Concordia University

About: Concordia University is a education organization based out in Montreal, Quebec, Canada. It is known for research contribution in the topics: Context (language use) & Control theory. The organization has 13565 authors who have published 31084 publications receiving 783525 citations. The organization is also known as: Sir George Williams University & Loyola College, Montreal.

Mixcoin: Anonymity for Bitcoin with Accountable Mixes

Abstract: We propose Mixcoin, a protocol to facilitate anonymous payments in Bitcoin and similar cryptocurrencies. We build on the emergent phenomenon of currency mixes, adding an accountability mechanism to expose theft. We demonstrate that incentives of mixes and clients can be aligned to ensure that rational mixes will not steal. Our scheme is efficient and fully compatible with Bitcoin. Against a passive attacker, our scheme provides an anonymity set of all other users mixing coins contemporaneously. This is an interesting new property with no clear analog in better-studied communication mixes. Against active attackers our scheme offers similar anonymity to traditional communication mixes.

The Information Technology Outsourcing Risk: A Transaction Cost and Agency Theory-Based Perspective

Abstract: Many firms have adopted outsourcing in recent years as a means of governing their information technology (IT) operations. While outsourcing is associated with significant benefits, it can also be a risky endeavour. This paper proposes a scenario-based conceptualization of the IT outsourcing risk, wherein risk is defined as a quadruplet comprising a scenario, the likelihood of that scenario, its consequences and the risk mitigation mechanisms that can attenuate or help avoid the occurrence of a scenario. This definition draws on and extends a risk assessment framework that is widely used in engineering. The proposed conceptualization of risk is then applied to the specific context of IT outsourcing using previous research on IT outsourcing as well as transaction cost and agency theory as a point of departure.

Gift Giving in Hong Kong and the Continuum of Social Ties

Abstract: This article explores gift‐giving practices using data collected through interviews in Hong Kong. I argue that Chinese culture promotes the familial over the private self and that the attainment of family‐oriented goals represents an important measure of self‐realization and self‐fulfillment. Although each individual also has a private or inner self (chi), it is also subject to the collective will. This idea is in keeping with Confucian ideals that encourage the individual to focus on developing internal moral constraints and conquering selfishness in the pursuit of social propriety. Furthermore, the boundaries of the familial self are permeable and may include others, such as important romantic partners and, occasionally, close friends who become “like family.” In family and like‐family contexts, reciprocity is discouraged, and there is no need to build relationships through gift giving. Our research also suggests, however, that there are various gradations of intimacy in gift relationships against the b...

Action of drugs of abuse on brain reward systems.

Abstract: The finding that animals will work for electrical stimulation of some but not all parts of the brain has prompted the view that there are specialized brain circuits which subserve reward function. Two synaptic links in this circuitry have been partially identified. Studies of the effective stimulation parameters indicate that the directly activated fibers are usually high-frequency-sensitive, fast-conducting, myelinated fibers. Pharmacological studies suggest that all reward sites tested are afferent to a critical dopaminergic synapse; the myelinated, reward-relevant fiber of the medial forebrain bundle may synapse directly on the dopamine link. Dopamine blockers block self-stimulation regardless of electrode placement, and dopamine agonists are rewarding in their own right; thus the critical dopaminergic synapse plays both a necessary and (with its normal efferents) a sufficient role in reward function. Several drugs of abuse can facilitate self-stimulation, and it is hypothesized that they do so by a direct action on the same neural substrate. Amphetamine and cocaine seem to act directly in the critical dopamine synapse. Opiates might act at the dopamine synapse or cell bodies, or might act on dopamine afferents. Ethanol, barbiturates and benzodiazepines have not been extensively explored, but if their reported facilitations of self-stimulation are reliable they might be suggested to cause them by a naloxone-reversible inhibition of noradrenergic function, which disinhibits rather than directly excites the dopamine reward link. These suggestions as to the possible sites of interaction of drugs of abuse with brain stimulation reward circuitry are speculative, and are advanced as potentially heuristic working hypotheses.