Managing the gilt pool

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Nicotinamide's Ups and Downs:Consequences for Fertility, Development, Longevity and Diseases of Poverty and Affluence

Aims and Scope: To further explore the role of dietary nicotinamide in both brain development and diseases, particularly those of ageing. Articles cover neurodegenerative disease and cancer. Also discussed are the effects of nicotinamide, contained in meat and supplements and derived from symbionts, on the major transitions of disease and fertility from ancient times up to the present day. A key role for the tryptophan – NAD ‘de novo’ and immune tolerance pathway are discussed at length in the context of fertility and longevity and the transitions from immune paresis to Treg-mediated immune tolerance and then finally to intolerance and their associated diseases. Abstract: Nicotinamide in human evolution increased cognitive power in a positive feedback loop originally involving hunting. As the precursor to metabolic master molecule NAD it is, as vitamin B3, vital for health. Paradoxically, a lower dose on a diverse plant then cereal-based diet fuelled population booms from the Mesolithic onwards, by upping immune tolerance of the foetus. Increased tolerance of risky symbionts, whether in the gut or TB, that excrete nicotinamide co-evolved as buffers for when diet was inadequate. High biological fertility, despite disease trade-offs, avoided the extinction of Homo sapiens and heralded the dawn of a conscious, creative, and pro-fertility culture. Nicotinamide equity now would stabilise populations and prevent NAD-based diseases of poverty and affluence

The role of control in attributing intentional agency to inanimate objects

Previous research into the perception of agency has found that objects in two-dimensional displays that move along non-inertial-looking paths are frequently attributed intentional agency, including beliefs and desires. The present experiment re-addressed this finding using a tangible, interactive, electromagnetic puzzle. The experimental manipulation was whether or not participants controlled the electromagnet that moved the marbles along unexpected trajectories. Thirty-one college undergraduates participated. Participants who lacked control over the movement of the marbles were significantly more likely to attribute agency to the marbles. Participants in control of the display rarely attributed intentional agency to the marbles. Implications are discussed for the identification of agents in the real world

A Formalization of Off-Line Guessing for Security Protocol Analysis

Guessing, or dictionary, attacks arise when an intruder exploits the fact that certain data like passwords may have low entropy, i.e. stem from a small set of values. In the case of off-line guessing, in particular, the intruder may employ guessed values to analyze the messages he has observed. Previous attempts at formalizing off-line guessing consist of extending a Dolev-Yao-style intruder model with inference rules to capture the additional capabilities of the intruder concerning guessable messages. While it is easy to convince oneself that the proposed rules are correct, in the sense that an intruder can actually perform such \u201cguessing steps\u201d, it is difficult to see whether such a system of inference rules is complete in the sense that it captures all the kinds of attacks that we would intuitively call \u201cguessing attacks\u201d. Moreover, the proposed systems are specialized to particular sets of cryptographic primitives and intruder capabilities. As a consequence, these systems are helpful to discover some off-line guessing attacks but are not fully appropriate for formalizing what off-line guessing precisely means and verifying that a given protocol is not vulnerable to such guessing attacks. In this paper, we give a formalization of off-line guessing by defining a deduction system that is uniform and general in that it is independent of the overall protocol model and of the details of the considered intruder model, i.e. cryptographic primitives, algebraic properties, and intruder capabilities

Formalizing and Analyzing Sender Invariance

In many network applications and services, agents that share no secure channel in advance may still wish to communicate securely with each other. In such settings, one often settles for achieving security goals weaker than authentication, such as sender invariance. Informally, sender invariance means that all messages that seem to come from the same source actually do, where the source can perhaps only be identified by a pseudonym. This implies, in particular, that the relevant parts of messages cannot be modified by an intruder. In this paper, we provide the first formal definition of sender invariance as well as a stronger security goal that we call strong sender invariance. We show that both kinds of sender invariance are closely related to, and entailed by, weak authentication, the primary difference being that sender invariance is designed for the context where agents can only be identified pseudonymously. In addition to clarifying how sender invariance and authentication are related, this result shows how a broad class of automated tools can be used for the analysis of sender invariance protocols. As a case study, we describe the analysis of two sender invariance protocols using the OFMC back-end of the AVISPA Tool

A High Level Protocol Specification Language for Industrial Security-Sensitive Protocols

This paper presents HLPSL, a high level protocol specification language for the modelling of security-sensitive protocols. This language has a formal semantics based on Lamport’s Temporal Logic of Actions. HLPSL is modular and allows for the specification of control flow patterns, data-structures, alternative intruder models, and complex security properties. It is sufficiently highlevel to be accessible to protocol engineers (themselves not necessarily formal methods experts), yet easily translatable into a lower-level term-rewriting based language well-suited to model-checking tools. The accommodation of these contrasting features makes HLPSL able to easily specify modern, industrial-scale protocols on which existing specification languages only partially succeed