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1.
J Nat Prod ; 76(9): 1815-8, 2013 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-23987585

RESUMEN

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.


Asunto(s)
Antimaláricos/aislamiento & purificación , Nucleósidos/aislamiento & purificación , Plasmodium falciparum/efectos de los fármacos , Sesquiterpenos/aislamiento & purificación , Streptomyces/química , Antimaláricos/química , Antimaláricos/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Fiji , Células HCT116 , Humanos , Biología Marina , Estructura Molecular , Monosacáridos/química , Resonancia Magnética Nuclear Biomolecular , Nucleósidos/química , Nucleósidos/farmacología , Pruebas de Sensibilidad Parasitaria , Pirimidinonas/química , Sesquiterpenos/química , Sesquiterpenos/farmacología
2.
Sci Rep ; 3: 1544, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23536118

RESUMEN

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.


Asunto(s)
Agresión , Internet , Terrorismo/prevención & control , Agresión/psicología , Humanos , Modelos Teóricos , Selección de Personal
3.
Soc Sci Q ; 92(1): 100-18, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21534269

RESUMEN

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.


Asunto(s)
Víctimas de Crimen , Incendios , Psicología Social , Conducta Social , Sobrevivientes , Investigación Conductal/educación , Investigación Conductal/historia , Víctimas de Crimen/historia , Víctimas de Crimen/psicología , Incendios/economía , Incendios/historia , Incendios/legislación & jurisprudencia , Historia del Siglo XXI , Relaciones Interpersonales/historia , Psicología Social/educación , Psicología Social/historia , Rhode Island/etnología , Seguridad/historia , Conducta Social/historia , Sobrevivientes/historia , Sobrevivientes/psicología
4.
Disasters ; 31(4): 495-507, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18028166

RESUMEN

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.


Asunto(s)
Planificación en Desastres/organización & administración , Desastres , Servicios Médicos de Urgencia/organización & administración , Experimentación Humana , Sistemas de Socorro , Población Urbana , Grupos Focales , Humanos , Entrevistas como Asunto , Estados Unidos
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