multidisciplinary review of the literature we have identified five broad areas where hosts may influence the ecology of arboviral transmission: host immunity; cross-protective immunity and antibody-dependent enhancement; host abundance; host diversity; and pathogen spillover and dispersal. Herein we discuss the known and theoretical roles of hosts within these topics and then apply this knowledge to three epidemiologically important mosquito-borne arboviruses that occur in Australia: dengue virus (DENV), Murray Valley encephalitis virus (MVEV), and Ross River virus (RRV). We argue that the underlying mechanisms by which hosts influence arboviral activity are numerous and attempts to delineate these mechanisms further are needed. Investigations that focus on hosts of vector-borne diseases are likely to be rewarding, particularly where the ecology of vectors is relatively well understood. From an applied perspective, enhanced knowledge of host influences upon vector-borne disease transmission is likely to enable better management of disease burden. Finally, we suggest a framework that may be useful to identify and determine host contributions to the ecology of arboviruses
Holocene sea ice variability driven by wind and polynya efficiency in the Ross Sea
The causes of the recent increase in Antarctic sea ice extent, characterised by large regional contrasts and decadal variations, remain unclear. In the Ross Sea, where such a sea ice increase is reported, 50% of the sea ice is produced within wind-sustained latent-heat polynyas. Combining information from marine diatom records and sea salt sodium and water isotope ice core records, we here document contrasting patterns in sea ice variations between coastal and open sea areas in Western Ross Sea over the current interglacial period. Since about 3600 years before present, an increase in the efficiency of regional latent-heat polynyas resulted in more coastal sea ice, while sea ice extent decreased overall. These past changes coincide with remarkable optima or minima in the abundances of penguins, silverfish and seal remains, confirming the high sensitivity of marine ecosystems to environmental and especially coastal sea ice conditions. © 2017 The Author(s)
Programming languages and principles for read–write linked data
This work addresses a gap in the foundations of computer science. In particular, only a limited number of models address design decisions in modern Web architectures. The development of the modern Web architecture tends to be guided by the intuition of engineers. The intuition of an engineer is probably more powerful than any model; however, models are important tools to aid principled design decisions. No model is sufficiently strong to provide absolute certainty of correctness; however, an architecture accompanied by a model is stronger than an architecture accompanied solely by intuition lead by the personal, hence subjective, subliminal ego.The Web of Data describes an architecture characterised by key W3C standards. Key standards include a semi-structured data format, entailment mechanism and query language. Recently, prominent figures have drawn attention to the necessity of update languages for the Web of Data, coining the notion of Read–Write Linked Data. A dynamicWeb of Data with updates is a more realistic reflection of the Web.An established and versatile approach to modelling dynamic languages is to define an operational semantics. This work provides such an operational semantics for a Read–Write Linked Data architecture. Furthermore, the model is sufficiently general to capture the established standards, including queries and entailments. Each feature is relative easily modelled in isolation; however a model which checks that the key standards socialise is a greater challenge to which operational semantics are suited. The model validates most features of the standards while raising some serious questions.Further to evaluating W3C standards, the operational mantics provides a foundation for static analysis. One approach is to derive an algebra for the model. The algebra is proven to be sound with respect to the operational semantics. Soundness ensures that the algebraic rules preserve operational behaviour. If the algebra establishes that two updates are equivalent, then they have the same operational capabilities. This is useful for optimisation, since the real cost of executing the updates may differ, despite their equivalent expressive powers. A notion of operational refinement is discussed, which allows a non-deterministic update to be refined to a more deterministic update.Another approach to the static analysis of Read–Write Linked Data is through a type system. The simplest type system for this application simply checks that well understood terms which appear in the semi-structured data, such as numbers and strings of characters, are used correctly. Static analysis then verifies that basic runtime errors in a well typed program do not occur. Type systems for URIs are also investigated, inspired by W3C standards. Type systems for URIs are controversial, since URIs have no internal structure thus have no obvious non-trivial types. Thus a flexible type system which accommodates several approaches to typing URIs is proposed
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