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1.
J Nat Prod ; 76(9): 1815-8, 2013 Sep 27.
Article in English | MEDLINE | ID: mdl-23987585

ABSTRACT

Farnesides A and B (1, 2), linear sesquiterpenoids connected by ether links to a ribose dihydrouracil nucleoside, were isolated from a marine-derived Streptomyces sp., strain CNT-372, grown in saline liquid culture. The structures of the new compounds were assigned by comprehensive spectroscopic analysis primarily involving 1D and 2D NMR analysis and by comparison of spectroscopic data to the recently reported ribose nucleoside JBIR-68 (3). The farnesides are only the second example of this exceedingly rare class of microbial terpenoid nucleoside metabolites. Farneside A (1) was found to have modest antimalarial activity against the parasite Plasmodium falciparum.


Subject(s)
Antimalarials/isolation & purification , Nucleosides/isolation & purification , Plasmodium falciparum/drug effects , Sesquiterpenes/isolation & purification , Streptomyces/chemistry , Antimalarials/chemistry , Antimalarials/pharmacology , Drug Screening Assays, Antitumor , Fiji , HCT116 Cells , Humans , Marine Biology , Molecular Structure , Monosaccharides/chemistry , Nuclear Magnetic Resonance, Biomolecular , Nucleosides/chemistry , Nucleosides/pharmacology , Parasitic Sensitivity Tests , Pyrimidinones/chemistry , Sesquiterpenes/chemistry , Sesquiterpenes/pharmacology
2.
Sci Rep ; 3: 1544, 2013.
Article in English | MEDLINE | ID: mdl-23536118

ABSTRACT

Violent extremist groups are currently making intensive use of Internet fora for recruitment to terrorism. These fora are under constant scrutiny by security agencies, private vigilante groups, and hackers, who sometimes shut them down with cybernetic attacks. However, there is a lack of experimental and formal understanding of the recruitment dynamics of online extremist fora and the effect of strategies to control them. Here, we utilize data on ten extremist fora that we collected for four years to develop a data-driven mathematical model that is the first attempt to measure whether (and how) these external attacks induce extremist fora to self-regulate. The results suggest that an increase in the number of groups targeted for attack causes an exponential increase in the cost of enforcement and an exponential decrease in its effectiveness. Thus, a policy to occasionally attack large groups can be very efficient for limiting violent output from these fora.


Subject(s)
Aggression , Internet , Terrorism/prevention & control , Aggression/psychology , Humans , Models, Theoretical , Personnel Selection
3.
Soc Sci Q ; 92(1): 100-18, 2011.
Article in English | MEDLINE | ID: mdl-21534269

ABSTRACT

Objective. This article offers a test of the normative explanation of collective behavior by examining the fire at the Station nightclub in Rhode Island that killed 100 and injured nearly 200 persons.Methods. Information on all persons at the club comes from content analysis of documents from the Rhode Island Police Department, the Rhode Island Office of the Attorney General, and The Providence Journal. We use negative binomial regression to test hypotheses about the effects of group-level predictors of the counts of dead and injured in 179 groups at the nightclub.Results. Results indicate that group-level factors such as distance of group members at the start of the fire, the number of intimate relations among them, the extent to which they had visited the nightclub prior to the incident, and the average length of the evacuation route they used predict counts of injured and dead. The research also looks at what behavioral differences exist between survivors and victims, ascertains the existence of role extension among employees of the nightclub, and provides support for the affirmation that dangerous contexts negate the protective influence of intimate relations in groups.Conclusion. We argue for the abandonment of current emphasis on irrationality and herd-like imitative behavior in studies of evacuation from structural fires in buildings and for the inclusion of group-level processes in social psychological explanations of these incidents.


Subject(s)
Crime Victims , Fires , Psychology, Social , Social Behavior , Survivors , Behavioral Research/education , Behavioral Research/history , Crime Victims/history , Crime Victims/psychology , Fires/economics , Fires/history , Fires/legislation & jurisprudence , History, 21st Century , Interpersonal Relations/history , Psychology, Social/education , Psychology, Social/history , Rhode Island/ethnology , Safety/history , Social Behavior/history , Survivors/history , Survivors/psychology
4.
Disasters ; 31(4): 495-507, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18028166

ABSTRACT

In the aftermath of disasters it is not uncommon for a large number of individuals, ranging from professional technical responders to untrained, albeit well meaning, volunteers, to converge on site of a disaster in order to offer to help victims or other responders. Because volunteers can be both a help and a hindrance in disaster response, they pose a paradox to professional responders at the scene. Through focus group interviews and in-depth structured interviews, this paper presents an extended example of how Urban Search and Rescue (US&R) task forces, a type of professional technical-responder organisation, interact with and utilise volunteers. Findings show that US&R task forces evaluate the volunteers in terms of their presumed legitimacy, utility, and potential liability or danger posed during the disaster response. Other responses to volunteers such as a feeling of powerlessness or the use of volunteers in non-technical ways are also explored. This paper demonstrates some key aspects of the relationship between volunteers and formal response organisations in disasters.


Subject(s)
Disaster Planning/organization & administration , Disasters , Emergency Medical Services/organization & administration , Human Experimentation , Relief Work , Urban Population , Focus Groups , Humans , Interviews as Topic , United States
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