Learned temporal statistics guide information seeking and shape memory.

Author(s):  
Emily A. Lang ◽  
Camilla van Geen ◽  
Ellen Tedeschi ◽  
Caroline B. Marvin ◽  
Daphna Shohamy
2019 ◽  
Vol 42 ◽  
Author(s):  
Jessica L. Alquist ◽  
Roy F. Baumeister

AbstractWhen an environment is uncertain, humans and other animals benefit from preparing for and attempting to predict potential outcomes. People respond to uncertainty both by conserving mental energy on tasks unrelated to the source of the uncertainty and by increasing their attentiveness to information related to the uncertainty. This mental hoarding and foraging allow people to prepare in uncertain situations.


Author(s):  
F. I. Grace

An interest in NiTi alloys with near stoichiometric composition (55 NiTi) has intensified since they were found to exhibit a unique mechanical shape memory effect at the Naval Ordnance Laboratory some twelve years ago (thus refered to as NITINOL alloys). Since then, the microstructural mechanisms associated with the shape memory effect have been investigated and several interesting engineering applications have appeared.The shape memory effect implies that the alloy deformed from an initial shape will spontaneously return to that initial state upon heating. This behavior is reported to be related to a diffusionless shear transformation which takes place between similar but slightly different CsCl type structures.


Author(s):  
J.M. Guilemany ◽  
F. Peregrin

The shape memory effect (SME) shown by Cu-Al-Mn alloys stems from the thermoelastic martensitic transformation occuring between a β (L2,) metastable phase and a martensitic phase. The TEM study of both phases in single and polycrystalline Cu-Al-Mn alloys give us greater knowledge of the structure, order and defects.The alloys were obtained by vacuum melting of Cu, Al and Mn and single crystals were obtained from polycrystalline alloys using a modified Bridgman method. Four different alloys were used with (e/a) ranging from 1.41 to 1.46 . Two different heat treatments were used and the alloys also underwent thermal cycling throughout their characteristic temperature range -Ms, Mf, As, Af-. The specimens were cut using a low speed diamond saw and discs were mechanically thinned to 100 μm and then ion milled to perforation at 4 kV. Some thin foils were also prepared by twin-jet electropolishing, using a (1:10:50:50) urea: isopropyl alcohol: orthophosphoric acid: ethanol solution at 20°C. The foils were examinated on a TEM operated at 200 kV.


Crisis ◽  
2015 ◽  
Vol 36 (3) ◽  
pp. 211-219 ◽  
Author(s):  
Vinod Singaravelu ◽  
Anne Stewart ◽  
Joanna Adams ◽  
Sue Simkin ◽  
Keith Hawton

Abstract. Background: The Internet is used by young people at risk of self-harm to communicate, find information, and obtain support. Aims: We aimed to identify and analyze websites potentially accessed by these young people. Method: Six search terms, relating to self-harm/suicide and depression, were input into four search engines. Websites were analyzed for access, content/purpose, and tone. Results: In all, 314 websites were included in the analysis. Most could be accessed without restriction. Sites accessed by self-harm/suicide search terms were mostly positive or preventive in tone, whereas sites accessed by the term ways to kill yourself tended to have a negative tone. Information about self-harm methods was common with specific advice on how to self-harm in 15.8% of sites, encouragement of self-harm in 7.0%, and evocative images of self-harm/suicide in 20.7%. Advice on how to get help was given in 56.1% of sites. Conclusion: Websites relating to suicide or self-harm are easily accessed. Many sites are potentially helpful. However, a significant proportion of sites are potentially harmful through normalizing or encouraging self-harm. Enquiry regarding Internet use should be routinely included while assessing young people at risk.


Crisis ◽  
2017 ◽  
Vol 38 (3) ◽  
pp. 207-209 ◽  
Author(s):  
Florian Arendt ◽  
Sebastian Scherr

Abstract. Background: Research has already acknowledged the importance of the Internet in suicide prevention as search engines such as Google are increasingly used in seeking both helpful and harmful suicide-related information. Aims: We aimed to assess the impact of a highly publicized suicide by a Hollywood actor on suicide-related online information seeking. Method: We tested the impact of the highly publicized suicide of Robin Williams on volumes of suicide-related search queries. Results: Both harmful and helpful search terms increased immediately after the actor's suicide, with a substantial jump of harmful queries. Limitations: The study has limitations (e.g., possible validity threats of the query share measure, use of ambiguous search terms). Conclusion: Online suicide prevention efforts should try to increase online users' awareness of and motivation to seek help, for which Google's own helpline box could play an even more crucial role in the future.


Sign in / Sign up

Export Citation Format

Share Document