2,814 research outputs found
Pitfall Trap Collections of Ground Beetle Larvae (Coleoptera: Carabidae) in Kentucky Alfalfa Fields
Pitfall traps were installed in alfalfa fields to monitor the seasonality and abundance of immature ground beetles. Head capsule widths were determined by instar for Evarthrus sodalis, Harpalus pennsylvanicus, Chlaenius tricolor, Scarites subterraneus, Amara cupreolata, and A. impuncticollis. Seasonality of larval and adult catches indicated that E. sodalis, H. pennsylvanicus and A. impuncticollis overwinter in a larval diapause while A. cupreolata and S. subterraneus overwinter in the adult stage
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Exploring the role of line managers in developing and maintaining employee engagement levels
Account Management in Proof of Stake Ledgers
Blockchain protocols based on Proof-of-Stake (PoS) depend â by nature â on the active participation of stakeholders. If users are offline and abstain from the PoS consensus mechanism, the systemâs security is at risk, so it is imperative to explore ways to both maximize the level of participation and minimize the effects of non-participation. One such option is stake representation, such that users can delegate their participation rights and, in the process, form stake pools . The core idea is that stake pool operators always participate on behalf of regular users, while the users retain the ownership of their assets. Our work provides a formal PoS wallet construction that enables delegation and stake pool formation. While investigating the construction of addresses in this setting, we distil and explore address malleability, a security property that captures the ability of an attacker to manipulate the delegation information associated with an address. Our analysis consists of identifying multiple levels of malleability, which are taken into account in our paperâs core result. We then introduce the first ideal functionality of a PoS walletâs core which captures the PoS walletâs capabilities and is realized as a secure protocol based on standard cryptographic primitives. Finally, we cover how to use the wallet core in conjunction with a PoS ledger, as well as investigate how delegation and stake pools affect a PoS systemâs security
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Employee engagement in practice: examining the implementation of iMatter
Decontamination of a \u3cem\u3eHistoplasma capsulatum\u3c/em\u3e-Infested Blackbird Roost: Use of a Sprinkler System to Apply Formalin
When disturbed, blackbird/starling roost sites can be sources of locally severe outbreaks of histoplasmosis; therefore decontamination with formalin is sometimes prudent. We describe the use of a 17,000 with sprinkler system provided at no charge
Secret-Sharing for NP
A computational secret-sharing scheme is a method that enables a dealer, that
has a secret, to distribute this secret among a set of parties such that a
"qualified" subset of parties can efficiently reconstruct the secret while any
"unqualified" subset of parties cannot efficiently learn anything about the
secret. The collection of "qualified" subsets is defined by a Boolean function.
It has been a major open problem to understand which (monotone) functions can
be realized by a computational secret-sharing schemes. Yao suggested a method
for secret-sharing for any function that has a polynomial-size monotone circuit
(a class which is strictly smaller than the class of monotone functions in P).
Around 1990 Rudich raised the possibility of obtaining secret-sharing for all
monotone functions in NP: In order to reconstruct the secret a set of parties
must be "qualified" and provide a witness attesting to this fact.
Recently, Garg et al. (STOC 2013) put forward the concept of witness
encryption, where the goal is to encrypt a message relative to a statement "x
in L" for a language L in NP such that anyone holding a witness to the
statement can decrypt the message, however, if x is not in L, then it is
computationally hard to decrypt. Garg et al. showed how to construct several
cryptographic primitives from witness encryption and gave a candidate
construction.
One can show that computational secret-sharing implies witness encryption for
the same language. Our main result is the converse: we give a construction of a
computational secret-sharing scheme for any monotone function in NP assuming
witness encryption for NP and one-way functions. As a consequence we get a
completeness theorem for secret-sharing: computational secret-sharing scheme
for any single monotone NP-complete function implies a computational
secret-sharing scheme for every monotone function in NP
Proof-of-work sidechains
During the last decade, the blockchain space has exploded with a plethora of new cryptocurrencies, covering a wide array of different features, performance and security characteristics. Nevertheless, each of these coins functions in a stand-alone manner, independently. Sidechains have been envisioned as a mechanism to allow blockchains to communicate with one another and, among other applications, allow the transfer of value from one chain to another, but so far there have been no decentralized constructions. In this paper, we put forth the first side chains construction that allows communication between proof-of-work blockchains without trusted intermediaries. Our construction is generic in that it allows the passing of any information between blockchains. Using this construction, two blockchains can be connected in a âtwo-way pegâ in which an asset can be transferred from one chain to another and back. We pinpoint the features needed for two chains to communicate: On the source side, a proof-of-work blockchain that has been interlinked, potentially with a velvet fork; on the destination side, a blockchain with smart contract support. We put forth the smart contracts needed to implement these sidechains and explain them in detail. In the heart of our construction, we use a recently introduced cryptographic primitive, Non-Interactive Proofs of Proof-of-Work (NIPoPoWs)
Four-Round Concurrent Non-Malleable Commitments from One-Way Functions
How many rounds and which assumptions are required for concurrent non-malleable commitments? The above question has puzzled researchers for several years. Pass in [TCC 2013] showed a lower bound of 3 rounds for the case of black-box reductions to falsifiable hardness assumptions with respect to polynomial-time adversaries. On the other side, Goyal [STOC 2011], Lin and Pass [STOC 2011] and Goyal et al. [FOCS 2012] showed that one-way functions (OWFs) are sufficient with a constant number of rounds. More recently Ciampi et al. [CRYPTO 2016] showed a 3-round construction based on subexponentially strong one-way permutations. In this work we show as main result the first 4-round concurrent non-malleable commitment scheme assuming the existence of any one-way function. Our approach builds on a new security notion for argument systems against man-in-the-middle attacks: Simulation-Witness-Independence. We show how to construct a 4-round one-many simulation-witnesses-independent argument system from one-way functions. We then combine this new tool in parallel with a weak form of non-malleable commitments constructed by Goyal et al. in [FOCS 2014] obtaining the main result of our work
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A coalesced framework for prescribed and actual involvement of line managers in talent management (TM) analysis
Purpose: The mainstream literature presents the involvement of line managers (LMs) in Talent Management (TM) as a multi-dimensional concept that includes, among other things, the prescribed and actual dimensions of involvement, the analysis of which would best be supported by a unified framework. However, the literature shows a lack of unified framework for analysing the varied dimensions of involvement as the existing ones are fragmented. The paper aims to inductively generate a unified framework for analysing the prescribed and actual involvement of LMs in TM in the Case Study Organisation (CSO).
Design/Methodology/Approach: We adopted an inductive, qualitative and embedded singe case study. Semi-structured interviews were conducted with forty-seven (47) key stakeholders at different levels of the CSO alongside document analysis.
Findings: The study generated a coalesced framework that combines Cascon-Pereira and Valverde (2014) Four-dimensional framework (FDF), Teague and Roche (2012) Three-dimensional framework (TDF), and institutional isomorphism concept (DiMaggio and Powell 1983) for analysing the prescribed and actual involvement of LMs in TM in CSO.
Limitation: The results are limited to the CSO as this was a single case study.
Originality/value: The study extends the boundaries of using FDF, TDF and institutional isomorphism concept (DiMaggio and Powell 1983) by merging them into a coalesced framework to analyse the prescribed and actual involvement of LMs in TM in CSO. Thus, the framework bridges the gap between theory and practice within the TM domain
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