2,418 research outputs found

    Innovation, Adoption, Ownership, and Productivity: Evidence from Ukraine

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    How do new and foreign firms achieve superior productivity? Do they conduct more and better R&D? Or do they distinguish themselves through computerization and organizational capital? We investigate the determinants of and returns to several types of investment, using a panel of over 40,000 Ukrainian industrial firms in 2000-2007. Foreign firms engage in more non-technological investment and IT and less in R&D than domestic private firms. Similarly, new firms invest more in non-technological capital and IT and less in R&D than initially state-owned firms. Productivity gains from R&D and non-technology investment are insignificantly different across ownership types, whereas foreign firms achieve much higher returns to IT investment than other firms. These results suggest that foreign firms outperform others via organizational capital that is better able to exploit IT investment. New firm productivity growth is a result of higher investment volume rather than investment efficiency.R&D, information technology, foreign ownership, transition, Eastern Europe, Ukraine

    Contributions to an arthropod inventory of Santa Cruz Island, California

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    Arthropods have been understudied on Santa Cruz Island, resulting in an incomplete understanding of these diverse and ecologically important members of island ecosystems. To enhance the current understanding of Santa Cruz Island biodiversity, we sampled arthropods in 2 native plant habitats: island scrub oak (Quercus pacifica) woodland and patches of island morning glory (Calystegia macrostegia ssp. macrostegia). We used 4 standardized sampling techniques to sample arthropods in 16 Q. pacifica woodland plots. We sampled arthropods associated with C. macrostegia by pan trapping within 1 m of blooming morning glory individuals. In total, we sampled over 18,000 arthropod specimens, sorted the specimens to morphotypes by order, and had taxonomic specialists identify 10 orders to the narrowest possible identification (n = 458 total species or morphotypes). The taxonomic distribution of our identified specimens is as follows: 1 species of Scorpiones, 5 morphospecies of Pseudoscorpiones, 74 species of Araneae, 4 species of Orthoptera, 10 species of Psocodea, 10 species of Hemiptera, 1 species of Neuroptera, 60 species of Coleoptera, 8 species of Lepidoptera, and 42 species of Hymenoptera (Formicidae and Apoidea). Of these, 62 species represent newly recorded arthropod species on Santa Cruz Island. The diversity of our collections within the Quercus pacifica and Calystegia macrostegia habitats, the deficiency of current knowledge of Channel Island arthropods, and the fundamental role of arthropods in island ecosystems emphasize the need for a more comprehensive arthropod inventory across the California Channel Islands

    Parameterized Model-Checking for Timed-Systems with Conjunctive Guards (Extended Version)

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    In this work we extend the Emerson and Kahlon's cutoff theorems for process skeletons with conjunctive guards to Parameterized Networks of Timed Automata, i.e. systems obtained by an \emph{apriori} unknown number of Timed Automata instantiated from a finite set U1,
,UnU_1, \dots, U_n of Timed Automata templates. In this way we aim at giving a tool to universally verify software systems where an unknown number of software components (i.e. processes) interact with continuous time temporal constraints. It is often the case, indeed, that distributed algorithms show an heterogeneous nature, combining dynamic aspects with real-time aspects. In the paper we will also show how to model check a protocol that uses special variables storing identifiers of the participating processes (i.e. PIDs) in Timed Automata with conjunctive guards. This is non-trivial, since solutions to the parameterized verification problem often relies on the processes to be symmetric, i.e. indistinguishable. On the other side, many popular distributed algorithms make use of PIDs and thus cannot directly apply those solutions

    Mucosal Vaccination with a Self-Adjuvanted Lipopeptide Is Immunogenic and Protective against Mycobacterium tuberculosis

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    Tuberculosis (TB) remains a staggering burden on global public health. Novel preventative tools are desperately needed to reach the targets of the WHO post-2015 End-TB Strategy. Peptide or protein-based subunit vaccines offer potential as safe and effective generators of protection, and enhancement of local pulmonary immunity may be achieved by mucosal delivery. We describe the synthesis of a novel subunit vaccine via native chemical ligation. Two immunogenic epitopes, ESAT61−20 and TB10.43−11 from Mycobacterium tuberculosis (Mtb), were covalently conjugated to the TLR2-ligand Pam2Cys to generate a self-adjuvanting lipopeptide vaccine. When administered mucosally to mice, the vaccine enhanced pulmonary immunogenicity, inducing strong Th17 responses in the lungs and multifunctional peripheral T-lymphocytes. Mucosal, but not peripheral vaccination, provided substantial protection against Mtb infection, emphasizing the importance of delivery route for optimal efficacy.NHMR

    The targeted delivery of multicomponent cargos to cancer cells by nanoporous particle-supported lipid bilayers.

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    Encapsulation of drugs within nanocarriers that selectively target malignant cells promises to mitigate side effects of conventional chemotherapy and to enable delivery of the unique drug combinations needed for personalized medicine. To realize this potential, however, targeted nanocarriers must simultaneously overcome multiple challenges, including specificity, stability and a high capacity for disparate cargos. Here we report porous nanoparticle-supported lipid bilayers (protocells) that synergistically combine properties of liposomes and nanoporous particles. Protocells modified with a targeting peptide that binds to human hepatocellular carcinoma exhibit a 10,000-fold greater affinity for human hepatocellular carcinoma than for hepatocytes, endothelial cells or immune cells. Furthermore, protocells can be loaded with combinations of therapeutic (drugs, small interfering RNA and toxins) and diagnostic (quantum dots) agents and modified to promote endosomal escape and nuclear accumulation of selected cargos. The enormous capacity of the high-surface-area nanoporous core combined with the enhanced targeting efficacy enabled by the fluid supported lipid bilayer enable a single protocell loaded with a drug cocktail to kill a drug-resistant human hepatocellular carcinoma cell, representing a 10(6)-fold improvement over comparable liposomes

    Immunoglobulin variable-region gene mutational lineage tree analysis: application to autoimmune diseases

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    Lineage trees have frequently been drawn to illustrate diversification, via somatic hypermutation (SHM), of immunoglobulin variable-region (IGV) genes. In order to extract more information from IGV sequences, we developed a novel mathematical method for analyzing the graphical properties of IgV gene lineage trees, allowing quantification of the differences between the dynamics of SHM and antigen-driven selection in different lymphoid tissues, species, and disease situations. Here, we investigated trees generated from published IGV sequence data from B cell clones participating in autoimmune responses in patients with Myasthenia Gravis (MG), Rheumatoid Arthritis (RA), and Sjögren's Syndrome (SS). At present, as no standards exist for cell sampling and sequence extraction methods, data obtained by different research groups from two studies of the same disease often vary considerably. Nevertheless, based on comparisons of data groups within individual studies, we show here that lineage trees from different individual patients are often similar and can be grouped together, as can trees from two different tissues in the same patient, and even from IgG- and IgA-expressing B cell clones. Additionally, lineage trees from most studies reflect the chronic character of autoimmune diseases

    Some strategic national initiatives for the Swedish education in the geodata field

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    Ponencias, comunicaciones y pĂłsters presentados en el 17th AGILE Conference on Geographic Information Science "Connecting a Digital Europe through Location and Place", celebrado en la Universitat Jaume I del 3 al 6 de junio de 2014.This paper describes national cooperation in Sweden launched by its universities and authorities, aimed at improving geodata education. These initiatives have been focused upon providing common access to geodata, the production of teaching materials in Swedish and organizing annual meetings for teachers. We argue that this type of cooperation is vital to providing high quality education for a poorly recognized subject in a country with a relatively small population

    Actin dynamics tune the integrated stress response by regulating eukaryotic initiation factor 2α dephosphorylation.

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    Four stress-sensing kinases phosphorylate the alpha subunit of eukaryotic translation initiation factor 2 (eIF2α) to activate the integrated stress response (ISR). In animals, the ISR is antagonised by selective eIF2α phosphatases comprising a catalytic protein phosphatase 1 (PP1) subunit in complex with a PPP1R15-type regulatory subunit. An unbiased search for additional conserved components of the PPP1R15-PP1 phosphatase identified monomeric G-actin. Like PP1, G-actin associated with the functional core of PPP1R15 family members and G-actin depletion, by the marine toxin jasplakinolide, destabilised the endogenous PPP1R15A-PP1 complex. The abundance of the ternary PPP1R15-PP1-G-actin complex was responsive to global changes in the polymeric status of actin, as was its eIF2α-directed phosphatase activity, while localised G-actin depletion at sites enriched for PPP1R15 enhanced eIF2α phosphorylation and the downstream ISR. G-actin's role as a stabilizer of the PPP1R15-containing holophosphatase provides a mechanism for integrating signals regulating actin dynamics with stresses that trigger the ISR.This work was funded by the Medical Research Council (UK) (MRC Ref G1002610) and a Wellcome Trust Strategic Award for core facilities to the Cambridge Institute for Medical Research (CIMR, Wellcome 100140). SJM holds a Senior Clinical Research Fellowship from the Medical Research Council (MRC Ref G1002610). DR is a Wellcome Trust Principal Research Fellow (Wellcome 084812/Z/08/Z). The June Hancock Mesothelioma Research Fund funded LED (JH09-2); the British Lung Foundation funded HJC (APHD11-4); CD is a member of the CIMR PhD programme funded by the Wellcome Trust; and VP holds a Diabetes UK Arthur and Sadie Pethybridge PhD Studentship.This is the final published version. It first appeared at http://elifesciences.org/content/4/e04872
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