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While the size and complexity of software are rapidly increasing, not only is the number of vulnerabilities increasing, but their forms are diversifying. Vulnerability has become an important factor in network attack and defense. Therefore, automatic vulnerability discovery has become critical to ensure software security. Fuzzing is one of the most important methods of vulnerability discovery. It is based on the initial input, i.e., a seed, to generate mutated test cases as new inputs of a tested program in the next execution loop. By monitoring the path coverage, fuzzing can choose high-value test cases for inclusion in the new seed set and capture crashes used for triggering vulnerabilities. Although there have been remarkable achievements in terms of the number of discovered vulnerabilities, the reduction of time cost is still inadequate. This paper proposes a fast directed greybox fuzzing model, FastAFLGo. A fast convergence formula of temperature is designed, and the energy scheduling scheme can quickly determine the best seed to make the program execute toward the target basic blocks. Experimental results show thatFastAFLGo can discover more vulnerabilities than the traditional fuzzing method in the same execution time. [ABSTRACT FROM AUTHOR]

The concept of a tolerance relation, shortly called tolerance, was studied on various algebras since the seventies of the twentieth century by B. Zelinka and the first author (see e.g. [6] and the monograph [1] and the references therein). Since tolerances need not be transitive, their blocks may overlap and hence in general the set of all blocks of a tolerance cannot be converted into a quotient algebra in the same way as in the case of congruences. However, G. Czédli ([7]) showed that lattices can be factorized by means of tolerances in a natural way, and J. Grygiel and S. Radeleczki ([8]) proved some variant of an Isomorphism Theorem for tolerances on lattices. The aim of the present paper is to extend the concept of a tolerance on a lattice to posets in such a way that results similar to those obtained for tolerances on lattices can be derived. [ABSTRACT FROM AUTHOR]

In organ transplantation, there is a lack of ethical discussion about the recipient's right not to receive a transplant. Using the current situation of living organ transplantation and deceased organ transplantation in Japan as an example, we prospectively discussed to what extent the recipient's right not to receive a transplant is ethically acceptable. In directed transplantation from a living donor, a recipient may refuse organ donation from a particular donor. It is preferable that a recipient's request for organ donation from a donor occurs as part of a transparent process. In nondirected transplantation from a deceased donor, refusal of transplantation from a particular type of donor appears potentially justifiable. There are both moral and pragmatic considerations. Certain refusals based solely on belief are morally unacceptable, and refusal to transplant a recipient based on the donor's age jeopardizes the entire transplant system. When religious beliefs affect mental and physical health, individualized measures are required for transplant rejection. We also deductively developed a prospective argument based on the current status of donor–recipient communication in living organ transplantation in Japan and the 2010 amendment of the law allowing relatives to be given priority in organ transplantation from deceased donors. [ABSTRACT FROM AUTHOR]

In this paper, the state controllability of networked higher-dimensional linear time-invariant dynamical systems is considered, where communications are performed through one-dimensional connections. The influences on the controllability of such a networked system are investigated, which come from a combination of network topology, node-system dynamics, external control inputs and inner interactions. Particularly, necessary and sufficient conditions are presented for the controllability of the network with a general topology, as well as for some special settings such as cycles and chains, which show that the observability of the node system is necessary in general and the controllability of the node system is necessary for chains but not necessary for cycles. Moreover, two examples are constructed to illustrate that uncontrollable node systems can be assembled to a controllable networked system, while controllable node systems may lead to uncontrollable systems even for the cycle topology. This article is part of the themed issue ‘Horizons of cybernetical physics’. [ABSTRACT FROM AUTHOR]

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Information is often described as a reduction of uncertainty associated with a restriction of possible choices. Despite appearing in Hartley's foundational work on information theory, there is a surprising lack of a formal treatment of this interpretation in terms of exclusions. This paper addresses the gap by providing an explicit characterisation of information in terms of probability mass exclusions. It then demonstrates that different exclusions can yield the same amount of information and discusses the insight this provides about how information is shared amongst random variables—lack of progress in this area is a key barrier preventing us from understanding how information is distributed in complex systems. The paper closes by deriving a decomposition of the mutual information which can distinguish between differing exclusions; this provides surprising insight into the nature of directed information. [ABSTRACT FROM AUTHOR]

Information is often described as a reduction of uncertainty associated with a restriction of possible choices. Despite appearing in Hartley’s foundational work on information theory, there is a surprising lack of a formal treatment of this interpretation in terms of exclusions. This paper addresses the gap by providing an explicit characterisation of information in terms of probability mass exclusions. It then demonstrates that different exclusions can yield the same amount of information and discusses the insight this provides about how information is shared amongst random variables—lack of progress in this area is a key barrier preventing us from understanding how information is distributed in complex systems. The paper closes by deriving a decomposition of the mutual information which can distinguish between differing exclusions; this provides surprising insight into the nature of directed information.

Background: The dichotic digits test is one of the most widely used assessment tools for central auditory processing disorder. However, questions remain concerning the impact of cognitive factors on test results. Purpose: To develop the Dichotic Digits difference Test (DDdT), an assessment tool that could differentiate children with cognitive deficits from children with genuine dichotic deficits based on differential test results. The DDdT consists of four subtests: dichotic free recall (FR), dichotic directed left ear (DLE), dichotic directed right ear (DRE), and diotic. Scores for six conditions are calculated (FR left ear [LE], FR right ear [RE], and FR total, as well as DLE, DRE, and diotic). Scores for four difference measures are also calculated: dichotic advantage, right-ear advantage (REA) FR, REA directed, and attention advantage. Research Design: Experiment 1 involved development of the DDdT, including error rate analysis. Experiment 2 involved collection of normative and test-retest reliability data. Study Sample: Twenty adults (aged 25 yr 10 mo to 50 yr 7 mo, mean 36 yr 4 mo) took part in the development study; 62 normal-hearing, typically developing, primary-school children (aged 7 yr 1 mo to 11 yr 11 mo, mean 9 yr 4 mo) and 10 adults (aged 25 yr 0 mo to 51 yr 6 mo, mean 34 yr 10 mo) took part in the normative and test-retest reliability study. Data Collection and Analysis: In Experiment 1, error rate analysis was conducted on the 36 digit-pair combinations of the DDdT. Normative data collected in Experiment 2 were arcsine transformed to achieve a distribution that was closer to a normal distribution and z-scores calculated. Pearson product-moment correlations were used to determine the strength of relationships between DDdT conditions. Results: The development study revealed no significant differences in the adult population between test and retestonany DDdT condition. Error rates on 36 digit pairs ranged from 1.5% to 16.7%. The most and the least error-prone digits were removed before commencement of the normative data study, leaving 25 unique digit pairs. Average z-scores calculated from the arcsine-transformed data collected from the 62 children who took part in the normative data study revealed that FR dichotic processing (LE, RE, and total) was highly correlated with diotic processing (/"ranging from 0.5 to 0.6; p < 0.0001). Significant improvements in performance on retest occurred for the FR LE, RE, total, and diotic conditions (p ranging from 0.05 to 0.0004), the conditions that would be expected to improve with practice if the participant's response strategies are better the second time around. Conclusions: The addition of a diotic control task--that shares many response demands with the usual dichotic tasks--opens up the possibility of differentiating children who perform below expectations because of poor dichotic processing skills from those who perform poorly because of impaired attention, memory, or other cognitive abilities. The high correlation between dichotic and diotic performance suggests that factors other than dichotic performance play a substantial role in a child's ability to perform a dichotic listening task. This hypothesis is investigated further in the cognitive correlation study that follows in the companion paper (DDdT Study Part 2; Cameron et al, 2016). [ABSTRACT FROM AUTHOR]

Background: The Dichotic Digits difference Test (DDdT) was developed to investigate the relationship between dichotic processing and cognitive abilities and, through the use of differential test scores, to provide professionals with a clinical tool that could aid in differentiation of clients with genuine dichotic deficits from those where cognitive disorders affect test performance. The DDdT consists of four subtests: dichotic free recall (FR), dichotic directed left ear, dichotic directed right ear, and diotic. Scores are calculated for six conditions: FR left ear (LE), right ear (RE), and total, as well as the directed left ear, directed right ear, and diotic, and four difference measures: dichotic advantage, RE advantage FR, RE advantage directed, and attention advantage. Purpose: To investigate the role of cognitive abilities on DDdT test performance. Research Design: Correlational analysis between the various DDdT conditions and difference measures, as well as between dichotic, diotic, and cognitive factors (memory, intelligence, and attention). Study Sample: Fifty typically developing children (aged 7 yr 0 mo to 12yr 1 mo, mean = 9yr2mo) and ten children recruited from the Australian Flearing CAPD Service who were diagnosed with a memory or dichotic deficit (aged 7 yr 0 mo to 15 yr 0 mo, mean = 9 yr 5 mo) took part in the study. Data Collection and Analysis: The Pearson product moment correlations were used to determine the strength of relationships between DDdT conditions as well as relationships between scores on these conditions and performance on the various cognitive assessment tools, which included the number memory forward and reversed subtests of the Test of Auditory Processing Skills-Third Edition, IVA + Plus Continuous Performance Test, and the Test of Non-Verbal Intelligence-4 (TONI-4). A parent questionnaire (Fisher's Auditory Checklist) and a participant questionnaire (Listening Inventory for Education) were also administered. Results: Diotic performance was significantly correlated with performance on all the DDdT dichotic FR conditions (r = 0.6-0.8; p < 0.00001). Further, significant correlations were found between the FR LE, total, and diotic conditions, and the cognitive measures of attention and memory, with r ranging from 0.4 to 0.5 (p < 0.01-0.001). Right-ear performance was not significantly correlated to any cognitive measure, except for FR RE and number memory forward (r = 0.35; p = 0.006). The DDdT dichotic advantage measure was investigated in a subset of clinical children and found to aid in differentiating true dichotic from spurious results. Conclusions: As found in the DDdT normative data study that precedes in the companion paper (DDdT Study Part 1; Cameron et al, 2016), the high correlation between dichotic and diotic performances by the clinical and typically developing participants suggests that factors other than dichotic performance play a substantial role in a child's ability to perform a dichotic listening task. Indeed, 61% of the variance in FR total scores for the children in this study was accounted for by factors that do not involve the perception of dichotic stimuli. This view is supported by the correlations between measures of attention and memory and dichotic scores. This result has wide-spread implications in respect to interpretation of central auditory processing disorder test results and further investigation of the use of the DDdT in a clinical population is warranted. [ABSTRACT FROM AUTHOR]

Anti-elementarity is a strong way of ensuring that a class of structures, in a given first-order language, is not closed under elementary equivalence with respect to any infinitary language of the form ℒ ∞ λ . We prove that many naturally defined classes are anti-elementary, including the following: the class of all lattices of finitely generated convex ℓ -subgroups of members of any class of ℓ -groups containing all Archimedean ℓ -groups; the class of all semilattices of finitely generated ℓ -ideals of members of any nontrivial quasivariety of ℓ -groups; the class of all Stone duals of spectra of MV-algebras — this yields a negative solution to the MV-spectrum Problem; the class of all semilattices of finitely generated two-sided ideals of rings; the class of all semilattices of finitely generated submodules of modules; the class of all monoids encoding the nonstable K0-theory of von Neumann regular rings, respectively, C*-algebras of real rank zero; (assuming arbitrarily large Erdős cardinals) the class of all coordinatizable sectionally complemented modular lattices with a large 4 -frame. The main underlying principle is that under quite general conditions, for a functor Φ : 𝒜 → ℬ , if there exists a noncommutative diagram D → of 𝒜 , indexed by a common sort of poset called an almost join-semilattice, such that Φ D → I is a commutative diagram for every set I , Φ D → ≇ Φ X → for any commutative diagram X → in 𝒜 , then the range of Φ is anti-elementary. [ABSTRACT FROM AUTHOR]

Phosphorus‐containing compounds have a long history of utility in a broad range of fields, including agricultural, pharmaceutical, and metal‐mediated reactions. In recent decades, numerous methods have been developed to streamline the synthesis of organophosphorus reagents based on these numerous applications. This review focuses upon the recent development of phosphorus(III)‐ and phosphorus(V)‐directed C−H borylation reactions. This transformation has evolved significantly in the past two years, resulting in several new methods that provide access to organic substrates containing both phosphorus and boron. Further functionalization of the carbon−boron bond to provide functionalized organophosphorus products is discussed. [ABSTRACT FROM AUTHOR]

• Directed C H functionalization is emergent as a powerful tool in organic synthesis. • Amides and thioamides are versatile directing groups for C(sp3) H activation. • Cyclometalation and amidyl radical based C(sp3) H functionalizations are reviewed. • Success stories in amide directed remote C(sp3) H functionalizations are highlighted. C H activation is gaining substantial attention from synthetic and process chemists in recent years. Regio- and stereo-selective C H functionalization particularly facilitated by carboxylic acids and derivatives as directing groups has been progressing to an extent that this transformation could be conceived as one of the steps to assemble molecules in modern retrosynthetic analysis. This digest paper covers the most recent developments in C(sp3) H functionalization using carboxylic acid derivatives such as amides or thioamides as a directing group and highlights new reaction discoveries and applications. The content of this review is organized based on the types of directing groups and the mechanism by which the C(sp3) H bond is believed to be activated. [ABSTRACT FROM AUTHOR]

This brief addresses the cooperative formation of self-propelled vehicles via the phase-based steering control. When the steering control law is designed for a directed Kuramoto-oscillator model with a pacemaker, all agents almost globally converge to either the synchronized formation or a two-cluster formation, if the following two conditions hold: 1) the augmented digraph contains a directed spanning tree and satisfies the decoupling assumption and 2) one of the strengths that influenced by the pacemaker is larger than the critical value. Cooperative formation in the case of pacemaker-free steering control may also hold under its conditions. Numerical examples illustrate the effectiveness of the derived analytical results. [ABSTRACT FROM AUTHOR]

A regio‐ and stereoselective nickel‐catalyzed hydroarylation of alkynes using propargylic carbamates as directing groups has been developed. The reaction proceeds under mild reaction conditions using arylboronic acids in the absence of base. A range of heterocycles and functional groups are tolerated under the reaction conditions, providing high yields of trisubstituted alkenes with control of olefin geometry. Stereoselective synthesis of trisubstituted alkenes using a nickel catalyst under mild reaction conditions is reported. A propargylic carbamate serves as a directing group. Products are allylic carbamates that can undergo further transformation, for example, by copper‐mediated allylic substitution [ABSTRACT FROM AUTHOR]

We propose a class of random scale-free spatial networks with nested community structures called SHEM and analyze Reed-Frost epidemics with community related independent transmissions. We showthat in a specific example of theSHEMthe epidemic threshold may be trivial or not as a function of the relation among community sizes, distribution of the number of communities, and transmission rates. [ABSTRACT FROM AUTHOR]

Abstract: For a detailed review of this subject I refer to a recent paper [S.A. Voloshin, A.M. Poskanzer and R. Snellings, arXiv:0809.2949 [nucl-ex]]; in this talk I only very briefly comment on a few most important questions: (a) Very recent significant progress in viscous hydrodynamics calculations. (b) Initial eccentricity/flow fluctuations, the effect of which has been clarified recently. (c) Initial conditions, in particular the role of the gradients in the initial velocity field. (d) Puzzling system size dependence of directed flow. (e) Azimuthal correlations that are sensitive to the strong parity violation. (f) Future measurements at RHIC and LHC, including pp-collisions. [Copyright &y& Elsevier]

Consider n synchronous network of processors, modeled by directed or undirected graph G = (V, E), in which in each round every processor is allowed to choose one of its neighbors and to send a message to this neighbor. Given n processor s ∈ V and n subset T ⊆ V of processors, the telephone multicast problem requires computing the shortest schedule (in terms of the number of rounds) that delivers a message from s to all the processors of T. The particular case T = V is called the telephone broadcast problem. These problems have multiple applications in distributed computing. Several approximation algorithms with polylogarithmic ratio, including one with logarithmic ratio, for the undirected variants of these problems are known. However, all these algorithms involve solving large linear programs. Devising a polylogarithmic approximation algorithm for the directed variants of these problems is an open problem, posed by Ravi in [Proceedings of the 35th Annual IEEE Symposium on Foundations of Computer Science (FOCS `94), 1994, pp. 202-213[ We devise a combinatorial logarithmic approximation algorithm for these problems that applies also for the directed broadcast problem. Our algorithm has significantly smaller running time and seems to reveal more information about the combinatorial structure of the solution than the previous algorithms that are based on linear programming. We also improve the lower bounds on the approximation threshold of these problems. Both problems are known to be 3/2-inapproximable. For the undirected (resp., directed) broadcast problem we show that it is NP-hard (resp., impossible unless NP ⊆ DT1 ME(nO (log n))) to approximate it within a ratio of 3 - ε for any ε > 0 (resp., Ω(√logn)). [ABSTRACT FROM AUTHOR]

A simple, high-yield procedure has been developed for the ortho-lithiation and subsequent ortho-substitution of phenols by a manifold of electrophiles. N,C-Dilithiation of O-aryl N-monoalkylcarbamates proved to be impossible due to a cleavage reaction of the monolithiated intermediates. However, in situ N-silylation of O-aryl N-isopropylcarbamates proceeds smoothly with trialkylsilyl triflates – N,N,N',N'-tetramethylethylenediamine (TMEDA). Separation of the formed O-aryl N-isopropyl-N-trialkylsilylcarbamates from the byproduct TMEDA·HOTf, which is insoluble in diethyl ether or toluene, is not required. ortho-Lithiation with n-butyllithium–TMEDA at –78°C leads to the corresponding aryllithium, which does not undergo anionic ortho-Fries rearrangement under the reaction conditions, but is efficiently substituted by electrophilic reagents. During the aqueous work-up, the N-silyl group is removed and the corresponding ortho-substituted O-aryl N-isopropylcarbamate is isolated. Among the introduced electrophiles are: Me[sub 3] Si, Bu[sub 3] Sn, PhS, I, Br, Cl, alkyl, α-hydroxyalkyl. Liberation of the free phenols is performed under mild alkaline conditions.Key words: directed ortho-metalation, ortho-lithiated O-aryl carbamates, ortho-substituted phenols, in situ protection of N-monoalkylcarbamates.On a mis au point une méthode simple qui permet d'effectuer avec des rendements élevés l'ortho-lithiation et l'ortho-substitution subséquente de phénols par un grand nombre d'électrophiles. Les N,C-dilithiations d'O-aryl N-monoalkylcarbamates s'avèrent impossibles en raison de la réaction de clivage des intermédiaires monolithiés. Toutefois, la N-silylation in situ des O-aryl N-isopropylcarbamates peut être réalisée facilement avec les couples triflates de trialkylsilyle – N,N,N',N'-tétraméthyléthylènediamine (TMEDA). Il n'est pas nécessaire de séparer les O-aryl N-isopropyl-N-trialkylsilylcarbamates des sous-produits, TMEDA·HOTf qui sont insolubles dans l'éther éthylique ou le toluène. L'ortho-lithiation avec du n-butyllithium–TMEDA, à –78°C, conduit à la formation de l'aryllithien correspondant, qui ne donne pas lieu à un réarrangement d'ortho-Fries anionique dans les conditions de la réaction mais qui donne lieu à des réactions de substitution sous l'influence de réactifs électrophiles. Lors de la procédure d'extraction, le groupe N-silyle est éliminé et on peut isoler le O-aryl N-isopropylcarbamate ortho-substitué. Les électrophiles qui ont été introduits sont: Me[sub 3] Si, Bu[sub 3] Sn, PhS, I, Br, Cl, alkyle, α-hydroxyalkyle. La libération des phénols se fait dans des conditions alcalines douces.Mots clés : ortho-métallation orientée, O-aryl carbamates ortho-lithiés, phénols ortho-substitués, protection in situ de N-monoalkylcarbamates.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]