798 research outputs found
Automated Abstractions for Patrolling Security Games
No full textRecently, there has been a significant interest in studying security games to provide tools for addressing resource allocation problems in security applications. Patrolling security games (PSGs) constitute a special class of security games wherein the resources are mobile. One of the most relevant open problems in security games is the design of scalable algorithms to tackle realistic scenarios. While the literature mainly focuses on heuristics and decomposition techniques (e.g., double oracle), in this paper we provide, to the best of our knowledge, the first study on the use of abstractions in security games (specifically for PSGs) to design scalable algorithms. We define some classes of abstractions and we provide parametric algorithms to automatically generate abstractions. We show that abstractions allow one to relax the constraint of patrolling strategies' Markovianity (customary in PSGs) and to solve large game instances. We additionally pose the problem to search for the optimal abstraction and we develop an anytime algorithm to find it
Antiprotozoal activity of novel diaryliminophenazines
No full textRecently, we synthesized a set of novel iminofenazines bearing a bicyclic basic head linked through an alkyl chain to the imino nitrogen in position 3 on the phenazine nucleus (Fig.1).
Most of these compounds inhibited the growth of different species of Leishmania promastigotes as well as of chloroquine sensitive (CQ-S) and chloroquine resistant (CQ-R) strains of P. falciparum with IC50 in the submicromolar range. Unfortunately, these compounds exhibited also a significant toxicity against the human endothelial cell line HMEC-1 with IC50 in the low micromolar range and with a consequent low selectivity index.
Figure1.Structures of the previously synthesized compounds.
To continue the studies on the antiprotozoal potentialities of this class of compounds and with the aim to improve their activity and selectivity on protozoa, we have now synthesized novel compounds characterized by the replacement of the aniline moiety in pos. 2 of the phenazine nucleus with an aminopyridine, and/or by a quaternarization of the basic nitrogen in the side chain with a methyl group (Fig.2).
Figure 2. Structures of the new compounds synthesized.
The in vitro activity of the new compounds on Leishmania promastigotes and on CQ-S and CQ-R strains of P. falciparum, as well as on the HMEC-1 cell line will be presented and discussed.
References
[1] A. Barteselli, M. Gavazzi, N. Basilico, S. Parapini, D. Taramelli, A. Sparatore. Clofazimine analogs with antileishmanial and antimalarial activities. XXII National Meeting on Medicinal Chemistry, Roma 2013
Linaria officinarum, Basilico, Sisaro
No full text1. Nome scientifico: Linaria vulgaris Miller
(Scrophulariaceae)
Nome attuale: Linaiola
2. Nome scientifico: Ocimum basilicum L.
(Lamiaceae, Labiatae)
Nome attuale: Basilico
3. Nome scientifico: Sium sisarum L.
(Apiaceae, Umbelliferae)
Nome attuale: Sisaro, Sedanin
Antiplasmodial triterpenoids from the fruits of neem, Azadirachta indica.
No full textJ Nat Prod. 2010 Aug 27;73(8):1448-52.
Antiplasmodial triterpenoids from the fruits of neem, Azadirachta indica.
Chianese G, Yerbanga SR, Lucantoni L, Habluetzel A, Basilico N, Taramelli D, Fattorusso E, Taglialatela-Scafati O.
Abstract
Eight known and two new triterpenoid derivatives, neemfruitins A (9) and B (10), have been isolated from the fruits of neem, Azadirachta indica, a traditional antimalarial plant used by Asian and African populations. In vitro antiplasmodial tests evidenced a significant activity of the known gedunin and azadirone and the new neemfruitin A and provided useful information about the structure-antimalarial activity relationships in the limonoid class
Strategic guard placement for optimal response to alarms in security games
No full textWe introduce a Security Game with a single static guard that is supported by a number of spatially imperfect alarms. We model this setting with two non-cooperative games modeling two different strategic interactions between a Defender and an Attacker. In the first one the Defender has to respond to an activated alarm given its current position (Alarm-Response Game). In the second one, the Defender has to determine the best static placement from which undertakes any alarm response (Guard-Placement Game)
Capturing augmented sensing capabilities and intrusion delay in patrolling-intrusion games
No full textPatrolling-intrusion games are recently receiving more and more attention in the literature. They are twoplayer non zero-sum games where an intruder tries to attack one place of interest and one patroller (or more) tries to capture the intruder. The patroller cannot completely cover the environment following a cycle, otherwise the intruder will successfully strike at least a target. Thus, the patroller employs a randomized strategy. These games are usually studied as leader-follower games, where the patroller is the leader and the intruder is the follower. The models proposed in the state of the art so far present several limitations that prevent their employment in realistic settings. In this paper, we refine the models from the state-of-the-art capturing patroller's augmented sensing capabilities and a possible delay in the intrusion, we propose algorithms to solve efficiently our extensions, and we experimentally evaluate the computational time in some case studies
Integrating Partial Models of Network Normality via Cooperative Negotiation - An Approach to Development of Multiagent Intrusion Detection Systems
No full textUsing agents for developing intrusion detection systems can provide several advantages, including configurability, adaptability, scalability, and robustness. Almost all works in agent-based intrusion detection have considered agents as elements that perform specific tasks in the intrusion detection process. In this paper, we propose a novel way of using agents to solve one of the most pressing problems in intrusion detection: the definition of an accurate model of network normality. We consider agents as associated to partial models of network normality that harmonize their conflicts via cooperative negotiation. Experimental results show that the proposed approach is promising
A Game Theoretical Approach to Finding Optimal Strategies forPursuit Evasion in Grid Environments
No full textDeploying teams of heterogeneous UAVs in cooperative two-level surveillance missions
No full textWe consider the problem of providing surveillance to a grid area using multiple heterogeneous UAVs, named sentinels and searchers, with complementary sensing and actuation capabilities. We consider probabilistic attacks and we analyze the expected performance with respect to the team deployment. We then introduce the problem of finding minmax deployments that result in the most desirable worst case performance caused by an attack. We present an algorithm to compute deployments while trading off solution's quality and computational effort and we qualitatively and quantitatively analyze it
- …
