4,812 research outputs found
Interspecific differences in the larval performance of Pieris butterflies (Lepidoptera: Pieridae) are associated with differences in the glucosinolate profiles of host plants
The tremendous diversity of plants and herbivores has arisen from a coevolutionary relationship characterized by plant defense and herbivore counter adaptation. Pierid butterfly species feed on Brassicales plants that produce glucosinolates as a chemical deterrent against herbivory. In turn, the larvae of pierids have nitrile specifier proteins (NSPs) that are expressed in their gut and disarm glucosinolates. Pierid butterflies are known to have diversified in response to glucosinolate diversification in Brassicales. Therefore, each pierid species is expected to have a spectrum of host plants characterized by specific glucosinolate profiles. In this study, we tested whether the larval performance of different Pieris species, a genus in Pieridae (Lepidoptera: Pieridae), was associated with plant defense traits of putative host plants. We conducted feeding assays using larvae of three Pieris species and 10 species of the Brassicaceae family possessing different leaf physical traits and glucosinolate profile measurements. The larvae of Pieris rapae responded differently in the feeding assays compared with the other two Pieris species. This difference was associated with differences in glucosinolate profiles but not with variations in physical traits of the host plants. This result suggests that individual Pieris species are adapted to a subset of glucosinolate profiles within the Brassicaceae. Our results support the idea that the host ranges of Pieris species depend on larval responses to glucosinolate diversification in the host species, supporting the hypothesis of coevolution between butterflies and host plants mediated by the chemical arms race
Room temperature ferromagnetic behavior in the hollandite-type titanium oxide
A hollandite-type K(x)Ti(8)O(16) polycrystalline sample has been prepared and studied by magnetization, resistivity and x-ray photoelectron spectroscopy (XPS). Room temperature ferromagnetic behavior is observed in the magnetic hysteresis measurement. The sample shows a semiconductive temperature dependence in the resistivity measurement. Analysis of the Ti 2p(3/2) core-level XPS spectrum indicates that the titanium ions have a mixed valence of Ti(4+) and Ti(3+). In addition, the valence band spectrum reveals that the 3d electrons tend to localize on Ti(3+) ions in the hollandite-type TiO(2) lattice. Also, analysis of the valence band spectrum shows that the prepared sample is a wide-gap oxide with a band gap of 3.6 eV. These results indicate that the present hollandite-type K(x)Ti(8)O(16) sample can be classified as a TiO(2)-based wide-gap semiconductor with Curie temperature above room temperature. Room temperature ferromagnetism (RTFM) decreases in the sample prepared under a strong reducing gas atmosphere, accompanied with the decrease in the resistivity. The results imply that the localized 3d electrons are responsible for the RTFM of the K(x)Ti(8)O(16) sample
Hybrid ECAL: Optimization and Related Developments
Hybrid ECAL is a cost-conscious option of electromagnetic calorimeter (ECAL)
for particle flow calorimetry to be used in a detector of International Linear
Collider (ILC). It is a combination of silicon-tungsten ECAL, which realizes
high granularity and robust measurement of electromagnetic shower, and
scintillator-tungsten ECAL, which gives affordable cost with similar
performance to silicon. Optimization and a data acquisition trial in a test
bench for the hybrid ECAL are described in this article.Comment: 7 pages, 4 figures, Talk presented at the International Workshop on
Future Linear Colliders (LCWS14), Belgrade, Serbia, 6-10 October 201
A Semantic Framework for the Security Analysis of Ethereum smart contracts
Smart contracts are programs running on cryptocurrency (e.g., Ethereum)
blockchains, whose popularity stem from the possibility to perform financial
transactions, such as payments and auctions, in a distributed environment
without need for any trusted third party. Given their financial nature, bugs or
vulnerabilities in these programs may lead to catastrophic consequences, as
witnessed by recent attacks. Unfortunately, programming smart contracts is a
delicate task that requires strong expertise: Ethereum smart contracts are
written in Solidity, a dedicated language resembling JavaScript, and shipped
over the blockchain in the EVM bytecode format. In order to rigorously verify
the security of smart contracts, it is of paramount importance to formalize
their semantics as well as the security properties of interest, in particular
at the level of the bytecode being executed.
In this paper, we present the first complete small-step semantics of EVM
bytecode, which we formalize in the F* proof assistant, obtaining executable
code that we successfully validate against the official Ethereum test suite.
Furthermore, we formally define for the first time a number of central security
properties for smart contracts, such as call integrity, atomicity, and
independence from miner controlled parameters. This formalization relies on a
combination of hyper- and safety properties. Along this work, we identified
various mistakes and imprecisions in existing semantics and verification tools
for Ethereum smart contracts, thereby demonstrating once more the importance of
rigorous semantic foundations for the design of security verification
techniques.Comment: The EAPLS Best Paper Award at ETAP
Music and Man in Art : The Future of Media and Technology
Music can provide psychological benefit, and music therapy has been accepted for many people across the world. Iso-principle has been known as an important concept in music therapy. Art is roughly divided into two categories, which are visual arts and reproducing arts. An attempt to overlap these categories would be a method of recording and playing back music. Historically, human could come to experience polyphonic music like the instrument of Carillon, to listen to reproducing music by music score and phonograph, and to be enjoy music anytime by use of media and technology. Recent music environment includes the voice synthesis technology "VOCALOID", a video distribution site on the internet. In the future, music will make people happier if new technologies are widely recognized and personalized use is widespread
Enrichment of Strontium in Dwarf Galaxies
Light trans-iron elements such as Sr serve as the key to understanding the astrophysical sites of heavy elements. Spectroscopic studies of metal-poor stars have revealed large star-to-star scatters in the ratios of [Sr/Ba], which indicates that there are multiple sites for the production of Sr. Here we present the enrichment history of Sr by a series of the -body/smoothed particle hydrodynamics simulations of a dwarf galaxy with a stellar mass of 3 10 . We show that binary neutron star mergers (NSMs) and asymptotic giant branch (AGB) stars contribute to the enrichment of Sr in the metallicity ranges [Fe/H] 3 and [Fe/H] 1, respectively. It appears insufficient, however, to explain the overall observational trends of Sr by considering only these sites. We find that the models including electron-capture supernovae (ECSNe) and rotating massive stars (RMSs), in addition to NSMs and AGBs, reasonably reproduce the enrichment histories of Sr in dwarf galaxies. The contributions of both ECSNe and NSMs make scatters of 0.2 dex in [Sr/Fe], [Sr/Ba], and [Sr/Zn] as can be seen for observed stars in the metallicity range [Fe/H] . We also find that the mass range of ECSN progenitors should be substantially smaller than (e.g., 0.1-) to avoid over-prediction of [Sr/Ba] and [Sr/Zn] ratios. Our results demonstrate that NSMs, AGBs, ECSNe, and RMSs all play roles in the enrichment histories of Local Group dwarf galaxies, although more observational data are required to disentangle the relative contributions of these sources
Designing Secure Ethereum Smart Contracts: A Finite State Machine Based Approach
The adoption of blockchain-based distributed computation platforms is growing
fast. Some of these platforms, such as Ethereum, provide support for
implementing smart contracts, which are envisioned to have novel applications
in a broad range of areas, including finance and Internet-of-Things. However, a
significant number of smart contracts deployed in practice suffer from security
vulnerabilities, which enable malicious users to steal assets from a contract
or to cause damage. Vulnerabilities present a serious issue since contracts may
handle financial assets of considerable value, and contract bugs are
non-fixable by design. To help developers create more secure smart contracts,
we introduce FSolidM, a framework rooted in rigorous semantics for designing
con- tracts as Finite State Machines (FSM). We present a tool for creating FSM
on an easy-to-use graphical interface and for automatically generating Ethereum
contracts. Further, we introduce a set of design patterns, which we implement
as plugins that developers can easily add to their contracts to enhance
security and functionality
Analysis of Reaction Forces and Posture of a Bunch of Crop Stalks During Reel Operations of a Combine Harvester
Rosana G. Moreira, Editor-in-Chief; Texas A&M UniversityThis is a Technical Paper from International Commission of Agricultural Engineering (CIGR, Commission Internationale du Genie Rural) E-Journal Volume 4 (2002): Y. Hirai, E. Inoue, K. Mori, and K. Hashiguchi. Analysis of Reaction Forces and Posture of a Bunch of Crop Stalks During Reel Operations of a Combine Harvester. Vol. IV. October 2002
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